Three years of growth hormone treatment in young adults with Prader-Willi Syndrome previously treated with growth hormone in childhood: Effects on glucose homeostasis and metabolic syndrome.

Abstract

Growth hormone (GH) has been approved for children with Prader-Willi syndrome (PWS) and significantly improves body composition in adults with PWS. Adults with PWS are predisposed to develop impaired glucose tolerance (IGT) and diabetes mellitus type 2 (DMT2). Continuation of GH maintains body composition, but GH is known to induce insulin resistance, which might affect glucose homeostasis. Studies on long-term effects of GH treatment in adults are very limited. To investigate effects of 3years of GH treatment on glucose homeostasis and prevalence of metabolic syndrome (MS) in adults with PWS. Open-label, prospective study. 43 young adults with PWS. Dutch PWS Reference Center. Glucose and insulin during oral glucose tolerance test. Estimated mean (95% CI) fasting glucose and insulin levels remained stable during 3years of GH treatment. Glucose being 4.6 (4.4-4.8) mmol/l at start and 4.7 (4.6-4.9) mmol/l after 3years (P=.07); insulin being 59.5 (45.2-75.8) pmol/l and 56.7 (45.2-69.6) pmol/l resp. (P=.72). Sex, ethnicity and fat mass percentage were significantly associated with fasting glucose levels, while IGF-I or GH-dose were not. Blood pressure, lipids and prevalence of MS remained stable during 3years of GH. IGT prevalence was variable over time, six patients had IGT at start and eleven after 3years of GH. One patient developed DMT2. However, prevalence of IGT or DMT2 was not significantly higher after 3years than at study start. Threeyears of GH treatment in adults with PWS does not impair glucose homeostasis and does not lead to an increased prevalence of DMT2.