Atopic dermatitis at preschool age and contact allergy in adolescence: a population‐based cohort study

Summary Background Atopic dermatitis (AD) is characterized by an impaired skin barrier, which can allow enhanced penetration of allergens. It is not clear whether AD influences the risk of developing contact allergy. Objectives To examine the association between AD at preschool age and contact allergy at 16 years of age. Methods At 16 years of age, 2215 adolescents from the population‐based cohort BAMSE were included. These adolescents had been followed with repeated questionnaires regarding AD throughout childhood, and contact allergy was assessed by skin patch test at 16 years. Results AD at preschool age was associated with contact allergy to at least one of the tested substances at 16 years of age among boys [adjusted odds ratio (OR) 1·51, 95% confidence interval (CI) 1·03–2·20] but not among girls (adjusted OR 0·77, 95% CI 0·54–1·10). AD at preschool age was not associated with contact allergy to nickel in either boys or girls. In contrast, AD at preschool age was associated with contact allergy to fragrance mix I (adjusted OR 3·10, 95% CI 1·66–5·80). This association was observed especially for AD at preschool age in combination with IgE sensitization to airborne or food allergens (adjusted OR 3·80, 95% CI 1·67–8·61). Conclusions The results suggest that AD in early childhood may be associated with contact allergy to fragrances, but not to nickel, in adolescence. What's already known about this topic? Atopic dermatitis (AD) is characterized by an impaired skin barrier, which can allow penetration of allergens. Children with AD in early childhood may be frequently exposed to contact allergens through topical treatments, such as moisturizers and topical medicaments. What does this study add? AD at preschool age was not associated with contact allergy to nickel in adolescence. Our results indicate that AD at preschool age may be associated with contact allergy to fragrances in adolescence. Avoidance of skin exposure to scented products containing fragrance substances seems warranted in children with AD in early childhood. Linked Comment: Goldenberg and Jacob. Br J Dermatol 2019; 180:704–705. Respond to this article Plain language summary available online