POLYSOMNOGRAPHY CHARACTERISTICS OF CHILDREN WITH OBESITY: A SINGLE CENTER RETROSPECTIVE STUDY

Abstract Introduction The constellations of symptoms known as obstructive sleep apnea (OSA) results from either partial or complete airway obstruction during sleep. This affects effective gas exchange and disrupts sleep architecture resulting in sleep fragmentation with downstream immediate and long-term adverse effects. Obesity is a significant risk factor in childhood OSA, especially in post-pubertal children. Obese/overweight children have been found to have significantly higher rates of OSA than their normal-weight counterparts, independent of tonsillar size. Polysomnography characteristics (PSG) comparing children with obesity with and without comorbidities (Hypertension, Diabetes or Pre-diabetes) has not been previously described. Methods Retrospective analysis of 190 obese children (BMI>95th centile), age between 7-18 years with AHI ≥5/hour met the criteria for the data analysis. Clinical, demographic and PSG parameters of children with obesity with and without co-morbidities were compared using Wilcoxon rank sum test. Correlation (Spearman non-parametric) and regression model was employed to explore associations between demographic and PSG characteristics. Results Majority of the obese children (mean BMI 33.2) had mild OSA, with no significant difference in AHI between the two groups. Children with obesity and comorbidities were older with higher BMI. There was no difference in BMI between the two groups after adjusting for BMI z scores. AHI increased with increasing BMI centiles. In our regression model, peak ETCO2 was associated with Black race, AHI, rhinitis and inversely associated with asthma. Peak ETCO2 increased with BMI. Oxygen at baseline, nadir and desaturation duration inversely correlated with BMI-centiles. Older children had lower O2 nadir. Black race was associated with higher desaturation, supine AHI, and arousal index. Supine AHI was higher with rhinitis. Average heart rate when awake, NREM and REM increased with higher BMI. Conclusion In our study, majority of the children had mild OSA with no significant difference in AHI between obese children with and without comorbidities. AHI, average heart rate and peak ETCO2 increased with BMI. O2 nadir was lower in older children and with higher BMI. Black race was associated with higher peak ETCO2, higher desaturation and supine AHI. Children with obesity and comorbidities were older with higher BMI suggesting synergistic effect of BMI and duration of obesity. Support (If Any)