Correlations Between Inflammatory Biomarkers and COPD Severity in a Real-Life Setting

Background: With a steady increase in prevalence, chronic obstructive pulmonary disease (COPD) is recognized as a leading contributor to global mortality, which underscores the need to identify prognostic biomarkers that are easy to use in everyday practice. As both local and systemic inflammation play a pivotal part in the development and progression of COPD, the purpose of our study was to assess the role of inflammatory markers in estimating disease severity (GOLD 1 to 4) to guide the management and treatment of patients with COPD, thus helping to reduce episodes of decompensation and fatal outcomes in both immediate and long-term contexts. Methods: We performed a descriptive observational analysis with a cross-sectional design including 100 patients with stable COPD. All subjects underwent standard clinical examination, lung function tests and a comprehensive inflammation blood panel. Results: We included 55 patients with mild-moderate COPD (GOLD 1-2), 33 patients with advanced stages of COPD (GOLD 3) and 12 patients with very severe forms of the disease (GOLD 4). Male sex, smoking status, BMI, IL-1 beta, NLR, and nocturnal heart rate were parameters with significant value for assessing COPD severity (p < 0.05 for all). NLR correlates significantly with the predicted distance in the 6 MWT (p = 0.039). Significant associations were identified between IL-8 and duration of exposure of biomass fuel (p = 0.045) as well as between IL-6 and pack-years (p = 0.024), with both prognostic and therapeutic impact. Furthermore, the analysis of the total cohort revealed positive correlations between serum IL-6 and FVC (%) (p = 0.033) or NLR and the ratio between FEV1 and FVC (p = 0.048). The neutrophil-to-lymphocyte ratio (NLR) proved to be a reliable indicator of stages 3-4 GOLD (AUC 0.66, threshold value 2.3045, p = 0.004-a one-point increase in NLR corresponded to a 2.148 increase in FEV1). Conclusions: NLR emerged as a simple, accessible and highly informative biomarker in COPD, linked to disease severity and functional decline. Its integration into routine assessment could enhance prognosis and guide clinical decisions, a finding that warrants confirmation in future multicenter studies.