Migraine-related brain changes may not impair mental abilities
Women with migraines did not appear to experience a decline in cognitive ability over time compared to those who didn't have them, a nine-year follow up study has revealed.
The study funded by the National Institutes of Health also showed that women with migraine had a higher likelihood of having brain changes that appeared as bright spots on magnetic resonance imaging (MRI),.
"The fact that there is no evidence of cognitive loss among these women is good news," said Linda Porter, Ph.D., pain health science policy advisor in the Office of the Director at the National Institute of Neurological Disorders and Stroke (NINDS), which provided funding for the study.
Mark C. Kruit, M.D., Ph.D., one of the principal investigators, and a neuroradiologist from Leiden University Medical Center, the Netherlands, which led the study, said, "An important message from the study is that there seems no need for more aggressive treatment or prevention of attacks."
Dr. Kruit and associates evaluated MRIs for changes in the white matter, brainstem, and cerebellum that appeared on the scans as bright spots known as hyperintensities. Previous studies have shown an association between such hyperintensities and risk factors for atherosclerotic disease, increased risk of stroke and cognitive decline.
The extent of MRI brain findings increased slightly with time, according to the population-based study that tracked 286 men and women with and without migraines.
Men with migraines had no greater incidence of such changes compared with age-and sex-matched controls. Although female participants with migraine in this study were more likely to have hyperintensities, there was no clear relation to the frequency of migraine attacks, the type of migraine or how they were treated.
Standardized measures of cognitive abilities such as memory, concentration, and attention did not show significant losses among people with migraine-associated lesions compared to those without migraine. The brain changes that give rise to the bright spots seen on MRI are unknown. More research is needed to find out if these are related to ischemia and ischemic stroke risk, according to the researchers.
The study found that women with migraines were twice as likely as those without such attacks to have an increase in the volume of diffuse white matter changes. However, this increase was still very small, said one of the study's investigators, Lenore J. Launer, Ph.D., chief of the Neuroepidemiology Section at the National Institute on Aging (NIA).
CAMERA-2 also showed no correlation between new brain lesions and migraine frequency. This finding may be due to the fact that structural changes to the brain arise not with each new migraine attack, but are the result of an ongoing process that occurs even during periods between attacks, Dr. Kruit said.
The study participants aged, making it difficult to tease out brain changes that are specifically attributable to migraine. That is because age, as well as hypertension and diabetes, are also known risk factors for white matter changes, Dr. Launer explained.
Sixty percent of control females without migraine showed progression of white matter lesions as compared to 77 percent of those with migraine.
These findings add to the increasing amount of data that migraine, particularly in women, is progressively related small blood vessel changes, the researchers wrote in the paper.
The findings appeared recently in the Journal of the American Medical Association.