Co-Morbid Hearing Loss and Autism: Complex Presentation and Diagnosis

Background: Research has shown that autism can exist with co-morbid conditions such as Down Syndrome, Intellectual Disabilities, Seizures, vision loss and hearing loss. Despite higher prevalence rates of autism in children with hearing loss (estimated to be 1 in 81) there exists little research pertaining to diagnostic, intervention, and characteristics of these children. Objectives: To develop a functional understanding of key characteristics of children with co-morbid hearing loss and autism. Methods: A national sample (n = 52) of children with hearing loss and autism was recruited to complete several autism screeners including the Social Responsiveness Scale, Social Communication Questionnaire, and the Gilliam Autism Rating Scales- 2nd edition. Of those children, in-depth one-on-one interactions were conducted with 17 children with previous diagnoses of autism. All interactions were videotape and behaviors coded (e.g., eye contact, spontaneous language, aggression, self-injurious behaviors). Professionals reviewed videotapes with specialized training in hearing loss and those without to confirm autism diagnosis. Results: As a whole (n = 52) approximately 50% of the sample did not meet diagnostic criterion on the autism screeners for possible autism, nor meet DSM-IV TR criterion. Scores were also not in the clinical range. One-on-one interactions of children with a previous autism diagnosis did not yield behaviors often associated with autism. Instead many children engaged in reciprocal conversations, initiated conversations, and maintained eye contact for extended periods of time. Review of videotape data also suggested that professionals specializing in hearing loss and those without specialized training did not agree on diagnosis for all children. Children suspected to have an autism diagnosis by professionals trained in hearing loss had significantly higher scores on the SRS, SCQ, and GARS-2 than those without. Scores for those children were within the clinical range and thus consistent with a previous diagnosis of autism. Children suspected of autism by professionals not trained in hearing loss did not have mean scores on the SRS, SCQ, or SCQ that were within the clinical range. Conclusions: Characteristics of autism (e.g., lack of response to name, delays in expressive language, difficulties with socialization) are often considered characteristics of typical development in children with hearing loss. The confusion in presentation of deafness and autism for those professionals not trained in hearing loss may contribute to the lack of consensus of diagnosis. Results may also suggest that conventional screeners for autism may not be valid tools for children with co-morbid hearing loss and suspected autism (approximately 50% of children did not score in the clinical range). It may also be possible to suggest that while autism is believed to have innate genetic causes, external factors such as a child's language (e.g., sign language), hearing status, cultural associations (e.g., member of the deaf community or school), and other unique characteristics (e.g., parents who are also deaf) may directly impact the child and his/her autism, thus causing autism to be expressed differently in these children. Results warrant future research across cultures and co-morbid conditions.