AUTHOR=Chen Te-Yu , Chen Szu-Chia , Wang Chih-Wen , Tu Hung-Pin , Chen Pei-Shih , Hu Stephen Chu-Sung , Li Chiu-Hui , Wu Da-Wei , Hung Chih-Hsing , Kuo Chao-Hung 

TITLE=The impact of the synergistic effect of SO2 and PM2.5/PM10 on obstructive lung disease in subtropical Taiwan

JOURNAL=Frontiers in Public Health

VOLUME=11

YEAR=2023

URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2023.1229820

DOI=10.3389/fpubh.2023.1229820

ISSN=2296-2565

ABSTRACT=<sec id="sec1"><title>Background</title><p>Chronic Obstructive lung diseases (COPD) are complex conditions influenced by various environmental, lifestyle<strike>,</strike> and genetic factors. Ambient air pollution has been identified as a potential risk factor, causing 4.2 million deaths worldwide in 2016, accounting for 25% of all COPD-related deaths and 26% of all respiratory infection-related deaths. This study aims to evaluate the associations among chronic lung diseases, air pollution, and meteorological factors.</p></sec><sec id="sec2"><title>Methods</title><p>This cross-sectional study obtained data from the Taiwan Biobank and Taiwan Air Quality Monitoring Database. We defined obstructive lung disease as patients with FEV1/FVC &lt; 70%. Descriptive analysis between spirometry groups was performed using one-way ANOVA and the chi-square or Fisher’s exact test. A generalized additive model (GAM) was used to evaluate the relationship between SO<sub>2</sub> and PM<sub>2.5</sub>/PM<sub>10</sub> through equations and splines fitting.</p></sec><sec id="sec3"><title>Results</title><p>A total of 2,635 participants were enrolled. Regarding environmental factors, higher temperature, higher relative humidity, and lower rainfall were risk factors for obstructive lung disease. SO<sub>2</sub> was positively correlated with PM<sub>10</sub> and PM<sub>2.5</sub>, with correlation coefficients of 0.53 (<italic>p</italic> &lt; 0.0001) and 0.52 (p &lt; 0.0001), respectively. Additionally, SO<sub>2</sub> modified the relative risk of obstructive impairment for both PM<sub>10</sub> [<italic>β</italic> coefficient (<italic>β</italic>) = 0.01, <italic>p</italic> = 0.0052] and PM<sub>2.5</sub> (<italic>β</italic> = 0.01, <italic>p</italic> = 0.0155). Further analysis per standard deviation (per SD) increase revealed that SO<sub>2</sub> also modified the relationship for both PM<sub>10</sub> (<italic>β</italic> = 0.11, <italic>p</italic> = 0.0052) and PM<sub>2.5</sub> (<italic>β</italic> = 0.09, <italic>p</italic> = 0.0155). Our GAM analysis showed a quadratic pattern for SO<sub>2</sub> (per SD) and PM<sub>10</sub> (per SD) in model 1, and a quadratic pattern for SO<sub>2</sub> (per SD) in model 2. Moreover, our findings confirmed synergistic effects among temperature, SO<sub>2</sub> and PM<sub>2.5</sub>/PM<sub>10</sub>, as demonstrated by the significant associations of bivariate (SO<sub>2</sub> vs. PM<sub>10</sub>, SO<sub>2</sub> vs. PM<sub>2.5</sub>) thin-plate smoothing splines in models 1 and 2 with obstructive impairment (<italic>p</italic> &lt; 0.0001).</p></sec><sec id="sec4"><title>Conclusion</title><p>Our study showed high temperature, humidity, and low rainfall increased the risk of obstructive lung disease. Synergistic effects were observed among temperature, SO<sub>2</sub>, and PM<sub>2.5</sub>/PM<sub>10</sub>. The impact of air pollutants on obstructive lung disease should consider these interactions.</p></sec>