Abstract 11380: Hormone Replacement Treatment in Early Postmenopausal Women Reduces Cardiovascular Events - A Randomized Controlled Study
Objective: To investigate the long-term effect of hormone replacement therapy (HRT) on cardiovascular outcome.
Methods: From 1990 to 1993, 1006 women were enrolled and randomly allocated to receive either HRT or no treatment in the Danish Osteoporosis Prevention Study (DOPS). The women were healthy, Caucasian, aged 45-58 years, recent postmenopausal (PM) or having perimenopausal symptoms in combination with PM serum FSH values. Hysterectomized women were included if aged 45-52 years, provided PM serum FSH. In the HRT group women with intact uterus was treated with varying cyclic doses of estradiol and norethisterone acetate. Hysterectomized women received 2 mg estradiol/day. After 11 years the randomized study was stopped due to other studies showing an excess risk of breast cancer with HRT, but all patients were followed for up to 16 years. The primary endpoint was a combination of mortality, heart failure and myocardial infarction (MI). Comparison of the 2 randomized groups was tested in an unadjusted Cox model and in an adjusted Cox model with age as a co-variable.
Results: Women were in average 50 years, 7 months PM, body mass index 25, 7% had hypertension. Non-HRT women were 0.47 years older than HRT women. Women in the 2 groups did not differ significantly regarding any other known risk factor. In total, 67 women died, of these 27 in the HRT group and 40 in the non-HRT group. Hazard Ratio (HR): 0.66 (0.41-1.08; p=0.10). 33 women receiving HRT experienced the primary endpoint, and 53 women in the non-HRT group (Fig. 1). HR was 0.61 for women randomized to HRT (p= 0.02). Adjusting for age did not alter results. The observed reduction in cardiovascular events was not opposed by an increase in any cancer or breast cancer (HR: 1.28; p=0.24 and HR: 0.92; p=0.77, respectively)
Conclusion: Women treated with HRT early after menopause have a significantly reduced risk of mortality, heart failure, or MI. There was no difference in prevalence of cancer between groups 16 years after study start.
- © 2011 by American Heart Association, Inc.