Association Of Dust/Harmful Gas Exposure With Pulmonary Ventilation Function And COPD Among Middle-aged And Elderly Population In Guangdong Province

ObjectivesTo explore the association between occupational dust/harmful gas exposure and respiratory symptoms and pulmonary dysfunction,and to analyze the effect of occupational dust/harmful gas exposure on the risk of chronic obstructive pulmonary disease（COPD）.To provide reference for strengthening occupational protection measures of occupational dust/harmful gas exposure in Guangdong Province.MethodsThe subjects were from two independent cross-sectional surveys of“Chronic Obstructive Pulmonary Disease Surveillance of Residents in Guangdong Province”in 2014-2015 and 2019.A total of 7510 permanent residents aged≥40 years were selected twice by multi-stage stratified cluster random sampling.Data were collected by questionnaire,physical examination and pulmonary function test.Occupational exposure was divided into four groups（unexposed group,dust exposure group,harmful gas exposure group and dust+harmful gas dual exposure group）.The differences of occupational exposure,respiratory symptoms,pulmonary ventilation function and COPD（sick or not）were compared between groups.The continuous variables were analyzed by t test/F test,and the categorical variables were analyzed byχ² test.Univariate and multivariate logistic regression models were used to analyze the effects of occupational dust/harmful gas exposure on respiratory symptoms and COPD,and multiple linear regression models were used to analyze the quantitative relationship between occupational dust/harmful gas exposure and various indicators of pulmonary ventilation function.Results（1）The exposure rate of occupational dust,harmful gas and dual among residents aged≥40 years in Guangdong Province were 12.29%,8.60%and 22.23%respectively.The detection rates of cough,phlegm,wheezing and dyspnea among residents aged≥40 years in Guangdong Province were 7.89%,12.05%,8.51%and 3.68%,respectively.The detection rate of COPD was 12.08%.（2）After adjusting for confounding factors,dust exposure was associated with an increased risk of cough（OR=1.57,95%CI:1.20～2.03）,phlegm（OR=1.49,95%CI:1.19～1.85）and dyspnea（OR=1.68,95%CI:1.06～2.58）.Exposure to harmful gas was associated with an increased risk of cough（OR=1.51,95%CI:1.10～2.04）,wheezing（OR=1.42,95%CI: 1.04～1.92）and dyspnea（OR=2.13,95%CI:1.36～3.25）.Dual exposure was associated with an increased risk of cough（OR=1.41,95%CI:1.13～1.76）,phlegm（OR=1.47, 95%CI:1.23～1.76）,wheezing（OR=2.01,95%CI:1.65～2.45）,and dyspnea（OR=2.95, 95%CI:2.19～3.98）.（3）After adjusting for confounding factors,harmful gas exposure was associated with the decrease of pulmonary ventilation function indexes FEV₁/FVC（β=-0.98%,95%CI:-1.77 ～-0.19）and MMEF（β=-0.15 L/s,95%CI:-0.23～-0.07）.Dual exposure was associated with the increase of pulmonary ventilation function index FVC（β=0.04 L,95%CI:0.01～ 0.07）and the decrease of FEV₁/FVC（β=-0.74%,95%CI:-1.27～-0.21）and MMEF（β= -0.06 L/s,95%CI:-0.12～-0.01）.（4）After adjusting for confounding factors,occupational dust/harmful gas exposure was not associated with the increased risk of COPD,nor was there an association between gender and urban-rural stratification.（5）In males,dust exposure and dual exposure were risk factors for respiratory symptoms,while harmful gas exposure was associated with pulmonary dysfunction;In females,exposure to harmful gas and dual exposure were both risk factors for respiratory symptoms and associated with pulmonary dysfunction.（6）In urban residents,dust exposure and dual exposure were risk factors for respiratory symptoms,and exposure to harmful gas was associated with pulmonary dysfunction.Among rural residents,dust exposure,harmful gas exposure,and dual exposure were associated with an increased risk of respiratory symptoms,with both exposure to harmful gas and dual exposure were also risk factors for pulmonary dysfunction.Conclusions（1）In Guangdong Province,the exposure rate of occupational dust/harmful gas was high among residents aged≥40 years,but the proportion of taking protective measures was low.（2）The association between occupational dust/harmful gas exposure and COPD has not been found,but occupational dust/harmful gas exposure is a risk factor for respiratory symptoms and pulmonary dysfunction in residents aged≥40 years in Guangdong Province,and the harm caused by continuous occupational exposure to lung may develop COPD later.（3）The association between occupational dust/harmful gas exposure and respiratory symptoms and pulmonary dysfunction showed different characteristics after gender and urban-rural stratification.More attention should be paid to the health of occupationally exposed people in rural areas.