By Julie Steenhuysen
CHICAGO (Reuters) - The risks of taking hormone therapy to prevent heart disease and osteoporosis in post menopausal women far outweigh the benefits and such treatment is not recommended, according to new guidelines from an influential panel of U.S. health advisers.
The guidelines from the U.S. Preventive Services Task Force, published on Monday in the Annals of Internal Medicine, reaffirm the group's 2005 guidelines recommending against the treatment.
They apply only to hormone therapy for prevention of chronic disease. They do not apply to the use of hormones to treat symptoms of menopause, such as hot flashes or vaginal dryness, or to women under age 50 who have had a hysterectomy.
"Our recommendation is the same as it was for 2005," said Dr. Kirstin Bibbins-Domingo, a researcher and internist at the University of California San Francisco and a member of the task force.
"In evaluating the evidence for both the benefits and the harms of these therapies, the task force recommends against these therapies for the purpose of preventing chronic conditions," she said in a telephone interview.
The guidelines are based on a review of the most recent scientific evidence, which showed that estrogen alone and estrogen plus progestin reduce the risk of bone fractures, but increase the risk for stroke, blood clots, gallbladder disease and incontinence.
While taking estrogen alone reduced the risk for breast cancer, estrogen plus progestin increased the risk for dementia and breast cancer.
Doctors say the guidelines largely reflect current medical practice, and are not likely to stir controversy, unlike some of the task force's previous recommendations on the use of screening tests for breast cancer and prostate cancer.
The recommendations address the belief that giving older women hormone replacement therapy might prevent some age-related diseases, such has heart disease and dementia.
But the largest trial to look at the practice, called the Women's Health Initiative study, in 2002 found that women who took estrogen plus progestin for five years had higher rates of ovarian cancer, breast cancer, strokes and other health problems.
That study sharply cut sales of popular hormone treatments such as Premarin and Prempro, previously sold by Wyeth and now owned by Pfizer Inc.
'THRESHOLD FOR SAFETY'
"When it comes to preventing disease in otherwise healthy women, the threshold for safety is high," Bibbins-Domingo said.
"In this case, the harms - the risk of blood clots, gallbladder disease, those types of things - led us to conclude that, on balance, the harms outweigh any potential benefit."
She added that for conditions such like heart disease and dementia, there was no evidence of any benefit.
Dr. JoAnn Manson, chief of preventive medicine at Brigham and Women's Hospital and a professor at Harvard Medical School who worked on the WHI study, said the latest recommendations track with current medical practice.
"Most professional societies already advise against the use of hormone therapy for chronic disease prevention," Manson, who is not on the task force, said in a telephone interview.
These groups include the American Heart Association, the American Congress of Obstetricians and Gynecologists and the American Academy of Family Physicians.
Manson said it is important to distinguish between hormone therapy used for prevention of chronic disease and short-term use of hormone therapy to treat menopause symptoms, which the guidelines do not address.
She said many of the same professional societies that caution against use of hormone therapy for prevention endorse its use in healthy women whose lives are being disrupted by symptoms of menopause.
"That is the really key point here," she said.
Because of the potential risks, doctors prescribe hormone therapy for menopause symptoms at the lowest possible dose for the shortest period of time.
"We understand that there is a different balance of benefits and risks when hormone therapy is used for short-term symptom management versus long-term disease prevention," Manson said.
"Unless a woman has moderate to severe hot flashes and menopausal symptoms and is going to derive a quality-of-life benefit, it is likely that the risk of hormone therapy will outweigh the benefits."
Because the average age of women in the Women's Health Initiative study was 64, some doctors question whether the risks of harm apply to younger women taking hormone therapy for menopause symptoms.
The task force said more study is needed on the effects of hormone therapy in younger women.
(Reporting by Julie Steenhuysen; editing by Christopher Wilson)