The American Heart Association and the American Stroke Association have together issues new guidelines on how to prevent strokes. The new guidelines constitute a thorough reevaluation of the scientific literature on stroke prevention, and contain many differences from the previous set of guidelines, which were published in 2006.
Among the key recommendations:
• Healthy lifestyle choice, such as not smoking, eating a low-fat diet high in fruits and vegetables, drinking in moderation, exercise regularly, and maintaining normal body weight, are additive and together can lower the risk of a first stroke by up to 80%.
• Emergency physicians should attempt to identify patients at high risk of smoke, and they consider making referrals, conducting screenings, or beginning preventive therapy.
• Genetic screening for stroke risk may be appropriate in some circumstances, depending on family history and other factors.
• The usefulness of carotid artery stenting or carotid endarterectomy for patients with asymptomatic carotid artery stenosis remains uncertain. The advantages of revascularization over medical therapy alone are not well established.
• The general population should not be screened for carotid artery stenosis.
• Low-dose aspirin does not prevent a first stroke in low-risk patients or those with diabetes or asymptomatic peripheral artery disease. Aspirin may be appropriate for patients whose risk of stroke is high enough to outweigh the risk of bleeding with aspirin.
While the recommendation discusses the use of warfarin and antithrombin prophylaxis in trial fibrillation, there’s no specific recommendation for the thrombin inhibitor dabigatran, which receive FDA approval on Oct. 19, after the guidelines had been finalized, raising the question of whether the new guidelines are already out of date.
Everything we do is out of date as soon as it’s done. Our guidelines aren’t based on whether a drug has been approved or not. They’re based on the science and on the evidence . . . If a new study or studies become available after a guideline has been published that affects our recommendation, then publish an intermediate practice advisory.
Director of Duke Stroke Center in Durham, N.C., noted that many questions remain. For example, it is unknown how often patients on dabigatran should have their liver function tested. If a patient has a bleeding complication while on the drug, there’s no way currently to reverse that. And there are suggestions that dabigatran might increase the risk of MI.
The bottom line is that having this is an option is a very good thing. We’ve had a single drug that’s been proved to be efficacious for decades, but it carries its own luggage. We’re just going to have to see how this fits into clinical practice.