METHODS: We examined socio-demographic predictors and environmental exposures among HW and NHW children aged 4-8 years enrolled in the CHS, 2002-2003.
RESULTS: Eczema prevalence differed by ethnicity: HWs showed lower prevalence (13.8%) compared to NHWs (20.2%) and adjustment for socio-demographic factors did not account for the ethnic difference (odds ratio [OR]=0.79, 95% confidence intervals [CIs]=0.65-0.95). Parental history of allergic disease had a larger effect in HWs than NHWs (P for interaction=0.005). High maternal education level (OR=1.46, 95% CI=1.14-1.87), parental history of allergic disease (OR=2.21, 95% CI=1.78-2.76) and maternal smoking during pregnancy (OR=1.44, 95% CI=1.06-1.95) increased the risk of eczema. Indoor environmental factors (e.g., mold, water damage and humidifier use) increased the risk of eczema in NHWs independent to parental history of allergic disease, but in HWs, increased risks were observed primarily in children without parental history of allergic disease.
CONCLUSIONS: HW children in southern California have a lower prevalence of eczema than NHWs and this ethnic difference is not accounted for by socio-demographic differences. The effects of parental history of allergic disease and indoor environmental exposures on eczema varied by ethnicity suggesting that the etiology of eczema may differ in HWs and NHWs.