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

Objective: Childhood sleep disordered breathing (SDB) peaks in the preschool years. We aimed to compare the effects of SDB on polysomnographic characteristics between preschool and school aged children.

Methods: One hundred and fifty-two preschool (3-5 y) and 105 school-aged (7-12 y) children, referred for assessment of SDB, 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 SDB 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 SDB 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 SDB severity.

Conclusions: We have demonstrated clinically important, age-related differences in sleep architecture in children with SDB. Preschool children with SDB maintain sleep efficiency and awaken fewer times throughout the night than do school aged children with a comparable severity of SDB, but experience more central apneas. This may have implications for the outcomes and treatment of SDB in children of different ages.