Is Autism a Disease?

Autism spectrum disorders have formerly been defined as a group of neurodevelopmental disorders that include “Asperger's syndrome, Rett syndrome, childhood disintegrative disorder, and pervasive developmental disorder not otherwise specified” [1]. Asperger’s syndrome, childhood disintegrative disorder, and pervasive developmental disorder are placed under autism spectrum disorder (ASD) in the upcoming DSM-V [1]. On the other hand, Rett syndrome has been removed from the DSM [1]. “Deficits in social skills and communication, stereotyped and repetitive behavior, and a range of cognitive deficits” are usual symptoms within the ASD spectrum, which are typically diagnosed by 4.8 years of age [1]. However, such symptoms have been detected as early as six months of age [1].

Environmental insults during pregnancy or post-pregnancy may also cause autism. In early development, the brain is more vulnerable to environmental damage [1]. Environmental factors, including the exposure to specific toxins, can cause neuropsychological deficits closely resembling autism [1]. Many environmental factors have been explicitly identified as causing “both autistic symptoms and an increased likelihood of a diagnosis of autism” [1]. However, exposure to environmental agents is not the sole cause of autism. Genetic factors account for most cases. Therefore, autism is likely the result of a combination of genetic predispositions and environmental insults. The degree of severity of the phenotype may depend on the severity of the genetic predispositions and environmental insults [1].

Changing diagnostic criteria with the new diagnostic manual (DSM-5) may impact prevalence rates, which are currently 1 in 59 children in the United States [2]. ASD is defined as a “neurobiological condition caused by both genetic and environment factors affecting the developing brain” [2]. Researchers continue to discover factors associated with ASD risk, and these findings may guide the further etiological investigation, but no final causal pathway has been established [2]. Children are first screened at the pediatric level, and then are referred to a specialist for a proper assessment and diagnosis if deemed to be at-risk for ASD [2]. Co-morbid disorders should also be checked in children with ASD [2]. Clinical genetic testing is recommended during the initial medical evaluation, regardless of whether there are precise biomarkers or diagnostic measures [2]. Further medical examinations or referrals to subspecialists may be recommended [2].

References

1. Rogers, T. D., McKimm, E., Dickson, P. E., Goldowitz, D., Blaha, C. D., & Mittleman, G. (2013, May 13). Is autism a disease of the cerebellum? an integration of clinical and pre-clinical research. Frontiers. Retrieved February 19, 2022, from https://www.frontiersin.org/articles/10.3389/fnsys.2013.00015/full

2. Hodges, H., Fealko, C., & Soares, N. (2020, February). Autism spectrum disorder: Definition, epidemiology, causes, and clinical evaluation. Translational pediatrics. Retrieved February 19, 2022, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7082249/

Contributors:

Author: Rayven Hall

Editor: Sara Giarnieri

Health scientist: Rayven Hall

@werise4wellness