Short Message Service System for Patients With Uncontrolled Hypertension
Phase: NA
Conditions: Hypertension
Sponsor: Wake Forest University Health Sciences

 
Protocol version: 4.30.2020 
 
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Official Title: Short Message Service System for Patients With Uncontrolled Hypertension 
NCT03596242 
IRB-Approved Date:  11/20/20 
 
 

 
Protocol version: 4.30.2020 
 
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Project Title: “SMS patient-centric system for patients with uncontrolled hypertension: a pilot 
study.” 
 
Principal Investigator: Campos Claudia, MD 
Co-investigator(s): Deanna Jones, MD, Justin Moore, PhD Carolyn Pedley, Sara Atwater, 
MD, Beverly Snively PHD and Michael Rocco,MD, MS 
 
Sponsor or funding source: Internal Medicine Departmental Funding 
 
Background, Rationale and Context 
.  
The successful implementation of the new AHA/ACC hypertension (HTN) guidelines based on 
the SPRINT trial findings will reduce risks posed by heart disease and stroke. Heart disease is 
the United States’ leading cause of death.1,2   Low patient adherence to antihypertensive 
medication is the most significant modifiable patient-related barrier to achieving controlled blood 
pressure3. Vulnerable patients have higher blood pressure (BP) and lower adoption rates of 
mobile health (myHealth) technologies. This is particularly prevalent in African Americans, low 
literacy, and older patients (our definition of “vulnerable” populations for this proposal).3-7  
Developing and evaluating myHealth tools to implement clinical guidelines is essential and 
particularly relevant in settings like our clinic, where uncontrolled HTN, poor adherence to 
medications, and no-show rates are exceptionally high. Using SMS to improve adherence is 
logical because of its low cost and widespread use: more than six billion people worldwide have 
access to mobile phones.8  
Medication non-adherence contributes to poor blood pressure control, which can lead to further 
cardiovascular complications including coronary heart disease and heart failure.3,7  
Hospitalization rates are significantly higher in patients with poor medication adherence.9 
Supporting adherence to medical regimens requires insight into patient’s medication-taking 
behavior and their reasons for non-adherence.3,10 Subjective measures of adherence include 
physician reports, self-report, and adherence scales. More objective measures of adherence, 
e.g. electronic monitoring of medication administration, prescription records and dose counts, all 
are expensive, labor-intensive and difficult to incorporate in clinic work flows. However, for this 
project we will use the Medication Adherence Questionnaire (MAQ) because it has been well-
validated to identify adherence among those with HTN, and scores correlate well with a range of 
objective adherence measures.11,12  compliance 
Home blood pressure monitoring (HBPM) appears to reduce BP in patients with HTN, but 
important questions remain regarding effective implementation and which groups may benefit 
most.13,14 In addition, non- with clinic appointments (“no shows”) is a widespread health care 
problem and a missed opportunity for medication adjustment and BP control.3  
Our study team has developed an SMS system based on the input of three focus groups 
composed of minority patients with hypertension. Our goal is to test the patient-centric SMS tool 
to support hypertension management in vulnerable patients seen in the WFBH Internal 
Medicine and Nephrology Clinics. Adopting these new clinical guidelines is imperative to 
achieving better healthcare outcomes.  
The proposed study is distinctive in its ability to recruit and test the implementation in a 
population particularly affected by non- adherence and uncontrolled HTN. To engage patients in 
healthcare is considered a key strategy to improve patients' adherence, clinical outcomes, and 
satisfaction about care received.5,15,16  

 
Protocol version: 4.30.2020 
 
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If it is determined that our system is feasible and efficacious, it could be applied for better care 
of patients with other chronic medical conditions, such as depression or diabetes.  
 
Research Plan 
Objectives 
Our pilot will evaluate the feasibility of implementing an SMS system and HBPM at Wake Forest 
Baptist Health. Implementing a new text messaging service will improve the health delivery 
system in three ways. 1) Increasing patient engagement: SMS and HBPM requires the patients 
to be highly involved and committed to improving their health and results in a marked improvement 
in the adherence to medication. BP measurements has also been reported to improve BP control. 
2) Supporting patients outside of the office visits by identifying and resolving barriers to medication 
adherence earlier on (i.e. if patients are unable to get their prescriptions or are having significant 
side effects). 3) Adopting clinical guidelines to improve BP control in a vulnerable population. 
 
