WHI HT Update--2002
WHI Hormone Program
The WHI Hormone Program is studying two types of hormone
pills. One is estrogen plus progestin in women who had not had a
hysterectomy before joining the WHI. The other is estrogen alone in women who
already had a hysterectomy before joining. This "Update" describes
information about the estrogen-plus-progestin study, which was stopped in July 2002.
Hormone Program Results Reviewed
The WHI Data and Safety Monitoring Board (DSMB) reviews
the health status of women in the Women's Health Initiative every six months. Based on
this regular review, the DSMB in 2002 recommended that:
- Women in the study of estrogen plus progestin stop
their study pills, because the risks exceeded the benefits.
- Women in the study of estrogen alone continue
taking their study pills as before, because it remained uncertain whether the
benefits outweigh the risks. (NOTE: In March 2004, the NIH advised women in the estrogen-alone trial to stop taking their study pills.)
Assessing Risks and Benefits
In trying to understand the overall balance of risks and
benefits of estrogen plus progestin, the DSMB reviewed information on
many health conditions. Earlier "HRT Updates" told you about the effects of
hormones on heart attacks, strokes, and blood clots. Now an important increase
in breast cancer for women on estrogen plus progestin has become clear.
The graph below shows how often certain health events
occurred in women taking estrogen plus progestin (darker bars) and in women
taking placebo or inactive pills (lighter bars). Heart attacks, strokes, blood
clots, and breast cancer occurred in more women on estrogen plus progestin.
Fewer women on these hormones had colorectal cancer and hip fractures. There
were no differences in the number of women who had endometrial cancer or in the
number of deaths.
Graph data in table format.
How many women were affected?
Only 2.5% of women in the estrogen plus progestin study had
these health events. These results tell us that during one year, for every
10,000 women taking estrogen plus progestin, we would expect:
- 7 more women with heart attacks. In other words, 37 women
taking estrogen plus progestin would have heart attacks compared to 30 women
- 8 more women with strokes.
- 8 more women with breast cancer.
- 18 more women with blood clots.
These results also suggest that for every 10,000
women taking estrogen plus progestin, we would expect:
- 6 fewer colorectal cancers.
- 5 fewer hip fractures.
- Fewer fractures in other bones.
In summary, then, more women taking estrogen plus progestin
had a serious health event than did women taking placebo. We conclude that
estrogen plus progestin does not prevent heart disease and is not beneficial
These results do not apply to women who had a
hysterectomy before joining WHI and are participating in the study of estrogen
What does this mean for me?
If you are in the estrogen-plus-progestin Hormone
Program, you should stop taking your study pills. You are in this part of
the program if you had not had a hysterectomy before joining the WHI. We also
ask you to provide us with "Medical History Update" information so that we can
study all the serious health events that occurred up to this point. Also,
please return the "Signature Sheet" with this form. Your clinic staff will let
you know how to return any left-over study pills. You should continue having
your yearly mammograms and WHI clinic exams. Even though you stop your study
pills, your ongoing participation is important because it will help us learn
how these effects change after you stop your study pills.
If you are in the estrogen-alone Hormone Program,
please continue taking your study pills as before and having your yearly
mammograms and WHI clinic exams. Your efforts will help us learn whether the
overall benefits of taking estrogen alone exceed the risks. This question is as
important now as ever. (NOTE: In March 2004, the NIH advised women in the estrogen-alone trial to stop taking their study pills.)
If you are in other WHI programs, everything else
stays the same. Nothing has changed for you. There are many more questions
about women's health that need to be answered. These answers will help women
and their doctors make better decisions about women's health.
How can I find out more?
This update reviews the information available now. You may
find additional details on the World Wide Web (http://www.whi.org/). WHI scientists will also
do more data analyses over the coming weeks and months. As these results become
available, we will inform you through newsletters and updates to the study
Thank you for taking part in this landmark study of
women's health. The time and effort you have given to the WHI has made it
possible to answer one of many important health questions for postmenopausal
women in the United States. We have more work to do and hope that you will join
with us in continuing this effort.