Objectives To assess the association between chronic obstructive pulmonary disease (COPD) comorbidities and clinical characteristics, and to explore the inflammation mechanism. Methods 220 stable COPD patients were included. Clinical characteristics and comorbidities were recorded, and blood samples were collected. The relationship among the number and type of comorbidities, Charlson comorbidity index (CCI), clinical characteristics and the levels of plasma inflammatory markers 〔interleukin (IL)-6, high sensitivity C-reaction protein (hs-CRP), tumor necrosis factor-α (TNF-α), IL-8〕 were studied. Results The top five comorbidities were hypertension, metabolic syndrome and diabetes osteoporosis, bronchiectasis and peripheral vascular diseases. The level of plasma IL-6 was greater in higher CCI score (≥4) group compared with lower CCI score (<4) group ( P=0.011). Levels of IL-6 and IL-8 and the number of hospitalization in prior year were positively correlated with CCI and age adjusted CCI (r<0.03, P<0.05). There was a correlation between the COPD comorbidities and systemic inflammatory response (r<0.3, P<0.05). Conclusion Patients with a higher CCI score had more severe symptoms, functional impairment and higher level of inflammatory factors and high frequency of hospital admission due to acute exacerbation. The mechanism by which COPD may play a role in systemic inflammatory response deserves further study.
