Six-month sleep-wake organization and stability in preschool-age children with autism, developmental delay, and typical development

Abstract

This study examined sleep-wake patterns in 3 matched comparison groups of preschool-aged children: children with autism (AUT), children with developmental delay (DD) without AUT, and children who are developing typically (TYP). Sleep was assessed via actigraphy and parent-report diaries for 7 consecutive 24-hr periods across 3 time points: at enrollment (n = 194), 3 months later (n = 179), and 6 months after enrollment (n = 173). At each recording period, children in the AUT group slept less per 24-hr period, on average, and were less likely to awaken at night than children in the other two groups. In contrast, children in the DD group had more frequent and longer duration nighttime awakenings than children in the AUT group. Overall, children in the 2 neurodevelopmentally disordered groups demonstrated more night-to-night variability in their sleep-wake measures than children in the TYP group.

FIGURE 1

Estimated trajectories of sleep behaviors and between-child and within-child variability by diagnosis for bedtime and 24-hr sleep at enrollment (Time 1), 3 months later (Time 2), and 6 months after enrollment (Time 3). Note. Figure portrays the estimated average paths for bedtime and 24-hr sleep over 6 months. The horizontal lines depict the estimated mean trajectories over time for each group. The error bars in Figure 1a and 1c represent the variability around the mean of each diagnostic group (between-child standard deviations). The error bars in Figure 1b and 1d represent the night-to-night variability for each diagnostic group (within-child standard deviations). Children in the typically developing (TYP) group had a trend to gradually go to bed later over time (p < .10), and this change was significantly different from both of the neurodevelopmentally disordered groups (both ps < .05). All children had a slight decline in their average 24-hr sleep over time (p < .05). As expected, within-child variability, determined by the size of the error bars in Figure 1b and 1d, was greater than between-child variability, as depicted in Figure 1a and 1c, for all three diagnostic groups. AUT = autism; DD = developmental delay without AUT.