Stress, Traffic Related Air Pollution and Eczema and Wheeze in the First Year of Life: Project ACCESS

Abstract

ISEE-0832 Background and Objective: While both chronic stress and traffic related air pollution are associated with respiratory health and atopic outcomes in children, studies exploring the joint effect of these exposures are limited. We examined the relationship between violence, conceptualized as a chronic stressor, and black carbon from traffic sources on eczema and wheeze in infancy in the Asthma Coalition on Community, Environment, and Social Stress (ACCESS), an urban prospective birth cohort study in the US. Methods: Mothers reported physician-diagnosed eczema or wheeze in their children during the first year of life and completed the My Exposure to Violence (ETV) scale. Black carbon (BC) exposure levels were estimated using a validated spatio-temporal land use regression model, based on mother’s residence during pregnancy. Rasch modeling was used to create a summary measure of ETV. Associations between predicted BC, ETV and wheeze and eczema were examined adjusting for sociodemographics, birthweight for gestational age, season of birth, in-utero tobacco smoke and postnatal tobacco smoke exposure; infant outcomes were examined in separate regression models. Results: In the sample of 403 children, 15% were diagnosed with eczema and 25% reported wheezing. The mean ± SD predicted annual BC was 0.42 + 0.2 μg/m3. In adjusted analyses, ETV (OR 1.3, 95%CI 1.0, 1.7) and BC per interquartile range (OR 1.3, 95%CI 1.0, 1.8) were associated with wheeze; there was no significant interaction between ETV and BC. In stratified analysis, increased odds of wheeze was seen only among children with both above median ETV and above median BC exposure (OR 2.2, 95%CI 1.1, 4.1) albeit the test for an interaction was not significant. Conclusions: Violence and traffic related BC are independently associated with wheeze in the first year of life but not eczema. These environmental exposures may be operating through pathways other than a predisposition to atopy.