Continuous Glucose Monitoring Initiation at Hospital Discharge: A Feasibility Pilot Study
Phase: NA
Conditions: Type 1 Diabetes, Type2 Diabetes, Hyperglycemia, Hypoglycemia, Hypoglycemia Unawareness
Sponsor: Washington University School of Medicine

 
 
 
 
 
 
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Continuous Glucose Monitoring Initiation at Hospital Discharge:  A 
Feasibility Pilot Sutdy 
 
 
Principal Investigator:  Paulina Cruz Bravo, MD 
 
 
 
 
 
 
 
Version Date/Number:  February 2, 2022/2 
 
 

 
 
 
 
 
 
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TABLE OF CONTENTS 
 
A 
INTRODUCTION & BACKGROUND .............................................................................................. 3 
B 
STUDY OBJECTIVES ......................................................................................................................... 3 
B1 
PRIMARY AIM ................................................................................................................................. 3 
B2 
SECONDARY AIMS ........................................................................................................................... 4 
C 
STUDY DESIGN ................................................................................................................................... 4 
C1 
OVERVIEW OR DESIGN SUMMARY .................................................................................................. 4 
C2 
SUBJECT SELECTION AND WITHDRAWAL ........................................................................................ 4 
2.a 
Inclusion Criteria ....................................................................................................................... 4 
1. 
18 years of age or older .................................................................................................................. 4 
2. 
Have diabetes (type 1 diabetes mellitus, type 2 diabetes mellitus, cystic fibrosis related diabetes 
mellitus) ................................................................................................................................................... 4 
3. 
Hemoglobin A1c greater than of equal to 8.0% or history of hypoglycemia unawareness ........... 4 
4. 
Able and willing to sign informed consent form ............................................................................. 4 
5. 
Have a valid telephone number ...................................................................................................... 4 
6. 
Willing to purchase FreeStyle Libre 2 CGM sensors out of pocket after discharge from hospital 4 
2.b.  
Exclusion Criteria ...................................................................................................................... 4 
2.c    Subject Recruitment Plans and Consent Process ........................................................................... 5 
2.d.    Risks and Benefits .......................................................................................................................... 5 
2.e.    Early Withdrawal of Subjects ........................................................................................................ 5 
C3 
STUDY DEVICE ................................................................................................................................ 6 
3.a 
Description ................................................................................................................................. 6 
D 
STUDY PROCEDURES ....................................................................................................................... 6 
D1 
SCREENING FOR ELIGIBILITY ........................................................................................................... 6 
D2 
SCHEDULE OF MEASUREMENTS ...................................................................................................... 6 
D3 
VISIT 1A: DURING HOSPITAL STAY ................................................................................................. 6 
STUDY TEAM MEMBER WILL MEET WITH PARTICIPANT, REVIEW INFORMED CONSENT FORM AND OBTAIN 
WRITTEN CONSENT.  STUDY TEAM MEMBER WILL OBTAIN THE FOLLOWING INFORMATION FROM PATIENT 
OR MEDICAL RECORD AFTER CONSENT IS OBTAINED: ................................................................................... 6 
D4 
VISIT 1B:  DAY OF HOSPITAL DISCHARGE: ...................................................................................... 7 
ON THE DAY OF PARTICIPANT’S DISCHARGE FROM THE HOSPITAL, ONE OF THE DIABETES EDUCATORS WILL 
COMPLETE THE FOLLOWING WITH THE PARTICIPANT: ................................................................................... 7 
D5 
FOLLOW UP TELEPHONE CALLS ...................................................................................................... 7 
E 
SAFETY MONITORING ..................................................................................................................... 9 
E1  Safety and Compliance Monitoring .................................................................................................. 9 
E2  Medical Monitoring .......................................................................................................................... 9 
F STATISTICAL PLAN ............................................................................................................................... 9 
F1 SAMPLE SIZE DETERMINATION AND POWER ........................................................................................... 9 
F2 STATISTICAL METHODS ........................................................................................................................... 9 
G  REFERENCES ........................................................................................................................................ 10 
 

 
 
 
 
 
 
