Beyond diagnosis: Are there predictor variables of ADHD in adults with ASD and moderate to severe intellectual disability levels?

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) is a common comorbidity in individuals with autism spectrum disorder (ASD), yet the manifestation and diagnosis of ADHD in adults with ASD and severe intellectual disability (ID) remain under-researched. This research aims to identify transdiagnostic variables that may indicate the presence of ADHD in a population in which additional diagnoses can be complicated due to communication constraints.

METHODS AND PROCEDURES: The study involved 83 adults with dual diagnoses of ASD and ID, and a test battery was used to assess different variables: Conners' Adult ADHD Rating Scales-Observer Report: Screening Version; Adult Executive Functioning Inventory; Emotion Regulation Checklist. According to the score considered in the Conners' scale (>70), 26.5 % of the sample met the criteria for suspecting an ADHD diagnosis.

OUTCOMES AND RESULTS: The findings suggest that higher levels of executive dysfunction and emotional dysregulation are predictive of a clinically relevant level of ADHD symptoms in adults with ASD and severe ID. The research contributes to a deeper understanding of ADHD in a population with complex diagnostic challenges, providing valuable insights for more accurate diagnoses and targeted interventions.

CONCLUSIONS AND IMPLICATIONS: The study highlights the importance of considering executive and emotional functioning when assessing for ADHD in adults with ASD and ID and suggests that these variables may serve as key indicators for identifying and intervening in comorbid ADHD in this population.