BOSTON — Aspirin works just as well as Coumadin, the granddaddy of stroke drugs, in helping most patients avoid recurrent strokes, according to a study aimed at settling a long-standing question among doctors.
Many doctors suspected that Coumadin was more effective but that aspirin was safer. This study challenges both views, showing the two drugs are equals in both respects, said Dr. J.P. Mohr, a neurologist at Columbia-Presbyterian Medical Center in New York who led the research.
Both aspirin and Coumadin work by thinning the blood, warding off clots that can block blood vessels.
The study, published in Thursday's New England Journal of Medicine, looked at patients who had already suffered the most common kinds of strokes — those that happen when a clot that forms outside the heart obstructs the flow of oxygen-carrying blood to the brain.
However, Coumadin remains superior for some other patients. Earlier research has shown that the drug is more effective than aspirin in preventing additional strokes in patients whose first stroke stemmed from clots that formed inside the heart.
In the latest study, researchers tested the two drugs on 2,206 patients for two years at 48 hospitals around the country.
Almost 18 percent in the Coumadin group died or suffered another stroke, compared with 16 percent of those on aspirin. The difference was not considered statistically significant. Also, both drugs caused low rates of bleeding as a side effect.
The findings may actually give an edge to aspirin, because it is cheaper and demands less medical supervision, said Dr. William J. Powers, a brain researcher at Washington University in St. Louis who wrote an accompanying editorial.
Aspirin might cost about $10 for a year's worth of treatment. Coumadin and the necessary blood tests can together cost several hundred dollars.
Coumadin, known generically as warfarin, has been used for about 50 years to combat stroke. Aspirin's benefit for stroke patients was widely recognized about 30 years ago.
About 160,000 Americans die each year from strokes. Strokes are the nation's leading cause of serious, long-term disability.
The study was sponsored by the National Institutes of Health.