Obstructive Sleep Apnea (OSA): Differences Between Normal-Weight, Overweight, Obese and Morbidly Obese Children

The severity of obstructive sleep apnea (OSA) in children determines perioperative management and is an indication for postoperative polysomnography (PSG). There is a paucity of data on differences and predictors of OSA severity in children in different weight categories. The primary objective was to compare demographic, clinical and polysomnography parameters in normal-weight, overweight, obese and morbidly obese children and to identify factors that are associated with OSA severity. Healthy children aged 2-18 who underwent polysomnography at an academic children's hospital were included in the study. Demographics, clinical findings, and polysomnogram parameters were recorded. Children were categorized as normal-weight, overweight, obese, or morbidly obese based on CDC criteria. Differences were assessed with linear and logistical regression models. Significance was set at p<0.05. 290 children were included. Morbidly obese were older than normal-weight children (mean 8.0±0.5 versus 5.8±0.3; p<0.001) but less likely to have a normal PSG (16% versus 48%; p=0.02). There were no differences in gender, ethnicity, birth status (term or pre-term), tonsil size or AHI between the different weight categories. Sleep efficiency and %REM were decreased in morbidly obese children (p<0.05). The AHI was positively correlated with increasing BMI z-score as a function of increasing age (p<0.001). There are important differences in children with OSA in different weight categories. OSA severity is correlated with a combination of increasing age and weight but not with either variable independently. This study suggests that obese and morbidly obese older children are most likely to have severe OSA and should undergo routine PSG.