title: Risk factors and mortality for nosocomial bloodstream infections in elderly patients.
abstract: OBJECTIVE
  To determine risk factors for nosocomial bloodstream infection (BSI) and associated mortality in geriatric patients in geriatric and internal medicine wards at a university hospital.
  
  
  METHODS
  Single-center retrospective (1992-2007), pairwise-matched (1:1-ratio) cohort study. Geriatric patients with nosocomial BSI were matched with controls without BSI on year of admission and length of hospitalization before onset of BSI. Demographic, microbiological, and clinical data are collected.
  
  
  RESULTS
  One-hundred forty-two BSI occurred in 129 patients. Predominant microorganisms were Escherichia coli (23.2%), coagulase-negative Staphylococci (19.4%), Pseudomonas aeruginosa (8.4%), Staphylococcus aureus (7.1%), Klebsiella pneumoniae (5.8%) and Candida spp. (5.8%). Matching was successful for 109 cases. Compared to matched control subjects, cases were more frequently female, suffered more frequently from arthrosis, angina pectoris and pressure ulcers, had worse Activities of Daily Living-scores, had more often an intravenous or bladder catheter, and were more often bedridden. Logistic regression demonstrated presence of an intravenous catheter (odds ratio [OR] 7.5, 95% confidence interval [CI] 2.5-22.9) and being bedridden (OR 2.9, 95% CI 1.6-5.3) as independent risk factors for BSI. In univariate analysis nosocomial BSI was associated with increased mortality (22.0% vs. 11.0%; P=0.029). After adjustment for confounding co-variates, however, nosocomial BSI was not associated with mortality (hazard ratio 1.3, 95% CI 0.6-2.6). Being bedridden and increasing age were independent risk factors for death.
  
  
  CONCLUSIONS
  Intravenous catheters and being bedridden are the main risk factors for nosocomial BSI. Although associated with higher mortality, this infectious complication seems not to be an independent risk factor for death in geriatric patients.
authors.affiliation: Faculty of Medicine and Health Sciences, Ghent University, Belgium.
authors.forename: S
authors.initials: S
authors.lastname: Reunes
authors.forename: V
authors.initials: V
authors.lastname: Rombaut
authors.forename: D
authors.initials: D
authors.lastname: Vogelaers
authors.forename: N
authors.initials: N
authors.lastname: Brusselaers
authors.forename: C
authors.initials: C
authors.lastname: Lizy
authors.forename: M
authors.initials: M
authors.lastname: Cankurtaran
authors.forename: S
authors.initials: S
authors.lastname: Labeau
authors.forename: M
authors.initials: M
authors.lastname: Petrovic
authors.forename: S
authors.initials: S
authors.lastname: Blot
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D016470:Bacteremia / Q000453:epidemiology* / Q000209:etiology / Q000382:microbiology; D001419:Bacteria / Q000302:isolation & purification*; D001530:Belgium / Q000453:epidemiology; D002406:Catheterization, Peripheral / Q000009:adverse effects*; D057785:Catheters / Q000382:microbiology*; D003428:Cross Infection / Q000453:epidemiology* / Q000209:etiology / Q000382:microbiology; D005260:Female; D005500:Follow-Up Studies; D015577:Geriatric Assessment / Q000379:methods*; D006801:Humans; D015994:Incidence; D008297:Male; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends