Obesity and sarcopenia after menopause are reversed by sex hormone replacement therapy

Objective: Menopause is linked to an increase in fat mass and a decrease in lean mass exceeding age-related changes, zn possibly related to reduced ou tput of ovarian steroids. In this study we examined the effect of combined postmenopausal hormone replacement therapy (HRT) on the total and regional distribution of fat and lean body mass. Research Methods and Procedures: Sixteen healthy postmenopausal women (age: 55 +/- 3 years) were studied in a placebo-controlled, crossover study and were randomized to 17 beta estradiol plus cyclic norethisterone acetate (HR T) or placebo in two 12-week periods separated by a 3-month washout. Total and regional body composition was measured by DXA at baseline and in the 10 th treatment week in both periods. Changes were compared by a paired Studen t's t test. Results: The change in body weight during HRT was equal to the change durin g placebo (-24.6 g vs. -164 g, p 0.42), but relative fat mass was significa ntly reduced (-0.5% vs. +1.24%, p < 0.01). During HRT, compared with during placebo, lean body mass increased (+347 vs. -996 g, p < 0.01) and total fa t mass decreased (-400 g vs. + 836 g, p = 0.06). Total bone mineral content increased (+28.9 vs. -4.4 g, p = 0.04) and abdominal fat decreased (-185 g vs. +253 g, p = 0.04) during HRT compared with placebo. Discussion: HRT is linked to the reversal of both menopause-related obesity and loss of lean mass, without overall change in body weight. The increase in lean body mass during HRT is likely explained by muscle anabolism, whic h in turn, prevents disease in the elderly.