The Impact Of Outdoor Air Pollution In Beijing On The Hospitalization Rate, Lung Function And Systemic Inflammation Of Patients With Chronic Obstructive Pulmonary Disease

Part Ⅰ Short-term effects of ambient air pollution on chronic obstructive pulmonary disease admissions in Beijing,ChinaPurpose:In this study,we aimed to explore the effects of air pollutants on chronic obstructive pulmonary disease(COPD)admissions in Beijing,China.Methods:Daily COPD hospital admission visits derived from tertiary and secondary hospitals in Beijing were retrieved from January 2013 to February 2017.Air pollutant levels and meteorological data over the same periods were also achieved.Generalized additive model was applied to estimate the percentage changes with 95%confidence interval(95%CI)in daily admissions corresponding to 10 μg/m3 increases in pollutants levels(1 mg/m3 in carbon monoxide(CO)),stratified by age,gender and season.Results:Seventy-three thousand seventy-six COPD hospital admission visits were included with mean daily visits of 48(21).Gaseous air pollutants had larger adverse effects on hospitalization than particulate matters.Cumulative lag effect with per 10μg/m3 increase in air pollutant levels was largest for nitrogen dioxide(NO2)with 3.03%(95%CI:1.82%-4.26%)at lag06,for sulfur dioxide(S02)with 2.07%(95%CI:1.00%-3.15%)at lag01,for particulate matter≤10μm in aerodynamic diameter(PM10)with 0.92%(95%CI:0.55%-1.30%)at lag07,and for particulate matter≤2.5 μm in aerodynamic diameter(PM2.5)with 0.82%(95%CI:0.38%-1.26%)at lag06,respectively.Percentage increase for each 1 mg/m3 increase in CO was 5.99%(95%CI:2.74%-9.34%)at lag06.However,we found no association between ozone(O3)and COPD hospitalization:Further,stronger effects of air pollution on COPD admissions were found in warm seasons than in cold seasons.Conclusion:Short-term exposures to PM2.5,PM10,NO2,SO2 and CO had adverse effects on COPD hospitalizations in Beijing,with higher effects for gaseous pollutants.Part Ⅱ Short-term effects of ambient air pollution on lung function and systemic inflammation among chronic obstructive pulmonary disease patients in Beijing,ChinaPurpose:To evaluate the effects of ambient air pollution on lung function,quality of life and serum cytokines among COPD patients in Beijing,China.Methods:We enrolled COPD and healthy participants in Beijing city from December 2015 to September 2017.Each participant was scheduled to visit the hospital every 3 months for 2-year follow up.Blood samples,spirometry tests and evaluations on quality of life(the MOS 36-item short form health survey(SF-36)and St George’s respiratory questionnaire(SGRQ))were collected.Meanwhile,the levels of 20 serum cytokines were detected by Milliplex method.Air pollutant levels and meteorological data over the same periods were also achieved.We applied the linear mixed-effect model to evaluate the health effects of air pollutants on COPD and healthy subjects during the first-year observation.Results:84 COPD patients and 64 healthy volunteers were enrolled at baseline.Of those,75 COPD patients and 64 healthy subjects completed the first-year follow-up.We found adverse cumulative effects of PM2.5,NO2,SO2 and CO on the forced vital capacity%predicted(FVC%pred)in patients with COPD.For the forced expiratory volume in one second%predicted(FEV1%pred),FVC and FEV1,the effects were insignificant.In healthy group,the decrements of pulmonary function were only correlated with SO2 exposure.Additionally,PM2.5,PM10,NO2,SO2 and CO exposures increased the SGRQ scores among COPD patients.PM2.5,PM10 and CO exposures decreased the SF-36 scores for heathy participants.Further analyses illustrated that,among COPD patients,elevated levels of air pollutant were associated with reduced levels of serum Eotaxin,interleukin 4(IL-4)and IL-13,and correlated with increased white blood cell counts,neutrophils counts,serum IL-2,IL-12,IL-17A,interferon y,monocyte displacing protein 1(MCP-1)and soluble CD40 ligand(sCD40L)levels.These effects were not found in healthy group,except that NO2 exposure was correlated with higher IL-17A levels.Conclusion:(1)Acute exposures of PM2.5,NO2.SO2 and CO were associated with reduction of FVC%pred among COPD patients.For healthy group,decreased pulmonary function was only correlated with SO2.(2)PM2.5,PM10,NO2,SO2 and CO exposures were associated with the increased SGRQ scores in COPD patients.For the healthy participants,PM2.5.PM10 and CO levels were adversely correlated with SF-36 scores.Our study suggested air pollution was associated with the decreases of quality of life for both COPD and healthy participants.(3)Short-term exposures of air pollutants increased the levels of serum Thl and Th17 typical cytokines and decreased the concentrations of serum Th2 typical cytokines,which indicated air pollution may enhance the systemic inflammation among COPD patients.