TUESDAY, June 23, 2009 (HealthDay News) -- Women who've had migraines with auras have an increased risk of developing brain lesions, a new study has found.
Whether these small areas of damaged brain tissue affect function or cognition, however, remains unknown, the researchers added.
"Migraine used to be thought of as episodic, with no trace they'd occurred, but these data suggest that there may be tissue damage associated with migraine," said study author Lenore Launer, chief of neuroepidemiology at the U.S. National Institute on Aging.
"But, there are no known clinical implications from these findings," Launer added. "Our next step is to look at the functional significance of these lesions. They seem to be clinically silent for the most part, though it's possible they may be associated with some cognitive or motor impairment. It's something that needs to be investigated further."
The study, in the June 24 issue of the Journal of the American Medical Association, found that women who experience migraine with aura in middle age are twice as likely to have brain lesions late in life as those who never had migraines.
Migraine is a very common neurological disorder, according to the study. More than one in 10 adults and about one in 20 children have migraines, which are intense, periodic headaches. About a third of those who have migraines have what's known as an aura that precedes the migraine. Often the aura is a visual disturbance, such as flashing lights, but it can also be a physical feeling, such as dizziness or numbness. Recent research has found that migraine with aura is associated with an increased risk of stroke and coronary artery disease, according to background information in the study.
Launer and her colleagues followed a group of 4,689 male and female residents of Iceland starting in 1967, when they were middle-aged, and ending between 2002 and 2006, when all participants underwent brain MRIs.
They found "infarct-like" brain lesions in 39 percent of the men and 25 percent of the women.
The lesions were very small areas of brain tissue damage, Launer said -- some as small as a pinhead. The researchers don't know exactly what causes the lesions.
Migraine with aura was reported in 361 participants. Brain lesions were found in 23 percent of the women in this group, compared with 14.5 percent of women without headaches. After adjusting the data for age, sex and follow-up time, the researchers found that women who had migraine with aura had nearly twice the risk of developing brain lesions later in life.
No such association was found for men. Launer said this could be a chance finding because the study might not have included enough men with auras, or there could be something specific that occurs in women who have migraines with auras; the researchers just don't know.
"This study raises a lot of questions," said Dr. Bruce Silverman, a neurologist at Providence Hospital and Medical Center in Southfield, Mich. "I think these brain lesions definitely affect the function of the brain to some extent, and the more you have, the more chance it could be clinically relevant."
"If you suffer from migraine, it's important to seek attention and care for that," Silverman stressed. "It's not OK to just suffer in silence. You may be doing yourself greater harm and causing pathologic changes in the brain."
"Earlier treatment of migraine is important as a quality-of-life issue, but it may also have long-term benefit, maybe causing less of an anatomical effect," he said.
More information
The U.S. National Institute of Neurological Disorders and Stroke has more on migraines and other headaches.
