a1 Faculty of Nursing Sciences, Laval University, Quebec, Quebec, Canada
a2 Centre for Excellence in Aging-Research Unit, Quebec, Quebec, Canada
a3 St. Mary's Research Centre, St Mary's Hospital, Montreal, Quebec, Canada
a4 Department of Psychiatry, St Mary's Hospital, Montreal, Quebec, Canada
a5 Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec, Canada
a6 Department of Psychiatry, McGill University, Montreal, Quebec, Canada
a7 Division of Geriatric Medicine, Jewish General Hospital, Montreal, Quebec, Canada
a8 Donald Berman Maimonides Geriatric Center, Montreal, Quebec, Canada
a9 Département de médecine familiale, Institut Universitaire de Gériatrie de Montréal, Université de Montréal, Montreal, Quebec, Canada
Background: Delirium among long-term care (LTC) residents is frequent and is associated with increased morbidity and mortality. Identification of clinical changes during the prodromal phase of delirium could lead to prevention of a full-blown episode and perhaps limit the deleterious consequences of this syndrome. The aim of the present study was to identify clinical changes observable in the 2-week period prior to the onset of full-blown delirium.
Methods: Long-term care (LTC) residents aged 65 years and over, with or without dementia were eligible for this nested case-control study. Delirium was assessed weekly over a 6-month period using the Confusion Assessment Method. Cases with incident delirium were matched by time since enrolment to one or more controls without delirium.
Results: When compared to the controls, LTC residents who developed delirium (cases = 85) were more likely to have new-onset perceptual disturbances (OR = 4.75; 95% CI 1.65–13.66) and disorganized thinking (OR = 3.09; 95% CI 1.33–7.19) and a worsening of the Mini-Mental State Examination (MMSE) item measuring registration (OR = 2.59; 95% CI 1.24–5.41) during the preceding 2 weeks. However, the frequency of these changes was low. Residents with at least 3 clinical changes were more likely to develop delirium than those without any clinical change (OR = 2.52; 95% CI 1.08–5.87).
Conclusions: This study provides evidence of clinical changes during the prodromal phase of delirium among LTC residents. More studies are needed to further explore the role and relevance of these clinical changes as warning signs of imminent delirium.
(Received January 30 2012)
(xxxMarch 03 2012)
(xxxApril 19 2012)
(Accepted April 25 2012)
(Online publication May 30 2012)
c1 Correspondence should be addressed to: Dr. Philippe Voyer, RN, PhD, Faculty of Nursing Sciences, Laval University, Pavillon Ferdinand-Vandry, Room 3445, 1050, rue de la Médecine, Quebec, QC, Canada, G1V 0A6. Phone: +1 418 656 2131; ext: 8799; Fax: +1 418 656 7747. Email: email@example.com.