Bidirectional Text Messaging for Measurement and Motivation of Medication Adherence in Hypertension, a Pilot Study

The goal of this pilot study is to test different approaches to monitor medication adherence in hypertension patients, leveraging the NIH-funded Way to Health platform. Patients with poor blood pressure control will be recruited from the University of Pennsylvania Health System and offered remote monitoring with electronic pill bottles or bidirectional text messaging. Our aim is to analyze and compare the effects of remote monitoring with electronic pill bottles versus bidirectional messaging on blood pressure reduction after 4 months.

Patients will be randomized 2:2:1 to Arm A (electronic pill bottle), Arm B (bidirectional messaging), and Arm C (usual care). A total of 150 participants will be enrolled in the study, with 60 in each intervention arm and 30 in the control. After 4 months all patients will complete an in-person follow-up blood pressure measurement and end of program survey. We will monitor all patient's medical records for an additional 8 months after the intervention to track blood pressure measurement and number of outpatient visits.

Accrual: Participants in this study will be patients being treated within the UPHS health system. They will be identified via daily electronic medical records review by our study staff. The study staff will work with UPHS to create a filter for the electronic medical record system that will generate a monthly list of patients who may meet the study criteria. A study coordinator will review the list of patients to determine eligibility. If patients meet the minimal requirements they will be added to the study screening data base and contacted via recruitment letter and up to 3 follow-up phone calls. The intervention of the study will be 4 months from date of consent, and an additional 8 months of follow-up, passively monitoring visit utilization and blood pressure in the electronic medical record. After a patient enrolls a message will be sent to their PCP via EPIC to notify their physician that their patient is enrolled in our study. At the conclusion of the intervention, participants will complete an in-person blood pressure measurement and post-study survey. Information about BP measurements will be recorded in EPIC and message will be sent to the PCP with the research BP measurement included.

Analysis Plan: The primary outcome will be the systolic blood pressure during the 4 month visit, controlling for the initial systolic blood pressure. Additional outcomes include, percent that are normotensive, recruitment and attrition rates, and patient perceptions about intervention from survey. We will also track BP measurements from the EMR that is obtained through usual care as well as utilization of PCP visits, MPM messaging, and phone calls. We will also compare medication adherence between patients with the electron pill bottles and the patients with bidirectional messaging. Assuming 5.3mmHg standard deviation of SBP (given variability of BP over time) and a two-sided significance level of 0.017 (to accommodate the three pairwise comparisons), our sample size of 60 in each intervention arm and 30 in the control arm provides 80% power to detect a difference in SBP reduction of 3.75 mmHg between either intervention and usual care, and a difference in SBP reduction of 3.1 mmHg between the electronic pill bottle and bidirectional text messaging arms.

Data Safety: Paper-based records will be kept in a secure location and only be accessible to personnel involved in the study. Computer-based files will only be made available to personnel involved in the study through the use of access privileges and passwords.