Eczema and related atopic diseases are associated with increased symptom severity in children with autism spectrum disorder.

Growing evidence indicates that autism spectrum disorder (ASD) has diverse genetic, neurological, and environmental factors that contribute to its neurodevelopmental course. Interestingly, childhood ASD is often accompanied by skin disorders, such as eczema, and other related atopic manifestations. This link may be due to the shared embryonic origin of epidermal and neural tissue. Accordingly, we consider the potential influence of a skin-brain co-vulnerability and ensuing atopic cascade on ASD symptomatology by investigating whether atopic disorders (asthma, allergies, eczema and hay fever) are associated with increased symptom severity in children with ASD. Overall, 45 atopic and 93 non-atopic children with ASD were assessed using the ADOS-2 on scores of total, social and non-social symptoms. Differences in ASD symptom severity were further evaluated as a function of atopic disease type. Atopic children displayed greater symptom severity overall and in the social domain, relative to non-atopic participants. Atopic children were 2.4 times more likely to experience overall impairments classified within the ADOS-2 highest-level severity bracket and 2.7 times more likely to show social difficulties in this range. Moreover, those reporting comorbid eczema displayed increased symptom severity relative to both their non-atopic peers and those reporting asthma and allergies. Taken together, findings indicate that atopic disorders, and particularly comorbid eczema, are associated with increases in ASD symptom severity. Findings provide grounds for future investigations into this link between childhood skin diseases and ASD symptom severity to advance our understanding of neurodevelopment and to develop targeted assessment and intervention opportunities.