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A Introduction & Background 
 
Diabetes is a very common comorbidity in hospitalized patients. Patients with 
diabetes are highly likely to be hospitalized, with insulin use increasing this 
likelihood (1). It is estimated that up to 38% of patients in the hospital have 
diabetes or hyperglycemia, and likely many more have pre diabetes (2). Diabetes 
is associated with worse hospital outcomes including increased risk for falls, 
infections and readmissions. The hospital stay represents an opportunity to 
intervene and optimize diabetes management. Patients at our hospital also have 
access to specialized services including endocrinologists and certified diabetes 
educators. However, diabetes is a complex disease and is common for patients 
to feel overwhelmed with the burden of therapy. Continuous glucose monitors 
(GCMs) are commercially FDA approved devices for single-patient use that can 
measure interstitial glucose every 5 minutes. They vary slightly in the number of 
wear days, display and need of calibrations. Studies have shown that CGM use 
improves diabetes control and decrease episodes of hypoglycemia (3-5). One 
barrier for the effectiveness is uptake, they are not prescribed enough by primary 
care providers, another significant barrier has been cost.  The overall goal of this 
current study is to assess the feasibility of initiating CGM in patients with diabetes 
at discharge. This strategy has the potential to overcome delay in accessing the 
technology and control cost.  
 
One study looked at the feasibility of use in older patients with diabetes and 
dementia in the outpatient setting. In this study, of 17 people consented and 12 
completed the study. Patient and caregivers reported that the device was 
nonintrusive and responded positively about recommending the device (6). 
Another study in the outpatient setting found that a total of 22 participants 
(48.9%) completed the study using the minimum number of 3 FreeStyle Libre 
sensors with  11 of the participants requiring extra sensors due to a faulty or 
misplaced sensor (7). One study using a 4 month Telehealth outpatient model 
utilizing CGM, showed 92% (55/60) completed the 4-month intervention, and 
78.2% (43/55) met the criteria of follow-up CGM sensor–wear periods >90 days 
from baseline. This study showed improved time in range and a decrease in A1C 
by 1.6% (8). 
 
B Study Objectives 
B1 Primary Aim 
To determine the feasibility of initiating a continuous glucose monitoring in 
patients with diabetes at hospital discharge.  We hypothesize that starting 
and continuing to use a CGM at this critical time is feasible.  Feasibility is 
defined as at least 20% of patients with diabetes referred for diabetes 
education meet inclusion criteria to participate and 75% agree to 

 
 
 
 
 
 
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participate.  From those who participate, at least 50% continue using the 
CGM at 3 months. 
B2 Secondary Aims 
1. To characterize the barriers to continuing CGM use after discharge.  We 
will systematically characterize the reasons for discontinuations (issues 
with wearing device, use, costs, getting refills, etc.) 
 
2. To assess the effect of CGM initiation at hospital discharge on diabetes 
outcomes:  Time in range, health utilization (clinic visits, ED visits, 
hospitalization), self-efficacy. 
 
C Study Design  
 
C1 Overview or Design Summary 
This study will be an interventional, single-arm, open-label, prospective 
design. 
C2 Subject Selection and Withdrawal  
One hundred eligible adult patients will be recruited to the study. 
2.a 
Inclusion Criteria 
1. 18 years of age or older 
2. Have diabetes (type 1 diabetes mellitus, type 2 diabetes mellitus, 
cystic fibrosis related diabetes mellitus) 
3. Hemoglobin A1c greater than or equal to 8.0% or history of 
hypoglycemia unawareness 
4. Able and willing to sign informed consent form 
5. Have a valid telephone number 
6. Willing to purchase FreeStyle Libre 2 CGM sensors out of pocket after 
discharge from hospital  
 
2.b.  Exclusion Criteria  
1. Unable to sign informed consent form 
2. Have altered mental status 
3. Unable to manage diabetes independently at home 
4. Have utilized CGM in the past 
5. Pregnancy 
6. New steroid-induced hyperglycemia 
7. Unwilling to participate in the study 
8. Have kidney disease requiring hemodialysis 
9. Taking high doses of vitamin C daily (greater than 500 mg every day) 

 
 
 
 
 
 
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2.c    Subject Recruitment Plans and Consent Process 
The study team will identify potential participants from patients referred to the 
diabetes service or diabetes education service.  Once a participant is identified, 
one of the study team members will approach the patient in their private hospital 
room, review the study and provide them with a written informed consent form to 
review.  The study team will follow up 1-2 days later or prior to discharge to 
determine if the patient is interested in participating.  If the patient is interested, 
the study team will review the informed consent form with them, answer all study 
related questions and obtain written informed consent.  If a patient is not 
interested in the study, the study team will not coerce them into participating; 
participation is completely voluntary. 
 
