Effectiveness of a multi-component intervention strategy on blood pressure control among older patients with hypertension: a target trial emulation

Hypertension is a significant health risk in older adults and remains inadequately controlled in low- and middle-income countries (LMICs). Limited information is now available on the effectiveness of multicomponent interventions in older patients with hypertension. A multicomponent intervention was conducted in Kaihua county, with participating patients as the intervention group. Patients from Changshan county, where no intervention was conducted, were selected as the control group using a two-stage propensity score matching. The primary outcome was the difference in blood pressure (BP) changes from baseline to end of follow-up. Secondary outcomes included medication adherence rates, BP control rates, and difference in the risk of cardiovascular and cerebrovascular diseases (CVDs). Additionally, the spillover effects of the intervention were delved into. From baseline to 24th month, compared to the control group, the net reductions were 1.190 mmHg in systolic BP (95%CI 0.774 to 1.605; P < 0.001) and 0.376 mmHg in diastolic BP (95%CI 0.143 to 0.503; P = 0.004). Besides, the intervention group showed a 2.76% increase in achieving BP control, along with improved regular medication adherence (P < 0.001) and a reduced risk of CVDs (HR = 0.759; 0.647 to 0.892; P = 0.001). Moreover, non-participating patients in the intervention areas also experienced lower systolic BP (2.094 mm Hg; 95% CI 1.421 to 2.766; P < 0.001) and reduced risk of CVDs compared to those in Changshan due to passive interventions (HR = 0.541; 0.407 to 0.718; P < 0.001). The multicomponent intervention effectively reduced BP in hypertensive patients, with significant spillover effects within the non-intervention population. This feasible, effective, and sustainable strategy is recommended for replication in LMICs.