title: Prevalence and detection of delirium in elderly emergency department patients.
abstract: BACKGROUND
  Delirium is a complex medical disorder associated with high morbidity and mortality among elderly patients. The goals of our study were to determine the prevalence of delirium in emergency department (ED) patients aged 65 years and over and to determine the sensitivity and specificity of a conventional clinical assessment by an ED physician for the detection of delirium in the same population.
  
  
  METHODS
  All elderly patients presenting to the ED in a primary acute care, university-affiliated hospital who were triaged to the observation room on a stretcher because of the severity of their illness were screened for delirium by a research psychiatrist using the Mini-Mental State Examination and the Confusion Assessment Method. The diagnosis of "delirium" or an equivalent term by the ED physician was determined by 2 methods: completion of a mental status checklist by the ED physician and chart review. The prevalence of delirium and the sensitivity and specificity of the ED physician's clinical assessment were calculated with their 95% confidence intervals. The demographic and clinical characteristics of patients with detected delirium and those with undetected delirium were compared.
  
  
  RESULTS
  A sample of 447 patients was screened. The prevalence of delirium was 9.6% (95% confidence interval 6.9%-12.4%). The sensitivity of the detection of delirium by the ED physician was 35.3% and the specificity, 98.5%. Most patients with delirium had neurologic or pulmonary diseases, and most patients with detected delirium had neurologic diseases.
  
  
  CONCLUSIONS
  Despite the relatively high prevalence of delirium in elderly ED patients, the sensitivity of a conventional clinical assessment for this condition is low. There is a need to improve the detection of delirium by ED physicians.
authors.affiliation: Department of Psychiatry, McGill University, Montreal, Que. geriatricpsych@hotmail.com
authors.forename: M
authors.initials: M
authors.lastname: Elie
authors.forename: F
authors.initials: F
authors.lastname: Rousseau
authors.forename: M
authors.initials: M
authors.lastname: Cole
authors.forename: F
authors.initials: F
authors.lastname: Primeau
authors.forename: J
authors.initials: J
authors.lastname: McCusker
authors.forename: F
authors.initials: F
authors.lastname: Bellavance
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D016001:Confidence Intervals; D003221:Confusion / Q000175:diagnosis / Q000453:epidemiology; D003693:Delirium / Q000175:diagnosis / Q000453:epidemiology*; D003710:Demography; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data; D005260:Female; D006784:Hospitals, Teaching; D006801:Humans; D008171:Lung Diseases / Q000175:diagnosis / Q000453:epidemiology; D008297:Male; D008499:Medical Records; D008609:Mental Status Schedule; D009422:Nervous System Diseases / Q000175:diagnosis / Q000453:epidemiology; D015995:Prevalence; D011792:Quebec / Q000453:epidemiology; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D016037:Single-Blind Method