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Dressed informally in a button-down shirt and slacks, breast surgeon Susan M. Love bounds onto the podium and cheerfully confides to her audience that she has just removed her suit jacket in response to a “hot flash.”
Love, author of the best-selling Dr. Susan Love's Hormone Book and an adjunct professor at the University of Southern California, has recently gone on a campaign to counter the prevailing wisdom that women should routinely take hormones after menopause.
“Just as the baby-boomers are hitting menopause, it's become a disease - estrogen deficiency disease,” she told 600 breast cancer activists at the National Breast Cancer Coalition conference in Washington, D.C., in May. But Love ridicules that idea, suggesting instead that evolution has programmed a shifting-down in hormone levels once women reach an age when high hormone levels are no longer necessary for reproduction. She tells her audience she's worried by the evidence that hormones increase the risk of breast cancer and isn't convinced by the studies showing it reduces the risk of heart disease.
Love's contention has plunged her into a controversy over the pros and cons of hormone replacement therapy. The largest study done to date, published in June, found that the chance of dying was 37 percent lower among women who were using hormones than among women who did not, primarily because of fewer deaths from heart disease. However, the mortality benefit dropped to 20 percent after 10 or more years of hormone use as the women's risk of breast cancer mortality rose. The study of 60,000 post-menopausal women is the latest report from the Nurses' Health Study, which has followed more than 100,000 female registered nurses on their health-related behavior starting in 1976.
For women with family histories of breast cancer or who are otherwise at higher risk for breast cancer, the implications of the new study are more complicated. The study found a 43 percent increase in deaths from breast cancer among women who had used the hormones for 10 or more years. A counterintuitive finding is that short-term hormone users had a reduced risk of death from breast cancer.
Francine Grodstein, an epidemiologist at Brigham and Women's Hospital in Boston who directed the study, suspects that's because those women who took hormones for a few years were health-conscious women who were likely to see their doctors often, were diagnosed with breast cancer at an early, more curable stage and were taken off hormones as soon as they were diagnosed. The main hormone given to menopausal women, estrogen, is thought to promote breast cancer.
In a surprising finding, women with a family history of breast cancer had the same reduction in overall mortality risk (from all causes) as other women in the study, once the benefits of reduced heart disease deaths were factored in.
But Grodstein cautions that this study looked only at the risk of dying, not the risk of getting a disease like breast cancer. An earlier study she published in The New England Journal of Medicine found an increase in the occurrence of breast cancer starting after five years of hormone use.
“There's a difference between having a disease and dying from it. This [study] doesn't mean women with a family history should be told to take hormones,” she says. “Having breast cancer and not dying of it is not an acceptable option.”
As for other women, Grodstein says, “Overall, in terms of mortality, they're likely to get a benefit [from taking hormones], particularly if they have risk factors for heart disease” like smoking or high cholesterol levels.
Since the mid-1960s, doctors have prescribed the female hormone estrogen to relieve some of the temporary symptoms that accompany the onset of menopause - hot flashes, headaches, vaginal dryness, sleeplessness and mood swings among them. In response to research suggesting that estrogen also protects against heart disease and the bone-thinning disease osteoporosis, doctors have increasingly distributed the hormone for its preventive properties.
Starting in 1975, studies have shown that estrogen given alone increases the risk of uterine cancer. The increased risk can be countered by giving estrogen in combination with progestin - a synthetic form of the natural hormone progesterone.
But what worries many women is the possibility that the hormones will increase their risk of breast cancer. The evidence on this issue is conflicting, with some studies showing no effect or even decreased effect on breast cancer.
However, one of the most publicized studies - a 1995 report from the Nurses' Health Study - found an increased incidence of breast cancer among women who take estrogen or estrogen-progestin combinations.
It's these findings that Love, who has treated thousands of breast cancer patients, focuses on. Love argues that the medical community is underestimating the risk of breast cancer and overestimating the benefits for heart disease.
Love observes that in studies so far, women who took hormones tended to be higher-income, thinner and better educated than those who did not. As a result, it's not clear if healthier women are taking hormones or the hormones made them healthy, she says. Grodstein contends this is less of a concern in the Nurses' Health Study, since nurses tend to have similar knowledge when it comes to health.
Love's most powerful argument is that breast cancer is more of a concern for younger women than heart disease or osteoporosis. The average age for death from breast cancer among women in the U.S. is 68; for heart disease it's 79.3. The average age at which women get their first hip fracture because of osteoporosis is 79, according to Love.
But in a recent article in The New Yorker, science writer Malcolm Gladwell said one statistic that is central to Love's argument is dead wrong. In her book on hormones, she writes that among women younger than age 75, there are actually three times as many deaths from breast cancer as there are from heart disease. In fact, the figures from the government's National Center for Health Statistics shows the reverse, Gladwell notes. About three times as many women in that age bracket die from heart disease as from breast cancer.
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