Beth A. Malow, MD, MS
Professor of Neurology and Pediatrics, Burry Chair in Cognitive Childhood Development, Vanderbilt University, Nashville, TN
Vanderbilt Kennedy Center for Human Development, Nashville TN
Sleep is an essential component of a healthy life, like food and oxygen. When we don’t sleep well, we feel irritable and have difficulty concentrating. With this in mind, imagine how a child on the autism spectrum feels and behaves without sleep (and how their sleep-deprived caregivers feel)!
Given how common sleep problems are, and how profoundly they affect children and their families, it is timely to consider what we already know and what the future holds in our understanding of sleep in autism spectrum disorders (ASD).
What we’ve learned so far: Sleep problems are common in children with ASD, have many causes, and affect child and family functioning.
Sleep problems are common in children with autism spectrum disorders (ASD) — ranging from 50-80% (Couturier et al., 2005; Krakowiak et al., 2008; Souders et al., 2009; Goldman et al. 2011), with similar rates across all ages and cognitive levels. Insomnia, defined as difficulty falling asleep or staying asleep, is the most common sleep problem. Causes (Reynolds and Malow, 2011) range from medical conditions (e.g., gastrointestinal disorders, seizures, sleep apnea, attention deficit disorder, anxiety) and the medications used to treat these conditions (e.g., stimulants, antidepressants) to behavioral factors unique to the child with autism (for example, sensory sensitivities, difficulty transitioning to bedtime activities). Children, regardless of language abilities, may not understand parents expectations about sleep. Parents, in turn, may be too overwhelmed by other priorities and stressors to put a sleep plan in place. Proper identification of the causes of sleep difficulties in children with ASD is critical to successful treatment.
Behavioral and pharmacological treatments that improve sleep positively affect daytime functioning in the child and family (as reviewed in Malow et al., 2012) and may minimize the need for medications that target behavioral symptoms. For example, in 80 children receiving sleep education delivered by their parents (Malow et al., 2013), improvements in anxiety, attention, repetitive behavior, pediatric quality of life, and parenting sense of competence were also observed. While improving sleep does not necessarily change the core features of ASD, addressing sleep concerns may ameliorate co-occurring medical conditions such as epilepsy or anxiety. A well-rested child may also be more engaged in therapies that improve social interactions, and his well-rested parents may be empowered to advocate more effectively for his needs.
What we need to learn: What therapies for sleep are effective? Can we predict which treatments will work for subgroups of children?
We still have much more to learn about which therapies are effective for sleep in children with ASD. In particular, we need to understand the impact of treating co-occurring medical and psychiatric conditions (e.g., gastrointestinal disorders, anxiety) on sleep-onset and sleep-maintenance insomnia. For example, insomnia, anxiety, and GI disturbances may coexist in the same child, but whether one causes or contributes to the other coexisting conditions is unresolved. An alternative possibility is that insomnia, anxiety, and GI disturbance share an underlying mechanism. One possible mechanism may be autonomic dysfunction (Kushki, 2013), with sympathetic hyperarousal and parasympathetic underarousal.
While behavioral treatments for sleep have shown promise in ASD and other neurodevelopmental disorders (Malow et al., 2013; Weiskop et al., 2005 and others reviewed in Vriend, 2011), determining subgroups of children who are most responsive to these therapies are needed. For example, children with short sleep duration and frequent night wakings (in whom medical causes of sleep disturbance have been excluded), or those with limited verbal skills, may have a differing treatment response to behavioral interventions than children with sleep onset delay. This differing response may result from biological causes, or alternatively, a poorer response to the intervention. In those requiring medications, we need to determine which medicines are safe and effective for a variety of sleep problems (sleep onset delay, night wakings). Supplemental melatonin has been studied to a greater extent than any other medication for sleep in ASD, but large well-controlled studies have been limited (Rossignol, 2011). Genetic factors, including those related to melatonin synthesis, may also be important (Melke, 2008) in determining which child may respond to a specific therapy.
