Joint association between ambient air pollutant mixture and pediatric asthma exacerbations

Authors

Jagadeesh Puvvula, University of Nebraska Medical Center
Jill A. Poole, University of Nebraska Medical CenterFollow
Sandra Gonzalez, University of Nebraska-LincolnFollow
Eleanor G. Rogan, University of Nebraska Medical CenterFollow
Yeongjin Gwon, University of Nebraska Medical CenterFollow
Andrew C. Rorie, University of Nebraska Medical CenterFollow
Linda B. Ford, Asthma and Allergy Center
Jesse E. Bell, University of Nebraska Medical CenterFollow

Date of this Version

8-15-2022

Citation

Puvvula et al. Environmental Epidemiology (2022) 6:e225. DOI: 10.1097/EE9.0000000000000225

Comments

Open access

Abstract

Background: Exposure to air pollutants is known to exacerbate asthma, with prior studies focused on associations between single pollutant exposure and asthma exacerbations. As air pollutants often exist as a complex mixture, there is a gap in understanding the association between complex air pollutant mixtures and asthma exacerbations. We evaluated the association between the air pollutant mixture (52 pollutants) and pediatric asthma exacerbations.

Method: This study focused on children (age ≤ 19 years) who lived in Douglas County, Nebraska, during 2016–2019. A seasonal- scale joint association between the outdoor air pollutant mixture adjusting for potential confounders (temperature, precipitation, wind speed, and wind direction) in relation to pediatric asthma exacerbation-related emergency department (ED) visits was evaluated using the generalized weighted quantile sum (qWQS) regression with repeated holdout validation.

Results: We observed associations between air pollutant mixture and pediatric asthma exacerbations during spring (lagged by 5 days), summer (lag 0–5 days), and fall (lag 1–3 days) seasons. The estimate of the joint outdoor air pollutant mixture effect was higher during the summer season (adjusted-β_WQS = 1.11, 95% confidence interval [CI]: 0.66, 1.55), followed by spring (adjusted-β_WQS = 0.40, 95% CI: 0.16, 0.62) and fall (adjusted-β_WQS = 0.20, 95% CI: 0.06, 0.33) seasons. Among the air pollutants, PM_2.5, pollen, and mold contributed higher weight to the air pollutant mixture.

Conclusion: There were associations between outdoor air pollutant mixture and pediatric asthma exacerbations during the spring, summer, and fall seasons. Among the 52 outdoor air pollutant metrics investigated, PM_2.5, pollen (sycamore, grass, cedar), and mold (Helminthosporium, Peronospora, and Erysiphe) contributed the highest weight to the air pollutant mixture.