2.d.    Risks and Benefits 
Participants may or may not benefit from participating in the study.   Benefits of 
participating in the study may include the following: 
1. Improved understanding of diabetes 
2. Improved ability to manage diabetes 
3. Discover glucose patterns previously unaware of. 
Potential risks of participating in the study include the following: 
1. Improperly treated diabetes risks may include:  hypoglycemia, 
hyperglycemia, or ketoacidosis. 
2. CGM sensor insertion risks may include:  feeling like insulin injection; 
tenderness at the sensor site. 
3. Pain, redness, swelling, minor infection and minor bleeding at the 
sensor insertion site. 
4. Redness may occur where the device adhesive pads are placed. 
5. Allergic reaction to one of more parts of the sensor. 
6. Skin may blister or peal at the site of the sensor. 
7. Sensor or insertion needle may break. 
8. Fingerstick testing risks may include:  finger feel sore, tender or may 
bleed. 
9. Questionnaire risks may include:  some questions may cause the 
participant to feel uncomfortable. 
 
2.e.    Early Withdrawal of Subjects  
Participants may be withdrawn if certain situations arise: 
1. Participant does not follow study instructions 
2. Change in participant’s medical condition (i.e., pregnancy, worsening 
clinical condition) 
3. The study team of government agencies stop the study 
4. In the opinion of the study team, there is no value in participant 
continuing the study. 

 
 
 
 
 
 
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5. If new information becomes available or harmful unexpected reactions 
are experienced by participants in the study. 
C3 Study Device  
3.a 
Description  
FreeStyle Libre 2 Continuous Glucose Monitoring System manufactured by Abbott 
 
D Study Procedures  
D1 Screening for Eligibility 
The study team will identify potential participants from patients referred to the 
diabetes service or diabetes education service.  Once a potential patient has 
been identified, one of the study team members will review the 
inclusion/exclusion criteria to determine if the patient is eligible to participate. 
D2 Schedule of Measurements 
 
VISIT/PHONE 
CALL 
(estimated time) 
[window] 
WHAT WILL HAPPEN? 
Screening Visit 
(~45 minutes) 
Review consent form and obtain consent 
Complete questionnaire, obtain diabetes history 
Day of Discharge 
(~1 hour) 
Complete FreeStyle Libre 2 CGM education 
Attach FreeStyle Libre 2 CGM sensor to your arm 
Within 1-3 weeks 
from discharge 
Phone Call 
(~30 minutes) 
 
Questions regarding use of FreeStyle Libre 2 CGM 
Current diabetes regimen 
Adverse Events 
Reminder to take FreeStyle Libre 2 CGM sensor prescription to 
pharmacy to be filled 
1 & 3 Month 
Phone Call 
(~45 minutes) 
[+/- 5 days] 
Questions regarding use of FreeStyle Libre 2 CGM 
Current diabetes regimen 
Complete questionnaire 
Adverse Events 
6 Month 
Phone Call 
(~15 minutes) 
[+/- 10 days] 
Questions regarding use of FreeStyle Libre 2 CGM 
Barriers to FreeStyle Libre 2 CGM use 
 
D3 Visit 1a: During Hospital Stay 
Study team member will meet with participant, review informed consent form and 
obtain written consent.  Study team member will obtain the following information 
from patient or medical record after consent is obtained: 
1. Most recent A1c 

 
 
 
 
 
 
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2. Heigth/Weight; calculate body mass index (BMI) 
3. Year of diagnosis with diabetes 
4. Type of diabetes 
5. Has patient been admitted to the hospital or emergency department in the 
past 3 months for a diabetes related problem 
6. Home diabetes regimen 
7. Hospital diabetes regimen 
8. Hospital discharge treatment regimen 
9. Participant’s reason/goal for using FreeStyle Libre 2 CGM 
10. Does participant have frequent hypoglycemia or hypoglycemia 
unawareness 
11. Complete “Diabetes Self-Management Questionnaire” 
 
D4 Visit 1b:  Day of Hospital Discharge: 
On the day of participant’s discharge from the hospital, one of the diabetes 
educators will complete the following with the participant: 
1. Teach participant how to set up the FreeStyle Libre 2 CGM 
2. Teach participant how to attache the FreeStyle Libre 2 CGM sensor to the 
upper arm 
3. Teach participant how to measure blood glucose with FreeStyle Libre 2 
CGM reader or personal smart phone 
4. Assist participant download the free FreeStyle Libre 2 app from the app 
store on smart phone 
5. Teach participant how to trouble shoot the FreeStyle Libre 2 CGM system 
6. Provide participant with a handout for  FreeStyle Libre 2 CGM system 
 
