Engaging Religious Leaders to Reduce Blood Pressures in Rural Tanzanian Communities: A Cluster Randomized Trial

Objective: Partnerships with religious leaders (RLs) can positively change health behaviour. We conducted a cluster randomized trial in NW Tanzania to determine whether empowering RLs to engage their communities about blood pressure (BP) can reduce mean community BP.Design and method: We randomized 10 Tanzanian communities to receive the Religious Engagement in Health intervention and 10 to the control arm. In intervention communities, six RLs from each church or mosque were invited to attend a 2-day seminar about BP. RLs were equipped to provide BP teaching and measure BP both in their religious institutions and communities. The primary outcome was the change in mean systolic BP from pre-intervention to 12 months post-intervention, comparing intervention and control arms, with different randomly selected community members at each time point. Secondary outcomes included diastolic BP, body mass index, waist circumference, physical activity, and awareness/treatment for hypertension. Results: Of 164 communities assessed, 49 met eligibility criteria and were stratified by size and randomly ordered. Twenty communities were randomly selected and randomized. Baseline primary and secondary outcome measures were assessed beginning March 2023 in intervention and control community pairs, and the intervention was delivered between April 2023 and April 2024 as soon as the baseline assessment was completed in the intervention community. Twelve months after the intervention, the mean reduction in systolic BP was 0.5mmHg (95% CI: -1.9,0.8; p=0.45) greater in the intervention versus control communities. No improvements in secondary outcomes were observed (Table 1). In intervention communities, a considerable proportion of randomly selected people reported receiving education about BP from RLs (29.5% vs. 0.3% in control communities at 12 months). Interviews with RLs and community members confirmed that RLs enthusiastically implemented BP education and screening in their religious institutions but struggled to connect people with high BP to treatment at local clinics. Conclusions: Our Religious Engagement in Health Intervention did not improve BP or related risk factors at a community level, despite increased teaching about BP in intervention communities. Additional efforts to strengthen linkage to care and treatment initiation and maintenance are needed.