Scientists at Columbia University's Mailman School of Public Health report that children with autism spectrum disorder (ASD) were two-and-a-half times more likely to have persistent gastrointestinal (GI) symptoms as infants and toddlers than children with typical development. Results are published in JAMA Psychiatry.
The study is based on a large longitudinal survey of Norwegian mothers who were asked about their child's GI disturbances during the first three years of life. Questionnaires were completed when the children were 18 and 36 months of age.
The authors found that children with 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 diarrhea, constipation, and food allergy/intolerance in the 18- to 36-month-old age range compared with 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. And 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," says Michaeline Bresnahan, PhD, first author and assistant professor of Epidemiology at the Mailman School.
"The longitudinal nature of the study allowed us to uncover the presence of GI complaints in early life--before mothers knew their child would be diagnosed with autism," says Ezra Susser, MD, DrPH, co-senior author and professor of both Psychiatry and Epidemiology at the Mailman School and Columbia University Medical Center. "This is yet another demonstration of how longitudinal cohort research can shed light on features of autism."
GI-Autism Relationship Remains Unclear
While higher levels of GI symptoms are associated with autism, Dr. Bresnahan cautions 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 adds, "GI symptoms alone need not be cause for alarm."
"Although the connection of GI disturbances to autism remains unclear, the presence of GI symptoms in early life may not only help to identify a subset of children with autism who require clinical input for their GI issues, it may also open new avenues for determining the underlying nature of the disorder in that subgroup," notes Mady Hornig, MD, co-first author of the study and associate professor of Epidemiology at the Mailman School.
"Delineating factors that disrupt signaling along the gut-brain axis while the brain is still under development may ultimately provide a key to understanding how the disorder occurs in the subset of children with autism and GI complaints," adds W. Ian Lipkin, MD, the study's senior author, and John Snow professor of Epidemiology and director of the Center for Infection and Immunity at the Mailman School.
Additional co-authors include Andrew F. Schultz from the Mailman School; Nina Gunnes, Kari Kveim Lie, Per Magnus, Ted Reichborn-Kjennerud, Christine Roth, Synnve Schjølberg, Camilla Stoltenberg and Pål Surén from the Norwegian Institute of Public Health; and Deborah Hirtz from the National Institute of Neurological Disorders and Stroke.
The research was supported by the Norwegian Ministry of Health and Care Service, the Norwegian Ministry of Education and Research, and grant NS47537 from the National Institute of Neurological Disorders and Stroke of the National Institutes of Health. The authors report no conflicts of interest.
About Columbia University's Mailman School of Public Health
Founded in 1922, Columbia University's Mailman School of Public Health pursues an agenda of research, education, and service to address the critical and complex public health issues affecting New Yorkers, the nation and the world. The Mailman School is the third largest recipient of NIH grants among schools of public health. Its over 450 multi-disciplinary faculty members work in more than 100 countries around the world, addressing such issues as preventing infectious and chronic diseases, environmental health, maternal and child health, health policy, climate change & health, and public health preparedness. It is a leader in public health education with over 1,300 graduate students from more than 40 nations pursuing a variety of master's and doctoral degree programs. The Mailman School is also home to numerous world-renowned research centers including ICAP (formerly the International Center for AIDS Care and Treatment Programs) and the Center for Infection and Immunity. For more information, please visit http://www.