The study’s primary outcomes were change from baseline in self-reported medication adherence after 12 weeks and change in systolic blood pressure. Adherence was measured using the Morisky medication adherence scale (MMAS) (range, 0-8, with lower scores indicating lower adherence).
At baseline, mean (SD) adherence as measured by the MMAS-8 was 6.0 (1.8) among the intervention arm and 5.7 (1.8) among controls. At the 12-week follow-up, the mean (SD) adherence increased by 0.4 (1.5) in the intervention arm and remained unchanged among controls (between-group difference, 0.4; 95% CI, 0.1-0.7; P = .01).
At baseline, the mean (SD) systolic blood pressure was 151.4 (9.0) mm Hg in the intervention arm and 151.3 (9.4) mm Hg among controls. After 12 weeks of the study, the mean (SD) systolic blood pressure decreased by 10.6 (16.0) mm Hg in the intervention group and by 10.1 (15.4)mm Hg in the control group.
Previous studies indicated that mHealth interventions with SMS or voicemail and immediate physician feedback improved participant blood pressure. This study, however, evaluated a stand-alone app which included reminder alerts, adherence reports, and optional peer support, but no physician involvement.