Is Adult Atopic Eczema More Common Than We Think? - A Population-based Study in Danish Adults

Atopic eczema (AE) is a common chronic skin disease which primarily affects children but may extend into adulthood. Mutations of filaggrin and abnormalities of stratum corneum ceramides are currently considered to be major aetiological factors of AE (1). Epidemiological studies suggest a marked increase in the prevalence of AE over the last decades, but recent studies in children suggest that the prevalence in countries with the highest prevalence has reached a steady level (2, 3). Worldwide prevalence rates for children range from 0.2-24.6% (2, 4). Much less is known about adult AE. Based on the current understanding of the disease as a consequence of a genetically determined barrier defect, a cohort effect may be hypothesised, which would lead to adult AE prevalence rising. Different screening methods have suggested the adult one-year prevalence estimates range between 0.3-11.5% (5-7). Questionnaire studies present an appealing method for the collection of prevalence data in large population samples. The UK Working Party's Diagnostic Criteria for Atopic Dermatitis (now UK diagnostic criteria) (8) are used in many studies; however additional validation in the very young and in adults may be needed. For adults former use of the UK diagnostic criteria (questionnaire) showed an overall one-year prevalence of 2.9% in Japan (9). Additional population-based studies of adult AE therefore appear warranted, as such studies are rare and the results show considerable variation. The aim of this study was to investigate the prevalence of AE in a Danish adult population using the UK diagnostic criteria.