Aspirin for primary prevention of cardiovascular disease
Abstrakt
BACKGROUND: Platelet inhibition by aspirin reduces ischemic events but increases the risk of bleeding events. Yet, the role of aspirin in primary prevention of cardiovascular disease remains unclear. PURPOSE: To produce a clinically relevant benefit-risk assessment of aspirin for primary prevention of cardiovascular disease. METHODS: We performed a meta-analysis of aspirin effects in primary prevention of cardiovascular disease comprising 13 randomized-controlled trials in 164.225 patients comparing aspirin versus placebo/control during a mean follow-up period of 6.4 years. Using a random effect model, relative risks and 95% confidence intervals were calculated for each outcome. RESULTS: Aspirin reduced the relative risk of ischemic stroke by 10% (RR: 0.90; 95% CI: 0.82–0.99), myocardial infarction by 14% (RR: 0.86; 95% CI: 0.77–0.95) and the major adverse cardiovascular events by 9% (RR: 0.91; 95% CI: 0.86–0.95) but was associated with a 46% relative risk increase of major bleeding events (RR: 1.46; 95% CI: 1.30–1.64). Aspirin did not reduce the risk of cardiovascular mortality (RR: 0.99; 95% CI: 0.90–1.08), all-cause mortality (RR: 0.98; 95% CI: 0.93–1.02) or cancer (RR 1.05; 95% CI, 0.87–1.26). Aspirin use did not translate into a net clinical benefit adjusted for event-associated mortality risk (mean 0.034%; 95% CI: −0.18 to 0.25%).