Prevalence of atopic dermatitis, asthma, allergic rhinitis, and hand and contact dermatitis in adolescents. The Odense Adolescence Cohort Study on Atopic Diseases and Dermatitis

Background Atopic diseases are common in children and adolescents. However, epidemiological knowledge is sparse for hand eczema and allergic contact d ermatitis in this age group. Furthermore, no population-based studies have evaluated the prevalence of atopic diseases and hand and contact dermatitis in the same group of adolescents. Objectives To assess prevalence measures of atopic dermatitis (AD), asthma, allergic rhinitis and hand and contact dermatitis in adolescents in Odense municipality Denmark. Methods The study was carried out as a cross-sectional study among 1501 eig hth grade school children (age 12-16 years) and included questionnaire, int erview, clinical examination and patch testing. Results The lifetime prevalence of AD was 21.3%.(girls 25.7% vs. boys 17.0% , P < 0.001) using predefined questionnaire criteria. The 1-year period pre valence of AD was 6.7% and the point prevalence 3.6% (Hanifin and Rajka cri teria). In the interview the lifetime prevalence of inhalant allergy was es timated as 17.7% (6.9% allergic asthma, 15.7% allergic rhinitis). The lifet ime prevalence of hand eczema based on the questionnaire was 9.2%, the I-ye ar period prevalence was 7.3% and the point prevalence 3.2%, with a signifi cant predominance in girls. A significant association was found both betwee n AD and inhalant allergy, and between AD and hand eczema using lifetime pr evalence measures. The point prevalence of contact allergy was 15.2% (girls 19.4% vs. boys 10.3%, P < 0.001), and present or past allergic contact der matitis was found in 7.2% (girls 11.3% vs. boys 2.5%). Contact allergy was most common to nickel (8.6%) and fragrance mix (1.8%). Conclusions High prevalence figures were found for atopic diseases, hand ec zema and allergic contact dermatitis, and the diseases were closely associa ted. A considerable number of adolescents still suffers from AD, and a cons iderable sex difference was noted for hand eczema and allergic contact derm atitis. Nickel allergy and perfume allergy were the major contact allergies . In the future this cohort of eighth grade school children will be followe d up with regard to the course and development of atopic diseases, hand ecz ema and contact dermatitis.