title: Neutrophil-lymphocyte ratio as a predictor of cognitive dysfunction in carotid endarterectomy patients.
abstract: BACKGROUND
  Systemic inflammation has been implicated in the development of cognitive dysfunction following carotid endarterectomy (CEA). Neutrophil-lymphocyte ratio (NLR) is a reliable measure of systemic inflammation. We hypothesize that patients with elevated preoperative NLR have increased risk of cognitive dysfunction 1 day after CEA.
  
  
  METHODS
  Five hundred fifty-one patients scheduled for CEA were enrolled at Columbia University in New York, NY from 1995 to 2012. NLR was retrospectively reviewed; only 432 patients had preoperative NLR values available within 2 weeks of CEA. NLR was analyzed as a continuous variable and categorically with a cutoff of ≥5 and <5 and equal tertiles, as done in previous studies.
  
  
  RESULTS
  Patients with cognitive dysfunction had significantly higher NLR than those without cognitive dysfunction (4.5 ± 4.0 vs 3.2 ± 2.6; P < .001). The incidence of cognitive dysfunction was significantly higher in patients with NLR ≥5 than NLR <5 (34.7% vs 12.8%; P < .001). Significantly fewer patients in the low tertile had cognitive dysfunction than in the high tertile (6.9% vs 25.9%; P <.001) and middle tertile (6.9% vs 17.4%; P = .006). In the final multivariate model, diabetes mellitus (odds ratio [OR], 2.03; 95% confidence interval [CI], 1.08-3.75; P = .03) and NLR ≥5 (OR, 3.38; 95% CI, 1.81-6.27; P < .001) were significantly associated with higher odds of cognitive dysfunction, while statin use was significantly associated with lower odds (OR, 0.48; 95% CI, 0.27-0.84; P = .01).
  
  
  CONCLUSIONS
  Preoperative NLR is associated with cognitive dysfunction 1 day after CEA. NLR ≥5 and diabetes mellitus are significantly associated with increased odds of cognitive dysfunction whereas statin use is significantly associated with decreased odds.
authors.affiliation: Department of Medicine, Columbia University, New York, NY.
authors.forename: Hadi J
authors.initials: HJ
authors.lastname: Halazun
authors.affiliation: Department of Anesthesiology, Columbia University, New York, NY.
authors.forename: Joanna L
authors.initials: JL
authors.lastname: Mergeche
authors.affiliation: Department of Anesthesiology, Columbia University, New York, NY.
authors.forename: Kaitlin A
authors.initials: KA
authors.lastname: Mallon
authors.affiliation: Department of Neurology, Columbia University, New York, NY; Department of Neurological Surgery, Columbia University, New York, NY.
authors.forename: E Sander
authors.initials: ES
authors.lastname: Connolly
authors.affiliation: Department of Anesthesiology, Columbia University, New York, NY; Department of Neurology, Columbia University, New York, NY. Electronic address: ejh3@cumc.columbia.edu.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Heyer
mesh_terms: D000368:Aged; D002340:Carotid Artery Diseases / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology / Q000276:immunology / Q000601:surgery*; D016009:Chi-Square Distribution; D003071:Cognition; D003072:Cognition Disorders / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology* / Q000276:immunology / Q000523:psychology; D015897:Comorbidity; D003920:Diabetes Mellitus / Q000453:epidemiology; D016894:Endarterectomy, Carotid / Q000009:adverse effects*; D005260:Female; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use; D015994:Incidence; D016015:Logistic Models; D018655:Lymphocyte Count; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D015999:Multivariate Analysis; D009504:Neutrophils / Q000276:immunology*; D009519:New York City / Q000453:epidemiology; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors