Associations Between Repetitive Behaviors and Anxiety Symptoms In Children with Autism Spectrum Disorders

Background:  Anxiety symptoms and repetitive/restricted behaviors are commonly reported in individuals with autism spectrum disorders (ASD). Generalized anxiety, panic attacks, phobias and obsessions/compulsions have all been reported. While repetitive behaviors have been well investigated, the other anxiety symptoms have received limited attention. Additionally, little is known about the relationships between the severity and type of repetitive behaviors and anxiety symptoms in children with ASD.

Objectives : The purpose of this investigation is to examine anxiety symptoms in a well-characterized sample of children with ASD and to determine if there are associations between repetitive/stereotyped behaviors and specific anxiety symptom domains.

Methods :  Participants included children with ASD between the age of 3 and 12 years.  ASD diagnosis was based on the Autism Diagnostic Observation Schedule (ADOS), Autism Diagnostic Interview Revised (ADI-R) and expert clinical opinion. Parents completed the Repetitive Behavior Scale-Revised (RBS-R) and behavioral measures assessing anxiety symptoms including the Spence Children's Preschool Anxiety Scale (SCPAS) or Spence Children's Anxiety Scale (SCAS), and the Early Childhood Inventory- 4 (ECI-4) for ages 3 to 5 or Child Symptom Inventory-4 (CSI-4) for ages 6 to 12. Spearman’s rho correlations were performed to examine associations between specific anxiety symptoms and repetitive behaviors.

Results : To date, behavioral data and anxiety symptom measures have been collected on 48 children with ASD (mean age: 7.7 ± 2.4). All of the RBS-R subscales were significantly associated with at least one anxiety domain. Stereotyped Behavior was positively associated with Specific Phobia (r=.334; p=.008), Injury Fears (r=.251; p=.049) Separation Anxiety (r=.310; p=.014), Generalized Anxiety (GAD) (r=.523; p=<.001), Social Phobia (r=.330; p=.008) and Compulsions (r=.408; p=.001). Self-Injurious Behavior was correlated with GAD (r= .405; p= .001), Obsessions (r=.301; p=.017), and OCD (r=.269; p=.034). Compulsive Behavior, as measured by the RBS-R, was associated with dimensional scoring of the CSI-4/ECI-4 on GAD (r=.289; p=.022) and Compulsions (r=.431; p=<.001). Additionally, Ritualistic Behavior was associated with several domains including Injury Fears (r=.261; p=.040), Generalized Anxiety on both the SCAS/SCPAS (r=.284; p=.025) and on the CSI-4/ECI-4 (r=.388; p= .002). Interestingly, Restricted Behaviors were only associated with GAD (r=.313; p=.013) and Compulsions (r=.388; p=.002). Finally, Sameness Behaviors was associated with several symptoms including higher Panic (r=.477; p=.001); Injury Fears (r=.275; p=.031) and GAD on the SCAS/SCPAS (r=.408; p= .001) and on CSI-4/ECI-4 (r=.555; p=<.001), Social Phobia (r=.333; p=.008) and Specific Phobia (r=.338; p=.007). In contrast, the Separation Anxiety domain on the SCAS/SCPAS was not significantly associated with any of the RBS-R subscales.

Conclusions: These preliminary data suggest that many anxiety symptom domains are correlated with repetitive behaviors in children with ASD supporting the hypothesis of a common pathogenic mechanism for these clinical features. Overall, severe stereotyped, sameness, and restricted behaviors may be better predictors of higher anxiety symptoms.  Further studies with larger sample sizes and a wider age range are warranted to determine the correlates of repetitive behaviors and co-occurring anxiety symptoms which may allow for more targeted diagnostic tools and treatments for individuals with these debilitating symptoms.