Exposure to Gene-Environment Interactions before 1 Year of Age May Favor the Development of Atopic Dermatitis

Abstract

Background: The aims of this study were to determine (1) the prevalence of atopic dermatitis (AD) in Seoul, Korea, and (2) the influence of environmental and genetic factors on disease risk. Methods: A questionnaire survey was conducted in 5,036 primary school children and 4,607 middle school children in 2008. For each child, a modified version of the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire and a questionnaire assessing exposure to environmental variables were completed. Results: In primary school children, the lifetime prevalence of itchy eczema was 24.3%, the 12-month prevalence of itchy flexural eczema was 18.0%, the lifetime prevalence of AD diagnosis was 31.3%, and the 12-month prevalence of AD treatment was 14.5%. In middle school children, the corresponding rates were 16.0, 10.8, 22.1, and 8.3%, respectively. These rates are significantly higher than those reported in similar studies conducted in 1995 and 2000. In both primary and middle school children, a parental history of allergic disease and a history of having moved into a newly built house before 1 year of age were independently associated with a risk for current AD. For current AD, the prevalence odds ratio was higher in the subgroup with both a genetic and a specific environmental risk factor than in the subgroup with no risk factor or subgroups with only one risk factor. Conclusions: The prevalence of AD in primary and middle school children in Seoul has increased. Its development may be influenced by gene-environment interactions, particularly before 1 year of age.

Gene-environment interaction between Toll-like receptor 4 and mold exposure in the development of atopic dermatitis in preschool children

“…4,8,16,30) In the present study, parental history of AD was the only significant familial risk factor for AD in preschool children; parental histories of other allergic diseases such as asthma and allergic rhinitis were not significant.…”

“…16) Previously we reported early life exposure to mold was important risk factor for the development of AD especially in susceptible children. 4) Some studies have shown that markers of indoor dampness, such as visible mold and water damage, were associated with increased risk of AD in childhood, 17,18) but this association was not found in all studies. 6) The relative importance of mold exposure for the development of AD in preschool children remains unexplored.…”

“…Association between mold exposure and the development of AD was identified in our previous study. 4) So the questionnaires related to mold exposure are subclassified into 5 categories (dampness stain, dampness damage, visible mold, mold odor and house repair due to mold) in this …”

“…1) The prevalence of AD is increasing in developed countries, including Korea, probably due to changes in lifestyle and the environment. [2][3][4][5] The etiology of AD is thought to be associated with diverse factors including personal, genetic and environmental factors. The rapid increase in the prevalence of AD over the last 30 to 40 years suggests that environmental factors rather than genetic effects are responsible for this increased prevalence, although interactions between genetic and environmental factors may also be important.…”

“…[6][7][8] Recent clinical research has therefore focused on identifying gene-environment interactions that contribute to the development of allergic diseases including AD. 4,[8][9][10][11][12][13] Household moisture and mold are associated with adverse health effects in children, 14,15) and mold is considered as a key indoor environmental exposure. 16) Previously we reported early life exposure to mold was important risk factor for the development of AD especially in susceptible children.…”