title: The impact of beta-blocker therapy on anemia after traumatic brain injury.
abstract: BACKGROUND
  An increase in endogenous catecholamine levels after traumatic brain injury (TBI) is well described. Animal studies suggest that postinjury anemia is exacerbated by a persistent hyperadrenergic state. This study aims to determine if beta-blocker (BB) exposure affects anemia after TBI.
  
  
  METHODS
  We reviewed a Level I trauma registry for patients with TBI, examining markers of anemia between patients who received BB with those who did not.
  
  
  RESULTS
  A total of 174 patients were exposed to BB (BB+) and 245 were not exposed (BB-). The mean age in the BB+ group was 50 years (vs. 36 years in BB- group, p < 0.001). The mean injury severity score was 33.6 for the BB+ group (vs. 30.8 for BB- group, p = 0.01). While BB+ patients were more likely to receive a transfusion (60.9% vs. 35.1%, p < 0.001), BB+ patients reached their nadir hemoglobin (Hb) at a later day of hospitalization and their rate of decrease in Hb was significantly slower (both p < 0.001). Choosing Hb cutoffs for anemia of both 7 and 10 g/dL, Kaplan-Meier demonstrated a significant delay in time to anemia.
  
  
  CONCLUSIONS
  This study suggests beta-blockade delays anemia after TBI. Elaboration of this effect may demonstrate an additional benefit of beta-blockade after head injury.
authors.affiliation: Department of Surgery, New York University School of Medicine, New York, New York, USA.
authors.forename: Nina E
authors.initials: NE
authors.lastname: Glass
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Kaltenbach
authors.forename: Sloan B
authors.initials: SB
authors.lastname: Fleming
authors.forename: Patrick G
authors.initials: PG
authors.lastname: Arbogast
authors.forename: Bryan A
authors.initials: BA
authors.lastname: Cotton
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D000740:Anemia / Q000209:etiology / Q000517:prevention & control*; D001803:Blood Transfusion / Q000706:statistics & numerical data; D001930:Brain Injuries / Q000097:blood* / Q000188:drug therapy; D002395:Catecholamines / Q000097:blood*; D004341:Drug Evaluation; D017707:Erythrocyte Transfusion / Q000706:statistics & numerical data; D005260:Female; D015600:Glasgow Coma Scale; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D012042:Registries; D012189:Retrospective Studies; D015599:Trauma Severity Indices; D055815:Young Adult
chemical_list: D000319:Adrenergic beta-Antagonists; D002395:Catecholamines; D006454:Hemoglobins