More
Shots Against Long-Term HRT
Two
new reviews of combination hormone replacement therapy and its effect
on heart disease and other problems, published in August in
two leading medical journals, strongly support the recent conclusions
of the Women's Health Initiative (WHI) study, which finds more harm
than benefit in long-term HRT use.
The
WHI clinical trial of estrogen used with progestin was halted last month,
5.2 years into the planned eight-year study, because it found that women
using the combination HRT (specifically, Prempro) were more likely to
have breast cancer, heart attack, stroke, and blood clots even though
they were protected against osteoporosis and colon cancer.
The
new analyses, published in a recent issue of the Annals of Internal
Medicine and a recent issue of the Journal of the American
Medical Association (JAMA), lend more support to the findings
in the WHI study, the researchers say.
The
Annals of Internal Medicine review addresses primarily
cardiovascular disease risk, while the JAMA review
also considers other potential effects of long-term HRT use, such as
osteoporosis and colon cancer prevention, and includes in its analysis
the WHI study.
In
both reviews, the researchers combed through medical literature from
1966 to 2000 or 2001 and kept only the most scientific studies of HRT
to review.
"For
prevention of chronic conditions, there aren't a lot of reasons to take
it," says Dr. Heidi D. Nelson, an author of the JAMA
review and an associate professor of medicine and medical informatics
and outcome research at the Oregon Health & Science University in
Portland.
"I
want to make clear we were only looking at HRT for the prevention of
chronic conditions," she adds, and not for short-term relief of hot
flashes and other menopausal symptoms, which is what HRT is often used
for.
The
Annals of Internal Medicine review, led by Dr. Linda
L. Humphrey, associate professor of medicine at Oregon Health &
Science University and the Portland Veterans Affairs Medical Center,
concludes that HRT has no benefit in the primary or secondary prevention
of coronary heart disease.
The
findings from the new analyses contradict common wisdom, the authors
acknowledge.
"The
thing so exciting a few years ago is that everyone thought [HRT] helped
your heart," Nelson says. "Our review found no benefit for the heart.
That takes a huge bit of the luster away from taking something long-term.
It does help your bones. That's been consistent in all the studies.
But there are other things you can do [to preserve bone density]. What
really has changed over the past few years is the realization that there
is more evidence for harm."
"The
harms are not common," she adds. "When you calculate the number of people
who are harmed, it is not a large number. For instance, 1.5 women per
year per 10,000 women will have a blood clot. All the studies agree.
That's 1.5 more women than you would expect [without HRT]."
The
decision of whether or not to take HRT today, Nelson says, "is a different
decision than it was before" for prevention of chronic conditions.
She
is talking, she stresses, only about combination therapy using estrogen
plus progestin. The arm of the WHI study that is evaluating estrogen-only,
given to women who do not have a uterus, is continuing. (Women with
an intact uterus are given combination therapy because taking estrogen
alone raises the risk of endometrial cancer.)
For
women deciding whether to continue on HRT for heart disease prevention,
the decision should be straightforward, says Humphrey.
"When
you put all the data together about heart disease prevention and HRT,
there was no benefit for primary prevention," she says. That is, women
without heart disease can't expect HRT to prevent them from getting
it.
Both
researchers say some women may have quality-of-life issues for continuing
to take HRT for more than a few years. Some say they simply feel better
on the therapy, having fewer mood swings, less vaginal dryness, and
better libido.
The
new analyses probably will not change the advice physicians are giving
women on a case-by-case basis about HRT based on their risks, says Dr.
William Parker, a gynecologist at Santa Monica-UCLA Medical Center who
is very familiar with HRT research. These new analyses, he says, echo
"what has already been said." And the WHI study, he says, was the more
scientifically sound one.
The
analyses, he said, are what experts call meta-analyses, or an evaluation
of previous studies that may differ in scientific quality in reaching
their conclusions.
"Meta-analyses
have inherent flaws," Parker says. "It's kind of like comparing apples
and oranges."
But
the meta-analyses done by Humphrey and Nelson will be used by the US
Preventive Services Task Force, an independent panel of experts,
which is in the process of updating its HRT recommendations.
The
US Department of Health and Human Services has already
announced it will hold a series of public forums to consider the future
of HRT, beginning in the fall.
Always
consult your physician for more information.
In
Other Heart Health News For Women:
Heartening
News on Vitamin E
If
you are a woman who is not getting enough vitamin E in your diet, you
could be increasing your risk of cardiovascular disease.
A study
in the September issue of the American Journal of Clinical Nutrition
found that low vitamin E intake in middle-aged women is a risk factor
for early atherosclerosis.
The
study included 307 southern Italian women, average age 56, with no clinical
history of cardiovascular disease. The women did not take any vitamin
supplements containing the antioxidant vitamins A, C, or E.
Their
average daily intakes and plasma concentrations of antioxidants were
assessed, using questionnaires and blood samples. They were also given
ultrasound examinations of the carotid arteries and branches.
The
researchers found that 66 percent of the women had atherosclerotic plaques
at one or more sites in the carotid arteries. Women with the lowest
vitamin E intake were more than twice as likely to have plaque in their
carotid branches.
There
was no connection between such plaque in the women's carotid arteries
or branches and their intake of vitamins A and C, the study found.
The
women in the study reported their main sources of dietary vitamin E
were legumes, vegetables, and olive oil.
The
study authors say only people with low intakes of vitamin E could benefit
from increasing their intake of the vitamin. Before anyone alters their
diet or takes antioxidant supplements, they need to assess their daily
vitamin E intake with their physician, the authors say.
Always
consult your physician for more information.
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