Korean J Occup Environ Med.  2000 Jun;12(2):249-257.

A case-crossover study between air pollution and hospital emergency room visits by asthma attack

• Im HJ
• Lee SY
• Yun KJ
• Ju YS
• Kang DH
• Cho SH

Abstract

OBJECTIVES
This study, using case-crossover design, search a relationship between changing levels of air pollutants and asthma attack in asthma patients.
METHODS
We searched the daily total number of asthmatic patients at hospital' s emergency room in Seoul, Korea by investigating total 49 general hospitals emergency room records. Otherwise, We investigated medical records of asthmatic patients at one of the 49 hospitals we have searched. We investigated addresses that they are living, diagnosis, smoking history, whether respiratory infection or not, medications. We analyzed the data by 1:m conditional logistic regression used when matched case-control study is analyzed. Control periods were chosen by bidirectional paired matching technique 7, 14 days before and after case periods.
RESULTS
the relative risk of asthmatic attack by 100 ppm ozone increase between June and September were 1.348(95 % CI = 1.010~1.619). Between November and February, the relative risk by 100 /m TSP increase, 100ppb sulfur dioxide and nitrogen dioxide were respectively 1.278(1.010~1.619), 1.237(1.019~1.502), 1.285(1.006~1.640). In stratified analysis, the relative risk were significant when the asthmatic patients were children aged 15 years or below, when there were respiratory infection, and when the patients took medications irregularly
CONCLUSIONS
There was statistically significant association between ambient levels of air pollutants and asthmatic attack. So, we have to exert our efforts to minimize the air pollution effectively, to protect public health from air pollution.

Keyword

air pollution; asthma attack; case-crossover design; air pollutants

MeSH Terms

Air Pollutants
Air Pollution*
Asthma*
Case-Control Studies
Child
Diagnosis
Emergencies*
Emergency Service, Hospital*
Hospitals, General
Humans
Korea
Logistic Models
Medical Records
Nitrogen Dioxide
Ozone
Public Health
Seoul
Smoke
Smoking
Sulfur Dioxide
Air Pollutants
Nitrogen Dioxide
Ozone
Smoke
Sulfur Dioxide