Autistic children are two-and-a- half times more likely to have persistent gastrointestinal symptoms as infants and toddlers, a new study has found.
The study at Columbia University's Mailman School of Public Health is based on a large longitudinal survey of Norwegian mothers who were asked about their child's gastrointestinal (GI) disturbances during the first three years of life.
Questionnaires were completed when the children were 18 and 36 months of age.
Researchers found that children with autism spectrum disorder (ASD) had higher odds of their mothers reporting constipation and food allergy/intolerance in the 6- to 18-month-old age range, and higher odds of diarrhoea, constipation, and food allergy/intolerance in the 18- to 36-month-old age range compared to children with typical development.
Mothers of children with ASD were also more likely to report one or more GI symptoms in their children in either or both age ranges compared with mothers of children with typical development.
Children with ASD were more likely to have GI symptoms than children with developmental delay, suggesting that the disturbances were not simply secondary to developmental delay associated with autism.
"We not only learned that these symptoms appeared early in infancy; we also found that children with ASD were at significantly increased risk for these symptoms to persist compared with typically developing children," said Michaeline Bresnahan, first author and assistant professor of Epidemiology at the Mailman School.
While higher levels of GI symptoms are associated with autism, Bresnahan cautioned that "the vast majority of children with these symptoms won't go on to develop autism, nor do all people with autism have GI problems as children."
Bresnahan added: "GI symptoms alone need not be cause for alarm."
The study is published in the journal JAMA Psychiatry.
