title: Risk factors for incident delirium in an acute general medical setting: a retrospective case-control study.
abstract: OBJECTIVE
  To determine predisposing and precipitating risk factors for incident delirium in medical patients during an acute hospital admission.
  
  
  BACKGROUND
  Incident delirium is the most common complication of hospital admission for older patients. Up to 30% of hospitalised medical patients experience incident delirium. Determining risk factors for delirium is important for identifying patients who are most susceptible to incident delirium.
  
  
  METHODS
  Retrospective case-control study with two controls per case.
  
  
  METHODS
  An audit tool was used to review medical records of patients admitted to acute medical units for data regarding potential risk factors for delirium. Data were collected between August 2013 and March 2014 at three hospital sites of a healthcare organisation in Melbourne, Australia. Cases were 161 patients admitted to an acute medical ward and diagnosed with incident delirium between 1 January 2012 and 31 December 2013. Controls were 321 patients sampled from the acute medical population admitted within the same time range, stratified for admission location and who did not develop incident delirium during hospitalisation.
  
  
  RESULTS
  Identified using logistic regression modelling, predisposing risk factors for incident delirium were dementia, cognitive impairment, functional impairment, previous delirium and fracture on admission. Precipitating risk factors for incident delirium were use of an indwelling catheter, adding more than three medications during admission and having an abnormal sodium level during admission.
  
  
  CONCLUSIONS
  Multiple risk factors for incident delirium exist; patients with a history of delirium, dementia and cognitive impairment are at greatest risk of developing delirium during hospitalisation.
  
  
  CONCLUSIONS
  Nurses and other healthcare professionals should be aware of patients who have one or more risk factors for incident delirium. Knowledge of risk factors for delirium has the potential to increase the recognition and understanding of patients who are vulnerable to delirium. Early recognition and prevention of delirium can contribute to improved patients safety and reduction in harm.
authors.affiliation: School of Nursing and Midwifery, Deakin University, Geelong, Vic., Australia.|Centre for Quality and Patient Safety Research, Faculty of Health, Deakin University, Burwood, Vic., Australia.
authors.forename: Emily Jane
authors.initials: EJ
authors.lastname: Tomlinson
authors.affiliation: School of Nursing and Midwifery, Deakin University, Geelong, Vic., Australia.|Centre for Quality and Patient Safety Research, Faculty of Health, Deakin University, Burwood, Vic., Australia.
authors.forename: Nicole M
authors.initials: NM
authors.lastname: Phillips
authors.affiliation: Biostatistics Unit, Faculty of Health, Deakin University, Geelong, Vic., Australia.
authors.forename: Mohammadreza
authors.initials: M
authors.lastname: Mohebbi
authors.affiliation: School of Nursing and Midwifery, Deakin University, Geelong, Vic., Australia.|Centre for Quality and Patient Safety Research, Faculty of Health, Deakin University, Burwood, Vic., Australia.|Centre for Nursing Research, Deakin University and Monash Health Partnership, Monash Health, Clayton, Vic., Australia.
authors.forename: Alison M
authors.initials: AM
authors.lastname: Hutchinson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001315:Australia; D016022:Case-Control Studies; D003422:Critical Care / Q000706:statistics & numerical data*; D003693:Delirium / Q000175:diagnosis* / Q000209:etiology*; D003704:Dementia / Q000150:complications* / Q000175:diagnosis*; D005260:Female; D015577:Geriatric Assessment; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D016015:Logistic Models; D008297:Male; D010361:Patients / Q000523:psychology*; D012189:Retrospective Studies; D012307:Risk Factors
keywords: acute care; case-control; delirium; medical patients; risk factor