RAY SUAREZ: A new study in today's "Journal of the American Medical Association" raises questions about hormone replacement therapies used by millions of women. Here to explain is Health Correspondent Susan Dentzer. Our health unit is a partnership with the Henry J. Kaiser Family Foundation. Now, Susan, 20 million or more American women take one or both of the main hormone-replacement therapies. So this is certainly going to get a lot of attention. Why is this a popular drug therapy?
SUSAN DENTZER: Well, Ray, hormone-replacement therapy is something that women engage in, in order to replace the normal hormones that disappear with menopause, which is, of course, the cessation of menstruation. So many bodily changes are a function of menopause and the decline of these hormones, estrogen primarily and progesterone, and many women experience some short-term symptoms which can be quite severe, for example, hot flashes, moodiness, some depression, some dryness of the skin, vaginal dryness. Those are very unpleasant symptoms that women obviously want relief from, so they tend to take... many women will tend to take either estrogen replacement only, which was very common in the past, or now more commonly the combined therapy of estrogen, as well as progesterone, which is given because it was detected that there was an increased risk in cancer of the lining of the uterus from taking estrogen only. So now, for women who have not had a hysterectomy, who still have their uteruses, the common form of therapy is this combined therapy. And indeed, as you say, it's very common.
RAY SUAREZ: The women who were being observed were part of a very large study involving breast cancer. What was reported about the hormone-replacement therapy?
SUSAN DENTZER: This study weighted into a very controversial issue. Most researchers would agree that short-term use for the symptoms I described earlier -- two to three years to get through menopause -- is reasonably safe and effective for many women. The controversy has been what are the long-term risks of this use, and do they offset some of the benefits? It has been thought that there are...if you took hormone-replacement therapy over a long period of time, you could reduce your risk of cardiovascular disease, heart disease, heart attack; you could also reduce your risk of osteoporosis, bone fracture and other disabling things.
The question has been: Do you increase your risk of breast cancer such that you offset your risk of these other things? And that's been the issue. What this study did was look back at a study that's been under way for a number of years -- that was under way for a number of years -- of 46,000 women who were being studied in the whole area of breast cancer detection. And it asked these women, in effect, had they been taking hormone-replacement therapy and then tried to make some judgments over what the risks were.
In fact, what the study found was that for women who had used the estrogen-only therapy, there was indeed an increased risk of breast cancer on the order of about 1 percent increased risk per year of use. And for women who had been using the combined form, the estrogen and progesterone form, which is now most common, there was an even greater increased risk of a percent a year.
RAY SUAREZ: But was the sub-sample so small that we can't say definitively this is a bad idea?
SUSAN DENTZER: Indeed, it was in the view of many researchers. It's a controversial area. But if we look... this study, again, applied to 46,000 women. But if you look at the number of women who had had... were treated for this combination therapy for six years or more, it was really only 21 women, and of those 21, six went on to develop breast cancer. So, in fact, this calculation of the increased risk is based on a very small number of women who actually developed breast cancer. It's the reason why many people who look at the study stand back and say, "yes, it squares with some results we were seeing in earlier studies, but we really won't understand the risks of all of this until we see some longer term studies and more scientifically-controlled studies that will be coming out over the next decade."
RAY SUAREZ: Well, often in research projects of this kind, we don't get the definitive answer, but we start asking the right questions, and it points us toward research projects that do ask more narrowly defined questions and maybe get better answers. What does this point us to?
SUSAN DENTZER: This points us to the need to complete the studies that are underway and what's known as the Women's Health Initiative, which is a large study, federally funded study, which is currently comparing for 27,000 women, what the benefits and risks are of using hormone-replacement therapy, versus a placebo, a dummy drug. When those results start to be in after 2005, 2008, we'll know a lot more. The important thing in the meantime, and doctors that I spoke to today were stressing this, is what do you tell women?
What we tell women now on the basis of this perhaps is not much more than we would have told them before the study, it's that, whether or not you should use hormone-replacement therapy over the long term; that is, beyond the two to three years immediately around menopause, depends on lots of things. It depends on your risk for breast cancer in your family, it depends on your weight because a very important aspect of this study also was a finding that these increased risks mainly affected women of normal weight.
When it got to women who were already overweight, they already had a higher risk of breast cancer, and taking hormone-replacement therapy for them didn't increase their risk any more, it appeared, than they had already had. So an important factor is: What's your weight? What's your family history of these cancers? And also, finally, what goals do you want to accomplish by use of long-term hormone replacement therapy? If you're worried about cardiovascular disease, you can quit smoking, adopt a healthy diet, lose weight. If you're worried about osteoporosis, you can also make dietary changes, you can exercise, and also there are drugs available now to treat osteoporosis, which are very effective. So clinicians want to point to women the variations dependent on their own risks, as well as the many other options that are available to them.
RAY SUAREZ: Susan Dentzer, thanks for coming by.
SUSAN DENTZER: Thanks, Ray.