Sex Change Can Cause Headache
Neurology
August, 2004
Abstract [Full Text] PDF
Abstract
NEW YORK - New research involving
male-to-female transsexuals lends further credence to the theory that sex
hormones are involved in migraine generation, physicians report in the medical
journal Neurology.
"We know that migraine is more frequent in women than in men," co-investigator
Dr. Tamara Pringsheim told Reuters Health, "so a lot of research goes into what
estrogen does to the brain."
A new way to examine this issue, she added, is to look at a population of
genetic males who take antiandrogens and estrogen to induce female sex
characteristics.
Pringsheim, at the University of Toronto, and Dr. Louis Gooren, at Free
University Amsterdam, distributed questionnaires regarding headache symptoms and
frequency to 50 transsexuals who had recently undergone sex reassignment
surgery, all of whom were taking hormonal therapy.
Thirteen (26 percent) fulfilled criteria for migraine or probable migraine,
similar to the number of cases of migraine in genetic females that would be
expected. In contrast, the expected number of cases of migraine in genetic males
is significantly lower.
Pringsheim and Gooren theorize that the increased prevalence of migraine is
related to the effect of hormone therapy on nitric oxide, a known migraine
trigger.
"Normally, vascular reactivity is different in men than in women because of
estrogen's effect on nitric oxide," Pringsheim explained. "Interestingly,
cardiologists who have studied vascular reactivity in male-to-female
transsexuals found something similar -- that they have enhanced arterial
activity -- so we know the hormones are doing something to the blood vessels."
She acknowledged that other mechanisms may be at play, such as the stress of
gender reassignment or adoption of a female gender role. Follow-up studies that
include headache histories and neurological examinations to confirm the
diagnosis of migraine should shed more light on these issues.
Citation: Neurology, August 10, 2004.
