Genetic Testing to Understand and Address Renal Disease Disparities Across the United States - Pharmacogenetic Substudy
Phase: NA
Conditions: Chronic Kidney Disease, Hypertension
Sponsor: Duke University

1 
Genetic testing to Understand and Address Renal Disease Disparities 
across the United States (GUARDD-US) 
Principal Investigator: Carol R. Horowitz, MD, MPH 
Co-Investigator: Girish Nadkarni, MD 
Statistical Investigator: Hrishikesh Chakraborty, DrPH 
Clinicaltrial.gov #: NCT04191824, NCT06748040 
Funded by: National Human Genome Research Institute 
Version Number: v6.0 
19 March 2024 

 
2 
 
PROTOCOL VERSION AND AMENDMENT TRACKING 
Version Number/ 
Affected Section(s) 
Summary of Revisions Made 
Version Date 
1/ Protocol Version 
and 
Amendment 
Tracking; Investigator 
Statement; 
Abbreviations; 
Protocol 
Synopsis; 
Sections 4,5,6,7, 8, 9, 
10 and Appendix B   
• 
Protocol Version and Amendment 
Tracking – added Amendment 1 
change information 
• 
Investigator 
Statement 
– 
updated 
protocol version date 
• 
Abbreviations – removed reference to 
PROMIS and PROPr 
• 
Protocol 
synopsis 
– 
number 
of 
recruitment sites, inclusion criteria 
definition of CKD and exclusion criteria 
definition of terminal illness 
• 
Section 4 – Study Design – explain 
randomization plan 
• 
Section 5 – inclusion criteria to clarify 
CKD definition and exclusion definition 
of terminal illness 
• 
Section 6 – clarified information on 
EHR queries, provider consent, use of 
recruitment script as optional, changed 
will to may and should, clarified 
consenting process and timeline for 
completing the baseline visit, and 
clarified compensation  
• 
Section 
7 
– 
clarified 
education 
materials and APOL1 results, clarified 
the recommendation for drug class, 
clarified 
baseline 
assessment 
completion, 
specimen 
collection 
guidelines, added secure email as 
method of return of results 
• 
Section 8 – added information on 
reportable 
events 
and 
removed 
meeting location 
• 
Section 9 – updated cost effective 
analysis plan 
• 
Section 10 – added pulse to data 
collection points 
• 
Section 15 – Appendix B – clarified 
recommendation 
section 
for 
poor/normal/rapid metabolizers 
05February2020 
2/ Protocol Version 
and 
Amendment 
Tracking; Investigator 
Statement; Protocol 
• 
Protocol Version and Amendment 
Tracking – added Amendment 2 
change information 
22June2020 

 
3 
 
Synopsis; 
Sections 
6,7, and 9    
• 
Investigator 
Statement 
– 
updated 
protocol version date 
• 
Protocol Synopsis – changed analysis 
method from Mann-Whitney to t-test 
under main study analyses 
• 
Section 
6 
– 
Recruitment 
and 
Enrollment Procedures – added that 
“the consenting process can be remote, 
via phone or electronically if approved 
by the reviewing IRB”. 
• 
Section 7 – Study Procedures – added 
that baseline survey and follow-up 
surveys may be administered over the 
phone.  
• 
Table 5 – changed “blood draw” to 
“sample collection” 
• 
Section 9 – changed “Mann-Whitney” to 
‘t-test” in Analysis of Primary Endpoint 
and Other Planned Analyses sections 
3/ 
Title 
Page; 
Protocol Version and 
Amendment 
Tracking; Investigator 
Statement; Protocol 
Synopsis; Sections 3, 
5,7, 8, 9, 10 and 11 
• 
Title page updates 
• 
Protocol Version and Amendment 
Tracking – added Amendment 3 
change information 
• 
Investigator 
Statement 
– 
updated 
protocol version date 
• 
Protocol synopsis – added in-person as 
option for return of PGx results, added 
new exclusion criteria (LVAD), clarified 
population 
for 
primary 
endpoint 
analysis, 
updated 
duration 
of 
participation for EHR data retrieval  
• 
Section 3 – Primary Endpoint – clarified 
population 
for 
primary 
endpoint 
analysis 
• 
Section 5 – Exclusion Criteria – added 
new exclusion criteria (LVAD) 
• 
Section 7 – Intervention/Treatment – 
clarified distribution methods for written 
test results and added in-person for 
verbal communication of test results 
• 
Section 7 – Assessments – updated 
criteria for which blood pressure 
reading would activate the elevated 
blood pressure protocol, clarified the 
thresholds for the elevated BP protocol, 
updated 
screen 
failure 
definition, 
updated the guidance for which EMR 
27August2021 

 
4 
 
BP values would qualify for inclusion in 
the study database 
• 
Section 7 – Data from EMR – revised 
the % of participants that would be 
included in the first data extract, 
updated the timing for the final EHR 
extract, updated description for how the 
EHR download and transfer process 
instructions would be distributed 
• 
Section 7 – Clinical Decision Support – 
updated the description for how the 
CDS alert details will be distributed  
• 
Section 8 – Safety Assessment - 
revised the % of participants that would 
be included in the first data extract, 
updated the timing for the final EHR 
extract, updated description for how the 
EHR download and transfer process 
instructions would be distributed and 
added virtual as a meeting format 
• 
Section 9 – Statistical Analysis Plan – 
updated 
language 
describing 
the 
planned interim analyses.  
• 
Section 10 – Data management – 
Updated 
language 
regarding 
verification 
of 
laboratory 
results, 
revised the % of participants that would 
be included in the first data extract, 
updated the timing for the final EHR 
extract, updated description for how the 
EHR download and transfer process 
instructions would be distributed 
• 
Section 11 – Updated language under 
the confidentiality and privacy section 
regarding participant name disclosure.  
 
4 Title Page; Protocol 
Version 
and 
Amendment 
Tracking; Investigator 
Statement; Protocol 
Synopsis; Sections 3, 
5,7, 8, 9, 10 and 11 
• 
Title page and Investigator Statement 
• 
Protocol Version and Amendment 
Tracking – Changed “Approval date” to 
“Version Date”, added Amendment 3 
change information 
• 
Protocol Synopsis – updated number of 
participants 
under 
randomized 
population, added “~” to “6 months” for 
duration of participation and clarified 
inclusion criteria – changed “African 
American/Black” 
to 
“self-reported 
African ancestry” 
10Jun2022 

 
5 
 
• 
Section 4 – Study Design – added 
language regarding manual blood 
pressure collection. Updated numbers 
for randomized population, APOL1 
positive assumed percentage, numbers 
of population that would be in each arm 
for main study and PGx substudy. 
Changed power for PGx substudy from 
80% to 90%. 
• 
Section 5 – Study Population – 
updated/clarified inclusion criteria – 
changed “African American/Black” to 
“self-reported African ancestry” 
• 
Section 
6 
– 
Recruitment 
and 
Enrollment Procedures – added “Study 
staff may also ask current participants if 
they know anyone who would qualify for 
the study and provide them with study-
related contact information to share 
with others.”  
• 
Section 6.3 Screening Procedures – 
added 
“Screening 
may 
also 
be 
performed in a location agreed upon 
between a potential participant and the 
research team.”  
• 
Section 
6.4 
Participant 
Consent 
Process – added “also” after “The 
consenting process can”.  
• 
Section 
6.10 
Compensation 
to 
Participants – changed “or” to “and/or” 
in sentence “Participants may be 
reimbursed 
for 
travel 
or 
parking 
expenses per institutional specific 
policies.” 
• 
Section 7 – Study Procedures - Section 
7.2 Baseline Assessments – added 
“which may occur in a location agreed 
upon between potential participants 
and the research team,” after “At 
baseline”.   
• 
Section 7.2 Baseline Assessments – 
added “Manual blood pressures may be 
collected if necessary.”  
• 
Section 7.3 Follow-Up Assessments – 
added “in a location agreed upon 
between 
the 
participant 
and 
the 
research 
team” 
after 
“Participants 
enrolled in the study will meet with 
Research Coordinators”.   

 
6 
 
• 
Section 7.7 Data Collection from the 
Electronic Health Record – added “for 
Other Planned Analyses including” 
after “variables needed”. Deleted “in 
the” 
before 
“Cost 
Effectiveness 
Analysis”. 
• 
Section 7.10 Schedule of Activities – 
updated Tables 6 and 7 to reflect 
change in 3M and 6M study visit 
windows from “+6 wks” to “+8 wks”.   
• 
Section 9 – Statistical Analysis Plan 
and Sample Size - Section 9.1 Sample 
Size Determination – updated numbers 
for randomized population, APOL1 
positive assumed percentage, numbers 
of population that would be in each arm 
for main study and PGx substudy. 
Updated Tables 8 and 9. Changed 
power for PGx substudy from 80% to 
90%. 
• 
Section 9.1 Sample Size Determination 
– added “Enrollment may end prior to 
the 6650 target if the study team notes 
that the necessary 931 APOL1 positive 
individuals 
have 
already 
been 
enrolled.” 
• 
Section 9.7 Interim Analyses – added 
language describing how additional 
interim analyses would be handled if 
requested by the DSMB. 
• 
Sections 6, 7 &10 – removed “to be” 
from “to be provided in the MOP”. 
5 
 
 
Title 
Page; 
Protocol Version and 
Amendment 
Tracking; Investigator 
Statement; 
List 
of 
Tables; 
Protocol 
Synopsis; Sections 2, 
3, 4, 5, 7, 8, 9, 10 and 
11 
• 
Title Page and Investigator Statement 
• 
Protocol Version and Amendment 
Tracking – added Amendment 5 
change information  
• 
List of Tables – removed Tables 8 & 9  
• 
Protocol 
Synopsis 
– 
changed 
“Appropriate” to “Documented” under 
objectives and secondary endpoints; 
clarified PGx substudy participants by 
including 
information 
regarding 
participating 
sites; 
changed 
randomized 
population 
to 
6,750; 
clarified inclusion criteria “allogenic” as 
added before bone marrow (previously 
approved 
on 
04-Nov-2022 
in 
clarification memo #4); added “an 
19Mar2024 

 
7 
 
overall” under Statistical Analyses; 
changed “All” to “Major” and removed 
“and 
secondary” 
under 
Substudy 
Analyses. 
• 
Section 2 – Introduction – changed “≤” 
to “<” and changed “appropriate” to 
“documented” for CKD diagnosis.  
• 
Section 3.2 – Secondary Endpoints – 
Changed 
“appropriate” 
to 
“documented” 
under 
secondary 
endpoints 2, 3, 4, 5, and 6. 
• 
Section 4 – Study Design – clarified 
PGx substudy population by including 
information 
regarding 
participating 
sites; updated numbers for randomized 
population, APOL1 positive assumed 
percentage, and numbers of population 
that would be in each arm for main 
study and PGx substudy and clarified 
rationale for updated target; added 
“approximately” before 90% power. 
• 
Section 5 – Study Population – clarified 
exclusion 
criteria 
by 
adding 
“allogeneic”. (previously approved on 
04-Nov-2022 in clarification memo #4) 
• 
Section 7.3 – Follow-Up Assessments 
– changed “6” to “8” consistent with 
extended window approved in Jul 2022.  
• 
Section 7.7 – Data Collected from the 
Electronic Health Record – changed “in 
the 6 months” to “up to 8 months” 
(previously approved on 14-Feb-2024 
in clarification memo #5) 
• 
Section 7.7 – Data Collected from the 
Electronic Health Record and Section 8 
– Safety Assessments and Monitoring – 
removed “two”, “one” and “another” 
from the EHR downloads sentence.  
(previously approved on 14-Feb-2024 
in clarification memo #5) 
• 
Section 9 – Statistical Analysis Plan 
and Sample Size – updated numbers 
for randomized population, APOL1 
positive assumed percentage, numbers 
of population that would be in each arm 
for main study and PGx substudy; 
added additional information regarding 
continued enrollment until effect size is 
reached; 
removed 
sentences 

 
8 
 
“Additional calculations using the same 
assumptions…and 
BP 
standard 
deviation”; removed table 8; removed 
“interim analysis” from PGx substudy; 
added “approximately” before 90% 
power for PGx substudy; removed 
sentences 
“Additional 
calculations 
using the assumptions…major cardiac 
outcomes”; removed table 9; clarified 
population for PGx substudy; added 
“overall” before two-sided for primary 
endpoint 
analysis; 
changed 
“appropriate 
to 
“documented” 
for 
secondary endpoint analysis;  updated 
potential covariates by adding “and 
baseline CKD” and removing “income, 
education, 
marital 
status, 
and 
insurance, and Charlson comorbidity 
index”; updated “above 140 mm Hg” to 
“140 mm Hg or greater”; added 
“depending on the outcome of the main 
study” and removed “body mass index” 
from 
Cost-Effectiveness 
section; 
removed “all” form pGx substudy 
analyses section; added “Impact of 
Social Determinants of Health” under 
Other Planned Analyses; updated 
Interim Analyses section to describe a 
second interim analysis and impact on 
p-value.  
• 
Section 10 – Data Management – 
Clarified definitions of baseline and 
follow-up SBPs; Updated CPT codes; 
added “OR the presence of urine 
microalbuminuria/proteinuria lab test 
order and/or result”; removed “AND 
order 
of 
urine 
microalbuminuria/proteinuria test at 6 
months”; 
updated 
ICD-10 
codes; 
removed “AND appropriate diagnosis at 
6 months (as described in 3b)) under 4 
and 6”; added “YN” under 2, 4 and 6; 
removed “OR having hypertension in 
the patient’s medical record problem list 
in the 24 months prior to baseline] and 
[having 2 lab results of eGFR <=60 
ml/min 3 months apart with at least one 
test in the 24 months prior to baseline 
OR 
order 
of 
urine 
microalbuminuria/proteinuria test with 

 
9 
 
both eGFR and urine tests in the time 
period from 24 months prior to baseline 
to 6 months after baseline]” from 3 and 
5; 
changed 
“appropriate” 
to 
“documented” under 2, 3, 4, 5, and 6. 
• 
Section 11 – Ethical and Human 
Subjects Considerations – changed 
“recruiters at each site” to “the study 
team” and changed “and” to “or” in the 
phrase “de-identified and anonymized”.  
 
 
 

 
10 
 
 
INVESTIGATOR STATEMENT 
 
 
 
 
By signing below, I agree to the conditions relating to this trial as set out in this protocol (v6 dated 19Mar2024). 
 
I agree to conduct this clinical trial according to Good Clinical Practice (ICH GCP) and US Regulatory 
Requirements.  
 
I fully understand that any changes instituted by me without previous discussion with the IGNITE Pragmatic Trials 
Network Coordinating Center or their designated representative constitute a violation of the protocol.   
 
I agree to adhere to the protocol in all circumstances other than where necessary to protect the well-being of the 
participant. 
 
 
 
Principal Investigator’s  
 
Name: ___________________________________ 
 
 
Signature: __________________________     Date____________ 
 
 
 
 
 
 
 
 
 
 
 
 

 
11 
 
 
 
 
ABBREVIATIONS 
 
AA 
African Americans 
AE 
Adverse Event 
ACE 
Angiotensin-converting enzyme 
ARB 
Angiotensin receptor blocker 
APOL1 
Apolipoprotein L1 
BP 
Blood pressure 
CC 
Coordinating center 
CKD 
Chronic kidney disease 
CDS 
Clinical decision support 
CE 
Cost-effectiveness 
CEA 
Cost-effectiveness analysis 
CIOMS 
Council for International Organizations of Medical Sciences 
CLIA 
Clinical Laboratory Improvement Amendments 
CPT 
Current Procedural Terminology 
CRF 
Case Report Form 
DSMB 
Data and safety monitoring board 
eGFR 
Estimated glomerular filtration rate 
EHR 
Electronic Health Record 
ESRD 
End stage renal disease 
GUARDD-US 
Genetic Testing to Understand and Address Renal Disease 
Disparities across the US 
HIPAA 
Health Insurance Portability and Accountability Act of 1996 
HTN 
Hypertension 
IGNITE PTN 
Implementing Genomics in Practice Pragmatic Trials Network 
MOP 
Manual of operations 
NHGRI 
National Human Genome Research Institute 
PCT 
Pragmatic Clinical Trial 
PI 
Principal Investigator 
PGx 
Pharmacogenetic 
PPC 
Publications and Presentations Committee 
ROR 
Return of results 
SAP 
Statistical analysis plan 
SBP 
Systolic blood pressure 
SOP 
Standard operating procedure 
 
 
 

 
12 
 
 
LIST OF FIGURES 
 
Figure 1. GUARDD-US study design for sites participating in PGx. .......................................................... 23 
Figure 2. GUARDD-US study design for sites not participating in PGx. .................................................... 24 
 
 
LIST OF TABLES 
Table 1. APOL1 Laboratory Report Language ............................................................................................... 32 
Table 2. Genes and gene variants to be tested in the PGx substudy. ....................................................... 33 
Table 3. PGx genotypes, phenotypes, and predicted genotype frequencies. ........................................... 33 
Table 4. PGx recommendationsa ...................................................................................................................... 34 
Table 5. Schedule of participant activities up to randomization for sites. .................................................. 38 
Table 6. Schedule of activities following participant baseline visit for sites participating in the PGx 
substudy. ............................................................................................................................................................... 39 
Table 7. Schedule of activities following participant baseline visit for sites participating not in the PGx 
substudy. ............................................................................................................................................................... 40 
Table 8. ICD10 diagnosis codes and descriptions for diabetes .................................................................. 56 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
13 
 
TABLE OF CONTENTS 
1. PROTOCOL SYNOPSIS 
16 
2. INTRODUCTION 
20 
2.1 
Background, Significance, and Rationale 
20 
2.2 
Aims and Objectives of the Study 
21 
3. ENDPOINTS 
22 
3.1 
Primary Endpoint 
22 
3.2 
Secondary Endpoints 
22 
3.3 
Pharmacogenetic (PGx) Substudy Endpoints 
22 
4. STUDY DESIGN 
23 
4.1 
Study Arms & Design 
23 
4.2 
Randomization 
24 
4.3 
Blinding 
25 
4.4 
Sample Size 
25 
5. STUDY POPULATION 
26 
5.1 
Inclusion Criteria 
26 
5.2 
Exclusion Criteria 
27 
6. RECRUITMENT AND ENROLLMENT PROCEDURES 
28 
6.1 
Provider Recruitment, Assent, and Consent 
28 
6.2 
Participant Recruitment Strategies 
28 
6.3 
Screening Procedures 
28 
6.4 
Participant Consent Process 
29 
6.5 
Participant Discontinuation/Withdrawal from the Study 
29 
6.6 
Lost to Follow-Up 
29 
6.7 
Risk 
29 
6.8 
Benefit 
30 
6.9 
Costs to the Participants 
30 
6.10 
Compensation to Participants 
30 
7. STUDY PROCEDURES 
31 
7.1 
Interventions/Treatments 
31 
7.2 
Baseline Assessments 
34 
7.3 
Follow-Up Assessments 
35 
7.4 
Specimen Collection 
35 

 
14 
 
7.5 
Specimen Transfer and Genetic Testing Procedures 
36 
7.6 
Return of Genetic Results 
36 
7.7 
Data Collection from the Electronic Health Record 
36 
7.8 
Clinical Decision Support System 
37 
7.9 
Provider Surveys 
37 
7.10 
Schedule of Activities 
37 
8. SAFETY ASSESSMENT AND MONITORING 
41 
8.1 
Distress from Return of Results 
41 
8.2 
Events of Interest 
41 
8.3 
Safety Monitoring/Data and Safety Monitoring Board 
41 
8.4 
Early Termination and Participant Discontinuation 
41 
9. STATISTICAL ANALYSIS PLAN AND SAMPLE SIZE 
42 
9.1 
Sample Size Determination 
42 
9.2 
General Statistical Methods 
43 
9.3 
Population for Analyses 
43 
9.4 
Analysis of the Primary Endpoint 
43 
9.5 
Analysis of the Secondary Endpoints 
43 
9.6 
Other Planned Analyses 
43 
9.7 
Interim Analyses 
45 
9.8 
Handling of Missing Data 
46 
9.9 
Multiplicity 
46 
10. 
DATA MANAGEMENT 
47 
10.1 
Data Entry and Record Keeping 
47 
10.2 
Data Element Definitions 
47 
10.3 
Database Management and Quality Control of Data 
49 
10.4 
Study Close Out 
49 
11. 
ETHICAL AND HUMAN SUBJECTS CONSIDERATIONS 
50 
11.1 
Institutional Review Board/Ethics Committee Review 
50 
11.2 
Use and Disclosure of Protected Health Information 
50 
11.3 
Confidentiality and Privacy 
50 
11.4 
Publication and Data Sharing Policies 
50 
12. 
PROTOCOL DEVIATIONS 
52 
13. 
CONFLICT OF INTEREST 
53 

 
15 
 
14. 
REFERENCES 
54 
15. 
APPENDICES 
56 
15.1 
Appendix A. Diabetes Diagnosis Codes 
56 
15.2  
Appendix B. PGx Substudy Gene Description and Evidence 
76 
 
 
 

 
16 
 
1. 
PROTOCOL SYNOPSIS 
Protocol Title 
Genetic testing to Understand and Address Renal Disease Disparities across the 
United States (GUARDD-US) 
Product/Intervention 
Immediate versus delayed return of Apolipoprotein L1 (APOL1) gene testing 
results to provider and participant. 
Objectives: 
The primary aim is to determine the effect of participant and provider knowledge of 
a positive APOL1 status on change in systolic blood pressure (SBP) from baseline 
to 3 months after randomization. Secondary aims are to: 
1. Determine the effect of participant and provider knowledge of a positive 
APOL1 status on the probability of documented chronic kidney disease 
(CKD) diagnosis. 
2. Determine the effect of participant and provider knowledge of a positive 
APOL1 status on the probability of receiving a urine test for CKD. 
3. Explore cost effectiveness, mediators, moderators, psychobehavioral 
impact of results disclosure on participants, and effects of knowledge of 
APOL1 status on provider treatment recommendations. 
 
