Risks of adverse events for users of proton-pump inhibitors plus aspirin or clopidogrel in patients with aspirin-related ulcer bleeding.

Background & aims Clopidogrel is widely prescribed for patients with of aspirin-related upper gastrointestinal bleeding (UGIB) history. This study aimed to compare the risk of a major adverse cardiovascular event (MACE), UGIB, and mortality between aspirin and clopidogrel in patients at risk of bleeding. Methods We analyzed adult patients at high risk of UGIB following aspirin-related bleeding for secondary MACE prevention between 2000 and 2012. Secondary prevention was for those patients who had ever been hospitalized for cardiovascular disease and reused aspirin or changed to clopidogrel after discharge. Study endpoints were recurrence of MACE, UGIB, and death in 90 days of follow-up. The associations between study outcomes and the use of clopidogrel (versus aspirin) were analyzed. Results Among 947 eligible patients, 653 reused aspirin (in combination with a proton-pump inhibitor [PPI]) and 294 were treated with clopidogrel (in combination with a PPI) after discharge for UGIB. Compared with aspirin treatment, clopidogrel showed an increased risk of MACE (adjusted hazard ratio [aHR] 1.65; 95% confidence interval [CI] 0.87-3.12), and UGIB (aHR 1.25; 95% CI 0.66-2.36), but without statistical significance in 90 days' follow-up. Clopidogrel use was associated with greater than four times the risk of any cause of mortality (aHR 4.84; 95% CI 1.59-14.75), but the significance did not hold in PSM cohort analysis (P = 0.06). Conclusions A non-significant difference between clopidogrel and aspirin for short-term MACE prevention as well as UGIB recurrence was found in the present study. Further research to assess 90-day mortality would assist clinical decision making.