Specific Aims  
Given the high prevalence of uncontrolled hypertension (HTN), testing novel interventions that 
support the implementation of hypertension guidelines may improve access, quality, and health 
outcomes. Although mobile health and text messaging shows promise in other health promotion 
settings, the best strategy to support HTN management in minority non-adherent patients is still 
unknown. 13,14 Thus, the goal of this pilot is to test a patient centric SMS-based text message 
intervention and ensure that it is feasible and acceptable in a sample of minority non-adherent 
patients with hypertension, currently seen in the internal medicine and nephrology clinics at 
WFBH.  
Our long-term goal is to test an automated SMS intervention that can be disseminated and 
implemented to encourage adoption of hypertension guidelines by lowering blood pressure and 
incorporating home blood pressure monitoring in the care of vulnerable patients with 
uncontrolled hypertension. 
The rationale for the proposed pilot is that evaluating an SMS system that considers patients’ 
preferences and identifies barriers to adherence, is of critical importance in a learning health 
care system to transform health delivery, particularly for vulnerable populations. Minority 
populations are usually low adopters of mobile health tools and are most affected by 
uncontrolled hypertension.4,6,17  
Aim 1: Feasibility will be assessed through examination of participant recruitment, retention and 
engagement. Specifically, we will look at the number of participants who refuse to participate in 
the pilot at the time of recruitment and the reason they declined participation. Secondary 
impacts of interest include: medication adherence as measured by the four-item MA 
Questionnaire (MAQ) and change in systolic and diastolic blood pressure at 3 months. 
Aim 2: To test the acceptability of a 3-month SMS-based intervention in adults with uncontrolled 
hypertension. One cohort of 24 participants will be recruited for the SMS intervention. 
Acceptability will be assessed using the systems usability scale (a validated questionnaire that 
measures usability reliably in small samples)18 and eliciting free comments after the survey. 
At the end of this pilot project, we will have preliminary data essential for a future formal efficacy 
trial, to be proposed in a subsequent application to the AHRQ. 
Our first hypothesis is that over 50% of contacted patients will respond to SMS messages and 
over 50% will check HBPM. This estimate is based on previous study by Bobrow and 

 
Protocol version: 4.30.2020 
 
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colleagues in a similar patient population.3 Our second hypothesis will be that > 75% will be 
satisfied with the service (OK or above on the usability survey).9  
 
Methods and Measures 
 
Design 
A randomized control trial of 24 non-adherent participants will be monitored and followed for 3 
months; An ambulatory BP arm device will be provided to all participants with printed 
instructions in English or Spanish (from the American Heart Association) on how to measure BP 
at home (HBPM). Patients will be instructed on checking their BP at least twice a week.14,19  
Text messages will be generated by Twillio platform, keeping a record of participants contacted,  
sent and received texts. Participants in the control arm will receive standard of care education 
for controlling high blood pressure in clinic by their healthcare providers. They will be followed to 
monitor any changes in their BP throughout the duration of the study.  
 
