Background: Previous studies showed inconsistent results in the effectiveness and safety of clopidogrel and aspirin in preventing ischemic stroke. Whether the use of clopidogrel in ischemic stroke patients would have a better effectiveness and safety profile than aspirin remains unknown.
Objectives: To compare the effectiveness and safety of clopidogrel versus aspirin use among acute ischemic stroke patients.
Methods: This retrospective cohort study with new user design was conducted using the Health and Welfare Database, which contains comprehensive healthcare services information of a nationally representative sample in Taiwan. Patients with aged 20 years or older who admitted to a hospital for a primary acute ischemic stroke between January 1, 2009 and December 31, 2018 were included. All patients were discharged with monotherapy clopidogrel or aspirin. Clopidogrel users were the exposure group and aspirin users were the reference group. Inverse probability of treatment weighting was applied to balance measured confounders between the two groups. Effectiveness outcomes were the composite major cardiovascular events, recurrent ischemic stroke, and acute myocardial infarction (AMI); Safety outcomes were the composite major bleeding events, intracranial hemorrhage (ICH), and major gastrointestinal (GI) bleeding. Cox proportional hazards regression models were used to compare the risk of each outcome between the two groups.
Results: A total of 71,101 acute ischemic stroke patients fully met the inclusion criteria. Among them, 5,731 received clopidogrel and 65,370 received aspirin. The mean follow-up time was 2.38 years for clopidogrel users and 2.43 years for aspirin users. Clopidogrel users were associated with lower risks of composite major bleeding events (Hazard ratio [HR]: 0.87; 95% CI: 0.83-0.92) and ICH (HR: 0.68; 95% CI: 0.61-0.75) compared to aspirin users. However, the risks of composite major cardiovascular events, recurrent ischemic stroke, AMI, and major GI bleeding were not significantly different between clopidogrel and aspirin users.
Conclusions: Our study supports the consideration of clopidogrel use as an effective alternative to aspirin for ischemic stroke patients. Clopidogrel had a lower major bleeding risk than aspirin. Clopidogrel could be a suitable choice for acute ischemic stroke patients.
.jpg "Hsin-Yi Huang, PhD, BCCCP (she/her/hers) photo")
