They quit cold turkey, and in droves.
Within six months after the nation’s first long-term, large-scale clinical trial of hormone-replacement therapy revealed that the risks of taking estrogen plus progestin outweighed the benefits, an estimated 60 percent of the 6 million U.S. women on that combination treatment stopped taking their pills. The number of women taking just estrogen also fell precipitously, from 8 million to about 5 million.
Researchers halted the estrogen-plus-progestin portion of the trial in July 2002, when it became clear that women taking the combination pills faced increased risks of breast cancer and cardiovascular disease (see Farm Report, September/October 2002). “By and large, most of the women in the study came off [the hormones] with no consequence at all,” says Marcia Stefanick, an associate professor of medicine who chairs the multicenter study’s steering committee and directs the Stanford Center for Research in Disease Prevention.
To understand how women are reacting nationally, the researchers are surveying physicians and tabulating filled prescriptions. “A certain percent of women who stopped have gone back on, because of symptoms, and right now everybody is trying to figure out what is that percent,” says Stefanick, PhD ’82. “We certainly hear about the women who had a bad experience with stopping, and we don’t hear about the women who came off and it was no big deal, so everyone’s getting a biased picture.”
Having analyzed the trial’s five-plus years of data, the investigators are busy turning out papers on the effects of combination therapy on everything from bone density to the incidence of strokes. In August, they reported in the New England Journal of Medicine that estrogen plus progestin increased the risk of heart disease 81 percent in the first year of therapy and 24 percent overall. An ancillary study of dementia in women over 65 was particularly surprising, Stefanick says. “Contrary to what everybody expected, which was that [the emergence of] dementia would be reduced with estrogen and progestin, it was doubled.”
Stefanick says it has been “fascinating to see how quickly the medical community and the public embraced the overthrow of the concept that women should be on hormone therapy after menopause.” They seem, she adds, “to understand the key message that the primary reason to prescribe or take hormones is to relieve intolerable menopausal symptoms, and that [such therapy] should not be initiated or continued for the purpose of preventing heart disease or dementia.”