Study team members will identify patients with uncontrolled hypertension during clinic visits. 
Study team members will approach patients 18 years or older who have uncontrolled HTN 
(SBP>130 or DBP >80) and have 2 or more BP medication(s)on their medication list. 
Participants will be interviewed by the study team and those with a MAQ score of 1 to 4 will be 
classified as non-adherent will be invited to participate. The study team member will assess the 
potential participant’s phone ownership, text messaging ability, text messaging willingness, and 
receptivity to the intervention (and record all this information).The MAQ cut-off was chosen for 
the study because it has been used in the literature in previous studies,20-22  and the cut-off at 
this value provides a highly sensitive tool for identifying medication non-adherence. 22,23  
Participants will be randomized into one of two groups: intervention SMS arm or the control arm. 
If enrolled in the intervention arm, the subjects will be contacted by phone via SMS and phone 
call. To ensure equal access to participation among women and minorities we will translate all 
materials and questions to Spanish. The privacy of potential subjects during recruitment will be 
protected by collecting only necessary identifiers and using a private room during the interview 
process.   
As part of routine care, patients who present to the office with uncontrolled HTN receive 
instructions from their clinician on medication changes and are advised to return for a nurse visit 
in 2 weeks and a clinician visit in 3 months. During follow-up, the nurse checks the patient’s 
blood pressure and contacts the clinician for further management if the BP is not controlled. 
Participants in the SMS arm will receive SMS messages to monitor their blood pressure in 
addition to this routine care whereas the control arm will only receive the standard provider 
education and monitoring for controlling blood pressure. 
Baseline demographic characteristics of the participants will be collected. Participants will be 
followed with office (or phone if they no show for their visit) interviews at 2 weeks or 3 months to 
complete 2 validated scales: the MAQ, and SUS+ free comments  
Study intervention participants will be provided with a blood pressure monitor to be used for 
measurement and extraction of HBPM information. Clinicians will be alerted through an in-
basket message in the electronic medical record (Wake One) if the participants report BP 
outside the threshold range, and the patient will be sent an SMS and prompted to contact their 
clinic. The threshold range set for SBP is between 90 and180 mm Hg and between 60 and 110 
mm Hg for DBP for one-time measurements, These thresholds are made based on the 

 
Protocol version: 4.30.2020 
 
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recommendations by HTN guidelines, which designate  a hypertensive urgency to be 180/110 
mm Hg or higher and hypotension 90/60 or lower.2  
Patients who no show to the follow up visits will be telephoned to assess adherence barriers. 
The study team member will create a telephone encounter in the electronic health record to 
document their discussion and route it to the patient’s PCP. Patients who refuse participation in 
the study will be asked for the reason and their responses will be recorded to determine any 
barriers to participation. Study team members will attempt to contact patients who miss follow 
up visits every week up to 3 times, if after the 3rd time the patient is still not able to be reached, 
the patient will be lost to follow up. 
 
Setting 
The study team will recruit patients who fall within the eligibility criteria from Wake Forest Baptist 
Medical Center. 
 
Subjects selection criteria 
 
Eligibility and recruitment 
Inclusion criteria 
Patients 18 years and older who have SBP>130 or DBP >80 during an office visit encounter in 
the past 6 months and have BP medication(s) on their medication list.  
• 
Own a phone with SMS capability 
• 
Non-adherent-MAQ score of 1 to 4 
• 
Vulnerable population (Black, Hispanic or education level < or equal high school (as an 
indicator of low SES) 
Exclusion Criteria 
• 
End-stage renal disease (on hemodialysis or peritoneal dialysis) 
• 
Kidney transplant recipients 
• 
Unable to afford BP medications or lack transportation to clinic visits 
• 
Hospice or nursing home care 
• 
Dementia or cognitive impairment on the problem list 
 
Sample Size 
 
24 patients –We will randomize 12 patients into 2 groups 
Interventions and Interactions 
 
 
Pilot randomized controlled study.  
 
Participants in the SMS intervention arm will receive usual care and SMS texting and phone 
calls. Study team members will send secure SMS messages to participants weekly for four 
weeks and then every other week until their next appointment. 

 
Protocol version: 4.30.2020 
 
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 The secure messaging system will be as follows 
Introductory message: 
Welcome to managing your blood pressure with the Nephrology/ Internal medicine clinics at 
Wake Forest. Try to take your BP meds at the same time every day to keep your BP under 
control! Make it part of your daily routine: 
First week 
Adherence checkpoint: 
1. Good morning! Did you take your blood pressure medications today? 
“No” Response: 
1. Let’s try to stay on top of taking them daily! You can do this! 
Additional prompts: 
Did you fill your prescription?  
- 
 
-If no -> phone call to determine barrier to filling BP meds “Mr./Mrs. (X). My name 
is (Y), we met when you were in the 7th Janeway clinic.  I am calling you to find out if 
you are having difficulties filling your prescriptions. I will let Dr. (Name) know. Have you 
tried our pharmacy?” Message clinician in Wake One. 
- 
            If yes 
- 
Did you have any side effects from your blood pressure medication? 
- 
 
