Air Pollution May Increase Respiratory Viral Infection in Patients With Severe Acute Exacerbation of Chronic Obstructive Pulmonary Disease

초록

RATIONALE: Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is an airway inflammatory event mainly caused by respiratory infections. Air pollution affects the airway epithelial barrier and the immune system, which can influence respiratory infection. However, studies on the relationship between respiratory infections and air pollutants in severe AECOPD have been limited. We investigated the association between air pollution and respiratory pathogen in severe AECOPD. METHODS: This multicenter observational study reviewed patients' electronic medical records with AECOPD in South Korea. We divided patients into four groups according to the comprehensive air-quality index (CAI) used in South Korea. And the identification rates of bacteria and viruses in each group were analyzed. The study protocol was approved by each hospital's Institutional Review Board Committee (Korea University Guro Hospital IRB No. 2019GR0424). RESULTS: We analyzed a total of 735 severe AECOPD patients. Viral pathogens were identified in 270 (36.7 %) of 735 patients. The viral identification rate was different according to the air pollution. (P = 0.012). Especially the virus detection rate was 55.9 % in the group (CAI ‘D’ category) with the highest air pollution and 24.4 % in the group (CAI ‘A’ category) with the lowest air pollution. This pattern was clearly seen in influenza virus A (P = 0.042). When the further analysis was performed with particulate matter (PM), the higher the PM level, the higher the virus detection rate, and the lower the PM level, the lower the virus detection rate. Bacterial pathogens were identified in 194 (26.4 %) of 735 patients. There was no statistically significant difference when analyzed by dividing into four groups according to CAI. Even when examined for each bacterium, statistically significant was not found. CONCLUSIONS: Air pollution may make chronic obstructive pulmonary disease (COPD) patients more susceptible to respiratory viral infections. Furthermore, this phenomenon is conspicuous in influenza virus A. COPD patients need to be more careful about This abstract is funded by: This work was supported by a grant (No. KATRD-S-2019-1) awarded by the Korean Academy of Tuberculosis and Respiratory Diseases.