Comparison of efficacy and safety of a standard versus a loading dose of clopidogrel for acute myocardial infarction in patients ≥ 75 years of age (from the FAST-MI registry)

Abstract

Data are lacking on the efficacy and safety of a loading dose (LD) of clopidogrel in elderly patients with acute myocardial infarction (AMI). FAST-MI is a nationwide registry that was carried out over a 1-month period in 2005 and included consecutive patients with AMI admitted to intensive care units <48 hours from symptom onset in 223 participating centers. We assessed the impact of a clopidogrel LD (≥300 mg) compared to a conventional dose (<300 mg) on bleeding, need for blood transfusion, and 30-day and 12-month survivals in 791 elderly patients (≥75 years old, mean age 81 ± 4 years, 48% women, 35% with ST-segment elevation MI) included in this registry. Fifty-nine percent (466 patients) received a clopidogrel LD. Follow-up was >99% complete. Major bleeding and blood transfusions were not significantly different in patients who received a clopidogrel LD (3.2% vs 3.7%, p = 0.72; 5.4% vs 6.2%, p = 0.64, respectively). Early mortality was also not significantly different (10.1 vs 10.8, p = 0.76). Using multivariate analyses, clopidogrel LD did not significantly affect major bleeding or transfusion (odds ratio 1.03, 95% confidence interval 0.49 to 2.17, p = 0.94) and 12-month mortality (hazard ratio 1.00, 95% confidence interval 0.72 to 1.40, p = 0.98). In conclusion, the present data showed that in elderly patients admitted for AMI, use of a LD of clopidogrel compared to a conventional dose was not associated with increased in-hospital bleeding, need for transfusion, or mortality. Large-scale randomized trials are still needed to identify the optimal LD of clopidogrel for elderly patients admitted for AMI.