Visual gain control abnormalities in Autism Spectrum Disorders

Abstract

Limited population-based data on prevalence of childhood vision impairment (VI) and hearing loss (HL), and their co-occurrence with autism spectrum disorder (ASD) exists.To examine prevalence and characteristics of VI, HL and co-occurring ASD among 8-year-olds in metropolitan Atlanta 2000–2008.We used data from the population-based Metropolitan Atlanta Developmental Disabilities Surveillance Program. Prevalence, birth and parental characteristics, presence and severity of other co-occurring developmental disabilities, and age of earliest identification of ASD, were examined for children with VI and HL, by co-occurring ASD.VI and HL prevalences were 1.2 and 1.3 per 1000 8-year-olds, respectively. Approximately 6–7% of children with VI or HL had co-occurring ASD. Children with VI or HL with co-occurring ASD differed from those without co-occurring ASD by select birth characteristics and the presence of other co-occurring DDs. The median age of earliest known ASD diagnosis was significantly later among children with VI and ASD compared to children with ASD without VI (79 vs. 56 months). Children with HL and ASD were first evaluated by a community provider significantly earlier than those with ASD without HL (40 vs. 50 months).The frequency of co-occurring ASD with VI and HL is higher than the population prevalence of ASD. The significant delays in diagnosis of ASD in children with VI and lack of earlier diagnosis of ASD among children with HL despite earlier evaluation highlight the importance of developing screening tools for early identification of ASD among children with VI and HL.