title: Prognostic value of neutrophil to lymphocyte ratio in patients with acute pulmonary embolism: a restrospective study.
abstract: BACKGROUND
  Acute pulmonary embolism (PE) is a serious clinical condition characterised by a high mortality rate. Previous studies showed that leukocytosis was associated with recurrences of venous thromboemboli, major bleeding and increased mortality. The aim of the present study was to investigate the prognostic value of neutrophil to lymphocyte ratio (NLR) in patients with acute PE during short term follow-up.
  
  
  METHODS
  A total of 640 patients were screened by I26 code of ICD-9 and 359 patients were included as cases of confirmed acute PE. Admission blood counts and clinical data were obtained from medical charts. The predictors of 30-day mortality were examined.
  
  
  RESULTS
  Fifty-one out of 359 patients (14.2%) included in the study died during 30 days follow-up. In multivariate Cox regression analysis systolic blood pressure (HR:0.97 (0.94-0.99 CI95%), p=0.019), diabetes mellitus (HR:3.3 (1.30-8.39 CI95%), p=0.012), CK-MB(HR:1.03 (1.01-1.06 CI95%), p=0.024) and NLR (HR:1.03 (1.01-1.06 CI95%), p=0.008) were predictors of 30-day mortality. An optimal cut-off value of NLR was determined as 9.2 by using ROC curve. Hazards ratio of NLR>9.2 was found to be 3.60 (1.44-9.18 CI95%, p=0.006). NLR>9.2 had a sensitivity, specificity, negative predictive value, and positive predictive value of 68.6%, 80.5%, 93.9% and 36.5%, respectively.
  
  
  CONCLUSIONS
  NLR on hospital admission may be a predictor of 30-day mortality in acute PE. Since complete blood count is a part of the routine laboratory investigation in the most hospitalised patients use and preliminary promising results of this study, NLR should be investigated in future prospective randomised trials regarding prognostic value in acute PE.
authors.affiliation: Department of Cardiology, Meram School of Medicine Konya Necmettin Erbakan University, Konya, Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Kayrak
authors.affiliation: Department of Cardiology, Meram School of Medicine Konya Necmettin Erbakan University, Konya, Turkey. Electronic address: drhalilibrahimerdogan@gmail.com.
authors.forename: Halil Ibrahim
authors.initials: HI
authors.lastname: Erdoğan
authors.affiliation: Department of Nephrology, Meram School of Medicine Konya Necmettin Erbakan University, Konya, Turkey.
authors.forename: Yalcin
authors.initials: Y
authors.lastname: Solak
authors.affiliation: Department of Cardiology, Meram School of Medicine Konya Necmettin Erbakan University, Konya, Turkey.
authors.forename: Hakan
authors.initials: H
authors.lastname: Akilli
authors.affiliation: Department of Cardiology, Meram School of Medicine Konya Necmettin Erbakan University, Konya, Turkey.
authors.forename: Enes Elvin
authors.initials: EE
authors.lastname: Gül
authors.affiliation: Department of Cardiology, Meram School of Medicine Konya Necmettin Erbakan University, Konya, Turkey.
authors.forename: Oğuzhan
authors.initials: O
authors.lastname: Yildirim
authors.affiliation: Department of Cardiology, Meram School of Medicine Konya Necmettin Erbakan University, Konya, Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Erer
authors.affiliation: Department of Emergency Medicine, Konya Education and Research Hospital, Konya, Turkey.
authors.forename: Nezire Belgin
authors.initials: NB
authors.lastname: Akilli
authors.affiliation: Department of Pulmonary Medicine, Konya Education and Research Hospital, Konya, Turkey.
authors.forename: Taha Tahir
authors.initials: TT
authors.lastname: Bekci
authors.affiliation: Department of Cardiology, Meram School of Medicine Konya Necmettin Erbakan University, Konya, Turkey.
authors.forename: Alpay
authors.initials: A
authors.lastname: Aribaş
authors.affiliation: Department of Cardiology, Meram School of Medicine Konya Necmettin Erbakan University, Konya, Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Yazici
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D018655:Lymphocyte Count; D008214:Lymphocytes; D008297:Male; D008875:Middle Aged; D009504:Neutrophils; D011655:Pulmonary Embolism / Q000097:blood / Q000401:mortality / Q000503:physiopathology; D012189:Retrospective Studies; D015996:Survival Rate
keywords: Lymphocytes; Pulmonary embolism; White blood cells