Effect of air pollution and pollen on asthma and pneumonia : using big data of south Korean health-care records

<bold>Background:</bold> Asthma and pneumonia are affected by genetic and environmental predispositions. Sensitization rates of weed and tree pollens are increased in south Korea. The seasonal and regional variations of pollen have also been changed in south Korea with climate change. Exposure to air pollution has also been related to pneumonia and asthma, also. So, we investigated the air pollution and pollen as environmental factors. <bold>Methods:</bold> Asthma and pneumonia of the National Health Insurance Corporation's claim data, pollen data and the Ministry of Environment air environment data (SO2, O3, NO2, PM10, CO) were analyzed, between Jan, 1 2015 and Dec. 31 2019. A total 512,532 patients were included, after regional matching. <bold>Results:</bold> PM10 had highest impact of hospitalization for pneumonia in the metropolitan area, however NO2 had highest impact in rural areas (p <0.001). Emergency room visits for asthma were most influenced by O3 in the metropolitan area, and SO2 in rural areas (p <0.001). When PM10, PM2.5, and pollen were all high, hospitalization for pneumonia were significantly higher after 5 days (p = 0.035). Outpatient visit of asthma was significantly higher in same-day (p=0.007), emergency room visit and hospitalization for asthma were significantly higher after 4 days (p=0.002, P=0.018). <bold>Conclusion:</bold> PM10, NO2, PM2.5, and pollen concentration and was correlated with current hospitalization for asthma and pneumonia and varied by region. The delayed effect of pollen and air pollution on hospitalizations for asthma and pneumonia was 4 and 5 days.