PGx Substudy:  
GUARDD-US will include a substudy to determine the effect of knowledge of genetic 
test results that predict efficacy of various antihypertensive medications on change 
in SBP from baseline to 3 months in APOL1 negative individuals. 
Study Design 
Study Design: 
GUARDD-US is a prospective, multicenter, unblinded, two arm randomized 
pragmatic clinical trial. Participants will be randomized in a 1:1 ratio to immediate 
APOL1 gene testing and return of results (ROR) to participant and provider 
(Intervention arm) versus delayed APOL1 gene testing and ROR to participant and 
provider (Control arm). The main study will compare outcomes between APOL1 
positive participants in the Intervention arm (i.e., early knowledge of APOL1 status) 
to APOL1 positive participants in the Control arm (i.e., delayed knowledge of APOL1 
status). Participants that are APOL1 negative in the Intervention and Control groups 
will not be included in the main study analyses.    
 
Pharmacogenetic (PGx) Substudy Design: 
GUARDD-US will also include a substudy that randomizes participants in the 
Intervention arm who are from the PGx substudy participating sites and who test 
negative for APOL1 to PGx Intervention (i.e., immediate PGx ROR) and PGx Control 
(i.e., delayed PGx ROR) in a 1:1 ratio. This substudy will compare outcomes 
between participants in the PGx Control group and the PGx Intervention group. 
Rationale for Study 
Design 
High-risk variants in the APOL1 gene explain approximately 70% of the excess 
prevalence of CKD in African Americans (AAs), conferring a 5 times higher risk for 
hypertensive CKD and a 10 times higher risk for ESRD. A recent pilot study 
(GUARDD), showed that returning APOL1 gene test results had a statistically 
significant improvement in SBP at 3 months when comparing APOL1 positives to 
APOL1 negatives who received their genetic testing results and when comparing 
APOL1 positives that received their results early to overall controls who did not 
receive their results until after the 3 month visit. GUARDD was not however 
powered to evaluate the effects of having and knowing a positive APOL1 status on 
outcomes for those with high risk of developing CKD (i.e., comparing outcomes for 

 
17 
 
APOL1 positive patients who know their genetic risk to APOL1 positive patients 
who do not know their genetic risk). A broader trial is needed to better determine 
the importance of APOL1 gene testing for improving the testing, diagnosis, and 
treatment of individuals at risk of CKD. 
 
PGx Substudy: 
New data show that genetic differences may cause patients to respond differently 
antihypertensive medication therapy, particularly in AAs. Pharmacogenomics may 
help guide initial or add-on antihypertensive therapy management. However, the 
impact of PGx testing on BP has not been studied in clinical trials among general or 
AA populations.  
 
Study Population 
Randomized Population: 
Approximately 6,750 participants of African ancestry age 18-70 with hypertension 
that either: 1) do not have diabetes and do not have CKD, or 2) have CKD (with or 
without diabetes).  
 
Population for Main Study: 
Participants from Randomized Population (above) who test positive for APOL1  
 
Population for PGx Substudy: 
Participants from Randomized Population (above) randomized to Intervention and 
who test negative for APOL1. Only participants from PGx substudy participating 
sites are included in this population.  
Number of 
Recruitment Sites 
~46-60 
Duration of 
Participation 
~6 months for study visits, up to 12 months for EHR data retrieval 
Description of 
implementation of 
intervention (e.g., 
dose, schedule, etc.) 
The primary intervention for GUARDD-US is the immediate return of APOL1 genetic 
testing results to participants and participant providers. Return of APOL1 genetic 
testing results to participants and providers will occur as described in Section 7.6. 
In addition to verbal ROR, participants will also receive lay explanations in writing 
and an educational booklet explaining their results and genetic risks. Providers will 
be notified of participant results via standard site-specific laboratory return of results 
methods and, where possible, a clinical decision support system (CDS) within the 
electronic health system as described in Section 7.8. Providers may also receive 
links for accessing provider and participant educational materials through the CDS 
or other means. Finally, all participants are given the option to discuss their results 
with a genetic counselor.  
 
The intervention for the PGx substudy is the immediate return of PGx testing results 
to participants via phone and/or in-person, return of results and alerts via standard 
site-specific laboratory return of results methods and a CDS within the electronic 
health system for providers, and educational materials for both patients and 
providers regarding the genes tested and phenotypes associated with the efficacy 
of hypertension medications. 
Inclusion/Exclusion 
Criteria 
Inclusion Criteria: 
● Self-reported African ancestry 
● English Speaking 

 
18 
 
● Age 18-70 years 
● Have diagnosis of hypertension  
o Diagnosis of hypertension is defined by either: 
⮚ ICD10 diagnosis codes (i.e., I10; I11.x; I12.x; I13.x; I16.x) 
OR 
⮚ On active antihypertensive therapy for indication of 
hypertension OR 
⮚ Having systolic blood pressure of 140 mm Hg or greater in 
at least 2 of the last 3 consecutive recorded values in the 
EHR OR 
⮚ Having hypertension in the patient’s medical record problem 
list 
● Have been seen at ≥1 time in past year at a participating primary care site  
● Either: 1) do not have diabetes and do not have CKD, or 2) have CKD; 
Participants with diabetes may be included as long as they also have CKD. 
o CKD is defined by:  
⮚ ICD10 codes (i.e., N18.x; E08.22; E09.22; E10.22; E11.22; 
E13.22 (exclude Z94.0; N18.6; Z99.2)) OR 
⮚ Microalbumin/proteinuria level >30 mg/g for 2 time periods ≥ 
3 months. Values taken within 12 months of enrollment, 
unless 2 values are unavailable, then review within 24 
months of enrollment OR 
⮚ 15 ≤ eGFR ≤ 60 ml/min for 2 time periods ≥ 3 months 
o Diabetes is defined by: 
⮚ HbA1c ≥ 6.5 at least one time in the last year OR 
⮚ ICD10 diagnosis codes (see Appendix A) OR 
⮚ Having diabetes in the patient’s medical record problem list 
 
Exclusion Criteria 
● Have diabetes, but no CKD. 
● Are currently on dialysis (ICD 10 codes N18.6, Z99.2 and Z94.0) 
● Have ESRD (eGFR<15 ml/min)  
● Have a left ventricular assist device (LVAD) 
● Have a terminal illness (specifically metastatic cancer, palliative care or 
hospice) 
● Have patient-reported known pregnancy at time of enrollment 
● Have had a liver, kidney, or allogeneic bone marrow transplant 
● Too cognitively impaired to provide informed consent and/or complete the 
study protocol 
● Institutionalized or too ill to participate (i.e. incarcerated, psychiatric or 
nursing home facility) 
● Plan to move out of the area within 6 months of enrollment 
● Not a current patient seeing a provider who cares for their hypertension 
(i.e., family medicine, internal medicine, nephrology, HIV provider, 
cardiology, hypertension specialists) at a participating site 
● Previously participated in the GUARDD pilot study OR have previously 
undergone APOL1 testing 

 
19 
 
Primary Endpoint 
Change in Systolic Blood Pressure (SBP) from baseline to 3 months for APOL1 
positive participants.  
Secondary 
Endpoints 
The secondary endpoints for the main study include: 
● Change in urine microalbuminuria/proteinuria orders from baseline to 6 
months (Y/N) 
● Documented order of microalbuminuria/proteinuria tests by 6 months (Y/N)  
● Change in documented diagnosis for stage 3 CKD and above from 
baseline to 6 months (Y/N) 
● Documented diagnosis of CKD stage 3 and above by 6 months (Y/N) 
● Change in documented diagnosis for any stage CKD from baseline to 6 
months (Y/N) 
● Documented diagnosis of all stages of CKD by 6 months (Y/N)   
 
The major endpoint for the PGx substudy is the change in systolic blood pressure 
from baseline to the 3 month study visit.  
 
Statistical Analyses 
Main Study Analyses: 
● To determine the effect of participant and provider knowledge of a positive 
APOL1 status on SBP, we will compare the change in SBP from baseline 
to 3 months of the Intervention – APOL1 positive group to the change in 
SBP from baseline to 3 months of the Control - APOL1 positive group 
using a two sided t-test, as appropriate, with an overall two-sided type I 
error of 0.05.  
● The effect of knowledge of a positive APOL1 status on all secondary 
endpoints will be compared between Intervention - APOL1 positives to 
Control - APOL1 positives with the proportion difference test. 
● Additional analyses will include analysis of time trends in SBP, subset 
analyses, and exploratory analyses of cost effectiveness, mediators, 
moderators, psychobehavioral impact of results disclosure on participants, 
and effects of knowledge of APOL1 status on provider treatment 
recommendations. 
 
Substudy Analyses: 
● Major primary endpoint analyses conducted for the APOL1 main study will 
be repeated for the PGx substudy focusing on differences in outcomes 
between APOL1 negative individuals with immediate PGx ROR (PGx 
Intervention) and APOL1 negative individuals with delayed PGx ROR (PGx 
Control). 
 

 
20 
 
2. 
INTRODUCTION  
2.1 
Background, Significance, and Rationale 
Chronic kidney disease (CKD) is associated with hypertension and diabetes and affects 26 million US adults.1 
African Americans (AA’s) have higher risk of end stage renal disease (ESRD) necessitating maintenance dialysis 
or transplant than Whites.2 This disparity widens as kidney function declines. Additionally, AAs have the highest 
prevalence of hypertension (41% AA, 28% White) and the lowest rate of blood pressure (BP) control (43% AA 
versus 53% White).3 While improved BP control decreases CKD progression and reduces morbidity and mortality, 
BP control (defined as < 140/90 mm Hg4-7) is only achieved in 50% of participants.8  
 
One in 7 AAs carry the Apolipoprotein L1 (APOL1) gene risk allele, but it is nearly absent in other populations. 
High-risk variants in the APOL1 explain approximately 70% of the excess prevalence of CKD in AAs, conferring 
a 5 times higher risk for hypertensive CKD and a 10 times higher risk for ESRD.9 This risk is conferred by two 
variants (G1 and/or G2) in the last exon of APOL1 with the high-risk genotype being G1/G1; G2/G2 or G1/G2.10 
APOL1 does not significantly increase CKD risk in hypertensive people with diabetes and normal renal function, 
but in hypertensive people with prevalent CKD, APOL1 exacerbates worsening of kidney function and 
progression to ESRD regardless of diabetes diagnosis.11 Among adults with CKD, specific medications 
(angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs)) are recommended for 
participants of all ancestries, but 50% of participants do not receive these medications. Compounding this issue 
is the fact that providers do not include CKD on the problem list of 40% of participants with lab evidence of CKD,12 
leading to widespread participant unawareness of CKD. Urine protein tests, essential for early diagnosis and 
prognosis of CKD, are missing in up to 30% of participants with CKD.13  
 
In Genetic Testing to Understand Renal Disease Disparities (GUARDD), investigators randomized participants 
to immediate (Intervention) versus delayed (Control) APOL1 testing. Results were returned to participants 
through culturally appropriate clinical coordinators trained by genetic counselors, and to providers through low-
intensity clinical decision support (CDS) (including best practice alerts (BPAs) with the test results and links to 
more provider information, participant education, and a generic message about the importance of blood pressure 
control). The study included a narrower phenotype of participants, excluding those with CKD or diabetes. 
GUARDD showed a statistically significant reduction in SBP at 3 months when comparing: 1) APOL1 positives 
and negatives in the Intervention group (-6±18 mm Hg vs -3±18 mm Hg, p=0.008 cross-sectional at 3 months), 
and 2) Intervention APOL1 positives versus overall Controls (-6±18 mmHg vs -3±18 mmHg, p=0.04 cross-
sectional at 3 months).  GUARDD also showed a trend towards a higher proportion of participants receiving renal 
disease testing at 12 months, as captured through electronic health records, when comparing: 1) APOL1 positives 
and negatives in the Intervention group (29% vs 24%, p=0.10 cross-sectional at 12 months), and 2) Intervention 
APOL1 positives versus overall Controls (29% vs 20%, p=0.01 cross-sectional 12 months). Participants self-
reported making lifestyle changes and taking more blood pressure medicines in response to positive versus 
negative APOL1 results. In addition, over 95% of participants were satisfied with the type, timing, and amount of 
information they received. Although participants were offered the option to speak with or meet with a genetic 
counselor, none chose to do so. Using stakeholder-engaged processes, there was an 11% rate of refusal, 93% 
3-month retention rate, and 88% 12-month retention rate. 
 
Several new developments highlight the importance of a broader pragmatic clinical trial (PCT). The GUARDD 
study was not powered to compare those with high risk genotypes (APOL1 positives) in the Intervention group to 
APOL1 positives in the Control group. New evidence since the study’s inception also allows investigators to make 
CDS tools more robust, which may lead to greater action on the part of providers to improve hypertension 
management and renal disease screening. Finally, new data show that genetic differences affect the response 
to antihypertensive medication therapy, particularly in AAs. While pharmacogenetic (PGx) testing may help guide 

 
21 
 
initial or add-on antihypertensive therapy management for patients with hypertension, the impact of PGx testing 
on BP has not been studied in clinical trials among general or AA populations.  
2.2 
Aims and Objectives of the Study 
Because AAs are not routinely screened for APOL1, it is unknown whether participant or provider knowledge of 
genetic risk impacts participant care or outcomes. Accordingly, the main objective of GUARDD-US is to 
determine the effect of participant and provider knowledge of a positive APOL1 status on BP, urine testing for 
CKD, and documented diagnosis of CKD.  
  
The primary aim is to determine the effect of participant and provider knowledge of a positive APOL1 status and 
accompanying guideline based clinical decision support (CDS) on blood pressure management on change in 
systolic blood pressure (SBP) from baseline to 3 months after randomization among the APOL1 positive 
participants. Secondary aims are to: 
1. Determine the effect of participant and provider knowledge of a positive APOL1 status on the probability 
of documented CKD diagnosis. 
2. Determine the effect of participant and provider knowledge of a positive APOL1 status on the probability 
of receiving a urine microalbumin/creatinine testing and ACE-I/ARB prescription based on results of the 
urine microalbumin level. 
3. Explore cost effectiveness, mediators, moderators, psychobehavioral impact of results disclosure on 
participants, and effects of participant and provider knowledge of APOL1 status on provider treatment 
recommendations. 
 
In addition, GUARDD-US will include a substudy to determine the effect of knowledge of genetic test results that 
predict efficacy of various antihypertensive medications on change in SBP from baseline to 3 months in APOL1 
negative individuals. 
 

 
22 
 
3. 
ENDPOINTS 
3.1 
Primary Endpoint 
The primary endpoint is the change in systolic blood pressure from baseline to the 3 month study visit in APOL1 
positive participants.  
3.2 
Secondary Endpoints 
Secondary endpoints include: 
 
1. Change in urine microalbuminuria/proteinuria orders from baseline to 6 months (Y/N) 
2. Documented order of microalbuminuria/proteinuria tests by 6 months (Y/N)  
3. Change in documented diagnosis for stage 3 CKD and above from baseline to 6 months (Y/N) 
4. Documented diagnosis of CKD stage 3 and above by 6 months (Y/N) 
5. Change in documented diagnosis for any stage CKD from baseline to 6 months (Y/N) 
6. Documented diagnosis of all stages of CKD by 6 months (Y/N)   
 
Please see Section 10.2 for the derivations of these endpoints. 
3.3 
Pharmacogenetic (PGx) Substudy Endpoints 
The major endpoint for the PGx substudy is the change in systolic blood pressure from baseline to the 3 month 
study visit.  
 
Additional exploratory endpoints and analyses for the PGx substudy will be described in a separate Statistical 
Analysis Plan (SAP). 
 

23 
4.
STUDY DESIGN
4.1
Study Arms & Design
This is a prospective, multicenter, unblinded, two arm, randomized pragmatic clinical trial (PCT) (Figure 1). 
Participants will be recruited from several recruitment sites (hereafter referred to as site) and randomized in a 1:1 
ratio to immediate APOL1 gene testing and return of results (ROR) to participant and provider (Intervention arm) 
versus delayed APOL1 gene testing and ROR to participant and provider (Control arm). The main study will 
compare outcomes in a subset of the randomized population: APOL1 positive participants in the Intervention arm 
(i.e., early knowledge of APOL1 status) versus APOL1 positive participants in the Control arm (i.e., delayed 
knowledge of APOL1 status) (red outline in Figure 1). Participants that are APOL1 negative in the Intervention 
and Control groups will not be included in the main study analyses.   
Figure 1. GUARDD-US study design for sites participating in PGx.
The primary outcome of the main study is systolic blood pressure (SBP) at 3 months in Control-APOL1 positive and 
Intervention-APOL1 positive participants (red outline). The substudy outcome is SBP at 3 months in Intervention-APOL1

24 
Negative PGX Control and PGx Intervention participants (orange outline). AA = African Americans. APOL1 = Apolipoprotein 
L1. HTN = hypertension. PGx = Pharmacogenetics. ROR = Return of Results.  
GUARDD-US will also include a substudy that randomizes participants in the Intervention arm who test negative 
for APOL1 to PGx Intervention (i.e., immediate PGx ROR) and PGx Control (i.e., delayed PGx ROR) in a 1:1 
ratio. Only participants from the PGx substudy participating sites are included in this substudy. This substudy will 
compare outcomes between participants in the PGx Control group and the PGx Intervention group (orange outline 
in Figure 1). 
The study design for sites that are not participating in the PGx substudy is summarized in Figure 2.
  
Figure 2. GUARDD-US study design for sites not participating in PGx. 
The primary outcome of the main study is systolic blood pressure (SBP) at 3 months in Control-APOL1 positive and 
Intervention-APOL1 positive participants (red outline). AA = African Americans. APOL1 = Apolipoprotein L1. HTN = 
hypertension. ROR = Return of Results.  
4.2
Randomization
Eligible participants will be randomized in a 1:1 allocation to Intervention (i.e., immediate APOL1 gene testing 
and ROR to participant and provider) and Control arms (delayed APOL1 gene testing and ROR to participant and 
provider). Randomization will be stratified by clinical site with a random block size within site.  

 
25 
 
Participants that are randomized to receive immediate APOL1 ROR will simultaneously be randomized to the 
PGx substudy intervention (i.e., immediate PGx gene testing and ROR to participant and provider) or the PGx 
control (delayed PGx gene testing and ROR to participant and provider) using a 1:1 allocation ratio. Participants 
from PGx substudy participating sites that test negative for APOL1 will proceed into the PGx substudy under their 
assigned PGx treatment arms, while participants from non-participating sites of the substudy and participants 
that test positive for APOL1 will be excluded from the substudy and receive delayed PGx gene testing and ROR. 
4.3 
Blinding 
GUARDD-US randomization assignments will not be blinded to any participants, providers or study personnel 
because: 1) it is impossible to mask participants from the intervention testing and ROR, 2) research staff often 
receive questions from participants about the interpretation and risk associated with the participant’s genetic 
results during the administration of surveys, and 3) resource limitations make hiring additional blinded staff to 
measure blood pressure impractical. To minimize bias in the measurement of the primary outcome, 
randomization assignments will only be revealed after baseline survey responses and blood pressure readings 
have been collected, digital blood pressure devices (such as Professional Intellisense Blood Pressure Monitor 
OMRON-90714) will be used to measure blood pressure, and blood pressure will be measured as the mean of 
the second and third blood pressure readings for each participant at each visit. Manual blood pressures may be 
collected if necessary. 
4.4 
Sample Size 
Main Study:  GUARDD-US will randomize approximately 6750 individuals with approximately 3375 individuals in 
the Control Arm and 3375 in the Intervention arm. Assuming a 14% prevalence of APOL1 positive individuals, a 
sample size of 6700 for the randomized population would result in 938 APOL1 positive individuals with at least 
469 in each arm for the main study population. This sample size will detect a 3.5 mm Hg difference in the change 
in SBP between baseline and 3 months between Intervention - APOL1 positive and Control - APOL1 positive 
groups with 80% power. Since APOL1 result data and SBP change data could be missing for various reasons, 
an approximately 50 individuals will be randomized in addition to the 6700 sample size. Therefore, the total 
randomization target is approximately 6750. Please see Section 9.1 for assumptions, clinical significance, and 
detailed power and sample size calculations. 
 
PGx Substudy: Of the approximately 6750 participants in the GUARDD-US study, approximately 4400 will also 
be at a site participating in the PGx substudy. A sample size of 4400 with a 14% prevalence of APOL1 positive 
individuals would result in 1892 participants for the PGx substudy (Intervention – APOL1 negative participants) 
with 946 participants in the PGx Control and PGx Intervention arms. This sample size will detect a 3.1 mm Hg 
difference in the change in SBP from baseline to 3 months between the PGx Intervention group and PGx Control 
group with approximately 90% power. Please see Section 9.1 Sample Size Determination for assumptions, 
clinical significance, and detailed power and sample size calculations. 
 
