Heterogeneous associations of a mobile health-based disease management program on uncontrolled hypertension: A target trial emulation study

Long-term effectiveness of digital health interventions for hypertension remains unclear, particularly regarding individual variability in treatment response. This study examined the association of a mobile health-based disease management program for uncontrolled hypertension and assessed treatment effect heterogeneity using a target trial emulation framework. We analyzed health checkup data of employees June 2021–December 2023. Individuals with hypertension, diabetes, or dyslipidemia were invited to participate in a six-month mobile health-based disease management program incorporating lifestyle tracking via a mobile application and remote behavioral coaching. We compared the following two treatments using a target trial emulation framework: mobile health-based disease management program combined with conventional treatment, versus conventional treatment alone. The primary outcome was uncontrolled hypertension at the one-year follow-up (systolic ≥140 mmHg or diastolic ≥90 mmHg). We estimated average and individual treatment effects using outcome regression based on the G-formula with ensemble machine learning methods for model specification. Clustering analysis was used to identify heterogeneous subgroups and potential effect modifiers. Mobile health-based disease management program was associated with a 5.2% (95% confidence interval: 4.4% to 6.0%) lower prevalence of uncontrolled hypertension compared with conventional treatment. Treatment response varied, with greater benefits observed in individuals with a strong intention to improve lifestyle habits, higher diastolic blood pressure, and more favorable behavioral and metabolic characteristics. Age was associated with benefit, though it had relatively lower importance. Participation in a mobile health-based disease management program was associated with better blood pressure control over one year. The substantial variation in treatment effectiveness highlights the need for personalized digital health strategies.Author summary: This study examined whether a mobile health program can help maintain blood pressure control over one year, and whether benefits differ across individuals. Employees in Japan were invited to use a mobile app to track daily habits—such as weight, activity, diet, and blood pressure—and to receive remote coaching from health professionals; outcomes were compared with those receiving standard care only using methods from causal inference to make the comparison as fair as possible. After one year, about 5% fewer participants in the mobile health program had uncontrolled hypertension compared with those receiving standard care alone. Benefits were not uniform: individuals who already intended to improve their lifestyle, who began with higher diastolic blood pressure, and who showed more favorable day-to-day habits and routine health measures tended to benefit more. By contrast, age was linked to benefit but played a smaller role than these modifiable factors. These findings suggest that mobile health can meaningfully support blood pressure control and that tailoring program intensity and content to each person’s readiness and needs may enhance effectiveness.