Autism & Developmental

Diseases of the gastrointestinal tract in individuals diagnosed as children with atypical autism: a Danish register study based on hospital diagnoses.

Mouridsen et al. (2013) · Autism : the international journal of research and practice 2013
★ The Verdict

Adults with atypical autism carry no extra GI disease risk, so treat stomach issues the same way you would for anyone else.

✓ Read this if BCBAs who field parent questions about special diets or gut protocols for autistic teens and adults.
✗ Skip if Clinicians working only with non-verbal young children where GI pain may show as behavior spikes.

01Research in Context

01

What this study did

Danish doctors tracked adults who had been diagnosed with atypical autism as kids. They checked hospital records for gut diseases up to 33 years later.

The team compared the group to the general public to see if autism raised stomach risk.

02

What they found

About one in four adults from both groups had a gut disease. The numbers were too close to call it a real difference.

In plain words, atypical autism did not hike later GI trouble.

03

How this fits with other research

A 2005 review already said proof for special gut issues in autism was weak. The new long-term data backs that up.

Holingue et al. (2023) asked parents of autistic kids about tummy pain. Parents of kids with ID doubted vague complaints but agreed on clear signs like constipation. That survey and this register study both warn against over-blaming autism for every stomach ache.

Wang et al. (2025) pooled millions of families and found Mom or Dad’s IBD did not raise autism odds. Together with Mouridsen et al. (2013), the picture is quiet: autism and gut disease are not tightly linked in either direction.

04

Why it matters

You can reassure families that most autistic adults do not face extra GI disease. Focus your teaching on common-sense diet, hydration, and toileting plans instead of hunting for autism-specific gut problems. If a client reports pain, look for the same causes you would check in any adult.

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Drop the phrase “autism gut troubles” from parent talks; teach fiber, water, and regular toilet times instead.

02At a glance

Intervention
not applicable
Design
quasi experimental
Sample size
89
Population
autism spectrum disorder
Finding
null
Magnitude
negligible

03Original abstract

The purpose of this study is to compare the prevalence and types of diseases (International classification of mental and behavioural disorders, 10th edition codes K20-K93) relating to the gastrointestinal tract in a clinical sample of 89 individuals diagnosed as children with atypical autism/pervasive developmental disorder not otherwise specified with 258 controls from the general population. All participants were screened through the nationwide Danish National Hospital Register. The average observation time was 32.9 years, and mean age at the end of the observation period was 48.5 years. Among the 89 cases with atypical autism, a total of 22 (24.7%) were registered with at least one diagnosis of any disease of the gastrointestinal tract, against 47 of 258 (18.2%) in the comparison group (p = 0.22; odds ratio = 1.5; 95% confidence interval = 0.8-2.6). Without reaching statistical significance, the rate of diseases of the gastrointestinal tract was particularly high (odds ratio = 1.2) in those with intelligence quotient < 70. Overall, people with atypical autism had about the same frequency of gastric, intestinal and hepatic diseases as had controls.

Autism : the international journal of research and practice, 2013 · doi:10.1177/1362361312455110