ESPE Abstracts

Context: Most children with Prader-Willi syndrome (PWS) develop scoliosis. Scoliosis has a prevalence of 80% in children with PWS older than 10 years, who were not treated with growth hormone (GH). GH is an approved treatment for children with PWS and improves psychomotor development and body composition. The onset and progression of scoliosis are generally associated with an accelerated growth velocity and GH treatment might cause accelerated growth. Since GH treatment has also been shown to increase lean body mass, it might counteract the effect of the accelerated growth on scoliosis development. A previous study supported this hypothesis, as no difference was found in onset of scoliosis and curve progression between GH-treated children with PWS and controls. However, this study had only a follow-up period of two years. There are, to our knowledge, no studies about the long-term effect of growth hormone on the onset and progression of scoliosis in children with PWS.

Objective: To investigate the effects of 8 years GH treatment on the onset and progression of scoliosis and to assess whether there are correlations between serum IGF-1 levels, lean body mass, the onset of puberty and the development of scoliosis.

Design: Prospective cohort study during 8 years of GH.

Setting: Dutch PWS Reference Center.

Intervention: All children were treated with GH 1 mg/m²/day (≈0.035 mg/kg/day).

Methods: Every year standardized x-rays of the spine are performed in children with PWS. The Cobb angles were measured by two independent experts.

Main outcome measures: Onset of scoliosis, determined as a Cobb angle of 10º or higher, and progression of the scoliotic curve, expressed as the change in the Cobb angle during 8 years of GH.

Results: 90 children with PWS were treated with GH for 8 years. The statistical analysis are in progress. We will have the results of this study early July 2019, so we can present them during the ESPE 2019 meeting in Vienna. We hypothesize that, in children with PWS, 8 years of GH treatment has no negative effects on the onset and progression of scoliosis in children with PWS.