A study published in the journal Pediatric Allergy and Immunology suggested that young children with allergies are more likely to develop attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) by the time they are 18. Dr. Shay Nemet, MD, of the Kaplan Medical Center in Rehovot, Israel, and the lead author of the retrospective study, stated that the study provides strong evidence for the association between allergic disorders in early childhood and the development of ADHD.

In the study, children who were diagnosed with one or more allergies between the ages of 0 to 9 years were found to be at a significantly higher risk of developing ADHD (odds ratio [OR], 2.45), ASD (OR, 1.17), or both ADHD and ASD (OR, 1.56) than the children in the control group who did not have any allergies. Also, it was observed that the children diagnosed with rhinitis and conjunctivitis were the most likely to develop ADHD.

Dr. Jordan, MD, FAAP, an Assistant Professor of Pediatrics at UPMC Childrens Hospital of Pittsburgh, Pennsylvania, stated that the study has shown a statistically significant correlation between ADHD, ASD, and allergic conditions. However, the studys retrospective design and the possibility of recall bias are the major limitations of the study that can impact the study findings.

(Source: https://www.medscape.com/viewarticle/976705 )