title: Health care-associated methicillin-resistant Staphylococcus aureus infections increases the risk of postdischarge mortality.
abstract: BACKGROUND
  Although many studies have estimated the impact of health care-associated methicillin-resistant Staphylococcus aureus (MRSA) infections on mortality during initial hospitalization, little is known about the long-term risk of death in these patients. The purpose of this study was to quantify the effect of MRSA health care-acquired infections (HAIs) on mortality after hospital discharge.
  
  
  METHODS
  Our study cohort consisted of patients with inpatient admission within the U.S. Department of Veterans Affairs system between October 1, 2007, and September 30, 2010. Of these patients, we identified those with a positive MRSA culture from electronic microbiology reports. We constructed multivariable Cox proportional hazards regressions to assess the impact of a positive culture on postdischarge mortality in the 365 days following discharge using both the full cohort and a propensity score-matched subsample.
  
  
  RESULTS
  In our analysis cohort of 369,743 inpatients, positive MRSA cultures were recorded in 3,599 (1.0%) patients. We found that positive cultures resulted in an increased risk of postdischarge mortality both in the full cohort (hazard ratio = 1.42, P < .001) and in the subset of propensity score-matched patients (hazard ratio = 1.37, P < .0001).
  
  
  CONCLUSIONS
  We found that MRSA HAIs significantly elevate the long-term risk of mortality. These results underscore the importance of infection prevention efforts in the hospital.
authors.affiliation: IDEAS Center, Veterans Affairs Salt Lake City Health System, Salt Lake City, UT; Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT. Electronic address: richard.nelson@utah.edu.
authors.forename: Richard E
authors.initials: RE
authors.lastname: Nelson
authors.affiliation: IDEAS Center, Veterans Affairs Salt Lake City Health System, Salt Lake City, UT; Department of Pharmacotherapy, Pharmacotherapy Outcomes Research Center, University of Utah College of Pharmacy, Salt Lake City, UT.
authors.forename: Vanessa W
authors.initials: VW
authors.lastname: Stevens
authors.affiliation: IDEAS Center, Veterans Affairs Salt Lake City Health System, Salt Lake City, UT; Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT.
authors.forename: Makoto
authors.initials: M
authors.lastname: Jones
authors.affiliation: IDEAS Center, Veterans Affairs Salt Lake City Health System, Salt Lake City, UT; Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT.
authors.forename: Matthew H
authors.initials: MH
authors.lastname: Samore
authors.affiliation: IDEAS Center, Veterans Affairs Salt Lake City Health System, Salt Lake City, UT; Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Rubin
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology* / Q000401:mortality*; D005260:Female; D006761:Hospitals; D006801:Humans; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000302:isolation & purification*; D008875:Middle Aged; D010351:Patient Discharge; D012189:Retrospective Studies; D013203:Staphylococcal Infections / Q000453:epidemiology / Q000382:microbiology* / Q000401:mortality*; D016019:Survival Analysis; D014481:United States / Q000453:epidemiology
keywords: Health care–associated infection; Methicillin-resistant Staphylococcus aureus; Mortality; Veterans affairs