News - Hypertension Week of June 1, 2003/ Vol. 2 No. 22

Study: Hormone Replacement Therapy Raises Stroke Risk

Healthy older women who take combination hormone replacement therapy have a higher risk of suffering a stroke, according to a study reported in the May 28 issue of the Journal of the American Medical Association.

The study of 16,608 postmenopausal women between the ages of 50 and 79 suggests that those taking estrogen plus progestin were 31 percent more likely to suffer a stroke than those taking a placebo. Of those studied, 151 patients taking hormones had strokes, compared with 107 in the placebo group.

Almost 80 percent of strokes were ischemic, characterized by blockage of an artery in the brain. The hormone therapy group had a 44 percent increased risk for ischemic stroke compared to those taking a placebo. The risk for hemorrhagic stroke, characterized by bleeding in the brain, did not significantly differ among the two groups studied.

The study was part of the Women's Health Initiative, which was halted last July after it was concluded that the overall risks of taking hormone replacement therapy outweighed the benefits. The researchers said their findings expand what is already known about the health hazards of hormone replacement therapy.

Study co-author Dr. W. Jerry Mysiw, of Ohio State University Medical Center, said the study does not address the issue of short-term hormone use for symptoms in the transition phase leading up to menopause and beyond.

"Defining exactly what could be considered safe short-term use is problematic," Mysiw said. "What we do know is the excess risk for stroke became apparent by the second year of combined hormone use."

The study drug and placebo were supplied by Wyeth-Ayerst Research Laboratories, manufacturer of Prempro, the brand name of the combined estrogen and progestin therapy. The study was funded by the National Heart, Lung, and Blood Institute.

Other sources: Ohio State University