ESPE Abstracts

Background: Knowledge about the effect of GH treatment on adaptive functioning in children with Prader–Willi syndrome (PWS) is limited.

Objective and hypotheses: The aim of this study was to investigate the effect of GH treatment on adaptive functioning in children with PWS.

Method: Vineland Adaptive Behavior Scale (VABS) was assessed at start, at the end of the RCT, and after 7 years of GH treatment. In the RCT, 75 children (42 infants and 33 prepubertal children) with PWS were included. Subsequently, 53 children were treated with long-term GH 1 mg/m² per day.

Results: Children with PWS were delayed in their adaptive skills in all domains. Older age and lower intelligence were associated with more delay in adaptive functioning compared to references. On short-term, no effect of GH treatment was found between the GH-treated and untreated group in the RCT, in both infants and prepubertal children. However, after 7 years of GH treatment, there was significantly less delay in adaptive functioning in infants of the former GH treatment group vs the former untreated group in all domains (communication: P<0.001, daily living skills: P<0.001, socialization: P<0.001, motor skills: P<0.001). An earlier age at start of GH treatment during infancy (0–3.5 years) was associated with less developmental delay in communication (P<0.05), daily living skills (P<0.05), socialization (P<0.05) and motor skills (P<0.005), but in children who started GH treatment above the age of 3.5 years, this association was not found.

Conclusion: Our study demonstrates a marked delay in adaptive functioning in infants and children with PWS. The earlier GH treatment was started during infancy, the better the adaptive skills on the long-term.