Connection between allergy and ADHD

News hot off the press!    An association between allergic symptoms and development of ADHD was reported as one of the top stories in Medscape psychiatry on 09 07 22 in Medscape Medical News. This will not be a surprise to you!

A well-conducted study of 117,000 children with at least one allergic disorder, were significantly more likely to develop attention-deficit/ hyperactivity disorder (ADHD) by age 18. The allergic symptoms most likely to be connected were rhinitis, and conjunctivitis. We see them as a constantly runny nose or inflamed eyes. Hay fever is the classic example of these.

Those of us who have researched food sensitivity, which includes allergy, have very often had parents of ADHD children report them having at least one allergic disorder. Others included asthma, drug food or skin allergy. In my early 1991 clinical follow up study done with Connell, Hill, and Reilly we reported on the trialling a low additive low salicylate diet in 516 families as part of management of behavioural and learning problems many with ADHD. In that group 42.4% had allergies. Sixty-eight had a family history of allergy. See on this site: https://foodintolerancepro.com/category/evidence-base/published-report-500-families-1991/

You, as parents, know it requires much effort to well manage both conditions at the same time.

This study “Early Childhood Disorders Linked with ADHD and ASD” was reported by  Lorraine L. Janeczko, MPH in Paediatric Allergy and Immunology. Pediatr Allergy Immunol. Published online June 17, 2022

The risk to develop ASD was also studied but a reviewer, Nadler, who was not involved in the study, noted that in the analysis that controlled for age at study entry, gender, and number of annual visits, the link between allergy and ASD diagnosis did not reach significance level. He adds that “Clinicians practicing in subspecialties such as allergy and immunology may have opportunities to help psychologists identify developmental and behavioural concerns early in childhood”. This also means that parent of children with allergic symptoms should also report them to psychologists who are busy looking at behavioural problems and often not connect allergy as a possibly important part of the child’s behavioural picture. He adds “It is important to remember not to interpret these study results as causal”. This means that the presence of ADHD does not mean that allergies will be present, nor that where allergies are present ADHD may develop.

Another reviewer called the study “an interesting new area that has been speculated about for some time” and “one of the first I have seen with statistically significant correlations found between ADHD, and allergic conditions.” This is great news and we can all hope that it will encourage more researchers to study the connection more.

As more research is done more researchers will understand the role of food chemical sensitivity in this group more. This will means the awareness of other symptoms such as headache, car-sickness and tummy aches as relevant to the bigger picture.