Original ArticleSleep problems in children with autism spectrum disorder: examining the contributions of sensory over-responsivity and anxiety
Introduction
Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder that is characterized by difficulties with social communication and interaction and by restricted and repetitive behaviors and activities [1]. In addition to these primary symptoms, individuals with ASD also experience high rates of medical and behavioral comorbidities [2], [3]. Among these, sleep problems are particularly common for children with ASD, with prevalence rates ranging from 50% to 80% [4], [5], [6], [7]. Most studies have found that difficulties falling asleep and night waking are the most common types of sleep problems in children with ASD, with additional evidence of disturbances in circadian rhythm [6], [8]. For many children and families with ASD, sleep problems can contribute to significant distress and impairment over and above the effects of primary ASD symptoms. Sleep problems can have detrimental effects on learning and cognition [9], and they have been associated with an increased severity of stereotypic and challenging behaviors [10], [11], [12] and decreased quality of life [13] among children with ASD. Children's difficulties with sleep also affect the entire family, and they often result in increased parental stress and decreased well-being [14].
The etiology of sleep problems in children with ASD is thought to be multifactorial, including potential disruption in circadian rhythms and melatonin regulation and difficulties with sleep hygiene [6], [15], [16]. The majority of research and clinical practice guidelines for addressing sleep problems in children with ASD have focused on these factors. However, some researchers and clinicians have suggested that hyperarousal [17], [18], [19] and sensory reactivity [8] may also play a role in the etiology of sleep problems in children with ASD. Although there is evidence to support this from the typically developing (TD) population [20], [21], [22], similar research has not yet been conducted among children with ASD.
In TD individuals, insomnia has been found to be associated with hyperarousal, cortical excitability, and hypothalamic–pituitary–adrenal (HPA)-axis involvement (as evidenced by increased cortisol secretion) [20], [21]. It is possible that hyperarousal may also underlie sleep difficulties for children with ASD, particularly given their increased risk for arousal-related difficulties. In fact, compared to other clinical and nonclinical groups, children with ASD are at high risk for both anxiety [23], [24] and sensory over-responsivity [25], [26]. Importantly, these separate sets of symptoms are also characterized by hyperarousal. However, research has only recently begun to examine the possibility that these difficulties may relate to sleep problems in children with ASD [27], [28].
There is strong evidence of comorbidity of anxiety and sleep problems in the general population, with a markedly high prevalence of insomnia among individuals with anxiety disorders (70–90%) [29]. In addition, studies of both adolescents and adults have found that anxiety is a longitudinal predictor of insomnia, predating the onset of insomnia in the great majority of cases, while depression appears to occur subsequent to insomnia [30], [31]. These results provide evidence of a specific directional association from anxiety to insomnia in the general population.
There is a growing body of evidence that anxiety is also associated with sleep problems in individuals with ASD. For example, anxiety-related nighttime behaviors were common in a sample of 69 children with autism and sleep disturbance [32], parent-rated sleep disturbance was correlated with anxiety in children with autism [11], and sleep-related fears were found to be more common among children with Asperger's syndrome than among TD children [33]. Anxiety was also associated with insomnia in studies of adults with Asperger's disorder [34], [35]. More recently, a study of children with intellectual disability and/or ASD found that sleep problems were significantly correlated with anxiety across the entire sample. However, separate results for the ASD group were not reported [36]. A recent analysis of the Autism Speaks Autism Treatment Network (AS ATN) registry database also found that children with ASD who had sleep problems had higher internalizing symptoms than those without sleep problems. However, although anxiety comprises an aspect of the larger internalizing symptom domain, the specific relationship between anxiety and sleep problems was not reported [37]. Richdale and Baglin found that sleep problems were associated with both parent- and self-reported symptoms of anxiety in a sample of 17 children with high-functioning ASD [18]. More recently, Richdale and colleagues found that adolescents with high-functioning ASD experienced more presleep arousal than TD adolescents, and that self-reported anxiety and presleep arousal were both correlated with sleep problems in the ASD group [28].
