Oct. 6, 2015 -- Menopausal women who have lots of hot flashes could face a higher risk for early-stage heart disease, a new study suggests.
The research is the first to compare the frequency of hot flashes with the thickness of the inner layers of the carotid arteries (which carry blood to your brain). The thickness of those layers is a sign of early heart disease.
In the new study, women in their mid-50s who had up to 12 hot flashes per day had thicker carotid artery layers than women with four or less flashes per day. The link seemed to hold up when researchers took into account things like age, race, weight, cholesterol levels, and blood pressure.
Those with less-frequent hot flashes were not considered at risk, says lead researcher Rebecca Thurston, PhD, from the University of Pittsburgh. “The women we need to pay close attention are the 'super flashers,'" those who say they have the symptom a lot. They need to be regularly screened for heart disease risk factors, she says.
The researchers presented their study's results at the North American Menopause Society 2015 Annual Meeting.
Details on the Women in the Study
All 304 of them were nonsmokers, in their mid-50s, and hadn't been diagnosed with heart disease. Most of them were postmenopausal, overweight, and had normal blood pressure.
The researchers detected their hot flashes through continuous monitoring and with electronic diaries. The women also had ultrasounds to check the thickness of their carotid artery layers.
Half the women reported no hot flashes. The other half said they had an average of four per day, although monitoring showed they were having an average of 10 per day.
"Women often under-report their hot flashes," Thurston says.
Still, it’s not clear whether treating the hot flashes would have any impact on underlying heart disease risk, she says.
It's very common for women to have hot flashes before they go through "the change" (perimenopause) and after it (postmenopause), says Mary Norine Walsh, MD, medical director of the heart failure and cardiac transplantation programs at the St. Vincent Heart Center of Indiana.
"The results of this very small study should be interpreted with caution," she says. Using carotid artery layer thickness to determine risk is controversial, Walsh says, and some of the women in the study may have had other heart disease risk factors that weren’t accounted for.
So the study results don’t signal a need for doctors to change the way they gauge a woman's risk for heart disease, she says.
Still, unlike in previous studies, Thurston's team continuously monitored women for hot flashes, which is a “more accurate measure,” says Taulant Muka, MD, from Erasmus University Medical Center in Rotterdam, the Netherlands. But the design of the study makes it unclear whether the hot flashes are a cause contributing to heart disease, or whether the hot flashes result from early-stage heart disease, Muka says.
These findings were presented at a medical conference. They should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.