title: Postoperative day one neutrophil-to-lymphocyte ratio as a predictor of 30-day outcomes in bariatric surgery patients.
abstract: The neutrophil-to-lymphocyte ratio (NLR) is a marker that reflects systemic inflammation and organ dysfunction. Its use as a prognostic marker to predict complications following surgery has been recently described in the literature.
  
  
  
  The objective of our study was to evaluate the use of postoperative day one (POD1) NLR as a predictor of 30-day outcomes in patients undergoing bariatric surgery.
  
  
  
  University Hospital.
  
  
  
  We performed a retrospective chart review of 789 patients who underwent bariatric surgery at our institution between March 2012 and May 2014. Data were collected from electronic patient records and administrative databases used for quality improvement. POD1 NLR values were obtained from complete blood counts along with a variety of 30-day clinical outcomes. Univariate and multivariable analyses were conducted to determine whether POD1 NLR ≥10 was associated with 30-day outcomes.
  
  
  
  Seven-hundred and thirty-seven patients were included in the study. Six-hundred and fifty-three Roux-en-Y gastric bypass surgeries (88.6 %) and 84 sleeve gastrectomy surgeries (11.4 %) were performed. All surgeries were performed laparoscopically. We observed a 4.7 % readmission rate, 2.2 % reoperation rate, 10.7 % postoperative occurrence rate, and 0.1 % mortality rate. After covariate adjustment, POD1 NLR ≥10 was found to be significantly associated with overall complications (OR 1.98, 95 % CI 1.01-3.87), major complications (OR 3.71, 95 % CI 1.76-7.82), reoperation (OR 3.63, 95 % CI 1.14-11.6), and prolonged postoperative length of stay (OR 3.70, 95 % CI 2.2-6.22).
  
  
  
  POD1 NLR was independently associated with 30-day outcomes following bariatric surgery. This easily obtained inflammatory marker may be used to help identify patients at a higher risk of developing early complications.
authors.affiliation: Department of Medicine, University of Toronto, Toronto, ON, Canada.
authors.forename: Matthew
authors.initials: M
authors.lastname: Da Silva
authors.affiliation: Division of General Surgery, Toronto Western Hospital, University Health Network, 399 Bathurst Street, Toronto, ON, M5T 2S8, Canada.
authors.forename: Michelle C
authors.initials: MC
authors.lastname: Cleghorn
authors.affiliation: Division of General Surgery, Toronto Western Hospital, University Health Network, 399 Bathurst Street, Toronto, ON, M5T 2S8, Canada.|Department of Surgery, University of Toronto, Toronto, ON, Canada.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Elnahas
authors.affiliation: Division of General Surgery, Toronto Western Hospital, University Health Network, 399 Bathurst Street, Toronto, ON, M5T 2S8, Canada.|Department of Surgery, University of Toronto, Toronto, ON, Canada.
authors.forename: Timothy D
authors.initials: TD
authors.lastname: Jackson
authors.affiliation: Division of General Surgery, Toronto Western Hospital, University Health Network, 399 Bathurst Street, Toronto, ON, M5T 2S8, Canada.|Department of Surgery, University of Toronto, Toronto, ON, Canada.
authors.forename: Allan
authors.initials: A
authors.lastname: Okrainec
authors.affiliation: Division of General Surgery, Toronto Western Hospital, University Health Network, 399 Bathurst Street, Toronto, ON, M5T 2S8, Canada. fayez.quereshy@uhn.ca.|Department of Surgery, University of Toronto, Toronto, ON, Canada. fayez.quereshy@uhn.ca.
authors.forename: Fayez A
authors.initials: FA
authors.lastname: Quereshy
mesh_terms: D000328:Adult; D000368:Aged; D050110:Bariatric Surgery; D005260:Female; D005743:Gastrectomy; D015390:Gastric Bypass; D006801:Humans; D007249:Inflammation; D010535:Laparoscopy; D007902:Length of Stay / Q000706:statistics & numerical data*; D007958:Leukocyte Count; D018655:Lymphocyte Count; D008214:Lymphocytes / Q000166:cytology*; D008297:Male; D008875:Middle Aged; D009026:Mortality; D009504:Neutrophils / Q000166:cytology*; D009767:Obesity, Morbid / Q000601:surgery*; D009864:Ontario / Q000453:epidemiology; D010359:Patient Readmission / Q000706:statistics & numerical data*; D011183:Postoperative Complications / Q000097:blood / Q000453:epidemiology*; D011184:Postoperative Period; D011379:Prognosis; D012086:Reoperation / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D055815:Young Adult
keywords: Bariatric; Complications; Inflammatory marker; Neutrophil-to-lymphocyte ratio (NLR); Postoperative