Susceptibility to air pollution effects on mortality in Seoul, Korea: A case-crossover analysis of individual-level effect modifiers

Ji Young Son, Jong Tae Lee, Ho Kim, Okhee Yi, Michelle L. Bell

Research output: Contribution to journalArticlepeer-review

35 Citations (Scopus)


Air pollution's mortality effects may differ by subpopulation; however, few studies have investigated this issue in Asia. We investigated susceptibility to air pollutants on total, cardiovascular, and respiratory mortality in Seoul, Korea for the period 2000-2007. We applied time-stratified case-crossover analysis, which allows direct modeling of interaction terms, to estimate susceptibility based on sex, age, education, marital status, and occupation. An interquartile range increase in pollution was associated with odds ratios of 0.94 (95% confidence interval, 0.25-1.62), 2.27 (1.03-3.53), 1.94 (0.80-3.09), and 2.21 (1.00-3.43) for total mortality and 1.95 (0.64-3.27), 4.82 (2.18-7.54), 3.64 (1.46-5.87), and 4.32 (1.77-6.92) for cardiovascular mortality for PM 10, nitrogen dioxide (NO 2), sulfur dioxide (SO 2), and carbon monoxide (CO), respectively. Ozone effect estimates were positive, but not statistically significant. Results indicate that some populations are more susceptible than others. For total or cardiovascular mortality, associations were higher for males, those 65-74 years, and those with no education or manual occupation for some pollutants. For example, the odds ratio for SO 2 and cardiovascular mortality was 1.19 (1.03-1.37) times higher for those with manual occupations than professional occupations. Our findings provide evidence that some populations are more susceptible to the effects of air pollution than others, which has implications for public policy and risk assessment for susceptible subpopulations .

Original languageEnglish
Pages (from-to)227-234
Number of pages8
JournalJournal of Exposure Science and Environmental Epidemiology
Issue number3
Publication statusPublished - 2012 May

Bibliographical note

Funding Information:
This work was supported by the US National Institute of Environmental Health Sciences (R01 01ES015028).


  • air pollution
  • effect modifiers
  • mortality
  • susceptible subpopulations
  • time-stratified case-crossover analysis

ASJC Scopus subject areas

  • Epidemiology
  • Toxicology
  • Pollution
  • Public Health, Environmental and Occupational Health


Dive into the research topics of 'Susceptibility to air pollution effects on mortality in Seoul, Korea: A case-crossover analysis of individual-level effect modifiers'. Together they form a unique fingerprint.

Cite this