Uncontrolled Hypertension Among the Homeless

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.

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