Preventing recurrence of ischemic stroke

Sept. 28 - Washington, D.C. - Contrary to conventional wisdom, heparin and warfarin are not effective in preventing recurrence of ischemic stroke, Dan Brewer, MD, associate professor of family medicine, University of Tennessee, Knoxville, told attendees at the AAFP Scientific Assembly.

Instead, clinicians are advised to use either aspirin or clopidogrel. "In other words, antiplatelet agents rather than oral anticoagulation are recommended to reduce the risk of recurrent stroke and other cardiovascular events," Brewer said.

Brewer noted that the combination of aspirin and extended-release dipyridamole is also considered an option by the National Institutes of Health, but is problematic. "Combining aspirin and extended-release dipyridamole may not be more effective than aspirin alone and is contraindicated in patients with CAD?especially those with stable angina," he said.

"I'm very nervous about giving aspirin and extended-release dipyridamole," said Brewer.

Are two anticoagulant drugs better than one alone? For the most part, the answer is No, according to Dr. Brewer. "The combination of aspirin and clopidogrel carries a risk of bleeding."

However, the combination might be beneficial if used in the short-term (4-6 weeks) immediately after stroke. An ongoing study will eventually provide evidence about this strategy, he reported.

There is no "clear cut winner" with regard to the comparative effectiveness of aspirin versus clopidogrel, said Dr. Brewer.

There is also consensus about the amount of aspirin to prescribe; the range is 75-300 milligrams a day. "Neurologists tend to think a higher dose is better. Cardiologists tend to say any dose in that range is okay as long as there is no bleeding," said Dr. Brewer.