Age-related differences in the prevalence and correlates of anxiety in youth with autism spectrum disorders
Introduction
Anxiety symptoms and disorders frequently co-occur in children with autism spectrum disorder (ASD) (e.g., de Bruin et al., 2007, Simonoff et al., 2008, Sukhodolsky et al., 2008). The presence of comorbid anxiety can aggravate core symptoms of ASD (Sukhodolsky et al., 2008), impair daily living skills (Drahota, Wood, Sze, & van Dyke, 2011), and negatively impact relationships with peers, teachers, and family (Kim, Szatmari, Bryson, Streiner, & Wilson, 2000). With autism prevalence estimates rising to epidemic proportions (United States Centers for Disease Control and Prevention, 2007), research on anxiety in ASD is of paramount importance.
A review of existing studies indicates that the prevalence of anxiety symptoms or disorders in children and adolescents with ASD varies widely and ranges from 11% to 84% (White, Oswald, Ollendick, & Scahill, 2009) with a meta-analysis of data showing that about 40% of children and adolescents have at least one anxiety disorder (van Steensel, Bogels, & Perrin, 2011). Most of these studies examine the prevalence of different types of anxiety disorders including generalized anxiety disorder, separation anxiety disorder, specific phobia, social phobia, and obsessive–compulsive disorder. Some studies report a higher prevalence of clinical anxiety in children with ASD compared to the prevalence of clinical anxiety in typically developing (TD) children (Russell & Sofronoff, 2005) and children with other clinical conditions such as conduct disorder (Green, Gilchrist, Burton, & Cox, 2000), language impairment (Gillott, Furniss, & Walter, 2001), Down syndrome (Evans, Canavera, Kleinpeter, Maccubbin, & Taga, 2005), and Williams syndrome (Rodgers, Riby, Janes, Connolly, & McConachie, 2012b). The wide-ranging prevalence of anxiety in children with ASD is likely due to method variance with respect to assessment instrument (interview versus self-report scale), informant (parent versus child), type of anxiety measured (e.g., social anxiety: Bellini, 2006; social, generalized and separation anxiety: Kim et al., 2000; obsessive–compulsive disorder: Reaven & Hepburn, 2003; all anxiety disorders: Leyfer et al., 2006, Simonoff et al., 2008), and anxiety classification (symptoms versus disorders). Furthermore, most of the studies were conducted in small samples (<100 subjects) and few studies report on anxiety in preschool (Gadow et al., 2004, Hayashida et al., 2010, Weisbrot et al., 2005) or lower functioning (Bradley et al., 2011, Bradley et al., 2004) children with ASD.
Few studies have examined rates of subclinical anxiety symptoms in children with ASD. Niditch, Varela, Kamps, and Hill (2012) reported that about 20% of toddler/preschool children (<6 years) and 9% of early elementary school children (6–9 years) with ASD had subclinical levels of anxiety. Strang et al. (2012) found that 21% of children with ASD exhibited subclinical anxiety, but this was across a broad age group of children (6–18 years). Subclinical or subthreshold symptoms reflect a potentially evolving anxiety disorder or a previous anxiety disorder that has partially remitted. Thus, data on both clinical and subclinical anxiety provide a more comprehensive picture of the course of anxiety in children with ASD. Identifying subclinical anxiety is also critical for prevention and treatment. For instance, Ginsburg (2009) found that high risk TD youth, as defined by those with a parental history of anxiety disorder, who received cognitive-behavioral therapy (CBT) had a significantly lower risk of developing anxiety disorders after one year compared to children assigned to a wait list control condition.
Most of the anxiety studies in the ASD population are cross-sectional, report on prevalence in a distinct age group (e.g., adolescents: Bellini, 2004, Bradley et al., 2004, Kim et al., 2000) or calculate a single prevalence across a wide age range of children (e.g., Leyfer et al., 2006: 5–17 years; Muris, Steerneman, Merckelbach, Holdrinet, & Meesters, 1998: 2–18 years). These data set the stage for future research on developmental differences in anxiety since interactions between children and their environment can result in distinct patterns of disease (i.e., with respect to prevalence, phenotype, and risk factors) across different age groups (Rutter, 1988). These patterns can be seen in TD children who exhibit developmental risk periods for anxiety disorders. For example, separation anxiety disorder and specific phobias frequently emerge before adolescence (Becker et al., 2007, Kessler et al., 2005, Wittchen et al., 2000) whereas social phobia typically occurs in late childhood and adolescence (Beesdo et al., 2007, Kessler et al., 2005, Wittchen and Fehm, 2003).
