Abstract
BACKGROUND: There is limited knowledge regarding prevalence and characteristics of atopic dermatitis (AD) among young adults in the general population. OBJECTIVES: To study AD among young adults in a Swedish population-based birth cohort, with a particular focus on prevalence, sex differences including risk for AD at different ages, disease course and characteristics of AD at 24 years. METHODS: The BAMSE cohort includes 4089 individuals who have been followed regularly from birth to age 24 years regarding AD and atopic diseases. For this study 3055 individuals who answered questions regarding AD at the 24-year follow-up were included. All were invited to a clinical examination including skin examination, evaluation by William's criteria and collection of blood for analysis of specific IgE, and 2264 individuals chose to participate. RESULTS: At 24 years, the 12-month prevalence of AD was 17.8% and more females than males had AD (20.5% vs. 14.8%), P < 0.0001. The point prevalence of ongoing AD at clinical examination was 8.0%. AD severity as assessed by Patient-Oriented Eczema Measure (POEM) did not differ between sexes. The proportion of adult onset of AD was 16.9% (92 of 543), females 17.3% vs. males 16.4%. More females than males with AD at 24 years reported disturbed sleep due to itch (26.1% vs. 15.5%, P < 0.003). IgE sensitization was less common among females with AD than males with AD (61.3% vs. 79.6%, P < 0.0001). In addition, male sex (female sex being the reference) was associated with increased odds for AD the first year of life (OR: 1.31, 95% CI; 1.10-1.56), and decreased odds of AD in adolescence and young adulthood (OR: 0.66, 95% CI; 0.55-0.80). CONCLUSIONS: Atopic dermatitis is a common disease among young adults, and even though more females than males have AD at 24 years, adult onset of AD seems to be equally prevalent among both sexes in young adulthood.