Impact of Bleeding on Myocardial Infarction, Stroke, and Death During 12 Months Dual Antiplatelet Therapy After Acute Coronary Syndrome

Background: Bleeding remains a complication during dual antiplatelet therapy (DAPT) for acute coronary syndrome (ACS). Some data suggest a link between bleeding and worsened vascular outcomes. However, this association is unclear, due to omitting of minor bleedings when applying conservative scales. In contrast, the Platelet Inhibition and Outcomes (PLATO) trial classification used broad realistic capturing of all bleedings.

Methods: Access was gained to the Food and Drug Administration-issued adjudication data set on which post hoc analyses of bleeding, myocardial infarction (MI), stroke, and death were conducted. Bleeding was defined as minimal, minor, major, and life-threatening or fatal (LTOF) as per the original PLATO scale.

Results: Among 18,624 enrollees, 10,705 adjudicated events occurred across 7171 patients. There were 618 minimal, 1412 minor, 1216 major, and 536 LTOF bleedings for the total of 3782 events reported in 3387 patients. There were 938 deaths, 2751 MIs and 359 strokes. The overall bleeding was 20.3%, exhibited in 19.2% patients. Total bleeds were associated with less deaths (odds ratio [OR]: 0.55, 95% confidence interval [CI]: 0.47-0.63) and MI (OR: 0.47, 95% CI: 0.41-0.54; P < .001 for both). There were no differences in deaths (OR: 1.11, 95% CI: 0.93-1.34; P = .24), but less MIs (OR: 0.72. 95% CI: 0.59-0.86; P < .001), and more strokes (OR: 2.17, 95% CI: 1.64-2.88; P < .001) after LTOF. Major, minor, and minimal bleeds were associated with less deaths and MI but not strokes.

Conclusion: These large uniformly adjudicated data reveal that within 12 months of dual antiplatelet therapy, 1 out of 5 patients experiences bleeding. Overall, bleeding was associated with diminished incidence of death and MI but not strokes.