About 75 percent of the women were white, 15 percent black, and 6 percent Hispanic. Most of the women were overweight and about 8 percent had diabetes. About 35 percent of the women had used hormone therapy in the past and about 13 percent were current users at the time they enrolled in the study.
The women were randomized to two groupsone received 0.625 mg/day of conjugated equine estrogens (Premarin) and the other a placebo. Premarin and the placebo were supplied by Wyeth-Ayerst Research.
The women were followed for an average of 6.8 years. They visited their clinic at least once a year, and had annual mammograms and clinical breast exams. The study was carefully monitored by an independent Data and Safety Monitoring Board (DSMB). The NIH made the decision at the beginning of February 2004 to stop the study drugs. The JAMA article includes data collected through February 2004.
For every 10,000 women each year, on average, estrogen-alone use compared to placebo resulted in:
The results above were not affected by race or ethnicity, or body mass index (BMI).
Another WHI hormone study, the estrogen-plus-progestin trial, was also stopped early. It was halted in July 2002 after 5.6 years of followup because of an increased risk of breast cancer and because the increased risks of breast cancer, coronary heart disease, stroke, and blood clots outweighed the benefits of a reduced risk of hip fracture and colorectal cancer.
The combined hormone therapy study involved 16, 608 participants, who were randomly assigned to receive either a daily intake of 0.625
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13-Apr-2004