Migraines Associated With Brain Lesions in Women
Brain lesions are more likely to be associated with migraine, but may not cause significant damage.
-- by Nina Lincoff
As if getting a migraine isn’t bad enough, there’s an additional worry of long-term effects on the brain, particularly for women. Migraine, a disorder that manifests itself as repeated severe headaches, usually on one side of the head, affects 15 percent of the general population. Migraine is three times more common in women than in men.
In the most recent issue of the Journal of the American Medical Association, a team of researchers from the Netherlands examined the change of white matter hyperintensities in a nine-year longitudinal study of nearly 300 participants. White matter is one component of the central nervous system, which consists of the brain and spinal cord and is responsible for transmitting information throughout the body. White matter is largely responsible for transmitting signals from one part of the brain to another. Researchers observed white matter hyperintensities on magnetic resonance imaging (MRI) scans on women who had experienced migraines. Hyperintensities generally appear as areas of high intensity on an MRI scan, which can denote lesions or areas of trouble.
Researchers found that migraines without aura were more likely to be associated with white matter hyperintensities. Migraines without aura, or common migraines, are characterized by a lack of visual or sensory symptoms and disruptions (auras) that occur before, during, or after a headache. Auras can also manifest as feelings of numbness, motor difficulties, and ringing in the ears, and are associated with classic migraines.
Among men, researchers found no association between migraine and MRI-measured white matter hyperintensities. And while that may seem like a bit of a gendered conclusion, there is an upside, particularly for women who experience migraines. Frequency of migraines, number suffered, severity, type of migraine, and treatment were not associated with any brain lesion or white matter hyperintensity progression. This means that, while migraines put women at more risk for these types of MRI-detected factors, someone who has had frequent migraines is not in more danger of these conditions.
The Expert Take
What's surprising, said Deborah Friedman, M.D., and author of a JAMA editorial on the study, was that white matter hyperintensities increased in women who had migraines without aura. "Several large studies have shown a slightly increased risk of stroke and heart disease in women having migraine with aura," said Friedman. "If the hyperintensities really represent small areas of ischemia, I would have expected them to progress in individuals experiencing aura."
Overall, these findings are reassuring. "While it is naturally upsetting to hear that you have 'spots in your brain' after having an MRI done for evaluation of headache," said Friedman, "if the spots are small and typical for those seen with migraine, they are probably not a cause for concern."
These results are reassuring for patients and physicians because even though women with migraine without aura are more likely to have deep white matter hyperintensities, the overall burden was quite small and most likely not significant. In addition, it was demonstrated that there was no increased incidence of stroke or decline of motor skills as a result of these hyperintensisties. Ultimately, these white matter hyperintensities, said Friedman, are less than those that are often associated with cerebrovascular disease and dementia.
Many potential studies could follow this, said Friedman. Observing this population in another 10 years would be beneficial for comparing long-term effects of migraines on white matter hyperintensities, as well as looking at a younger cohort who have carefully documented and characterized their conditions with clinicians. Comparing the effects of different treatments for migraines on these MRI scans would also be useful for future care, said Friedman.
Source and Method
Researchers conducted follow-up of a 2000 Dutch study called Cerebral Abnormalities in Migraine by taking 203 participants in a migraine group and 83 in a control group to undergo MRI scans in 2009. These MRI scans were used for comparing brain lesions in both groups, with comparisons being adjusted for a variety of factors like age and diabetes.
The average age of the participants in the migraine group was 57 years old, and 71 percent of the group were women, which is not strange considering the distribution of migraine incidence across the sexes.
In the control group, the mean age was 55 years old, and 69 percent were women.
While migraines put women at greater risk for developing brain lesions and white matter hyperintensities, the frequency and intensity of migraines suffered don’t affect the progression of lesions. And although women who suffer from migraines are more at risk for hyperintensities, they aren’t significant enough to put patients at great risk for stroke or decline of motor skills.
In 2011, researchers observed the effect of white matter brain lesions in migraine, and found that migraines with aura are consistently associated with these lesions.