The degree to which age influences the level of anxiety in children with ASD remains unknown. Davis et al. (2011) showed that anxiety increased from toddlerhood to childhood, decreased through young adulthood, and then recurred from young adulthood to older age. Multiple hypotheses were posited to explain these trends including the lack of inhibitory control in toddlers and the use of both adaptive and maladaptive strategies to regulate anxiety in childhood. Strang et al. (2012) conducted a case-control study examining the effect of age (6–11 and 12–18 years) and IQ on emotional symptoms in youth with high functioning autism (HFA). Results showed that levels of anxiety were unaffected by age, IQ, ASD severity, or their interaction. Finally, Niditch et al. (2012) reported that levels of clinical anxiety remained the same from preschool to the early elementary school years among children with ASD. In light of these mixed findings, further research on the relationship between age and anxiety is warranted.
Beyond age, the two other correlates of anxiety in ASD that have been most frequently examined are IQ and ASD severity, neither of which shows any consistent findings. There has been considerable enthusiasm for the hypothesis that children with ASD and higher cognitive functioning may be at greater risk for anxiety because they are more aware of their differences. Empirical support for this hypothesis however has been mixed with some data supporting this relationship (e.g., Estes et al., 2007, Mazurek and Kanne, 2010, Sukhodolsky et al., 2008) but other data showing no effect (Simonoff et al., 2008, Strang et al., 2012). One study found that the relationship between IQ and anxiety in preschool and early elementary school children with ASD is mediated by the level of aggression or social understanding (Niditch et al., 2012). In terms of ASD symptoms, some data report an inverse relationship between anxiety and a global measure of ASD severity (Mazurek & Kanne, 2010) whereas other data show that anxiety is positively correlated specifically with high levels of repetitive behavior (Rodgers et al., 2012a, Spiker et al., 2012, Sukhodolsky et al., 2008). One study found no correlation between the presence of early autistic symptoms and later emotional disorders (Kim et al., 2000).
Few studies have examined whether anxiety co-occurs with other psychiatric symptoms in children with ASD. For example, in TD children, extensive research shows that anxiety disorders are highly comorbid with depression and that depression sequentially follows anxiety in its onset (e.g., Brady and Kendall, 1992, Orvaschel et al., 1995, Seligman and Ollendick, 1998). Investigating comorbidity patterns in children with ASD has implications for delineating psychiatric subtypes that can inform research on pathophysiology and treatment (Gadow, Guttmann-Steinmetz, Rieffe, & deVincent, 2011). Preliminary evidence suggests that anxiety may be comorbid with externalizing disorders among children with ASD (de Bruin et al., 2007, Evans et al., 2005, Kim et al., 2000, Sukhodolsky et al., 2008); however, more research is needed on this topic.
In summary, the literature shows that anxiety research in the pediatric ASD population has increased during the past decade, and that the levels of anxiety may be higher in children with ASD compared to other clinical groups. However, few if any of these studies have incorporated a developmental framework to examine similarities and differences in anxiety characteristics across development. This approach is critical given the dynamic shifts in cognitive, socio-emotional, and neurobiological development that occur from birth to adulthood (Beesdo, Knappe, & Pine, 2009). Hence, the goal of this study is to use a cross-sectional design to explore the prevalence and correlates of anxiety in three age specific groups of children: preschool (under 6 years), school age (6–11 years), and adolescents (12–17 years). Three types of anxiety are examined: separation anxiety, generalized anxiety, and specific phobia, each of which has little overlap with core ASD symptoms. Findings from this study can inform initial hypotheses about age-related differences in anxiety that can be tested using a longitudinal study design. The study goals are exploratory and are as follows:
- 1.
To compare the mean level of clinical anxiety in each age group with the prevalence of anxiety in the general population.
- 2.
To compare anxiety (mean level, percentage of children with clinical anxiety, percentage of children with subclinical anxiety) across the three age groups.
- 3.
To examine the relationship between anxiety and IQ as well as ASD severity within each age group.
- 4.
To explore whether distinct psychiatric comorbidities are associated with anxiety in each age group.
Section snippets
Participants and procedures
This is a cross sectional study of 1316 children and adolescents who were recruited through the Autism Treatment Network (ATN), a multi-site consortium funded by Autism Speaks. The ATN is a clinical and research program comprised of 14 outpatient autism centers in the United States and Canada (see Table 1 for recruitment data). Study data were collected from 2008 to 2010.The Institutional Review Board at each site approved the study.
