P4011Efficacy and safety of perioperative aspirin therapy in non-cardiac surgery: a systematic review and comprehensive meta-analysis of randomized controlled trials

Abstract

Background: Aspirin is a key element of prevention therapy in cardiovascular disease (CVD) and thromboembolism. In the setting of non-cardiac surgery however, continuation of aspirin therapy remains questionable, with clinical trials providing inconclusive evidence about cardiovascular benefits in comparison to bleeding risks. Purpose and methods: To assess the value of aspirin therapy in this setting, we performed a systematic review and comprehensive meta-analysis of all available randomized controlled clinical trials (RCTs) on aspirin vs. no aspirin therapy in non-cardiac surgery. Seven RCTs involving 28,302 patients were included, and perioperative clinical outcomes of all-cause mortality, cardiovascular events, thromboembolism and major bleeding were separately evaluated. Results: All-cause mortality was not significantly different in aspirin vs. no aspirin groups (3.7% vs. 3.8%; odds ratio (OR) 0.97, 95% confidence interval (CI) 0.86- 1.10). The same was true for cardiovascular mortality (2.0 (aspirin) vs. 2.1% (no aspirin)), myocardial infarction (2.5% (aspirin) vs. 2.5% (no aspirin)), cerebrovascular events (0.6% (aspirin) vs. 0.6% (no aspirin)) and peripheral arterial events (0.2% (aspirin) vs. 0.3% (no aspirin)). Aspirin significantly reduced the risk for venous thromboembolic events (1.5% (aspirin) vs. 2.0% (no aspirin); OR 0.74 with CI 0.59-0.94. Perioperative major bleeding was significantly more frequent in aspirin groups (4.4% vs. 3.7%; OR 1.18 with CI 1.05-1.33, p=0.007). Aspirin's number needed to harm through major bleeding was lower (161) than its number needed to treat for prevention of thromboembolism (185). Conclusion: The present analysis found no influence of aspirin therapy on survival and cardiovascular events, and a benefit in prevention of thromboembolism came at the expense of major bleedings. The available data do currently not support a routine perioperative continuation of long-term aspirin therapy in CVD patients. Identification of cardiovascular high-risk patients possibly profiting from aspirin continuation remains challenging and needs to be further evaluated in clinical trials.