Typical and Atypical Anxiety in Autism Spectrum Disorder

Abstract

Objective. There is confusion regarding the presentation and correct classification of anxiety symptoms in autism spectrum disorders (ASD) as comorbid anxiety disorders, core ASD symptoms or a separate syndrome. The present study examined the degree to which Diagnostic Statistical Manual-Fourth Edition (DSM-IV) anxiety disorders ("typical anxiety") can be reliably distinguished from atypical presentations in ASD ("atypical anxiety"). To inform their classification, the study also assessed how these typical and atypical presentations were differentially related to child characteristics (i.e. IQ, language ability) and features of anxiety disorders (i.e., anxious self-talk) and ASDs (i.e., ASD symptomology, sensory abnormalities). Method. Youth (N = 59; 7 - 17 years; IQ > 60) diagnosed with ASD and their parents completed a semi-structured diagnostic interview (ADIS-C/P) adapted to measure both typical and atypical presentations of anxiety as well as self- and parent-report measures. Results. Seventeen percent of the sample met criteria for a typical anxiety disorder, 15% for an atypical anxiety disorder and 31% for both typical and atypical disorder variants. Whereas IQ, language ability, anxious self-talk and sensory sensitivity significantly predicted typical anxiety, atypical anxiety was significantly associated with anxious self-talk and ASD symptomology. Conclusions. Results suggest that ASD youth display two, phenomenological distinct classes of anxiety. These typical and atypical presentations likely reflect comorbid anxiety and a novel variant of anxiety, which may be missed by current, unmodified anxiety measures. How these presentations differentially respond to interventions and contribute to the range of results regarding the prevalence and presentation of anxiety in ASD warrants investigation.