Timing, Dosage of HRT Affect Chances of Heart Trouble

Estrogen taken via patch (on the skin) or gel (in the vagina) reduced the risk of heart attack by 38 percent and 44 percent, respectively.

"Overall biological evidence suggests the findings are plausible," Lokkegaard said. "But the finding of significant lower risk among women using vaginal estrogen was very surprising and needs to be investigated further before clinical recommendations can be given."

The results were essentially similar to those from the Women's Health Initiative.

However, one expert added a caveat.

"We have learned from observational data in the past that it is not an appropriate scientific approach to draw conclusions about the benefits or risks of hormone therapy in women," said Dr. Lori Mosca, director of preventive cardiology at New York-Presbyterian Hospital/Columbia University Medical Center and founder and director of the Columbia Center for Heart Disease Prevention in New York City. "These data are interesting, but in no way definitive," Mosca said.

More information

The National Heart, Lung, and Blood Institute has more on the original findings of the Women's Health Initiative.

SOURCES: Ellen Lokkegaard, M.D., gynecologist, Rigshospitalet, Copenhagen, Denmark; Lori Mosca, M.D., director, preventive cardiology, New York-Presbyterian Hospital/Columbia University Medical Center, and founder and director, Columbia Center for Heart Disease Prevention, New York City; Oct. 1, 2008,European Heart Journal