-If yes -> phone call to determine side effects 
- 
Mr./Mrs. (X). My name is (Y), we met when you were in the 7th Janeway clinic.  I am 
calling you to find out if you are having side effects from your blood pressure 
medications. I will let Dr. (Name) know. Message clinician in Wake One.  
- 
          - If No, no action 
“Yes” Response: 
1. Keep it up! Plus thumbs up emoji 
 
Self-monitoring phase: 
1. Have you been checking your BP? We’ll be checking in tomorrow for results! 
“Yes” Response: 
1. Nice work! 
Additionally: 
What was the top number (SBP)?  
 
What was the bottom number (DBP)? 
“No” Response: 
1. Never too late to start! Try checking your BP in the AM and PM every day for the next 
few days and we’ll check back again later. 
Data Response/Gamification: 
1. BP measurements received. You’re doing great! Keep it up – you’re currently in X place 
among texters.  
 
 
An adapted version of the System Usability Scale (SUS) by  Bangor9 will be administered either 
in person or the phone after the follow up clinic visit or at the end of week 12 (if patient misses 
follow up appointment). 
 
Study team members will perform the following tasks to track study participants progress: 

 
Protocol version: 4.30.2020 
 
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1. Weekly tracking of number of patients contacted and who responded to SMS, number of 
SMS questions answered, and number of office visits completed 
2. Monthly tracking of patient satisfaction surveys  
3. Monthly reports distributed via email to the team providing ongoing feedback on 
performance related to patient outreach and patient satisfaction  
4. When high or low BP is reported SBP > 180 or <90 and or DBP > 110 or <60, a study 
team member will send a message in Wake One to the clinic triage nurses.  The triage 
nurse will contact the patient to arrange a clinician office visit or a nurse blood pressure 
check appointment based on additional information on clinical symptoms. 
 
 
Outcome Measure(s) 
A- Feasibility 
Feasibility will be assessed consistent with the recommendations of Leon and colleagues.24  
Specifically, we will examine: 
1. Screening: we will track the number of patients screened per month, the number 
enrolled per month, the proportion that are eligible who enroll. 
2. Recruitment: number of participants who refuse to participate in the pilot at the time of 
recruitment and the reason why. Proportion of vulnerable patients screened but 
excluded because they did not own a phone with SMS capability. 
3. Retention: the proportion of participants who continue to use the myHealth tool per 
month through three months will be tracked for the intervention. 
4. Engagement: 12- SMS rate response of at least one home BP measurement. We will 
use  44% as our cut off based on an SMS study by Peters and colleagues25. 
Finally, we will monitor time needed for assessments and gather feedback on the participant 
burden. 
 
B-Acceptability 
Participants will complete the SUS in person on an I-Pad or over the phone. They will also be 
offered the opportunity to comment in their questionnaires about their experiences of taking part 
in the pilot. The SUS yields a single score on a scale of 0–100. A SUS score above a 68 would 
be considered above average. We will consider acceptable when >70 % of participants score 
the SUS above 68.26  
 
Secondary measures of interest 
Medication adherence (MA) will be measured by administrating the four-item MAQ by the study 
coordinator during enrollment and at 3 months follow up visit. The MAQ was selected because it 
has been well-validated to identify adherence in HTN and scores have been shown to correlate 
well with a range of objective adherence measures.11,12   
SBP and DBP change at 3 months. BP will be measured during initial and follow up office visits 
by nurses or clinicians while patient is seated with automated arm devices according to 
standard office procedures. We will extract from the electronic medical record, SBP and DBP at 
enrollment and at 12 weeks follow up. The average change will be calculated and reported in 
mmHg. 

 
Protocol version: 4.30.2020 
 
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No-show rate at 3 months’ follow-up (f/u) clinic visits. If participants fail to come to their f/u visits 
within 7 days of their scheduled follow-up appointment, they will be considered as “no- shows”. 
Our current clinic no-show rate is 30%, therefore if the study participants no-show rate is less 
than 30% we will consider our tool a feasible intervention. 
 