 
 
 
 
 
 
 
 
 
 

 
26 
 
5. 
STUDY POPULATION 
5.1 
Inclusion Criteria 
● Self-reported African ancestry 
● English Speaking 
● Age 18-70 years 
● Have diagnosis of hypertension  
o Diagnosis of hypertension is defined by either: 
⮚ ICD10 diagnosis codes (i.e., I10; I11.x; I12.x; I13.x; I16.x) OR 
⮚ On active antihypertensive therapy for indication of hypertension OR 
⮚ Having systolic blood pressure of 140 mm Hg or greater in at least 2 of the last 3 
consecutive recorded values in the EHR OR 
⮚ Having hypertension in the patient’s medical record problem list 
● Have been seen at ≥1 time in past year at a participating primary care site  
● Either: 1) do not have diabetes and do not have CKD, or 2) have CKD; Participants with diabetes may 
be included as long as they also have CKD. 
o CKD is defined by:  
⮚ A) ICD10 codes (i.e., N18.x; E08.22; E09.22; E10.22; E11.22; E13.22 (exclude Z94.0; 
N18.6; Z99.2)) OR 
⮚ B) Microalbumin/proteinuria level >30 mg/g for 2 time periods ≥ 3 months. Values taken 
within 12 months of enrollment, unless 2 values are unavailable, then review within 24 
months of enrollment. 
1)      If there is only 1 proteinuria in E.H.R. (or if there are multiple and they are all within 
3 months), any single proteinuria/microalbuminuria >30 mg/g would qualify 
2)      If there are two or more proteinuria measures in E.H.R. that are at least 3 months 
apart AND are >30 mg/g would qualify 
a.       Even if there are multiple proteinuria measures in the E.H.R., and only two 
of them are >30 mg/g, but they are separated by at least 3 months would qualify 
b.      If there is only 1 proteinuria measure >30 mg/g and there are 2 or more 
proteinuria measures separated by 3 months within the prior 12 months would not 
qualify 
3)      If there are not 2 proteinuria measures in 12 months, review within 24 months of 
enrollment. 
OR  
⮚ C) 15 ≤ eGFR ≤ 60 ml/min for 2 time periods ≥ 3 months 
GFRs are taken within 12 months of enrollment, unless 2 values are unavailable, then 
review within 24 months. 
1)      If there is only 1 GFR in E.H.R. (or if there are multiple and are all within 3 months), 
any single GFR between 15-60 would qualify 
2)      If there are two or more GFRs in E.H.R. that are at least 3 months apart AND are 
between 15-60 would qualify 
a.       Even if there are multiple GFRs in the E.H.R., and only two of them are 
between 15-60, but they are separated by at least 3 months would qualify 
b.      If there is only 1 GFR between 15-60 and there are 2 or more GFRs 
separated by 3 months within the prior 24 months would not qualify 
3)      If there are not 2 GFRs in 12 months, review within 24 months. 
o Diabetes is defined by: 
⮚ HbA1c ≥ 6.5 at least one time in the last year OR 

 
27 
 
⮚ ICD10 diagnosis codes (see Table 10, Appendix A) OR 
⮚ Having diabetes in the patient’s medical record problem list 
5.2 
Exclusion Criteria 
● Have diabetes, but no CKD. 
● Are currently on dialysis (ICD 10 codes N18.6, Z99.2 and Z94.0) 
● Have ESRD (eGFR<15 ml/min)  
● Have a left ventricular assist device (LVAD) 
● Have a terminal illness (specifically metastatic cancer, palliative care or hospice) 
● Have patient-reported known pregnancy at time of enrollment 
● Have had a liver, kidney, or allogeneic bone marrow transplant 
● Too cognitively impaired to provide informed consent and/or complete the study protocol 
● Institutionalized or too ill to participate (i.e. incarcerated, psychiatric or nursing home facility) 
● Plan to move out of the area within 6 months of enrollment 
● Not a current patient seeing a provider who cares for their hypertension (i.e., family medicine, internal 
medicine, nephrology, HIV provider, cardiology, hypertension specialists) at a participating site 
● Previously participated in the GUARDD pilot study OR have previously undergone APOL1 testing 
 

 
28 
 
6. 
RECRUITMENT AND ENROLLMENT PROCEDURES 
6.1 
Provider Recruitment, Assent, and Consent 
Providers (including physicians, nurse practitioners, and provider assistants) that care for participants with 
hypertension (including, for example, general internists, family doctors/nurses, and nephrologists): 1) should be 
notified that their patients will be contacted to participate in the study, per site-specific institutional guidelines, and 
2) may be asked to participate in a baseline provider survey. Provider assent may be obtained as required per 
institutional guidelines. Site/clinical champions and GUARDD-US staff may present the study to providers at 
scheduled meetings and also in one-on-one encounters or email at various recruitment sites. Provider survey 
responses should be recorded in the study database. Study staff may send reminders to providers to increase 
survey completion rates.  
6.2 
Participant Recruitment Strategies 
Electronic Health Record (EHR) Data Queries for Eligible Participants 
Sites may query EHRs to identify potentially eligible participants using the inclusion/exclusion criteria (see the 
manual of operations (MOP) for further details).  
 
Participant Recruitment 
Participants may be approached for the study in various ways following local policies and procedures including, 
for example, recruitment letters mailed directly to patients, clinic intercepts, study flyers, clinic referrals, or directly 
in clinic during a regularly scheduled clinic appointment. Participant recruitment letters may be created according 
to site-specific institutional policies, including, for example, instructions for how to opt out of study participation. 
Research Coordinators can also approach potentially eligible patients at clinic appointments. Research 
Coordinators may also provide clinical staff with study referral cards with eligibility criteria and study contact 
information for patient referrals. Clinics may have posters, flyers, and advertisements on TV monitors in waiting 
rooms with a study description and Research Coordinator contact information. If a patient expresses interest in 
participating, Research Coordinators may use a recruitment script (provided in the MOP) to do an initial screen 
for eligibility and then schedule the baseline visit in the future or that same day. Study staff may also ask current 
participants if they know anyone who would qualify for the study and provide them with study-related contact 
information to share with others. 
 
Stakeholder Group and Additional Recruitment Materials 
Diverse groups of stakeholders consisting of patient advocates, clinicians and community leaders will be engaged 
throughout the study process. These will include the Sinai Genomics Board, the Implementing Genomics in 
Practice Pragmatic Trials Network (IGNITE PTN) Patient, Provider, and Payer Advisory Board, and where 
available, stakeholders from sites. They may meet regularly to review all patient facing materials, including 
consent forms and patient recruitment and educational materials (recruitment letters, scripts, flyers, posters, etc.), 
for clarity and content. They may also provide input on recruitment strategies, addressing study design and 
challenges.  
6.3 
Screening Procedures 
Research Coordinators may use a recruitment script (provided in the MOP) during recruitment phone calls or 
clinic intercepts (described above) to inform the potential participant about the study and screen participants for 
eligibility using the study inclusion/exclusion criteria. If the participant is eligible and interested, a baseline visit 
should be scheduled in the future or that same day. Screening may also be performed in a location agreed upon 
between a potential participant and the research team. 

 
29 
 
6.4 
Participant Consent Process 
If a participant is interested and eligible, Research Coordinators will review the consent document prior to 
enrolling the participant. Prospective research participants will have the opportunity to ask questions before 
providing written consent. Research Coordinators will provide the participant with a signed copy or version of the 
consent document. An original signed consent form is maintained by the Research Coordinator to be filed per 
site policies. If the individual chooses not to sign the consent form, the Research Coordinator will inform him/her 
they are unable to participate in the study. The consenting process can also be remote, via phone or electronically 
if approved by the reviewing IRB. A participant can complete the baseline visit and be randomized into the study 
within 30 days of providing written consent. If randomization does not occur within 30 days then this participant 
would be considered a screen failure.   
 
Research participants will also be informed that they may be given the option to participate in other studies and 
provide additional biological specimens or data for those studies, which will require separate informed consent. 
They will also be provided the option to have their data collected as part of this study stored and shared for future 
related research, according to site-specific institutional policies. 
 
6.5 
Participant Discontinuation/Withdrawal from the Study  
Participants may stop participating or withdraw from the study at any point in time. All information and data 
collected from the participant up to that point can be used in the study. Withdrawal of consent to participate in the 
research study can be verbal or in writing, however, revocation of HIPAA authorization must be in writing. 
Research Coordinators should attempt to obtain a reason for withdrawal from the participant and record it in the 
study database.  
6.6 
Lost to Follow-Up 
Losses to follow-up may be minimized and retention maximized through various mechanisms, including offering 
study visits during evening and weekend hours, collecting information for and contacting family members when 
participants cannot be reached, approaching research participants at clinic appointments, and completing surveys 
over-the-phone (although research participant should still attend study visits for blood pressure measurement). 
Certified letters may also be sent to those not reached by phone. Research Coordinators should confirm the best 
contact information for the participant at each study visit. Research Coordinators may also obtain permission to 
contact patients via text message or email and may send additional correspondence during the study. Participants 
may be assigned to a specific Research Coordinator at the site in order to maintain continuity and build rapport. 
6.7 
Risk 
This research presents minimal risks to participants. Possible risks are described below. 
 
Blood Pressure 
Participants may feel some arm pressure when the blood pressure cuff is briefly inflated. 
 
Blood Draw 
The risks of a blood draw include pain, bruising, and the slight possibility of infection at the location of needle 
insertion. Some participants may feel dizzy or may faint during or after a blood draw. 
 
Learning test results 
Results of blood, saliva, or buccal cell tests may show that a participant is at an increased risk of kidney disease. 
This knowledge may cause anxiety or psychological distress. Study staff should be trained to recognize anxiety 
and psychological stress and to attempt to relieve patient discomfort via discussion. All test results will be 

 
30 
 
discussed with the participant at the time of ROR. If systolic blood pressure exceeds 190 mm Hg or diastolic 
exceeds 110 mm Hg during any study visit, the participant will be strongly advised to seek urgent and appropriate 
evaluation and care from a healthcare provider. The Research Coordinator may facilitate this by assisting the 
participant in contacting their primary care provider, urgent care, or clinic staff on site including the Principal 
Investigator (if study visit is taking place in a clinical setting).   
 
Delay in Learning Test Results 
There is a risk that some patients in the Control group will have a 6 month delay in learning positive genetic test 
results relative to those in the Intervention group. Earlier knowledge of positive APOL1 status could improve 
patient care and health outcomes. However, because APOL1 testing is not currently considered standard care, 
the risks are low compared to patients receiving standard care. 
 
Genetic Discrimination 
While the Genetic Information Nondiscrimination Act (GINA), generally makes it illegal for health insurance 
companies, group health plans, and most employers to discriminate against participants based on their genetic 
information, federal law does not protect patients against genetic discrimination by companies that sell life 
insurance, disability insurance, or long-term care insurance. 
6.8 
Benefit 
Research participants may not directly benefit from taking part in this research.  However, some participants and 
their doctors may become aware of possible kidney disease earlier or which blood pressure medications are most 
efficacious. Providers may be able to make better decisions about the kind of treatment patients receive, thus 
providing some indirect benefit to participant health. 
6.9 
Costs to the Participants 
Taking part in this research study may lead to minor added costs including, for example, transportation to attend 
study visits. 
6.10 
Compensation to Participants 
Research participants will receive compensation throughout the course of the study for their time and effort. They 
will receive compensation for completion of each study visit – baseline, 3-month follow up, and 6-month follow 
up. Compensation may also be provided, on a pro-rated basis, for survey completion over the phone. Participants 
may be reimbursed for travel and/or parking expenses per institutional specific policies. 
 
 
 

 
31 
 
7. 
STUDY PROCEDURES 
This section provides an overview of the study procedures to be followed in GUARDD-US. Further details will be 
provided in a MOP. Sites will receive training on the protocol and MOP before beginning enrollment. 
7.1 
Interventions/Treatments 
The intervention for GUARDD-US is intended to reflect the practices and procedures that are likely to be 
implemented if APOL1 testing were to be integrated into standard clinical practice. It includes the following 
components for participants and providers:  
 
Participants 
● An educational booklet given to all participants at the baseline visit that includes information about high 
blood pressure, kidney disease, and APOL1 gene testing, and language recommending that participants 
speak with their provider if their BP is >130/80 mm Hg.  
● The results of participant blood pressure readings at each study visit including 
o the mean of the second and third blood pressure readings 
o an indication of whether the mean value is normal (<130/80 mm Hg), up to your provider 
(between 131/81 mm Hg and 140/90 mm Hg) or elevated (>140/90 mm Hg) 
o a recommendation to speak with a provider if the participant’s BP is above normal 
● The verbal return of APOL1 genetic testing results (i.e., APOL1 positive or negative) and a verbal 
explanation of the meaning of the genetic testing results for risk of CKD and hypertension to participants 
following the schedule of activities and procedures for the participant’s APOL1 randomization 
assignment (see Section 7.10). 
● A written explanation of the clinical implications of the patient’s APOL1 genetic testing results given to 
participants at the time of ROR. 
● The same educational booklet will be given to participants as a reminder at the time of ROR.  
● The option for patients to speak with a genetic counselor about their results.  
 
Providers 
● The electronic or written return of APOL1 genetic testing results (i.e., APOL1 positive or negative) to 
patient providers via standard site-specific laboratory return of results methods at approximately the 
same time or after participants have received their APOL1 genetic testing results. 
● Where possible, the electronic return of positive APOL1 gene testing results to providers via a CDS alert 
that includes the participant’s positive APOL1 status, the risks associated with the participant’s APOL1 
status, and treatment recommendations (including treatment for elevated BPs, ordering urine proteins 
tests, and ordering ACEs/ARBs) at approximately the same time or after participants have received their 
APOL1 genetic testing results (see Section 7.8 for details). 
● Educational materials explaining APOL1 gene testing and clinical implications may be given to providers 
at the same time or after they have received patient APOL1 genetic testing results. 
 
During the baseline visit, all participants should receive an educational booklet with information about high blood 
pressure, kidney disease, and APOL1 gene testing. This document will be identical for all participants. 
Participants will be notified of their APOL1 randomization assignment after completing the baseline visit. At the 
end of each study visit (i.e., baseline, 3 month, 6 month), all participants will also receive the results of their blood 
pressure readings including the mean of the second and third blood pressure readings and an indication of 
whether this measurement is normal (<130/80 mm Hg), up to your provider (between 131/81 mm Hg and 140/90 
mm Hg) or elevated (>140/90 mm Hg). Participants in the Control arm will receive their APOL1 genetic testing 
results and an explanation of the meaning of their genetic testing results for risk of CKD and hypertension by 
phone and/or in-person after their 6 month study visit, while participants in the Intervention arm will receive their 
APOL1 genetic testing results and an explanation of the meaning of their genetic testing results via phone and/or 

 
32 
 
in-person as soon as their results are available after the baseline visit. All participants will be given the option to 
speak to a genetic counselor as soon as results are returned. In addition to verbal ROR, participants will also 
receive lay explanations of their test results in writing and the educational booklet at the time of ROR in case the 
education booklet given at baseline was misplaced. These documents will be sent via mail and/or secure email 
to participants after the study team has attempted to verbally notify the participant of their test results. Written 
explanations of the test results and educational booklets will be identical for both Control and Intervention 
participants. In addition to study visits, participants may also have non-study related visits with their provider/s 
during the study. All participants may receive treatment recommendations or therapies for hypertension as part 
of these routine care visits.  
 
Providers may be notified of participant results via standard site-specific laboratory return of results methods and, 
where possible and for positive APOL1 results, a CDS alert within the electronic health system, as described in 
Section 7.8. Providers may also receive electronic links for accessing provider and participant educational 
materials through the CDS or other means. Providers of participants in the Intervention arm may receive 
notifications of the participants APOL1 gene status during the study (via CDS alert or standard site-specific 
laboratory return of results methods). Providers of participants in the Control arm may be notified of participant 
APOL1 gene status after the participant’s 6 month study visit. Details of the ROR are presented in Section 7.6 
and the schedule of activities is presented in Section 7.10. Table 1 describes the APOL1 variants and their 
predicted CKD risk.9  
 
 
Table 1. APOL1 Laboratory Report Language 
Gene 
Result 
Predicted Risk Status  
APOL1 
*G2/*G2 
Increased Risk of Chronic Kidney Disease 
Incidence and Progression  
*G1(GM) HET 
Standard Risk of Chronic Kidney Disease 
Incidence and Progression 
 
 
The intervention for the PGx substudy is also intended to reflect the practices and procedures that are likely to 
be implemented if PGx testing were to be integrated into standard clinical practice. It includes the following 
components for participants and providers:  
 
Participants 
● An educational booklet explaining PGx testing and clinical implications for hypertension medication 
management given to participants at the baseline visit. 
● The return of PGx genetic testing results to participants following the schedule of activities and 
procedures for the participant’s PGx randomization assignment. 
● A written explanation of clinical implications of the patient’s PGx genetic testing results including the 
genes tested and phenotypes associated with the efficacy of hypertension medications given to 
participants at the time of ROR. 
● An educational booklet given to participants at the time of ROR.  
 
Providers 
● The return of PGx genetic testing results to patient providers via standard site-specific laboratory return 
of results methods at approximately the same time or after participants have received their PGx testing 
results. 

 
33 
 
● Where possible, a CDS provider alert for actionable phenotypes when a relevant medication is or may 
be ordered that indicates the participant’s genetic results, the predicted phenotype (i.e., efficacy of 
various hypertension medications), and treatment recommendations at approximately the same time or 
after participants have received their PGx testing results. 
 
Tables 2 and 3 describe the genes, variants, and phenotypes for the PGx substudy. The PGx sub-study will 
examine the efficacy of providing genetic information for two gene-drug pairs. The first gene-drug pair is YEATS4 
and thiazide diuretic efficacy, and focuses on first-line antihypertensive therapy in African Americans. The second 
gene-drug pair is NAT2 and hydralazine. Hydralazine is not first line therapy, but is used in the treatment of 
resistant hypertension. GUARDD-US will include patients with both hypertension and resistant hypertension. 
Neither gene-drug pair is presently recommended by CPIC, but both have significant evidence supporting their 
relationship in populations that include individuals of African ancestry which is summarized in Appendix B.  
 
Table 4 describes the PGx recommendations to be given for actionable genotypes. Each recommendation will 
be provided in the laboratory return of results and via a CDS alert, where available, that will be activated when a 
provider prescribes a medication that is not recommended based on the participant’s genotype. Please see 
section 7.6 for more details. 
 
 
Table 2. Genes and gene variants to be tested in the PGx substudy. 
Gene 
Variant 
NAT2 
rs1801279, rs1801280, rs1799930, rs1799931 
YEATS4 
rs7297610 
 
 
 
Table 3. PGx genotypes, phenotypes, and predicted genotype frequencies. 
Gene 
Genotyping Result 
Predicted Phenotype 
Phenotype 
Frequency 
NAT2 
1 or more copy of *4 
Reduced Hydralazine Efficacy 
0.50 
NAT2 
2 copies of *5, *6, *7, *14b 
Increased Hydralazine Efficacy 
0.50 
YEATS4 
T/T or T/C 
Reduced Thiazide Efficacy 
0.51 
YEATS4 
C/C 
Standard Thiazide Efficacy 
0.49 
 
 
 

 
34 
 
 
Table 4. PGx recommendationsa 
Goal (Drug Class) 
Gene 
Genotype 
Recommendation 
First Line Therapy 
(Thiazide diuretic) 
YEATS4 
C/C 
This individual is predicted to have standard thiazide 
efficacy. Consider use of a thiazide diuretic or calcium 
channel blocker as first line treatment of hypertension. 
First Line Therapy 
(Thiazide diuretic) 
YEATS4 
TT or TC 
This individual is predicted to have reduced thiazide 
efficacy. Consider use of an alternate first line therapy 
such as a calcium channel blocker for treatment of 
hypertension. 
Resistant 
Hypertension 
(Hydralazine) 
NAT2 
*4/*X 
This individual is predicted to have reduced hydralazine 
efficacy and may require a 50-100% higher starting dose 
or an alternate agent such as clonidine, spironolactone, 
or doxazosin for resistant hypertension. 
Resistant 
Hypertension 
(Hydralazine) 
NAT2 
2 non-*4 
alleles 
This individual’s NAT2 genetic test result is associated 
with increased hydralazine levels, which may lead to 
increased efficacy and/or adverse effects. 
aDetailed references and rationale are summarized in Appendix B  
7.2 
Baseline Assessments 
At baseline, which may occur in a location agreed upon between potential participants and the research team, 
Research Coordinators will verify that the participant has given consent. If participant has not given consent, 
Research Coordinators will obtain consent and information for multiple methods of patient contact (including 
mailing address, all phone numbers, and next of kin contact information). Research Coordinators will administer 
a survey (approximately 30 minutes long) to obtain information regarding the demographics, comorbidities, 
psychosocial factors, and knowledge, attitudes and beliefs towards genomics, kidney disease and hypertension. 
Survey responses will be recorded by the Research Coordinator in the study database and may be administered 
over the phone. A paper version of the survey can be used during a study visit, with survey data entered into the 
study database at a later time. Blood pressure will be measured according to the GUARDD-US Blood Pressure 
Protocol (details provided in the MOP) using a digital blood pressure monitor (such as Professional Intellisense 
Blood Pressure Monitor, OMRON-90714). Manual blood pressures may be collected if necessary. Pulse 
measurement will also be recorded for each participant and a blood, saliva, or buccal cell sample will be collected 
(as described in Section 7.4). After completion of the baseline visit, the Research Coordinator will randomize 
participants to immediate or delayed APOL1 genetic testing and give patients: 1) an educational booklet with 
information about high blood pressure, kidney disease, and APOL1 gene testing, 2) the results of participant 
blood pressure readings including the mean of the second and third blood pressure readings and an indication 
of whether this measurement is normal (<130/80 mm Hg), up to provider (between 131/81 mm Hg and 140/90 
mm Hg) or elevated (>140/90 mm Hg), and 3) the participant’s randomization assignment.  
 
