Differential effects of sleep disordered breathing on polysomnographic characteristics in preschool and school aged children

Objective: Childhood sleep disordered breathing (SOB) peaks in the preschool years. We aimed to compare the effects of SOB on polysomnographic characteristics between preschool and school aged children. Participants and Methods: One hundred and fifty-two preschool (3-5 y) and 105 school-aged (7-12 y) children, referred for assessment of SOB, plus controls (39, 3-5 y and 34, 7-12 y) with no history of snoring underwent overnight polysomnography. Subjects were grouped by their obstructive apnea hypopnea index (AHI) into those with primary snoring, mild obstructive sleep apnea (OSA), and moderate/severe OSA. The effects of SOB severity on sleep architecture and respiratory characteristics were compared between the age cohorts using quantile regression. Results: There was an average reduction in median sleep efficiency of 3.5% (p = 0.004) and an average increase in median WASO of 2% (p = 0.08) between the age cohorts across the severity groups, with sleep efficiency falling and WASO increasing with increasing SOB severity in the school-aged, but not the preschool, cohort. There was an average difference in median central AHI of 0.6 events/h (p < 0.001) between the age cohorts across the severity groups, with the 3-5 y old cohort but not the 7-12 y old cohort having more central apneas with increasing SOB severity. Conclusions: We have demonstrated clinically important, age-related differences in sleep architecture in children with SOB. Preschool children with SOB maintain sleep efficiency and awaken fewer times throughout the night than do school aged children with a comparable severity of SOB, but experience more central apneas. This may have implications for the outcomes and treatment of SOB in children of different ages. (C) 2012 Elsevier B.V. All rights reserved.