Abstract Body (Do not enter title and authors here): Background: Digital therapeutics (DTx) for hypertension are one of the most promising hypertension treatments with proven antihypertensive effects. In this study, we investigated the predictors and prediction score of the home blood pressure (BP) lowering effect of DTx using the prospectively collected data on a daily basis.
Methods: The B-INDEX is a multicenter intervention study with 6-month DTx, followed by 6 months without DTx in hypertensive patients. Home BP (morning and evening), body composition, physical activity, and sleep state were monitored using digital devices on a daily basis. This first report of the B-INDEX study analyzed data during a 6-month DTx treatment period.
Results: A total of 198 hypertensive patients (mean age 54.9±10.6 years, 57.1% male, mean body mass index 26.7±5.3 kg/m², 57.6% taking antihypertensive medication) were included in the analysis. A marked BP reduction was observed in the first 4 weeks (morning home BP: -6.2/-2.6mmHg). Mixed model analysis demonstrated that baseline home BP, older age, self-efficacy score, reduction of self-reported salt intake, and a mild initial drop of body weight (-500 g at week 4) were significant efficacy predictors of 6-month home BP reduction. The efficacy prediction score based on these predictors demonstrated a 10.2 mmHg difference in the home systolic BP reduction between higher vs lower score groups at week 24.
Conclusions: Older age, salt reduction, and initial weight loss were predictive factors for effective BP reduction by DTx, independent of baseline BP values. We propose that the first 4 weeks are the key period for hypertension treatment with DTx.