 |
Questions and Answers
About Estrogen-Plus-Progestin Hormone Therapy
Q. What is the purpose of the WHI study on
combination hormone therapy?
A. The long-term studies in the WHI were initiated
because over the years a number of research studies presented a complicated
picture of the risks and benefits of hormone therapy, and its continued use for
prevention of cardiovascular diseases was controversial. This situation led the
NIH to conduct a large clinical trial of the risks and benefits of hormone
therapy. The WHI set out to examine the long-term effect of estrogen plus
progestin on the prevention of heart disease and hip fractures, while
monitoring for possible increases in risk for breast and colon cancer. The
estrogen plus progestin regimen was given to women who have a uterus since
progestin is known to protect against endometrial cancer, a known effect of
unopposed estrogen. A separate study of estrogen alone in women who had a
hysterectomy was also begun.
 Back to Top
Q. Why were the women in the WHI estrogen-plus-progestin study told to stop study pills in July 2002?
A. When it reviewed the study data in May 2002, the
WHI Data and Safety Monitoring Board saw an increased risk of breast cancer in
women taking estrogen plus progestin. The Board also saw that the previously
identified risks for heart attacks, strokes and blood clots to the lungs and
legs had persisted. Therefore, in the judgment of the Board, the overall risks
outweighed the benefits of taking estrogen plus progestin.
Back to Top
Q. What were the main findings in the WHI
study on estrogen-plus-progestin?
A. The main findings show that compared to women
taking placebo pills:
- The number of women who developed breast cancer was
higher in women taking estrogen plus progestin.
- The numbers of women who developed heart attacks,
strokes, or blood clots in the lungs and legs were higher in women
taking estrogen plus progestin.
- The numbers of women who had hip and other fractures or
colorectal cancer were lower in women taking estrogen plus progestin.
- There were no differences in the number of women who had
endometrial cancer (cancer of the lining of the uterus) or in the number of
deaths.
Back to Top
Q. What are the increased risks for women
taking estrogen-plus-progestin?
A. For every 10,000 women taking estrogen plus
progestin pills:
- 38 developed breast cancer each year compared to 30
breast cancers for every 10,000 women taking placebo pills each year.
- 37 had a heart attack compared to 30 out of every 10,000
women taking placebo pills.
- 29 had a stroke each year, compared to 21 out of every
10,000 women taking placebo pills.
- 34 had blood clots in the lungs or legs, compared to 16
women out of every 10,000 women taking placebo pills.
Back to Top
Q. What are the reduced risks for women
taking estrogen-plus-progestin?
A. For every 10,000 women taking estrogen plus
progestin pills:
- 10 had a hip fracture each year, compared to 15 out of
every 10,000 women taking placebo pills each year.
- 10 developed colon cancer each year, compared to 16 out
of every 10,000 women taking placebo pills.
Back to Top
Q. What are the conclusions from these
findings?
A. The main conclusions are:
- The estrogen plus progestin combination studied in WHI
does not prevent heart disease.
- For women taking this estrogen plus progestin
combination, the risks (increased breast cancer, heart attacks, strokes, and
blood clots in the lungs and legs) outweigh the benefits (fewer hip fractures
and colon cancers).
Back to Top
Q. What were the actual hormones that
women in the estrogen-plus-progestin study were taking?
A. Women who were randomized to receive active
hormones were taking conjugated equine estrogens 0.625 mg each day and
medroxyprogesterone acetate 2.5 mg each day.
This is the most commonly prescribed postmenopausal hormone
therapy in the United States for women who have a uterus (used each day by more
than six million women).
Back to Top
Q. When did the increased risk of breast
cancer become apparent for women taking estrogen-plus-progestin compared to
women taking placebo pills?
A. There was no difference in the development of
breast cancer during the first 4 years between women taking estrogen plus
progestin and those taking placebo pills. After that time, the numbers began to
increase. After an average of 5.2 years, there was an increased risk of breast
cancer in women taking estrogen plus progestin compared to those taking placebo
pills.
Back to Top
Q. Do you have recommendations about
other hormone alternatives (lower-dose estrogens, micronized progesterone,
natural hormones)?
A. We cannot make specific recommendations about
other hormone medications, such as different estrogens or progestins. We also
cannot make recommendations about hormones women take in lower dosages or in
different ways, such as patches instead of pills.
Futher, without scientific clinical trial data, one cannot
assume that alternative estrogen plus progestin treatments are any safer than
those studied in WHI.
Back to Top
Q. I am taking prescription hormones,
what should I do?
A. We recommend that you talk with your health care
provider about your individual health risk profile and the hormones you are
currently taking. The FDA's advice on hormone therapy should be considered.
Back to Top
Q. Does this information apply to
Selective Estrogen Receptor Modulators (SERMS) or phytoestrogens?
A. These preparations were not studied in the WHI
Hormone Program, and therefore, we cannot make any conclusions about the risks
or benefits of SERMs, such as raloxifene (Evista®) or tamoxifen
(Nolvadex®) or phytoestrogens.
Back to Top
Q. How does this information affect my decision to
use HT for relief from hot flashes, sleep problems and mood swings?
A. The WHI and the observational studies on the risk
of ovarian cancer were long-term studies which were not meant to address the
shorter-term use of HT. Thus, the information from these studies should be
used by women considering use of HT for longer than 3 or 4 years.
Back to Top
|
 |
