title: Risk factors for delirium in hospitalized elderly.
abstract: OBJECTIVE
  To determine risk factors for delirium in elderly hospitalized patients.
  
  
  METHODS
  Cohort analytic study. Using a reliable and valid instrument for detection of delirium, we prospectively followed up a cohort of elderly patients admitted to an acute care hospital. Using standardized criteria, we collected risk factor data from patient medical records.
  
  
  METHODS
  General medical and surgical wards of a tertiary-care hospital.
  
  
  METHODS
  Patients (n = 325) were 65 years of age or older, from either a geographically defined community or a long-term-care institution. We studied those patients (n = 291) not delirious on first evaluation. Fifty-seven patients or their families refused participation.
  
  
  METHODS
  Incidence of delirium and risk factors calculated as adjusted odds ratios (ORs).
  
  
  RESULTS
  Delirium developed in 91 patients. By stepwise logistic regression, the independent risk factors for in-hospital delirium included prior cognitive impairment (OR, 8.97; 95% confidence interval [CI], 3.99 to 20.14), age over 80 years (OR, 5.22; 95% CI, 2.60 to 10.46), fracture on admission (OR, 6.57; 95% CI, 2.23 to 19.33), symptomatic infection (OR, 2.96; 95% CI, 1.42 to 6.15), and male sex (OR, 2.40; 95% CI, 1.19 to 4.84). Among medication groups, only neuroleptic use (OR, 4.48; 95% CI, 1.82 to 10.45) and narcotic use (OR, 2.54; 95% CI, 1.24 to 5.18) were independently associated with delirium. Anticholinergic use was not associated with delirium.
  
  
  CONCLUSIONS
  Delirium in hospitalized patients is most closely associated with factors already present on admission such as prior cognitive impairment, advanced age, and fracture. In the hospital, use of neuroleptics and narcotics and the presence of infection are less strongly associated with this syndrome.
authors.affiliation: Hebrew Rehabilitation Center for Aged, Boston, Mass.
authors.forename: J D
authors.initials: JD
authors.lastname: Schor
authors.forename: S E
authors.initials: SE
authors.lastname: Levkoff
authors.forename: L A
authors.initials: LA
authors.lastname: Lipsitz
authors.forename: C H
authors.initials: CH
authors.lastname: Reilly
authors.forename: P D
authors.initials: PD
authors.lastname: Cleary
authors.forename: J W
authors.initials: JW
authors.lastname: Rowe
authors.forename: D A
authors.initials: DA
authors.lastname: Evans
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001900:Boston; D003693:Delirium / Q000139:chemically induced / Q000209:etiology*; D005260:Female; D006760:Hospitalization; D006801:Humans; D015994:Incidence; D008297:Male; D015999:Multivariate Analysis; D016017:Odds Ratio; D011446:Prospective Studies; D012307:Risk Factors