One-year incidence and clinical impact of bleeding events in patients treated with prasugrel or clopidogrel after ST-segment elevation myocardial infarction.

BACKGROUND: Little information is available on the long-term incidence of bleeding events after ST-segment elevation myocardial infarction (STEMI) with the current antithrombotic strategy.

AIMS: To evaluate the effect of bleedings for up to 12months on clinical events and therapeutic compliance in unselected STEMI patients treated with prasugrel or clopidogrel.

METHODS: Patients were treated with clopidogrel or prasugrel according to guidelines. The primary endpoint was first occurrence of a bleeding event from hospital discharge to 12months, assessed by the Bleeding Academic Research Consortium (BARC) classification using a dedicated questionnaire. Topography of bleedings, causes of premature cessation and ischaemic events were compared between clopidogrel- and prasugrel-treated patients.

RESULTS: A total of 390 patients were enrolled (211 in the prasugrel group, 179 in the clopidogrel group). Elderly, female and low-body weight patients were more likely to receive clopidogrel. At 12months, the incidence of major bleedings (BARC 3) was lower with prasugrel (1% vs 6%; P=0.02), mainly due to fewer transfusions. Elderly age was a risk factor for severe bleeding. Premature treatment cessation was related to ischaemic complications (P=0.03), and occurred more frequently with prasugrel (P=0.001). One-year mortality was very low (1.9 per 100 person-years, 95% confidence interval 0.9-4.0), and was higher in the clopidogrel group (P=0.03).

CONCLUSIONS: In this unselected STEMI population, the rate of major bleedings with prasugrel at 12months was low, but nuisance bleedings were frequent and led to more premature cessations than with clopidogrel. Prevention of bleeding complications, even minor, is necessary to prevent disruption of antithrombotic medication.