Uncontrolled Hypertension Among the Homeless

mHealth to Address Uncontrolled Hypertension Among Hypertensive Homeless Adults

This study is designed to assess the effect of implementing a mobile health (mHealth) strategy using text messaging for hypertension (HTN) management among hypertensive homeless persons with uncontrolled blood pressure age 21 or older in shelter-clinics in New York City (NYC). The study uses a randomized clinical trial design (homeless, n=120) and semi-structured interviews (homeless, n=30; providers, n=20).

The control group will receive text messages for usual standard care/healthy lifestyle during a 6-month follow-up period. The intervention group will receive text messages geared towards both standard care/healthy lifestyle and blood pressure control. At the end of study period, the investigators will assess changes in blood pressure (BP) measurements, adherence to clinic visits, and adherence to medication, and the investigators will compare them between the two groups. Qualitative interviews with both patients and providers who provide services to the homeless in shelter settings will develop a better understand barriers and opportunities regarding BP control. The investigators hypothesize that those individuals randomized to the intervention will experience a reduction in blood pressure (8mmHg systolic BP or diastolic BP) and will exhibit better adherence to blood pressure medications and appointments compared to the control group.

Study Overview

• Status: Completed
• Conditions: Hypertension
• Intervention / Treatment: Behavioral: mHealth for Hypertension in Homeless Persons

Detailed Description

Project Renewal operates several urban shelters in five boroughs of NYC. Enrollment, data collection, and retention will be supported at these sites.

Patient participants will be recruited in clinics via medical record reviews and will be randomly assigned to treatment groups using a computer-assisted permuted randomization schedule with a block size of four, stratified by clinic site, severe mental illness, and active substance use disorder. Provider participants are physicians, nurse practitioners, social workers, and counselors working at Project Renewal.

The intervention will include 6 months of mHealth HTN management support via short message service (SMS) texts including reminders for medication adherence, appointment attendance, and HTN-specific health education and support. Texts will be delivered to support medication adherence and lifestyle changes, and participants will receive appointment reminders before each appointments. The control group will receive 6 months of mHealth including basic healthcare and general health promotion via SMS texts on the same schedule as the intervention group. Both groups will undergo BP measurements and adherence assessments at appointments in the shelter-clinics. All texts will be interactive and reciprocal; during the study, feedback to SMS texts, including automated and reciprocal feedback for patient-specific input, will be directly provided to patients to enhance education and behavioral changes.

Primary outcome measures will be recorded at 0, 2, 4, and 6 months, and secondary outcome measures will be collected throughout the study. Qualitative interviews with persons experiencing homelessness with HTN (n=30, 15 each arm) and providers (n=20) will be conducted at the end of the recruitment period. Trained research assistants (RA) will collect data and perform the semi-structured interviews.

During clinic visits, BP will be measured by trained clinic nurses in a seated upright position on the right arm with a properly sized cuff. Two readings will be taken at 2-minute intervals following 5 minutes of rest and will be averaged and recorded. Proportion of days covered (PDC) and pill counts will be conducted at each visit. Additional information, including appointment attendance, will be collected from the medical record.

• Study Type: Interventional
• Enrollment (Actual): 123
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • District of Columbia
    • Washington D.C., District of Columbia, United States, 20052
      • George Washington University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 21 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Currently experiencing homelessness
• Current diagnosis of hypertension
• SBP above 140mmHg or DBP above 90mmHg at most recent clinic visit
• English or Spanish speaking
• Currently presenting to Project Renewal shelter-clinics for medical care
• Connected to multidisciplinary social and health services at Project Renewal

Exclusion Criteria:

• Pregnant or within 3 months post-partum
• Heart attack or stroke within previous 6 months
• History of aortic aneurysm
• Diagnosis of end-stage renal disease or currently on dialysis
• Inability to read or respond to SMS texts
• Any condition preventing participants from providing informed consent
• SBP >175mmHg or DBP >105mmHg unless medical provider determines patient has no symptoms suggesting a hypertensive emergency or urgency

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Health Services Research
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Hypertension-Specific Education; 6 months of mHealth HTN management support via SMS texts including reminders for medication adherence, appointment attendance, and HTN-specific health education and support. Texts will be delivered to support medication adherence and lifestyle changes, and participants will receive appointment reminders before each appointments with a follow-up text and robocall if the appointment is missed.	Behavioral: mHealth for Hypertension in Homeless Persons; SMS text messages sent to participants' mobile phones
Other: General Health Education; 6 months of mHealth including basic healthcare and general health promotion via SMS texts. Blood pressure measurements and adherence assessments will be collected at every shelter visit.	Behavioral: mHealth for Hypertension in Homeless Persons; SMS text messages sent to participants' mobile phones

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Blood Pressure	Systolic and diastolic blood pressure readings (SBP and DBP)	6 months
Medication Adherence	Medication adherence was measured using the Voils 3-Item DOSE-Nonadherence measure, a 5-item Likert scale. This was measured by dichotomizing the response options such that any score of 2-5 on any of the three Extent of Non-adherence items is considered non-adherent (e.g., code as 1), and a response of 1 (none of the time) on all items is considered adherent (e.g., code as 0). The extent of adherence was then reported as a median percentage of the total participants with an IQR range as reflected below.	Overall over 6 months
Appointment Attendance	Percentage of appointments attended	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants Who Completed Interviews	The number of interviews that were completed concerning participants' experiences. All data obtained are qualitative.	6 months

Collaborators and Investigators

• Sponsor: George Washington University
• Collaborators: New York University; National Institute on Minority Health and Health Disparities (NIMHD)
• Investigators: Principal Investigator: Ramin Asgary, MD, MPH, George Washington University

Publications and helpful links

General Publications

• Asgary R, Bauder L, Naderi R, Ogedegbe G. SMS text intervention for uncontrolled hypertension among hypertensive homeless adults in shelter clinics of New York City: protocol for a pragmatic randomised trial study. BMJ Open. 2023 Oct 30;13(10):e073041. doi: 10.1136/bmjopen-2023-073041.

Study record dates

Study Major Dates

• Study Start (Actual): September 12, 2022
• Primary Completion (Actual): September 15, 2025
• Study Completion (Actual): September 30, 2025

Study Registration Dates

• First Submitted: December 7, 2021
• First Submitted That Met QC Criteria: December 21, 2021
• First Posted (Actual): January 11, 2022

Study Record Updates

• Last Update Posted (Estimated): October 27, 2025
• Last Update Submitted That Met QC Criteria: October 24, 2025
• Last Verified: October 1, 2025

More Information

Terms related to this study

• Keywords: Hypertension; blood pressure; mHealth; medication adherence; texting; Homeless Persons; Short message service
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Behavior; Treatment Adherence and Compliance; Health Behavior; Patient Compliance; Patient Acceptance of Health Care; Hypertension; Medication Adherence; Health Services Administration; Delivery of Health Care; Patient Care Management; Telemedicine
• Other Study ID Numbers: NCR203140; 1R21MD016201-01 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No