During the baseline visit, if the third (3rd) of three (3) consecutively measured blood pressure readings is greater 
than or equal to 190 mmHg for SBP or greater than or equal to 110 mmHg for DBP, study staff must inform the 
participant that they have very high blood pressure and strongly advise that they get urgent and appropriate 
evaluation and care from a healthcare provider. Study staff must also inform study PIs and follow the elevated 
blood pressure protocol outlined in the MOP. 
 

 
35 
 
Genetic sample collection and blood pressure measurement should occur on the same day and randomization 
must occur within 72 hours of blood pressure collection.  
7.3 
Follow-Up Assessments 
Participants enrolled in the study will meet with Research Coordinators in a location agreed upon between the 
participant and the research team for a baseline, 3 month, and 6 month study visit. Follow-up visits will be 
completed within 8 weeks after the projected follow-up date. At each follow-up visit, Research Coordinators will 
administer the study surveys to participants and record their responses, measure and record the participant’s 
blood pressure according to GUARDD-US Blood Pressure Protocol (provided in the MOP) and pulse 
measurement. Participants will be compensated for each study visit (see Section 6.10). Whenever possible, 
participants will meet with the same Research Coordinator for follow-up visits to maintain continuity. Follow-up 
assessments at each visit will include only participant-reported surveys, blood pressure and pulse measurements. 
Follow-up surveys may also be administered over the phone. 
 
If a study site has been unable to reach a participant for a follow up visit, a blood pressure measurement may be 
obtained from the EHR and recorded in the study database if it meets the following criteria: 1) the blood pressure 
was measured within the specified visit window for the missed projected visit date and 2) the visit was either a 
clinic visit or a hospital discharge. Within the projected follow-up window, the blood pressure reading that was 
collected closest to the survey completion date will be used.  
 
During any follow-up visit, if the third (3rd) of three (3) consecutively measured blood pressure readings is greater 
than or equal to 190 mmHg for SBP or greater than or equal to 110 mmHg, study staff must inform the participant 
that they have very high blood pressure and strongly advise that they get urgent and appropriate evaluation and 
care from a healthcare provider. Study staff must also inform study PIs and follow the elevated blood pressure 
protocol outlined in the MOP. 
 
7.4 
Specimen Collection 
 
At the baseline visit, Research Coordinators will consent participants if not previously consented, administer the 
baseline survey, take 3 blood pressure readings, and, obtain a genetic sample via blood draw, saliva or buccal 
cell collection, whichever is most appropriate for the site and if possible, participant preferences.  
 
Blood Draw Protocol 
A phlebotomist or a coordinator trained in phlebotomy should collect 1 tube (approximately 1-2 teaspoons or 5 
mLs) of blood via venipuncture from participants willing to give a blood sample. Research Coordinators should 
follow the MOP for instructions regarding the collection, storage, and delivery of the genetic samples to the 
designated laboratory.   
 
Saliva Protocol 
Alternatively, participants may provide a saliva sample in lieu of a blood sample. Research Coordinators should 
follow the MOP for instructions regarding the collection, storage, and delivery of the sample to the designated 
laboratory.  Patients giving a saliva sample should not eat, drink, smoke or chew gum for 30 minutes before 
sample collection. Previous studies have confirmed that saliva samples are a viable alternative as a source of 
DNA for genotyping procedures15. 
 
Buccal Cell Protocol 
Alternatively, participants may provide a buccal cell sample in lieu of a blood or saliva sample. Sample collection 
swabs/brushes should be labeled by recruiters, and collection, storage, and delivery to the designated laboratory 

 
36 
 
will follow the Buccal Cell Collection Protocol provided in the MOP. Participants providing a buccal cell sample 
should not eat, drink, smoke, or chew gum for 30 minutes before sample collection. 
7.5 
Specimen Transfer and Genetic Testing Procedures 
All collected specimens should be clearly marked with the participant ID and all other required fields according to 
the instructions in the MOP, and delivered to a designated laboratory. Samples from Intervention arm participants 
will be processed by the laboratory as soon as possible using analytically validated APOL1 and PGx gene testing 
procedures. For Control arm samples, designated laboratories will either extract DNA as soon as possible after 
sample receipt, and store the DNA for later analysis or store the sample and extract DNA after the Control 
participant has completed the 6 month follow-up assessment. Control Arm DNA samples will be processed as 
soon as possible after the 6 month visit using analytically validated procedures. Genes to be tested for the PGx 
substudy along with genotyping results and predicted phenotypes are described in Section 7.1. Details of sample 
storage and transport will be presented in the MOP. All laboratories in GUARDD-US are Clinical Laboratory 
Improvement Amendments (CLIA)-certified for high complexity.  
7.6 
Return of Genetic Results  
The designated laboratories will transfer participant genetic testing results to the IGNITE PTN Coordinating 
Center (CC) as soon as possible and follow standard site-specific procedures for return of results to providers. 
Genetic results will be imported into the study database and the site EHR, where available. The study database 
will notify study personnel when a participant’s lab results are ready to be returned to the participant.  
 
Participants will receive APOL1 and/or PGx results via phone and/or in-person. Research Coordinators should 
call participants at the appropriate time (see Figure 1 and Tables 5-7), follow the ROR script (provided in the 
MOP), and end with a speak back in which participants will explain their results back in order to ensure 
comprehension. Research Coordinators should note the date, time, and completion status of all RORs in the 
study database. All participants will receive their genetic test results with lay explanations in writing and an 
educational booklet explaining their results and genetic risks via mail and/or secure email. Research Coordinators 
will offer all participants the option to speak by phone or in person with a study genetic counselor about their 
results. If a participant wants to speak with a genetic counselor, the Research Coordinator should contact the 
genetic counselor for their site on behalf of the patient, and the genetic counselor should reach out to the patient 
for counseling. 
 
Providers may be notified of participant results via standard site-specific laboratory return of results methods and, 
where possible, a CDS within the electronic health system as described in Section 7.8. The genetic testing results 
should also be stored in the participant’s medical records. 
7.7 
Data Collection from the Electronic Health Record 
Data from the local EHR will be used to determine: 1) components of the secondary endpoints (i.e., presence of 
CKD diagnosis codes in the 24 months prior to baseline and up to 8 months after baseline, urine tests obtained 
in the 24 months prior to baseline and in the 6 months after baseline), 2) events of interest (see Section 8.2), and 
3) variables needed for Other Planned Analyses including Cost Effectiveness Analysis (CEA) (see Section 9.6). 
Sites will extract the relevant EHR data using prespecified algorithms developed centrally by the IGNITE PTN 
CC or using site-developed algorithms. If using the CC-developed algorithms, sites will modify the algorithm 
codes based on their own customized EHR system. Sites will be asked to conduct EHR data downloads after at 
least 25% of the participants have completed their 6 month visit, and approximately 6-12 months after the last 
patient is randomized. EHR results will be sent to the IGNITE PTN CC via secure data transfer and formatted for 
data analyses. Details of the EHR download and transfer process will be provided separately to relevant site 
personnel. 

 
37 
 
7.8 
Clinical Decision Support System 
While participants will be notified of their APOL1 and PGx test results via a phone call and/or in-person, providers 
may be notified of participant results via standard site-specific laboratory return of results methods and, where 
possible, a CDS within the electronic health system. For APOL1 testing, sites should work with their institutional 
informational technology departments to set up provider CDS alerts for positive APOL1 results and for actionable 
PGx phenotypes when a relevant medication is ordered. APOL1 alerts should include the participant’s APOL1 
status, the risks associated with the participant’s APOL1 status, and treatment recommendations (including 
treatment for elevated BPs, ordering urine proteins tests, and ordering ACEs/ARBs), and additional educational 
materials delivered via the site-specific CDS implementation method. For PGx testing, provider alerts should 
indicate the participant’s genetic results, the predicted phenotype (i.e., efficacy of various hypertension 
medications), and treatment recommendations.  
 
Reflecting the pragmatic nature of the trial, the many involved research sites, and variations in local CDS policies, 
it is anticipated that there will be differences in CDS implementation details, but all sites will ensure that both 
participants and providers are alerted to APOL1 and PGx test results and associated significance. Details of the 
alerts will be provided separately to relevant site personnel. 
7.9 
Provider Surveys 
Providers that agree to participate in the baseline survey should be given a written baseline survey to complete 
or instructions for completing the baseline survey online.  
7.10 
Schedule of Activities 
Providers should be recruited and asked to complete the baseline survey as soon as possible after site activation. 
CDS alerts for providers should be activated as soon as lab results are entered into the electronic health record. 
 
Tables 5, 6, and 7 describe the participant schedule of events for GUARDD-US.  
 
 
 
 

 
38 
 
 
Table 5. Schedule of participant activities up to randomization for sites. 
Activities  
Prior to 
baseline 
  
Baseline visit 
Recruit participants 
X 
  
X  
Screen potential participants for interest/ 
eligibility 
X 
  
X 
Contact participant to schedule baseline visit 
X 
  
X  
Obtain consent 
X 
OR 
X 
Obtain BP & pulse & return BP results to 
participant 
  
  
X 
Distribute educational booklet/s to 
participant 
  
  
X 
Administer baseline participant survey 
  
  
X 
Perform sample collection 
  
  
X 
Randomize to APOL1 treatment at end of 
baseline visit & notify patients of their 
randomization assignment 
  
  
X 
 
 
 

 
39 
 
 
Table 6. Schedule of activities following participant baseline visit for sites participating in the PGx substudy. 
 
 
After Baseline 
& before 3M 
visit
3M visit
(+8 wks)
6M visit
(+8 wks)
After 6M 
visit
After Baseline 
& before 3M 
visit
3M visit
(+8 wks)
6M visit
(+8 wks)
After 6M 
visit
After Baseline 
& before 3M 
visit
3M visit
(+8 wks)
6M visit
(+8 wks)
After 6M 
visit
After Baseline 
& before 3M 
visit
3M visit
(+8 wks)
6M visit
(+8 wks)
After 6M 
visit
Participant surveys, BP & 
pulse measurements, & 
return of BP results to 
participant
X
X
X
X
X
X
X
X
APOL1 testing conducted at 
laboratory
X
X
X
X
Return APOL1 test results 
to participant verbally and 
with written explanation
X
X
X
X
Give educational booklet for 
APOL1 results via mail or 
secure email
X
X
X
X
PGx testing conducted at 
laboratory
X
X
X
X
Return PGx Results verbally 
and with written explanation
X
X
X
X
Give educational booklet for 
PGx results via mail or 
secure email
X
X
X
X
APOL1 Negative
PGx Control Group
APOL1 Negative
PGx Intervention Group
INTERVENTION GROUP
Activities
APOL1 Positive
CONTROL GROUP

 
40 
 
 
Table 7. Schedule of activities following participant baseline visit for sites participating not in the PGx substudy. 
 
  
After Baseline 
& before 3M 
visit
3M visit
(+8 wks)
6M visit
(+8 wks)
After 6M 
visit
After Baseline 
& before 3M 
visit
3M visit
(+8 wks)
6M visit
(+8 wks)
After 6M 
visit
Participant surveys, BP and 
pulse measurements, & 
return of BP results to 
participant
X
X
X
X
APOL1 testing conducted at 
laboratory
X
X
Return APOL1 test results 
to participant verbally and 
with written explanation
X
X
Give educational booklet for 
APOL1 results via mail or 
secure email
X
X
Activities
CONTROL GROUP
INTERVENTION GROUP

 
41 
 
8. 
SAFETY ASSESSMENT AND MONITORING 
 
GUARDD-US is an observational-type study that does not include a drug or device intervention. For this reason, 
no adverse events will be collected or recorded in the study database. Distress from return of results and events 
of interest will be monitored (as described in the next sections) and a Data and Safety Monitoring Board (DSMB) 
will provide trial oversight. Adverse events suspected to be related to study interventions should be reported to 
the reviewing IRB following local policies. Reportable events including unanticipated study related deaths will be 
collected in the study database per IRB reporting policies.  
8.1 
Distress from Return of Results 
Distress from return of results should be monitored at patient visits. If the participant seems overly distressed by 
the outcomes of the genetic test results, the Research Coordinator should: 
1. Offer the participant the opportunity to speak to the genetic counselor. If the genetic counselor is not 
immediately available, the Research Coordinator should help coordinate a phone call or meeting with the 
genetic counselor based on participant’s preference. 
2. Inform the Project Manager who should then: 
● Inform PIs 
● Document the event in the notes field of the participant’s study database record 
● Follow-up with participant  
8.2 
Events of Interest 
EHR data will be reviewed to monitor emergency department visits and hospitalizations. Sites will be asked to 
conduct two EHR data downloads, one after at least 25% of the participants have completed their 6 month visit, 
and another approximately 6-12 months after the last patient is randomized. EHR results will be sent to the 
IGNITE PTN CC via secure data transfer and formatted for data analyses. Details of the EHR download and 
transfer process will be provided separately to relevant site personnel. 
8.3 
Safety Monitoring/Data and Safety Monitoring Board 
The DSMB, appointed by the NHGRI, will be responsible for providing recommendations regarding the conduct 
of the study and guidance to ensure the safety and well-being of participants. The DSMB will meet semi-
annually with one conference call and one in-person/virtual meeting. A DSMB Charter will be developed 
detailing the procedures to be followed. A Data and Safety Monitoring Plan and a separate DSMB statistical 
analysis plan (SAP) will be developed in collaboration with the IGNITE PTN, IGNITE PTN CC, and NHGRI, and 
enacted by the DSMB. 
8.4 
Early Termination and Participant Discontinuation 
Early termination considerations will generally apply only to emerging issues of major concern, or problems with 
trial conduct that suggest the trial could not be completed successfully with a reliable conclusion in a feasible 
time frame. 
 
The site investigator, sponsor or institution may stop involvement of any participant in this research study at any 
time without their consent. This may be because the research study is being stopped, the instructions of the study 
team have not been followed, the investigator believes it is in the participant’s best interest, or for any other 
reason. If specimens or data have been stored as part of the research study, they too may be destroyed without 
participant consent. 
  

 
42 
 
9. 
STATISTICAL ANALYSIS PLAN AND SAMPLE SIZE 
9.1 
Sample Size Determination 
Main Study 
In GUARDD, there was a 13% prevalence of APOL1 positive individuals among hypertension participants and a 
standard deviation of 18.1 mm Hg for SBP. A separate unpublished pilot study from Indiana University showed a 
20% prevalence of APOL1 positive individuals among participants with CKD and an estimated CKD prevalence 
of 50%. Finally, another study showed a 26% prevalence of APOL1 positive AAs with CKD9. As such, the initial 
sample size determination assumed a 17% prevalence of APOL1 positive individuals. However, observation of 
the prevalence of the APOL1 positive study participants during the course of the study led investigators and the 
DSMB to believe that this assumption was too high and the actual prevalence in the study population was 
between 14 and 15 percent. Assuming a conservative14% prevalence of APOL1 positive individuals based on 
these studies, a sample size of approximately 6700 for the randomized population would result in approximately 
938 APOL1 positive individuals with at least 469 in each arm for the main study population examined here. Using 
a two tailed t-test and assuming an overall 5% level of significance, 10% lost-to-follow up, two interim analyses, 
and a standard deviation of 18.1 mm of Hg, a sample size of 6700 for the randomized population and 
approximately 938 for the APOL1 positive individuals will detect a 3.5 mm Hg difference in the change in SBP 
from baseline to 3 months between Intervention - APOL1 positive and Control - APOL1 positive groups with at 
least 80% power. This sample size determination assumes 10% of the 938 APOL1 positive individuals could drop 
out of the study before 3 months and therefore have incomplete data on SBP change from baseline to 3 months.  
APOL1 positive individuals with incomplete data on SBP change from baseline to 3 months cannot be included 
in the primary endpoint analysis.  Therefore, the final analysis on the primary endpoint needs at least 844 APOL1 
positive individuals who have complete data for SBP change from baseline to 3 months to detect a 3.5 mm Hg 
difference between two treatment groups. Enrollment will continue until the 844 target can be ensured.  Since 
APOL1 and SBP data could be missing for various reasons, approximately 50 additional participants will be 
randomized to help us to reach this 844 target. This makes the total randomization target to be approximately 
6750. Enrollment may end prior to the 6750 target if the study team is certain that the necessary 844 APOL1 
positive individuals with complete SBP change data can be achieved. 
 
 
 
PGx Substudy  
Of the approximately 6750 participants in the GUARDD-US study, approximately 4400 will also be at a site 
participating in the PGx substudy. A sample size of 4400 with a 14% prevalence of APOL1 positive individuals 
would result in 1892 participants for the PGx substudy (Intervention – APOL1 negative participants) with 946 
participants in the PGx Control and PGx Intervention arms. Using a two tailed t-test and assuming a 5% level of 
significance, 10% lost-to-follow up, and a standard deviation of 20 mm Hg (obtained from an unpublished study 
from the University of Florida), a sample size of 4400 for the randomized population and 1892 for the PGx 
substudy will detect a 3.1 mm Hg difference in the change in SBP from baseline to 3 months between the PGx 
Intervention group and PGx Control group with approximately 90% power.  
 
 

 
43 
 
 
9.2 
General Statistical Methods 
A detailed SAP will be developed and contained in a separate document. Prior to analysis, study population 
details including the number randomized, in each treatment arm, and lost to follow-up will be described. Baseline 
participant characteristics will be summarized as means, standard deviations, medians, and/or 25th, 75th 
percentiles for continuous variables, and as counts and percentages for categorical variables. Model assumptions 
will be examined prior to analysis and transformations implemented, if necessary, to more adequately meet the 
assumptions. Unless otherwise stated, hypotheses will be tested as two-sided with a significance level of 0.05. 
9.3 
Population for Analyses 
Population for Main Study Objectives 
Participants from the Randomized Population who test positive for APOL1. 
 
Population for PGx Substudy Objective 
Participants from the PGx substudy participating sites who are randomized to Intervention in the main study and 
test negative for APOL1 are included in the PGx substudy population. Only participants who have non-missing 
PGx test results are included in the population for the primary and secondary analyses.   
9.4 
Analysis of the Primary Endpoint 
To determine the effect of knowledge of a positive APOL1 status on SBP, we will compare the change in SBP 
from baseline to 3 months of the Intervention – APOL1 positive group to the change in SBP from baseline to 3 
months of the Control - APOL1 positive group using a two sided t-test with an overall two-sided type I error of 
0.05. Participants that are APOL1 negative in both the Intervention and Control groups will not be included. This 
primary analysis will be conducted according to the principle of intention-to-treat (ITT) with participants 
analyzed and endpoints attributed according to the treatment arm to which the participants were randomized, 
regardless of subsequent crossover or post-randomization medical care within the pre-specified subset of 
APOL1 positive participants.  
9.5 
Analysis of the Secondary Endpoints 
The effect of knowledge of a positive APOL1 status on secondary endpoints [i.e., change in urine 
microalbuminuria/proteinuria 
orders 
from 
baseline 
to 
6 
months 
(Y/N), 
documented 
order 
of 
microalbuminuria/proteinuria tests by 6 months (Y/N), change in documented diagnosis for stage 3 CKD and 
above (Y/N) from baseline to 6 months, documented diagnosis of CKD stage 3 and above by 6 months (Y/N), 
change in documented diagnosis for any stage CKD from baseline to 6 months (Y/N), and documented diagnosis 
of all stages of CKD by 6 months (Y/N) ] will be compared between Intervention - APOL1 positives and Control - 
APOL1 positives with the proportion difference test. 
9.6 
Other Planned Analyses 
Trends in SBP. In addition to the primary endpoint analysis described above, we will compare the time trends in 
SBP between Intervention – APOL1 positive individuals and Control – APOL1 positive individuals using a 
repeated measures mixed model. Since participants are randomized to Intervention and Control groups and not 
to the APOL1 positive subgroups within Intervention and Control groups, there could be important differences in 
baseline characteristics between the two groups. For this reason, we will conduct covariate-adjusted repeated 
measures mixed models that will account for differences in baseline characteristics that differ between the 
Intervention – APOL1 positive group and the Control – APOL1 positive group. Potential baseline covariates 
include baseline SBP, age, sex, and baseline CKD. We will select the appropriate covariance matrix (e.g., 

 
44 
 
compound symmetry, autoregressive, unstructured, or other covariance structure) based on the data to account 
for repeated measures. 
 
CKD subset. If the data provide evidence of an overall difference in the primary outcome (change in SBP from 
baseline to 3 months) between Intervention – APOL1 positive group and the Control – APOL1 positive groups, 
we will further examine whether the effect of knowledge of a positive APOL1 status on SBP differs among those 
with and without CKD. This subgroup analyses will involve testing for interactions between treatment arm and 
CKD using linear regression. Effect estimates will be carefully (conservatively) interpreted in conjunction with 
the formal interaction test. If the interaction is significant, we will test whether the time trends in effect of early 
versus delayed knowledge of a positive APOL1 status on SBP differs among Intervention – APOL1 positive 
group and the Control – APOL1 positive groups in those with CKD at baseline using a covariate-adjusted 
repeated measures mixed model. Potential covariates are the same as described above. We will select the 
appropriate covariance matrix (e.g., compound symmetry, autoregressive, unstructured, or other covariance 
structure) based on the data to account for repeated measures.  
 
