These are the first studies to find evidence of a genetic basis for hot flashes, and the first to look at genetic polymorphisms associated with hormone levels in healthy women with and without hot flashes.
The progesterone finding is of particular interest, said Flaws, because the medical community has focused almost exclusively on the role of low estrogen levels in bringing on hot flashes. Hormone replacement therapy, which is sometimes offered to women to alleviate hot flashes or other symptoms of the menopausal transition, may include one or more estrogens alone or in combination with progesterone or an analogue, progestin.
"We think there should be more studies looking at the role of progesterone in causing hot flashes," Flaws said.
The research team identified a second polymorphism, in a gene encoding an enzyme, 3-beta-hydroxysteroid dehydrogenase, which also is associated with an increase in hot flashes.
"People typically didnt think of hot flashes as having a genetic component," Flaws said. "Now we have some evidence that there is at least in part some genetics behind it."
In another paper, published in the journal Climacteric, the researchers used the same data to analyze the link between obesity and hot flashes. They had shown in an earlier study that obesity is associated with more frequent and intense hot flashes in midlife women. They now wanted to see what might be causing this effect: Did the higher incidence of hot flashes in obese women correlate with varying levels of specific hormones or other factors?
When looking at blood levels of specific hormones and related enzymes, the researchers found a significant link between obesity and hormone levels. Higher body mass index (BMI) was significantly correlated with higher testosterone and lower total estradiol, estrone, progesterone and sex hormone binding globulin (SHBG) in midlife women.
The rese
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Contact: Diana Yates
diya@uiuc.edu
217-333-5802
University of Illinois at Urbana-Champaign
24-Apr-2007