Adherence to antihypertensive medication and cardiovascular disease events in hypertensive patients: a dose-response meta-analysis of 2 769 700 participants in cohort study

Background Recently, many studies have investigated the association between adherence to antihypertensive medication (AHM) and risk of cardiovascular disease (CVD) events for hypertensive patients; however, the results varied by different studies. Aims The purpose of our meta-analysis was to explore the comprehensively summarized association between AHM adherence and risk of CVD events in hypertensive patients from cohort studies. Design A dose-response meta-analysis. Methods and results We conducted a systematic search in two databases (PubMed and Embase) from 1974 to 15 December 2019 to identify English-language reports that assessed the association of AHM adherence with risk of CVD events in cohort studies. Pooled relative risks (RRs) and 95% confidence intervals (CIs) were estimated by using a fixed- or random-effects model. Restricted cubic splines were used to evaluate the possible linear or non-linear association. Results We included 16 cohort studies with 2 769 700 participants in the present meta-analysis. The pooled RR of CVD events was 0.66 (95% CI, 0.56-0.78, I-2 = 98.6%) for the highest versus lowest AHM adherence categories. We found a linear dose-response association of AHM adherence and CVD events (P-nonlinearity = 0.887), each 20% increase in AHM adherence was associated with a 13% reduced risk of CVD events (RR 0.87, 95% CI 0.83-0.92, I-2 = 98.2%) in hypertensive patients. Conclusion High AHM adherence has a protective effect on CVD events for hypertensive patients, and improving medication adherence may provide long-term CVD benefits.