Controlled versus Uncontrolled Blood Pressure Subset. We will also examine whether the effect of knowledge 
of a positive APOL1 status on SBP differs among those whose blood pressure is well-controlled at baseline 
versus those whose blood pressure is not well-controlled at baseline. This subgroup analyses will involve 
testing for interactions between treatment arm and whether or not SBP is 140 mm Hg or greater at baseline 
using linear regression. Effect estimates will be carefully (conservatively) interpreted in conjunction with the 
formal interaction test. As an additional subgroup analysis, we will similarly examine the effect of knowledge of 
a positive APOL1 status on SBP between those on treatment for hypertension versus those not on treatment in 
the subset of participants with SBP 140 mm Hg or greater. 
 
Cost-Effectiveness (CE). Complete details of the cost-effectiveness analysis (CEA) will be presented in a 
separate SAP depending on the outcome of the main study. Briefly, two analyses will be conducted comparing 
economic outcomes in Intervention – APOL1 positive and the Control – APOL1 positive groups. In the first, within-
trial cost analysis, 6-month total healthcare cost will be estimated per participant using estimates of intervention 
costs (obtained from Centers for Medicare and Medicaid Services (CMS) physician fee schedule17), medication 
costs (obtained from participant survey, EHR costs per cost center and/or total costs, VAFFS drug prices18, 
National Average Drug Acquisition Cost (NADAC) drug prices19, Medicare drug prices20), and downstream health 
care costs of inpatient, outpatient, and emergency department use (from participant survey, EHR costs per cost 
center and/or total costs, Medicare outpatient prospective payment system (PPS) for healthcare common 
procedure coding system (HCPCS)21, cost-to-charge-ratio (CCR) for estimating inpatient costs from charges22). 
The analyses will be adjusted for baseline 3-month total costs and utility scores by means of regression. The 
second, long-term CE analysis, will use a microsimulation model with five health states (Well, Cardiovascular 
Disease (CVD), ESRD, CVD plus ESRD, and Death) for predicting CE outcomes over a 5-year, 10-year and 
lifetime horizon following U.S. recommendations23. The microsimulation model’s predictions of CVD, ESRD and 
competing mortality rates will be informed by published epidemiological risk models and U.S. life tables. 
Specifically, we will use the Pooled Cohort Equations24 for modeling CVD and epidemiological studies for linking 
CKD stage to long-term ESRD risk with the following risk factors as input parameters: participant demographics 
(age, gender, and race) obtained from participant surveys; 6-month systolic blood pressure measurements; 6-
month smoking status and preventive medication use (BP med) obtained from participant surveys; and 6-month 
diabetes status, eGFR, urine albumin to creatinine ratio, and blood cholesterol parameters obtained from the 
EHR. The estimated event rates of CVD, ESRD and competing mortality will be modified using expected rate 
ratios of blood pressure lowering therapy estimated from difference in 6-month change of systolic blood pressure 
from baseline. Rate ratios will be based on published meta-analyses of trials on blood pressure lowering 
medication. The microsimulation model will be used to estimate cumulative costs and QALYs as a function of life 
expectancy and simulated CVD and ESRD events for each trial participant. Long-term utility and cost penalties 

 
45 
 
conditioned on increasing age, CVD, and ESRD will be based on the literature. Details of the procedures for 
obtaining EHR data and estimates from the EHR will be provided in the MOP and SAP. 
 
PGx Substudy. Analyses for the PGx substudy will compare outcomes between APOL1 negative individuals 
with immediate PGx ROR (PGx Intervention) and APOL1 negative individuals with delayed PGx ROR (PGx 
Control). A two sided t-test with a two-sided type I error of 0.05 will be used to evaluate differences in the 
change in SBP from baseline to the 3 month study visit between PGx Intervention and PGx Control groups. To 
evaluate time trends in SBP, we will also conduct covariate-adjusted repeated measures mixed models that will 
account for differences in baseline characteristics that differ between the PGx Intervention group and the PGx 
Control group. Potential baseline covariates are as described above. We will select the appropriate covariance 
matrix (e.g., compound symmetry, autoregressive, unstructured, or other covariance structure) based on the 
data to account for repeated measures. Additional exploratory endpoints and analyses for the PGx substudy 
will be described in a separate SAP. 
 
Details of these statistical analyses along with all other exploratory analyses (e.g., mediators, moderators and 
psychobehavioral impact of results disclosure on participant outcomes and provider treatment 
recommendations, and medication adherence) will be described in the study SAP.  
 
Long-Term Exploratory Outcomes: 
Research participants can consent for long-term follow up of kidney function. We will use appropriate 
procedures (including secure linkage, honest broker procedures, etc.) to access several databases, including 
patient electronic medical records, or restricted databases such as USRDS (United States Renal Data System) 
and CMS to track kidney function measurements, blood pressure, medication usage and health outcomes 
related to kidney disease up to 10 years from the date of enrollment, for patients who agree. We will then 
analyze these data as part of our exploratory outcomes and assess effect of interventions on long-term kidney 
outcomes. 
 
Impact of Social Determinants of Health: 
Data from participant surveys will be used to explore the impact of individual-level social determinants of health 
on primary, secondary, and exploratory study outcomes. Participant address will be used for linkage to publicly 
available data on community-level determinants of health (eg, Social CDC Vulnerability Index). 
9.7 
Interim Analyses 
  
A single planned interim analysis was planned initially for this study. To account for repeated significance testing 
of the accumulating data, the group sequential method of Lan and DeMets will be used as a guide for interpreting 
this interim analysis.  Monitoring boundaries for the primary endpoint will be based on a two-sided symmetric 
Lan-DeMets spending function using O’Brien-Fleming type boundaries with an overall two-sided significance 
level of α=0.05. The O’Brien-Fleming approach requires large critical values early in the study but relaxes (i.e., 
decreases) the critical value as the trial progresses. The primary and interim analyses will compare SBP at 3 
months among APOL1 positive individuals in the Control arm to APOL1 positive individuals in the Intervention 
arm. Because APOL1 genotype (i.e., positive vs. negative) for participants in the Control arm is determined 
around the time of the 6 month study visit, only participants that have completed their 6 month study visit will be 
included in the interim analysis. To account for the delays in receiving genetic testing results, the interim analysis 
will be targeted to occur when approximately 25% of the participants have completed their 6 month study visit. 
Using the O’Brien-Fleming type boundary at 25% information, if the analysis calculates a p-value that is less than 
0.00009, stopping the trial for efficacy or harm will be proposed. In order to maintain the overall significance level 
of 0.05, the final analysis of the primary endpoint will be considered significant for p-values less than 0.049975. 
 

 
46 
 
If the interim analysis does not propose stopping for efficacy (p-value <0.00009 and the intervention has the 
larger reduction in SBP at 3 months), then the conditional power to detect a significant result at the end of the 
trial will be estimated. The conditional power will be presented to the DSMB to facilitate discussion of whether 
the trial should be stopped for futility.  
 
An additional interim analysis was performed per request by the DSMB in May, 2022.  In order to maintain the 
overall significance level of 0.05 after this second interim analysis, the definition of significant p-value for the final 
analysis is recalculated by continuing to use the Lan-DeMets function with O’Brien-Fleming type boundaries 
appropriately for the approximate percent information at which the interim analysis occurred. Due to the 
occurrence of this second interim analysis, the final analysis of the primary endpoint will be considered significant 
if p-value is less than 0.0492.  
9.8 
Handling of Missing Data 
 
For the primary and secondary statistical analyses described above, multiple imputation will be used for all 
missing values except those due to participant death. To ensure that the missing at random assumption for 
multiple imputation is valid, we will compare baseline SBP and other patient characteristics in those lost to follow 
up to participants retained on their randomization assignment. We will also do sensitivity analyses where we 
compare results obtained with multiple imputation to those obtained without imputation. Missing values due to 
death will not be imputed and will therefore not be included in the analyses.  
 
For exploratory repeated measures analyses, missing data are easily handled in repeated measures mixed 
models, as long as the missing at random assumption is valid. However, the missing at random assumption 
cannot be tested.  Accordingly, for exploratory analyses using repeated measures mixed models, we will also 
conduct a sensitivity analysis where missing values are imputed using multiple imputation. The results with and 
without multiple imputation will be compared. More complete details of the handling of missing values under 
different circumstances will be described in the SAP. 
9.9 
Multiplicity 
With the primary and various secondary endpoints that have been outlined, there is a multiplicity of analyses to 
be performed, which leads to an increased probability that at least one of the comparisons could be "significant" 
by chance. Adjusting for the effects of the repeated significance testing for the multiplicity of secondary endpoints 
would require that very small significance levels be used for every comparison. Therefore, rather than adjusting 
for multiple comparisons, statistical results (e.g., p values) will only be presented for the primary endpoint 
analysis. We will be conservative in the interpretation of secondary analyses and report only point estimates and 
95% confidence intervals. We have also pre-specified the primary and secondary outcome variables to avoid 
over-interpretation of strictly exploratory comparisons.   

 
47 
 
10. 
DATA MANAGEMENT  
10.1 
Data Entry and Record Keeping 
GUARDD-US will have 4 main data sources: data collected from participants (survey, blood pressure and pulse) 
and providers (survey), genetic testing results from designated laboratories, data from the EHR, and publicly 
available data for CEA analyses. Data from patients and providers should be entered directly into study database 
by trained and qualified personnel at each clinical site. Site staff will receive training on the use of the study 
database. After staff are trained, they will receive a unique user identification and password to access data entry 
forms for their site. Access codes should not be shared and are non-transferable.  
 
Laboratories will transfer genetic testing results to the IGNITE PTN CC and follow standard site-specific return of 
results procedures for providers. The genotype and result (i.e., positive versus negative) for each participant will 
then be automatically imported to the participant’s study database record from laboratory produced output files. 
The accuracy of the automatic import of laboratory results will be verified by comparing the results recorded in 
the study database to an external record of the result for a subset of the study participants. 
 
Sites will extract the relevant data from their EHR (see Section 7.7) and transfer those data to the IGNITE PTN 
CC following procedures that will be specified. Briefly, sites will be given a list of information to extract for their 
GUARDD-US participants, a common format that data should be converted to, and procedures for secure file 
transfer to the CC. Transfers of data will occur after at least 25% of the participants have completed their 6 month 
visit and 6-12 months after the last participant is randomized. 
 
Data to be used for cost-effectiveness analyses (CEA) will be obtained via participant surveys administered at 
study visits, direct measurement at study visits (for blood pressure), via the EHR, and via publicly available data 
sources (CMS physician fee schedule17, VAFFS drug prices18, NADAC drug prices19, Medicare drug prices20, 
PPS for HCPCS21, and CCR for estimating inpatient costs from charges22). Publicly available data sources can 
be downloaded freely at the end of the study from corresponding online sources and stored on secure servers at 
the CC. Any specialized data collection procedures will be presented in the MOP. Details on the data to be used 
for CEA are presented in Section 9.6. 
10.2 
Data Element Definitions 
Baseline SBP will be defined as the mean of the 2nd and 3rd measurements taken according to the GUARDD-US 
Blood Pressure Protocol provided in the MOP.  Similarly, follow-up SBP will be the average of the 2nd and 3rd 
SBP measures at the follow-up visit, or alternatively the SBP from the EHR entered into the study database by 
the site in accordance with the study manual of procedures (MOP).   
 
Secondary Endpoints will be defined as follows: 
 
1. Change in urine microalbuminuria/proteinuria orders from baseline to 6 months (Y/N) 
a. Order of urine microalbuminuria/proteinuria test at baseline is a binary variable (Y/N) where ‘Y’ is 
defined as the presence of urine proteinuria or urine microalbuminuria diagnostic code (i.e. 
82043/84156 (Current Procedural Terminology (CPT) codes) OR the presence of urine 
microalbuminuria/proteinuria lab test order and/or result in the participant’s EHR record at any 
point in the 12 months prior to baseline. 
b. Order of urine microalbuminuria/proteinuria test at 6 months is a binary variable (Y/N) where ‘Y’ 
is defined as the presence of urine proteinuria or urine microalbuminuria diagnostic code 
82043/84156 (CPT codes) OR the presence of urine microalbuminuria/proteinuria lab test order 
and/or result in the participant’s EHR record at any point from baseline to 6 months. 

 
48 
 
c. Change in urine microalbuminuria/proteinuria orders is a binary variable (Y/N) where ‘Y’ is 
defined as no order of urine microalbuminuria/proteinuria test at baseline and having an order of 
urine microalbuminuria/proteinuria test at 6 months [No for 1a, Yes for 1b = NY]. 
 
2. Documented order of microalbuminuria/proteinuria tests by 6 months is a binary variable (Y/N) where ‘Y’ 
is defined as the change in urine microalbuminuria/proteinuria orders (as described in 1c) OR (order of 
urine microalbuminuria/proteinuria test at baseline) [NY, YN or YY] 
 
3. Change in documented diagnosis for stage 3 CKD and above from baseline to 6 months (Y/N) 
a. Documented diagnosis at baseline is a binary variable (Y/N) where ‘Y’ is defined as [the 
presence of a CKD ICD10 diagnosis codes of N18.3 – N18.5 in the 24 months prior to baseline]. 
b. Documented diagnosis at 6 months is a binary variable (Y/N) where ‘Y’ is defined as [the 
presence of a CKD ICD10 diagnosis codes of N18.3 – N18.6 in the 6 months after baseline]. 
c. Change in documented diagnosis for stage 3 CKD and above is a binary variable (Y/N) where ‘Y’ 
is defined as no documented diagnosis at baseline and documented diagnosis at 6 months [No 
for 3a, Yes for 3b = NY]. 
 
4. Documented diagnosis of stage 3 and above CKD by 6 months is a binary variable (Y/N) where ‘Y’ is 
defined as (change in documented diagnosis for stage 3 CKD (as described in 3c)) OR (documented 
diagnosis at baseline (as described in 3a)) [NY, YN or YY]. 
 
5. Change in documented diagnosis for any stage CKD from baseline to 6 months (Y/N) 
a. Documented diagnosis at baseline is a binary variable (Y/N) where ‘Y’ is defined as [the 
presence of a CKD ICD10 diagnosis code (i.e., N18.x; E08.22; E09.22; E10.22; E11.22; E13.22) 
in the 24 months prior to baseline]. 
b. Documented diagnosis at 6 months is a binary variable (Y/N) where ‘Y’ is defined as [the 
presence of a CKD ICD10 diagnosis code (i.e., E18.x; E08.22; E09.22; E10.22; E11.22; E13.22) 
in the 6 months after baseline]. 
c. Change in documented diagnosis for any stage CKD is a binary variable defined as no 
documented diagnosis at baseline and documented diagnosis at 6 months [No for 5a, Yes for 5b 
= NY]. 
 
6. Documented diagnosis of any stage CKD by 6 months is a binary variable (Y/N) where ‘Y’ is defined as 
(the change in documented diagnosis of any stage CKD (as described in 5c)) OR (documented 
diagnosis at baseline (as described in 5a)) [NY, YN or YY]. 
 
For CEA analyses, the following definitions for variables obtained from the EHR will be used: 
 
1. 6-month CKD stage will be defined with the follow categories using the most recent GFR measurement 
obtained between baseline and 6 months:  
a. Stage 1 with normal or high GFR (GFR > 90 mL/min) 
b. Stage 2 Mild CKD (GFR = 60-89 mL/min) 
c. Stage 3A Moderate CKD (GFR = 45-59 mL/min) 
d. Stage 3B Moderate CKD (GFR = 30-44 mL/min) 
e. Stage 4 Severe CKD (GFR = 15-29 mL/min) 
f. Stage 5 End Stage CKD (GFR <15 mL/min) 
2. 6-month blood cholesterol:  The last observed blood cholesterol level observed prior to baseline.  
Missing values will be imputed.  

 
49 
 
10.3 
Database Management and Quality Control of Data 
The IGNITE PTN CC will develop and manage the GUARDD-US study database and perform internal database 
quality-control checks. The CC will conduct data audits throughout the course of the trial. These audits are 
intended to identify data errors, protocol deviations, failure of standardization, missing data, or inconsistencies. 
Any out-of-range values and missing or inconsistent key variables are flagged and addressed/answered at the 
site in real time during the data entry process. 
 
All data will be transferred daily from the study database to SAS datasets and stored on the CC’s secure servers. 
The CC will periodically perform additional data quality checks in SAS. Clinical sites may also be given regular 
feedback directly to discuss issues identified by QC assessments.  
10.4 
Study Close Out 
The end of the trial is defined as the end of participant follow-up in the trial. Upon completion of the study, the 
IGNITE PTN CC and/or their designee will notify the site of closeout. The CC and/or their designee will ensure 
that the Investigator’s regulatory files are up to date and complete, and that any outstanding issues from previous 
correspondences have been resolved. Other issues to be reviewed at the closeout include: discussing retention 
of study files, possibility of site audits, publication policy, and notifying the IRB of study closure. 
 

 
50 
 
11. 
ETHICAL AND HUMAN SUBJECTS CONSIDERATIONS  
11.1 
Institutional Review Board/Ethics Committee Review 
This study will be initiated only after all required documentation has been reviewed and approved by the central 
IRB according to national and international regulations. The investigator will provide the IGNITE PTN CC or 
their designee with the study approval documentation before the study may begin. The same is applicable for 
the implementation of changes introduced by amendments. Where applicable, the investigator must also 
provide to the IGNITE PTN CC and/or their designee the following documentation:  
1. A copy of IRB annual re-approval of the protocol per current Title 21 CFR 312.66 regulations and 1997 
International Conference on Harmonization guidelines. 
2. IRB approval of revisions to the informed consent documents. Administrative changes (such as a change 
in address or phone number) must be sent to IRBs/Ethics Committees but do not require their approval.  
3. The investigator must submit periodic status reports to their Executive Committee as required, as well as 
notification of completion of the study and a final report where applicable.  
4. The investigator will provide the IGNITE PTN CC or their designee with documentation of all approvals.  
11.2 
Use and Disclosure of Protected Health Information  
For clinical trial sites located in the United States, an Authorization for the use and disclosure of PHI under the 
HIPAA Privacy Rule [45 CFR § 164.102 et seq] will be obtained from every trial participant prior to, or at the time 
of, enrollment. The investigator is responsible for obtaining participants’ authorizations and signatures, and for 
explaining the elements of the HIPAA Authorization form. HIPAA Authorization may either be a separate form or 
included in the study ICF, dependent upon local requirements. 
11.3 
Confidentiality and Privacy  
Participant confidentiality will be maintained throughout the clinical study in a way that ensures the information 
can always be tracked back to the source data. For this purpose, a unique participant identification code (ID 
number) will be used that allows identification of all data reported for each participant. Participant information 
collected in this study and all records will be kept confidential.  
 
Clinical data will be entered into an internet data entry system provided by the CC. The data system includes 
password protection and internal quality checks, such as automatic range checks to identify data that appear 
inconsistent, incomplete, or inaccurate. All data collection and storage devices will be password protected with 
a strong password and all sensitive research information on portable devices will be encrypted. Access to 
identifiable data will be limited to the study team. If it is necessary to use portable devices for initial collection of 
identifiers, the data files will be encrypted and the identifiers moved to a secure system as soon as possible.  
The portable device(s) will be locked in a secure location when it is not in use.  
 
11.4 
Publication and Data Sharing Policies  
 
The IGNITE PTN will have a Publications and Presentations Committee (PPC) with the primary responsibility for 
coordinating, monitoring, and reviewing all publications and presentations resulting from IGNITE PTN studies. In 
addition, the PPC will oversee the review, approval, and supervision of the secondary analyses and ancillary 
studies that are conducted within the Network. The goal of the PPC is to facilitate dissemination of the maximum 
amount of information from these studies in a scientifically sound and ethically responsible fashion in accordance 
with the unique nature of the IGNITE PTN mission. The IGNITE PTN CC will draft a PPC charter in collaboration 
with NHGRI, PPC, and the IGNITE PTN, which specifies the publication policies and procedures. 
 
The sharing of datasets will be performed following standard operating procedures (SOPs) at the IGNITE PTN 

 
51 
 
CC, requirements for NIH policy for data sharing, and guidelines for NIH Data Set Preparation. The de-identified 
or anonymized data and documentation in standardized formats may be made available in dbGaP, ClinVar or 
other NHGRI-approved cloud based platforms for sharing to the larger scientific community. Requested 
unrestricted data may be made available after database lock and after all planned primary and secondary 
analyses have been published to parties who sign a data sharing agreement, which stipulates that data must be: 
1) used solely for research purposes, 2) properly acknowledged in resulting publications, 3) kept confidential and 
inaccessible to third parties, and 4) destroyed or returned after analyses are completed. Additionally, users must 
agree not to use data to identify individual participants.  
 
 

 
52 
 
12. 
PROTOCOL DEVIATIONS 
 
A protocol deviation is defined as an event where the Investigator or site personnel did not conduct the study 
according to the protocol or the Investigator Agreement. Investigators are required to obtain prior approval from 
the IGNITE PTN CC and the reviewing IRB before initiating deviations from the protocol, except where necessary 
to protect the life or physical well-being of a participant in an emergency. Such approval will be documented and 
maintained in study files. Prior approval is generally not expected in situations where unforeseen circumstances 
are beyond the Investigator’s control, (e.g., participant did not attend scheduled follow-up visit, blood sample lost 
by laboratory, etc.); however, the event is still considered a deviation. Deviations will be reported to the IGNITE 
PTN CC and/or their designee regardless of whether medically justifiable, or taken to protect the participant in an 
emergency. Investigators will maintain documentation of the dates and reasons for each deviation from the 
protocol in compliance with the International Conference on Harmonisation Good Clinical Practice guidelines. 

