Aspirin Beats Coumadin for Brain Blockage
Despite Treatment, Brain Artery Narrowing Still Deadly
March 30, 2005 -- Aspirin is safer and no less effective than Coumadin for treating dangerously blocked brain arteries, a major new study shows.
That's both good news and bad news. The good news is that many patients with blocked brain arteries may be able to avoid the expense and complications of treatment with Coumadin (also known by its generic name, warfarin). The bad news is that despite treatment, more than one in five patients suffers stroke, brain hemorrhage, or death within two years.
Brain artery narrowing -- what doctors call intracranial arterial stenosis -- happens when fatty deposits build up in the blood vessels of the brain, reducing blood flow. It causes about one in 10 strokes and transient ischemic attacks (TIAs), also known as ministrokes.
At least half of U.S. doctors treat this condition with the powerful blood thinner Coumadin, says Emory University neurologist Marc Chimowitz, MD. Chimowitz led a major study to find out whether Coumadin really works better than high-dose aspirin for patients with brain artery blockage. The findings appear in the March 31 issue of The New England Journal of Medicine.
Aspirin vs. Coumadin for Brain Blockage: Doctors Still Disagree
After enrolling 569 of a planned 800 patients, the study was stopped early by the federal agency overseeing the trial. Why? Patients getting Coumadin had higher rates of major bleeding and higher rates of death than patients taking aspirin.
"Aspirin, rather than [Coumadin], should be used to treat intracranial arterial stenosis," Chimowitz and colleagues write. "Using aspirin rather than [Coumadin] in these patients will substantially lower the risk of major hemorrhage and eliminate the inconvenience of using warfarin."
"If only the practice of medicine was so simple," writes Walter J. Koroshetz, MD, of Massachusetts General Hospital in Boston. Koroshetz's editorial accompanies the Chimowitz study.
Koroshetz notes that about 22% of all patients in the Chimowitz study suffered stroke or death --regardless of whether they got aspirin or Coumadin.
He notes that fewer than two-thirds of the study subjects achieved the desired level of blood-thinning effect from Coumadin treatment. While that's better than most doctors see in private practice, it is not good enough to get maximum benefit from Coumadin. More aggressive patient monitoring and blood-thinning treatment -- especially in the months soon after diagnosis -- might improve outcomes, Koroshetz suggests.
Both Chimowitz and Koroshetz suggest that an operation to widen narrowed brain blood vessels -- intracranial angioplasty -- might be a good idea in these patients. Chimowitz hopes to begin a clinical trial of brain angioplasty with stents -- a metal tube to keep brain-blood vessels open.
Chimowitz warns that the study findings do not apply to Coumadin when it is used to treat other conditions. He warns all patients on Coumadin not to stop taking their medication without talking with their doctors.