Effect of Growth Hormone Replacement Therapy on Metabolic Characteristic in Young Adults with Prader-Willi syndrome
Introduction: Prader-Willi syndrome (PWS) is a complex, multisystemic genetic disorder caused by the lack of expression of paternally inherited genes in the PWS critical region on chromosome 15. Growth hormone (GH) deficiency is a common endocrine problem in PWS patients not only in childhood but also in adults. Recombinant human growth hormone (rhGH) therapy serves not only to achieve an ultimate height within a desired range, but also to compensate for metabolic abnormalities, lower body mass and reduce fat mass percentage (%FM). The aim of the study was to assess the metabolic profile of adults with PWS and compare a GH treated cohort (childhood onset of treatment) with an untreated cohort. Material and Methods: This is a retrospective, non-randomised study including 25 young adults diagnosed with PWS. Patients were divided into 2 groups depending on GH replacement therapy (1st group never treated and 2nd treated since childhood within the framework of the Therapeutic Health Programme in Poland). The treatment was monitored with respect to IGF-1 serum levels. In all patients BMI, FM%, carbohydrate metabolism and thyroid function were assessed and statistically analyzed to compare outcomes both groups. Results: The group of GH treated patients, which comprised 19 individuals, had a statistically lower FM%, BMI, as well as a normal IGF-1 level in contrast to the untreated cohort. Insulin level was within normal ranges across all groups, yet lower levels were attested in the GH-treated individuals. HOMA-IR index was statistically lower in the GH-treated group. No significant differences between analysed groups were observed in regard to thyroid function. Conclusions: While metabolic disturbances are common in a young-adult with PWS, GH replacement therapy is safe and effective in achieving not only proper growth in children, but also normal metabolic profile in adults. It plays a crucial role in reducing the individual metabolic risk and should be an important part of PWS treatment programs.