Evidence favours safety of menopausal hormone therapy

In a reassuring finding, a long-term follow-up study says there is no increased risk of all-cause mortality from HRT

Menopausal women and their doctors can be reassured about the safety of hormone therapy, as a large and long-term study shows the treatment is safe for up to eight years.

Interest in menopausal hormone therapy plummeted after research in the early 2000s linked it to breast cancer and stroke.

But now, with the publication of the two-decade, follow-up analysis of 27,000 of the same women, clinicians are saying it is safe and beneficial to use, particularly if started at the time of menopause.

“We have now got sufficient evidence that for eight years, at least, we can comfortably prescribe HRT,” said Dr Magdalena Simonis, honorary research fellow in the department of general practice at the University of Melbourne.

Dr Simonis said this was an important message for patients, because “if that takes you from age 51 to 59, then that’s a pretty significant chunk of your productive life”.

The women studied were randomly allocated to take either a placebo, oestrogen alone or a combination of oestrogen and progesterone, and received therapy for an average of about seven years.

There was no increased risk of all-cause mortality or specific-cause mortality at the end of the 18-year follow-up, the researchers found. In fact, women who started hormone therapy younger had a 39% decreased risk of early death over the short-term compared to older women.

Even at the end of the follow-up, mortality rates were still slightly lower for women who started hormone therapy younger but it was not statistically significant.

The early Women’s Health Initiative trial on combination therapy was stopped early because of an increased breast cancer risk, and the initial oestrogen-alone study was also stopped because the researchers found women on the treatment were more likely to have a stroke.

But by taking a long-term look at these women’s health, the researchers could see that their overall mortality, as well as total cancer and cardiovascular mortality, was unaffected.

“All-cause mortality is a critically important summary measure representing the net effect of hormone therapy on serious and life-threatening health conditions,” the authors explained.

“This is a very positive thing for menopausal women,” Dr Simonis said. “Because what we found was when HRT fell out of favour, a lot of women who had severe symptoms were actually going on to low dose antidepressant medication to cope.”

“Whereas what they needed was HRT.”

“What we do know is that HRT is protective against heart disease in the early menopausal years, we know it’s one of the most effective ways of preserving your bone density,” she said. “It also helps women with respect to vaginal atrophy, which has a dramatic impact on menopausal women.”

The main risk for women was deep vein thrombosis, according Professor Simonis, but that this is similar to the discussion a doctor would have with their patients on the contraceptive pill.

The authors concluded that these findings support menopausal hormone therapy for the one in two women who suffer significant menopausal symptoms, but said the evidence did not support its use for preventing chronic disease or mortality.

JAMA 2017; online 12 September