Blood pressure-lowering drugs and secondary prevention of cardiovascular disease: systematic review and meta-analysis.

OBJECTIVE: To systematically evaluate the efficacy of five commonly used blood pressure-lowering drugs in reducing cardiovascular events among patients with nonacute cardiovascular disease, but without heart failure.

METHODS: We searched PubMed, EMBASE, and Cochrane Central Register of Controlled Trials on 18 March 2017. The primary outcome was fatal and nonfatal cardiovascular events, and the secondary outcomes were all-cause death, fatal and nonfatal myocardial infarction, and stroke. Pooled risk ratios and corresponding 95% confidence intervals (CIs) were calculated using Mantel-Haenszel random-effects meta-analyses.

RESULTS: Twenty-seven randomized controlled trials with 143 095 participants and a treatment duration of at least 12 months were included in our analyses. Fifteen trials enrolled patients with coronary artery disease, eight enrolled patients with cerebral artery disease, and four enrolled patients with cardiovascular disease. Of the 27 trials, 10 trials only included hypertensive patients. Compared with placebo, angiotensin-converting enzyme inhibitors (ACEIs) (risk ratio 0.85, 95% CI 0.78-0.92), angiotensin receptor blockers (risk ratio 0.92, 95% CI 0.87-0.98), and diuretics (risk ratio 0.77, 95% CI 0.66-0.90) significantly reduced the risk of cardiovascular events. Apart from this, ACEIs significantly reduced all secondary outcomes, calcium channel blockers, and diuretics reduced stroke significantly. No significant difference was found in head-to-head comparisons of each given drug class with any other class.

CONCLUSIONS: Although only ACEIs have evidences showing its effect in reducing cardiovascular events and all secondary outcomes, head-to-head comparisons did not provide strong evidence in difference in the effects between these blood pressure-lowering drugs.