How does ASD symptomology correlate with ADHD presentations?

Elevated rates of attention deficit/hyperactivity disorder (ADHD) symptoms have been documented in the autism spectrum disorder (ASD) population. However, the recent restructuring of the ASD diagnostic category and its respective symptom structure has elicited concern about how these changes may impact prevalence rates, the deliverance of services, and the rates of comorbid psychopathology. At present, few researchers have investigated the prevalence rates of specific ADHD presentations within ASD populations. As we seek to increase our understanding of ADHD symptom manifestation in ASD populations it is important to establish base rates of attention and hyperactive symptoms. The current manuscript sought to investigate the prevalence of inattention and impulsive symptoms in 1722 infants and toddlers. Individuals were separated into three diagnostic groups for analyses, a DSM-5 ASD group, an atypically developing group, and a DSM-IV-TR ASD group. Initial analysis extended previous research by demonstrating significantly elevated rates of inattention/impulsive symptoms in toddlers meeting DSM-5 criteria for ASD when compared to the DSM-IV-TR ASD and atypically developing groups. Additional analysis demonstrated that ASD symptom severity was positively correlated with inattention/impulsive symptoms regardless of primary diagnosis. Lastly, analyses examined the exhibition of inattention and impulsive symptoms separately within diagnostic groups. Results suggest that the expression of impulsive and inattentive symptoms did not significantly differ within diagnostic groups. Published by Elsevier Ltd.