ABSTRACT
Epidemiology focuses on disease risk factors and evaluating the interventions that can prevent and treat the disease. All of these metrics are important in assessing atopic dermatitis (AD). Different disease classification schemes have been proposed and used in the AD epidemiology literature. Although atopy can occur in elderly people, the lifetime prevalence of AD is considerably lower in them compared with prevalence among younger adults, which, in turn, is considerably lower than that seen in children. Population-based longitudinal studies in Japan have illustrated an increased incidence and prevalence. Dietary allergens probably have some role in allergic sensitization, especially in early life, and this might contribute to the severity of AD. The interplay of genetics and multiple environment factors are probably crucial, and the full complexity of AD and its variants will hopefully be revealed with further research.
