Frequency and Characteristics of Sleep Apnea Syndrome in Pediatric Patients with Duchenne Muscular Dystrophy

<bold>Introduction:</bold> Pulmonary function tests and polysomnography (PSG) serve as an important tool in the management of neuromuscular disorders. Our aim is to define characteristics of sleep apnea syndrome (SAS) in DMD patients who had PSG data. Method: This retrospective study includes 54 DMD patients (≤ 18 years) referred to sleep laboratory between January 2016-July 2023. <bold>Results:</bold> The average age and body mass index at the time of PSG was 11.1±3.8 years;19±4kg/m2. Of the patients, 25.9%(n=14) were non-ambulatory; 40.7% (n=22) had scoliosis. Mean values for forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC); FEV1 and FVC zscores were 84.7±26.4%pred; 73.7±22.6%pred;-1.9±2.7; -3.7±2.8. Mean ejection fraction (EF) was 62.1±9.5. Hypoventilation was documented in 9.2% (n=5); SAS was classified as moderate/severe in 27.7% (n=15), and mild in 37% (n=20). Fifteen patients (27.7%) within the study cohort required noninvasive mechanic ventilation. A weak positive correlation was found between age at the time of PSG and the severity of AHI (p= 0.015; r:0.33). Diseases’ stage was positively correlated with age and AHI severity (p<0.001, r:0.7; p= 0.027, r: 0.41); negatively correlated with FEV1 zscore, FVC zscore, EF (p<0.001, r:-0.7; p<0.001, r:-0.65; p= 0.02, r:-0.3). EF was significantly lower in patients with moderate/severe SAS compared to patients with mild SAS (p=0.017, p=0.04). FVC below 80% was associated with the risk of SAS (OR: 15.6, p=0.003). <bold>Conclusion:</bold> This study is yet another example highlighting the value of pulmonary function tests and PSG studies as a core component of standards of care in proactive management of DMD patients.