Differential effects of oral estrogen versus oral estrogen-androgen replacement therapy on body composition in postmenopausal women.

Abstract

Menopause is associated with decreased lean body mass and increased fat due to aging and declining hormone secretion. Estrogens or estrogen-progestins have been used to alleviate vasomotor symptoms. However, estrogen-androgen (E/A) therapy is also used for vasomotor symptom relief and has been shown to increase lean body mass while decreasing fat mass. The objective of this 16-wk, double-blind, randomized, parallel group clinical trial was to compare esterified estrogen plus methyltestosterone (1.25 mg estrogen + 2.5 mg methyltestosterone/d; E/A group) vs. esterified estrogen alone (1.25 mg/d; E group) on body composition. Forty postmenopausal women (mean age, 57 yr) participated. Compared with estrogen treatment alone, women in the E/A group increased their total lean body mass and reduced their percentage fat for all body parts (P < 0.05). After E/A treatment, there were statistically significant increases in lean body mass by 1.232 kg [0.181 +/- 0.004, 0.81 +/- 0.057, and 0.24 +/- 0.009 kg in the upper body (P = 0.021), trunk (P = 0.001), and lower body (P = 0.047), respectively]. In the E group, the increase was 0.31 +/- 0.004, 0.021 +/- 0.03, and 0.056 +/- 0.05 kg in the upper body, trunk, and lower body, respectively. In the E/A group, body fat was reduced by 0.90 kg (P = 0.18 for the trunk only), and percentage body fat declined by 7.4% (P < or = 0.05 for all body parts). Lower body strength increased by 23.1 kg (51 lb) in the E/A group vs. only 11 kg (24.25 lb) in the E group (P = 0.002 between groups). A statistically significant increase in weight (2.7 +/- 5.1 vs. 0.1 +/- 4.6 lb; P < 0.05) was observed in the E/A group compared with the E group. When subjects were given self-reporting questionnaires, more improvement was noted in sexual functioning and quality of life in the E/A group when compared with patients receiving E alone. There were no noteworthy side effects. In conclusion, E/A replacement therapy can improve body composition, lower-body muscle strength, quality of life, and sexual functioning in postmenopausal women.