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

Emine Aksoy, Zuhal Karakurt, Sinem Gungor, Birsen Ocakli, İpek Ozmen, Elif Yildirim, Eylem Tuncay, Meltem Coban Agca, Nezihe Ciftaslan Goksenoglu, Nalan Adigüzel Respiratory Intensive Care Unit Clinic, Sureyyapasa Chest Diseases and Thoracic Surgery Teaching and Research Hospital, Istanbul, Turkey Background: 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. Method: 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 <2%), and further subdivided according to place of admission (outpatient clinic, ward, or intensive care unit [ICU]) as an indicator of disease severity. Complete blood count, biochemistry, C-reactive protein (CRP), NLR, PLR, and platelet to mean platelet volume values were recorded from an electronic hospital database system and compared among all groups. Results: Of the 10,592 patients included in the study, 7,864 were admitted as outpatients, 2,233 to the wards, and 495 to ICU. Neutrophilic COPD patients (n=6,536, 62%) had increased inflammatory markers compared with eosinophilic COPD patients (n=4,056, 38%); median NLR was 5.11 vs 2.62 (P<0.001), PLR was 175.66 vs 130.00 (P<0.001), and CRP was 11.6 vs 7.7 (P<0.001). All values increased relative to admission to the outpatient clinic, ward, or ICU: median NLR was 3.20, 6.33, and 5.94, respectively, median PLR was 140.43, 208.46, and 207.39, respectively, and median CRP was 6.4, 15.0, and 22.8, respectively. The median NLR values of patients in outpatients/ward/ICU increased in neutrophilic and eosinophilic endotypes: 4.21/7.57/8.60 (P<0.001) and 2.50/3.43/3.42 (P=0.81), respectively. CRP showed a similar increased pattern according to severity of AECOPD endotypes. Conclusion: In COPD exacerbation, the inflammatory markers show different increases in each COPD endotypes. These findings may be crucial for defining exacerbation endotypes, the severity of exacerbation, and treatment response during follow-up in COPD patients. Keywords: outpatients, inflammatory biomarkers, COPD attack, ward and intensive care, hospitalizatio

Does eosinophilic COPD exacerbation have a better patient outcome than non-eosinophilic in the intensive care unit?

Cüneyt Saltürk, Zuhal Karakurt, Nalan Adiguzel, Feyza Kargin, Rabia Sari, M Emin Celik, Huriye Berk Takir, Eylem Tuncay, Ozlem Sogukpinar, Nezihe Ciftaslan, Ozlem Mocin, Gokay Gungor, Selahattin OztasRespiratory Intensive Care Unit, Sureyyapasa Chest Diseases and Thoracic Surgery Teaching Hospital, Istanbul, TurkeyBackground: COPD exacerbations requiring intensive care unit (ICU) admission have a major impact on morbidity and mortality. Only 10%–25% of COPD exacerbations are eosinophilic.Aim: To assess whether eosinophilic COPD exacerbations have better outcomes than non-eosinophilic COPD exacerbations in the ICU.Methods: This retrospective observational cohort study was conducted in a thoracic, surgery-level III respiratory ICU of a tertiary teaching hospital for chest diseases from 2013 to 2014. Subjects previously diagnosed with COPD and who were admitted to the ICU with acute respiratory failure were included. Data were collected electronically from the hospital database. Subjects’ characteristics, complete blood count parameters, neutrophil to lymphocyte ratio (NLR), delta NLR (admission minus discharge), C-reactive protein (CRP) on admission to and discharge from ICU, length of ICU stay, and mortality were recorded. COPD subjects were grouped according to eosinophil levels (>2% or ≤2%) (group 1, eosinophilic; group 2, non-eosinophilic). These groups were compared with the recorded data.Results: Over the study period, 647 eligible COPD subjects were enrolled (62 [40.3% female] in group 1 and 585 [33.5% female] in group 2). Group 2 had significantly higher C-reactive protein, neutrophils, NLR, delta NLR, and hemoglobin, but a lower lymphocyte, monocyte, and platelet count than group 1, on admission to and discharge from the ICU. Median (interquartile range) length of ICU stay and mortality in the ICU in groups 1 and 2 were 4 days (2–7 days) vs 6 days (3–9 days) (P<0.002), and 12.9% vs 24.9% (P<0.034), respectively.Conclusion: COPD exacerbations with acute respiratory failure requiring ICU admission had a better outcome with a peripheral eosinophil level >2%. NLR and peripheral eosinophilia may be helpful indicators for steroid and antibiotic management.Keywords: chronic obstructive pulmonary disease, exacerbation, respiratory failure, intensive care unit, peripheral eosinophili