Does App-based Self-monitoring of Hypertension-related Behaviours Reduce High Blood Pressure?:A Systematic Literature Review with Meta-analyses (Preprint)

BACKGROUND Self-monitoring of behaviour can support lifestyle modifications; however, we do not know whether such interventions are effective in reducing blood pressure in patients with hypertension. OBJECTIVE This systematic review evaluates the extent to which app-based self-monitoring interventions support reductions in blood pressure and changes in hypertension-related behaviours. METHODS A systematic search of six databases identified 4637 articles, of which 226 were included for full text screening. Article screening, study and intervention coding, and data extraction were completed independently by reviewers. Fourteen randomised controlled trials were included in the review. RESULTS In total 7,365 patients with hypertension were included in the meta-analyses. Results showed that app-based behavioural self-monitoring interventions had a small but statistically significant effect in reducing systolic blood pressure (mean reductions MD=1.57 mmHg 95%CI 0.49 mmHg to 2.66 mmHg and OR=1.60 95%CI 0.74 to 3.42), and in improving medication adherence (mean improvements SMD=0.78, 95%CI 0.22 to 1.34 and OR=3.83, 95%CI 1.25 to 11.76) as an adjunct to usual or enhanced usual care. The review found no effect of interventions in supporting improvements in physical activity, diet, or smoking behaviours. Most interventions consisted of features to enable participants receive feedback on reported health behaviours, report and monitor blood pressure, receive advice by health care providers following the measurements of health behaviours, and many provided tailored support. A subgroup analysis found that tailored self-monitoring behavioural interventions resulted in higher and significant reductions in both systolic and diastolic blood pressure in comparison to non-tailored interventions (SBP = - 2.87 mmHg 95% CI -3.90 to -1.85 vs. SBP = - 0.72 mmHg 95% CI -1.67 to 0.23, Chi2=9.15, P=0.002; DBP = -2.05 mmHg 95% CI -3.10 to -1.01 vs. DBP = -1.32 mmHg 95% CI -2.26 to -0.39, Chi2=9.19, P=0.002). CONCLUSIONS Tailored self-monitoring of hypertension-related behaviours via smartphone apps have modest but clinically significant effects in reducing blood pressure. Future studies should use rigorous methods to explore their effects at supporting changes at both blood pressure and hypertension-related behaviours to inform health care practice. CLINICALTRIAL not applicable