IMPE Abstracts

Natural history of Prader-Willi syndrome (PWS) is greatly improved when recombinant growth hormone (rGH) treatment is started early in life, turning out to be effective and safe. However, safety alerts persists in relation to possible ventilatory effects of rGH treatment in the first months. For this reason clinical guidelines recommend close monitoring by specialists in sleep-related disordered breathing and otorhinolaryngologists.

Objective: To describe the growth and monitoring of ventilatory sleep disorders in a cohort of PWS children treated with rGH before 3 years old.

Material and methods: retrospective data on growth and sleep respiratory polygraphy with oxycapnography (SRPO) were analyzed. From a cohort of 21 patients with genetic diagnosis of PWS, 11 patients (64% girls) under 3 years old at the beginning of rGH treatment were included. Height and weight were evaluated at baseline and at 12 and 24 months post-treatment. SRPO was compared at baseline and between 12-24 months under treatment. Outcomes were determined by measuring obstructive sleep apnea (OSA) and peripheral blood oxygen saturation.

Results: Mean age at rGH onset was 1 year (0.58-2.5 years), mean initial height -2.5sds and mean weight/height (W/H) ratio of 98%. At 12 and 24 months the mean height (sds) was -0.56 and -0.47 respectively and mean W/H ratio 115% and 112.8% 8/11 patients had SRPO prior starting rGH. 5 of 8 patients (63%) had a normal study with an index of apneas and hypopneas per hour of sleep (AHI/h) less than 1 and (37%) had mild OSA (AHI index/h greater than 1). During 24 months after treatment parameters remained stable in 7/11 patients. 4 patients progressed to mild and only one patient presented a moderate index (AHI/h greater than 5) His rGH treatment continued under strict follow up.

Conclusions: All patients presented a good growth response achieving near 2 sds in height, with stable weight gain. No significant trends over time for any adverse sleep-related outcomes, specifically severe obstructive or central sleep apnea. Our findings are similar to those found in literature.