Hot flushes early in menopause 'not a bad sign'

BMJ Group News

Women who get hot flushes or night sweats early on in the menopause may have a lower risk of heart disease and strokes than women who get them later on or not at all, a new study has found. However, some of the women in the study were taking HRT, which is known to increase the risk of heart problems, so that could have affected the results.

What do we know already?

About 6 in 10 women get hot flushes while they're going through the menopause. Women who get hot flushes seem to be more likely to have high blood pressure or high cholesterol, raising the possibility that they might be more at risk of heart disease or a stroke. A new study has tested this theory, by asking more than 60,000 women about their symptoms of the menopause.

What does the new study say?

Women who got hot flushes or night sweats early on during the menopause had a lower risk of a stroke, cardiovascular disease, and of dying during the study, compared with women who got no hot flushes at all. Women who got hot flushes or night sweats late in their menopause had a slightly higher risk of cardiovascular disease or dying during the study.

How reliable is the research?

Although the new study looked at a large group of women, there are several reasons to be cautious about its findings.

Just over 6 in 10 women in the study took hormone replacement therapy (HRT) at some point, and the side effects of HRT include an increased risk of blood clots, heart disease, and strokes. When the researchers looked just at women who hadn't taken HRT, most of the links between hot flushes and heart problems disappeared.

The changes in risk were fairly small. Several of the findings were just on the edge of the statistical tests researchers use to separate genuine results from a chance finding. And the group of women who got hot flushes late in their menopause was quite small, so the researchers say the results about this group should be treated as preliminary.

The study also relied on women thinking back to remember when their hot flushes had started. Researchers tend to get more accurate results if they ask people at the time, rather than relying on people's memories.

Where does the study come from?

The study is based on data from the Women's Health Initiative, a long-term study that looked at postmenopausal women. It was published in Menopause: The Journal of The North American Menopause Society.

Funding came from the US National Institutes of Health.

What does this mean for me?

The problems with the study make its results hard to interpret, but the researchers say that women who get hot flushes around the time of their menopause should feel reassured that they're unlikely to have an unusually increased risk of heart problems or a stroke.

It's not completely clear what the study means for women who get hot flushes some time after their menopause has started. The researchers say that doctors might have to start thinking of later hot flushes as a different medical condition.