Exposure to Pet or High-Level Outdoor PM2.5 in the First Year of Life and Risk of Atopic Dermatitis at 6 to 7 Years of Age

Abstract

Objective:The prevalence of non-infectious diseases, especially allergic diseases, have been increased in Korea. The aim of this study is to find out the association between exposure to pet or high-level outdoor PM2.5 in the first year of life and atopic dermatitis at 6 to 7 years of age in Korean children.Design and subjects:Based on the International Study of Asthma and Allergies in Childhood Study (ISAAC) in Korea (2010-2011), we analysed 848 1st grade elementary school students who had available data on ISAAC questionnaires in Seoul. To rule out genetic factors, we excluded children whose parents with atopic dermatitis from our studies. Atopic dermatitis was defined in a students who had self-reported symptoms or had treatment for atopic dermatitis within the last 12 months or diagnosis by physician in lifetime. Outdoor PM 2.5 concentration was obtained through the actual measurement. The association between exposure to pet or high-level PM2.5 during the first year of birth and atopic dermatitis was analyzed by using Multiple logistic regression. We used sex, age, breast-fed level as covariates in our model. Statistical analyses were performed using R .Results:Among 848 participants, 349(49.3%) were boys and 255 (30.1%) children turned out to be positive for atopic dermatitis. Forty one children (5.9%) ware exposed to pet within the first year of life and 24-hour mean concentration of outdoor PM2.5 within the first year of life was 32.4µg/m3 . In multiple logistic regression model, we found a significant association between pet exposure and high-level exposed to PM2.5 and atopic dermatitis after adjusting for covariates (the crude odds ratio (OR) =2.22, 95%CI:0.96 – 5.17, adjusted OR =2.47 95%CI: 1.01 – 6.08).Conclusion:We found a significant association between raising pets and exposed to high-level PM2.5 and atopic dermatitis in Korean children. Further longitudinal epidemiologic study will be needed to get more strong scientific evidence of this association.