Blood pressure reduction and all-cause dementia in people with uncontrolled hypertension: an open-label, blinded-endpoint, cluster-randomized trial

Dementia is a leading cause of death and disability worldwide. Here we tested the effectiveness of blood pressure (BP) reduction on the risk of all-cause dementia among 33,995 individuals aged ≥40 years with uncontrolled hypertension in rural China. We randomly assigned 163 villages to a non-physician community healthcare provider-led intervention and 163 villages to usual care. In the intervention group, trained non-physician community healthcare providers initiated and titrated antihypertensive medications according to a simple stepped-care protocol to achieve a systolic BP goal of <130 mm Hg and a diastolic BP goal of <80 mm Hg, with supervision from primary care physicians. Over 48 months, the net reduction in systolic BP was 22.0 mm Hg (95% confidence interval (CI) 20.6 to 23.4; P < 0.0001) and that in diastolic BP was 9.3 mm Hg (95% CI 8.7 to 10.0; P < 0.0001) in the intervention group compared to usual care. The primary outcome of all-cause dementia was significantly lower in the intervention group than in the usual care group (risk ratio: 0.85; 95% CI 0.76 to 0.95; P = 0.0035). Additionally, serious adverse events occurred less frequently in the intervention group (risk ratio: 0.94; 95% CI 0.91 to 0.98; P = 0.0006). This cluster-randomized trial indicates that intensive BP reduction is effective in lowering the risk of all-cause dementia in patients with hypertension. ClinicalTrials.gov: NCT03527719.