The Correlation Between Atmospheric Pollutants And Pulmonary Sepsis And The Lag-effects

Objective:Since recent times,exposure to atmospheric pollutants has been considered one of the key threats to human health,which can cause respiratory damage.However,the relationship between pulmonary sepsis and atmospheric pollutants remains unclear.This study aims to provide a new clinical strategy for the prevention and treatment of pulmonary sepsis by exploring the correlation and Lag-effects（Lag）between the level of atmospheric pollutants and the incidence of pulmonary sepsis.Methods:A total of 336 patients with pulmonary sepsis admitted to the Second Clinical Medical College of Jinan University（Shenzhen People’s Hospital）from January 1,2018 to December 31,2020 were enrolled.All subjects were analyzed as a whole,and then stratified by age,sex,and season of onset.（1）Age stratification:young adult group（18-59 years old）and elderly group（≥60 years old）;（2）Gender stratification:male group and female group;（3）Stratification of onset seasons:onset of cold season group（December-April of the next year）,and onset of warm season group（May-November）.General clinical information of all subjects was collected including gender,age,smoking history,complications,length of hospital stay,and 28-day mortality.The average daily concentration of atmospheric pollutants(PM₁、PM_2.5、PM₁₀、NO₂、SO₂、CO、O₃)and meteorological data in Shenzhen during the onset period were also included.SPSS 26.0statistical software was used for analysis and processing.T test or rank sum test was used for comparison of measurement data between groups,X² test for comparison of count data,and Spearman correlation analysis for correlation between atmospheric pollutants and meteorological factors.A time-stratified case crossover study model constructed for each group,and the exposure levels of atmospheric pollutants were substituted into the same patient on the onset day（Lag0）and within 7 days before onset（Lag1-Lag7）.The annual average daily concentration of atmospheric pollutants was taken as the control.Univariate and multivariate logistic regression were used to analyze the correlation and lag effect between exposure to atmospheric pollutants and the incidence of pulmonary sepsis.The optimal lag time was determined according to the principle of maximum OR value,and P<0.05 was considered as statistically significant difference.Results:（1）From 2018 to 2020,air quality of Shenzhen was excellent.Compared with China Air Quality Standard（AQS,GB3095-2012）Class 1,only the levels of PM2.5 and SO2 were slightly over the standard,and the levels of other atmospheric pollutants were far below the standard.The concentrations of PM1,PM2.5 and PM10 in the atmosphere of Shenzhen showed obvious characteristics of seasonal variations.High concentrations in cold season and low concentrations in warm season were presented.PM₁,PM2.5 and PM10 were positively correlated with each other（r>0.8）,while no correlation between NO2,SO2,CO,O3（r all<0.8）,and meteorological factors（including temperature and relative humidity）were found（r>-0.8）.（2）As to all the patients with systemic pulmonary sepsis:（1）PM₁ on Lag6 was positively correlated with the incidence of pulmonary sepsis,OR with 1.742,and P values with 0.014.（2）O3 from Lag4 to Lag6 was positively correlated with the incidence of pulmonary sepsis（P all<0.05）,and the OR values were 1.815,1.769 and 2.090,respectively.The optimal lag time was Lag6.（3）As to the patients with pulmonary sepsis at different ages:（1）PM₁ on Lag2 and Lag6 were both positively correlated with the incidence of elderly patients with pulmonary sepsis（both P<0.05）,and the OR values were 2.500 and 1.833,respectively.The optimal lag was Lag2.PM₁on Lag6 was an independent risk factor for the disease.（2）PM_2.5 on Lag2 was positively correlated with the incidence of elderly patients with pulmonary sepsis,OR with 2.222,and P values with 0.046.（3）PM₁₀ on Lag4 was positively correlated with the incidence of elderly patients with pulmonary sepsis,OR with 2.492,and P values with 0.048.（4）O₃on Lag6 was positively correlated with the incidence of elderly patients with pulmonary sepsis,OR with 2.091,and P values with 0.044.O₃on Lag6 was an independent risk factor for the disease.（5）O₃ from Lag3 to Lag7 were positively correlated with the incidence of young patients with pulmonary sepsis（P all<0.05）,and the OR values were 2.300,2.455,2.083,4.167 and 2.300,respectively.The optimal lag was Lag6.O3 from Lag3 to Lag7 were independent risk factors for the disease.（4）As to the patients with pulmonary sepsis with different genders:（1）PM₁ on Lag6 was correlated with the incidence of male patients with pulmonary sepsis,OR with 2.333,and P with0.006.PM₁ on Lag6 was an independent risk factor for the disease.（2）O₃on Lag5 and Lag6 were correlated with the incidence of male patients with pulmonary sepsis（both P<0.05）,and the OR values were 1.882 and 2.133,respectively.The optimal lag was Lag6.O3 on Lag5 and Lag6 were independent risk factors for the disease.（3）O₃on Lag4 and Lag6 were both correlated with the incidence of female patients with pulmonary sepsis（both P<0.05）,and the OR values were 2.625and 2.429,respectively.The optimal lag was Lag4.O3 on Lag4 and Lag6 were independent risk factors for the disease.（5）As to the patients with pulmonary sepsis in different onset seasons:（1）PM₁ on Lag6 was positively correlated with the incidence of pulmonary sepsis in warm seasons,OR with 2.000,and P with 0.023.PM₁ on Lag6 was an independent risk factor for the disease.（2）PM_2.5 on Lag7was positively correlated with the incidence of pulmonary sepsis in warm seasons,OR with2.571,and P with 0.034.PM_2.5 on Lag7 was an independent risk factor for the disease.（3）O₃on Lag6 and Lag7 were both positively correlated with the incidence of pulmonary sepsis in warm seasons,OR with 2.056,and P with 1.947.O3 on Lag6 and Lag7 were independent risk factors for the disease.（4）PM₁ on Lag2 was positively correlated with the incidence of pulmonary sepsis in cold seasons,OR with 2.143,and P with 0.018.PM1 on Lag2 was an independent risk factor for the disease.（5）O₃on Lag1 and Lag6 were both related with the incidence of pulmonary sepsis in cold seasons,（both P<0.05）,and the OR values were 8.500 and 9.000,respectively.O3 on Lag1 and Lag6 were both independent risk factors for the disease.Conclusion:（1）Exposure to PM1 and PM2.5 on Lag2,PM10 on Lag4,and O3 on Lag6 had the most significant correlated with the incidence of pulmonary sepsis in elderly patients.Exposure to PM1 and O3 on Lag6 were both independent risk factors for the disease.Lag6 O3 exposure had the most significant correlated with the incidence of pulmonary sepsis in young adults,and it was an independent risk factor for the disease.（2）PM1 and O3 exposure on Lag6 had the most correlated with the incidence of pulmonary sepsis in male patients,and they were independent risk factor for the disease.Meanwhile,O3exposure on Lag4 had the most significant correlated with the incidence of pulmonary sepsis in female patients with pulmonary sepsis,and it was an independent risk factor for the disease.（3）PM1,O3 and PM2.5 exposure on Lag6 and Lag7 had the most significant correlated with the incidence of pulmonary sepsis in warm season,and they were independent risk factors for the disease.Meanwhile,PM1 and O3 exposure on Lag2 had the most significant correlated with the incidence of pulmonary sepsis in cold season,and it was an independent risk factor for the disease.