title: Association between an increase in blood urea nitrogen at 24 hours and worse outcomes in acute nonvariceal upper GI bleeding.
abstract: OBJECTIVE
  An increase in blood urea nitrogen (BUN) at 24 hours is a solitary and significant predictor of mortality in patients with acute pancreatitis, which may predict worse outcomes in the similarly resuscitation-requiring condition of acute nonvariceal upper GI bleeding (UGIB). The aim of our study was to assess whether an increase in BUN at 24 hours is predictive of worse clinical outcomes in acute nonvariceal UGIB.
  
  
  METHODS
  A retrospective cohort study including patients admitted to an academic hospital from 2004 to 2014 was conducted. An increase in BUN was defined as an increase in BUN at 24 hours of hospitalization compared with BUN at presentation. The primary outcome was a composite of inpatient death, inpatient rebleeding, need for surgical or radiologic intervention, or endoscopic reintervention. Associations between BUN change and outcomes were assessed via the Pearson χ2test and the Fisher exact test and via logistic regression for adjusted analyses.
  
  
  RESULTS
  There were 357 patients included in the analysis with a mean age of 64 years; 54% were men. The mean change in BUN was -10.1 mg/dL (standard deviation, 12.7 mg/dL). Patients with an increased BUN (n = 37 [10%]) were significantly more likely to experience the composite outcome (22% vs 9%, P = .014), including an increased risk of inpatient death (8% vs 1%, P = .004), compared with patients with a decreased or unchanged BUN (n = 320 [90%]). In a logistic regression model adjusting for the AIMS65 score, an increase in BUN was independently associated with an increased risk for the composite outcome (odds ratio, 2.75; P = .026).
  
  
  CONCLUSIONS
  Increasing BUN at 24 hours likely reflects under resuscitation and is a predictor of worse outcomes in patients with acute nonvariceal UGIB.
authors.affiliation: Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women's Hospital, Boston, Massachusetts, USA; Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Navin L
authors.initials: NL
authors.lastname: Kumar
authors.affiliation: Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Brian L
authors.initials: BL
authors.lastname: Claggett
authors.affiliation: Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Aaron J
authors.initials: AJ
authors.lastname: Cohen
authors.affiliation: Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women's Hospital, Boston, Massachusetts, USA; Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Nayor
authors.affiliation: Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women's Hospital, Boston, Massachusetts, USA; Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: John R
authors.initials: JR
authors.lastname: Saltzman
mesh_terms: D000208:Acute Disease; D000368:Aged; D019540:Area Under Curve; D001806:Blood Urea Nitrogen; D004378:Duodenal Diseases / Q000097:blood* / Q000628:therapy; D016099:Endoscopy, Gastrointestinal; D004935:Esophageal Diseases / Q000097:blood* / Q000628:therapy; D005260:Female; D006471:Gastrointestinal Hemorrhage / Q000097:blood* / Q000601:surgery; D016558:Hemostasis, Endoscopic; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D012372:ROC Curve; D015642:Radiology, Interventional; D012008:Recurrence; D019233:Retreatment; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods; D013272:Stomach Diseases / Q000097:blood* / Q000628:therapy; D013997:Time Factors