Study of inflammatory markers and BODE index in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a common preventable and treatable disease characterized by progressive airflow limitation and associated with enhanced chronic inflammatory response of the airways to a variety of noxious stimuli. The current concept of COPD, however, extends beyond the respiratory system to include a variety of extrapulmonary manifestations which includes raised inflammatory markers.

This was a single, center observational open-labeled case-controlled study which included fifty patients of diagnosed COPD and 50 age- and gender-matched controls. All patients were evaluated by detailed history taking, pulmonary function test, 6-min walk test, and calculation of BODE scores. Levels of serum inflammatory markers such as cortisol, tumor necrosis factor alpha, interleukin-6 (IL-6), lactate dehydrogenase, and C-reactive protein were estimated using standard quality equipments.

Majority of the patients in the study and control groups were males and were aged above 40 years. Thirty-eight of the fifty COPD patients had BODE scores of more than 3. All the studied inflammatory markers were significantly higher in the COPD group as compared to the control group. Of all the studied markers, only IL-6 showed a significant correlation with BODE index, i.e., higher IL-6 values were associated with higher BODE scores. No correlation was seen between the other markers and BODE scores.

Our data suggest that IL-6 is a biomarker that correlates with BODE score. IL-6 as a target for therapy in COPD needs to be further studied. Follow-up studies are needed to validate findings.