Yet Again, Air Pollution Impacts Lung Health

Details

• Personal Author:
  Goss CH ; Sack CS
• Description:
  In this issue of the AnnalsATS, Yitshak-Sade and colleagues (pp. 1796-1802) present a case-cross-over study from southern Israel that adds significantly to this literature. In contrast to other studies, the authors have selected an area exposed to high levels of pollutants with significant contributions from nonanthropogenic sources-mainly dust storms composed of crustal matter. In addition, they have selected a unique population comprised of 80% urban Jews and 20% Bedouin-Arabs. By leveraging the case-cross-over study design, they can study this diverse population, controlling for many potential confounders and investigating several different periods of exposure. ... One of the major strengths of this study was the case-cross-over design that allowed the authors to control for a wide range of variables, such as sex, age, and socioeconomic factors. However, it is important to recognize the limitations of this study design. First, it does not account for time-varying characteristics that may be closely linked to bronchiolitis. For example, household crowding and environmental tobacco smoke exposure may be significantly different in case versus control periods. Because these variables should not be strongly associated with ambient air pollutant exposures, it is likely that these unmeasured variables may attenuate results, and bias toward the null. Second, it is important to accurately characterize the temporal onset of the outcome for this analysis. Nearly 20% of the population had been prescribed steroids 10 days before their hospital admission, implying that many participants were symptomatic before their admission. By classifying the case period as 0-7 days before hospitalization, the authors may miss the critical time window in many study participants. This distinction effects the interpretation of whether exposure to air pollution enhances susceptibility to infection or, rather, worsens disease severity. In addition to these considerations, this is an observational study with errors in exposure measurement, outcome misclassification, and an inability to infer causation. Cases of bronchiolitis were ascertained retrospectively from International Classification of Diseases, Ninth Revision codes rather than clinical diagnoses, and may include pneumonia, croup, or other respiratory infections. Although the authors used sophisticated models of air pollutants, exact home addresses were not available for the majority of study subjects. Furthermore, assigning exposure based on residence does not accurately reflect pollutant exposure in the participants' microenvironment. Despite these limitations, the conclusions from this study are compelling and show a consistent association between acute exposure to pollution and the odds of hospitalization for bronchiolitis. These findings add significantly to prior literature, and highlight the role of air pollution in respiratory tract infections. More studies are needed to determine susceptible populations and further our understanding of the complex interaction that mediates these effects. [Description provided by NIOSH]
• Subjects:
  Air Pollutants, Occupational Air Pollution Lung Diseases Occupational Health Particulate Matter Respiratory System Respiratory Tract Diseases Safety
• Keywords:
  Air Pollutants Air Pollution Lung Disease Particulates Respiratory Diseases
• ISSN:
  2329-6933
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 10 ; Washington
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  14
• Issue:
  12
• NIOSHTIC Number:
  nn:20063801
• Citation:
  Ann Am Thorac Soc 2017 Dec; 14(12):1761-1762
• Contact Point Address:
  Cora S. Sack, M.D., Occupational Medicine, Pulmonary and Critical Care Medicine, University of Washington Medical Center, Campus Box 356522, 1959 N.E. Pacific, Seattle, WA 98195
• Email:
  cssack@u.washington.edu
• Federal Fiscal Year:
  2018
• Performing Organization:
  University of Washington
• Peer Reviewed:
  False
• Start Date:
  20050701
• Source Full Name:
  Annals of the American Thoracic Society
• End Date:
  20250630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:62d1f802f4504aa247bb00da3e74319338d92bc3ce5afc975b835a0fde63c7e1e0a62b3491d24cbae37e83e4ab0cbd3b18cb9e87bcc13defc227120951786de2
• Download URL:
  https://stacks.cdc.gov/view/cdc/222354/cdc_222354_DS1.pdf
• File Type:
  [PDF - 422.52 KB ]