Sleep characteristics in children with Down syndrome.

Abstract

Obstructive sleep apnea syndrome is common in children with Down syndrome (DS). Little is known about sleep patterns, especially arousals, awakenings, and movements during sleep in children with DS. To determine the characteristics of sleep disorders in children with DS and to define the associations between respiratory disturbance and arousals, awakenings, and movements. The study included 23 children with DS, compared with 13 children with primary snoring. All underwent a 6- to 8-hour sleep study. The respiratory disturbance index was significantly higher in the children with DS (2.8 +/- 2.3 events/h vs 0.6 +/- 0.4 events/h; P <.05). Sleep was significantly fragmented in children with DS, who had a significantly higher arousal/awakening (A/Aw) index (24.6 +/- 7.9 events/h) compared with the comparison group (17.6 +/- 4.0 events/h) (P <.02). A higher percentage of jerks associated with A/Aw and respiratory event-associated A/Aw was observed in patients with DS (45.2% +/- 25% and 8.6% +/- 6.4%, respectively) compared with the control patients (10.2% +/- 4.5% and 1.5% +/- 2.1%) (P <.02). The median length of occurrences of stage 2 sleep was 27% shorter in the DS group (P <.03). The number of shifts from "deeper" to "lighter" stages of non-rapid eye movement sleep was 30% greater (P <.02) in the DS group. Children with DS have significant sleep fragmentation, manifested by frequent awakenings and arousals, which are only partially related to obstructive sleep apnea syndrome.