Food allergies in children less frequent than expected

Food allergies among 6- to 10-year-olds may be less common than previously reported, researchers found in a multinational study of European school-age children.

The prevalence was as low as 1.4% and as high as 3.8% using different research methods, and most likely falls somewhere in between. The findings were “considerably lower” than the 16% rate based on parental reports of symptoms such as rash, itching, or diarrhea, Linus Grabenhenrich, MD, MPH, and colleagues reported in Allergy.

In addition, peanut and hazelnut allergens were most common among the 223 children with a positive skin prick allergy assay. A total 5.6% tested sensitive to peanuts and 5.2% to hazelnuts.

Previous research reports of pediatric food allergy prevalence were largely single-center studies with heterogeneous designs, the researchers noted. These prior protocols make comparisons across countries challenging.

In search of a more definitive answer, Dr. Grabenhenrich, of the Robert Koch-Institut in Berlin, and colleagues evaluated 238 children. This group was about 10% of 2,288 children with parental face-to-face interviews and/or skin prick testing from a birth cohort in Germany, Greece, Iceland, Lithuania, the Netherlands, Poland, Spain, and United Kingdom called the EuroPrevall-iFAAM.

All participants had suspected food allergies, and the mean age at follow-up was 8 years. A total 46 children participated in a double-blind, placebo-controlled oral food allergy challenge (DBPCFC). “Most of the positively challenged children reacted only mildly or moderately, except for five children with severe signs or symptoms during DBPCFC,” Dr. Grabenhenrich and associates noted.

A food allergy to at least one allergen was confirmed in 17 children out of 2,097 who completed assessment. This yielded an average raw prevalence of 0.8% across all eight countries. The estimated 1.4%-3.8% food allergy prevalence was based on adjusted analyses that extrapolated findings to all children with questionnaire data or who completed an eligibility assessment.

“Considerable attrition” in all stages of the assessment was a potential limitation. In addition, 192 parents refused to participate in the DBPCFC food challenge component of the research. Studying a birth cohort across European countries was a study strength.

The European Commission supported this study. Dr. Grabenhenrich had no relevant disclosures. Some coauthors reported various ties to pharmaceutical and food companies.

SOURCE: Grabenhenrich L et al. Allergy. 2020 Mar 27. doi: 10.1111/all.14290.