title: Five-Year Mortality and Hospital Costs Associated with Surviving Intensive Care.
abstract: Survivors of critical illness experience significant morbidity, but the impact of surviving the intensive care unit (ICU) has not been quantified comprehensively at a population level.
  
  
  
  To identify factors associated with increased hospital resource use and to ascertain whether ICU admission was associated with increased mortality and resource use.
  
  
  
  Matched cohort study and pre/post-analysis using national linked data registries with complete population coverage. The population consisted of patients admitted to all adult general ICUs during 2005 and surviving to hospital discharge, identified from the Scottish Intensive Care Society Audit Group registry, matched (1:1) with similar hospital control subjects. Five-year outcomes included mortality and hospital resource use. Confounder adjustment was based on multivariable regression and pre/post within-individual analyses.
  
  
  
  Of 7,656 ICU patients, 5,259 survived to hospital discharge (5,215 [99.2%] matched to hospital control subjects). Factors present before ICU admission (comorbidities/pre-ICU hospitalizations) were stronger predictors of hospital resource use than acute illness factors. In the 5 years after the initial hospital discharge, compared with hospital control subjects, the ICU cohort had higher mortality (32.3% vs. 22.7%; hazard ratio, 1.33; 95% confidence interval, 1.22-1.46; P < 0.001), used more hospital resources (mean hospital admission rate, 4.8 vs. 3.3/person/5 yr), and had 51% higher mean 5-year hospital costs ($25,608 vs. $16,913/patient). Increased resource use persisted after confounder adjustment (P < 0.001) and using pre/post-analyses (P < 0.001). Excess resource use and mortality were greatest for younger patients without significant comorbidity.
  
  
  
  This complete, national study demonstrates that ICU survivorship is associated with higher 5-year mortality and hospital resource use than hospital control subjects, representing a substantial burden on individuals, caregivers, and society.
authors.affiliation: 1 Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, United Kingdom.|2 Department of Anaesthesia, Critical Care and Pain, University of Edinburgh, Royal Infirmary of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Nazir I
authors.initials: NI
authors.lastname: Lone
authors.affiliation: 2 Department of Anaesthesia, Critical Care and Pain, University of Edinburgh, Royal Infirmary of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Gillies
authors.affiliation: 3 Information Services Division, NHS Scotland, Edinburgh, United Kingdom; and.
authors.forename: Catriona
authors.initials: C
authors.lastname: Haddow
authors.affiliation: 3 Information Services Division, NHS Scotland, Edinburgh, United Kingdom; and.
authors.forename: Richard
authors.initials: R
authors.lastname: Dobbie
authors.affiliation: 4 Intensive Care National Audit & Research Centre, London, United Kingdom.
authors.forename: Kathryn M
authors.initials: KM
authors.lastname: Rowan
authors.affiliation: 1 Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Sarah H
authors.initials: SH
authors.lastname: Wild
authors.affiliation: 1 Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Gordon D
authors.initials: GD
authors.lastname: Murray
authors.affiliation: 2 Department of Anaesthesia, Critical Care and Pain, University of Edinburgh, Royal Infirmary of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Timothy S
authors.initials: TS
authors.lastname: Walsh
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D003422:Critical Care / Q000191:economics* / Q000706:statistics & numerical data*; D016638:Critical Illness / Q000191:economics* / Q000401:mortality*; D005260:Female; D017721:Hospital Costs / Q000706:statistics & numerical data*; D006801:Humans; D007362:Intensive Care Units / Q000191:economics / Q000706:statistics & numerical data; D007902:Length of Stay / Q000191:economics / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012042:Registries; D012606:Scotland / Q000453:epidemiology; D012737:Sex Factors; D017741:Survivors / Q000706:statistics & numerical data
keywords: hospital costs; hospital readmission; intensive care; mortality; registries
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