title: Outcome of delirium in critically ill patients: systematic review and meta-analysis.
abstract: OBJECTIVE
  To determine the relation between delirium in critically ill patients and their outcomes in the short term (in the intensive care unit and in hospital) and after discharge from hospital.
  
  
  METHODS
  Systematic review and meta-analysis of published studies.
  
  
  METHODS
  PubMed, Embase, CINAHL, Cochrane Library, and PsychINFO, with no language restrictions, up to 1 January 2015.
  Reports were eligible for inclusion if they were prospective observational cohorts or clinical trials of adults in intensive care units who were assessed with a validated delirium screening or rating system, and if the association was measured between delirium and at least one of four clinical endpoints (death during admission, length of stay, duration of mechanical ventilation, and any outcome after hospital discharge). Studies were excluded if they primarily enrolled patients with a neurological disorder or patients admitted to intensive care after cardiac surgery or organ/tissue transplantation, or centered on sedation management or alcohol or substance withdrawal. Data were extracted on characteristics of studies, populations sampled, identification of delirium, and outcomes. Random effects models and meta-regression analyses were used to pool data from individual studies.
  
  
  RESULTS
  Delirium was identified in 5280 of 16,595 (31.8%) critically ill patients reported in 42 studies. When compared with control patients without delirium, patients with delirium had significantly higher mortality during admission (risk ratio 2.19, 94% confidence interval 1.78 to 2.70; P<0.001) as well as longer durations of mechanical ventilation and lengths of stay in the intensive care unit and in hospital (standard mean differences 1.79 (95% confidence interval 0.31 to 3.27; P<0.001), 1.38 (0.99 to 1.77; P<0.001), and 0.97 (0.61 to 1.33; P<0.001), respectively). Available studies indicated an association between delirium and cognitive impairment after discharge.
  
  
  CONCLUSIONS
  Nearly a third of patients admitted to an intensive care unit develop delirium, and these patients are at increased risk of dying during admission, longer stays in hospital, and cognitive impairment after discharge.
authors.affiliation: D'OR Institute for Research and Education, Rio de Janeiro, Brazil.
authors.forename: Jorge I F
authors.initials: JI
authors.lastname: Salluh
authors.affiliation: Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Han
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Eric B
authors.initials: EB
authors.lastname: Schneider
authors.affiliation: Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Neeraja
authors.initials: N
authors.lastname: Nagaraja
authors.affiliation: Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
authors.forename: Gayane
authors.initials: G
authors.lastname: Yenokyan
authors.affiliation: Elaine and Sydney Sussman Cardiac Catheterization Laboratories, Cardiovascular Division, University of Miami Miller School of Medicine, Miami, FL, USA.
authors.forename: Abdulla
authors.initials: A
authors.lastname: Damluji
authors.affiliation: D'OR Institute for Research and Education, Rio de Janeiro, Brazil Department of Internal Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Rodrigo B
authors.initials: RB
authors.lastname: Serafim
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, Neurology, Neurosurgery, and Radiology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors.forename: Robert D
authors.initials: RD
authors.lastname: Stevens
mesh_terms: D000328:Adult; D003072:Cognition Disorders / Q000401:mortality / Q000523:psychology; D003422:Critical Care / Q000706:statistics & numerical data; D016638:Critical Illness / Q000401:mortality / Q000523:psychology*; D003693:Delirium / Q000401:mortality / Q000628:therapy*; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D010351:Patient Discharge / Q000706:statistics & numerical data; D012121:Respiration, Artificial / Q000401:mortality; D016896:Treatment Outcome