Aug. 8, 2007 -- Women may get more migraines than men because their brains are quicker to release the trigger that begins the migraine cycle.
Women are three times as likely as men to suffer from migraine headaches, and a new study suggests the reason may be that their brains are faster to activate the cascading waves of activity thought to cause migraine pain as well as other migraine symptoms.
Researchers say migraines were once thought to be caused by constriction and dilation of blood vessels. But advances in brain imaging technology now suggest that migraines may start as a result of brain excitability.
People with migraines show dramatic waves of brain activity that spread across the surface of the brain -- known as cortical spreading depression (CSD). This depression is thought to trigger not only the severe pain associated with migraines but also the visual symptoms, dizziness, and difficulty concentrating often associated with migraines.
New Target for Treatment?
In a study published in the Annals of Neurology, researchers found that compared with male mice, female mice had a much lower threshold for releasing the CSD trigger.
"The results were very clear," says researcher Andrew Charles, MD, director of the Headache Research and Treatment Program in the UCLA department of neurology, in a news release. "The strength of the stimulus required to trigger CSD in males was up to two or three times higher than that required to trigger the response in females."
Researchers say many factors may reduce the CSD threshold in both sexes, such as genes, hormones, and environmental triggers like stress, diet, and changes in sleep patterns.
"Our results suggest that the female brain has an intrinsic excitability that predisposes them to migraine that may not be simply linked to a specific phase of the menstrual cycle," says Charles.
Researchers say if these results are confirmed in future studies this triggering mechanism may be a new target for migraine treatment.
- Suffer from migraines? Join others like you for expert information and support on WebMD's Migraines: Indie Cooper-Guzman, RN, message board.