"Studies show that people with migraine have double the risk of depression compared to people without migraine," said study author Larus S. Gudmundsson, PhD, with the National Institute on Aging and the Uniformed Services University of the Health Sciences, in Bethesda, Md. Gudmundsson is also a member of the American Academy of Neurology. "We wanted to find out whether having both conditions together possibly affected brain size."
For the study, 4,296 people with an average age of 51 were tested for migraine headache from 1967 to 1991; they were later assessed from 2002 to 2006 at an average age of 76 for a history of major depressive disorder (depression). Participants also underwent MRI, from which brain tissue volumes were estimated. A total of 37 participants had a history of both migraine and depression, while 2,753 had neither condition.
The study found that people with both migraine and depression had total brain tissue volumes an average of 19.2 milliliters smaller than those without either condition. There was no difference in the total brain volume when comparing people with only one of the conditions to people with neither condition.
"It is important to note that participants in this study were imaged using MRI once, so we cannot say that migraine and depression resulted in brain atrophy. In future studies, we need to examine at what age participants develop both migraine and depression and measure their brain volume changes over time in order to determine what comes first," said Gudmundsson.
Gudmundsson noted that some of the factors leading to a joint effect of migraine and depression on brain volume may include pain, brain inflammation, genetics and differences in a combination of social and economic factors. "Our study suggests that people with both migraine and depression may represent a unique group from those with only one of these conditions and may also require different strategies for long-term treatment."