Association between gut microbiota and Autism Spectrum Disorder; a systematic review and meta-analysis

The Publication

Autism spectrum disorder (ASD) is a neurodevelopmental disorder which presents in a wide range of ways, with persistent challenges in speech, non-verbal communication and social interaction. Gastrointestinal dysfunction is a common symptom associated with ASD; suggesting there is a potential link between the gut microbiota and ASD pathophysiology. Research has highlighted that people with autism present with alterations in their gut microbiota. However, there is limited research on the specific bacterial species that are altered in these individuals.

This systematic review collated evidence from different studies to compare the changes in abundance of bacterial genera in individuals with ASD and those without. Results showed disparity in microbial composition; high abundance of bacteria involved in immunity dysfunction being significant higher for people with ASD, yet lower levels of beneficial bacteria. This is significant, because balance of microbial populations and their metabolites are crucial for maintaining white matter and epithelial barrier integrity, essential for normal brain development and function. Furthermore, the development of the blood brain barrier is dependent on the presence of commensal flora within the microbiota.

Our Response

The role that the microbiota has in the development of autism is yet to be established. However, potential mechanisms suggest that disruptions to the microbiome could initiate inflammatory processes, altering metabolic pathways and subsequently influence behaviour. Knowing that omega-3s can improve both our inflammatory status and the diversity of our microbiome, it would be interesting to assess the effect of early life supplementation in prevention, management or mitigation of ASD disease progression.