Hormones found to raise stroke risk whatever the age

By Andrew Stern

CHICAGO (Reuters) - Middle-aged women who take hormone replacement therapy to ease menopausal symptoms increase their risk of stroke, researchers said on Monday.

But the overall risk of stroke is low for women in their early 50s just entering menopause and the heightened risk may be minimal if they follow recommendations to take lower doses of the hormones for the shortest possible time.

Using data from 121,700 female nurses participating in the Nurses' Health Study, which began in 1976, researchers found women taking estrogen had a 39 percent increased risk of stroke compared to women who did not take the hormone.

Women taking an estrogen-progestin combination to protect against ovarian cancer had a 27 percent higher risk of stroke.

There were 360 strokes among women who did not take hormone therapy and 414 strokes among those who did.

The percentage increase in stroke risk was similar for women regardless of whether they were in their early 50s and newly menopausal, or older. But because the starting point for stroke risk among the younger women was lower -- 3.8 strokes per 10,000 women per year -- the percentage increase represented fewer additional cases of stroke.

"It added to up to two more cases of stroke per 10,000 women per year taking hormone therapy," Dr. JoAnn Manson of Harvard Medical School, who worked on the study, said in a telephone interview.

"And the risk could be further minimized by using lower doses of estrogen and limiting duration to only a few years," she said.