When it comes to autism, people tend to imagine a kid who is un-responsive and absorbed in his/her thoughts or busy arranging puzzles in a certain way. Nevertheless, the condition is far more than that. Autism refers to a brain development disorder causing altered social interactions, communication issues, as well as repetitive, restricted, and stereotypic behavior patterns, interests and activities of the affected individual.
Autism is a fast-growing developmental disorder globally. In the 1970s and 1980s, about 1 out of every 2,000 children had autism. At present, the Centers for Disease Control and Prevention (CDC) estimates that 1 in 150 8-year-olds in the U.S. has an autism spectrum disorder or ASD. Autism has no single cause. Studies suggest that both genetics and environment play a role.
A new study from researchers at the University of Iowa reveals that kids with ASD are twice as likely to have food allergies as kids without the condition. To find a link between food allergy and autism, the researchers analyzed 199,520 children aged from 3 to 17 who participated in the U.S. National Health Interview Survey from 1997 to 2016.
It was found that out of the 1,868 children with autism, 216 of them or about 11 percent had a food allergy. Only 4 percent of the children without autism had a food allergy. “It is possible that the immunologic disruptions may have processes beginning early in life, which then influence brain development and social functioning, leading to the development of ASD,” said Wei Bao, assistant professor of epidemiology at the UI College of Public Health and corresponding author of the study.
Bao says that earlier studies on the linkage between allergic conditions with ASD were concentrated mainly on respiratory allergy and skin allergy, which had yielded inconsistent and inconclusive results. The new study found about 18 percent of children with ASD suffered from respiratory allergies, while about 12 percent of children without ASD had such allergies; and around 16 percent of children with ASD had skin allergies while nearly 10 percent of children without ASD had such allergies.
Based on the studies, Bao said that there could be a shared mechanism linking various allergic conditions to ASD. He also said that the way that the conditions interact or if one causes the other condition is still unclear.
According to earlier studies, children are at a greater risk of having ASD if their families have a history of type 1 diabetes or rheumatoid arthritis, or in case the mother has immunological issues during pregnancy.
There have been numerous studies performed earlier to find out the connection between allergies and autism; however, none of them have found a strong reason that supports the fact that allergies are implicated in the development of autism disorders or vice-versa.
Hence the researchers said that connection calls for further examination. “A future study that prospectively collects data on the timing of onset for food allergy and autism is needed to establish the temporal relationship between these two conditions,” Bao told the American Journal of Managed Care.
The study, “Association of Food Allergy and Other Allergic Conditions with Autism Spectrum Disorder in Children,” was published online in JAMA Network Open in June 2018.