Efficacy and safety of clopidogrel and aspirin do not differ in patients with stable ischemic stroke

Background: The current study compared the efficacy and safety of clopidogrel vs aspirin in the secondary prevention of ischemic stroke (IS). Methods: We included patients from the Taiwan National Health Insurance Research Database who were aged between 20 and 80 years, had their first ever IS, had no diagnosis of atrial fibrillation, and had not used an oral anticoagulant before the index IS between 2002 and 2010. We excluded patients who died or were admitted to a hospital due to acute myocardial infarction, recurrent IS, or major bleeding within 3 months of IS. Patients were then classified into clopidogrel as aspirin users. Propensity score matching was adopted to select clopidogrel and aspirin groups with similar baseline characteristics (n = 8457 vs 16,914, mean follow-up period of 2.1 years and 1.9 years, respectively). Conditional Cox proportional hazard regression was used to compare risks of all-cause death, cardiovascular death, recurrent stroke, acute myocardial infarction, and major bleeding in clopidogrel users and aspirin users. Results: The risks of all-cause death, cardiovascular death, recurrent stroke, and acute myocardial infarction did not differ between clopidogrel and aspirin users. Subgroup analyses revealed that the results were consistent regardless of age, disease severity, or comorbidity. Conclusion: According to real-world data, the efficacy and safety of clopidogrel and aspirin for secondary prevention of stable IS did not differ.