P668Aspirin for primary prevention of cardiovascular disease

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%). Forest plot of major outcomes. Conclusions Aspirin use in primary prevention is associated with a reduced risk of stroke and myocardial infarction, but at a cost of an increased risk of major bleeding. Acknowledgement/Funding None