Sensory over-responsivity represents another symptom area that has theoretical relevance to both anxiety and sleep problems. Sensory over-responsivity is common among children with ASD, with estimates ranging from 56% to 70% [38], [39], and it is characterized by negative responses (eg, distress, avoidance, or hypervigilance) to specific sensory stimuli, such as light, sound, and/or tactile experiences [40], [41]. There is increasing evidence that sensory over-responsivity and anxiety represent closely related yet conceptually distinct phenomenon [42]. Previous studies have found significant relationships between these variables in TD children [43], [44], as well as children with ASD [45], [46], [47]. Similarly, there is some evidence that both conditions are characterized by increased HPA axis involvement [48]. This is not surprising given that the HPA axis regulates responses to stressful stimuli, and it is well connected to the amygdala, which is also activated by aversive stimuli from various sensory modalities [49].
Given that sensory over-responsivity, like anxiety, has been associated with hyperarousal, these particular symptoms may also be associated with sleep difficulties. In fact, there have been a few studies suggesting a link between sleep problems and sensory over-responsivity. Among TD children, sensory problems have been found to be associated with sleep problems [22]. Children with autism have also been found to have greater sensitivity to the sleep environment than children with other developmental problems [50]. More recently, a small study of 27 children with ASD found that sensory problems, particularly sensory avoiding, were correlated with sleep problems in children with ASD. Furthermore, physiological markers of stress, including salivary cortisol and galvanic skin response following the presentation of sensory stimuli, were highly related to sleep problems [27]. These preliminary findings indicate a need for further research on the relationships among sensory over-reactivity, anxiety, and sleep problems in children with ASD.
Evidence from previous studies provides a strong basis for predicting that sensory over-responsivity and anxiety may be highly related to the development and maintenance of sleep problems in children with ASD. The current study examined the possible interrelatedness of this group of symptoms among a large well-characterized sample of children and adolescents with ASD. The following hypotheses were tested:
- 1)
Sensory over-responsivity will be associated with increased anxiety in children with ASD.
- 2)
Anxiety will be associated with increased sleep problems in children with ASD.
- 3)
Sensory over-responsivity will be associated with increased sleep problems in children with ASD.
- 4)
Sensory over-responsivity and anxiety will each be associated with sleep problems in children with ASD when included jointly within a multivariate model.
Section snippets
Participants
Participants in the current study included 1347 children and adolescents enrolled in the AS ATN who had complete data on the measures required for the analyses. The AS ATN is a multisite network of autism treatment and research centers located throughout the United States and Canada. The AS ATN supports a large clinical registry database, which includes a standard battery of medical and behavioral measures collected at enrollment and across time. The current study examined cross-sectional data
Results
Table 1 provides sample characteristics of the younger (2–5 years) and older (6–18 years) groups.
Discussion
Medical problems frequently accompany the core symptoms of ASD and they can have a significant detrimental impact on health and quality of life [76], [77], yet the relationships among these problems are not well understood. Thus, the purpose of this study was to examine the relationships among three common co-occurring problems for children with ASD: sleep problems, sensory problems, and anxiety. Despite evidence suggesting that these three conditions may be highly related, this was the first
Conflict of interest
The ICMJE Uniform Disclosure Form for Potential Conflicts of Interest associated with this article can be viewed by clicking on the following link: http://dx.doi.org/10.1016/j.sleep.2014.11.006.
Acknowledgements
This research activity was supported by a cooperative agreement UA3 MC11054 through the U.S. Department of Health and Human Services, Health Resources and Services Administration, Maternal and Child Health Research Program to the Massachusetts General Hospital. This work was conducted through the Autism Speaks Autism Treatment Network serving as the Autism Intervention Research Network on Physical Health.
References (90)
Medical comorbidities in autism: challenges to diagnosis and treatment
Neurother
(2010)- et al.
Commonly studied comorbid psychopathologies among persons with autism spectrum disorder
Res Dev Disabil
(2014) - et al.
Parental perception of sleep problems in children of normal intelligence with pervasive developmental disorders: prevalence, severity, and pattern
J Am Acad Child Adolesc Psychiatry
(2005) - et al.
Sleep problems in autism spectrum disorders: prevalence, nature, possible biopsychosocial aetiologies
Sleep Med Rev
(2009) - et al.
Sleep disturbances and autism
Sleep Med Clin
(2008) - et al.
Sleep problems as possible predictors of intensified symptoms of autism
Res Dev Disabil
(2004) - et al.
Variables related to sleep problems in children with autism
Res Autism Spect Disord
(2009) - et al.
