Hormone study is halted as rising risk recognized

Stroke, breast cancer, heart disease more likely

July 10, 2002|By Jonathan Bor | Jonathan Bor,SUN STAFF

Government scientists have abruptly halted a landmark study of hormone therapy for post-menopausal women, saying it increased rather than lowered the risk of heart disease and stroke and raised the chance of breast cancer.

Although the chances of a woman developing these diseases remained small, five years on the combination estrogen-progestin therapy raised the risk of stroke by 41 percent, heart attack by 29 percent, cardiovascular disease by 22 percent and breast cancer by 26 percent.

In ending the trial three years earlier than planned, researchers said the disappointing results should motivate many of the 6 million women in the United States on long-term therapy to talk to their doctors about stopping.

"The cardiovascular and cancer risks of estrogen plus progestin outweigh any benefits, and a 26 percent increase in breast cancer risk is too high a price to pay even if there were a heart benefit," Dr. Claude Lenfant, director of the National Heart Lung and Blood Institute, said yesterday.

The study adds to the mounting evidence that hormone therapy poses significant risks. It will likely cause many doctors to recommend it only for short-term relief of menopausal symptoms.

A separate study found last week that combination therapy did not prevent heart attacks in women with pre-existing cardiovascular disease and slightly increased their risk of blood clots in the legs and lungs.

Meanwhile, a study on the long-term use of estrogen-only pills by women who have had hysterectomies was allowed to continue because no clear evidence had yet emerged. An estimated 8 million women in the United States take the estrogen-only therapy.

Yesterday's announcement upset the conventional wisdom about disease prevention and sparked a flood of anguished calls to doctors' offices.

"I've probably gotten 40 calls just this morning," said Dr. Steven Adashek, a gynecologist with the Greater Baltimore Medical Center who began scheduling women to come in and discuss what they should do.

"I just need to recalculate people's risk and benefit for staying on this," said Adashek, a longtime advocate of the therapy. "There are a significant number of women who will stop, or should stop."

The study did find a reduction in colon cancer and hip fractures, a frequent outcome of osteoporosis, but researchers said those benefits did not outweigh the risks.

After the announcement, the American College of Obstetrics and Gynecology said it had convened a task force to review the data and quickly come up with clinical recommendations for physicians. ACOG is the leading standard-setting organization for the specialty.

The study, part of the federally funded Women's Health Initiative, involved 16,000 women across the United States who were testing the value of the combined hormones, estrogen and progestin, in preventing heart disease, stroke and other illnesses.

"When we started the study, we did so because we thought it was likely that hormone replacement would prevent heart disease," said Dr. Jacques Rossouw, acting director of the study. "What this has shown is that the opposite is true."

"It truly means that this particular therapy should not be started or continued for the prevention of heart disease."

The study did not assess the therapy for the reduction of menopausal symptoms such as hot flashes, dryness and sleeplessness. Such treatment usually lasts one to five years, in contrast to long-term preventive therapy, which can last decades.

A report from the Women's Health Initiative on the combination therapy is to be published Tuesday in The Journal of the American Medical Association, but the results were released early on the journal's Web site because of their importance.

Women in the study were randomly assigned to receive a daily dose of the combination therapy or a placebo. Participants were enrolled in the study at 40 clinical sites across the country beginning in 1993.

After more than five years, researchers were surprised to find that the therapy increased the risk of strokes, heart attacks and breast cancer.

At the same time, the therapy reduced the risk of colorectal cancer by 37 percent, hip fractures by 33 percent and total fractures by 24 percent. There was no difference in death rates between the two groups.

Among 10,000 women on combination therapy for a year, eight more women will be diagnosed with breast cancer than would expected in a similar group not taking the drugs, according to the study. Also, the drugs would cause seven more heart attacks, eight more strokes and eight blood clots in the lungs.

In some cases, that calculation might actually understate the danger. The risk of breast cancer did not emerge in the first three years, but it became "very clear" after five years - suggesting that the risk might increase over time, Rossouw said.

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