Prevalence of Sleep-Disordered Breathing in Prader-Willi Syndrome.

Introduction: Sleep-disordered breathing (SDB) is common in patients with Prader-Willi Syndrome (PWS). However, the prevalence of SDB varies widely between studies. Early identification of SDB and factors contributing to its incidence is essential, particularly when considering growth hormone (GH) therapy. Objectives: The aims of the study were to describe the prevalence and phenotypes of sleep-disordered breathing (SDB) in patients with Prader-Willi syndrome (PWS) and to determine the effects of age, gender, symptoms, GH therapy and body mass index on SDB severity. Methods: This study was a retrospective chart review of all patients with genetically confirmed Prader-Willi syndrome who underwent diagnostic overnight polysomnography (PSG) in the sleep laboratory at Sidra Medicine. Clinical and PSG data of enrolled patients were collected. Results: We identified 20 patients (nine males, eleven females) with PWS who had overnight sleep polysomnography (PSG) at a median age (IQR) of 5.83 (2.7-12) years. The median apnea-hypopnea index (AHI) was 8.55 (IQR 5.8-16.9) events/hour. The median REM-AHI was 27.8 (IQR 15-50.6) events/hour. The median obstructive apnea-hypopnea index (OAHI) was 7.29 (IQR 1.8-13.5) events/hour. The median central apnea-hypopnea index (CAHI) was 1.77 (IQR 0.6-4.1) events/hour. Nineteen patients (95%) demonstrated SDB by polysomnography (PSG) based on AHI ≥1.5 events/hour. Nine patients (45%) were diagnosed with obstructive sleep apnea (OSA). Three patients (15%) were diagnosed with central sleep apnea (CSA). Seven patients (35%) were diagnosed with mixed sleep apnea. No correlations were observed between AHI and age, gender, BMI, symptoms, or GH therapy. However, REM-AHI was significantly correlated with BMI (P=0.031). Conclusion: This study shows a high prevalence of SDB among our patients with PWS. Obstructive sleep apnea was the predominant phenotype. BMI was the only predictor for high REM-AHI. Further studies of large cohorts are warranted to define SDB in PWS and design the appropriate treatment.

Pediatric outpatient non-invasive ventilation program: Reflections on the first experience from the Middle East.

Long-term noninvasive ventilation (NIV) is being progressively used in children. The current guidelines recommend NIV initiation in the hospital during overnight polysomnography (PSG) titration study. Due to the logistic, socioeconomic, and financial difficulties including bed availability, an outpatient program for NIV initiation and patients/parents counseling to prevent delay and provide cost-effective care has been commissioned. Hence, this study reports on the clinical outcome of our program as it represents the first reported experience from the middle east. A retrospective review of electronic medical charts was conducted for all patients with PSG-confirmed sleep-related breathing disorders (SRBD) who were evaluated and treated in the NIV clinic in the pediatric pulmonary clinic at Sidra Medicine from January 2020 to November 2021. Patients' data included demographics, PSG results, and NIV clinic records. The results show that twenty-eight patients (17 male, 11 female) were included during the study period. The patients' median age at NIV initiation was 11 ± 5.17 years. The median BMI was 32.72 ± 15.91 kg/m2. The most common diagnosis was morbid obesity in 9 (32%) of the patients. The identified SRBD based on the diagnostic PSG were obstructive sleep apnea in 21 patients, hypoventilation in 3 patients, mixed apnea in 3 patients, and central apnea in 1 patient. The median total Apnea-Hypopnea Index (AHI) was 12.7 (0.7-153.9) events per hour. The main reason for the initial NIV clinic visit was NIV initiation in 19 patients. Upon follow-up, six patients were successfully weaned off NIV support by the treating pulmonologist. Five patients refused to use NIV at home. Fifteen out of the remaining seventeen patients used NIV ≥  4 hours per night (subjective adherence: 88%). Twelve patients used the NIV for ≥  24 nights per month (70.6%). All parents reported that the clinic experience was beneficial and helped them to be more comfortable with applying the NIV machine at home. In conclusion, pediatric NIV outpatient programs are achievable and beneficial, especially in developing countries. Pediatric NIV clinics managed by a specialized and experienced team play important role in the initiation and follow-up of NIV support. They provide alternative pathways for the care of pediatric patients, education, and support of their families, and decrease the load on intensive care and sleep laboratory units. Studies about cost-effectiveness are needed to evaluate the impact of implementing outpatient NIV programs on sleep laboratories and hospital admission rates.