 
53 
 
13. 
CONFLICT OF INTEREST 
 
Institutions and investigators must report all present or potential financial conflicts of interest to the NIH, including 
any financial conflicts of interest identified in accordance with the 2011 42 CRF Part 50 Subpart F in the time and 
manner specified in the regulation. In addition, the DSMB membership is restricted to individuals free of significant 
or apparent conflicts of interest. The source of these conflicts may be financial, scientific or regulatory in nature. 
The IGNITE PTN CC will hold and update annually conflict-of-interest statements from each member. Any 
member who develops a potential conflict of interest during the course of the trial should inform other members 
of the DSMB. If the potential conflict of interest is determined to be substantial and relevant, the member should 
resign from the DSMB. 
 
 

 
54 
 
14. 
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Judd, E. and D.A. Calhoun, Management of hypertension in CKD: beyond the guidelines. Adv Chronic 
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and W.H. Kao, APOL1 variants associate with increased risk of CKD among African Americans. J Am 
Soc Nephrol, 2013. 24(9): p. 1484-91. 
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Nadkarni, G.N., O. Gottesman, J.G. Linneman, H. Chase, R.L. Berg, S. Farouk, R. Nadukuru, V. Lotay, 
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23. 
Sanders, G.D., P.J. Neumann, A. Basu, D.W. Brock, D. Feeny, M. Krahn, K.M. Kuntz, D.O. Meltzer, D.K. 
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Goff, D.C., Jr., D.M. Lloyd-Jones, G. Bennett, S. Coady, R.B. D'Agostino, R. Gibbons, P. Greenland, D.T. 
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Bozkurt, R.G. Brindis, L.H. Curtis, D. DeMets, J.S. Hochman, R.J. Kovacs, E.M. Ohman, S.J. Pressler, 
F.W. Sellke, W.K. Shen, S.C. Smith, Jr., and G.F. Tomaselli, 2013 ACC/AHA guideline on the assessment 
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56 
 
15. 
APPENDICES  
15.1 
Appendix A. Diabetes Diagnosis Codes 
 
Table 8. ICD10 diagnosis codes and descriptions for diabetes 
ICD-10-CM DIABETES 
DIAGNOSIS CODES 
DESCRIPTIONS 
E08.00 
Diabetes mellitus due to underlying condition with hyperosmolarity without 
nonketotic hyperglycemic-hyperosmolar coma (NKHHC) 
E08.01 
Diabetes mellitus due to underlying condition with hyperosmolarity with 
coma 
E08.10 
Diabetes mellitus due to underlying condition with ketoacidosis without coma 
E08.11 
Diabetes mellitus due to underlying condition with ketoacidosis with coma 
E08.21 
Diabetes mellitus due to underlying condition with diabetic nephropathy 
E08.22 
Diabetes mellitus due to underlying condition with diabetic chronic kidney 
disease 
E08.29 
Diabetes mellitus due to underlying condition with other diabetic kidney 
complication 
E08.311 
Diabetes mellitus due to underlying condition with unspecified diabetic 
retinopathy with macular edema 
E08.3129 
Diabetes mellitus due to underlying condition with mild nonproliferative 
diabetic retinopathy with macular edema, unspecified eye 
E08.319 
Diabetes mellitus due to underlying condition with unspecified diabetic 
retinopathy without macular edema 
E08.3211 
Diabetes mellitus due to underlying condition with mild nonproliferative 
diabetic retinopathy with macular edema, right eye 
E08.3212 
Diabetes mellitus due to underlying condition with mild nonproliferative 
diabetic retinopathy with macular edema, left eye 
E08.3213 
Diabetes mellitus due to underlying condition with mild nonproliferative 
diabetic retinopathy with macular edema, bilateral 
E08.3291 
Diabetes mellitus due to underlying condition with mild nonproliferative 
diabetic retinopathy without macular edema, right eye 
E08.3292 
Diabetes mellitus due to underlying condition with mild nonproliferative 
diabetic retinopathy without macular edema, left eye 
E08.3293 
Diabetes mellitus due to underlying condition with mild nonproliferative 
diabetic retinopathy without macular edema, bilateral 
E08.3311 
Diabetes mellitus due to underlying condition with moderate nonproliferative 
diabetic retinopathy with macular edema, right eye 
E08.3312 
Diabetes mellitus due to underlying condition with moderate nonproliferative 
diabetic retinopathy with macular edema, left eye 

 
57 
 
E08.3313 
Diabetes mellitus due to underlying condition with moderate nonproliferative 
diabetic retinopathy with macular edema, bilateral 
E08.3319 
Diabetes mellitus due to underlying condition with moderate nonproliferative 
diabetic retinopathy with macular edema, unspecified eye 
E08.3391 
Diabetes mellitus due to underlying condition with moderate nonproliferative 
diabetic retinopathy without macular edema, right eye 
E08.3392 
Diabetes mellitus due to underlying condition with moderate nonproliferative 
diabetic retinopathy without macular edema, left eye 
E08.3393 
Diabetes mellitus due to underlying condition with moderate nonproliferative 
diabetic retinopathy without macular edema, bilateral 
E08.3399 
Diabetes mellitus due to underlying condition with moderate nonproliferative 
diabetic retinopathy without macular edema, unspecified eye 
E08.3411 
Diabetes mellitus due to underlying condition with severe nonproliferative 
diabetic retinopathy with macular edema, right eye 
E08.3412 
Diabetes mellitus due to underlying condition with severe nonproliferative 
diabetic retinopathy with macular edema, left eye 
E08.3413 
Diabetes mellitus due to underlying condition with severe nonproliferative 
diabetic retinopathy with macular edema, bilateral 
E08.3419 
Diabetes mellitus due to underlying condition with severe nonproliferative 
diabetic retinopathy with macular edema, unspecified eye 
E08.3491 
Diabetes mellitus due to underlying condition with severe nonproliferative 
diabetic retinopathy without macular edema, right eye 
E08.3492 
Diabetes mellitus due to underlying condition with severe nonproliferative 
diabetic retinopathy without macular edema, left eye 
E08.3493 
Diabetes mellitus due to underlying condition with severe nonproliferative 
diabetic retinopathy without macular edema, bilateral 
E08.3499 
Diabetes mellitus due to underlying condition with severe nonproliferative 
diabetic retinopathy without macular edema, unspecified eye 
E08.351 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with macular edema 
E08.3511 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with macular edema, right eye 
E08.3512 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with macular edema, left eye 
E08.3513 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with macular edema, bilateral 
E08.3519 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with macular edema, unspecified eye 
E08.352 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with traction retinal detachment involving the macula 
E08.3521 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with traction retinal detachment involving the macula, right eye 

 
58 
 
E08.3522 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with traction retinal detachment involving the macula, left eye 
E08.3523 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with traction retinal detachment involving the macula, bilateral 
E08.3529 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with traction retinal detachment involving the macula, 
unspecified eye 
E08.353 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with traction retinal detachment not involving the macula 
E08.3531 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with traction retinal detachment not involving the macula, right 
eye 
E08.3532 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with traction retinal detachment not involving the macula, left 
eye 
E08.3533 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with traction retinal detachment not involving the macula, 
bilateral 
E08.354 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with combined traction retinal detachment and rhegmatogenous 
retinal detachment 
E08.3541 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with combined traction retinal detachment and rhegmatogenous 
retinal detachment, right eye 
E08.3542 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with combined traction retinal detachment and rhegmatogenous 
retinal detachment, left eye 
E08.3543 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with combined traction retinal detachment and rhegmatogenous 
retinal detachment, bilateral 
E08.3549 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with combined traction retinal detachment and rhegmatogenous 
retinal detachment, unspecified eye 
E08.355 
Diabetes mellitus due to underlying condition with stable proliferative 
diabetic retinopathy 
E08.3551 
Diabetes mellitus due to underlying condition with stable proliferative 
diabetic retinopathy, right eye 
E08.3552 
Diabetes mellitus due to underlying condition with stable proliferative 
diabetic retinopathy, left eye 
E08.3553 
Diabetes mellitus due to underlying condition with stable proliferative 
diabetic retinopathy, bilateral 

 
59 
 
E08.3559 
Diabetes mellitus due to underlying condition with stable proliferative 
diabetic retinopathy, unspecified eye 
E08.359 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy without macular edema 
E08.3591 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy without macular edema, right eye 
E08.3592 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy without macular edema, left eye 
E08.3593 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy without macular edema, bilateral 
E08.3599 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy without macular edema, unspecified eye 
E08.36 
Diabetes mellitus due to underlying condition with diabetic cataract 
E08.37 
Diabetes mellitus due to underlying condition with diabetic macular edema, 
resolved following treatment 
E08.37X1 
Diabetes mellitus due to underlying condition with diabetic macular edema, 
resolved following treatment, right eye 
E08.37X2 
Diabetes mellitus due to underlying condition with diabetic macular edema, 
resolved following treatment, left eye 
E08.37X3 
Diabetes mellitus due to underlying condition with diabetic macular edema, 
resolved following treatment, bilateral 
E08.37X9 
Diabetes mellitus due to underlying condition with diabetic macular edema, 
resolved following treatment, unspecified 
E08.39 
Diabetes mellitus due to underlying condition with other diabetic ophthalmic 
complication 
E08.3939 
Diabetes mellitus due to underlying condition with proliferative diabetic 
retinopathy with traction retinal detachment not involving the macula, 
unspecified eye 
E08.40 
Diabetes mellitus due to underlying condition with diabetic neuropathy, 
unspecified 
E08.41 
Diabetes mellitus due to underlying condition with diabetic mononeuropathy 
E08.42 
Diabetes mellitus due to underlying condition with diabetic polyneuropathy 
E08.43 
Diabetes mellitus due to underlying condition with diabetic autonomic 
(poly)neuropathy 
E08.44 
Diabetes mellitus due to underlying condition with diabetic amyotrophy 
E08.49 
Diabetes mellitus due to underlying condition with other diabetic 
neurological complication 
E08.51 
Diabetes mellitus due to underlying condition with diabetic peripheral 
angiopathy without gangrene 
E08.52 
Diabetes mellitus due to underlying condition with diabetic peripheral 
angiopathy with gangrene 

 
60 
 
E08.59 
Diabetes mellitus due to underlying condition with other circulatory 
complications 
E08.610 
Diabetes mellitus due to underlying condition with diabetic arthropathy 
E08.618 
Diabetes mellitus due to underlying condition with other diabetic arthropathy 
E08.620 
Diabetes mellitus due to underlying condition with diabetic dermatitis 
E08.621 
Diabetes mellitus due to underlying condition with foot ulcer 
E08.622 
Diabetes mellitus due to underlying condition with other skin ulcer 
E08.628 
Diabetes mellitus due to underlying condition with other skin complications 
E08.630 
Diabetes mellitus due to underlying condition with periodontal disease 
E08.638 
Diabetes mellitus due to underlying condition with other oral complications 
E08.641 
Diabetes mellitus due to underlying condition with hypoglycemia with coma 
E08.649 
Diabetes mellitus due to underlying condition with hypoglycemia without 
coma 
E08.65 
Diabetes mellitus due to underlying condition with hyperglycemia 
E08.69 
Diabetes mellitus due to underlying condition with other specified 
complication 
E08.8 
Diabetes mellitus due to underlying condition with unspecified complication 
E08.9 
Diabetes mellitus due to underlying condition without complications 
E09.00 
Drug or chemical induced diabetes mellitus with hyperosmolarity without 
nonketotic hyperglycemic-hyperosmolar coma (NKHHC) 
E09.01 
Drug or chemical induced diabetes mellitus with hyperosmolarity with coma 
E09.10 
Drug or chemical induced diabetes mellitus with ketoacidosis without coma 
E09.11 
Drug or chemical induced diabetes mellitus with ketoacidosis with coma 
E09.21 
Drug or chemical induced diabetes mellitus with diabetic nephropathy 
E09.22 
Drug or chemical induced diabetes mellitus with diabetic chronic kidney 
disease 
E09.29 
Drug or chemical induced diabetes mellitus with other diabetic kidney 
complication 
E09.311 
Drug or chemical induced diabetes mellitus with unspecified diabetic 
retinopathy with macular edema 
E09.319 
Drug or chemical induced diabetes mellitus with unspecified diabetic 
retinopathy without macular edema 
E09.3211 
Drug or chemical induced diabetes mellitus with mild nonproliferative 
diabetic retinopathy with macular edema, right eye 
E09.3212 
Drug or chemical induced diabetes mellitus with mild nonproliferative 
diabetic retinopathy with macular edema, left eye 
E09.3213 
Drug or chemical induced diabetes mellitus with mild nonproliferative 
diabetic retinopathy with macular edema, bilateral 
E09.3219 
Drug or chemical induced diabetes mellitus with mild nonproliferative 
diabetic retinopathy with macular edema, unspecified eye 
E09.3291 
Drug or chemical induced diabetes mellitus with mild nonproliferative 
diabetic retinopathy without macular edema, right eye 

 
61 
 
E09.3292 
Drug or chemical induced diabetes mellitus with mild nonproliferative 
diabetic retinopathy without macular edema, left eye 
E09.3293 
Drug or chemical induced diabetes mellitus with mild nonproliferative 
diabetic retinopathy without macular edema, bilateral 
E09.3299 
Drug or chemical induced diabetes mellitus with mild nonproliferative 
diabetic retinopathy without macular edema, unspecified eye 
E09.3311 
Drug or chemical induced diabetes mellitus with moderate nonproliferative 
diabetic retinopathy with macular edema, right eye 
E09.3312 
Drug or chemical induced diabetes mellitus with moderate nonproliferative 
diabetic retinopathy with macular edema, left eye 
E09.3313 
Drug or chemical induced diabetes mellitus with moderate nonproliferative 
diabetic retinopathy with macular edema, bilateral 
E09.3319 
Drug or chemical induced diabetes mellitus with moderate nonproliferative 
diabetic retinopathy with macular edema, unspecified eye 
E09.3391 
Drug or chemical induced diabetes mellitus with moderate nonproliferative 
diabetic retinopathy without macular edema, right eye 
E09.3392 
Drug or chemical induced diabetes mellitus with moderate nonproliferative 
diabetic retinopathy without macular edema, left eye 
E09.3393 
Drug or chemical induced diabetes mellitus with moderate nonproliferative 
diabetic retinopathy without macular edema, bilateral 
E09.3399 
Drug or chemical induced diabetes mellitus with moderate nonproliferative 
diabetic retinopathy without macular edema, unspecified eye 
E09.3411 
Drug or chemical induced diabetes mellitus with severe nonproliferative 
diabetic retinopathy with macular edema, right eye 
E09.3412 
Drug or chemical induced diabetes mellitus with severe nonproliferative 
diabetic retinopathy with macular edema, left eye 
E09.3413 
Drug or chemical induced diabetes mellitus with severe nonproliferative 
diabetic retinopathy with macular edema, bilateral 
E09.3419 
Drug or chemical induced diabetes mellitus with severe nonproliferative 
diabetic retinopathy with macular edema, unspecified eye 
E09.3491 
Drug or chemical induced diabetes mellitus with severe nonproliferative 
diabetic retinopathy without macular edema, right eye 
E09.3492 
Drug or chemical induced diabetes mellitus with severe nonproliferative 
diabetic retinopathy without macular edema, left eye 
E09.3493 
Drug or chemical induced diabetes mellitus with severe nonproliferative 
diabetic retinopathy without macular edema, bilateral 
E09.3499 
Drug or chemical induced diabetes mellitus with severe nonproliferative 
diabetic retinopathy without macular edema, unspecified eye 
E09.3511 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with macular edema, right eye 
E09.3512 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with macular edema, left eye 

 
62 
 
E09.3513 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with macular edema, bilateral 
E09.3519 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with macular edema, unspecified eye 
E09.3521 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with traction retinal detachment involving the macula, right eye 
E09.3522 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with traction retinal detachment involving the macula, left eye 
E09.3523 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with traction retinal detachment involving the macula, bilateral 
E09.3529 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with traction retinal detachment involving the macula, 
unspecified eye 
E09.3531 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with traction retinal detachment not involving the macula, right 
eye 
E09.3532 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with traction retinal detachment not involving the macula, left 
eye 
E09.3533 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with traction retinal detachment not involving the macula, 
bilateral 
E09.3539 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with traction retinal detachment not involving the macula, 
unspecified eye 
E09.3541 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with combined traction retinal detachment and rhegmatogenous 
retinal detachment, right eye 
E09.3542 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with combined traction retinal detachment and rhegmatogenous 
retinal detachment, left eye 
E09.3543 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with combined traction retinal detachment and rhegmatogenous 
retinal detachment, bilateral 
E09.3549 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy with combined traction retinal detachment and rhegmatogenous 
retinal detachment, unspecified eye 
E09.3551 
Drug or chemical induced diabetes mellitus with stable proliferative diabetic 
retinopathy, right eye 
E09.3552 
Drug or chemical induced diabetes mellitus with stable proliferative diabetic 
retinopathy, left eye 

 
63 
 
E09.3553 
Drug or chemical induced diabetes mellitus with stable proliferative diabetic 
retinopathy, bilateral 
E09.3559 
Drug or chemical induced diabetes mellitus with stable proliferative diabetic 
retinopathy, unspecified eye 
E09.3591 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy without macular edema, right eye 
E09.3592 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy without macular edema, left eye 
E09.3593 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy without macular edema, bilateral 
E09.3599 
Drug or chemical induced diabetes mellitus with proliferative diabetic 
retinopathy without macular edema, unspecified eye 
E09.36 
Drug or chemical induced diabetes mellitus with diabetic cataract 
E09.37X1 
Drug or chemical induced diabetes mellitus with diabetic macular edema, 
resolved following treatment, right eye 
E09.37X2 
Drug or chemical induced diabetes mellitus with diabetic macular edema, 
resolved following treatment, left eye 
E09.37X3 
Drug or chemical induced diabetes mellitus with diabetic macular edema, 
resolved following treatment, bilateral 
E09.37X9 
Drug or chemical induced diabetes mellitus with diabetic macular edema, 
resolved following treatment, unspecified eye 
E09.39 
Drug or chemical induced diabetes mellitus with other diabetic ophthalmic 
complication 
E09.40 
Drug or chemical induced diabetes mellitus with neurological complications 
with diabetic neuropathy, unspecified 
E09.41 
Drug or chemical induced diabetes mellitus with neurological complications 
with diabetic mononeuropathy 
E09.42 
Drug or chemical induced diabetes mellitus with neurological complications 
with diabetic polyneuropathy 
E09.43 
Drug or chemical induced diabetes mellitus with neurological complications 
with diabetic autonomic (poly)neuropathy 
E09.44 
Drug or chemical induced diabetes mellitus with neurological complications 
with diabetic amyotrophy 
E09.49 
Drug or chemical induced diabetes mellitus with neurological complications 
with other diabetic neurologic complication 
E09.51 
Drug or chemical induced diabetes mellitus with diabetic peripheral 
angiopathy without gangrene 
E09.52 
Drug or chemical induced diabetes mellitus with diabetic peripheral 
angiopathy with gangrene 
E09.59 
Drug or chemical induced diabetes mellitus with other circulatory 
complications 

 
64 
 
E09.610 
Drug or chemical induced diabetes mellitus with diabetic neuropathic 
arthropathy 
E09.618 
Drug or chemical induced diabetes mellitus with other diabetic arthropathy 
E09.620 
Drug or chemical induced diabetes mellitus with diabetic dermatitis 
E09.621 
Drug or chemical induced diabetes mellitus with foot ulcer 
E09.622 
Drug or chemical induced diabetes mellitus with other skin ulcer 
E09.628 
Drug or chemical induced diabetes mellitus with other skin complications 
E09.630 
Drug or chemical induced diabetes mellitus with periodontal disease 
E09.638 
Drug or chemical induced diabetes mellitus with other oral complications 
E09.641 
Drug or chemical induced diabetes mellitus with hypoglycemia with coma 
E09.649 
Drug or chemical induced diabetes mellitus with hypoglycemia without coma 
E09.65 
Drug or chemical induced diabetes mellitus with hyperglycemia 
E09.69 
Drug or chemical induced diabetes mellitus with other specified complication 
E09.8 
Drug or chemical induced diabetes mellitus with unspecified complications 
E09.9 
Drug or chemical induced diabetes mellitus without complications 
E10.10 
Type 1 diabetes mellitus with ketoacidosis without coma 
E10.11 
Type 1 diabetes mellitus with ketoacidosis with coma 
E10.21 
Type 1 diabetes mellitus with diabetic nephropathy 
E10.22 
Type 1 diabetes mellitus with diabetic chronic kidney disease 
E10.29 
Type 1 diabetes mellitus with other diabetic kidney complication 
E10.311 
Type 1 diabetes mellitus with unspecified diabetic retinopathy with macular 
edema 
E10.319 
Type 1 diabetes mellitus with unspecified diabetic retinopathy without 
macular edema 
E10.3211 
Type 1 diabetes mellitus with mild nonproliferative diabetic retinopathy with 
macular edema, right eye 
E10.3212 
Type 1 diabetes mellitus with mild nonproliferative diabetic retinopathy with 
macular edema, left eye 
E10.3213 
Type 1 diabetes mellitus with mild nonproliferative diabetic retinopathy with 
macular edema, bilateral 
E10.3219 
Type 1 diabetes mellitus with mild nonproliferative diabetic retinopathy with 
macular edema, unspecified eye 
E10.3291 
Type 1 diabetes mellitus with mild nonproliferative diabetic retinopathy 
without macular edema, right eye 
E10.3292 
Type 1 diabetes mellitus with mild nonproliferative diabetic retinopathy 
without macular edema, left eye 
E10.3293 
Type 1 diabetes mellitus with mild nonproliferative diabetic retinopathy 
without macular edema, bilateral 
E10.3299 
Type 1 diabetes mellitus with mild nonproliferative diabetic retinopathy 
without macular edema, unspecified eye 
E10.3311 
Type 1 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
with macular edema, right eye 

