Text Messaging and Home Blood Pressure Monitoring for Patients with Uncontrolled Hypertension: Proposal for a Feasibility Pilot Randomized Controlled Trial.

backgroundA decrease in blood pressure, even modestly (ie, 2 mmHg), lowers cardiovascular morbidity and mortality. Low patient adherence to antihypertensive medication is the most significant modifiable patient-related barrier to achieving controlled blood pressure. Preliminary studies have shown that SMS text messaging and home blood pressure monitoring (HBPM) can be effective in promoting medication adherence and blood pressure control. The best strategy to engage with older patients of low socioeconomic status who are low adopters of technology and disproportionally affected by uncontrolled hypertension is still unknown.

objectiveThe objective of this study is to improve blood pressure control in the older, low socioeconomic status population. The study will test two aims: First, we aim to evaluate the feasibility of conducting a randomized controlled trial by using an SMS-based approach among nonadherent, older patients of low socioeconomic status who have uncontrolled hypertension. Feasibility will be assessed in terms of recruitment rates per month (primary outcome); patient acceptability will be evaluated by monitoring retention rates and SMS response rates and using the validated Systems Usability Scale (secondary outcomes). Second, we aim to estimate the effects of the SMS approach on lowering blood pressure and adherence to antihypertensive medications.

methodsWe will recruit 24 patients of low socioeconomic status with uncontrolled hypertension (systolic BP>140 mmHg or diastolic BP>90 mmHg) showing low medication adherence and taking at least two antihypertensives, who have presented to two outpatient clinics of Wake Forest Baptist Health (Winston Salem, North Carolina, USA). Participants will be randomly assigned to either SMS and HBPM (n=12) or usual care and HBPM (n=12) intervention. Clinicians adjusting the patients' medications will be blinded to the study assignment. Text messages will be sent from a secure platform to assess medication adherence and HBPM on a weekly basis. The content and delivery frequency of the proposed SMS intervention are based on input from three focus groups conducted in Spring 2019. Participants in both study arms will receive education on HBPM and using an HBPM device. We hypothesize that we will successfully recruit 24 participants and the intervention will be acceptable to the participants. It will also improve medication adherence (assessed by question Medication Adherence Questionnaire scores) and blood pressure control.

resultsOur study was funded in July 2020. As of May 2021, we have enrolled 6 participants.

conclusionsOur findings will help design a larger efficacy trial to advance the field of eHealth delivery systems particularly for older adults of low socioeconomic status. This study addresses a highly significant topic and targets a population of high morbidity and mortality that has been traditionally underrepresented in clinical trials.

trial registrationClinicalTrials.gov NCT03596242; https://clinicaltrials.gov/ct2/show/NCT03596242. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/18984.