ADP‐induced platelet aggregation in acute ischemic stroke patients on aspirin therapy

BACKGROUND AND PURPOSE: Aspirin is an important therapeutic regimen to prevent the recurrent ischemic events or death after acute ischemic stroke. In this study, we evaluated the relationship between the extent of adenosine diphosphate (ADP)-induced platelet aggregation and outcome in acute ischemic stroke patients on aspirin therapy. METHODS: We selected 107 acute ischemic stroke patients who had been prescribed aspirin and evaluated platelet function test by using optic platelet aggregometer test after 5 days of taking it and investigated the prognosis 90 days after ischemic events. Kaplan-Meyer curve was used for survival analysis. RESULTS: After stratification of the subjected patients by tertiles of ADP-induced platelet aggregation, the events rates were 7.4%, 9.3% and 30.8% (P = 0.023). In multiple logistic regression analysis, old age over 70 years (OR, 13.7; 95% CI, 2.14-88.07; P = 0.001) and the increased ADP-induced platelet aggregation had independent significance to the risk of primary end-points after acute ischemic stroke (OR, 1.1; 95% CI 1.01 to 1.20; P = 0.026). CONCLUSIONS: This study showed that the increased ADP-induced platelet aggregation under using aspirin is associated with poor outcome after acute ischemic stroke.