Journal of General Internal Medicine

, Volume 13, Issue 4, pp 234–242 | Cite as

Does delirium contribute to poor hospital outcomes?

A three-site epidemiologic study
  • Sharon K. Inouye
  • Julia T. Rushing
  • Marquis D. Foreman
  • Robert M. Palmer
  • Peter Pompei
Original Articles


OBJECTIVE: To determine the independent contribution of admission delirium to hospital outcomes including mortality, institutionalization, and functional decline.

DESIGN: Three prospective cohort studies.

SETTING: Three university-affiliated teaching hospitals.

PATIENTS: Consecutive samples of 727 patients, aged 65 years and older.

MEASUREMENTS AND MAIN RESULTS: Delirum was present at admission in 88 (12%) of 727 patients. The main outcome measures at hospital discharge and 3-month follow-up were death, new nursing home placement, death or new nursing home placement, and functional decline. At hospital discharge, new nursing home placement occurred in 60 (9%) of 692 patients, and the adjusted odds ratio (OR) for delirium, controlling for baseline covariates of age, gender, dementia, APACHE II score, and functional measures, was 3.0, (95% confidence interval [CI] 1.4, 6.2). Death or new nursing home placement occurred in 95 (13%) of 727 patients (adjusted OR for delirium 2.1, 95% CI 1.1, 4.0). The findings were replicated across all sites. The associations between delirium and death alone (in 35 [5%] of 727 patients) and between delirium and length of stay were not statistically significant. At 3-month follow-up, new nursing home placement occurred in 77 (13%) of 600 patients (adjusted OR for delirium 3.0; 95% CI 1.5, 6.0). Death or new nursing home placement occurred in 165 (25%) of 663 patients (adjusted OR for delirium 2.6; 95% CI 1.4, 4.5). The findings were replicated across all sites. For death alone (in 98 [14%] of 680 patients), the adjusted OR for delirium was 1.6 (95% CI 0.8, 3.2). Delirium was a significant predictor of functional decline at both hospital discharge (adjusted OR 3.0; 95% CI 1.6, 5.8) and follow-up (adjusted OR 2.7; 95% CI 1.4, 5.2).

CONCLUSIONS: Delirium is an important independent prognostic determinant of hospital outcomes including new nursing home placement, death or new nursing home placement, and functional decline—even after controlling for age, gender, dementia, illness severity, and functional status. Thus, delirium should be considered as a prognostic variable in case-mix adjustment systems and in studies examining hospital outcomes in older persons.

Key words

delirium acute confusional state risk adjustment geriatrics hospital outcomes 


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Copyright information

© Society of General Internal Medicine 1998

Authors and Affiliations

  • Sharon K. Inouye
    • 1
  • Julia T. Rushing
    • 2
  • Marquis D. Foreman
    • 3
  • Robert M. Palmer
    • 5
  • Peter Pompei
    • 4
  1. 1.Received from the Department of Internal MedicineYale University School of MedicineNew Haven
  2. 2.Department of Public Health SciencesBowman Gray School of Medicine of Wake Forest UniversityWinston-Salem
  3. 3.Department of NursingUniversity of Chicago Hospitals
  4. 4.Department of MedicineUniversity of Chicago Hospitals
  5. 5.the Department of MedicineUniversity Hospitals of Cleveland

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