Adherence to Antihypertensive Medications and Stroke Risk: A Dose‐Response Meta‐Analysis

BACKGROUND: Inconsistent findings have been obtained for previous studies evaluating the association between antihypertensive medication (AHM) adherence and the risk of stroke. This dose‐response meta‐analysis was designed to investigate the association between AHM adherence and stroke risk. METHODS AND RESULTS: MEDLINE and Embase databases were systematically searched to identify relevant studies. The quantification of adherence to AHM was calculated as the percentage of the sum of days with AHM actually taken divided by the total number of days in a specific period. Summary relative risks (RR) and 95% CIs were estimated using a random‐effects model. Stratified and dose‐response analyses were also performed. A total of 18 studies with 1 356 188 participants were included. The summary RR of stroke for the highest compared with the lowest AHM adherence level was 0.73 (95% CI, 0.67–0.79). Stratified by stroke subtype, a higher AHM adherence was associated with lower risks of ischemic stroke (RR, 0.74; 95% CI, 0.69–0.79) and hemorrhagic stroke (RR, 0.55; 95% CI, 0.42–0.72). Moreover, both fatal (RR, 0.51; 95% CI, 0.36–0.73) and nonfatal stroke (RR, 0.52; 95% CI, 0.28–0.94) were lower in participants with higher AHM adherence. The results of a dose‐response analysis indicated that a 20% increment in AHM adherence level was associated with a 9% lower risk of stroke (RR, 0.91; 95% CI, 0.86–0.96). CONCLUSIONS: Higher AHM adherence is dose‐dependently associated with a lower risk of stroke in patients with hypertension.