Aspirin and Ticlopidine for Prevention of Recurrent Stroke in Black Patients<SUBTITLE>A Randomized Trial</SUBTITLE>

Abstract

CONTEXT: Blacks are disproportionately affected by stroke, and they are about 2 times more likely than most other individuals in the United States to die of or experience stroke. OBJECTIVE: To determine the efficacy and safety of aspirin and ticlopidine to prevent recurrent stroke in black patients. DESIGN, SETTING, AND PATIENTS: Randomized, double-blind, investigator-initiated, multicenter trial of 1809 black men and women who recently had a noncardioembolic ischemic stroke and who were recruited between December 1992 and October 2001 from 62 academic and community hospitals in the United States and followed up for up to 2 years. INTERVENTION: A total of 902 patients received 500 mg/d of ticlopidine and 907 received 650 mg/d of aspirin. MAIN OUTCOME MEASURES: Recurrent stroke, myocardial infarction, or vascular death was the composite primary end point (according to intention-to-treat analysis). The secondary outcome was fatal or nonfatal stroke. RESULTS: The blinded phase of the study was halted after about 6.5 years when futility analyses revealed a less than 1% probability of ticlopidine being shown superior to aspirin in the prevention of the primary outcome end point. The primary outcome of recurrent stroke, myocardial infarction, or vascular death was reached by 133 (14.7%) of 902 patients assigned to ticlopidine and 112 (12.3%) of 907 patients assigned to aspirin (hazard ratio, 1.22; 95% confidence interval, 0.94-1.57). Kaplan-Meier curves for time to event for the primary outcome did not differ significantly (P =.12 by log-rank test). Kaplan-Meier curves for time to the secondary outcome of fatal or nonfatal stroke approached a statistically significant reduction favoring aspirin over ticlopidine (P =.08 by log-rank test). The frequency of laboratory-determined serious neutropenia was 3.4% for patients receiving ticlopdine vs 2.2% for patients receiving aspirin (P =.12) and 0.3% vs 0.2% for thrombocytopenia, respectively (P =.69). One ticlopidine-treated patient developed thrombocytopenia, which was thought to be a case of possible thrombotic thrombocytopenia purpura, and recovered after therapy with plasmapheresis. CONCLUSIONS: During a 2-year follow-up, we found no statistically significant difference between ticlopidine and aspirin in the prevention of recurrent stroke, myocardial infarction, or vascular death. However, there was a nonsignificant trend for reduction of fatal or nonfatal stroke among those in the aspirin group. Based on these data and the risk of serious adverse events with ticlopidine, we regard aspirin as a better treatment for aspirin-tolerant black patients with noncardioembolic ischemic stroke.