For years, researchers have documented both gastrointestinal issues and problematic behaviors, such as aggression, in many children with autism spectrum disorder.
Researchers from the University of Missouri have now found that both internalizing and externalizing problem behaviors might indicate gastrointestinal distress in children and adolescents with autism.
Bradley Ferguson, assistant research professor in the departments of health psychology, radiology, and the Thompson Center for Autism & Neurodevelopmental Disorders, examined records from 340 children and adolescents with autism who are patients at the Thompson Center. Ferguson found that 65% of patients experienced constipation, nearly half experienced stomach pain, nearly 30% experienced diarrhea and 23% experienced nausea. Furthermore, some of these gastrointestinal symptoms were associated with different behaviors, such as anxiety and aggression.
"We are starting to better understand how gastrointestinal issues coincide with problem behaviors in ASD," Ferguson said. "For example, we found that individuals with autism and co-occurring nausea were about 11% more likely to display aggressive behaviors. Therefore, addressing the nausea might alleviate the aggressive behaviors which will ultimately increase the quality of life for the patient as well as their family."
One in 59 children in the United States is diagnosed with autism spectrum disorder. Since the developmental disorder can affect an individual's social skills, speech, and nonverbal communication, it can be difficult for those with the disorder to adequately communicate other health challenges, such as gastrointestinal discomfort.
Ferguson and his colleagues also found that the relationship between problem behaviors and gastrointestinal symptoms differed between young children and older children with autism. While aggressive behavior in younger children, aged 2-5, was associated with upper gastrointestinal issues such as nausea and stomach pains, older children, aged 6-18, with greater anxiety were more likely to experience lower gastrointestinal issues such as constipation and diarrhea. Understanding these differences can help shape future treatments for individuals with ASD.
"These findings further highlight the importance of treating gastrointestinal issues in autism," Ferguson said. "Many children and adolescents with autism spectrum disorder are often unable to verbally communicate their discomfort, which can lead to problem behavior as a means of communicating their discomfort."
Ferguson noted that since the study is correlational in nature, it is not yet clear if the gastrointestinal symptoms are causing the problem behavior or vice versa.
"Regardless, our team is examining the effects of propranolol, a beta blocker with stress-blocking effects, on constipation and other symptoms. We have to work quickly, because people are suffering and need answers now. We hope that our research will translate to better quality of life," he said.