title: High levels of comorbidity and disability cancel out the dementia effect in predictions of long-term mortality after discharge in the very old.
abstract: OBJECTIVE
  The relative weight of various etiologies of dementia as predictors of long-term mortality after other risk factors have been taken into account remains unclear. We investigated the 5-year mortality risk associated with dementia in elderly people after discharge from acute care, taking into account comorbid conditions and functionality.
  
  
  METHODS
  A prospective cohort study of 444 patients (mean age: 85 years; 74% female) discharged from the acute geriatric unit of Geneva University Hospitals. On admission, each subject underwent a standardized diagnostic evaluation: demographic variables, cognitive, comorbid medical conditions and functional assessment. Patients were followed yearly by the same team. Predictors of survival at 5 years were evaluated by Cox proportional hazards models.
  
  
  RESULTS
  The univariate model showed that being older and male, and having vascular and severe dementia, comorbidity and functional disability, were predictive of shorter survival. However, in the full multivariate model adjusted for age and sex, the effect of dementia type or severity completely disappeared when all the variables were added. In multivariate analysis, the best predictor was higher comorbidity score, followed by functional status (R(2) = 23%).
  
  
  CONCLUSIONS
  The identification of comorbidity and functional impairment effects as predictive factors for long-term mortality independent of cognitive status may increase the accuracy of long-term discharge planning.
authors.affiliation: Rehabilitation and Geriatrics Department, Geneva University, Thônex, Switzerland. dina.zekry @ hcuge.ch
authors.forename: Dina
authors.initials: D
authors.lastname: Zekry
authors.forename: François R
authors.initials: FR
authors.lastname: Herrmann
authors.forename: Christophe E
authors.initials: CE
authors.lastname: Graf
authors.forename: Sandra
authors.initials: S
authors.lastname: Giannelli
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Michel
authors.forename: Gabriel
authors.initials: G
authors.lastname: Gold
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Krause
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D003072:Cognition Disorders / Q000145:classification / Q000150:complications*; D015331:Cohort Studies; D015897:Comorbidity; D003704:Dementia / Q000145:classification / Q000401:mortality*; D004185:Disability Evaluation; D005260:Female; D005500:Follow-Up Studies; D015577:Geriatric Assessment; D006801:Humans; D008297:Male; D017063:Outcome Assessment, Health Care; D010351:Patient Discharge; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D016019:Survival Analysis