Health Outcomes After Stopping Conjugated Equine Estrogens Among Postmenopausal Women With Prior Hysterectomy

Abstract

The Women's Health Initiative (WHI) Estrogen-Alone Trial was a double-blind, placebo-controlled, randomized clinical trial evaluating the effects of conjugated equine estrogens (CEE) on chronic disease incidence among postmenopausal women with prior hysterectomy. The trial intervention was stopped 1 year early after a mean of 7.1 years of follow-up because of an increased risk of stroke and little likelihood of altering the balance of risk to benefit by the planned termination date. Analyses of outcomes during the intervention period suggested that treatment effects differed by age; compared with older women, younger women receiving CEE had a lower risk of coronary heart disease (CHD), colorectal cancer, total death, and the global index of chronic diseases.¹ However, the tests for interaction of age with treatment were only statistically significant for colorectal cancer.¹