Gastrointestinal problems are associated with increased repetitive behaviors but not social communication difficulties in young children with autism spectrum disorders

Abstract

Individuals with autism spectrum disorder are more likely than typically developing individuals to experience a range of gastrointestinal abnormalities, including chronic diarrhea, constipation, food sensitivities, and abdominal pain. These gastrointestinal symptoms have been associated with higher levels of irritability and aggressive behavior, but less is known about their relationship with core autism spectrum disorder symptoms. We investigated the relationship between autism spectrum disorder and gastrointestinal symptom severity while accounting for three associated behavioral symptom domains (Irritability, Aggressiveness, and Specific Fears), in a sample of 176 children (140 males and 36 females) ages 2–7 years old with autism spectrum disorder. Most participants had at least one reported gastrointestinal symptom (93.2%) and had more than one gastrointestinal symptom (88.1%). After accounting for each associated behavioral symptom domain, repetitive behaviors and stereotypies were positively associated with gastrointestinal symptom severity. Social and communication difficulties were not significantly associated with gastrointestinal symptom severity after accounting for associated behavioral symptoms. Our findings replicate a previously described association between irritability and aggression and gastrointestinal symptoms. Furthermore, gastrointestinal symptom severity is associated with repetitive behaviors, a subset of core autism spectrum disorder symptoms. This suggests that gastrointestinal symptoms may exacerbate repetitive behaviors, or vice versa, independent from other associated behavioral symptoms. Lay Abstract Individuals with autism spectrum disorder are more likely than typically developing individuals to experience a range of gastrointestinal abnormalities, including chronic diarrhea, constipation, food sensitivities, and abdominal pain. These gastrointestinal symptoms have been associated with higher levels of irritability and aggressive behavior, but less is known about their relationship with core autism spectrum disorder symptoms. We investigated the relationship between autism spectrum disorder symptom severity and gastrointestinal symptoms while accounting for three associated behavioral symptom domains (Irritability, Aggressiveness, and Specific Fears), in a sample of 176 children (140 males and 36 females) ages 2–7 years old with autism spectrum disorder. A large majority (93.2%) of the sample had at least one reported gastrointestinal symptom, and most (88.1%) participants had more than one gastrointestinal symptom. Various types of gastrointestinal symptoms were reported; the most common symptoms reported were constipation, food limits, gas/bloating, and stomach pain. After accounting for each associated behavioral symptom domain, repetitive behaviors and stereotypies were significantly associated with gastrointestinal symptom severity. Increased severity of autism spectrum disorder symptoms was correlated with increased gastrointestinal symptom severity. Social and communication difficulties were not significantly associated with gastrointestinal symptom severity after accounting for associated behavioral symptoms. Our findings replicate a previously described association between irritability and aggression and gastrointestinal symptoms. Furthermore, we found that repetitive behaviors, but not social or communication symptoms, are associated with gastrointestinal symptom severity, even after accounting for associated behavioral symptoms. This suggests that gastrointestinal symptoms may exacerbate repetitive behaviors, or vice versa, independent from other associated behavioral symptoms.

Exploration of Relationships among Clinical Gastrointestinal Indicators and Social and Sensory Symptom Severity in Children with Autism Spectrum Disorder

“…However, the multiple regression model of SRS-2 scores using the three clinical GI variables was not found to be statistically significant, perhaps due to limited sample size.. Abdominal pain significantly contributed to the SRS-2 outcome, thus providing evidence of its strong relationship to severity of social symptoms. This finding is consistent with other studies that have reported relationships between GI symptoms and severity of specific ASD symptoms, including social withdrawal [ 20 , 24 ], anxiety [ 20 , 25 ], repetitive behaviors and stereotypes [ 26 ], expressive language deficits [ 27 ], sleep problems [ 28 ], and sensory sensitivity [ 25 ].…”

“…For the children with GI symptomatology of abdominal pain and/or atypical stools, greater social and sensory symptom severity was observed. These findings extend understanding of results from other studies that have examined psychological and behavioral impacts of frequent GI symptomatology—specifically, studies reporting strong correlations among GI symptomatology, sociability, and behavioral symptoms in children with ASD (e.g., [ 26 , 31 , 32 ]). These findings are also consistent with those from researchers who have found severely restricted behaviors in ASD, such as rigid and compulsive behaviors, to be associated with functional constipation [ 33 ] and diarrhea [ 34 ].…”

Comparison of Autistic Individuals Who Engage in Self-Injurious Behavior, Aggression, and Both Behaviors

“…Unexpectedly, those who did not engage in either SIB or aggression were more likely to experience GI problems such as constipation and diarrhea. Other researchers have reported a relationship between GI issues and challenging behaviors [7,21], whereas Maenner, Arneson, Levy, Kirby, and Nicholas et al [22] reported that aggressive behaviors were common in those both with and without GI problems in a large-scale study of children with ASD.…”

The gut-microbiota-brain axis in autism: what Drosophila models can offer?

“…As mentioned earlier, ASD is associated with a range of chronic GI symptoms, including altered bowel habits, abdominal pain, and food intolerance [ 37 ]. Gut distress or abdominal discomfort can give rise to behavioral difficulties and potentiate ASD’s core stereotypical behaviors, like mouthing gestures, screaming, and self-injury to the abdomen to relieve pain [ 35 ]. However, because of communicative defects in ASD patients, GI issues often remain undiagnosed and hence untreated.…”