title: Frailty Before Critical Illness and Mortality for Elderly Medicare Beneficiaries.
abstract: OBJECTIVE
  To estimate the effect of pre-intensive care unit (ICU) health categories on mortality during and after critical illness, focusing specifically on the effect of pre-ICU frailty on short- and long-term mortality.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Medicare claims data from 2004 to 2008.
  
  
  METHODS
  A nationally representative sample of elderly Medicare beneficiaries admitted to an ICU in 2005.
  
  
  METHODS
  Participants were classified into four pre-ICU health categories (robust, cancer, chronic organ failure, frailty) using claims data from the year before admission, allowing for assignment to multiple categories. The association between pre-ICU health category and hospital and 3-year mortality was assessed using multivariable logistic regression and Cox proportional hazards models.
  
  
  RESULTS
  Of 47,427 elderly individuals in the ICU, 18.8% were robust, 28.6% had cancer, 68.1% had chronic organ failure, and 34.0% were frail; 41.3% qualified for multiple categories. Overall hospital mortality was 12.6%, with the lowest mortality for robust participants (9.7%). Participants with pre-ICU frailty had higher hospital mortality than those with the same pre-ICU health categories without frailty. (Adjusted odds ratios ranged from 1.27 (95% confidence interval (CI) 1.10-1.47) to 1.52 (95% CI = 1.35-1.63).) Robust hospital survivors had the lowest 3-year mortality (24.6%). Pre-ICU frailty conferred higher 3-year mortality than pre-ICU categories without frailty. (Adjusted hazard ratios ranged from 1.54 (95% CI = 1.45-1.64) to 1.84 (95% CI = 1.70-1.99).)
  
  
  CONCLUSIONS
  Critically ill elderly adults can be categorized according to pre-ICU health categories. These categories, particularly pre-ICU frailty, may be important for understanding risk of death during and after critical illness.
authors.affiliation: Division of Critical Care Medicine, Department of Medicine, Albert Einstein College of Medicine, Bronx, New York.
authors.forename: Aluko A
authors.initials: AA
authors.lastname: Hope
authors.affiliation: Division of Critical Care Medicine, Department of Medicine, Albert Einstein College of Medicine, Bronx, New York.|Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, New York.
authors.forename: Michelle N
authors.initials: MN
authors.lastname: Gong
authors.affiliation: Division of Critical Care, Department of Anesthesiology, College of Physicians and Surgeons, Columbia University, New York, New York.
authors.forename: Carmen
authors.initials: C
authors.lastname: Guerra
authors.affiliation: Division of Critical Care, Department of Anesthesiology, College of Physicians and Surgeons, Columbia University, New York, New York.|Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York.
authors.forename: Hannah
authors.initials: H
authors.lastname: Wunsch
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016638:Critical Illness / Q000401:mortality*; D005260:Female; D016330:Frail Elderly / Q000706:statistics & numerical data*; D015577:Geriatric Assessment / Q000706:statistics & numerical data*; D017052:Hospital Mortality / Q000639:trends*; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007362:Intensive Care Units; D016015:Logistic Models; D008297:Male; D006278:Medicare / Q000706:statistics & numerical data*; D012307:Risk Factors; D017741:Survivors / Q000706:statistics & numerical data; D014481:United States / Q000453:epidemiology
keywords: Medicare; aged; critical illness; frailty; prognosis