Subjects included children, ages 2 years 0 months–17 years 6
Comparing demographic and clinical characteristics among the age groups
Table 2 compares demographic and clinical characteristics (except for anxiety, see Section 3.2) across the age groups. Overall age group differences were found for ASD severity (social affect, repetitive behavior, and total score), IQ, and two psychopathology scales (all p < .001); no differences were present for demographic characteristics.
In terms of specific between group differences, school age children had a significantly higher mean IQ than preschool children (β = 7.18, 95% CI [4.03, 10.33], d
Discussion
This study examined the prevalence and correlates of anxiety in children with ASD using a developmental framework. Findings showed that the mean level of anxiety in preschool, school age, and adolescent youth was much higher than in the general population. Additionally, the percentage of children with clinical anxiety in each age group was markedly higher than the prevalence of anxiety in TD youth (preschool: 19% in our sample versus up to 9.5% in TD children; school age and adolescents: 26%
Acknowledgements
The authors acknowledge the members of the Autism Speaks Autism Treatment Network (AS ATN) for use of the data. The data for the study was collected as part of the AS ATN. Further support came from a cooperative agreement (UA3 MC 11054) from 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.
References (99)
- et al.
Epidemiology of specific phobia subtypes: Findings from the Dresden Mental Health Study
European Psychiatry
(2007) - et al.
Anxiety and anxiety disorders in children and adolescents: Developmental issues and implications for DSM-V
Psychiatric Clinics of North America
(2009) - et al.
At risk for anxiety: I. Psychopathology in the offspring of anxious parents
Journal of the American Academy of Child and Adolescent Psychiatry
(1997) - et al.
Co-occurring anxiety and disruptive behavior disorders: The roles of anxious symptoms, reactive aggression, and shared risk processes
Clinical Psychology Review
(2009) - et al.
The developmental epidemiology of anxiety disorders: Phenomenology, prevalence and comorbidity
Child and Adolescent Psychiatric Clinics of North America
(2005) - et al.
Anxiety symptoms across the lifespan in people diagnosed with Autistic Disorder
Research in Autism Spectrum Disorders
(2011) Validity of the CBCL/YSR DSM-IV scales anxiety problems and affective problems
Journal of Anxiety Disorders
(2008)The teen brain: Insights from neuroimaging
Journal of Adolescent Health
(2008)- et al.
Identifying empirically supported treatments for phobic avoidance in individuals with intellectual disabilities
Behavior Therapy
(2008) - et al.
Assessing anxiety with the Child Behavior Checklist and the Teacher Report Form
Journal of Anxiety Disorders
(2007)
Anxiety in children and adolescents with autism spectrum disorders
Research in Autism Spectrum Disorders
Preliminary evidence suggesting caution in the use of psychiatric self-report measures with adolescents with high-functioning autism spectrum disorders
Research in Autism Spectrum Disorders
Comorbid anxiety symptoms in children with pervasive developmental disorders
Journal of Anxiety Disorders
Continuity of psychopathology in a community sample of adolescents
Journal of the American Academy of Child and Adolescent Psychiatry
An initial psychometric evaluation of the CBCL 6-18 in a sample of youth with autism spectrum disorders
Research in Autism Spectrum Disorders
Assessing child and adolescent anxiety in psychiatric samples with the Child Behavior Checklist
Journal of Anxiety Disorders
Behavioral features of Williams Beuren syndrome compared to Fragile X syndrome and subjects with intellectual disability without defined etiology
Research in Developmental Disabilities
Psychiatric disorders in children with autism spectrum disorders: Prevalence, comorbidity, and associated factors in a population-derived sample
The American Academy of Child and Adolescent Psychiatry
Depression and anxiety symptoms in children and ddolescents with autism spectrum disorders without intellectual disability
Research in Autism Spectrum Disorders
Anxiety after sever pediatric closed head injury
Journal of the American Academy of Child and Adolescent Psychiatry
Anxiety in children and adolescents with autism spectrum disorders
Clinical Psychology Review
Life course outcomes of young people with anxiety disorders in adolescence
Journal of the American Academy of Child and Adolescent Psychiatry
Manual for the ASEBA preschool forms and profiles
Manual for the ASEBA school-age forms & profiles
Transition to middle and high school: Increasing the success of students with Asperger Syndrome
Intervention in School & Clinic
Diagnostic and statistical manual of mental disorders, text revision (DSM-IVTR)
Incidence of social anxiety disorder and the consistent risk for secondary depression in the first three decades of life
Archives of General Psychiatry
Social skills deficits and anxiety in high-functioning adolescents with autism spectrum disorders
Focus on Autism and Other Developmental Disabilities
The development of social anxiety in adolescents with autism spectrum disorders
Focus on Autism and Other Developmental Disabilities
Do anxiety and depression have a common pathophysiological mechanism?
