Inflammation and comorbidities of chronic obstructive pulmonary disease: The cytokines put on a mask!

Chronic obstructive pulmonary disease (COPD) is a well-known complex multicomponent disease characterized by systemic inflammation that frequently coexists with other conditions. We investigated the relationship between some inflammatory markers and complications in COPD patients to explore the possible roles of inflammation in these comorbidities. This study used cross-sectional and case-control methods. We included 336 hospitalized COPD patients, 64 healthy controls, and 42 major depression patients and evaluated all participants using the Hamilton Rating Scale. C-reactive protein (CRP), red blood cell distribution width (RDW), neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), monocyte/lymphocyte ratio (MLR), interleukin-1β (IL-1β) and interleukin-6 (IL-6) were collected and measured in the study population. Statistical methods were used to analyze the association of inflammatory markers with COPD comorbidities. Cor pulmonale and psychological comorbidities (depression and anxiety) were more common in this study on COPD patients. We found that MLR (OR = 2.054, 95 % CI 1.129–3.735, p = 0.018) and RDW (OR = 1.367, 95 % CI 1.178–1.586, p = 0.000) were related to COPD patients complicated with cor pulmonale, while IL-6 (OR = 1.026, 95 % CI 1.001–1.053, p = 0.045) and RDW (OR = 1.280, 95 % CI 1.055–1.552, p = 0.012) were related to depression symptoms. MLR, RDW and IL-6 were closely related to cor pulmonale and depression in COPD patients. IL-1 β and IL-6 are closely related to depression in humans.