Federal Researchers End Estrogen HRT Study One Year Early
NIH on Tuesday announced that it has ended the portion of the Women's Health Initiative study on the health benefits of estrogen for menopausal women who have had hysterectomies after concluding that the hormone increased the risk of stroke and did not prevent heart attacks, the Washington Post reports. Scientists decided on Feb. 2 to end the study after seven years, about a year ahead of schedule (Brown, Washington Post, 3/3). "The NIH believes that an increased risk of stroke is not acceptable in healthy women in a research study. The NIH has determined that the results would not likely change if the estrogen trial continued to its planned completion in 2005," an NIH statement said. The termination of the study, which involved 10,700 women, comes 18 months after the WHI section on combination estrogen-progestin was halted (McCullough, Philadelphia Inquirer, 3/3). In July 2002, federal health officials ended the study on combination HRT three years early because researchers determined that the treatment may increase the risk of invasive breast cancer, stroke, heart attack and other health problems. Since last year, regulators have required products that contain estrogen to carry warnings that HRT increases the risk of breast cancer, stroke and heart attacks (California Healthline, 12/16/03).
In the estrogen-only study, participants who had undergone hysterectomies were selected because combination HRT therapy was not medically necessary; combination HRT's progestin is added for its protection against estrogen-induced uterine cancer (Mestel, Los Angeles Times, 3/3). The estrogen study included women between 50 and 79 years old who were given either estrogen or a placebo for an average of seven years (Grady, New York Times, 3/3). The average age of the participants was 70 (Szabo, USA Today, 3/3). Of the nearly 11,000 women who initially signed up for the study, about half dropped out after the increased risk of stroke became apparent to researchers and patients were given the opportunity in 2000 and 2001 to end their participation (New York Times, 3/3). NIH officials did not provide detailed results of the estrogen treatment study, saying that their findings would be published in April (Washington Post, 3/3). Findings released early including the following:
- Estrogen-only treatment increased the risk of stroke as much as estrogen-progestin treatment, about eight more strokes per year for every 10,000 women who take HRT.
- Estrogen-only treatment had no effect on heart disease, compared with estrogen-progestin treatment, which increases heart attack risk by 29%.
- Estrogen-only treatment did not increase the risk of breast cancer, while estrogen-progestin use increases that risk by 26%.
- Preliminary data from a related study of women at least 65 years old suggest that, similar to combination hormone therapy, estrogen-only treatment increases the risk of developing some degree of dementia.
- Both estrogen-only and combination therapies decrease the risk of hip fracture from osteoporosis (Neergaard, AP/Newport News Daily Press, 3/2).
According to the Post, the study "disproves for good the theory that replacing the sex hormones that fall steeply after ... menopause would yield an overall benefit to ... health" and "marks the final collapse of a medical and commercial edifice that had been constructed over three decades" (Washington Post, 3/3). Dr. Diana Petitti, director of research for Kaiser Permanente Southern California, said that "as a global preventive agent, as an agent for preventing coronary heart disease, I think both [estrogen-alone and combination HRT] drugs are on terminal life support." However, she added, "Hormone replacement ... still has a place in the treatment of symptoms" of menopause (Los Angeles Times, 3/3). Alan Altman, assistant professor at Harvard Medical School, said that the study's findings were of limited use, saying, "Once again, the study tells us about older women who are well beyond their menopause using a specific product. It tells us nothing about women starting appropriate, individualized hormone therapy right after menopause" (Parker-Pope, Wall Street Journal, 3/3). Dr. James Simon, president of the North American Menopause Society, said, "I think the findings for women are actually quite reassuring, namely that the major issue which women fear, breast cancer, was not increased on estrogen alone" (New York Times, 3/3).
"Another stake has been driven into hopes that long-term hormonal treatment might provide health benefits to postmenopausal women" with the decision by NIH to end the estrogen study, according to a New York Times editorial. The editorial continues that the decision contributes to the "woes that have dogged hormone therapy for the past two years." Although HRT in the past was considered an "anti-aging elixir to ward off chronic illnesses and make women feel more energetic, mentally sharper and more sexually responsive," the results of the estrogen study "give further reason to limit hormone therapy primarily to uses where all agree it is valuable -- short-term treatment to relieve acute symptoms of menopause, like hot flashes and vaginal discomfort." The editorial concludes, "The best advice is to use the lowest dose for the shortest time possible" (New York Times, 3/3).
The following broadcast programs reported on the end of the study:
- CBS' "Early Show": CBS medical correspondent Dr. Emily Senay discusses the study (Senay, "Early Show," CBS, 3/3). The complete transcript and video of the segment in RealPlayer will be available online after the broadcast.
- CBS' "Evening News": The segment includes comments from Alving and Dr. Lawrence Phillips of Emory University (Kaledin, "Evening News," CBS, 3/2). The complete segment is available online in RealPlayer.
- NPR's "All Things Considered": The segment includes comments from Alving and Dr. Isaac Schiff, chief of obstetrics and gynecology at Massachusetts General Hospital (Neighmond, "All Things Considered," NPR, 3/2). The complete segment is available online in RealPlayer.