Cardiovascular Disease Outcomes During 6.8 Years of Hormone Therapy

To examine the effect of long-term postmenopausal hormone therapy on common noncardiovascular disease outcomes. DESIGN AND SETTING: Randomized, blinded, placebo-controlled trial of 4.1 years' duration (HERS) and subsequent open-label observational follow-up for 2.7 years (HERS II), carried out between 1993 and 2000 in outpatient and community settings at 20 US clinical centers.

A total of 2763 postmenopausal women with coronary disease and average age of 67 years at enrollment in HERS; 2321 women (93% of those surviving) consented to follow-up in HERS II. INTERVENTION: Participants were randomly assigned to receive 0.625 mg/d of conjugated estrogens plus 2.5 mg of medroxyprogesterone acetate (n = 1380) or placebo (n = 1383) during HERS; open-label hormone therapy was prescribed at personal physicians' discretion during HERS II. The proportions with at least 80% adherence to hormones declined from 81% (year 1) to 45% (year 6) in the hormone group and increased from 0% (year 1) to 8% (year 6) in the placebo group. MAIN OUTCOME MEASURES: Thromboembolic events, biliary tract surgery, cancer, fracture, and total mortality.