By Amy Tong

Gastrointestinal Symptoms in Adults with Autism Spectrum Disorders: The Mediating Effects of Anxiety and Gastrointestinal Fear 

Study Overview 

  • This study aimed to investigate the link between anxiety and GI symptoms in autistic adults. 
  • Data was collected as part of a survey of 154 adults, either with an autism diagnosis (n = 70) or without (n = 84), measuring autistic traits, GI symptoms, and general anxiety. 

Why is this research needed? 

  • Autistic adults are at increased risk of developing gastrointestinal (GI) disorders, with prevalence rates estimated between 30-70% (Penzol et al., 2019) .  
  • These co-occurring GI disorders have a signicant impact on quality of life  (Mannion & Leader, 2014). 
  • It is unclear why the rates of GI disorders are higher in autism compared to the neurotypical population. 
  • One potential mechanism is co-occurring anxiety symptoms. Anxiety is known to increase the risk of GI disorders in the general population (Van Oudenhove et al., 2016). Given that anxiety disorders are common in autism, we sought to investigate whether autism or co-occurring anxiety symptoms drive GI disorder risk. 


  • As expected, higher levels of autistic traits were related to more severe GI symptoms and higher levels of anxiety. 
  • A mediation analysis showed that increased anxiety partially explained the relationship between autistic traits and GI symptoms across the autism spectrum – i.e., Autism is related to GI symptoms through increased anxiety. 


  • The high prevalence of GI symptoms in autism may be partially explained by higher levels of anxiety. 

If you have any questions regarding this study, please direct them to 


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