Occupational chronic obstructive pulmonary disease attributed to chemicals exposure: Clinical characteristics and inflammatory serum profile

Background. Occupational exposures including toxic gases is one of the major risk factors of chronic obstructive pulmonary disease (COPD). However, clinical features and laboratory-based test markers of COPD attributed to chemicals are still unclear. Objective. To evaluate clinical characteristics and inflammatory serum profile of COPD attributed to chemicals. Methods. A prospective observational study recruited 167 COPD subjects, 42 exposed to aromatic hydrocarbons 55 to dust and 70 tobacco smokers. Controls -105 healthy people. Groups were matched by demographics and smoking status. Serum markers of pulmonary inflammation (by ELISA), blood and sputum eosinophils, decline in FEV1, exacerbations rate, symptoms severity were assessed. Multiple regression model, ROC analysis and area under the curve (AUC) were used to explore the relationships. Results. COPD subjects exposed to chemicals compared to those exposed to dust and tobacco smokers had less exacerbations rates per year (1.2±0.25, 2±0.51 and 3.2±0.32 respectively) but higher severe exacerbations percentage (65%, 24% and 35%), higher prevalence of eosinophilic inflammation (64%, 21% and 43%), less decline in FEV 1 predicted within 3 years (-4.7%±0.51%, -10.7%±1.54% and -22.5±0.74%), p Conclusions. COPD attributed to chemicals have the potential of being a disease phenotype.