Lifestyle modifications, including body weight reduction and salt restriction, help reduce blood pressure (BP). This study investigated the effects of body mass index (BMI) and salt intake on home BP reductions in unmedicated patients with hypertension receiving guideline-based lifestyle modification from doctors (control group) or with the addition of a digital therapeutics intervention. Data from the HERB Digital Hypertension 1 (HERB-DH1) pivotal trial were analyzed. Home BP was measured for 7 days before each study visit (baseline, and 4/8/12 weeks). Body weight was measured at each visit and salt intake questionnaire was answered at baseline and 12 weeks. This analysis included 302 patients with sufficient home BP monitoring data (digital therapeutics: 156; control group: 146). The reduction in morning home SBP from baseline to 12 weeks was significantly greater in the digital therapeutics vs. control group for patients with baseline BMI ≥ 25 kg/m2 and higher salt intake group (self-reported salt intake score ≥ 14) (-5.1 mmHg, p < 0.01). Patients in the digital therapeutics group who experienced a reduction in BMI and an improvement in salt intake score during the 12-week study also had a significantly greater reduction in morning home SBP compared with patients in the control group (-7.2 mmHg, p < 0.01). The digital therapeutic intervention reduced home BP the most in unmedicated patients with hypertension with high baseline BMI and salt intake score. Those with improvements in both BMI and salt intake during the digital therapeutics intervention achieved the greatest reduction in home BP vs. control.Clinical trial registration: Japan Registry of Clinical Trials (jRCT2032190148).
Keywords: Body weight; Digital therapeutics; Home blood pressure; Hypertension; Salt intake.
© 2023. The Author(s), under exclusive licence to The Japanese Society of Hypertension.