Background: The effect of occupational risk factors on the clinical features of COPD is still unclear, and the purpose of this study was to analyze the effect of occupational exposure on the clinical features of COPD. Methods: A total of 908 patients from Grade-A hospitals were analyzed as study subjects, and self-reported occupational exposure was recorded. Results:A total of 258 COPD patients (28.4%) were exposed to VGDF. Several characteristics were significantly associated with VGDF exposure: respiratory symptoms such as cough and sputum, airflow limitation, and mMRC score of 2-4 (41.1%vs32.3%, P＜0.05); CAT score (17.45±1.683 vs 16.61±2.402, P＜0.001). As COPD patients' exposure to occupational factors increased, so did the incidence of respiratory symptoms (P＜ 0.05). Conclusions: In this series of COPD patients, subjects exposed to VDGF had more severe clinical symptoms, including respiratory symptoms, severity of airflow restriction, and CAT score. In occupational risk factor exposure, exposure level is the main influencing factor.

Chronic obstructive pulmonary disease (COPD) results from a complex interaction between genes and the environment, and occupational exposures are an underappreciated risk factor. Until now, little research attention has been paid to the potential impact of occupational risk factor exposure on the COPD in China. The aim of this retrospective study was to analyze the role of occupational risk factor exposure on the severity and progression of COPD for exploring new prevention strategies for this disease. This study adopted a random cluster-sampling method. Five grade-A tertiary hospitals that met the inclusion criteria were selected as the survey sites, and patients with COPD hospitalized in these hospitals from January 1, 2019, to December 31, 2019, were selected as the research subjects. Data of the patients diagnosed with COPD met the Global Initiative for Chronic Obstructive Lung Disease (2019) criteria and were collected from the computerized medical record databases. Among 4082 investigated COPD patients, 1063 (26%) were found to have occupational risk factor exposure history. The top 3 industries with a large COPD case number and a history of occupational risk factor exposure ranked in the order of agriculture (including farming, forestry, animal husbandry, and fishery), manufacturing, and mining. Further multivariate logistic regression analysis indicated that when setting a low exposure level as a reference, medium and high exposure levels were correlated with the severity of COPD (odds ratio values were 2.837 and 6.201, respectively, P < .05). Linear regression analysis showed that cumulative exposure to occupational risk factors was negatively correlated with the forced expiratory volume in 1-second percentage of COPD patients, with a correlation coefficient of 0.68. Our results indicated that occupational risk factor exposure levels were related to the severity of COPD significantly. The incubation period of COPD in the exposure group was significantly shorter than that in the non-exposure group. To prevent worked-related COPD, special attention and control efforts should be taken to reduce the level of occupational risk factors such as organic dust, irritating chemicals, etc in the work environments, especially in the industries of agriculture, forestry, animal husbandry and fishery, manufacturing, and mining.