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Relation Between Aspirin Dose, All-Cause Mortality, and Bleeding in Patients With Recent Cerebrovascular or Coronary Ischemic Events (from the BRAVO Trial)

Published:September 17, 2008DOI:https://doi.org/10.1016/j.amjcard.2008.07.019
      Despite aspirin's established role in the treatment of atherosclerotic vascular disease, considerable controversy exists regarding its most effective dosing strategy. In a retrospective observational study, we examined the relation between prescribed aspirin dose (<162 mg vs ≥162 mg/day aspirin) and clinical outcome in 4,589 placebo-treated patients enrolled in the Blockage of the Glycoprotein IIb/IIIa Receptor to Avoid Vascular Occlusion (BRAVO) trial over a median follow-up of 366 days. Standard Cox regression analysis was employed because propensity analysis was not feasible. Compared with lower aspirin doses, higher doses were associated with lower unadjusted all-cause mortality (2.9 vs 1.6%, respectively; log rank chi-square 8.6, p = 0.0034). Higher aspirin dose remained independently predictive of lower all-cause mortality in a multivariable Cox proportional hazards model (hazard ratio 0.64, 95% confidence interval 0.42 to 0.97, p = 0.037). However, there was no significant difference in the incidence of the composite endpoint death, nonfatal myocardial infarction, or nonfatal stroke (6.1% vs 6.2%, p = 0.74). Higher aspirin dose was a significant independent predictor of any (hazard ratio 1.32, 95% confidence interval 1.12 to 1.55, p = 0.001) but not serious bleeding. In conclusion, our findings suggest that aspirin doses of ≥162 mg/day may be more beneficial than those <162 mg/day at preventing death.
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