[Clinical feature analysis of 258 COPD patients with a history of occupational hazard exposure]

Objective: Analyze the correlation between exposure to occupational hazard factors and clinical characteristics of chronic obstructive pulmonary disease (COPD) to provide a basis for early identification and prevention of occupational-related COPD. Methods: In May 2020, a study was conducted involving 258 chronic obstructive pulmonary disease (COPD) patients with occupational exposure history from three general hospitals in Jinan City. Such as symptoms, signs and the percentage of forced expiratory volnmein one second to predicted valve (FEV(1)%pred) collectted exposure to occupational hazard factors such as length of strvice and types of exposure. Clinical characteristics were analyzed through questionnaire surveys and COPD-related data collection. Group comparisons employed t-tests or F-tests, while non-parametric tests were applied to non-normal distribution data. Differences in categorical variables between groups were examined using χ(2)-tests or Fisher's exact test. Multivariate analysis was performed using generalized linear models, with normal distribution correlation analyses conducted through linear regression. Results: Among 258 patients, 145 were male (56.2%) and 113 were female (43.8%), with 210 being smokers (81.4%). The exposure dust primarily consisted of plant-based organic dust (157 cases, 75.5%) and carbon-containing inorganic dust (24 cases, 11.5%). The majority (94 cases, 36.4%) were diagnosed in the 60+ age group. Regarding pulmonary function severity, 55 patients (21.3%) had mild airflow limitation, 99 (38.4%) moderate, 64 (24.8%) severe, and 40 (15.5%) very severe. For acute exacerbation hospitalizations within the past year, 195 (75.6%) had fewer than 2 hospitalizations, while 63 (24.4%) had more than 2. Comprehensive severity assessment showed most patients (91 cases, 35.3%) were in Group B and 62 (24.0%) in Group D. mMRC scores ranged from 0-1 (58.9%) and 2-4 (106 cases, 41.1%). The average CAT questionnaire score was 17.45±1.68. Respiratory symptoms significantly increased with higher occupational hazard exposure levels (P<0.05). Moderate-to-high risk exposure showed a correlation with disease severity, with OR values (95%CI) of 1.30 (1.10-1.53) and 1.38 (1.20-1.59). There was a certain correlation between high risk exposure and the number of acute exacerbations in COPD patients in the past year, OR value (95%CI) was 1.410 (1.33-1.50) . Conclusion: Contact level is a major hazard factor affecting COPD respiratory symptoms, disease severity, and number of acute exacerbations. Older age at diagnosis, lower literacy, more smoking and higher exposure level, patients had worse lung function and more severe clinical symptoms.