title: The effects of outdoor air pollutants on the costs of pediatric asthma hospitalizations in the United States, 1999 to 2007.
abstract: BACKGROUND
  Acute exposure to outdoor air pollutants has been associated with increased pediatric asthma morbidity. However, the impact of subchronic exposures is largely unknown.
  
  
  OBJECTIVE
  To examine the association between subchronic exposure to 6 outdoor air pollutants (PM2.5, PM10, ozone, nitrogen oxides, sulfur oxides, carbon monoxide) and pediatric asthma hospitalization length of stay, charges, and costs.
  
  
  METHODS
  We linked pediatric asthma hospitalization discharge data from a nationally representative dataset, the 1999-2007 Nationwide Inpatient Sample, with outdoor air pollution data from the Environmental Protection Agency. Hospitals with no air quality data within 10 miles were excluded. Our predictor was the average concentration of 6 pollutants near the hospital during the month of admission. We conducted bivariate analyses using Spearman correlations and multivariable analyses using Poisson regression for length of stay and linear regression for log-transformed charges and costs, controlling for patient demographics, hospital characteristics, and month of admission.
  
  
  RESULTS
  In unadjusted analyses, all 6 pollutants had minimal correlation with the 3 outcomes (ρ<0.1, P<0.001). In multivariable analyses, a 1-unit (μg/m) increase in monthly PM2.5 led to a $123 increase in charges (95% confidence interval $40-249) and a $47 increase in costs (95% confidence interval $15-93). No other pollutants were significant predictors of charges or costs or length of stay.
  
  
  CONCLUSIONS
  Subchronic PM2.5 exposure is associated with increased costs for pediatric asthma hospitalizations. Policy changes to reduce outdoor subchronic pollutant exposure may lead to improved asthma outcomes and substantial savings in healthcare spending.
authors: Departments of Preventive Medicine and Pediatrics, Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, NY 10029, USA. aroy@eriefamilyhealth.org.
authors: Angkana
authors: A
authors: Roy
authors: Perry
authors: P
authors: Sheffield
authors: Kendrew
authors: K
authors: Wong
authors: Leonardo
authors: L
authors: Trasande
mesh_terms: D000293:Adolescent; D000393:Air Pollutants / Q000009:adverse effects* / Q000032:analysis; D001249:Asthma / Q000191:economics* / Q000453:epidemiology* / Q000209:etiology; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D017048:Health Care Costs; D006760:Hospitalization / Q000191:economics*; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D016012:Poisson Distribution; D012044:Regression Analysis
chemical_list: D000393:Air Pollutants