Hormone replacement therapy timing and heart disease
Women who began hormone replacement therapy (HRT) within four years of menopause had about a 30% lower risk of heart disease than did women who never used hormones, said Francine Grodstein, Sc.D., and colleagues at Brigham and Women's Hospital here.
However, when therapy was initiated 10 or more years after menopause there was no significant association with coronary heart disease, the researchers reported in the January issue of the Journal of Women's Health.
"This study helps to untangle some of the confusion about the heart-protective effects of hormone therapy by indicating that the timing of starting hormones relative to a woman's age and onset of menopause plays a key role," said Joann E. Manson, M.D., Dr.P.H., also of Brigham and Women's Hospital, a co-author.
In older women, existing damage to vessels may be the reason HRT does not protect them from heart disease," said researcher Dr. JoAnn E. Manson, the chief of the division of preventive medicine at Brigham and Women's Hospital, in Boston. "If a blood vessel already has advanced atherosclerosis, hormone therapy may be more likely to cause a clot. However, if the blood vessel is open, the increase in clotting risk usually will not translate into a heart event, and some of the benefits may predominate as improvement in cholesterol, improvement in insulin sensitivity and antioxidant effects. Estrogen may actually delay the development of artherosclerosis in those women."
This is welcome news for those newly-menopausal in need of therapy because of troubling menopausal symptoms or osteoporosis. Concerns had been raised about an increased risk of stroke or no heart disease benefit, so women of all ages had stopped taking HRT. Further analysis of these earlier studies indicated that the study participants were older, had never been on HRT, and were already at risk. Still, the study authors cautioned that their results do not yet support hormone therapy for prevention of coronary heart disease.