Obstructive sleep apnea is position dependent in young infants.

Background: Obstructive sleep apnea in infants with Pierre Robin sequence is sleep-position dependent. The influence of sleep position on obstructive events is not established in other infants.

Methods: We re-evaluated ten-year pediatric sleep center data in infants aged less than six months, with polysomnography performed in different sleep positions. We excluded infants with syndromes, genetic defects, or structural anomalies.

Results: Comparison of breathing between supine and side sleeping positions was performed for 72 infants at the median corrected age of 4 weeks (interquartile range (IQR) 2-8 weeks). Of the infants, 74% were male, 35% were born prematurely, and 35% underwent study because of a life-threatening event or for being a SIDS sibling. Upper airway obstruction was more frequent (obstructive apnea-hypopnea index (OAHI), p < 0.001), 95th-percentile end-tidal carbon dioxide levels were higher (p = 0.004), and the work of breathing was heavier (p = 0.002) in the supine than in the side position. Median OAHI in the supine position was 8 h (IQR 4-20 h), and in the side position was 4 h (IQR 0-10 h).

Conclusions: Obstructive upper airway events in young infants are more frequent when supine than when sleeping on the side.

Impact: The effect of sleep position on obstructive sleep apnea is not well established in infants other than in those with Pierre Robin sequence. A tendency for upper airway obstruction is position dependent in most infants aged less than 6 months. Upper airway obstruction is more common, end-tidal carbon dioxide 95th-percentile values higher, and breathing more laborious in the supine than in the side-sleeping position. Upper airway obstruction and obstructive events have high REM sleep predominance. As part of obstructive sleep apnea treatment in young infants, side-sleeping positioning may prove useful.