Estrogen Trial Shows More Stroke Risk
Tue 2 March, 2004 18:57
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WASHINGTON (Reuters) - The National Institutes of Health said on Tuesday it had stopped a trial of women taking estrogen replacement therapy after finding the pills not only failed to reduce the risk of heart disease but raised the possibility of a stroke.

It was the second large trial of hormone replacement therapy to have been halted in two years. In July 2002, women taking estrogen and progestin were told to stop because of the risk of heart attack, stroke and some forms of cancer.

But officials stressed that women taking HRT should not panic, because the risk of stroke had already been noted years before. "This is not an emergency," Dr. Barbara Alving, director of the trial, called the Women's Health Initiative, told reporters.

"Currently the (Food and Drug Administration) advises women using hormone therapy to use the lowest doses for the shortest period of time."

The FDA said many women who take HRT to reduce the worse symptoms of menopause such as hot flashes and sexual effects could still consider HRT, with a doctor's advice.

The estrogen-only trial was a separate arm of the WHI that looked at women over 50 who had hysterectomies and were taking Wyeth Co's WYE.N Premarin, made from the urine of pregnant mares. Already about half the 11,000 women in the trial had dropped out, the researchers said.

The women had received letters in 2000 and 2002 warning them of the stroke risk. The NIH decided to stop the trial about a year early after getting enough information to decide that the benefits of estrogen did not outweigh the stroke risk.


Some advisers disagreed, but the decision was finally made "at the top level" of the NIH to stop the trial and analyze the data. Details on the effects of estrogen-only therapy will be published in a major medical journal in April, Alving said.

She said the findings would not apply to young women who take estrogen after having hysterectomies. "The mean age of these women is about 70 years of age. We are talking about women of a certain age, a certain population," Alving said.

Dr. Jacques Rossouw, WHI project officer, said the finding would be presumed to apply to all HRT, no matter what the formulation or dose.

Alving said both trials clearly showed that HRT can help prevent osteoporosis. Unlike the estrogen plus progestin trial, estrogen alone did not increase the risk of breast cancer.

Menopausal women and their doctors were shocked when the Women's Health Initiative showed in 2002 that hormone replacement therapy did not, as had widely been believed, prevent heart disease or memory loss.

Wyeth, which makes both drugs used in the WHI, said 6.4 million women were taking Premarin before the 2002 announcement and 3.4 million were taking the estrogen-progestin combination called Prempro.

Now the company estimates 4 million women are taking Premarin and 300,000 are taking Prempro.

Deutsche Banc stock analyst Barbara Ryan said combined global sales of the drugs will likely fall to $1 billion in 2004 from $1.3 billion last year not because of the news but because of the older concerns.

Wyeth said it now has lower-dose formulations of estrogen, although there is no data to show these are any safer.

Dr. Victoria Kusiak, vice president of global medical affairs at Wyeth, said the company had no plans to do any trials of the lower doses, saying they would be difficult to do. Kusiak and Alving agreed that older women need to find other ways to reduce their risk of heart disease, such as exercising, losing weight and eating a healthy diet.