In-hospital outcomes of ticagrelor versus clopidogrel in patients 75 years or older with acute coronary syndrome: findings from the Improving Care for Cardiovascular Disease in China (CCC)-Acute Coronary Syndrome Project

Background: The evidence for the comparative effectiveness and safety of ticagrelor versus clopidogrel in older patients with acute coronary syndrome (ACS) is limited, especially in the acute phase of ACS. This study aimed to compare the in-hospital outcomes of ticagrelor versus clopidogrel in older patients with ACS.Methods: Hospitalised ACS patients aged & GE;75 years who were recruited to the Improving Care for Cardiovascular Disease in China-ACS project between November 2014 and December 2019 and received aspirin and P2Y(12) receptor inhibitors within 24 h after first medical contact were included. The primary outcomes were in-hospital major adverse cardiovascular events (MACE) and major bleeding. Multivariable Cox regression was performed to evaluate the comparative effectiveness and safety of ticagrelor and clopidogrel. Inverse probability of treatment weighting (IPTW) and propensity score matching analyses were performed to evaluate the robustness of the results.Results: Of 18,244 ACS patients, 18.5% received ticagrelor. Multivariable-adjusted analysis revealed comparable risks of in-hospital MACE between patients receiving ticagrelor and clopidogrel (hazard ratio [HR] 1.12, 95% confidence interval [CI] 0.92-1.35). However, ticagrelor use was associated with 45% higher risk of in-hospital major bleeding compared with clopidogrel use (HR 1.45, 95% CI 1.09-1.91). Similar results were found in the IPTW analysis.Conclusions: ACS patients aged >= 75 years receiving ticagrelor during the acute phase had similar risk of in-hospital MACE, but higher risk of in-hospital major bleeding compared with those receiving clopidogrel. More evidence is needed to guide the use of P2Y(12) receptor inhibitors during hospitalisation in older patients with ACS.