 
65 
 
E10.3312 
Type 1 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
with macular edema, left eye 
E10.3313 
Type 1 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
with macular edema, bilateral 
E10.3319 
Type 1 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
with macular edema, unspecified eye 
E10.3391 
Type 1 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
without macular edema, right eye 
E10.3392 
Type 1 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
without macular edema, left eye 
E10.3393 
Type 1 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
without macular edema, bilateral  
E10.3399 
Type 1 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
without macular edema, unspecified eye 
E10.3411 
Type 1 diabetes mellitus with severe nonproliferative diabetic retinopathy 
with macular edema, right eye 
E10.3412 
Type 1 diabetes mellitus with severe nonproliferative diabetic retinopathy 
with macular edema, left eye 
E10.3413 
Type 1 diabetes mellitus with severe nonproliferative diabetic retinopathy 
with macular edema, bilateral 
E10.3419 
Type 1 diabetes mellitus with severe nonproliferative diabetic retinopathy 
with macular edema, unspecified eye 
E10.3491 
Type 1 diabetes mellitus with severe nonproliferative diabetic retinopathy 
without macular edema, right eye 
E10.3492 
Type 1 diabetes mellitus with severe nonproliferative diabetic retinopathy 
without macular edema, left eye 
E10.3493 
Type 1 diabetes mellitus with severe nonproliferative diabetic retinopathy 
without macular edema, bilateral 
E10.3499 
Type 1 diabetes mellitus with severe nonproliferative diabetic retinopathy 
without macular edema, unspecified eye 
E10.3511 
Type 1 diabetes mellitus with proliferative diabetic retinopathy with macular 
edema, right eye 
E10.3512 
Type 1 diabetes mellitus with proliferative diabetic retinopathy with macular 
edema, left eye 
E10.3513 
Type 1 diabetes mellitus with proliferative diabetic retinopathy with macular 
edema, bilateral 
E10.3519 
Type 1 diabetes mellitus with proliferative diabetic retinopathy with macular 
edema, unspecified eye 
E10.3521 
Type 1 diabetes mellitus with proliferative diabetic retinopathy with traction 
retinal detachment involving the macula, right eye 
E10.3522 
Type 1 diabetes mellitus with proliferative diabetic retinopathy with traction 
retinal detachment involving the macula, left eye 

 
66 
 
E10.3523 
Type 1 diabetes mellitus with proliferative diabetic retinopathy with traction 
retinal detachment involving the macula, bilateral 
E10.3529 
Type 1 diabetes mellitus with proliferative diabetic retinopathy with traction 
retinal detachment involving the macula, unspecified eye 
E10.3531 
Type 1 diabetes melliuts with proliferative diabetic retinopathy with traction 
rentinal detachment not involving the macula, right eye 
E10.3532 
Type 1 diabetes melliuts with proliferative diabetic retinopathy with traction 
rentinal detachment not involving the macula, left eye 
E10.3533 
Type 1 diabetes melliuts with proliferative diabetic retinopathy with traction 
rentinal detachment not involving the macula, bilateral 
E10.3539 
Type 1 diabetes melliuts with proliferative diabetic retinopathy with traction 
rentinal detachment not involving the macula, unspecified eye 
E10.3541 
Type 1 diabetes mellitus with proliferative diabetic retinopathy with 
combined traction retinal detachment and rhegmatogenous retinal 
detachment, right eye 
E10.3542 
Type 1 diabetes mellitus with proliferative diabetic retinopathy with 
combined traction retinal detachment and rhegmatogenous retinal 
detachment, left eye 
E10.3543 
Type 1 diabetes mellitus with proliferative diabetic retinopathy with 
combined traction retinal detachment and rhegmatogenous retinal 
detachment, bilateral 
E10.3549 
Type 1 diabetes mellitus with proliferative diabetic retinopathy with 
combined traction retinal detachment and rhegmatogenous retinal 
detachment, unspecified eye 
E10.3551 
Type 1 diabetes mellitus with stable proliferative diabetic retinopathy, right 
eye 
E10.3552 
Type 1 diabetes mellitus with stable proliferative diabetic retinopathy, left 
eye 
E10.3553 
Type 1 diabetes mellitus with stable proliferative diabetic retinopathy, 
bilateral 
E10.3559 
Type 1 diabetes mellitus with stable proliferative diabetic retinopathy, 
unspecified eye 
E10.3591 
Type 1 diabetes mellitus with proliferative diabetic retinopathy without 
macular edema, right eye 
E10.3592 
Type 1 diabetes mellitus with proliferative diabetic retinopathy without 
macular edema, left eye 
E10.3593 
Type 1 diabetes mellitus with proliferative diabetic retinopathy without 
macular edema, bilateral 
E10.3599 
Type 1 diabetes mellitus with proliferative diabetic retinopathy without 
macular edema, unspecified eye 
E10.36 
Type 1 diabetes mellitus with diabetic cataract 

 
67 
 
E10.37X1 
Type 1 diabetes mellitus with diabetic macular edema, resolved following 
treatment, right eye 
E10.37X2 
Type 1 diabetes mellitus with diabetic macular edema, resolved following 
treatment, left eye 
E10.37X3 
Type 1 diabetes mellitus with diabetic macular edema, resolved following 
treatment, bilateral 
E10.37X9 
Type 1 diabetes mellitus with diabetic macular edema, resolved following 
treatment, unspecified eye 
E10.39 
Type 1 diabetes mellitus with other diabetic ophthalmic complication 
E10.40 
Type 1 diabetes mellitus with diabetic neuropathy, unspecified 
E10.41 
Type 1 diabetes mellitus with diabetic mononeuropathy 
E10.42 
Type 1 diabetes mellitus with diabetic polyneuropathy 
E10.43 
Type 1 diabetes mellitus with diabetic autonomic (poly)neuropathy 
E10.44 
Type 1 diabetes mellitus with diabetic amyotrophy 
E10.49 
Type 1 diabetes mellitus with other diabetic neurological complication 
E10.51 
Type 1 diabetes mellitus with diabetic peripheral angiopathy without 
gangrene 
E10.52 
Type 1 diabetes mellitus with diabetic peripheral angiopathy with gangrene 
E10.59 
Type 1 diabetes mellitus with other circulatory complications 
E10.610 
Type 1 diabetes mellitus with diabetic neuropathic arthropathy 
E10.618 
Type 1 diabetes mellitus with other diabetic arthropathy 
E10.620 
Type 1 diabetes mellitus with diabetic dermatitis 
E10.621 
Type 1 diabetes mellitus with foot ulcer 
E10.622 
Type 1 diabetes mellitus with other skin ulcer 
E10.628 
Type 1 diabetes mellitus with other skin complications 
E10.630 
Type 1 diabetes mellitus with periodontal disease 
E10.638 
Type 1 diabetes mellitus with other oral complications 
E10.641 
Type 1 diabetes mellitus with hypoglycemia with coma 
E10.649 
Type 1 diabetes mellitus with hypoglycemia without coma 
E10.65 
Type 1 diabetes mellitus with hyperglycemia  
E10.69 
Type 1 diabetes mellitus with other specified complication 
E10.8 
Type 1 diabetes mellitus with unspecified complications 
E10.9 
Type 1 diabetes mellitus without complications 
E11.00 
Type 2 diabetes mellitus with hyperosmolarity without nonketotic 
hyperglycemic-hyperosmolar coma (NKHHC) 
E11.01 
Type 2 diabetes mellitus with hyperosmolarity with coma 
E11.10 
Type 2 diabetes mellitus with ketoacidosis without coma 
E11.11 
Type 2 diabetes mellitus with ketoacidosis with coma 
E11.21 
Type 2 diabetes mellitus with diabetic nephropathy 
E11.22 
Type 2 diabetes mellitus with diabetic chronic kidney disease 
E11.29 
Type 2 diabetes mellitus with other diabetic kidney complication 

 
68 
 
E11.311 
Type 2 diabetes mellitus with unspecified diabetic retinopathy with macular 
edema 
E11.319 
Type 2 diabetes mellitus with unspecified diabetic retinopathy without 
macular edema 
E11.3211 
Type 2 diabetes mellitus with mild nonproliferative diabetic retinopathy with 
macular edema, right eye 
E11.3212 
Type 2 diabetes mellitus with mild nonproliferative diabetic retinopathy with 
macular edema, left eye 
E11.3213 
Type 2 diabetes mellitus with mild nonproliferative diabetic retinopathy with 
macular edema, bilateral 
E11.3219 
Type 2 diabetes mellitus with mild nonproliferative diabetic retinopathy with 
macular edema, unspecified eye 
E11.3291 
 Type 2 diabetes mellitus with mild nonproliferative diabetic retinopathy 
without macular edema, right eye 
E11.3292 
 Type 2 diabetes mellitus with mild nonproliferative diabetic retinopathy 
without macular edema, left eye 
E11.3293 
 Type 2 diabetes mellitus with mild nonproliferative diabetic retinopathy 
without macular edema, bilateral 
E11.3299 
 Type 2 diabetes mellitus with mild nonproliferative diabetic retinopathy 
without macular edema, unspecified eye 
E11.3311 
Type 2 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
with macular edema, right eye 
E11.3312 
Type 2 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
with macular edema, left eye 
E11.3313 
Type 2 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
with macular edema, bilateral 
E11.3319 
Type 2 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
with macular edema, unspecified eye 
E11.3391 
Type 2 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
without macular edema, right eye 
E11.3392 
Type 2 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
without macular edema, left eye 
E11.3393 
Type 2 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
without macular edema, bilateral 
E11.3399 
Type 2 diabetes mellitus with moderate nonproliferative diabetic retinopathy 
without macular edema, unspecified eye 
E11.3411 
Type 2 diabetes mellitus with severe nonproliferative diabetic retinopathy 
with macular edema, right eye 
E11.3412 
Type 2 diabetes mellitus with severe nonproliferative diabetic retinopathy 
with macular edema, left eye 
E11.3413 
Type 2 diabetes mellitus with severe nonproliferative diabetic retinopathy 
with macular edema, bilateral 

 
69 
 
E11.3419 
Type 2 diabetes mellitus with severe nonproliferative diabetic retinopathy 
with macular edema, unspecified eye 
E11.3491 
Type 2 diabetes mellitus with severe nonproliferative diabetic retinopathy 
without macular edema, right eye 
E11.3492 
Type 2 diabetes mellitus with severe nonproliferative diabetic retinopathy 
without macular edema, left eye 
E11.3493 
Type 2 diabetes mellitus with severe nonproliferative diabetic retinopathy 
without macular edema, bilateral 
E11.3499 
Type 2 diabetes mellitus with severe nonproliferative diabetic retinopathy 
without macular edema, unspecified eye 
E11.3511 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with macular 
edema, right eye 
E11.3512 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with macular 
edema, left eye 
E11.3513 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with macular 
edema, bilateral 
E11.3519 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with macular 
edema, unspecified eye 
E11.3521 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with traction 
retinal detachment involving the macula, right eye 
E11.3522 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with traction 
retinal detachment involving the macula, left eye 
E11.3523 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with traction 
retinal detachment involving the macula, bilateral 
E11.3529 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with traction 
retinal detachment involving the macula, unspecified eye 
E11.3531 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with traction 
retinal detachment not involving the macula, right eye 
E11.3532 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with traction 
retinal detachment not involving the macula, left eye 
E11.3533 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with traction 
retinal detachment not involving the macula, bilateral 
E11.3539 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with traction 
retinal detachment not involving the macula, unspecified eye 
E11.3541 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with 
combined traction retinal detachment and rhegmatogenous retinal 
detachment, right eye 
E11.3542 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with 
combined traction retinal detachment and rhegmatogenous retinal 
detachment, left eye 

 
70 
 
E11.3543 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with 
combined traction retinal detachment and rhegmatogenous retinal 
detachment, bilateral 
E11.3549 
Type 2 diabetes mellitus with proliferative diabetic retinopathy with 
combined traction retinal detachment and rhegmatogenous retinal 
detachment, unspecified eye 
E11.3551 
Type 2 diabetes mellitus with stable proliferative diabetic retinopathy, right 
eye 
E11.3552 
Type 2 diabetes mellitus with stable proliferative diabetic retinopathy, left 
eye 
E11.3553 
Type 2 diabetes mellitus with stable proliferative diabetic retinopathy, 
bilateral 
E11.3559 
Type 2 diabetes mellitus with stable proliferative diabetic retinopathy, 
unspecified eye 
E11.3591 
Type 2 diabetes mellitus with proliferative diabetic retinopathy without 
macular edema, right eye 
E11.3592 
Type 2 diabetes mellitus with proliferative diabetic retinopathy without 
macular edema, left eye 
E11.3593 
Type 2 diabetes mellitus with proliferative diabetic retinopathy without 
macular edema, bilateral 
E11.3599 
Type 2 diabetes mellitus with proliferative diabetic retinopathy without 
macular edema, unspecified eye 
E11.36 
Type 2 diabetes mellitus with diabetic cataract 
E11.37X1 
Type 2 diabetes mellitus with diabetic macular edema, resolved following 
treatment, right eye 
E11.37X2 
Type 2 diabetes mellitus with diabetic macular edema, resolved following 
treatment, left eye 
E11.37X3 
Type 2 diabetes mellitus with diabetic macular edema, resolved following 
treatment, bilateral 
E11.37X9 
Type 2 diabetes mellitus with diabetic macular edema, resolved following 
treatment, unspecified eye 
E11.39 
Type 2 diabetes mellitus with other diabetic ophthalmic complication  
E11.40 
Type 2 diabetes mellitus with diabetic neuropathy, unspecified 
E11.41 
Type 2 diabetes mellitus with diabetic mononeuropathy 
E11.42 
Type 2 diabetes mellitus with diabetic polyneuropathy 
E11.43 
Type 2 diabetes mellitus with diabetic autonomic (poly)neuropathy   
E11.44 
Type 2 diabetes mellitus with diabetic amyotrophy 
E11.49 
Type 2 diabetes mellitus with other diabetic neurological complication 
E11.51 
Type 2 diabetes mellitus with diabetic peripheral angiopathy without 
gangrene 
E11.52 
Type 2 diabetes mellitus with diabetic peripheral angiopathy with gangrene 
E11.59 
Type 2 diabetes mellitus with other circulatory complications 

 
71 
 
E11.610 
Type 2 diabetes mellitus with diabetic neuropathic arthropathy 
E11.618 
Type 2 diabetes mellitus with other diabetic arthropathy 
E11.620 
Type 2 diabetes mellitus with diabetic dermatitis 
E11.621 
Type 2 diabetes mellitus with foot ulcer 
E11.622 
Type 2 diabetes mellitus with other skin ulcer 
E11.628 
Type 2 diabetes mellitus with other skin complications 
E11.630 
Type 2 diabetes mellitus with periodontal disease 
E11.638 
Type 2 diabetes mellitus with other oral complications 
E11.641 
Type 2 diabetes mellitus with hypoglycemia with coma 
E11.649 
Type 2 diabetes mellitus with hypoglycemia without coma 
E11.65 
Type 2 diabetes mellitus with hyperglycemia 
E11.69 
Type 2 diabetes mellitus with other specified complication 
E11.8 
Type 2 diabetes mellitus with unspecified complications 
E11.9 
Type 2 diabetes mellitus without complications 
E13.00 
Other specified diabetes mellitus with hyperosmolarity without nonketotic 
hyperglycemic-hyperosmolar coma (NKHHC) 
E13.01 
Other specified diabetes mellitus with hyperosmolarity with coma 
E13.10 
Other specified diabetes mellitus with ketoacidosis without coma 
E13.11 
Other specified diabetes mellitus with ketoacidosis with coma 
E13.21 
Other specified diabetes mellitus with diabetic nephropathy 
E13.22 
Other specified diabetes mellitus with diabetic chronic kidney disease 
E13.29 
Other specified diabetes mellitus with other diabetic kidney complication 
E13.311 
Other specified diabetes mellitus with unspecified diabetic retinopathy with 
macular edema 
E13.319 
Other specified diabetes mellitus with unspecified diabetic retinopathy 
without macular edema 
E13.3211 
Other specified diabetes mellitus with mild nonproliferative diabetic 
retinopathy with macular edema, right eye 
E13.3212 
Other specified diabetes mellitus with mild nonproliferative diabetic 
retinopathy with macular edema, left eye 
E13.3213 
Other specified diabetes mellitus with mild nonproliferative diabetic 
retinopathy with macular edema, bilateral 
E13.3219 
Other specified diabetes mellitus with mild nonproliferative diabetic 
retinopathy with macular edema, unspecified eye 
E13.3291 
Other specified diabetes mellitus with mild nonproliferative diabetic 
retinopathy without macular edema, right eye 
E13.3292 
Other specified diabetes mellitus with mild nonproliferative diabetic 
retinopathy without macular edema, left eye 
E13.3293 
Other specified diabetes mellitus with mild nonproliferative diabetic 
retinopathy without macular edema, bilateral 
E13.3299 
Other specified diabetes mellitus with mild nonproliferative diabetic 
retinopathy without macular edema, unspecified eye 

 
72 
 
E13.3311 
Other specified diabetes mellitus with moderate nonproliferative diabetic 
retinopathy with macular edema, right eye 
E13.3312 
Other specified diabetes mellitus with moderate nonproliferative diabetic 
retinopathy with macular edema, left eye 
E13.3313 
Other specified diabetes mellitus with moderate nonproliferative diabetic 
retinopathy with macular edema, bilateral 
E13.3319 
Other specified diabetes mellitus with moderate nonproliferative diabetic 
retinopathy with macular edema, unspecified eye 
E13.3391 
Other specified diabetes mellitus with moderate nonproliferative diabetic 
retinopathy without macular edema, right eye 
E13.3392 
Other specified diabetes mellitus with moderate nonproliferative diabetic 
retinopathy without macular edema, left eye 
E13.3393 
Other specified diabetes mellitus with moderate nonproliferative diabetic 
retinopathy without macular edema, bilateral 
E13.3399 
Other specified diabetes mellitus with moderate nonproliferative diabetic 
retinopathy without macular edema, unspecified eye 
E13.3411 
Other specified diabetes mellitus with severe nonproliferative diabetic 
retinopathy with macular edema, right eye 
E13.3412 
Other specified diabetes mellitus with severe nonproliferative diabetic 
retinopathy with macular edema, left eye 
E13.3413 
Other specified diabetes mellitus with severe nonproliferative diabetic 
retinopathy with macular edema, bilateral 
E13.3419 
Other specified diabetes mellitus with severe nonproliferative diabetic 
retinopathy with macular edema, unspecified eye 
E13.3491 
Other specified diabetes mellitus with severe nonproliferative diabetic 
retinopathy without macular edema, right eye 
E13.3492 
Other specified diabetes mellitus with severe nonproliferative diabetic 
retinopathy without macular edema, left eye 
E13.3493 
Other specified diabetes mellitus with severe nonproliferative diabetic 
retinopathy without macular edema, bilateral 
E13.3499 
Other specified diabetes mellitus with severe nonproliferative diabetic 
retinopathy without macular edema, unspecified eye 
E13.3511 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
macular edema, right eye 
E13.3512 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
macular edema, left eye 
E13.3513 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
macular edema, bilateral 
E13.3519 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
macular edema, unspecified eye 
E13.3521 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
traction retinal detachment involving the macula, right eye 

 
73 
 
E13.3522 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
traction retinal detachment involving the macula, left eye 
E13.3523 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
traction retinal detachment involving the macula, bilateral 
E13.3529 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
traction retinal detachment involving the macula, unspecified eye 
E13.3531 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
traction retinal detachment not involving the macula, right eye 
E13.3532 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
traction retinal detachment not involving the macula, left eye 
E13.3533 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
traction retinal detachment not involving the macula, bilateral 
E13.3539 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
traction retinal detachment not involving the macula, unspecified eye 
E13.3541 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
combined traction retinal detachment and rhegmatogenous retinal 
detachment, right eye 
E13.3542 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
combined traction retinal detachment and rhegmatogenous retinal 
detachment, left eye 
E13.3543 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
combined traction retinal detachment and rhegmatogenous retinal 
detachment, bilateral 
E13.3549 
Other specified diabetes mellitus with proliferative diabetic retinopathy with 
combined traction retinal detachment and rhegmatogenous retinal 
detachment, unspecified eye 
E13.3551 
Other specified diabetes mellitus with stable proliferative diabetic 
retinopathy, right eye 
E13.3552 
Other specified diabetes mellitus with stable proliferative diabetic 
retinopathy, left eye 
E13.3553 
Other specified diabetes mellitus with stable proliferative diabetic 
retinopathy, bilateral 
E13.3559 
Other specified diabetes mellitus with stable proliferative diabetic 
retinopathy, unspecified eye 
E13.3591 
Other specified diabetes mellitus with proliferative diabetic retinopathy 
without macular edema, right eye 
E13.3592 
Other specified diabetes mellitus with proliferative diabetic retinopathy 
without macular edema, left eye 
E13.3593 
Other specified diabetes mellitus with proliferative diabetic retinopathy 
without macular edema, bilateral 
E13.3599 
Other specified diabetes mellitus with proliferative diabetic retinopathy 
without macular edema, unspecified eye 

