Efficacy and safety of fondaparinux in patients with ST-segment elevation myocardial infarction across the age spectrum. Results from the Organization for the Assessment of Strategies for Ischemic Syndromes 6 (OASIS-6) trial

AIMS: The OASIS-6 trial demonstrated the benefit of fondaparinux in patients with ST-segment elevation myocardial infarction (STEMI) not undergoing primary percutaneous coronary intervention. Elderly compared to younger patients are at higher risk of bleeding and could have a different balance of benefits and risks when treated with antithrombotic therapy. METHODS AND RESULTS: We explored the efficacy and safety of fondaparinux compared to control according to age tertiles in 12,092 patients with STEMI in the OASIS-6 trial. Death or myocardial infarction rates were reduced by fondaparinux in tertile I (age <56 years, 4.5% vs 4.8%, hazard ratio [HR] 0.94, 95% CI 0.71-1.25), in tertile II (age 56-68 years, 7.9% vs 9.7%, HR 0.80, 0.65-0.98), and in tertile III (age ≥69 years, 17.2% vs 19.8%, HR 0.87, 95% CI 0.75-1.01, P for heterogeneity = 0.87). Severe hemorrhage rates were reduced in tertile I (0.5% vs 0.6%, HR 0.94, 95% CI 0.41-2.12), in tertile II (0.9% vs 1.5%, HR 0.63, 95% CI 0.35-1.11), and in tertile III (2.1% vs 2.4%, HR 0.86, 95% CI 0.56-1.33, P for heterogeneity = 0.86). Death, myocardial infarction, or severe hemorrhage rates were reduced in tertile I (4.8% vs 5.0%, HR 0.95, 95% CI 0.72-1.25), in tertile II (8.1% vs 10.1%, HR 0.79, 95% CI 0.65-0.97), and in tertile III (17.6% vs 20.4%, HR 0.86, 95% CI 0.74-1.00, P for heterogeneity = 0.77). CONCLUSION: The balance of benefits and risks of fondaparinux is consistent across age tertiles, supporting its use across the age spectrum of patients with STEMI who do not undergo primary percutaneous coronary intervention