Sleep Behaviors in Infants At High and Low Risk for Developing Autism Spectrum Disorders

Background:  Sleep in children with Autism Spectrum Disorder (ASD) is seen as a serious problem by many parents. Evidence shows prolonged sleep latency (time taken to go to sleep) as well as diminished sleep quality in children with ASD (Mallow, 2006).  Given that about 20% of infants with an older sibling with ASD will develop ASD themselves (Ozonoff et al., 2011), it is important to characterize the sleep behavior of infants high risk for ASD (HR), so that difficulties can be addressed as early as possible.

Previous research using sleep items from a temperament questionnaire (IBQ-R Rothbart, 2000) has shown that at 6 months of age, sleep behaviors are similar in HR infants and those that are low risk (LR) for developing ASD.  However, the groups begin to differentiate at 12 months, when the prevalence of sleep problems increases in HR children (Souders et al., 2010). In addition, direct measures of sleep behavior using actigraphy have demonstrated that children with ASD had greater occurrences of sleep disturbances compared to typically developing children, with particular problems with sleep latency (Souders, et al. 2009).

Objectives:  The primary goal of the current project is to examine sleep behaviors in 6 and 12 month infants and later in toddlers at 24 months using a specialized sleep measure - The Brief Infant Sleep Questionnaire – (Sadeh, 2004) to investigate whether accepted measures of sleep pathology are more severe in HR infants.

Methods:  Data were collected from parent report measures on 6 and 12-month-old infants who were enrolled in a multi-site longitudinal study of brain and cognitive development. The Brief Infant Sleep Questionnaire (BISQ) was administered at one site as part of a battery of cognitive and behavioral measures. Thus far data has been collected from 14 HR infants (mean age: 8.7, 10 males) at high-risk for developing autism and 5 TD infants (mean age: 11.4, 4 males), but data collection is ongoing. Data analyses focused on the 3 areas: sleep latency, duration of sleep and number of night wakings, which were highlighted by Sadeh (2004).

Results:  Preliminary analyses revealed that sleep latency differed between the high risk and low risk groups, with the HR infants taking a 21 minutes to go to sleep and the LR infants taking 11 minutes, t (15) = 2.99, p<.01. However, no differences were found between groups in the number of night wakings or the total duration of sleep. These data suggest that HR infants struggle with going to sleep, confirming results from other studies using direct measures of sleep.

Conclusions:  Sleep difficulties have often been reported in older children and adults with ASD. The current preliminary data suggest that these difficulties may already be present in infancy. Further analyses are planned to investigate the developmental trajectory of sleep behaviors in these infants from 6 to 24 months as data continues to be collected in both infants and in an additional group of toddlers.