One Year of Growth Hormone Treatment in Adults with Prader-Willi Syndrome Improves Body Composition: Results from a Randomized, Placebo-Controlled Study

Abstract

Prader-Willi syndrome (PWS) is a multisymptomatic disease that shares many similarities with the GH deficiency syndrome, including altered body composition with more body fat than lean body mass. Our objective was to investigate the effect of GH on body composition in adults with PWS. Forty-six adults with PWS were randomized to GH or placebo treatment for 12 months in a double-blind trial. We evaluated change in regional body composition of the abdomen and thigh as measured by computed tomography and change in total body composition as measured by dual-energy x-ray absorptiometry. Forty patients completed the study. Baseline median IGF-I sd score was -0.4. GH treatment increased IGF-I by 125 μg/liter (1.51 sd score), and based upon computed tomography, body composition improved with a decrease in visceral fat mass of 22.9 ml (P = 0.004), abdominal sc fat mass 70.9 ml (P = 0.003), and thigh fat mass 21.3 ml (P = 0.013), whereas thigh muscle mass increased 6.0 ml (P = 0.005). By dual-energy x-ray absorptiometry, lean body mass improved 2.25 kg (P = 0.005), and total fat mass decreased 4.20 kg (P < 0.001). No major side effects were seen. Unrelated to the GH-IGF-I levels at baseline, our results showed that long-term treatment with GH effectively improved body composition and represents a safe, potential treatment option, relieving some of the negative consequences of PWS.