(166) Effectiveness, Safety, and Mortality of Cilostazol versus Clopidogrel in East Asian Patients with Ischemic Stroke and Transient Ischemic Attack

Background: Cilostazol and clopidogrel are both widely used to prevent thrombotic events. However, there is limited evidence on the effectiveness of cilostazol in East Asian patients with ischemic stroke (IS) or transient ischemic attack (TIA). Unlike clopidogrel, cilostazol does not require activation through the CYP2C19 enzyme before platelet inhibition. Thus, cilostazol might be a reasonable alternative to clopidogrel, especially for East Asian patients who have a higher prevalence of CYP2C19 enzyme poor metabolizers compared to patients in Western countries.

Objectives: To compare the effectiveness, safety, and mortality of cilostazol and clopidogrel in East Asian patients with IS and TIA.

Methods: This retrospective cohort study utilized Taiwan’s Health and Welfare Database. We included patients who were hospitalized due to IS and TIA between 2009 and 2018 and discharged with either cilostazol or clopidogrel. Each patient should receive at least one aspirin prescription during hospitalization. Cilostazol users were in the exposure group and clopidogrel users were in the reference group. Propensity score matching was employed to balance covariates between the study groups. Effectiveness outcomes were the composite of IS, TIA, and acute myocardial infarction. Safety outcomes were the composite of intracranial hemorrhage and gastrointestinal bleeding; Mortality outcomes were all-cause mortality, cardiovascular mortality, and fatal stroke. Poisson regression models were used to estimate the incidence rate, and Cox-proportional hazard models were employed to compare the outcomes between the study groups.

Results: We included 1,084 cilostazol and 6,286 clopidogrel users, with 1,083 matched pairs after 1:1 propensity score matching. No significant differences were observed in the composite effectiveness outcome (HR: 1.05; 95% CI: 0.82-1.34), composite safety outcome (HR: 1.18; 95% CI: 0.70-2.00), all-cause mortality (HR: 0.99; 95% CI: 0.85-1.15), cardiovascular mortality (HR: 0.81; 95% CI: 0.59-1.11), and fatal stroke (HR: 0.53; 95% CI: 0.20-1.40) between the two groups.

Conclusions: Our study suggests comparable risks between cilostazol and clopidogrel users in East Asian IS and TIA patients. Cilostazol can be consider an alternative to clopidogrel in East Asian population.