The safety outcomes assessed were the incidence of ADRs, serious ADRs, and bleeding AEs. The incidence of bleeding AEs was also assessed by clinical characteristics. AEs were defined as any unfavorable or unintended sign (including an abnormal laboratory finding), symptom, or disease showing a temporal association with the use of the study drug, irrespective of whether it was considered to be related to the drug. ADRs were defined as AEs for which a relationship to prasugrel could not be ruled out. AEs or ADRs that satisfied the following criteria were classified as serious: an event which (1) results in death, (2) is life-threatening, (3) requires hospitalization or prolongation of hospitalization, (4) results in disability or significant incapacity, (5) has the potential to result in disability or significant incapacity, (6) is as serious as any of the outcomes listed above, or (7) causes a congenital anomaly or birth defect. Detailed definitions of bleeding and cardiovascular events are provided in Electronic Supplement 1. Regarding the incidence of bleeding AEs by clinical characteristics, we identified clinical characteristics potentially affecting the incidence of bleeding AEs by comparing patients with bleeding AEs with those without.