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Study Examines the Prevalence and Impact of Gastrointestinal Problems in Children with Autism

Science Update

A new study examines the characteristics of children with pervasive developmental disorders (PDD) who also have gastrointestinal problems. The study was published online ahead of print September 2008 in the Journal of Autism and Developmental Disorders.

PDDs, such as autism and Asperger’s disorder, are marked by repetitive behavior and pervasive impairments in language and the ability to relate to others. Some studies have suggested a link between PDDs and gastrointestinal (GI) problems such as reflux, stomach pain, bloating, food intolerance, constipation or diarrhea. But epidemiological studies have found no higher prevalence of GI problems among children with PDD compared to normally developing children.

Roumen Nikolov, M.D., Lawrence Scahill, MSN, Ph.D., both of Yale University, and colleagues evaluated baseline data from the 172 children enrolled in the NIMH-funded Research Units on Pediatric Psychopharmacology (RUPP) Autism Network to examine the types and frequency of GI problems among the participants. The RUPP network conducted two major trials. In the first trial children with autism accompanied by tantrums, aggression and self-injury were treated with the antipsychotic risperidone (Risperdal). In the second trial, children with PDD and hyperactivity were treated with the stimulant methylphenidate, which is commonly used to treat attention deficit hyperactivity disorder.

Overall, 22.7 percent of the 172 children had GI problems. In the risperidone study, 29 percent had a history of GI problems compared to 14 percent in the methylphenidate study. The researchers found no demographic differences between the children with GI problems and those without GI problems, nor did the groups differ in communication, socialization, daily living skills, intellectual ability or on measures of autism severity. However, the group with GI problems had more severe anxiety, irritability and social withdrawal.

In the risperidone trial, just over half of the children with GI problems showed a positive response to treatment compared to 75 percent of those with no history of GI problems. There was no difference in the rate of positive response in the methylphenidate trial.

Nikolov and colleagues conclude that the findings of this study do not support the idea  that GI problems are more common in children with PDD or associated with specific characteristics of PDD.  More research is needed to determine how GI problems may be related to PDD.  


Nikolov RN, Bearss KE, Lettinga J, Erickson C, Rodowski M, Aman MG, McCracken JT, McDougle CJ, Tierney E, Vitiello B, Arnold LE, Shah B, Posey DJ, Ritz L, Scahill L. Gastrointestinal symptoms in a sample of children with pervasive developmental disorders. Journal of Autism and Developmental Disorders. Online ahead of print Sept 2008.