Impact of Ezetimibe Coadministered With Statins on Cardiovascular Events Following Acute Coronary Syndrome: A 3-Year Population-Based Retrospective Cohort Study in Taiwan

Abstract

Background Conflicting results using the combination of ezetimibe and statins to reduce the risk of cardiovascular events in patients with acute coronary syndrome (ACS) have been reported. Objective The aim of this work was to assess the effectiveness of ezetimibe coadministered with statins in reducing cardiovascular events in patients with ACS. Methods A retrospective cohort study of patients discharged after hospitalization with ACS was conducted from January 1, 2006, to December 31, 2007, and included those who were prescribed statins alone (n = 37,753) and those who received ezetimibe plus statins (n = 1001) within 365 days after the hospitalization, based on patient data obtained from the National Health Insurance Research Database (NHIRD) in Taiwan. The propensity score method was used to identify a 1:1 matched cohort (n = 2002). Risk of rehospitalization for ACS was analyzed by a multivariable Cox proportional hazards regression model. Results The crude event rate of rehospitalization due to ACS in the original cohort was 13.4 per 100 person-years (268 events) in the combination group and 22.6 per 100 person-years (12,724 events) in the statins-alone group (adjusted hazard ratio [HR] 0.69; 95% CI, 0.62–0.78). The crude event rates of rehospitalization due to ACS in the matched cohort were 13.4 and 20.0 per 100 person-years in the combination group and statins-alone group, respectively (HR 0.62; 95% CI, 0.53–0.73). Compared with statins alone, the adjusted HRs for rehospitalization for percutaneous transluminal coronary angioplasty without stent, with stent, and revascularization for the combination group in the matched cohort were 0.61 (0.50–0.75), 0.62 (0.48–0.81), and 0.62 (0.51–0.76), respectively. Conclusions Based on the data of Taiwan's NHIRD, our findings suggest that patients with ACS on ezetimibe combined with statins had a significantly lower risk of rehospitalization due to ACS, percutaneous transluminal coronary angioplasty, and revascularization than those on statins alone. The generalization of the results is limited because of using claims data of a specific population as the data source.