Background: Aspirin offers modest reduction in stroke in patients with atrial fibrillation. Whether combination of aspirin with clopidogrel offers additional protection is unclear. Methods: Post-hoc subgroup analysis of 593 participants with a history of atrial fibrillation in the Clopidogrel for High Atherothrombotic Risk and Ischemic Stabilization, Management, and Avoidance (CHARISMA) randomized trial testing clopidogrel 75 mg per day plus aspirin (75–162 mg per day) vs. aspirin alone in patients with stable cardiovascular disease or multiple cardiovascular risk factors. Results: Mean patient age was 70 years, 78% were men, and hypertension, heart failure and diabetes were present in 78, 20 and 44%, respectively. During a median follow-up of 2.3 years, stroke (ischemic and hemorrhagic) occurred in 15 of 298 assigned to clopidogrel plus aspirin and in 14 of 285 given aspirin alone (hazard ratio, HR, 1.03, 95% CI 0.49–2.1). There was no difference in all-cause mortality (HR 1.1, 95% CI 0.6–1.9) or in the composite of stroke, myocardial infarction, or vascular death (HR = 1.2, 95% CI 0.7–2.0). Severe/fatal extracranial hemorrhage occurred in 6 patients with combination vs. 3 with aspirin alone. Conclusions: This post-hoc subgroup analysis does not support the use of this combination over aspirin alone in patients with a history of atrial fibrillation pending results of ongoing larger randomized trials.

Keywords:
Atrial fibrillation, Clopidogrel, Aspirin, Antiplatelet, Stroke
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© 2008 S. Karger AG, Basel
2008
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