ESPE Abstracts

Introduction: Most patients with Prader-Willi syndrome (PWS) have a mild to moderate cognitive impairment. Growth hormone (GH) treatment has positive short- and long-term effects on cognition in children with PWS. Few studies, however, have investigated the effects of GH on cognitive functioning in adults with PWS.

Objective: To investigate the effects of 3 years GH treatment on cognitive functioning in young adults with PWS who were GH-treated during childhood.

Design: Open-label, prospective study.

Setting: Dutch PWS Reference Center

Methods: Patients were treated with 0.33 mg GH/m²/day (~0.012 mg/kg/day). Cognitive functioning was measured by Wechsler Adult Intelligence (WAIS) tests.

Results: 46 young adults with PWS with a median age of 19 (IQR 17 – 21) years were tested. Estimated mean (95% CI) Total, Verbal and Performance IQ remained stable during 3 years of GH treatment. Total IQ being 66 (63-69) at start and 67 (64-71) after 3 years, P=0.30; Verbal IQ being 65 (62-68) and 66 (62-70), resp., P=0.31 and Performance IQ being 67 (63-70) and 67 (63-72) resp., P=0.42. 24% of the young adults at start, and 34% after 3 years, had a Total IQ above 70, the cut-off for mental disability.

Conclusions: Three years of GH treatment with a lower dose in young adults with PWS maintains Total, Verbal and Performance IQ.