Hormone Therapy Won't Prevent Disease After Menopause: Analysis
But follow-up research shows that short-term use for hot flashes remains an option
"Many women have a hard time finding a doctor who'll prescribe it," Manson said. She added that these latest findings paint "a clearer picture of what the message should be."
The results are based on about 16,600 women who were randomly assigned to take either estrogen/progestin or placebo pills, and more than 10,700 who took either estrogen alone or a placebo. The women were on hormone therapy for about six to seven years before the WHI trials were stopped, and Manson's team followed them for six to eight years beyond that.
Over the longer term, most of the risks originally tied to hormone replacement therapy declined -- and so did the benefits, such as lower risks of hip fractures and diabetes. The exception was breast cancer risk, which remained higher for women who used estrogen and progesterone. Across the study period, there were 434 cases of breast cancer among those women, versus 323 among placebo users.
The findings were "more favorable" among relatively younger women, aged 50 to 59, who used estrogen only, the researchers said. They actually had a slightly lower rate of heart attack and fewer deaths, versus women in their 50s who used placebo pills.
But those differences were small, and Manson said there are concerns about other hormone therapy risks, even in younger women -- such as the risk of blood clots that could cause a stroke or travel to the lungs.
So, no one should take hormones for the sake of cutting ling-term disease risks, said Dr. Elizabeth Nabel, who wrote an editorial published with the study.
"Even though short-term use of this therapy may be helpful in [menopause] symptom relief, this new, 13-year follow-up study clearly does not support the long-term use of hormone therapy for the prevention of chronic diseases," said Nabel, president of Brigham and Women's Hospital.
For a drug to be used to prevent, rather than treat, disease, the benefits have to clearly be worth it, Manson noted. "We have to set the bar very high," she said.
Studies are still looking into whether hormone therapy might cut relatively younger women's disease risks -- including whether lower doses or different "routes of delivery" might work better.
It's thought, Manson said, that hormone patches might be safer than pills, because they may not carry the same blood-clot risk. But there is no conclusive evidence that patches should be used for disease prevention either, she stressed.