Adherence to Aspirin in Secondary Prevention of Ischemic Stroke

OBJECTIVE: Compliance with antiplatelet therapy is essential for the efficiency of secondary prevention of ischemic stroke. The objective of this study was to evaluate adherence to aspirin treatment in patients with ischemic stroke. PATIENTS AND METHODS: We studied outpatients of 5 neurological ambulatory centers in an urban city, Valencia, all with a history of ischemic stroke who had received aspirin for at least 6 months. A personal interview was carried out in all cases, during which the patients were questioned about adherence to treatment. Platelet thromboxane A2 synthesis was assessed in a single laboratory for the biochemical determination in all patients. RESULTS: A total of 73 patients (mean age 67) were studied, with a mean duration of aspirin therapy of 25.4 months (range 6-144 months). Sixty-six patients (90.4%) were included in laboratory tests. All showed inhibition of thromboxane A2 synthesis, consistent with adherence to treatment. CONCLUSIONS: Aspirin compliance was found to be excellent. All the patients who presented themselves for laboratory tests were taking aspirin. Even if the patients who failed to show up for laboratory testing are regarded as noncompliants, at least 90% of all patients were compliants--in agreement with the findings of the recent literature. Personal interview plus biochemical determination of platelet thromboxane A2 synthesis seem adequate for assessing adherence to aspirin.