(SEATTLE) -- In 2004, the Women's Health Initiative Estrogen-Only Trial was stopped one year early because of an increased risk of stroke and no overall health benefit for the postmenopausal women who had hysterectomies taking the medication. A new long-term study continued following many of the women after they stopped the estrogen and finds that their age was associated with certain ongoing health risks and benefits long after taking the last pill.
Dr. Andrea La Croix, from Fred Hutchinson Cancer Research Center in Seattle, and co-authors compared the on-going health risks and benefits in women who took the estrogen for an average of six years then stopping and those who did not. Follow up for most of the women lasted almost 11 years. "For heart disease overall we found no difference either during the intervention at the end of the intervention or at the end of this longer- term follow up period no difference between the estrogen group and the group of women who took a placebo pill," explained La Croix.
The study appears in this week's JAMA, Journal of the American Medical Association and researchers say those results differ by age group. According to La Croix, "women in their 50s taking estrogen had 12 fewer heart attacks per 10 thousand women over a year's time and the women in their 70s had 16 extra heart attacks, so the effect of estrogen on heart disease differed significantly by age."
"For breast cancer a woman's age had no effect on their risk, the risk of breast cancer was reduced regardless of age. Hip fracture rates also reduced while on the medication but that changed after women stopped," according to La Croix. Rates of hip fracture in the treated group started to rise and move toward the rate in the placebo group so that by the end of the 10.7 years of follow up the rates were about equivalent.
Researchers say this new information can now be used by women to help them and their physicians make better informed decisions on whether to start this medication and just how long they should take it.
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