Aims: In the setting of percutaneous coronary intervention (PCI), due to a paucity of data, the optimal dose of aspirin is uncertain. We evaluated the safety of different doses of aspirin after PCI.
Methods and results: In the PCI-CURE study, 2658 patients with acute coronary syndromes undergoing PCI were stratified into three aspirin dose groups >/=200 mg (high, n = 1064), 101-199 mg (moderate, n = 538), and </=100 mg (low, n = 1056). For efficacy, the moderate- (7.4%) and high-dose groups (8.6%) had similar rates of cardiovascular death, myocardial infarction, or stroke compared with the low-dose group (7.1%). For safety, major bleeding was increased with high-dose aspirin [3.9, 1.5, and 1.9% in the high-, moderate-, and low-dose groups; hazard ratio (HR) of high vs. low dose 2.05 (95% CI 1.20-3.50, P = 0.009]. The net adverse clinical events (death, MI, stroke, major bleeding) favoured low-over high-dose aspirin (8.4 vs. 11.0%, HR 1.31, 95% CI 1.00-1.73 P = 0.056).
Conclusion: In this large observational analysis of patients undergoing PCI, low-dose aspirin appeared to be as effective as higher doses in preventing ischaemic events but was also associated with a lower rate of major bleeding and an improved net efficacy to safety balance.