title: Underdiagnosis of delirium on admission and prediction of patients who will develop delirium during their inpatient stay: a pilot study.
abstract: BACKGROUND
  The study aimed to determine the prevalence and documentation of delirium among the elderly and if the Clock Drawing Test (CDT) can be used to predict which patients had delirium on admission and those who may develop delirium during their stay in acute medical wards.
  
  
  METHODS
  A single researcher performed the Mini-Mental State Examination (MMSE) and CDT on admission and discharge of 57 elderly adults at the National University Hospital, Singapore. Delirium was defined as a ≥ 3-point improvement or ≥ 2-point decline in MMSE scores from admission to discharge, where a fall denotes development of delirium and a rise denotes resolution. The case notes of the same patients were reviewed for documentation of delirium. All inpatients from two acute medical wards were examined. One CDT score and a pair of MMSE scores were collected from each patient.
  
  
  RESULTS
  A total of 57 patients (28 male, 29 female) were involved in the study. Their mean age was 76.0 ± 8.7 years. The prevalence of delirium based on MMSE scores was 40.4%; 16 patients had delirium on admission while seven developed delirium during their inpatient stay. However, delirium was documented in the case notes of only 7 (30%) of the 23 patients. CDT score was better than baseline MMSE score at predicting a decline in MMSE score.
  
  
  CONCLUSIONS
  The prevalence of delirium in the acute medical setting is high but underdiagnosed. The CDT may be a good screening tool to identify patients at risk of delirium during their inpatient stay. Baseline cognition screening should be performed in every elderly patient admitted to hospital.
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, Singapore.
authors.forename: Yuin Cheng
authors.initials: YC
authors.lastname: Chin
authors.affiliation: Saw Swee Hock School of Public Health, National University of Singapore, Singapore.
authors.forename: Gerald Choon Huat
authors.initials: GC
authors.lastname: Koh
authors.affiliation: Department of Nursing, National University Hospital, Singapore.
authors.forename: Yee Kian
authors.initials: YK
authors.lastname: Tay
authors.affiliation: Department of Psychiatric Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors.forename: Chay Hoon
authors.initials: CH
authors.lastname: Tan
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, Singapore.
authors.forename: Reshma Aziz
authors.initials: RA
authors.lastname: Merchant
mesh_terms: D000368:Aged; D003071:Cognition / Q000502:physiology*; D003693:Delirium / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D003951:Diagnostic Errors; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007297:Inpatients; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010865:Pilot Projects; D015995:Prevalence; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D012846:Singapore / Q000453:epidemiology
keywords: clock drawing test; cognitive impairment in medical wards; delirium; elderly inpatients
references.citation: Chest. 2003 Dec;124(6):2267-74
references.pmid: 14665510
references.citation: Am J Med. 1994 Sep;97(3):278-88
references.pmid: 8092177
references.citation: J Am Geriatr Soc. 1986 Aug;34(8):579-85
references.pmid: 3088089
references.citation: J Am Geriatr Soc. 1992 Aug;40(8):829-38
references.pmid: 1634729
references.citation: CMAJ. 2002 Oct 1;167(7):753-9
references.pmid: 12389836
references.citation: J Am Geriatr Soc. 2002 Oct;50(10):1723-32
references.pmid: 12366629
references.citation: Arch Clin Neuropsychol. 1996;11(6):529-39
references.pmid: 14588458
references.citation: J Am Geriatr Soc. 1997 Feb;45(2):174-8
references.pmid: 9033515
references.citation: J Am Geriatr Soc. 2005 May;53(5):867-70
references.pmid: 15877566
references.citation: Dement Geriatr Cogn Disord. 1999 Sep-Oct;10(5):389-92
references.pmid: 10473945
references.citation: J Psychiatr Res. 1975 Nov;12(3):189-98
references.pmid: 1202204
references.citation: J Am Geriatr Soc. 1991 Sep;39(9):876-80
references.pmid: 1885862
references.citation: Int J Geriatr Psychiatry. 2000 Jun;15(6):548-61
references.pmid: 10861923
references.citation: Dement Geriatr Cogn Disord. 1999 Sep-Oct;10(5):393-400
references.pmid: 10473946
references.citation: J Am Geriatr Soc. 1988 Jun;36(6):525-30
references.pmid: 2897391
references.citation: Dement Geriatr Cogn Disord. 1999 Sep-Oct;10(5):319-24
references.pmid: 10473931
references.citation: Ann Intern Med. 1990 Dec 15;113(12):941-8
references.pmid: 2240918
references.citation: J Neuropsychiatry Clin Neurosci. 2003 Spring;15(2):200-7
references.pmid: 12724462
references.citation: Arch Intern Med. 2001 Nov 12;161(20):2467-73
references.pmid: 11700159
references.citation: Rev Med Chil. 2005 Dec;133(12):1449-54
references.pmid: 16446872
references.citation: J Am Geriatr Soc. 1992 Jun;40(6):579-84
references.pmid: 1587974
references.citation: Ann Intern Med. 1993 Sep 15;119(6):474-81
references.pmid: 8357112
references.citation: J Gen Intern Med. 1998 Apr;13(4):234-42
references.pmid: 9565386
references.citation: J Am Geriatr Soc. 1992 Jun;40(6):601-6
references.pmid: 1587979
references.citation: J Am Geriatr Soc. 1992 Sep;40(9):922-35
references.pmid: 1512391
references.citation: J Am Geriatr Soc. 1994 Aug;42(8):809-15
references.pmid: 8046190