Physical effects of growth hormone treatment in children with Prader-Willisyndrome

A randomized, controlled study of 54 children (age, 4-16 years) with Prader -Willi syndrome was conducted to assess the potential beneficial effects of growth hormone (GH) treatment. After observation for 6 months, the childre n were randomized to receive GH at a dose of 3 IU/m(2)/day (1 mg/m(2)/day) (n = 35) or no intervention (n = 19). The effects of GN treatment on linear growth, body composition, muscle strength, pulmonary function and resting energy expenditure were assessed. The levels of GH secreted in response to clonidine stimulation were universally low, and mean (+/- SD) insulin-like growth factor I SDS was -1.2 +/- 0.8 pretreatment. In children treated for 1 year, mean height velocity SDS significantly increased from -1.0 +/- 2.5 to 4.6 +/- 2.9 (p < 0.0001), mean percentage body fat decreased from 46.3 /- 8.4% to 38.4 +/- 10.7% (p < 0.001), mean lean body mass increased from 2 0.5 +/- 6.3 kg to 25.6 +/- 4.3 kg (p < 0.01) and respiratory muscle functio n and physical strength improved. Mean respiratory quotients significantly decreased from 0.81 to 0.77 (p < 0.001); however, resting energy expenditur e did not change. Therefore, GH therapy appears to reduce some of thr physi cal disabilities experienced by children with Prader-Willi syndrome.