Acta Psychiatrica Scandinavica
Comparing rates of psychiatric and behavior disorders in adolescents and young adults with severe intellectual disability with and without autism
Journal of Autism and Developmental Disorders
Psychiatric conditions and behavioural problems in adolescents with intellectual disabilities: Correlates with autism
Canadian Journal of Psychiatry
Comorbidity of anxiety and depression in children and adolescents
Psychological Bulletin
Involvement or isolation? The social networks of children with autism in regular classrooms
Journal of Autism and Developmental Disorders
Statistical Power Analysis for the Behavioral Sciences
Maternal recurrent mood disorders and high-functioning autism
Journal of Autism and Developmental Disorders
Autism severity is associated with child and maternal MAOA genotypes
Clinical Genetics
Brief report: Data on the Stanford–Binet intelligence scales (5th ed.) in children with autism spectrum disorder
Journal of Autism and Developmental Disorders
Clinical assessment of DSM-IV anxiety disorders in fragile X syndrome: Prevalence and characterization
Journal of Neurodevelopmental Disorders
High rates of psychiatric co-morbidity in PDD-NOS
Journal of Autism and Developmental Disorders
Developmental course of psychopathology in youths with and without intellectual disabilities
Journal of Child Clinical Psychology and Psychiatry
Autism and familial major mood disorder: Are they related?
Journal of Neuropsychiatry and Clinical Neurosciences
Effects of cognitive behavioral therapy on daily living skills in children with high functioning autism and concurrent anxiety disorders
Journal of Autism and Developmental Disorders
Concurrent validity of the child behavior checklist DSM-oriented scales: Correspondence with DSM diagnoses and comparison to syndrome scales
Journal of Psychopathology and Behavioral Assessment
Level of intellectual functioning predicts patterns of associated symptoms in school-age children with autism spectrum disorder
American Journal on Mental Retardation
The fears, phobias, and anxieties of children with autism spectrum disorders and Down Syndrome: Comparisons with developmentally and chronologically age matched children
Child Psychiatry and Human Development
Assessment of childhood anxiety using structured interviews: Patterns of agreement among informants and association with maternal anxiety
Psychological Assessment
Psychiatric symptoms in preschool children with PDD and clinic and comparison samples
Journal of Autism and Developmental Disorders
Depression symptoms in boys with autism spectrum disorder and comparison samples
Journal of Autism and Developmental Disorder
Cited by (74)
IQ, parent- and self-reports of child anxiety and salivary cortisol in a sample of children with autism spectrum disorder
2023, Research in Developmental DisabilitiesLongitudinal follow-up of subsequent psychiatric comorbidities among children and adolescents with autism spectrum disorder
2023, Journal of Affective DisordersExperiences with licensing by autistic drivers: An exploratory study
2022, Procedia Computer ScienceEffects of the video game ‘Mindlight’ on anxiety of children with an autism spectrum disorder: A randomized controlled trial
2020, Journal of Behavior Therapy and Experimental PsychiatryFamily accommodation of anxiety in a community sample of children on the autism spectrum
2020, Journal of Anxiety DisordersCitation Excerpt :Anxiety is recognised as one of the most common co-occurring diagnoses, with meta-analyses suggesting that approximately 40 % of children on the spectrum will receive a clinical anxiety diagnosis (van Steensel, Bogels, & Perrin, 2011). There is also an increasing recognition that many children on the autism spectrum experience “subclinical anxiety” (Vasa et al., 2013), which may still impact upon their daily life. Recent work demonstrated that both parents and teachers report elevated anxiety symptomatology in children on the autism spectrum as young as 5 years old (Adams, Simpson, & Keen, 2018; Keen, Adams, Simpson, den Houting, & Roberts, 2019, (Simpson, Adams, Wheeley, & Keen, 2019).
Developmental cascades between insistence on sameness behaviour and anxiety symptoms in autism spectrum disorder
2023, European Child and Adolescent Psychiatry