June 29, 2009

Midlife Migraines Linked to Lesions

Middle-aged women who experienced migraine headaches with aura (sensory disturbances affecting vision, balance or speech) had a higher prevalence of cerebellar brain lesions when they were older, according to a recent study published in the Journal of the American Medical Association.

Migraine is a common neurovascular disorder that affects approximately 11 percent of adults and is more common in women than in men. Approximately one-third of individuals with migraine experience neurological aura symptoms before the onset of their headache. Although migraine is considered to be an episodic condition with no long-term consequences, recent studies suggest that migraine attacks may be associated with brain lesions identified on magnetic resonance imaging (MRI) in later life.

Ann I. Scher, Ph.D., of Uniformed Services University, Bethesda, Md., and colleagues examined the relationship of midlife migraine symptoms and late-life infarct (tissue death)-like lesions evident on MRI. The study included 4,689 men and women in Reykjavik, Iceland, born between 1907 and 1935. Fifty-seven percent were women. Study participants were followed-up since 1967, examined, and interviewed about migraine symptoms in midlife.

Between 2002 and 2006, more than 26 years later, researchers performed comprehensive cardiovascular risk assessment and brain MRIs. Infarct-like lesions were present on MRI in 39.3 percent of men and 24.6 percent of women. After adjusting for age, sex, and follow-up time, participants with midlife migraine with aura were found to be at increased risk for infarct-like lesions.

The relationship between migraine with aura and cerebellar infarcts was only significant in women. Lesions in the cerebellum, but not in other locations of the brain, were more prevalent in women with migraine with aura, compared to women without headache (23 percent vs. 15 percent). There was no difference in prevalence for men (19 percent vs. 21 percent). The clinical significance of the infarct-like lesions, such as whether the individuals with them had any symptoms, was not assessed.

Tobias Kurth, MD, Sc.D., of the University Pierre et Marie Curie, Paris, and Christophe Tzourio, M.D., Ph.D., of the University Pierre et Marie Curie and Harvard School of Public Health, Boston, write in an accompanying editorial that the clinical implications of this study ". . .should be interpreted with caution."

They continue, "In the absence of the source and the nature of infarct-like lesions and the absence of clinical symptoms or consequences, it is premature to conclude that migraine has hazardous effects on the brain. In this regard, brain scans among patients with migraine should not be initiated to detect silent brain lesions but to rule out rare secondary forms of migraine among those patients with atypical migraine forms or migraine courses."

SOURCE: JAMA, June 24, 2009