Neutrophil to lymphocyte ratio is a better indicator of COPD exacerbation severity in neutrophilic endotypes than eosinophilic endotypes

Complete blood count parameters provide novel inflammatory markers, namely neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR). We aimed to assess any differences in these novel inflammatory markers according to exacerbation severity in patients with COPD in both eosinophilic and neutrophilic endotypes. This retrospective cross-sectional study was conducted at a tertiary education hospital. Previously diagnosed COPD patients admitted to the hospital with acute COPD exacerbation (AECOPD) were enrolled into the study. Patients were grouped according to COPD endotype, eosinophilic (peripheral blood eosinophil rate ≥2%) and neutrophilic (peripheral blood eosinophil rate