Published online: May 14, 2017
Allergic diseases have risen in prevalence over the last several decades and are now recognised as a significant public health burden. In recent years, several population-derived prevalence studies on food allergy in infants using gold standard challenge-proven outcomes have emerged, however prevalence estimates in preschool aged children are lacking. The HealthNuts study in Australia was one of the first studies to use a population-based sampling frame and systematic approach to measuring food allergy using oral food challenges (OFC), and in an interim report on the first half of the cohort (n=2800) reported the highest prevalence of food allergy internationally. In a recently published article the in The Journal of Allergy and Clinical Immunology (JACI) Peters and colleagues reported the prevalence of food allergy at age 1 year from the whole cohort, and the prevalence of food allergy and other allergic diseases in 4-year-old children
The HealthNuts study recruited and administered skin prick tests (SPT) to 5276 one-year-old children; any child with detectable SPT results underwent OFC to test for food allergy. The first longitudinal follow-up on the entire cohort commenced when the children turned 4 years of age. Parents were invited to complete a questionnaire which included questions on asthma, eczema, and allergic rhinitis from the validated International Study of Asthma and Allergies in Childhood. Children who were food allergic at age 1 year and those who reported symptoms of a new food allergy were invited for an assessment that included SPT and OFC.
Overall, 11.0% of children had a challenge-confirmed food allergy at age 1 year, and this reduced to 3.8% at age 4 years. Peanut allergy was the most common food allergy at age 4 years with a prevalence of 1.9%, followed by egg allergy at 1.2%. At age 4 years, the prevalence of current asthma was 10.8%, current eczema was 16.0% and current allergic rhinitis was 8.3%, although a higher proportion were reported to have been diagnosed with asthma or eczema ever. Overall, 40-50% of this population-based cohort experienced symptoms of at least one allergic disease in the first 4 years of their life.
Although the prevalence of food allergy decreased between age 1 year and age 4 years in this population-based cohort, the prevalence of food allergy and any allergic disease among 4-year-old children in Melbourne, Australia, is remarkably high.
The Journal of Allergy and Clinical Immunology (JACI) is an official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.