P0051 PP SLEEP-BREATHING DISORDERS IN OBESE CHILDREN

Abstract

Introduction: Nocturnal respiratory dysfunction associated to obesity was mainly evaluated in adults. The aim of our study was to determine frequency of sleep-breathing disorders in obese children and to precise their mechanisms. Methods: Sleep studies were performed in 54 children (22 boys, aged 12.0 ± 2.6 years) with severe obesity (BMI z-score 4.9±1.2 SD) and included mean SaO2 during sleep, maximal variation of PCO2 between awakening and sleep, respiratory events index (REI defined as episodes of apnea/hypopnea per hour), snoring and arousal indexes. Univariate and multivariate analyses were assessed between sleep studies variables and phenotypic characteristics (neck circumference, HOMA, fasting leptin and lipids measurements) and airway resistances (RWA). Results: 22% of children had a mean SaO2 during sleep above 95%, and 48% an increase in PCO2 superior to 10 mmHg between awakening and sleep. A severity criteria (REI > 10 or snoring index > 300 or arousal index > 10) was found in 41% of cases. REI and snoring index were significantly correlated to BMI z -score (p=0.03 and p=0.01), neck circumference (p=0.002 and p=0.004) and RWA (p=0.05 and p=0.01). A positive correlation between HOMA and arousal index was found (p=0.006). Using multivariate analyses with HOMA and BMI z-score as independent variables, HOMA still correlated with arousal index (p=0.001). Conclusion: 1) Sleep-breathing disorders are frequent in obese children; 2) Airway resistance due to increased cervical fat depots, obesity severity and insulin resistance are the main mechanisms for severe sleep-breathing disorders in obese children.