Objective: To characterize polysomnographic sleep architecture in children with Down syndrome and compare findings in those with and without obstructive sleep apnea.
Study design: Case series with retrospective review.
Setting: Single tertiary pediatric hospital (2005-2018).
Methods: We reviewed the electronic health records of patients undergoing polysomnography who were referred from a specialized center for children with Down syndrome (age, ≥12 months). Continuous positive airway pressure titration, oxygen titration, and split-night studies were excluded.
Results: A total of 397 children were included (52.4% male, 81.6% Caucasian). Mean age at the time of polysomnography was 4.7 years (range, 1.4-14.7); 79.4% had obstructive sleep apnea. Sleep variables were reported as mean (SD) values: sleep efficiency, 85% (11%); sleep latency, 29.8 minutes (35.6); total sleep time, 426 minutes (74.6); rapid eye movement (REM) latency, 126.8 minutes (66.3); time spent in REM sleep, 22% (7%); arousal index, 13.3 (5); and time spent supine, 44% (28%). There were no significant differences between those with obstructive sleep apnea and those without. Sleep efficiency <80% was seen in 32.5%; 34.3% had a sleep latency >30 minutes; 15.9% had total sleep time <360 minutes; and 75.6% had an arousal index >10/h. Overall, 69.2% had ≥2 metrics of poor sleep architecture. REM sleep time <20% was seen in 35.3%. REM sleep time decreased with age.
Conclusion: In children with Down syndrome, 32.5% had sleep efficiency <80%; 75.6% had an elevated arousal index; and 15.9% had total sleep time <360 minutes. More than a third of the patients had ≥3 markers of poor sleep architecture. There was no difference in children with or without obstructive sleep apnea.
Keywords: Down syndrome; obstructive sleep apnea; pediatrics; sleep architecture.