Effectiveness of mHealth in improving medication adherence among hypertensive patients on follow-up in a tertiary hospital in central Kenya: a randomized controlled trial

Background: Non-adherence to medication is documented in the literature as a major barrier to blood pressure control among patients on treatment for hypertension. This study sought to evaluate the potential effectiveness of a mHealth intervention in supporting medication adherence among hypertensive patients on follow up. Methods: We undertook a single blind parallel randomized controlled trial among hypertensive patients undergoing follow up care in Nyeri County Referral Hospital between January and December, 2020. The trial comprised of two arms, with a total of 120 patients randomized on a 1:1 ratio. Patients in the experimental group were put on an educational health intervention comprising of mobile phone delivered SMS messages and interactive voice calls. Patients in the control group were continued on the usual care offered in the hospital’s medical outpatient clinic. The primary endpoint was medication adherence. Data was analyzed through the intention to treat approach at 5% significance level. Results: A total of 112 participants (93.3%) were retained in the study at the end of follow up. The proportion of patients who were adherent to their prescribed medications was higher by 38.3% among participants in the experimental arm compared to those in the control group (p<0.001). The odds of being adherent to medications was 6.1 times higher for patients who had received the study’s intervention compared to those in the control group (95% CI 2.6, 14.3). Conclusions: The mHealth intervention applied in this study was effective in improving medication adherence among patients on treatment for hypertension.