Sensitisation to milk, egg and peanut from birth to 18 years: a longitudinal study of a cohort at risk of allergic disease.

BACKGROUND: Longitudinal data on the natural history of food sensitisation beyond early childhood are scarce. We aimed to investigate the natural history of milk, egg and peanut sensitisation from infancy to18 years and assess whether early food sensitisation predicted adolescent food allergy. METHODS: Sensitisation to cow's milk, hen's egg and peanut was measured by skin prick testing at ages 6 months, 1, 2, 12 and 18 years in a high risk allergy birth cohort (n=620). Generalized additive models investigated interactions with sex, eczema and aeroallergen sensitisation in infancy. Logistic regression assessed the relationships between early food sensitisation and adolescent sensitisation and probable food allergy up to 18 years. RESULTS: The prevalence of egg and peanut sensitisation peaked at 12 months, while milk sensitisation peaked at both 1 and 12 years. Boys with early eczema had the highest prevalences of milk and egg sensitisation throughout follow-ups. However, neither sex nor eczema influenced the prevalence of peanut sensitisation over time. New onset food sensitisation beyond the age of 2 was observed in 7% of participants. Food sensitisation at 12 months was associated with increased risk of adolescent food sensitisation and adolescent probable food allergy, with sensitisation to more than one food allergen had the strongest predictor. CONCLUSIONS: Food sensitisation prevalence is highest in infancy and declines after 12 months of age. Boys with early life eczema have the highest prevalence of milk and egg sensitisation. Food sensitisation at 12 months can predict children at greater risk of adolescent sensitisation and probable food allergy at 12 and 18 years. This article is protected by copyright. All rights reserved.