Associations between obesity and asthma in a low-income, urban, minority population

Community-based studies of obesity, asthma, biomarkers of oxidative stress, and adipokines among low-income, urban, minority populations are lacking. Oxidative stress, perhaps modulated by adipokines, may increase airway inflammation in obese individuals.

To characterize associations between obesity and asthma in a low-income, urban, minority community and evaluate adipokines, biomarkers of inflammation, and oxidant-antioxidant balance in association with asthma and obesity.

A door-to-door evaluation of asthma and obesity prevalence was performed in a low-income housing development. Nonsmoking adults and children underwent additional evaluation, including allergy skin testing, and measures of serum adipokines, and indicators of oxidative stress in blood and exhaled breath.

The prevalences of current asthma and a body mass index in the 85th percentile or higher were 15.8% and 35.3%, respectively, among 350 nonsmokers older than 4 years. Asthma and obesity were not associated with one another (odds ratio, 1.0; 95% confidence interval, 0.55-1.84). Among 116 nonsmoking participants who underwent biomarker evaluation, obesity was not associated with exhaled nitric oxide. In multivariate logistic models that adjusted for age category, sex, and a body mass index in 85th percentile or higher, leptin concentrations in the highest quartile were associated with asthma (odds ratio, 8.34; 95% confidence interval, 1.29-50.2) but not with atopy. Adiponectin was associated with total antioxidant capacity in exhaled breath.

Asthma and obesity, although both common in a low-income, minority community, were not associated with one another. Nevertheless, adipokines were associated with asthma status and with markers of oxidative stress in the lungs, providing some support for an adipokine-inflammatory mechanistic link between the two conditions.