Dataset Information

Indoor endotoxin, proximity to a major roadway, and severe asthma exacerbations among children in Puerto Rico.

ABSTRACT:

Background

Few studies have examined concurrent exposure to household endotoxin and traffic-related air pollution in relation to childhood asthma, yet both factors are associated with asthma outcomes.

Objective

To examine whether proximity to a major roadway (a traffic-related air pollution proxy) modifies the estimated effects of indoor endotoxin on asthma outcomes in children.

Methods

Cross-sectional study of 200 children with asthma (ages, 6-14 years) living in Puerto Rico. Residential distance to a major roadway was calculated as the distance from the participant's residential US census block centroid to the nearest major road. The outcomes of interest were severe asthma exacerbations, missed school days for asthma, atopy, lung function, and bronchodilator response (BDR). Logistic, linear, or negative binomial regression was used for the multivariable analysis.

Results

In the multivariable analysis, there was an interaction between indoor endotoxin and residential distance to a roadway on severe asthma exacerbations (P = .02) and BDR (P = .07). In an analysis stratified by distance to a roadway, each log₁₀-unit increase in endotoxin was associated with 4.21 times increased odds of severe asthma exacerbations among children living within 499 m (the lower 3 quartiles of residential distance) to a road (95% confidence interval, 1.5-12.0). Among subjects living further than 499 m away from a roadway, each log₁₀-unit increase in endotoxin was associated with reduced odds of severe asthma exacerbations (odds ratio, 0.03; 95% confidence interval, 0.001-0.67). Similar but less substantial findings were observed for BDR.

Conclusion

Our findings suggest that residential proximity to a major road modifies the estimated effect of endotoxin on severe asthma exacerbations in children.

SUBMITTER: Rosser F

PROVIDER: S-EPMC7680389 | biostudies-literature |

REPOSITORIES: biostudies-literature

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