Background: Respiratory symptoms and asthma in children pose a significant clinical and public health burden. Our aim was to examine exposures to environmental air pollution in relation to asthma and related symptoms in a multi-racial cohort of children.
Methods: We conducted a cross-sectional analysis evaluating the association between reported neighborhood traffic (a proxy for traffic-related air pollution) and asthma among 855 children aged 4 to 8 years old who participated in the Environmental Influences on Child Health Outcomes (ECHO) cohort. The primary outcome, asthma/asthma like symptoms (defined as current and/or past physician diagnosed asthma, past wheezing, or nighttime cough or wheezing in the past 12 months), was assessed by parental report via questionnaire. The relationship between the primary exposure and asthma/asthma like symptoms was examined using logistic regression.
Results: The prevalence of asthma/asthma like symptoms was 23%. Fifteen percent of parents responded “Agree” or “Strongly Agree” to the question, “There is so much traffic along the streets that it makes it difficult or dangerous to walk with my child in my neighborhood” (n=129/855). Children whose parents had affirmed significant neighborhood traffic had a higher odds of having asthma/asthma like symptoms than children without significant neighborhood traffic [adjusted OR=1.78 (95% CI: 1.10, 2.88)] after controlling for child’s race-ethnicity, age, sex, maternal education level, family history of asthma, presence of play equipment in the home environment, public parks in the neighborhood and obesity. Other factors significantly associated with asthma/asthma like symptoms were: non-Hispanic Black and Hispanic race/ethnicity [OR=2.53 (95% CI: 1.43, 4.50)] and [OR=2.25 (95% CI: 1.28, 3.94), respectively, vs. non-Hispanic White referent], play equipment in the home environment or backyard [OR=1.60 (95% CI: 1.09, 2.35)], obese status [OR=2.54 (95% CI: 1.55, 4.17)], male sex [OR=1.53 (1.06, 2.22)] and family history of asthma [OR=3.19 (2.20, 4.64)].
Conclusions: Reported neighborhood traffic, non-Hispanic Black and Hispanic race/ethnicity, male sex, play equipment within the home environment, obesity, and family history of asthma were associated with greater odds for asthma/asthma like symptoms. Further characterization of neighborhood traffic patterns is needed, since many children live near this source of environmental air pollution and significant racial/ethnic disparities exist.