Anorexia nervosa (AN), a state of chronic nutritional deprivation, is characterized by GH resistance with elevated GH levels and decreased levels of IGF-I. The effects of supraphysiological recombinant human GH (rhGH) on GH resistance in AN are not currently known.
The aim was to investigate whether supraphysiological rhGH increases IGF-I levels in AN.
We conducted a randomized, placebo-controlled study in a Clinical Research Center.
We studied 21 women with AN, 10 (mean age, 28 ± 2.1 yr) treated with rhGH and 11 (mean age, 29.2 ± 2.6 yr) treated with placebo.
rhGH (mean maximum daily dose, 1.4 ± 0.12 mg/d) or placebo was administered to patients for 12 wk.
IGF-I, N-terminal propeptide of type 1 procollagen, type I collagen C-telopeptide, glucose, and insulin levels were measured at wk 0, 1, 2, 3, 4, 8, and 12; C-terminal propeptide of type 1 procollagen, leptin, and free fatty acid levels were measured at wk 0 and 12. Body composition, including total fat and lean mass, was measured by dual-energy x-ray absorptiometry at wk 0 and 12.
IGF-I levels did not differ between the groups at baseline or after treatment (median after 12 wk-rhGH, 124 ng/ml, interquartile range, 94.5, 170.3; vs. placebo, 85.5 ng/ml, interquartile range, 62, 139; P = 0.3). Similarly, changes in glucose, insulin, free fatty acids, and bone markers did not differ between the groups. Total fat mass and percentage fat mass (rhGH, -2.5 ± 0.6%, vs. placebo, 2.2 ± 1.1%; P = 0.004) decreased significantly in the rhGH group compared to placebo despite comparable weight.
Supraphysiological rhGH administration decreases fat mass in AN without increasing IGF-I levels, supporting the role of GH as a mediator of lipolysis independent of IGF-I.