Adequate Platelet Function Inhibition Confirmed by Two Inductive Agents Predicts Lower Recurrence of Ischemic Stroke/Transient Ischemic Attack

BACKGROUND: The correlation between platelet function and recurrent ischemic stroke or TIA remains uncertain. OBJECTIVE: To investigate two inductive agents to detect platelet functions and assess associations with recurrent ischemic stroke/TIA. METHOD: The study included 738 ischemic stroke/TIA patients. On days 0, 3, and 9 after antiplatelet therapy, platelet function tests were determined by maximum aggregation rate (MAR) using a PL-11 platelet function analyzer and phase matching reagents. Two induction agents were used: arachidonic acid (AA) and adenosine diphosphate (ADP). At 3-month follow-up, recurrence of stroke/TIA was recorded. RESULT: Cut-off values of adequate platelet function inhibition were MAR(ADP) < 35% and MAR(AA) < 35%. Data showed that antiplatelet therapy could reduce the maximum aggregation rate. More importantly, adequate platelet function inhibition of either MAR(ADP) or MAR(AA) was not associated with the recurrence of stroke/TIA, but adequate platelet function inhibition of not only MAR(ADP) but also MAR(AA) predicts lower recurrence (0/121 (0.00%) versus 18/459 (3.92%), P = 0.0188). CONCLUSION: The platelet function tested by PL-11 demonstrated that adequate inhibition of both MAR(ADP) and MAR(AA) could predict lower risk of ischemic stroke/TIA recurrence.