Hormone Replacement Therapy – What Does the Research Say?
A recent study by the Women’s Health Initiative (WHI), found that the risks of HRT outweigh the benefits. The WHI found that Hormone Replacement Therapy (HRT) drugs caused increases in breast cancer, heart attacks, strokes, and blood clots. The risk to an individual woman may be small, but the number of cases occurring in the population at large is significant. The study concludes that the risks outweigh the drugs’ actual benefits. Benefits include a small decrease in hip fractures and a decrease in cases of colorectal cancer.
The WHI study was released four years earlier than expected because of researchers’ concerns. The WHI was established in 1991 by the government to address the most common causes of death, disability and impaired quality of life in postmenopausal women. It is the first-ever long-term randomized controlled clinical trial (considered the gold standard by medical researchers) of hormone replacement therapy.
The Women’s Health Initiative is a 15-year multimillion-dollar endeavor, and one of the largest US prevention studies of its kind. The study was designed to look at the effects not only of HRT, but also diet modification and vitamin and mineral supplements. Some 67,000 women from across the country, ranging in age from 50 to 79, are participating in the WHI clinical trials. In addition to those women, the study is also following the medical history and health habits of an additional 100,000 women to examine the relationship between lifestyle, health and risk factors with specific disease outcomes. Final results are due out in 2006.
One researcher states, “The breast cancer risks for women on the combined estrogen-progestin therapy are similar to risks that have been found in other studies,” although the cardiovascular findings were not anticipated. “A decreased risk of coronary heart disease had been hypothesized for women on active hormone replacement therapy, so the finding of slightly greater risks for women on the active hormone replacement therapy was unexpected.” In summary, the health risks for women taking combined estrogen plus progestin therapy were found to outweigh the benefits. The trial was actually stopped due to the risk-benefit ratio, as indicated by a global indicator of overall risk, which was unfavorable and the breast cancer risks crossed what were predetermined safety boundaries.”
Actually, early problems associated with heart disease and strokes were suggested several years ago, whereupon women in the study were informed about previous studies. The breast cancer risks have also been suspect. The magnitude and numbers of risk seem to be the same today as they were then.”
It is true that the risk is relatively small for individual women, and the WHI results tell us that during one year among 10,000 postmenopausal women with a uterus, (as opposed to those who have had their uterus removed) and who are taking estrogen plus progestin, eight more will have a stroke, and 18 more will have blood clots, including eight with blood clots in the lungs, than will a similar group of 10,000 women not taking these hormones. This is a relatively small annual increase in risk for an individual woman,” said the acting director of the WHI.
Update: the WHI has now continued with the estrogen-only portion of the study. Scientists have known that progestin can act to influence breast growth and development while reducing the risk of uterine cancer. Actually, an article in the January 26, 2000 Journal of the American Medical Association reported that researchers at the National Cancer Institute had found that women who are current or recent users of combined estrogen and progestin had a higher relative risk of breast cancer than women who only take estrogen.
Although these early findings from the WHI raise some cautions and pose some questions, “The most important thing about what we know is that women need to understand the risks and benefits of hormone replacement therapy so they can make informed choices. Advice: talk to your physician or health care provider.