J Prev Med Public Health.  2016 Sep;49(5):329-341. 10.3961/jpmph.16.038.

Short-term Effects of Ambient Air Pollution on Emergency Department Visits for Asthma: An Assessment of Effect Modification by Prior Allergic Disease History

• Noh J
• Sohn J
• Cho J
• Cho SK
• Choi YJ
• Kim C
• Shin DC

• KMID: 2356076
• DOI: http://doi.org/10.3961/jpmph.16.038

Abstract

OBJECTIVES
The goal of this study was to investigate the short-term effect of ambient air pollution on emergency department (ED) visits in Seoul for asthma according to patients' prior history of allergic diseases.
METHODS
Data on ED visits from 2005 to 2009 were obtained from the Health Insurance Review and Assessment Service. To evaluate the risk of ED visits for asthma related to ambient air pollutants (carbon monoxide [CO], nitrogen dioxide [NO₂], ozone [O₃], sulfur dioxide [SO₂], and particulate matter with an aerodynamic diameter <10 μm [PM₁₀]), a generalized additive model with a Poisson distribution was used; a single-lag model and a cumulative-effect model (average concentration over the previous 1-7 days) were also explored. The percent increase and 95% confidence interval (CI) were calculated for each interquartile range (IQR) increment in the concentration of each air pollutant. Subgroup analyses were done by age, gender, the presence of allergic disease, and season.
RESULTS
A total of 33 751 asthma attack cases were observed during the study period. The strongest association was a 9.6% increase (95% CI, 6.9% to 12.3%) in the risk of ED visits for asthma per IQR increase in O₃ concentration. IQR changes in NO₂ and PM₁₀ concentrations were also significantly associated with ED visits in the cumulative lag 7 model. Among patients with a prior history of allergic rhinitis or atopic dermatitis, the risk of ED visits for asthma per IQR increase in PM₁₀ concentration was higher (3.9%; 95% CI, 1.2% to 6.7%) than in patients with no such history.
CONCLUSIONS
Ambient air pollutants were positively associated with ED visits for asthma, especially among subjects with a prior history of allergic rhinitis or atopic dermatitis.

Keyword

Air pollution; Asthma; Emergencies; Time series analysis; Effect modifier; Korea

MeSH Terms

Air Pollutants
Air Pollution*
Asthma*
Dermatitis, Atopic
Emergencies*
Emergency Service, Hospital*
Humans
Insurance, Health
Korea
Nitrogen Dioxide
Ozone
Particulate Matter
Rhinitis, Allergic
Seasons
Seoul
Sulfur Dioxide
Air Pollutants
Nitrogen Dioxide
Ozone
Particulate Matter
Sulfur Dioxide