A major research study in 2002 caused a stir after finding that hormone therapy in older women was associated with elevated risks for heart attack, stroke, breast cancer and blood clots.

The result? Many women gave up the drugs, and some doctors stopped prescribing them.

But new evidence is now coming to the defense of hormone therapy — at least for women in the early years of menopause. That’s when hot flashes, night sweats and other problems like interrupted sleep are most intense.

Research published this week in the journal Cochrane Library found that women who start hormone therapy within the first 10 years of menopause may receive a small amount of protection against heart attack and death from heart disease, and no increased risk of stroke. Women further out from menopause, however, saw no heart-related benefits and had a slightly increased risk of stroke.

The findings reviewed results from a variety of studies involving more than 40,000 postmenopausal women worldwide. All women, regardless of when they started taking hormones, had an increased risk of blood clots in the deep veins and lungs.

Hormone therapy used to be routine for postmenopausal women. Doctors didn’t think twice about prescribing it to help prevent chronic conditions such as heart disease, stroke and dementia. That all changed when a 2002 report from the Women’s Health Initiative study, or WHI, raised concerns among both providers and their patients.

More than one in five postmenopausal women took hormones in 1999-2000, according to the National Health and Nutrition Examination Survey conducted by the Centers for Disease Control and Prevention. By 2010, that number had plummeted to fewer than one in 20.

JoAnn Manson, M.D., chief of preventive medicine at Harvard-affiliated Brigham and Women’s Hospital and a lead investigator on the WHI study, said some of that decline was appropriate. But although the WHI study clearly showed that hormone therapy should no longer be used to prevent cardiovascular diseases and other ills of aging, Manson said the results did not imply that hormone therapy should be entirely off-limits when treating bothersome menopausal symptoms.

“The [WHI] results were inappropriately extrapolated to healthy women in early menopause who have significant symptoms, for whom hormone therapy remains the most effective treatment,” said Manson, also an AHA volunteer. “Many were taken off hormone therapy or denied hormone therapy when they asked to initiate it.”

She noted that most women in the WHI study were in their 60s and 70s and did not have moderate or severe menopausal symptoms. Follow-up data published in 2013 found that short-term hormone therapy posed less risk to younger users in the trial.

Manson recently co-led another study called KEEPS, short for Kronos Early Estrogen Prevention Study. Among the findings of the trial was a significant reduction in moderate to severe hot flashes, improvement in mood and some favorable changes in sexual function for women who took hormones soon after menopause.

The results, published last July in the Annals of Internal Medicine, offer reassurance that hormone therapy — taken at a low dose for a limited time — is not dangerous for healthy women in early menopause, said Cheryl Bushnell, M.D., a neurologist and director of the Stroke Center at Wake Forest Baptist Medical Center.

“It’s fine to give them hormone therapy,” said Bushnell, who helped write the AHA’s stroke prevention guidelines for women.

There are some caveats, however. Experts still caution that hormone therapy should not be used in certain women of any age, such as those with a history of heart disease, stroke or breast cancer. Doctors encourage those women with menopausal symptoms to instead consider nonhormonal treatments, such as antidepressants.

Experts suggest that women who are experiencing bothersome menopausal symptoms talk to their doctors about the best treatment for them based on their individual risks and preferences.

In general, Manson said, the quality of life benefits are likely to outweigh the risks for younger healthy women with distressing symptoms.

“Unless they have contraindications, younger postmenopausal women seeking symptom relief tend to do well on hormone therapy,” Manson said.

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