Digital redesign of hypertension management with practice and patient apps for blood pressure control (PIA study): A cluster-randomised controlled trial in general practices.

Background: Long-term hypertension control prevents heart attacks and other cardiovascular diseases, yet implementation is insufficient worldwide. The redesign of hypertension management by information and communication technology (ICT) improved hypertension control, e.g., by transmission of blood pressure (BP) measurements to a central webspace. However, an easy-to-use secure patient app connected with a practice management centre is lacking. This study evaluates the effectiveness of the newly developed PIA (PC-supported case management of hypertensive patients to implement guideline-based hypertension therapy using a physician-defined and -supervised, patient-specific therapeutic algorithm) intervention with PIA-ICT and eLearning for general practices. Methods: The effectiveness of the PIA intervention was evaluated in a cluster-randomised study. Practices were randomly allocated (1:1) to the intervention or the control group (usual care). Group allocation was unmasked for participants and researchers. The primary outcome was the BP control rate (BP < 140/90 mmHg) after 6-12 months. Secondary outcomes included BP changes and satisfaction with PIA-ICT. The trial is registered in the German Clinical Trials Register (DRKS00012680). Findings: Starting from December 1, 2019, 64 general practices were recruited over 1 year during the COVID-19 pandemic. Overall, 848 patients were enrolled between April 15, 2020 and March 31, 2021. The study was completed Sept 30, 2021. At baseline, 636 patients (intervention: 331; control: 305) of 50 general practices met the inclusion criteria. The final dataset for analyses comprised 47 practices and 525 patients (intervention 265; control 260). In the adjusted hierarchical model, the PIA intervention increased the BP control rate significantly by 23.1% points (95% CI: 5.4-40.8%): intervention 59.8% (95% CI: 47.4-71.0%) compared to 36.7% (95% CI: 24.9-50.3%) in the control group. Systolic BP decreased by 21.1 mmHg in the intervention and 15.5 mmHg in the control group. Interpretation: The PIA redesign of care processes improved BP in an outcome-relevant way. Prospectively, it may constitute an important model for hypertension care in Germany. Funding: This study is funded by the German Innovation Fund (Grant number: 01NVF17002).