"It is a very important finding. Aspirin use in heart failure was a concern, but we didn’t see that," he said at the meeting, which was sponsored by the American Heart Association.
WARCEF enrolled patients at 176 centers in 11 countries between 2002 and January 2010, with more than a third of the patients enrolled in the United States. The study was funded by the National Institute of Neurological Disorders and Stroke.
The study also featured an unusual design, in that it was completely double-blinded even though half the patients received warfarin and half did not. To maintain the blind, all patients regularly went to warfarin clinics where their blood was drawn and INR reports generated that their physicians then used to adjust their warfarin dosages, even for the patients who received dummy warfarin pills.
"Neither patients nor their physicians knew who was on warfarin and who was on aspirin, so this gives us great confidence about the study results. It removes the possibility that one group received more intensive care," Dr. Thompson said.
WARCEF was sponsored by the National Institute of Neurological Disorders and Stroke. Dr. Homma and Dr. Thompson said that they had no disclosures.