Women who have migraines with aura may be more likely to have a stroke or heart attack than women who don't have the condition, and the association varies by migraine frequency, according to research published in the June 24, 2009, online issue of Neurology®, the medical journal of the American Academy of Neurology. An aura is a visual or other sensory disturbance that occurs before the migraine starts, such as seeing bright lights.

The study found that women with migraine with aura whose migraines occur at least once a week are more than four times as likely to have a stroke as women who do not have migraines. Women with migraine with aura who have migraines less than once a month were more than twice as likely to have a heart attack and nearly twice as likely to have had heart procedures such as coronary artery bypass surgery or angioplasty. In contrast, women who had migraines with aura once a month had no increased risk of stroke or heart problems.

"These results should be interpreted with caution, since the number of migraine and migraine features were self-reported and there were relatively low numbers of stroke and heart problems in the large study group," said study author and member of the American Academy of Neurology Tobias Kurth, MD, ScD, of Brigham and Women's Hospital, Harvard Medical School and INSERM, the French national research institute. "Nonetheless, more research is needed to determine how and why these differences occur and whether preventing migraines could reduce the risk of stroke and heart problems."

The Women's Health Study involved 27,798 U.S. women health professionals age 45 and older. The women had no heart or cerebrovascular problems at the start of the study and were followed for about 12 years. During that time, 706 women, or 2.5 percent of the group had cerebrovascular events, including 305 heart attacks and 310 strokes. In addition, 655 women had heart procedures such as bypass surgery.

Of the 3,568 women with migraine at the start of the study, 75 percent had migraines less than once a month, 20 percent had them once a month, and 5 percent had migraines at least once a week. A total of 1,428 had migraine with aura.

The study was supported by the National Heart, Lung, and Blood Institute, National Cancer Institute, Donald W. Reynolds Foundation, Leducq Foundation and Doris Duke Charitable Foundation.

The American Academy of Neurology, an association of more than 21,000 neurologists and neuroscience professionals, is dedicated to promoting the highest quality patient-centered neurologic care. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as multiple sclerosis, restless legs syndrome, Alzheimer's disease, narcolepsy, and stroke.

Source: American Academy of Neurology (AAN)