Comparative effectiveness and safety of ticagrelor and clopidogrel in patients with or without chronic liver disease: a nationwide cohort study

Background Although the effectiveness and safety of ticagrelor versus clopidogrel may differ in patients with chronic liver disease, there is a scarcity of evidence comparing ticagrelor and clopidogrel in patients with chronic liver disease. We aimed to evaluate the risk of major adverse cardiovascular events (MACE) and major bleeding associated with ticagrelor versus clopidogrel in patients undergoing percutaneous coronary intervention (PCI) due to acute coronary syndrome by chronic liver disease status. Methods Using the Korean healthcare database, we included adult patients who underwent PCI and initiated ticagrelor or clopidogrel treatment within 7 days of an acute coronary syndrome diagnosis. Patients were divided into two mutually exclusive groups: patients with chronic liver disease and patients without chronic liver disease. Within each group, the hazard ratios (HRs) with 95% confidence intervals (CIs) of MACE and major bleeding associated with ticagrelor versus clopidogrel were calculated using a Cox proportional hazards model within a 1:1 propensity score (PS) matched cohort. Results The final cohort included 14,261 and 148,535 patients with and without chronic liver disease, respectively. After PS matching, the risk of MACE (with chronic liver disease, HR: 1.01, 95% CI: 0.91-1.13; without chronic liver disease, HR: 1.02, 95% CI: 0.98-1.05; P for homogeneity: 0.865) and major bleeding (with chronic liver disease, HR: 1.07, 95% CI: 0.71-1.61; without chronic liver disease, HR: 1.32, 95% CI: 1.15-1.53; P for homogeneity: 0.342) for ticagrelor versus clopidogrel do not vary with chronic liver disease status. Conclusions Among acute coronary syndrome patients undergoing PCI, the use of ticagrelor versus clopidogrel was associated with a similar risk of MACE and an increased risk of major bleeding, but these risks did not vary with chronic liver disease status.