Effects of growth hormone treatment after final height in Prader-Willi Syndrome

Background: GH improves height velocity, and body composition in PWS children. Preliminary data also suggest improvement of psychosocial functioning during GH. When epiphysial fusion is complete and final height is reached, GH-treatment has to be discontinued. However, discontinuation of GH results in a decrease of lean body mass, an increase of body fat percentage and a deterioration of psychosocial behaviour. A preliminary study showed that also young adults with PWS might benefit from GH-treatment, with regard to body composition, and psychosocial wellbeing.
Objectives:
Primary objectives
To assess effects of GH-treatment versus placebo on
- body composition
- carbohydrate metabolism
- psychosocial functioning
- sleep-related breathing disorders
- circulating lipids
- blood pressure
Secondary objectives
- To study the effects of GH-treatment versus placebo on thyroid hormone levels, IGF-I and IGF binding proteins, adiponectin, ghrelin.
- To study compliance to the diet.
Patients: subjects with PWS, aged 18-24 years, who reached final height after they were treated with GH according to the Dutch National GH study in children with PWS (ISRCTN49726762), or after they were otherwise treated with GH (at least 2 years) during childhood.
Intervention: Treatment with GH: Genotropin 0.67 mg/m2/day s.c. or placebo
Design/Assessments: After stratification for BMI, gender, originally followed in the GH study vs. otherwise GH-treated patients, subjects will be randomized to either placebo or GH-treatment group, according to a double blind, placebo-controlled cross-over design during the first 2 years. After 2 years, all patients receive GH treatment in a dose of 0.67 mg/m2/day, after ATT-GHRH test has been performed. Anthropometric assessments and blood pressure will be performed every 3 months. Six-monthly, assessment of body composition (DXA), carbohydrate metabolism and circulating lipids and other laboratory parameters will be performed. Yearly, evaluation of sleep-related breathing (polysomnography), and cognition and behaviour (GIT, TVZ) will be performed.

GH treatment after reaching final height is beneficial for body composition and social wellbeing in young adults with PWS

Treatment with GH: Genotropin 0.67 mg/m2/day s.c. or placebo