Antiplatelet agents for the secondary prevention of ischaemic stroke in patients with or without renal dysfunction

Background and purpose: Studies on using antiplatelet agents for secondary prevention in ischaemic stroke patients with renal dysfunction are limited. The Taiwan Stroke Registry database was used to compare the efficacy of antiplatelet agents. Methods: From the Taiwan Stroke Registry data, 39 174 acute ischaemic stroke patients were identified and were classified into three groups by antiplatelet agent: aspirin, clopidogrel and dual antiplatelet therapy (DAPT) with a combination of aspirin and clopidogrel. The re-stroke incidence and 1-year mortality were stratified by estimated glomerular filtration rate (eGFR) levels at admission: ≥90, 60–89 and <60 ml/min/1.73 m² or on dialysis. Results: Compared to the aspirin group, the re-stroke differences were not statistically significant for the clopidogrel group [adjusted subhazard ratio 0.95, 95% confidence interval (CI) 0.84–1.08] and the DAPT group (adjusted subhazard ratio 1.03, 95% CI 0.77–1.39) after controlling for the competing risk of death. The mortality rate increased as the eGFR level declined. In addition, compared to patients taking aspirin, there was no statistically significant difference in overall 1-year mortality for the clopidogrel group (adjusted hazard ratio 1.11, 95% CI 0.95–1.29) and for the DAPT group (adjusted hazard ratio 1.01, 95% CI 0.67–1.54). The results were consistent in different subgroups stratified by eGFR levels. Conclusions: There was no difference in the risks of recurrent stroke and 1-year mortality amongst ischaemic stroke patients with or without renal dysfunction receiving antiplatelet agents with aspirin, clopidogrel or dual agents with a combination of aspirin and clopidogrel, regardless of their renal dysfunction status.