Short-Term Air Pollution Exposure and Risk of Acute Exacerbation of Chronic Obstructive Pulmonary Disease in Korea: A National Time-Stratified Case-Crossover Study

Yun Jung Jung,Eun Jin Kim,Jung Yeon Heo,Dae Jung Kim,Kyoung Hwa Ha,Young Hwa Choi

doi:10.3390/ijerph19052823

Abstract

We investigated the association between short-term exposure to air pollution and the risk of acute exacerbation of chronic obstructive pulmonary disease (AE-COPD) in seven metropolitan cities in Korea. We used national health insurance claims data to identify AE-COPD cases in 2015. We estimated short-term exposure to particulate matter (PM) with a diameter of ≤2.5 μm (PM2.5), PM with diameters of ≤10 μm (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3) obtained from the Ministry of Environment. We conducted a time-stratified, case-crossover study to evaluate the effect of short-term exposure to air pollution on hospital visits for AE-COPD, using a conditional logistic regression model. The risk of hospital visits for AE-COPD was significantly associated with interquartile range increases in PM10 in a cumulative lag model (lag 0–2, 0.35%, 95% confidence interval (CI) 0.06–0.65%; lag 0–3, 0.39%, 95% CI 0.01–0.77%). The associations were higher among patients who were men, aged 40–64 years, with low household income, and with a history of asthma. However, other air pollutants were not significantly associated with the risk of hospital visits for AE-COPD. Short-term exposure to air pollution, especially PM10, increases the risk of hospital visits for AE-COPD.

Highlights

Among patients with Acute exacerbation of Chronic obstructive pulmonary disease (COPD) (AE-COPD) in 2015, 74.6% were men, 71.3% were aged ≥65 years, 89.5% had a prior history of asthma, and 67.7% had at least one AE-COPD event in the previous year (Table 1)
PM with diameters of ≤10 μm (PM10) levels were associated with an increased risk of hospital visits for AE-COPD in lag 0–2 (0.35%; 95% confidence interval (CI) 0.06–0.65%) and lag 0–3 (0.39%; 95% CI 0.01–0.77%)
An increase in PM10 levels was associated with the risk of AE-COPD during cumulative lag 0–2 and lag 0–3 models

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Chronic obstructive pulmonary disease (COPD) is a progressive inflammatory disease characterized by airway limitation that is not completely reversible [1]. World Health Organization (WHO), COPD is the third leading cause of death worldwide [2]. Acute exacerbation of COPD (AE-COPD) is defined as acute worsening of respiratory symptoms, such as dyspnea, cough, and sputum production, beyond normal day-to-day variations, resulting in changes in regular medication [3]. AE-COPD has a significant impact on a patient’s quality of life and can accelerate the decline in lung function [4]

Methods

Discussion

Conclusion