American Journal of Epidemiology Advance Access originally published online on February 17, 2007
American Journal of Epidemiology 2007 165(8):927-935; doi:10.1093/aje/kwk088
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ORIGINAL CONTRIBUTIONS |
Air Pollution Sources and Childhood Asthma Attacks in Cataño, Puerto Rico
1 Office of Surveillance and Biometrics, Center for Devices and Radiological Health, Food and Drug Administration, US Department of Health and Human Services, Rockville, MD
2 Department of Biostatistics, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD
3 Center for Imaging Science, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD
4 Department of Psychiatry, School of Medicine, Johns Hopkins University, Baltimore, MD
5 Division of Environmental and Occupational Health, School of Medicine, Johns Hopkins University, Baltimore, MD
6 Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD
7 District of Columbia Cancer Registry, District of Columbia Health Department, Washington, DC
Correspondence to Dr. Nilsa I. Loyo-Berríos, Center for Devices and Radiological Health, Food and Drug Administration, US Department of Health and Human Services, 1350 Piccard Drive, HFZ-541, Rockville, MD 20850 (nilsa.loyo-berrrios{at}fda.hhs.gov).
Received for publication May 9, 2006. Accepted for publication October 9, 2006.
Asthma prevalence in the Cataño Air Basin of Puerto Rico is 27% for children aged 13–14 years and 45% for children aged 5–6 years. There is concern that these rates are related to air pollution. The authors conducted a nested case-control study to evaluate whether proximity to air pollution point sources was associated with increased risk of asthma attacks. For 1997–2001, 1,382 asthma-related medical visits (International Classification of Diseases, Ninth Revision, codes 493 and 493.9) in children under 17 were identified through health insurance claims. Controls were children with no asthma attacks who were randomly selected from enrollees in two health insurance companies by incidence density sampling (1:5) and matched to cases on gender, age, insurance company, and event date. The distance from a point source to the subject's residence area represented a surrogate exposure measurement. Odds ratios for a 1-km decrease in distance were obtained by conditional logistic regression. Risk of asthma attack was associated with residing near a grain mill (odds ratio (OR) = 1.35), petroleum refinery (OR = 1.44), asphalt plant (OR = 1.23), or power plant (OR = 1.28) (all p's < 0.05). Residence near major air emissions sources (>100 tons/year) increased asthma attack risk by 108% (p < 0.05). These results showed that proximity to some air pollution sources is associated with increased risks of asthma attacks.
air pollution; asthma; child
Abbreviations: CI, confidence interval; OR, odds ratio