A woman in her 50s who has had a hysterectomy has much lower health risks when receiving estrogen-only replacement hormone therapy, compared to a woman in her 70s, whose has a higher risk of developing chronic disease, colorectal cancer, and even dying. Estrogen-only hormone replacement therapy (HRT) may even protect a woman in her 50s from breast cancer, researchers from Fred Hutchinson Cancer Research Center reported in JAMA (Journal of the American Medical Association).
The increased cancer and other risks for women in their seventies were found after gathering data from the seven-year follow-up from the WHI (Women’s Health Initiative). It involved only women who had had a hysterectomy. Therapy focused just on estrogen-only HRT, not the popular combination of estrogen/progestin. The research involved 10,739 women aged 50 to 79 years. They were randomly assigned with estrogen or a placebo, up to a maximum of 6 years.
The authors wrote:
“Our results emphasize the need to counsel women about hormone therapy differently depending on their age and hysterectomy status.”
This NIH (National Institutes of Health) funded research followed women for over 10 years – it is the most extensive assessment at the topic.
The authors stress estrogen-only HRT should not be taken just to protect against breast cancer. They concluded from their research that a woman in her 50s who has had a hysterectomy can receive estrogen-only HRT for up to six years relatively safely.
In 2004, the Women’s Health Initiative had shown that HRT did not reduce the risk of heart disease among peri-menopausal or post-menopausal females, but did raise stroke risk and the formation of blood clots. The study did away with routine use of HRT. From then on only women with severe symptoms were considered, and even then, with very low doses and for as little time as possible.
Experts have known that estrogen-only HRT is safer than combination estrogen/progesterone HRT. However, estrogen-only HRT, which is linked to uterine cancer risk, can only be taken by women who no longer have a uterus – those with a history of hysterectomy. Even then, there appeared to be risks.
However, it seems that the risks related to estrogen-only HRT for women in their 50s who have had a hysterectomy are not as dangerous as previously thought, and if used for up to six years are relatively safe and beneficial. Studies have shown that these women have a lower risk of developing colorectal cancer, heart attack, and even dying when on estrogen-only HRT versus a placebo.
Author, Professor of Epidemiology, Andrea Z. LaCroix, of the Fred Hutchinson Cancer Research Center in Seattle, explained that a considerable number of females in America have had a hysterectomy by the time they are 70 years old.
The authors concluded:
“Among postmenopausal women with prior hysterectomy followed up for 10.7 years, CEE use for a median of 5.9 years was not associated with an increased or decreased risk of CHD, deep vein thrombosis, stroke, hip fracture, colorectal cancer, or total mortality. A decreased risk of breast cancer persisted.”
Emily S. Jungheim, MD, and Graham A. Colditz, MD, DrPH interpret the new WHI findings differently. The women in the WHI were not taking HRT for the same reason as women do today. They ask whether the women who experience severe menopausal symptoms are the same as the women who enrolled in the WHI. They doubt it.
They add that current estrogen is not the same as Premarin used in the WHI, making it hard to make any proper comparisons or conclusions.
The authors of the first article say there will never be very large studies of modern HRT forms. The best evidence comes from this large trial, which produced reassuring data for females in their 50s with a history of hysterectomy taking estrogen-only HRT. There is no evidence that more natural estrogen forms are any safer. They should be seen as equal until new evidence appears.
Women with severe menopausal symptoms should discuss available options with their doctors – and there are options, the authors stress.
Andrea Z. LaCroix, PhD; Rowan T. Chlebowski, MD, PhD; JoAnn E. Manson, MD, DrPH; Aaron K. Aragaki, MS; Karen C. Johnson, MD, MPH; Lisa Martin, MD; Karen L. Margolis, MD, MPH; Marcia L. Stefanick, PhD; Robert Brzyski, MD, PhD; J. David Curb, MD, MPH; Barbara V. Howard, PhD; Cora E. Lewis, MD, MSPH; Jean Wactawski-Wende, PhD for the WHI Investigators
JAMA. 2011;305(13):1305-1314. doi: 10.1001/jama.2011.382
Written by Christian Nordqvist