Body fat distribution and body composition during GnRH agonist therapy.

Abstract

To identify the effects of GnRH agonist therapy on body composition (lean and fat mass components) and body fat distribution. Fifteen women with uterine leiomyomas were given a GnRH agonist (leuprorelin acetate, 3.75 mg) monthly for 4 months. Weight, height, and body mass index (BMI, weight/height) were recorded. Regional and total body composition, trunk-leg fat ratio, bone mineral density of the lumbar spine (L2-L4), and total body were assessed by whole-body scanning with dual-energy x-ray absorptiometry before and after treatment. Uterine volume was measured by transabdominal ultrasonography. The mean (+/- standard deviation [SD]) lean mass of total body, trunk, and leg decreased significantly (36.3 +/- 4.9 to 35.4 +/- 4.4 kg, P <.01; 18.8 +/- 2.8 to 18.1 +/- 2.8 kg, P <.05; and 11.4 +/- 1.8 to 11.1 +/- 1.6 kg, P <.05; respectively), whereas body fat mass, percentage of body fat, and trunk fat mass increased significantly (20.8 +/- 4.8 to 21.8 +/- 4.6 kg, P <.01; 34.9 +/- 5.9 to 36.5 +/- 5.2%, P <.01; and 8.6 +/- 3.0 to 9.3 +/- 3.0 kg, P <.01; respectively). Trunk-leg fat ratio increased significantly (1.03 +/- 0.32 to 1.12 +/- 0.33, P <.05). Weight, BMI, arm tissue composition (lean and fat mass components), and leg fat mass did not change during 4 months of GnRH agonist therapy. Bone mineral density and uterine volume decreased significantly. Hypogonadism by GnRH agonist therapy induces lean mass loss, increased adiposity overall, and upper body fat accumulation.