The prevalence of food allergy and other allergic diseases in early childhood in a population-based study: HealthNuts age 4-year follow-up.
BACKGROUND
The HealthNuts study previously reported interim prevalence data showing the highest prevalence of challenge-confirmed food allergy in infants internationally. However, population-derived prevalence data on challenge-confirmed food allergy and other allergic diseases in preschool-aged children remain sparse.


OBJECTIVE
This study aimed to report the updated prevalence of food allergy at age 1 year from the whole cohort, and to report the prevalence of food allergy, asthma, eczema, and allergic rhinitis at age 4 years.


METHODS
HealthNuts is a population-based cohort study with baseline recruitment of 5276 one-year-old children who underwent skin prick test (SPT) to 4 food allergens and those with detectable SPT results had formal food challenges. At age 4 years, parents completed a questionnaire (81.3% completed) and those who previously attended the HealthNuts clinic at age 1 year or reported symptoms of a new food allergy were invited for an assessment that included SPT and oral food challenges. Data on asthma, eczema, and allergic rhinitis were captured by validated International Study of Asthma and Allergies in Childhood questionnaires.


RESULTS
The prevalence of challenge-confirmed food allergy at age 1 and 4 years was 11.0% and 3.8%, respectively. At age 4 years, peanut allergy prevalence was 1.9% (95% CI, 1.6% to 2.3%), egg allergy was 1.2% (95% CI, 0.9% to 1.6%), and sesame allergy was 0.4% (95% CI, 0.3% to 0.6%). Late-onset peanut allergy at age 4 years was rare (0.2%). The prevalence of current asthma was 10.8% (95% CI, 9.7% to 12.1%), current eczema was 16.0% (95% CI, 14.7% to 17.4%), and current allergic rhinitis was 8.3% (95% CI, 7.2% to 9.4%). Forty percent to 50% of this population-based cohort experienced symptoms of an allergic disease in the first 4 years of their life.


CONCLUSIONS
Although the prevalence of food allergy decreased between age 1 year and age 4 years in this population-based cohort, the prevalence of any allergic disease among 4-year-old children in Melbourne, Australia, is remarkably high.
['Peters|Rachel L|RL|', 'Koplin|Jennifer J|JJ|', 'Gurrin|Lyle C|LC|', 'Dharmage|Shyamali C|SC|', 'Wake|Melissa|M|', 'Ponsonby|Anne-Louise|AL|', 'Tang|Mimi L K|MLK|', 'Lowe|Adrian J|AJ|', 'Matheson|Melanie|M|', 'Dwyer|Terence|T|', 'Allen|Katrina J|KJ|', '|||']
D000485:Allergens D000818:Animals D010367:Arachis D001249:Asthma D001315:Australia D002675:Child, Preschool D004485:Eczema D005260:Female D005500:Follow-Up Studies D005512:Food Hypersensitivity D006801:Humans D007223:Infant D008297:Male D008892:Milk D010063:Ovum D015995:Prevalence D065631:Rhinitis, Allergic D017747:Seafood D031685:Sesamum D012882:Skin Tests D011795:Surveys and Questionnaires
prevalence food allergy Allergy population-based study HealthNuts asthma eczema allergic rhinitis peanut allergy egg allergy sesame allergy longitudinal study