More Tummy Troubles for Kids with Autism

Gastrointestinal symptoms may be more common in autism patients

(RxWiki News) Caring for a child with autism comes with struggles, and many parents may find that stomach problems in kids may be part of those struggles.

A new study found that mothers whose children had been diagnosed with autism reported more gastrointestinal (GI) symptoms in their children in the first three years of life. This study compared children diagnosed with autism to children with developmental delays and children who displayed typical development.

The authors of this study were careful to note that their findings don't mean that there's a cause-and-effect relationship between autism and GI symptoms.

Crystal Beadle, PhD, a licensed neuropsychologist at Our Children's House at Baylor in Frisco, TX, echoed that sentiment.

"There is no definitive scientific link between food intolerance or other GI symptoms and autism at this time," Dr. Beadle, who was not involved with the current study, told dailyRx News. "However, there is overwhelming evidence of significantly increased comorbidity between food intolerance, GI symptoms, picky eating, and autism. Several studies have shown reported behavioral improvement when children with autism spectrum disorder (ASD) are placed on either a gluten-free, casein-free, yeast-free, or other 'limited' diet."

Dr. Beadle continued, "However, there are just as many 'negative studies' showing no improvement for children with [autism spectrum disorders] when treated with dietary modifications or restrictions. This has been interpreted to show there is no link between autism and food intolerance or GI symptoms. So, no, there is no agreed-upon scientific link between autism and food intolerance or gut symptoms at this time."

"Even though GI symptoms are common in early childhood, physicians should be mindful that children with autism may be experiencing more GI difficulties in the first 3 years of life than children with typical development and developmental delays," the authors of this study wrote. "Furthermore, the GI symptoms may be more persistent in children with autism. The potential for underrecognition and undertreatment of GI dysfunction in the context of a complicated developmental picture is real. Treatments that address GI symptoms may significantly contribute to the well-being of children with autism and may be useful in reducing difficult behaviors."

Michaeline Bresnahan, PhD, of Columbia University in New York City, led this study.

Dr. Bresnahan and team noted that GI problems are known to coexist with autism.

Autism is a group of conditions marked by problems with social interactions or repetitive behaviors. This group is referred to as autism spectrum disorders, or ASD.

This study was designed to determine when the GI symptoms first appear and how the children with ASD compared to other children.

Dr. Bresnahan and team used data from a Norwegian study that looked at over 45,000 children. These children were placed into three groups.

The smallest group included 195 children who had autism. The second group was children who had developmental delays, or who did not learn to walk and talk normally.

The third and largest group included children who developed normally.

The data on GI symptoms came from mothers’ reports of their children in the first three years of life. Among the common symptoms were constipation, diarrhea, and food allergies or intolerance.

When compared to children with normal development, children with ASD were more likely to have constipation and food intolerance between the ages of 6 and 8 months. Children with ASD also had more diarrhea, constipation and food intolerance in the 18- to 36-month-old range.

Children with ASD also had more GI symptoms than children with developmental delays.

"Studies have shown an increase in two particular bacteria (Clostridium and Desulfovibrio) in children with ASD at a much higher rate than children without ASD, though both groups reported similar GI complaints," Dr. Beadle said. "There have also been limited case studies (with only anecdotal evidence, which should be interpreted with caution) reporting significant behavioral improvement when children with ASD have fevers, take antibiotics, and when given probiotics, all which reduce the level of bacteria in the gut. These studies would suggest a link between the gut microbiome and autism."

Dr. Beadle added, "Again, though, there is no evidence of one causing the other. Many (if not most) children with ASD are picky eaters, often extremely limited in their food choices. This behavioral implication of ASD may alter the gut microbiome, further exacerbating the symptoms of ASD already present. Or, the altered microbiome may lead to the child’s behaviors and/or unwillingness to consume or lack of desire for particular foods. There is a link, but the causal nature of the link is still not clear."

Dr. Beadle said parents should be aware of their children's particular nutritional and behavioral needs.

"It would be wise for the parents of children with ASD to work in a cooperative nature with a team of specialists, including behavioral support, nutritionists, gastroenterologists, and other therapists, particularly when the child has GI complaints or food intolerances," Dr. Beadle said. "Though there is no hard-core evidence to support the link between food intolerance and autism symptomology at this point, there is also not overwhelming evidence that it never is beneficial.

"The research seems to be very mixed still. Because ASD is such a spectrum disorder in that no two cases of autism present exactly the same, it is likely there are subtypes of autism that are more sensitive (perhaps even caused by or more closely related to) food sensitivities and microbiome changes. The research simply has not taught us enough yet to fully make those distinctions. I would encourage parents to go with their instincts, under the supervision of the medical team — if they see positive changes in their child with dietary changes, and the child is maintaining adequate health and nutrition, then the family has found a beneficial change for their child."

Dr. Beadle concluded by saying that parents of children with autism should take a cautious approach because the current research "does not support a one-size-fits-all approach to dietary management of ASD."

This study was published March 25 in JAMA Psychiatry.

The Norwegian Ministry of Health and Care Services, the Norwegian Ministry of Education and Research, the National Institutes of Health and the Research Council of Norway funded this research. Dr. Bresnahan and team disclosed no conflicts of interest.

Review Date: 
March 24, 2015