OBJECTIVE: To evaluate the effects of mobile apps with tailored recommendations on changes in blood pressure (BP) and drug adherence. PATIENTS AND METHODS: This study is a randomized, open-label, multicenter trial to evaluate the efficacy of self-monitoring of BP (SMBP) with a mobile application-based feedback algorithm (SMBP app with feedback) compared with SMBP alone. Patients with uncontrolled hypertension aged 19 years or older were randomly assigned. In the control group, the patients only measured their BP at home using the mobile app combined with a Bluetooth BP monitor and received standard care, whereas in the intervention group, the patients could also receive alerts for BP measurement and additional recommendations from the app using a feedback algorithm in response to the obtained BP value. The primary end point was the change in mean home systolic BP at 24 weeks. RESULTS: From September 1, 2019, through July 8, 2020, 184 patients were randomized into 2 groups: SMBP app with feedback (n=97) and SMBP alone (n=87). At 24 weeks, the mean ± SD home systolic BP reduction from baseline was significantly greater in the SMBP app with feedback group than in the SMBP alone group (-22.4±13.5 vs -17.2±13.3 mm Hg
P=.02). The SMBP app with feedback group had higher drug adherence and proportion of adherence of 95% or greater than the SMBP alone group. CONCLUSION: The SMBP app with feedback is superior to SMBP alone in terms of systolic BP reduction and improved drug adherence in patients with hypertension. Given the high cost of traditional interventions between patients and health care professionals, feedback through mobile apps could potentially be a useful tool in the management of hypertension. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT04470284.