What is the effect of aspirin and APT on stroke prevention compared to placebo or control?
A meta-analysis of 8 trials of 4,876 subjects found a 22% (95% CI, 6-35) relative risk reduction in stroke with APT compared to placebo or control. The Stroke Prevention in AF (SPAF-I) study found a decrease in risk of stroke from 6.3% per year in placebo subjects to 3.6% per year, but a meta-analysis of 7 trials of 3,990 subjects found no significant benefit. Aspirin also showed no benefit in the elderly, or in preventing severe strokes. The Atrial Fibrillation Clopidogrel Trial With Irbesartan for Prevention of Vascular Events (ACTIVE-A) trial found a decrease in risk of stroke with dual antiplatelet therapy (DAPT), but the major bleeding rates with aspirin-clopidogrel were comparable to rates seen with warfarin (approximately 2% per year).