title: Effect of beta-blocker therapy on the risk of infections and death after acute stroke--a historical cohort study.
abstract: BACKGROUND
  Infections are a frequent cause for prolonged hospitalization and increased mortality after stroke. Recent studies revealed a stroke-induced depression of the peripheral immune system associated with an increased susceptibility for infections. In a mice model for stroke, this immunosuppressive effect was reversible after beta-blocker administration. The aim of our study was to investigate the effect of beta-blocker therapy on the risk of infections and death after stroke in humans.
  
  
  METHODS
  625 consecutive patients with ischemic or hemorrhagic stroke, admitted to a university hospital stroke unit, were included in this historical cohort study. The effect of beta-blocker therapy on post-stroke pneumonia, urinary tract infections and death was investigated using multivariable Poisson and Cox regression models.
  
  
  RESULTS
  553 (88.3%) patients were admitted with ischemic stroke, the remaining 72 (11.7%) had a hemorrhagic stroke. Median baseline NIHSS was 8 (IQR 5-16) points. 301 (48.2%) patients received beta-blocker therapy. There was no difference in the risk of post-stroke pneumonia between patients with and without beta-blocker therapy (Rate Ratio = 1.00, 95%CI 0.77-1.30, p = 0.995). Patients with beta-blocker therapy showed a decreased risk for urinary tract infections (RR = 0.65, 95%CI 0.43-0.98, p = 0.040). 7-days mortality did not differ between groups (Hazard Ratio = 1.36, 95%CI 0.65-2.77, p = 0.425), while patients with beta-blocker therapy showed a higher 30-days mortality (HR = 1.93, 95%CI 1.20-3.10, p = 0.006).
  
  
  CONCLUSIONS
  Beta-blocker therapy did not reduce the risk for post-stroke pneumonia, but significantly reduced the risk for urinary tract infections. Different immune mechanisms underlying both diseases might explain these findings that need to be confirmed in future studies.
authors: Department of Neurology, University Medicine Göttingen, Göttingen, Germany.
authors: Ilko L
authors: IL
authors: Maier
authors: Research group Epidemiological and Statistical Methods (ESME), Department of Epidemiology, Helmholtz Centre for Infection Research, Braunschweig, Germany; German Center for Infection Research (DZIF), Braunschweig site, Braunschweig, Germany.
authors: André
authors: A
authors: Karch
authors: Research group Epidemiological and Statistical Methods (ESME), Department of Epidemiology, Helmholtz Centre for Infection Research, Braunschweig, Germany; German Center for Infection Research (DZIF), Braunschweig site, Braunschweig, Germany; Hannover Medical School, Hannover, Germany.
authors: Rafael
authors: R
authors: Mikolajczyk
authors: Department of Neurology, University Medicine Göttingen, Göttingen, Germany.
authors: Mathias
authors: M
authors: Bähr
authors: Department of Neurology, University Medicine Göttingen, Göttingen, Germany.
authors: Jan
authors: J
authors: Liman
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000494:pharmacology* / Q000627:therapeutic use; D000368:Aged; D015331:Cohort Studies; D005260:Female; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D007239:Infections / Q000150:complications* / Q000188:drug therapy / Q000276:immunology; D008297:Male; D020521:Stroke / Q000150:complications* / Q000188:drug therapy / Q000401:mortality*; D016896:Treatment Outcome
chemical_list: D000319:Adrenergic beta-Antagonists; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors
references: J Neuroimmunol. 1994 Dec;55(2):195-203
references: 7530260
references: J Immunol. 1998 Nov 15;161(10):5124-8
references: 9820479
references: J Atheroscler Thromb. 2004;11(5):253-64
references: 15557707
references: J Cereb Blood Flow Metab. 2006 May;26(5):654-65
references: 16121126
references: Neurology. 2006 May 9;66(9):1325-9
references: 16525122
references: Nat Clin Pract Neurol. 2005 Dec;1(2):106-12
references: 16932506
references: J Neurol Sci. 2007 Jan 15;252(1):53-6
references: 17134722
references: Trends Immunol. 2007 Jan;28(1):12-8
references: 17129764
references: Neurology. 2007 Feb 13;68(7):509-14
references: 17296916
references: Stroke. 2007 Mar;38(3):1097-103
references: 17255542
references: Lancet Infect Dis. 2007 May;7(5):358-68
references: 17448939
references: J Burn Care Res. 2009 Jan-Feb;30(1):8-18
references: 19060758
references: Neuroscience. 2009 Feb 6;158(3):1184-93
references: 18722511
references: Curr Med Chem. 2009;16(9):1082-90
references: 19275613
references: Crit Care Med. 2010 Feb;38(2):388-94
references: 19829100
references: J Clin Neurosci. 2010 Feb;17(2):187-90
references: 20006511
references: Nat Rev Immunol. 2010 Dec;10(12):826-37
references: 21088683
references: Nat Med. 2011 Jul;17(7):796-808
references: 21738161
references: Epidemiology. 2011 Sep;22(5):745
references: 21811114
references: Neurology. 2011 Sep 6;77(10):965-72
references: 21865573
references: Neurology. 2011 Oct 4;77(14):1338-45
references: 21940613
references: BMC Neurol. 2011;11:110
references: 21933425
references: Science. 2011 Oct 7;334(6052):101-5
references: 21921158
references: Cerebrovasc Dis. 2011;32(6):552-60
references: 22104620
references: Nat Rev Neurol. 2012 Jul;8(7):401-10
references: 22664787
references: Crit Care Med. 2012 Oct;40(10):2768-72
references: 22824934
references: Neurobiol Dis. 2014 Feb;62:456-68
references: 24184800
references: J Neuroimmunol. 2000 Jun 1;105(1):31-8
references: 10713361
references: Nat Immunol. 2004 Jun;5(6):575-81
references: 15164017
references: Atherosclerosis. 2004 Jul;175(1):83-90
references: 15186950
references: Br Med J (Clin Res Ed). 1988 Mar 12;296(6624):737-41
references: 3126956