DRUG NEWS: STROKE PREVENTION
New research shows that aspirin is safer than warfarin and just as effective at preventing stroke and vascular death in patients with symptomatic stenosis of a major intracranial artery. Researchers stopped the study early due to concerns for the safety of patients taking warfarin.
The study involved 569 patients with symptomatic intracranial arterial stenosis. All patients had a greater than 50% stenosis of a major intracranial artery. They'd also all had a transient ischemic attack or nondisabling stroke within 90 days of enrolling in the study.
Researchers randomly assigned patients to receive either warfarin (target international normalized ratio [INR], 2 to 3) or 1,300 mg of aspirin daily. During an average follow-up period of 1.8 years, the rate of death, major hemorrhage, myocardial infarction, and sudden death were significantly higher among patients taking warfarin compared with those in the aspirin group. The rate of death from vascular causes was 5.9% in the warfarin group, compared with 3.2% in the aspirin group. The rate of death from nonvascular causes was also significantly higher in the warfarin group: 3.8% for those taking warfarin versus 1.1% for those taking aspirin.
In The New England Journal of Medicine, the researchers concluded that their findings don't support the common practice of administering warfarin rather than aspirin for symptomatic intracranial arterial stenosis. An accompanying editorial acknowledged their findings but noted that the aspirin dosage was unusually high and that the time patients taking warfarin spent in the INR target range was inadequate. The editorial called for more studies with carefully regulated anticoagulation.
Comparison of warfarin and aspirin for symptomatic intracranial arterial stenosis, The New England Journal of Medicine
, MI Chimowitz, et al., March 31, 2005; Warfarin, aspirin, and intracranial vascular disease, The New England Journal of Medicine
, WJ Koroshetz, March 31, 2005.