Researchers in Berlin have identified migraines before or during menstruation could be caused by fluctuations in hormones, in particular, oestrogen
Scientists from Charité – Universitätsmedizin Berlin has completed a study, recently published in the journal Neurology,* and revealed women who experience migraines have higher levels of Calcitonin Gene-related Peptide(CRGR) during menstruation.
CGRP is a neurotransmitter that is known to play an important role in triggering migraines.
“Animal models suggest that fluctuations in female hormones, especially oestrogen, lead to an increased release of CGRP, an inflammatory neurotransmitter, in the brain,” explains study lead Dr. Bianca Raffaelli of the Headache Center at the Department of Neurology with Experimental Neurology.
“CGRP is a naturally occurring substance in the body, and when a person has a migraine attack, increasing levels are released, significantly dilating – or widening – the blood vessels in the brain. This causes an inflammatory response that could be one of the reasons behind the severe headaches people experience with migraine.”
Increased CGRP levels during menstruation
The group studied a total of 180 women to determine whether the link between female hormones and the release of CGRP also exists in humans.
The researchers tested the CGRP levels in migraine patients twice during their cycle, with one measurement taken during menstruation and the other during ovulation.
When the data were compared to those women who do not suffer migraines, it became clear that migraine patients have significantly higher concentrations of CGRP during menstruation than healthy subjects.
“This means that when oestrogen levels drop immediately before the start of a menstrual period, migraine patients release more CGRP,” says Raffaelli, who is also a fellow with the Clinician Scientist Program jointly operated by Charité and the Berlin Institute of Health (BIH) at Charité.
“This could explain why these patients suffer more migraine attacks just before and during their monthly period.”
In women who take oral contraception, by contrast, there are hardly any fluctuations in oestrogen levels.
“The data will still need to be confirmed by larger studies, but our findings do suggest that the release of CGRP depends on hormonal status in humans, as it does in the animal model,” Raffaelli notes. “Taking birth control pills and the end of menopause do in fact bring relief for some female migraine patients. But as our study also shows, there are women who suffer from migraine even without any hormonal fluctuations.
“We suspect that other processes in the body play a role in triggering attacks in those patients. After all, CGRP isn’t the only inflammatory peptide that can cause a migraine attack.”
The researchers also plan to take a closer look at CGRP levels in men of varying age groups.