The relationship of comorbid anxiety symptom severity and challenging behaviors in infants and toddlers with autism spectrum disorder

• Researchers have found comorbid psychopathologies exacerbate the rate of challenging behaviors in individuals with ASD.
• Differences in challenging behaviors were explored in children with ASD demonstrating varying levels of anxiety impairment.
• Significant differences in the overall rate of challenging behaviors as well as in specific types of behaviors were found between groups.

The rates of comorbid anxiety as well as the presentation of challenging behaviors are elevated within the autism spectrum disorder (ASD) population. The current study utilizes the Baby and Infant Screen for Children with aUtIsm Traits (BISCUIT) to explore the relationship of anxiety/repetitive behavior symptom severity and challenging behaviors in infants and toddlers with ASD. Children with ASD who evinced more severe impairment associated with anxiety/repetitive behavior (n = 94) demonstrated higher rates of overall challenging behaviors than those with ASD who evinced no to minimal anxiety impairment (n = 291). Specifically, a comparison of individual challenging behavior items indicated that the infants and toddlers with moderate to severe anxiety impairment exhibited more significant challenging behaviors under the domains of aggression/destruction, stereotypies, and self-injurious behavior than children with no to minimal impairment. This study adds to the literature evidencing an exacerbation of challenging behaviors by comorbid psychopathology in individuals with ASD. Clinical implications of these results are discussed.