An updated guideline from the American Academy of Neurology recommends that people with nonvalvular atrial fibrillation, or irregular heartbeat, take oral anticoagulants, a type of blood thinner pill, to prevent stroke. The guideline is published in Neurology®, the medical journal of the American Academy of Neurology. The World Stroke Organization has endorsed the updated guideline.

Taking anticoagulants is especially important for people who have already had a stroke or a transient ischemic attack, which is a threatened stroke.

Irregular heartbeat is a major risk factor for stroke. "The World Health Organization has determined that atrial fibrillation is nearing epidemic proportions, affecting 0.5 percent of the population worldwide," said guideline lead author Antonio Culebras, MD, of SUNY Upstate Medical University in Syracuse, NY, and a Fellow of the American Academy of Neurology.

The uneven heart rhythm allows blood to remain in the heart's upper chambers. The blood can then form clots. These may escape the heart and travel to the brain, causing a stroke. About one in 20 people with untreated atrial fibrillation will likely have a stroke in the next year. Anticoagulants are highly effective in preventing stroke, but they also carry a risk of bleeding. They should be used only under close medical supervision.

Several new anticoagulant pills have been developed since the AAN's last guideline on this topic, which was published in 1998. The current guideline determined that the new anticoagulant pills, such as dabigatran, rivaroxaban and apixaban, are at least as effective, if not more effective than, the established treatment of warfarin and have a lower risk of bleeding in the brain. In addition, the new drugs have the added convenience of not requiring the frequent blood testing that warfarin requires.

The guideline also extends the value of this type of blood thinner to many people who are generally undertreated - such as the elderly, those with mild dementia, and those at moderate risk of falls - and whose health status was long thought to be a barrier to use.

"Of course, doctors will need to consider the individual patient's situation in making a decision whether or not to use anticoagulants, and which one to use, as the risks and benefits can vary for each person," said Culebras.

Culebras also noted that the guideline addresses special circumstances that may pertain to developing countries where new anticoagulant pills are not available or not affordable.

To learn more about stroke, please visit www.aan.com/patients.