Migraines: still a matter of hormones?

Faced with migraines, female vulnerability appears to be related to hormonal changes. In the dock, the secretion of estrogen, which varies during the cycle. The best evidence is the frequency of migraine called "catamenial, which occur over the rules or in the two days that precede them.

Why give estrogen migraine

Affecting 5 to 8% of women, these periodic headaches coincide with the sharp drop in estrogen that triggers the rules. They can be prevented by percutaneous application of estrogen.

Other evidence argue for the involvement of hormonal fluctuations. Thus women with migraines have almost always an improvement of their headaches during pregnancy and migraine tends to become less common after menopause.

Mechanism by which these hormones can they influence the occurrence of migraines? In an attempt to uncover this mystery, researchers at the University of Kansas artificially reproduced in mice phenomena vascular origin of migraine auras, that is to say that visual signs sometimes precede the migraine pain. They just presented their findings at the Congress of the American Academy of Neurology.

More than a thousand genes studied

The experiment was conducted on three groups of mice:

• Male mice;
• Female mice without ovaries (thus devoid of estrogen);
• Female mice without ovaries, but treated with estrogen.
  

Potassium chloride was administered into the brains of these animals to produce the electrical phenomena characteristic auras. The researchers then analyzed the expression of over a thousand genes. They have seen and, in males as in females without ovaries, some genes were activated and others inhibited, to mitigate the adverse effects of electrical damage.

In female mice treated with estrogen the same genes were modulated, but in an opposite direction, resulting in the secretion of substances with property to reduce inflammation and vascular dilatation responsible for migraine pain. Conversely, we can assume that the sharp decrease of secretion of this hormone during menstruation, promote changes in vascular origin of migraine. However, it should be noted that these results were obtained in experimental conditions far removed from migraine, especially catamenial forms that occur most often without aura ...

Runway magnesium

Researchers in New York have sought for their part, the presence of an ionized magnesium deficiency in 61 women with catamenial migraines *. They have seen and the deficit was more frequent (45% of cases) during the catamenial migraine, and during menstruation without migraine (14%) for non-menstrual migraine (15%) or between periods (15 %).

These results suggest that magnesium deficiency may play a role in some forms of menstrual migraine. They require however to be confirmed on a larger number of patients.

Head of the first study, Professor Loretta Mueller said that "75% of migraine sufferers are women and over half reported a hormonal origin. But we still do not know if we need to treat these headaches differently from men. Further studies may be able to answer ...