title: The utility of inflammatory markers to predict readmissions and mortality in COPD cases with or without eosinophilia.
abstract: BACKGROUND
  COPD exacerbations requiring hospitalization increase morbidity and mortality. Although most COPD exacerbations are neutrophilic, approximately 10%-25% of exacerbations are eosinophilic.
  
  
  OBJECTIVE
  We aimed to evaluate mortality and outcomes of eosinophilic and non-eosinophilic COPD exacerbations and identify new biomarkers that predict survival.
  
  
  METHODS
  A retrospective observational cohort study was carried out in a tertiary teaching hospital from January 1, 2014 to November 1, 2014. All COPD patients hospitalized with exacerbations were enrolled in the study at their initial hospitalization and followed-up for 6 months after discharge. Electronic data were collected from the hospital database. Subjects' characteristics, hemogram parameters, CRP levels, neutrophil-to-lymphocyte ratio (NLR), platelet-to-mean platelet volume ratio on admission and discharge, length of hospital stay (days), readmissions, and mortality were recorded. Patients were grouped according to peripheral blood eosinophil (PBE) levels: Group 1, >2% PBE, eosinophilic; Group 2, non-eosinophilic ≤2%. Patient survival after hospital discharge was evaluated by Kaplan-Meier survival analysis.
  
  
  RESULTS
  A total of 1,704 patients hospitalized with COPD exacerbation were included. Approximately 20% were classified as eosinophilic. Six-month mortality was similar in eosinophilic and non-eosinophilic groups (14.2% and 15.2%, respectively); however, the hospital stay length and readmission rate were longer and higher in the non-eosinophilic group (P<0.001 and P<0.01, respectively). CRP and NLR were significantly higher in the non-eosinophilic group (both P<0.01). The platelet-to-mean platelet volume ratio was not different between the two groups. Cox regression analysis showed that survival was negatively influenced by elevated CRP (P<0.035) and NLR (P<0.001) in the non-eosinophilic group.
  
  
  CONCLUSIONS
  Non-eosinophilic patients with COPD exacerbations with high CRP and NLR values had worse outcomes than eosinophilic patients. PBE and NLR can be helpful markers to guide treatment decisions.
authors.affiliation: Sureyyapasa Chest Diseases and Thoracic Surgery Teaching Hospital, Istanbul, Turkey.
authors.forename: Dildar
authors.initials: D
authors.lastname: Duman
authors.affiliation: Sureyyapasa Chest Diseases and Thoracic Surgery Teaching Hospital, Istanbul, Turkey.
authors.forename: Emine
authors.initials: E
authors.lastname: Aksoy
authors.affiliation: Sureyyapasa Chest Diseases and Thoracic Surgery Teaching Hospital, Istanbul, Turkey.
authors.forename: Meltem Coban
authors.initials: MC
authors.lastname: Agca
authors.affiliation: Sureyyapasa Chest Diseases and Thoracic Surgery Teaching Hospital, Istanbul, Turkey.
authors.forename: Nagihan Durmus
authors.initials: ND
authors.lastname: Kocak
authors.affiliation: Sureyyapasa Chest Diseases and Thoracic Surgery Teaching Hospital, Istanbul, Turkey.
authors.forename: Ipek
authors.initials: I
authors.lastname: Ozmen
authors.affiliation: Sureyyapasa Chest Diseases and Thoracic Surgery Teaching Hospital, Istanbul, Turkey.
authors.forename: Ulku Aka
authors.initials: UA
authors.lastname: Akturk
authors.affiliation: Sureyyapasa Chest Diseases and Thoracic Surgery Teaching Hospital, Istanbul, Turkey.
authors.forename: Sinem
authors.initials: S
authors.lastname: Gungor
authors.affiliation: Sureyyapasa Chest Diseases and Thoracic Surgery Teaching Hospital, Istanbul, Turkey.
authors.forename: Fatma Merve
authors.initials: FM
authors.lastname: Tepetam
authors.affiliation: Sureyyapasa Chest Diseases and Thoracic Surgery Teaching Hospital, Istanbul, Turkey.
authors.forename: Selma Aydogan
authors.initials: SA
authors.lastname: Eroglu
authors.affiliation: Sureyyapasa Chest Diseases and Thoracic Surgery Teaching Hospital, Istanbul, Turkey.
authors.forename: Selahattin
authors.initials: S
authors.lastname: Oztas
authors.affiliation: Sureyyapasa Chest Diseases and Thoracic Surgery Teaching Hospital, Istanbul, Turkey.
authors.forename: Zuhal
authors.initials: Z
authors.lastname: Karakurt
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D001792:Blood Platelets / Q000276:immunology; D002097:C-Reactive Protein / Q000276:immunology; D016009:Chi-Square Distribution; D018450:Disease Progression; D005260:Female; D006784:Hospitals, Teaching; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood / Q000276:immunology*; D053208:Kaplan-Meier Estimate; D018655:Lymphocyte Count; D008214:Lymphocytes / Q000276:immunology; D008297:Male; D063847:Mean Platelet Volume; D008875:Middle Aged; D009504:Neutrophils / Q000276:immunology; D010359:Patient Readmission; D010976:Platelet Count; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood / Q000175:diagnosis* / Q000276:immunology* / Q000401:mortality / Q000628:therapy; D011657:Pulmonary Eosinophilia / Q000097:blood / Q000175:diagnosis* / Q000276:immunology* / Q000401:mortality / Q000628:therapy; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D062606:Tertiary Care Centers; D013997:Time Factors; D014421:Turkey
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D002097:C-Reactive Protein
keywords: chronic obstructive pulmonary disease; exacerbation; mortality; peripheral eosinophilia