The Women's Health Initiative (WHI) trial of estrogen plus progestin to prevent heart disease in women, involved 1,100 Iowa women between the ages of 50 and 70. The trial was stopped in 2002, five years into the eight-year study, after initial results showed increased health risks outweighed any benefits.
Robert Wallace, MS, MD, co-author of the study and a professor of epidemiology at The University of Iowa College of Public Health, talks about a follow-up study showing women involved in the WHI trial may actually have an increased risk of developing other illnesses:
What does the new Women's Health Initiative trial report conclude about women taking estrogen plus progestin to prevent heart disease and other illnesses?
Let me first begin with a little bit of history. This trial involved around 20,000 women and there were a number of Iowa participants who gave a lot of their time and effort to this particular study.
In the early 1990s was that there was some tentative evidence that estrogen plus progestin was associated with protection of heart disease. We wanted to do the trial to show what we would gain from this. In the mid-1990s, we started the hormone therapy trial and we stopped it in the summer of 2002, earlier than planned because our trial participants who were on the active drug were getting more heart disease, more breast cancer, more stroke, and more blood clots. So we felt ethically obliged time to stop the study.
Since that time, we've been monitoring their health and that's the basis for the report that just came out in the Journal of the American Medical Association this week.
That report suggests some good news and some not so good news. So the good news is that the heart disease excess that we saw on women taking the medication—that is the progestin and estrogen—heart disease rates actually dropped and there was no difference between those who were on placebo and those who were taking the active drug. The excess heart disease we saw went away and actually went away pretty quickly.
The not so good news was that breast cancer rates, which were about 25 percent, increased in women taking the hormone therapy and continued to stay up even though they stopped the therapy. That is unfortunate and we're continuing to follow these women.
There were other changes in the study that we noticed. The protection from fractures that we found—particularly hip fracture—disappeared when the drug was stopped. There was protection from colon cancer—that protective effect also disappeared when we stopped the therapy. It was the continued increase in cancer rates, particularly the increase in breast cancer, that is important to us.
Why did you and your colleagues want to continue to study the women involved in the WHI trial?
There was every reason to believe that the effects caused by the medication, both good and bad, would continue into the future to some extent, and we owed it to our participants, as well as women everywhere, to better understand and to provide more information about what the lingering effects, if any, of using hormonal therapy might be. So we have done, I think, a very good job of following up with our participants.
How was follow-up done with the women involved in the study?
We talk to our participants every year, mostly by phone and mail, and ask them about the diseases that are of interest to us and they report them to us. We ask them to provide their medical records and we review their medical records to be certain that these events are correct. Then we tally them up and we continue to do that even to this day.
What is the recommendation for the women involved in the Women Health Initiative today?
Because there were lingering effects of hormone therapy in this trial, I think the important thing is to discuss all of this with one's doctor. Since there was a little bit of stroke excess that remained, there was a little bit of blood clot excess that remained, and of course the breast cancer problems, we think women who have been on this particular drug should have all of the appropriate recommended preventive interventions that are correct for women above the age of 50 and women who are post-menopausal. That would include:
- Having an annual mammogram that would include
- Investigation of cardiovascular risk factors
- All of the other age-appropriate activities
One should have a colonoscopy every five to 10 years. One should be concerned about osteoporosis, and particularly again about breast health because of what we found.
What about other women who may have been prescribed estrogen OR progestin (not the combination of both) by their physician – is there reason for them to believe they are at an increased risk?
There are not many post-menopausal women who were given progestin, but there are a number of women, including those who were in a separate trial we did, who received estrogen alone. The findings of the trial were published three or four years ago and are well-known to the medical profession. We are in the process of preparing for publication the three-year experience after estrogen-alone the trial was stopped. That will be coming out soon and we will provide the information to our participants, to the medical community, and to women in general.
If someone wanted to find out more about the increased risk after ending estrogen-plus-progestin therapy, where are your study results published?
Our current study, and that's the best place to start, is at the Journal of the American Medical Association. |
