Short-Term Effects of Particulate Matter and Its Constituents on Emergency Room Visits for Chronic Obstructive Pulmonary Disease: A Time-Stratified Case-Crossover Study in an Urban Area

Abstract

Background: PM2.5 exposure is associated with pulmonary and airway inflammation, and the health impact might vary by PM2.5 constitutes. This study evaluated the effects of increased short-term exposure to PM2.5 constituents on chronic obstructive pulmonary disease (COPD)-related emergency department (ED) visits and determined the susceptible groups. Methods: This retrospective observational study performed in a medical center from 2007 to 2010, and enrolled non-trauma patients aged >20 years who visited the emergency department (ED) and were diagnosed as COPD. Concentrations of PM2.5, PM10, and the four PM2.5 components, including organic carbon (OC), elemental carbon (EC), nitrate (NO3−), and sulfate (SO42−), were collected by three PM supersites in Kaohsiung City. We used an alternative design of the Poisson time series regression models called a time-stratified and case-crossover design to analyze the data. Results: Per interquartile range (IQR) increment in PM2.5 level on lag 2 were associated with increments of 6.6% (95% confidence interval (CI), 0.5–13.0%) in risk of COPD exacerbation. An IQR increase in elemental carbon (EC) was significantly associated with an increment of 3.0% (95% CI, 0.1–5.9%) in risk of COPD exacerbation on lag 0. Meanwhile, an IQR increase in sulfate, nitrate, and OC levels was not significantly associated with COPD. Patients were more sensitive to the harmful effects of EC on COPD during the warm season (interaction p = 0.019). The risk of COPD exacerbation after exposure to PM2.5 was higher in individuals who are currently smoking, with malignancy, or during cold season, but the differences did not achieve statistical significance. Conclusion: PM2.5 and EC may play an important role in COPD events in Kaohsiung, Taiwan. Patients were more susceptible to the adverse effects of EC on COPD on warm days.

Environmental pollution in North-Eastern Italy and its influence on chronic obstructive pulmonary disease: time series modelling and analysis using visibility graphs

“…Older women had a greater number of hospital admissions when contamination levels increased in autumn. Indeed, hospital admissions were higher for COPD and respiratory illnesses for the older people during the colder periods so that sudden changes in temperature could have a proportional effect on the number of admissions due to an exacerbation of COPD symptoms (Ding et al 2017 ; Bao et al 2020 ; Huang et al 2021 ; Zhu et al 2020 ; Lin et al 2018 ; Santurtún et al 2017 ; Tian et al 2018 ).…”

Impact of a Large Fire and Subsequent Pollution Control Failure at a Coke Works on Acute Asthma Exacerbations in Nearby Adult Residents

“…Finally, this study focused exclusively on asthma outcomes. Prior studies have documented an impact of short-term OAP on other respiratory outcomes, including COPD-related ED visits [ 68 , 69 ]. It is possible that COPD and other respiratory related ED visits were also increased after the fire; however, examination of this outcome was beyond the scope of this study.…”

Ambient Air Pollution and Risk for Stroke Hospitalization: Impact on Susceptible Groups

“…A time-stratified case-crossover study design was used to calculate the health effects of short-term exposure to air pollutants. The study design has been described previously [ 5 , 17 ]. In brief, the case-crossover study design is an alternative type of case-control study in which within-subject comparisons are performed using “case” and “control” periods [ 18 , 19 ].…”