Association of Motor Stereotypies with Emotional Dysregulation and Anxiety/Depression Symptoms in Children with Autism Spectrum Disorder

Background: Comorbidities such as anxiety and challenging behaviours are common in children with autism spectrum disorder (ASD). These comorbidities are often linked to emotional dysregulation (ED) and are frequently accompanied by motor stereotypies (MS). Objective: This study aimed primarily to examine the association between lifetime motor stereotypies (LMS) and both emotional dysregulation (ED) and anxiety/depression symptoms (ADS) in children with ASD. Additionally, a secondary objective was to explore the association between ED and the lifetime broader spectrum of restricted and repetitive behaviours (RRBs), and their specific subtypes. Methods: The study included 151 children with ASD (ages 3–11). ADS and ED were assessed using the Child Behaviour Checklist (CBCL) and the Child Behaviour Dysregulation Profile (CBCL-DP), respectively, while LMS and lifetime RRBs were evaluated via the Autism Diagnostic Interview-Revised (ADI-R). Data were analyzed using regression models. Results: Frequent LMS were significantly associated with ED and ADS. Gender, intellectual disability (ID), and ASD severity did not significantly influence these relationships. Age had a significant effect on the association between frequent LMS and ADS. No significant correspondence was found between ED and lifetime RRBs in general or with subtypes of RRBs. Conclusions: Our findings suggest that frequent LMS are associated with ED and ADS in children with ASD. Identifying ASD subgroups based on the presence of LMS may contribute to the development of detection methods and targeted and effective interventions for ED. Differences observed between LMS and other RRBs in relation to ED support the notion that low- and high-level repetitive behaviours involve distinct clinical features and should be studied independently.