National study halted since health risks exceed benefits in postmenopausal women on estrogen.

2002 JUL 25 - (NewsRx.com & NewsRx.net) -- Researchers nationwide have halted the part of a 40-center study that involved trying to determine the risks versus the benefits of healthy postmenopausal women taking the hormones estrogen and progestin.

That's because after 5 years of data collection, the study clearly showed the risks outweighed the benefits, scientists said. Taking the combination appears to boost the chance of developing breast cancer somewhat and does not lead to the anticipated benefits in preventing heart attacks and strokes.

The National Heart, Lung and Blood Institute sponsors the continuing, larger project, which is known as the Women's Health Initiative. Institute officials held a news conference at the National Press Club in Washington, DC, July 9, 2002, to announce their action. A paper describing the findings in detail will appeared online in JAMA-Express also on July 9 and in the July 17 issue of the Journal of the American Medical Association.

"This was a randomized, placebo-controlled trial of estrogen plus progestin in more than 16,000 women with a uterus," said Dr. Gerardo Heiss, professor of epidemiology at the University of North Carolina (UNC) at Chapel Hill School of Public Health. "The estrogen plus progestin trial was stopped early - after 5.2 years - because of a 26% increased risk for breast cancer and also a lack of overall benefit. As soon as the increased risk for breast cancer was established, the independent data and safety monitoring board halted the study."

A second trial of estrogen alone in 11,000 women who have had hysterectomies continues unchanged, said Heiss, a member of the Women's Health Initiative steering committee. "We wish to express our appreciation and thanks to the 16,608 women who participated in this WHI study. They are true pioneers and have made an important contribution in answering a very important question for millions of women.

"Because of them, we now know the balance of risks and benefits of the estrogen plus progestin treatment most commonly prescribed in the United States for postmenopausal women who have a uterus," he said. "The bottom line is that estrogen plus progestin is not a viable option to prevent chronic disease."

Other UNC faculty, all with the schools of medicine or public health, involved in the research are Drs. Ellen Wells, assistant professor of obstetrics and gynecology; David Ontjes and Carla Sueta, professor and associate professor, respectively, of medicine; Kathy Light, professor of psychiatry; Pamela Haines, associate professor of nutrition; and Barbara Hulka, professor of epidemiology emeritus.