The relationship between Health-Related Quality of Life and sleep problems in children with Autism Spectrum Disorders
Res Autism Spect Disord
(2014) - et al.
Sleep correlates of pervasive developmental disorders: a review of the literature
Res Dev Disabil
(2011) - et al.
The hyperarousal model of insomnia: a review of the concept and its evidence
Sleep Med Rev
(2010)
Hyperarousal and insomnia: state of the science
Sleep Med Rev
Anxiety in children and adolescents with autism spectrum disorders
Clin Psychol Rev
Anxiety in children and adolescents with autism spectrum disorders
Res Autism Spect Disord
The role of insomnia, pre-sleep arousal, and psychopathology symptoms in daytime impairment in adolescents with high-functioning autism spectrum disorder
Sleep Med
The association of insomnia with anxiety disorders and depression: exploration of the direction of risk
J Psychiatr Res
Sleep, anxiety and challenging behaviour in children with intellectual disability and/or autism spectrum disorder
Res Dev Disabil
The human amygdala and the emotional evaluation of sensory stimuli
Brain Res Rev
One-year course and predictors of abdominal pain in children with autism spectrum disorders: the role of anxiety and sensory over-responsivity
Res Autism Spect Disord
An initial psychometric evaluation of the CBCL 6–18 in a sample of youth with autism spectrum disorders
Res Autism Spect Disord
Sleep patterns in children with and without autism spectrum disorders: developmental comparisons
Res Dev Disabil
Parasomnias and movement disorders in children and adolescents
Child Adolesc Psychiatr Clin N Am
Interactions between evening and nocturnal cortisol secretion and sleep parameters in patients with severe chronic primary insomnia
Neurosci Lett
Nocturnal cortisol and melatonin secretion in primary insomnia
Psychiatry Res
A cognitive model of insomnia
Behav Res Ther
Preliminary evidence suggesting caution in the use of psychiatric self-report measures with adolescents with high-functioning autism spectrum disorders
Res Autism Spect Disord
Diagnostic and statistical manual of mental disorders, fifth edition (DSM-5)
Sleep problems in children with autism spectrum disorders, developmental delays, and typical development: a population-based study
J Sleep Res
Sleep behaviors and sleep quality in children with autism spectrum disorders
Sleep
The role of sleep in learning and memory
Science
Sleep is associated with problem behaviors in children and adolescents with Autism Spectrum Disorders
Res Autism Spect Disord
Children with autism: sleep problems and mothers’ stress
Focus Autism Other Dev Disabl
An investigation into sleep characteristics of children with autism and Asperger's Disorder
J Paediatr Child Health
Sleep in children with autism spectrum disorders
Curr Treat Options Neurol
Self-report and caregiver-report of sleep and psychopathology in children with high-functioning autism spectrum disorder: a pilot study
Dev Neurorehabil
Sleep problems in autism: prevalence, cause, and intervention
Dev Med Child Neurol
Sensory hypersensitivity as a contributing factor in the relation between sleep and behavioral disorders in normal schoolchildren
Behav Sleep Med
A comparison of the performance of children with and without autism on the Sensory Profile
Am J Occup Ther
Comparison of sensory profile scores of young children with and without autism spectrum disorders
Am J Occup Ther
Sensory processing, physiological stress, and sleep behaviors in children with and without autism spectrum disorders
OTJR
Anxiety and sleep problems: emerging concepts and theoretical treatment implications
Curr Psychiatry Rep
The role of anxiety and depression in the development of insomnia: cross-sectional and prospective analyses
Psychol Health
Sleep patterns and sleep disorders in children with autistic spectrum disorders: insights using parent report and actigraphy
Dev Med Child Neurol
Sleep in children with Asperger syndrome
J Autism Dev Disord
Insomnia is a frequent finding in adults with Asperger syndrome
BMC Psychiatry
Sleep in young adults with Asperger syndrome
Neuropsychobiology
Cited by (186)
Sleep Problems in Autism Spectrum Disorder
2024, Pediatric Clinics of North AmericaQuality of life and clinical correlates in cognitively-able autistic adults: A special focus on sensory characteristics and perceived parental support
2024, Journal of the Formosan Medical AssociationExploring bidirectional relationships: Child sleep duration, child behavior problems, and parenting stress in families of children with autism spectrum disorder
2023, Research in Autism Spectrum Disorders