“Hot flashes are so, so common around the time of menopause and a lot of previous work has suggested that they increase certain markers of cardiovascular disease risk such as blood pressure or cholesterol levels,” says study researcher Emily Szmuilowicz, MD, an endocrinologist at Northwestern Memorial Hospital in Chicago. But “there was no increase in risk seen among women who had hot flashes throughout menopause, and women with hot flashes at the beginning of menopause seemed to have a lower risk of cardiovascular disease, stroke, and death.”
During a hot flash or hot flush, blood vessels near the skin's surface dilate to cool, producing a red, flushed look. Women may also start sweating to cool down their body. Exactly how -- or even if -- hot flashes may protect against heart disease is not known.
Women in the new study were divided into four groups including those who did not have hot flashes during menopause, those who had hot flashes only when they entered menopause, those who had hot flashes during early and late menopause, and those who developed hot flashes during the later stages of menopause.
Women whose hot flashes persisted throughout menopause were not at any increased risk for heart disease, stroke, or death, the researchers report. Women who had hot flashes only during early menopause were less likely to develop heart disease, stroke, or die. Those women whose hot flashes came on late in the course of menopause were at an increased risk for heart disease and death from any cause, the new study shows.
Some women in the study were taking hormone replacement therapy (HRT) and researchers did attempt to take this into account. Past or current use of hormones may affect hot flashes. What’s more, some forms of HRT have been associated with an increased risk of heart disease. “We are advising women who are appropriate candidates to use hormone replacement therapy early on and in the lowest dose possible for the shortest amount of time to alleviate their symptoms, but not for cardiovascular protection,” Szmuilowicz says.