Study Probes Links Between Hot Flashes, Heart Attacks

Women who have early hot flashes seem to have decreased risk of heart attacks.

February 25, 2011, 11:41 AM

Feb. 25, 2011— -- There just might be a plus side to the more bothersome symptoms of menopause depending on when you get them, new research suggests. A new study suggests that women who experience that crimson blush of a hot flash early on in their menopause experience seemed to have a lower risk of heart attack.

"The timing of hot flashes may make a big difference in terms of what they signify in terms of heart health," said Dr. Ellen Seely, of Harvard's Brigham and Women's Hospital, the senior author of the study.

Cardiovascular disease is the leading cause of death in women, and the risk increases dramatically after menopause. The study found a woman's risk of heart attack rises depending on when hot flashes begin in menopause.

The study, which analyzed data from more than 60,000 women over an average of almost 10 years. Women were asked to recall their symptoms -- like hot flashes and night sweats -- in questionnaires about their health. The women were in their early 60s on average, about 14 years after the start of menopause.

Dr. Sharonne Hayes, from the Mayo Clinic's department of cardiovascular diseases, said the results of the study add to the growing understanding of the complicated relationship between symptoms of menopause and heart attacks later in life.

"What it does tell us is that the interplay between hot flashes and night sweats and future cardiovascular risk and menopause is much more complex than we thought it was before," she said, but cautioned more research is needed.

The finding contradicts previous studies which suggested that hot flashes and night sweats are associated with increased heart attacks and stroke. While cardiologists are intrigued by, they warn it's too early to fully understand the link. This study should "reassure women who may have been concerned by older studies" about the relationship between menopause symptoms and the increased risk of heart disease, Hayes said.

More than one-third of the women surveyed remembered displaying early menopausal symptoms, hot flashes at the onset of menopause that ended before they enrolled in the study. Just 1,391 women showed late symptoms. About 2.5 percent of women with early symptoms had heart attacks, compared with 3.4 percent of women with no symptoms and 5.5 percent of women with late symptoms.

Menopause A Good Time to Reassess Heart Health

Deadly heart attacks rose, too -- about 6 percent of the early symptom women who had heart attacks died, versus 8 percent of the symptomless women and 11 percent of the late symptoms group.

Hot flashes are triggered by hormonal changes. The brain sends messages to blood vessels on the surface of the skin to dilate. Seely, an endocrinologist from Harvard's Brigham and Women's Hospital, said by looking at blood vessels in the skin that are easier to see than those in the heart, the authors gained "a window into what was happening deep within the body" during menopause.

This study in particular depended on women recalling whether they had symptoms, Hayes said, women "who are 10 or 15 years out of menopause may not remember it quite as well."

Menopause is an important time for women to take a look at their personal health, Hayes said.

"Whether or not hot flashes increase the risk or decrease the risk for heart disease is important, but women at the time of menopause are reassessing their health because of their symptoms," she said. Women should remember that the things they choose to do during this transitional moment in their lives -- like exercise and eat healthy meals, quit smoking, and address other heart disease risk factors like high cholesterol and blood pressure, "are much, much more powerful than whether or not they have hot flashes."

The new research is part of the ongoing Women's Health Initiative observational study funded by the National Institutes of Health.

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