Residential Risk Factors for Atopic Dermatitis in 3- to 6-Year Old Children: A Cross-Sectional Study in Shanghai, China

BACKGROUND Atopic dermatitis (AD) is common among pre-school children in Shanghai. This study aimed to identify the risk factors for childhood AD from the perspectives of home environment, demographics and parents-grandparents' atopic disease. METHODS A cross-sectional study was conducted in Shanghai in April-June, 2010. Preschool children's parents or guardians were invited to participate a questionnaire survey in six districts (two urban and four suburban/rural) and 6624 children were finally recruited (51.3% boys). AD diagnosis was based on the U.K. Working Party's (UKWP) criteria. Adjusted odds ratios (AOR) with 95% confidence intervals (95% CI) were calculated by multiple logistic regression. RESULTS A total of 8.5% of children ever had AD. Around 10.2% of the mothers had lived in newly renovated/decorated homes (NRDH) during the prenatal period (one year before or during pregnancy) and 9.5% got new home furniture (NHF) during the same period. AD was more common in children when mothers had lived in NRDH homes during the prenatal period (AOR = 1.41; 95% CI 1.03-1.93), the current home had indoor mold (2.00, 1.48-2.70), parents-grandparents' had atopic diseases (3.85, 3.05-4.87), the children had food allergy (3.40, 2.63-4.40) or children lived in urban area (1.52, 1.18-1.96). Associations between AD and NRDH, NHF and indoor molds were only significant in children without parents-grandparents' atopic diseases. There was an interaction effect between parents-grandparents' atopic diseases and NRDH (p < 0.05). CONCLUSIONS Home renovation/ redecoration, new furniture and indoor mold, urban residency, heredity disposition and food allergy can be risk factors for childhood AD in Shanghai.