Central and Obstructive Apnoea-Hypopnea Indices Pre and Post Growth Hormone Commencement in Children with Prader-Willis Syndrome Following Introduction of a Screening Programme

Introduction: Children with Prader Willi syndrome (PWS) have sleep disordered breathing (SDB) and previous studies have conflicting reports on the impact of growth hormone (GH) on SDB in them, hence this study. Methods: A screening program for children with PWS for sleep apnoea was introduced in 2015 at Southampton Children’s Hospital. This evaluated children using cardiorespiratory sleep studies prior to and at 3, 6, 9, 12 and 24 months post starting GH. The derived data was expressed as median(IQR) and Wilcoxon rank signed test was used to test associations using SPPS version 23. Results: Twenty-five children were commenced on GH since 2015. Of these, 16 have completed the screening programme and results are presented. The median (IQR) age of commencement was 1.4(0.7-4.3) years. The median (IQR) CAHI showed a trend towards decreasing value of CAHI from pre-GH commencement until 12±1 months. On the other hand, there was an early rise in OAHI at 3 months post baseline and then a more gradual rise over 24 months with a significantly higher OAHI at 24±1 months post GH commencement compared to OAHI prior to GH commencement (p=0.04). Four patients had a clinically significantly elevated OAHI (>5). Three of these were commenced on NIV, three had GH discontinued and two had adenotonsillectomy Conclusion: This data demonstrates that starting GH in PWS is associated with an initial CAHI improvement alongside increasing OAHI with GH use. Could this rise in OAHI be more about children reaching the standard age when adenotonsillectomy is indicated? Potentially, ongoing/more studies will help to make stronger conclusions.