Study On Correlation Of Air Pollution And Meteorological Factors And Emergency Room Visits For Respiratory Diseases In Guangzhou

Objective:1.To analyse the impact of air pollution on the number of emergency visits for total respiratory diseases,acute upper respiratory tract infections,bronchitis,chronic obstructive pulmonary disease（COPD）and asthma,as well as its lagged and cumulative effects,by collecting data on emergency visits for respiratory diseases in Guangzhou from 2013 to 2015,as well as data on air pollution and meteorological factors during the same period.2.To analyse the effects of air pollution on total respiratory diseases under different temperature and relative humidity conditions,with a view to providing a basis for the development of targeted air pollution emergency measures and climate change mitigation response strategies.Methods:1.Using Microsoft Excel 2016 to collect and collate data on emergency visits for respiratory diseases,air pollution and meteorological data in Guangzhou between 2013 and 2015,and summarize the disease data by gender and age,and use R 3.6.3 to perform descriptive analysis and Spearman correlation test on the data.2.In R 3.6.3 to develop a generalized additive model to analyse the effect of air pollution on the incidence of respiratory identical diseases and its lag and cumulative effects.3.To analyse the effect of air pollution on the number of emergency visits for respiratory diseases under different climatic conditions,stratified by temperature and relative humidity,and stratified by gender and age.Results:1.From 2013 to 2015,the average daily concentrations of SO₂,NO₂,O₃,PM₁0 and PM₂.5 in Guangzhou were 16.20μg/m3,49.80μg/m3,83.30μg/m3,66.10μg/m3 and 45.40μg/m3 respectively.During the study period,there were a total of 1,240,615 emergency visits for respiratory diseases,including 602,427 visits for acute upper respiratory tract infections,137,882 visits for bronchitis,11,919 visits for COPD,and 14,755 visits for asthma.2.Between SO₂,NO₂,O₃,PM₁0 and PM₂.5,there was a significant positive correlation between all pollutants,except for NO₂ and O₃,for which there was no correlation.There were significant negative correlations between temperature and NO₂,PM₁0 and PM₂.5,and positive correlations between O₃.There was a negative correlation between relative humidity and SO₂,O₃,PM₁0 and PM₂.5.3.After adjusting for long-term trends in time,temperature,relative humidity and day-of-week effects,each 10μg/m3 increase in daily mean concentrations of SO₂,NO₂,O₃,PM₁0 and PM₂.5 was associated with an increase in total respiratory diseases of 0.75%（95%CI:0.62%-0.88%）,1.77%（95%CI:1.65%-1.89%）,0.36%（95%CI:0.30%-0.42%）,0.92%（95%CI:0.85%-1.00%）and 1.10%（95%CI:1.00%-1.21%）respectively;and an increase in acute upper respiratory tract infection emergencies of 1.22%（95%CI:1.04%-1.40%）,2.05%（95%CI:1.87%-2.22%）,0.41%（95%CI:0.33%-0.49%）,1.15%（95%CI:1.04%-1.26%）and 1.36%（95%CI:1.21%-1.51%）respectively;and an increase in bronchitis emergencies of 0.69%（95%CI:0.32%-1.07%）,1.38%（95%CI:1.03%-1.73%）,0.64%（95%CI:0.50%-0.78%）,1.15%（95%CI:0.93%-1.37%）and 1.48%（95%CI:1.18%-1.78%）;and an increase in COPD emergencies of 0.75%（95%CI:-0.43%-1.94%）,1.53%（95%CI:0.38%-2.69%）,0.46%（95%CI:-0.12%-1.04%）,0.85%（95%CI:0.10%-1.60%）and 1.25%（95%CI:0.27%-2.25%）;and an increase in asthma emergencies of 1.17%（95%CI:0.18%-2.16%）,2.48%（95%CI:1.45%-3.51%）,0.83%（95%CI:0.32%-1.34%）,1.33%（95%CI:0.69%-1.96%）and 1.55%（95%CI:0.67%-2.44%）.No significant gender differences were found in the various types of respiratory diseases,while in the age stratification children aged 0-14 years were found to be more vulnerable to the effects of air pollution than adults and the elderly.4.Stratification by low temperature（t≤17.3℃）and high temperature（t≥27.1℃）revealed that the single-pollutant effects in the total population,males,females,0-14 years and 15-64 years subgroups were all shown to be more detrimental to the onset of respiratory disease in the population at elevated pollutant concentrations at low temperatures than at high temperatures.In the two-pollutant model,gaseous pollutants were more harmful to human respiratory health at low temperatures,while the effect of particulate matter was more pronounced at high temperatures after the introduction of NO₂.5.After stratifying by low humidity（hum<73%）and high humidity（hum>86%）conditions,the study found that elevated SO₂ concentrations were more harmful to the onset of respiratory disease in the population at high humidity than at low humidity.The coexistence of NO₂ and particulate matter with O₃ resulted in a more significant effect of NO₂ and particulate matter at high humidity than at low humidity.The effects of NO₂,PM₁0 and PM₂.5 on each population showed an increase in population respiratory disease emergencies with increasing pollutant concentrations in both low and high humidity conditions,but no between-group differences were observed across humidity conditions for these three pollutants.Conclusion:1.There were significant associations between SO₂,NO₂,O₃,PM₁0 and PM₂.5 concentrations and emergency visits for total respiratory diseases,acute upper respiratory tract infections,bronchitis and asthma in Guangzhou,and NO₂,PM₁0 and PM₂.5 had significant effects on COPD emergency visits,and there were significant lag and cumulative effects of each pollutant on respiratory diseases,while the optimal lag period for different pollutants on the optimal lag period for each type of respiratory disease was not consistent across all categories.2.In the total population,males,females,0-14 years and 15-64 years subgroups,the risk of air pollution on the onset of respiratory diseases was greater at low temperatures than at high temperatures,and gaseous pollutants were more harmful to human respiratory health at low temperatures.3.The effects of NO₂,O₃ and particulate matter on human respiratory health were more pronounced at low relative humidity,while the effects of SO₂ on human respiratory health were more pronounced at high relative humidity,and the coexistence of NO₂ and particulate matter with O₃ would make the effects of NO₂ and particulate matter more pronounced at high humidity compared to low humidity.4.Children<15 years of age are more likely than adults and the elderly to experience acute episodes of respiratory disease due to elevated concentrations of atmospheric pollutants,and the cumulative effects of NO₂ on all types of respiratory disease are more pronounced in children in particular.