Effect of enoxaparin versus unfractionated heparin in diabetic patients with ST-elevation myocardial infarction in the Enoxaparin and Thrombolysis Reperfusion for Acute Myocardial Infarction Treatment-Thrombolysis In Myocardial Infarction study 25 (ExTRACT-TIMI 25) trial.

BACKGROUND: Patients with diabetes mellitus (DM) are at higher risk for complications after ST-elevation myocardial infarction (STEMI) than patients without DM. Potent antithrombotic therapies may offer particular benefit for these high-risk patients and must be balanced against the potential for increased bleeding.

METHODS: We performed a prospectively planned analysis of efficacy and safety in patients with DM among 20,479 patients with STEMI treated with fibrinolysis and randomized to a strategy of enoxaparin (up to 8 days) or unfractionated heparin (UFH) (48 hours) in ExTRACT-TIMI 25.

RESULTS: Patients with DM (n = 3060) were older and more likely to be women and to present with heart failure (P < .0001 for each) than those without DM. After adjustment for the TIMI Risk Score, sex, and renal function, patients with DM were at 30% higher risk for death or myocardial infarction (MI) by 30 days (OR(adj) 1.29, 95% CI 1.14-1.46). Among patients with DM, the enoxaparin strategy reduced mortality (9.5% vs 11.8%, relative risk [RR] 0.81, 95% CI 0.66-0.99), death/MI (13.6% vs 17.1%, RR 0.80; 95% CI 0.67-0.94), and death/MI/urgent revascularization (16.0% vs 19.7%, RR 0.81, 95% CI 0.70-0.94). The enoxaparin strategy was associated with a trend toward higher major bleeding (2.6% vs 1.6%, RR 1.63, 95% CI 0.99-2.69). Taking efficacy and safety into account, the enoxaparin strategy offered superior net clinical benefit (death/MI/major bleed, 14.8% vs 18.0%, RR 0.83, 95% CI 0.70-0.97) compared with UFH in patients with DM.

CONCLUSIONS: In a subgroup analysis, a reperfusion strategy including enoxaparin significantly improved outcomes compared with UFH among high-risk STEMI patients with DM undergoing fibrinolysis.