Another subgroup of individuals with ASDs worthy of study are adolescents and young adults. My colleagues at Vanderbilt are studying sleep patterns this population at baseline (Dr. Suzanne Goldman, funding from Autism Speaks), and with behavioral treatment (Dr. Whitney Loring, funding from Organization for Autism Research).
The area of sleep and autism is ripe for continued research, in terms of causes, treatments, and overlap with many other areas, ranging from medical co-occurring conditions to genetic and other biological markers to treatment trials. Being vigilant (pun intended) to the role of sleep in autism research has high potential to advance our knowledge of autism subtypes as well as our toolbox for real world treatments that impact people with ASD and their families.
Couturier JL, Speechley KN, Steele M, Norman R, Stringer B, Nicolson R. (2005) Parental perception of sleep problems in children of normal intelligence with pervasive developmental disorders: prevalence, severity, and pattern. J Am Acad Child Adolesc Psychiatry 44: 815-822.
Goldman SE, Surdyka K, Cuevas R, Adkins K, Wang L, Malow BA. (2009) Defining the sleep phenotype in children with autism. Dev Neuropsychol. 34(5), 560-73.
Kushki A, Drumm E, Pla Mobarak M, Tanel N, Dupuis A, Chau T, Anagnostou E. Investigating the autonomic nervous system response to anxiety in children with autism spectrum disorders. PLoS One. 2013;8(4):e59730. doi: 10.1371/journal.pone.0059730. Epub 2013 Apr 5.
Krakowiak P, Goodlin-Jones B, Hertz-Picciotto I, Croen LA, Hansen RL. (2008) Sleep problems in children with autism spectrum disorders, developmental delays, and typical development: a population-based study. J Sleep Res. 17(2):197-206.
Malow BA, Byars K, Johnson K, Weiss S, Bernal P, Goldman SE, Panzer R, Coury D, Glaze DG. A practice pathway for the identification, evaluation and management of insomnia in children and adolescents with autism spectrum disorders. Pediatrics. 2012;130 Suppl 2:S106-24.
Malow BA, Adkins KW, Reynolds A, Weiss SK, Loh A, Fawkes D, Katz T, Goldman SE, Madduri N, Hundley R, Clemons T. Parent-Based Sleep Education for Children with Autism Spectrum Disorders. J Autism Dev Disord. 2013 Jun 11.
Melke J, Goubran Botros H, Chaste P, Betancur C, Nygren G, Anckarsater H, Rastam M, Stahlberg O, Gillberg IC, Delorme R, Chabane N, Mouren-Simeoni MC, Fauchereau F, Durand C M, Chevalier F, Drouot X, Collet C, Launay JM, Leboyer M, Gillberg C, Bourgeron T. Abnormal melatonin synthesis in autism spectrum disorders. Mol Psychiatry 2008; 13(1):90-98
Reynolds AM, Malow BA. Sleep in Children with Autism Spectrum Disorders. In: Owens J, Mindell JA, Eds. Pediatric Clinics of North America 2011; 58(3):685-98.
Rossignol D, Frye R. Melatonin in autism spectrum disorders: a systemic review and meta-analysis. Developmental Medicine & Child Neurology 2011; 53(9), 783-792.
Souders MC, Mason TB, Valladares O, et al. Sleep behaviors and sleep quality in children with autism spectrum disorders. SLEEP 2009;32:1566-1578.
Vriend, J. L., Corkum, P. V., Moon, E. C., & Smith, I. M. (2011). Behavioral interventions for sleep problems in children with autism spectrum disorders: Current findings and future directions. Journal of Pediatric Psychology, 36(9), 1017–1029.
Weiskop S, Richdale A, Matthews J. Behavioural treatment to reduce sleep problems in children with autism or fragile X syndrome. Dev Med Child Neurol. 2005;47(2):94-104.