Endocrine Abstracts

JOINT2950

Introduction: Prader Willi Syndrome (PWS) has a broad clinical spectrum whereas respiratory disorders are major causes of morbidity and mortality across the lifespan. The approach must include close monitoring to minimize the risks.

Aim: To describe respiratory and sleep patterns in a cohort of PWS children.

Materials and Methods: Retrospective evaluation of respiratory and sleep patterns in a cohort of 25 pediatric PWS patients admitted at Ricardo Gutierrez Children hospital from 2002 to 2024. Variables analyzed were body mass index (BMI kg/m²), pituitary function (TSH, free T4, cortisol), recombinant human growth hormone treatment (rhGH 1 mg/m²/d), tonsils volume; obstructive sleep apneas (OSA), central apneas (CSA), nocturnal hypoventilation by Polysomnography (PSG) and daytime sleepiness by multiple sleep latency test (MSLT).

Results: Median age at admission was 3.3yr (0.4 to 13.6yr), 52% boys. The genetic mechanism was the deletion of 15q11.2-q13 chromosomal region (60%) and maternal uniparental disomy (40%). Hypothyroidism was diagnosed in 21% and none had adrenal insufficiency until their last examination. Basal median BMI was 2.35 SDS (-1.9 to 11 SDS). Median time between diagnosis and respiratory evaluation was 4.9yr (0.8 to 18.9yr). Anamnesis revealed snoring in 56% and clinical examination showed tonsillar hypertrophy in 83% of the cases. Twenty-one patients were evaluated prior to rhGH indication: 18/21 (86%) had OSA, 3 CSA and 1 nocturnal hypoventilation. Ulterior indications were only clinical follow up in 8/21, tonsillectomy in 5/21, tonsillectomy and non-invasive mechanical ventilation in 1. Seven patients were suitable to begin rhGH treatment whereas 4 patients required specific interventions before rhGH indication. Three patients were already under rhGH at first respiratory evaluation: 1 had mild OSA. None of the patients who underwent tonsillectomy developed velopharyngeal insufficiency post-surgery. Sleep disorders were diagnosed in 5/25: narcolepsy in 3 cases and cataplexy in 2. Individualized medical interventions were implemented. Six patients under rhGH developed respiratory disorders during follow-up (1 to 4 yr): 5 tonsillar hypertrophy and OSA, and 1 CSA concomitant with respiratory infection. Median ΔBMI was 0.01 (-0.37 to 2.86 SDS). In patients under rhGH there was no significant correlation between the occurrence of respiratory events and ΔBMI.

Conclusion: Respiratory and sleep disorders were a prevalent comorbidity in this cohort of PWS children and detected only by careful anamnesis and specific tests performed by trained specialists. Regular examination of respiratory and sleep disorders before and during rhGH treatment should be included in the multidisciplinary approach of PWS.