 
74 
 
E13.36 
Other specified diabetes mellitus with diabetic cataract 
E13.37X1 
Other specified diabetes mellitus with diabetic macular edema, resolved 
following treatment, right eye 
E13.37X2 
Other specified diabetes mellitus with diabetic macular edema, resolved 
following treatment, left eye 
E13.37X3 
Other specified diabetes mellitus with diabetic macular edema, resolved 
following treatment, bilateral 
E13.37X9 
Other specified diabetes mellitus with diabetic macular edema, resolved 
following treatment, unspecified eye 
E13.39 
Other specified diabetes mellitus with other diabetic ophthalmic complication  
E13.40 
Other specified diabetes mellitus with diabetic neuropathy, unspecified 
E13.41 
Other specified diabetes mellitus with diabetic mononeuropathy 
E13.42 
Other specified diabetes mellitus with diabetic polyneuropathy 
E13.43 
Other specified diabetes mellitus with diabetic autonomic (poly)neuropathy 
E13.44 
Other specified diabetes mellitus with diabetic amyotrophy 
E13.49 
Other specified diabetes mellitus with other diabetic neurological 
complication 
E13.51 
Other specified diabetes mellitus with diabetic peripheral angiopathy without 
gangrene 
E13.52 
Other specified diabetes mellitus with diabetic peripheral angiopathy with 
gangrene 
E13.59 
Other specified diabetes mellitus with other circulatory complications 
E13.610 
Other specified diabetes mellitus with diabetic neuropathic arthropathy 
E13.618 
Other specified diabetes mellitus with other diabetic arthropathy 
E13.620 
Other specified diabetes mellitus with diabetic dermatitis 
E13.621 
Other specified diabetes mellitus with foot ulcer 
E13.622 
Other specified diabetes mellitus with other skin ulcer 
E13.628 
Other specified diabetes mellitus with other skin complications 
E13.630 
Other specified diabetes mellitus with periodontal disease 
E13.638 
Other specified diabetes mellitus with other oral complications 
E13.641 
Other specified diabetes mellitus with hypoglycemia with coma 
E13.649 
Other specified diabetes mellitus with hypoglycemia without coma 
E13.65 
Other specified diabetes mellitus with hyperglycemia 
E13.69 
Other specified diabetes mellitus with other specified complication 
E13.8 
Other specified diabetes mellitus with unspecified complications 
E13.9 
Other specified diabetes mellitus without complications 
E8.3299 
Diabetes mellitus due to underlying condition with mild nonproliferative 
diabetic retinopathy without macular edema, unspecified eye 
O24.410 
Gestational diabetes mellitus in pregnancy, diet controlled 
O24.414 
Gestational diabetes mellitus in pregnancy, insulin controlled 

 
75 
 
O24.415 
Gestational diabetes mellitus in pregnancy controlled by oral hypoglycemic 
drugs 
O24.419 
Gestational diabetes mellitus in pregnancy unspecified control 
O24.420 
Gestational diabetes mellitus in childbirth, diet controlled 
O24.424 
Gestational diabetes mellitus in childbirth, insulin controlled 
O24.425 
Gestational diabetes mellitus in childbirth, controlled by oral hypoglycemic 
drugs 
O24.429 
Gestational diabetes mellitus in childbirth, unspecified control 
O24.430 
Gestational diabetes mellitus in the puerperium, diet controlled 
O24.434 
Gestational diabetes mellitus in the puerperium, insulin controlled 
O24.435 
Gestational diabetes mellitus in the puerperium, controlled by oral 
hypoglycemic drugs 
O24.439 
Gestational diabetes mellitus in the puerperium, unspecified control 
 
15.2 
 
 
 

 
76 
 
15.2  
Appendix B. PGx Substudy Gene Description and Evidence  
 
Overview: The PGx sub-study will examine the efficacy of providing genetic information for two gene-drug 
pairs. The first gene-drug pair is YEATS4 and thiazide diuretic efficacy, impacting first-line 
antihypertensive therapy in African Americans. The second gene-drug pair is NAT2 and hydralazine. 
Hydralazine is not first line therapy, but is used in the treatment of resistant hypertension. GUARDD-US 
will include patients with both hypertension and resistant hypertension. Neither gene-drug pair is presently 
recommended by CPIC, but both have significant evidence supporting their relationship in populations 
that include individuals of African ancestry. Given that 83% of the GUARDD-US intervention arm will be 
APOL1 negative, the inclusion of a HTN PGx sub-study is an economical means of testing a second 
hypothesis. 
Most individuals with hypertension require 2 or more agents to control blood pressure and those with 
resistant hypertension may require 4 or 5 agents. In contrast to other current PGx recommendations (e.g. 
antidepressants or opioids), antihypertensive agents are often not used in isolation. Thus, 
recommendations need to convey both dosing suggestions and/or relative efficacy to enable a provider 
to efficiently craft a regimen with fewer agents. This is of even greater importance in individuals with 
resistant hypertension. 
  
YEATS4: 
Evidence: The first gene-drug pair is YEATS4, predictive of thiazide efficacy in two independent cohorts. 
This gene-drug pair was associated with efficacy of thiazide diuretics (HCTZ) in the GERA and PEAR 
cohorts. It was discovered in a genome wide association of African American GERA patients (ST Turner) 
and later replicated in the PEAR cohort (JD Duarte). The SNP, rs7297610, is an expression quantitative 
locus of YEATS4, as expression is associated with both genotype and thiazide therapy. Citations are 
provided below. Although both GERA and PEAR studied HCTZ, we have decided to relay 
recommendations as a class effect (including both HCTZ and chlorthalidone). The rationale for this 
decision include the following: 1) the mechanisms of action are the same, 2) GUARDD-US is a pragmatic 
trial and the inclusion of the class effect enhances future generalizability, and 3) GUARDD-US includes 
individuals with CKD in whom chlorthalidone will be preferentially used by practitioners. We recognize 
hydrochlorothiazide (6-15 hours) and chlorthalidone (45-60 hours) each have a very different half-life. 
Overall, we feel the advantages of studying both drugs outweigh the potential heterogeneity. Further, we 
also note that the YEATS4 SNP is an expression quantitative loci and is anticipated to have a greater 
pharmacodynamic effect than pharmacokinetic effect. 
Effect size: The effect size of rs7297610 is large. The T allele confers reduced efficacy to thiazide 
diuretics, reducing change in SBP by 3.4 mmHg and change in DBP by 2.5 mmHg. Stated another way, 
individuals with a TC or TT genotype are expected to have a 9.6 mmHg reduction in SBP in response to 
HCTZ initiation. Individuals with a CC genotype are expected to have a 13.1 mmHg reduction in SBP in 
response to HCTZ initiation. 
Frequency: The minor allele frequency is ideal for testing effect size. The minor allele frequency of the T 
allele is ~0.3 with a dominant model for reduced efficacy. This means that approximately ½ of individuals 
(9% TT and 42% CT) would be expected to have reduced efficacy and ½ of individuals (49% CC) would 

 
77 
 
be expected to have increased/standard efficacy. Thus, ~1 in 2 individuals would have an actionable 
genotype. 
Recommendation: First line antihypertensive therapy for African Americans presently consists of either a 
calcium channel blocker or thiazide diuretic. Our recommendation focusses on selection of first line 
therapy. The PEAR study included HCTZ and atenolol. Beta-blockers are no longer first line 
antihypertensive therapy. Thus, although HCTZ was not directly compared to a CCB in the study, we still 
have evidence that the T allele reduces thiazide efficacy. Thus, we are recommending thiazide or CCB 
use as the first drug in those with a CC genotype, but only a CCB as first-line in those with a T allele. This 
recommendation is pragmatic and straightforward for clinicians. The GUARDD-US trial will help us to test 
the efficacy of this recommendation.  
Our recommendation does not include specific dosing recommendations for thiazide diuretics, only 
relative efficacy recommendations. The rationale for this decision is that there is limited dynamic range of 
thiazide efficacy (essentially 12.5 mg or 25 mg dosing) and in practice, many clinicians will begin therapy 
at 25 mg daily. The GERA trial included only one dose, 25 mg. The PEAR trial included a titration protocol, 
so the observed effect is a mix of the 12.5 mg and 25 mg dose. Thus, there is insufficient data to conclude 
a dose-effect relationship. 
  
Goal (Drug Class) 
Gene 
Genotype 
Recommendation 
First Line Therapy 
(Thiazide diuretic) 
YEATS4 
C/C 
This individual is predicted to have standard thiazide
efficacy. Consider use of a thiazide diuretic or calcium
channel blocker as first line treatment of hypertension. 
First Line Therapy 
(Thiazide diuretic) 
YEATS4 
TT or TC 
This individual is predicted to have reduced thiazide
efficacy. Consider use of an alternate first line therapy such
as a calcium channel blocker for treatment of hypertension. 
Resistant Hypertension 
(Hydralazine) 
NAT2 
*4/*X 
This individuals is predicted to have reduced hydralazine
efficacy and may require a higher starting dose or an
alternate agent such as clonidine, spironolactone, or
doxazosin for resistant hypertension. 
Resistant Hypertension 
(Hydralazine) 
NAT2 
2 
non-*4 
alleles 
This individual is predicted to have increased efficacy of
hydralazine. 
NAT2 Evidence: 
Evidence: The second gene-drug pair selected was NAT2 and hydralazine. Hydralazine is metabolized 
by NAT2, so poor metabolizers have increased circulating concentrations of hydralazine. In this situation, 
poor metabolizers and slow acetylators terms are synonymous. This relationship was first reported nearly 

 
78 
 
50 years ago. PharmGKB presently lists hydralzine-NAT2 as a level 3 recommendation, but there is only 
1 reference cited in PharmGKB. There is actually a preponderance of evidence (21 references) supporting 
the relationship between: 1) metabolizer status to hydralazine PK or blood pressure effect, 2) Metabolizer 
status to genotype, or 3) genotype directly to blood pressure effect. We also identified 3 negative studies, 
but in each there were limitations (underpowered or included multiple drugs which confounded the effect). 
Please see the references below. In summary, the level of evidence for this drug-gene pair could 
potentially support a future CPIC recommendation. NAT2 metabolism is also listed in the FDA drug label 
for hydralazine. The evidence includes data in African ancestry populations and the strongest effect is 
seen in slow acetylators/poor metabolizers. Based on evidence, it is possible that there is an intermediate 
phenotype, but the evidence is insufficient to distinguish blood pressure effects in rapid and intermediate 
acetylators. 
Effect size: The effect size of the acetylator phenotype is large. Poor metabolizers may require a dose 
adjustment of 40% to >100% based on metabolizer status. There is a wide dose prescribing range for 
hydralazine from 10 mg BID to 100 mg TID. 
Frequency: The allele frequency is ideal for testing effect size. In the African American population, 35% 
are intermediate (1 non-*4 allele) and ~50% are slow acetylators (possessing 2 non-*4 alleles). Thus, ~1 
in 2 individuals would have an actionable genotype. 
Recommendation: Based on the multitude of studies, we are relaying a climinical implication that poor 
metabolizers may have higher circulating concentrations with increased efficacy or risk for adverse 
effects. Normal/rapid metabolizers may require a higher dose of hydralazine or an alternate agent as 
compared to poor metabolizers (slow acetylators) to achieve equivalent blood pressure control. 
  
Thiazide and YEATS4 evidence 
1.       Shahin MH, Johnson JA. Mechanisms and pharmacogenetic signals underlying thiazide diuretics 
blood pressure response. Curr Opin Pharmacol. 2016 Apr;27:31-7. PMID: 26874237 
2.       Duarte JD, Turner ST, Tran B, Chapman AB, Bailey KR, Gong Y, Gums JG, Langaee TY, 
Beitelshees AL, Cooper-Dehoff RM, Boerwinkle E, Johnson JA. Association of chromosome 12 locus with 

 
79 
 
antihypertensive response to hydrochlorothiazide may involve differential YEATS4 expression. 
Pharmacogenomics J. 2013 Jun;13(3):257-63. Feb 21. PMID: 22350108 
3.       Turner ST, Bailey KR, Fridley BL, Chapman AB, Schwartz GL, Chai HS, Sicotte H, Kocher JP, 
Rodin AS, Boerwinkle E. Genomic association analysis suggests chromosome 12 locus influencing 
antihypertensive response to thiazide diuretic. Hypertension. 2008 Aug;52(2):359-65. PMID: 18591461 
  
Hydralazine and NAT2 evidence 
Evidence supporting the relationship of the NAT2 metabolic phenotype to hydralazine efficacy or PK 
1.    
Jounela AJ, Pasanen M, Mattila MJ. Acetylator phenotype and the antihypertensive response to 
hydralazine. Acta Med Scand. 1975 Apr;197(4):303-6. PMID: 1136859. 40% increased hydralazine dose 
needed in fast acetylators for same BP effect. 
2.       Timbrell JA, Harland SJ, Facchini V. Polymorphic acetylation of hydralazine. Clin Pharmacol Ther. 
1980 Sep;28(3):350-5. PMID: 7408395. Acetylation status relates to hydralazine metabolism. 
3.       Timbrell JA, Harland SJ. Identification and quantitation of hydrazine in the urine of patients treated 
with hydralazine. Clin Pharmacol Ther. 1979 Jul;26(1):81-8. PMID: 445966 
4.       Facchini V, Timbrell JA. Further evidence for an acetylator phenotype difference in the metabolism 
of hydralazine in man. Br J Clin Pharmacol. 1981 Apr;11(4):345-51. PMID: 7259927 
5.       Timbrell JA, Harland SJ, Facchini V. Effect of dose on acetylator phenotype distribution of 
hydralazine. Clin Pharmacol Ther. 1981 Mar;29(3):337-43. PMID: 7471604 
6.       Rashid JR1, Kofi-Tsepko, Juma FD. Acetylation status using hydralazine in African hypertensives 
at Kenyatta National Hospital. East Afr Med J. 1992 Jul;69(7):406-8. PMID: 1396201. Acetylation 
phenotype in African patients determines urinary MTP/hydralazine appearance. 
7.       Shepherd AM, Ludden TM, McNay JL, Lin MS. Hydralazine kinetics after single and repeated oral 
doses. Clin Pharmacol Ther. 1980 Dec;28(6):804-11. PMID: 7438695 
8.    
Graves DA1, Muir KT, Richards W, Steiger BW, Chang I, Patel B. Hydralazine dose-response 
curve analysis. J Pharmacokinet Biopharm. 1990 Aug;18(4):279-91. PMID: 2231320 
9.    
Rowell NP1, Clark K. The effects of oral hydralazine on blood pressure, cardiac output and 
peripheral resistance with respect to dose, age and acetylator status. Radiother Oncol. 1990 
Aug;18(4):293-8. PMID: 2244017. 
10.   Ramsay LE, Silas JH, Ollerenshaw JD, Tucker GT, Phillips FC, Freestone S. Should the acetylator 
phenotype be determined when prescribing hydralazine for hypertension? Eur J Clin Pharmacol. 
1984;26(1):39-42. 
11.   Shepherd A, Lin MS, McNay J, Ludden T, Musgrave G. Determinants of response to intravenous 
hydralazine in hypertension. Clin Pharmacol Ther. 1981 Dec;30(6):773-81. 
12.   Shepherd AM, McNay JL, Ludden TM, Lin MS, Musgrave GE. Plasma concentration and acetylator 
phenotype determine response to oral hydralazine. Hypertension. 1981 Sep-Oct;3(5):580-5. 
13.   Kalowski S1, Hua AS, Whitworth JA, Kincaid-Smith P. Hydrallazine with beta-blocker and diuretic in 
the treatment of hypertension. A double-blind crossover study. Med J Aust. 1979 Oct 20;2(8):439-40. 
14.   Zacest R, Koch-Weser J. Relation of hydralazine plasma concentration to dosage and hypotensive 
action. Clin Pharmacol Ther. 1972 May-Jun;13(3):420-5. 

 
80 
 
  
 
Evidence supporting the relationship of NAT2 metabolic phenotype and genotype (could include other drugs as 
well) 
1.       Al-Ahmad MM1, Amir N1, Dhanasekaran S1, John A2, Abdulrazzaq YM3, Ali BR2, Bastaki S1. 
Studies on N-Acetyltransferase (NAT2) Genotype Relationships in Emiratis: Confirmation of the Existence 
of Phenotype Variation among Slow Acetylators. Ann Hum Genet. 2017 Sep;81(5):190-196. PMID: 
28653770 
2.       Hein DW1, Doll MA. Accuracy of various human NAT2 SNP genotyping panels to infer rapid, 
intermediate and slow acetylator phenotypes. Pharmacogenomics. 2012 Jan;13(1):31-41. doi: 
10.2217/pgs.11.122. Epub 2011 Nov 17. PMID: 22092036 
3.       Suarez-Kurtz G, Vargens DD, Sortica VA, Hutz MH. Accuracy of NAT2 SNP genotyping panels to 
infer acetylator phenotypes in African, Asian, Amerindian and admixed populations. Pharmacogenomics 
13(8), 851–854 (2012). PMID: 22676187 
4.       Aklillu E1, Carrillo JA2, Makonnen E3, Bertilsson L4, Djordjevic N5. N-Acetyltransferase-2 (NAT2) 
phenotype is influenced by genotype-environment interaction in Ethiopians. Eur J Clin Pharmacol. 2018 
Jul;74(7):903-911 PMID: 29589062 
5.       Others 
6.       Patin E1, Barreiro LB, Sabeti PC, Austerlitz F, Luca F, Sajantila A, Behar DM, Semino O, 
Sakuntabhai A, Guiso N, Gicquel B, McElreavey K, Harding RM, Heyer E, Quintana-Murci L.  Deciphering 
the ancient and complex evolutionary history of human arylamine N-acetyltransferase genes.  Am J Hum 
Genet. 2006 Mar;78(3):423-36. Epub 2006 Jan 13. PMID: 16416399 
 
Evidence supporting the relationship of genotype to antihypertensive efficacy of hydralazine or metabolism.  
1.       Spinasse LB1, Santos AR, Suffys PN, Muxfeldt ES, Salles GF. PMID: 24444407. 
Pharmacogenomics. 2014 Feb;15(2):169-78.  Different phenotypes of the NAT2 gene influences 
hydralazine antihypertensive response in patients with resistant hypertension. PMID: 24444407 Clinical 
Trial in Brazilian population assessing HTN response by NAT2 genotype 
2.    
Garcés-Eisele SJ1, Cedillo-Carvallo B, Reyes-Núñez V, Estrada-Marín L, Vázquez-Pérez R, 
Juárez-Calderón M, Guzmán-García MO, Dueñas-González A, Ruiz-Argüelles A. Genetic selection of 
volunteers and concomitant dose adjustment leads to comparable hydralazine/valproate exposure. J Clin 

 
81 
 
Pharm Ther. 2014 Aug;39(4):368-75. PMID: 24702251. Mexican PK study showing >100% dose increase 
required for same AUC. 
3.    
Allen CE N-Acetyltransferase 2 Genotype-Dependent N-Acetylation of Hydralazine in Human 
Hepatocytes. Drug Metab Dispos. 2017 Dec;45(12):1276-1281. PMID: 29018032 
  
Other evidence/Gene summary: 
1.    
McDonagh EM, Boukouvala S, Aklillu E, Hein DW, Altman RB, Klein TE. PharmGKB summary: 
very important pharmacogene information for N-acetyltransferase 2. Pharmacogenet Genomics. 2014 
Aug;24(8):409-25. PMID: 24892773 
2.       BIDIL (hydralazine hydrochloride and isosorbide dinitrate) tablet, film coated. Arbor 
Pharmaceuticals, 
Inc; 
[Accessed 
26th 
March 
2013. 
.]. 
Drug 
label 
available 
from.http://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=e1e63cd5-d1e4-4af5-bad5-1ad41ea46b00.  
3. 
 
 
 
 
 
 
Hydralazine 
FDA 
drug 
label, 
https://www.accessdata.fda.gov/drugsatfda_docs/label/1996/008303s068lbl.pdf 
4.    
Gonzalez-Fierro A, Vasquez-Bahena D, Taja-Chayeb L, Vidal S, Trejo-Becerril C, Pérez-
Cardenas E, de la Cruz-Hernández E, Chávez-Blanco A, Gutiérrez O, Rodriguez D, Fernandez Z, 
Duenas-González A. Pharmacokinetics of hydralazine, an antihypertensive and DNA-demethylating 
agent, using controlled-release formulations designed for use in dosing schedules based on the acetylator 
phenotype. Int J Clin Pharmacol Ther. 2011 Aug; 49(8):519-24. 
5.    
Candelaria M, Gallardo-Rincón D, Arce C, Cetina L, Aguilar-Ponce JL, Arrieta O, González-Fierro 
A, Chávez-Blanco A, de la Cruz-Hernández E, Camargo MF, Trejo-Becerril C, Pérez-Cárdenas E, Pérez-
Plasencia C, Taja-Chayeb L, Wegman-Ostrosky T, Revilla-Vazquez A, Dueñas-González A. A phase II 
study of epigenetic therapy with hydralazine and magnesium valproate to overcome chemotherapy 
resistance in refractory solid tumors. Ann Oncol. 2007 Sep; 18(9):1529-38. 
  
Negative studies of Hydralazine: 
6.       M J Vandenburg, P Wright, J Holmes, H J Rogers, and R A Ahmad. The hypotensive response to 
hydralazine, in triple therapy, is not related to acetylator phenotype. Br J Clin Pharmacol. 1982 May; 13(5): 
747–750. 
7.       Hunyor SN. Hydrallazine and beta-blockade in refractory hypertension with characterization of 
acetylator phenotype. Aust N Z J Med. 1975 Dec;5(6):530-6. 
8.       Ludden TM, Shepherd AM, McNay JL Jr, Lin MS. Effect of intravenous dose on hydralazine kinetics 
after administration. Clin Pharmacol Ther. 1983 Aug;34(2):148-52.