UW News

December 18, 2004

Stroke risk is greater for migraine sufferers, especially those on oral contraceptives

UW Health Sciences/UW Medicine

Migraine sufferers are twice as likely to experience a stroke, compared to people who do not get this type of headache. People whose migraines are accompanied by auras, such as scintillating lights or other visual disturbances, are at somewhat higher risk of a future stroke than are those whose migraines do not produce auras. In addition, female migraine sufferers who take oral contraceptives have eight times greater odds of a stroke than those not on birth control pills.

The findings appear in an online report published by the British Medical Journal.

The risk analysis came from a review conducted by a group of Canadian, Spanish, and United States scientists of 14 studies on the link between migraines and stroke. The review suggests that migraine may be an independent risk factor for stroke, according to Dr. Ali Samii, associate professor of neurology at the University of Washington (UW), who did the study along with Dr. Mayhar Etminan of Montreal’s Royal Victoria Hospital and with other collaborators from Spain. Samii practices at the Veterans Affairs Puget Sound Health Care System and UW Medical Center.

Migraine headaches are usually severely painful and throbbing. Before or during the headache, the sufferer may feel nauseated, vomit, and become irritated by light, noise, or odors. Because of this heightened sensitivity, many will seek a dark, quiet place during an attack.

The higher risk for stroke may be related to reduced blood flow in the brain during a migraine, but the exact mechanism for this association is unknown. The suspected link between migraine and stroke should be further investigated, the scientists said, as should the increased chance of stroke among women migraine sufferers who take birth control pills.