Menopausal HRT Does Not Prevent Chronic Disease

Researchers have carried out an extended post-intervention follow-up of the 2 Women’s Health Initiative (WHI) trials in order to investigate the effects of menopausal hormone therapy on chronic disease. JoAnn E. Manson, M.D., Dr.P.H., of Brigham and Women's Hospital, Boston, and colleagues examined data from 27,347 postmenopausal women, ages 50 through 79 years, who were enrolled at 40 US centers in 1993. Women with an intact uterus received conjugated equine estrogens (CEE) plus medroxyprogesterone acetate (MPA) or placebo . Whereas women with prior hysterectomy received CEE alone or placebo. The intervention lasted an average of 5.6-years in the CEE plus MPA trial, and 7.2-years in the CEE alone trial, with 6-8 additional years of follow-up until September 30, 2010. Results showed that the risks of CEE+MPA during intervention outweighed the benefits. Postintervention, most risks and benefits had dissipated, although some elevation in breast cancer risk persisted during follow-up. For CEE, the benefits and risks during the intervention phase were more balanced, although analysis of postintervention date revealed a significant decrease in breast cancer risk. Neither regimen affected all-cause mortality. The authors concluded: "In summary, current WHI findings based on results from the intervention, postintervention, and cumulative posttrial stopping phases do not support the use of either estrogen-progestin or estrogen alone for chronic disease prevention."