The study physicians or nurse practitioners will provide the participant with a 
written prescription for three months of the FreeStyle Libre 2 CGM sensors to be 
filled by participant at their local pharmacy. 
D5 Follow Up Telephone Calls  
Within 1-3 Weeks after Discharge: 
The study team will contact the participant by telephone to obtain the following 
information: 
1. Is the participant still utilizing the FreeStyle Libre 2 CGM?  If not, why 
was it stopped? 
2. What barriers (such as discomfort, behavior modifications, lifestyle 
changes, diet changes) did the participant have with the FreeStyle 
Libre 2 CGM to limit use? 
3. How satisfied with the FreeStyle Libre 2 CGM is the participant? 
4. Has the participant been admitted to the hospital or been in the 
emergency department for a diabetes related problem since 
discharge? 
5. Has the participant seen their outpatient diabetes provider since 
discharge? 
6. What is the participant’s current diabetes treatment regimen? 

 
 
 
 
 
 
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7. The study team will contact the participant to remind them to fill the 
prescription for a new FreeStyle Libre 2 CGM sensor with local 
pharmacy. 
 
 
One Month after Discharge (+/- 5 days): 
The study team will contact the participant by telephone to obtain the following 
information: 
1. Is the participant still utilizing the FreeStyle Libre 2 CGM?  If not, why 
was it stopped? 
2. What is the average blood glucose for the past 30 days? 
3. What barriers (such as discomfort, behavior modifications, lifestyle 
changes, diet changes) did the participant have with the FreeStyle 
Libre 2 CGM to limit use? 
4. How satisfied with the FreeStyle Libre 2 CGM is the participant? 
5. Has the participant been admitted to the hospital or been in the 
emergency department for a diabetes related problem since 
discharge? 
6. Has the participant seen their outpatient diabetes provider since 
discharge? 
7. What is the participant’s current diabetes treatment regimen? 
8. Administer the Diabetes Self-Management Questionnaire 
 
Three Months after Discharge (+/- 5 days): 
The study team will contact the participant by telephone to obtain the following 
information: 
1. Is the participant still utilizing the FreeStyle Libre 2 CGM?  If not, why 
was it stopped? 
2. What is the average blood glucose for the past 30 days? 
3. What barriers (such as discomfort, behavior modifications, lifestyle 
changes, diet changes) did the participant have with the FreeStyle 
Libre 2 CGM to limit use? 
4. How satisfied with the FreeStyle Libre 2 CGM is the participant? 
5. Has the participant been admitted to the hospital or been in the 
emergency department for a diabetes related problem since 
discharge? 
6. Has the participant seen their outpatient diabetes provider since 
discharge? 
7. What is the participant’s current diabetes treatment regimen? 
8. Administer the Diabetes Self-Management Questionnaire 
 
Six Months after Discharge (+/- 10 days): 
The study team will contact the participant by telephone to obtain the following 
information: 
1. Is the participant still utilizing the FreeStyle Libre 2 CGM?  If not, why 
was it stopped? 

 
 
 
 
 
 
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2. What barriers (such as discomfort, behavior modifications, lifestyle 
changes, diet changes) did the participant have with the FreeStyle 
Libre 2 CGM to limit use? 
 
E Safety Monitoring 
E1  Safety and Compliance Monitoring 
The study team will meet every other week to review the status of the study, 
progress of recruitment, and adverse events.  The study team will communicate 
directly with one another in between scheduled study team meetings if an 
unexpected adverse event occurs. 
E2  Medical Monitoring  
The study team will monitor patients throughout their participation in the study.  
Any adverse event or unexpected adverse event will be brought to the prinicipal 
investigator within 24 hours of study team notification of event. 
 
F Statistical Plan  
F1 Sample Size Determination and Power 
One hundred patients will be recruited for the study with the anticipation that 50% 
will agree to participate in the study. 
F2 Statistical Methods  
Statistical methods will include descriptive statistics (means, SD, median, IQR) 
and pre-test/post-test ANOVA for the questionnaire. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
 
 
 
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G  References 
 
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Hospitalization of patients with diabetes. Endocr Pract. 1995 Nov-
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monitoring versus usual care in patients with type 2 diabetes receiving 
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YK. Continuous glucose monitoring in older people with diabetes and 
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