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Hormone Therapy: The Answers Are In Few things are more upsetting than having to
revise your beliefs, especially when your own physician may have encouraged
those beliefs, and an array of experts cited scientific evidence to back
them up. In July the Women's Health Initiative, the best study so far
of hormone replacement therapy (HRT) in healthy women, showed that the
treatment actually increases the risks of heart disease and breast cancer,
outweighing any protection against fractures and colon cancer. True, the
study showed that if taken for less than four or five years, hormone therapy
is a reasonably safe way to deal with menopausal symptoms. But this is
a far more modest benefit, overall, than most women had been led to expect.
Now women are asking, "What should I do?"
and "Have I done myself real damage in taking this stuff?" The
answer to the first question is complicated; the answer to the second
is probably no. How we got here About two out of five postmenopausal American
women are on hormones, or were until last summera trend that began
its upward trajectory some 30 years ago. Hormone therapy comes in two
types: estrogen alone (ERT) or the combination of estrogen and progestin,
known as HRT. The idea that taking estrogen after menopause helps protect
women against osteoporosis has been well established. And there's logic
to the idea that it should also protect against cardiovascular disease.
Numerous studies have found benefits. And hormone therapy can counteract
unpleasant (and occasionally unbearable) menopausal symptoms, such as
hot flashes, vaginal dryness, night sweats, and mood swings. There are many other reasons why hormone therapy
has been so popularoptimism being only one of them. There were claims
(totally unfounded) that it would keep a woman "forever feminine"
and "forever young." The companies that made the hormones helped
promote such notions, and journalists quickly joined the parade. Understandably,
women want to stay healthy into old age, especially now that it's reasonable
to expect to live 30 or more years past menopause. Doctors were (and are)
eager for medications that will help. All along, however, there were questions. ERT
was shown to promote cancer of the uterus, but it turned out that this
effect could be countered by adding progestin to the pillhence HRT.
(Estrogen by itself was reserved only for women who had had hysterectomies.)
Whether HRT raised the risk of breast cancer was another troubling problem.
Many doctors were reluctant to prescribe HRT for women at high risk for
breast cancer. But as a way to reduce the risk of cardiovascular disease
and bone loss, ERT and HRT continued to look promising. Yet, until now, one thing was always missing:
a large-scale, well-designed clinical trial that tested the safety and
effectiveness of hormone therapy as a way to prevent disease in healthy
women. No matter how carefully conducted, all the studies had been observational.
That is, they followed groups of women taking hormones and recorded outcomesa
valuable kind of research, but never definitive. For example, women who
took HRT tended to lead healthier lives, and maybe this, rather than HRT,
is what benefited their hearts. At last, the National Institutes of Health
began the needed clinical trial, called the Women's Health Initiative.
In part of this study, women were randomly assigned to take HRT (Prempro,
the most popular form) or a placebo. The trial was to have lasted eight
and a half years, but was terminated after a little more than five years
to protect the participants from further risk, specifically the rising
risk of breast cancer. What the study found The news is not as terrible as some reports
have claimed. At least we know some things for sure now. Women and their
doctors have long known or strongly suspected that hormone therapy increases
the risk of breast cancer. What's new is the increased risk of cardiovascular
diseasethough in recent years there had been studies suggesting
that this would turn out to be the case. Here are the main findings: During
the five years, women on HRT had slightly more heart attacks, stroke,
and blood clots. But the increase in risk was very small. And there were
no extra deaths. HRT taken
for more than four years slightly increased the risk of breast cancer.
Though
HRT helped prevent fractures, the effect was small and would last only
as long as you take the hormones. Women on
HRT had a slightly lower incidence of colon cancer. What to do
UC Berkeley Wellness Letter, October 2002
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