Analytical Plan 
Results will be analyzed initially using descriptive statistics.  Comparison between groups will be 
done using chi square tests for proportions, and t-tests for continuous variables.  Regression 
analysis will be performed to identify independent outcome predictors. RedCap will be utilized to 
collect all patient data.  Participant’s demographics (including education level), co-morbidities, 
number of medications, number of blood pressure medications and BP numbers will be 
extracted from Wake One when available. Level of education will be confirmed verbally with 
each participant during consent process. Only one participant identifier will appear in the data 
collection forms. 
   
The full analysis set will include participants who have responded to at least one SMS message 
post-randomization. Descriptive statistics will be computed for each treatment group; medians 
and percentiles will be reported for skewed continuous variables. For primary and secondary 
outcomes, descriptive statistics and 95% confidence intervals will be used to summarize the 
differences between groups. The secondary outcome of BP and other continuous variables will 
be assessed with a repeated-measures analysis using a mixed linear model approach. The 
Wilcoxon rank sum test will be used to compare MA between groups. Hypothesis tests will be 2-
sided using the 0.05 significance level. Bonferroni-type adjustments for multiple testing will be 
implemented to control type I errors. Statistical analysis will be performed using SAS software 
(SAS Institute, Cary, NC). 
  
Treatment assignment will be determined using blocked randomization 
The primary analysis will consist of all subjects who responded with at least one BP 
measurement 
 
 
 
 
 
 
 
Human Subjects Protection 
 
Subject Recruitment Methods 
 
Subjects will be identified when they come to an office visit and their blood pressure is not well 
controlled. The PI clinician (internal medicine preceptors or residents) will verbally alert the 
study coordinator on site of possible participants based on BP >140/90. The study team 
member will meet the patient in a private room in 7th Janeway, determine eligibility, and signed 
informed consent will be obtained from each subject. Once enrolled, the subjects will be 
contacted by phone via SMS and phone call. To ensure equal access to participation among 
women and minorities we will translate all materials and questions to Spanish. The privacy of 

 
Protocol version: 4.30.2020 
 
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potential subjects during recruitment will be protected by collecting only necessary identifiers 
and using a private room during the interview process.   
 
 
Informed Consent  
The study team will recruit patients in the renal and internal medicine clinics. Signed informed 
consent will be obtained from each subject. Participants will be consented in a private room in 
the clinic. Group assignment will be determined using blocked randomization. 
Participants will either receive an educational pamphlet or use their own mobile phone to 
communicate with the study coordinator via SMS. HIPAA-compliant SMS text messages will be 
sent to participants through any of the local mobile phone network providers.  
 
Confidentiality and Privacy 
Confidentiality will be protected by collecting only information needed to assess study 
outcomes, minimizing to the fullest extent possible the collection of any information that could 
directly identify subjects, and maintaining all study information in a secure manner.  To help 
ensure subject privacy and confidentiality, only a unique study identifier will appear on the data 
collection form.  Any collected patient identifying information corresponding to the unique study 
identifier will be maintained on a linkage file, stored separately from the data.  The linkage file 
will be kept secure, with access limited to designated study personnel.  Following data collection 
subject identifying information will be destroyed after three years using a shredder, consistent 
with data validation and study design, producing an anonymous analytical data set.  Data 
access will be limited to study staff.  Data and records will be kept locked and secured, with any 
computer data password protected.  No reference to any individual participant will appear in 
reports, presentations, or publications that may arise from the study.  To prevent breach of 
confidentiality on subject’s cell phone device the study team will ensure the subject is aware of 
the configuration feature on the device to only show text messages upon unlocking the phone.   
 
Data and Safety Monitoring 
The principal investigator will be responsible for the overall monitoring of the data and safety of 
study participants.  The principal investigator will be assisted by other members of the study 
staff.  
 
Reporting of Unanticipated Problems, Adverse Events or Deviations 
Any unanticipated problems, serious and unexpected adverse events, deviations or protocol 
changes will be promptly reported by the principal investigator to the IRB and sponsor. 
 
  
 
 
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