Eric Belzile

Bio: Eric Belzile is an academic researcher from McGill University. The author has contributed to research in topics: Delirium & Depression (differential diagnoses). The author has an hindex of 22, co-authored 55 publications receiving 2480 citations. Previous affiliations of Eric Belzile include Jewish General Hospital.

Delirium predicts 12-month mortality.

Abstract: Background Delirium has not been found to be a significant predictor of postdischarge mortality, but previous research has methodologic limitations including small sample sizes and inadequate control of confounding. This study aimed to determine the independent effects of presence of delirium, type of delirium (incident vs prevalent), and severity of delirium symptoms on 12-month mortality among older medical inpatients. Methods A prospective, observational study of 2 cohorts of medical inpatients was conducted with patients 65 years or older: 243 patients had prevalent or incident delirium, and 118 controls had no delirium. Baseline measures included presence of delirium and/or dementia, severity of delirium symptoms, physical function, comorbidity, and physiological and clinical severity of illness. Mortality during the 12 months after enrollment was analyzed with the Cox proportional hazards model with adjustment for covariates. Results The unadjusted hazard ratio of delirium with mortality was 3.44 (95% confidence interval, 2.05-5.75); the adjusted hazard ratio was 2.11 (95% confidence interval, 1.18-3.77). The effect of delirium was sustained over the entire 12-month period after adjustment for covariates and was stronger among patients without dementia. Among patients with dementia, there was a weak, nonsignificant effect of delirium on survival. After adjustment for covariates, mortality did not differ between patients with incident and prevalent delirium, but among patients with delirium without dementia, greater severity of delirium symptoms was associated with higher mortality. Conclusions Delirium is an independent marker for increased mortality among older medical inpatients during the 12 months after hospital admission. It is a particularly important prognostic marker among patients without dementia.

Delirium in older medical inpatients and subsequent cognitive and functional status: a prospective study

Abstract: Background: Delirium in older hospital inpatients appears to be associated with various adverse outcomes. The limitations of previous research on this association have included small sample sizes, short follow-up periods and lack of consideration of important confounders or modifiers, such as severity of illness, comorbidity and dementia. The objective of this study was to determine the prognostic significance of delirium, with or without dementia, for cognitive and functional status during the 12 months after hospital admission, independent of premorbid function, comorbidity, severity of illness and other potentially confounding variables. Methods: Patients 65 years of age and older who were admitted from the emergency department to the medical services were screened for delirium during their first week in hospital. Two cohorts were enrolled: patients with prevalent or incident delirium and patients without delirium, but similar in age and cognitive impairment. The patients were followed up at 2, 6 and 12 months after hospital admission. Analyses were conducted for 4 patient groups: 56 with delirium, 53 with dementia, 164 with both conditions and 42 with neither. Baseline measures included delirium (Confusion Assessment Method), dementia (Informant Questionnaire on Cognitive Decline in the Elderly), physical function (Barthel Index [BI] and premorbid instrumental activities of daily living, IADL), the Mini-Mental State Examination (MMSE), comorbidity, and physiologic and clinical severity of illness. Outcome variables measured at follow-up were the MMSE, Barthel Index, IADL and admission to a long-term care facility. Results: After adjustment for covariates, the mean differences in MMSE scores at follow-up between patients with and without delirium were –4.99 (95% confidence interval [CI] –7.17 to –2.81) for patients with dementia and –3.36 (95% CI –6.15 to –0.58) for those without dementia. At 12 months, the adjusted mean differences in the BI were –16.45 (95% CI –27.42 to –5.50) and –13.89 (95% CI –28.39 to 0.61) for patients with and without dementia respectively. Patients with both delirium and dementia were more likely to be admitted to long-term care than those with neither condition (adjusted odds ratio 3.18, 95% CI 1.19 to 8.49). Dementia but not delirium predicted worse IADL scores at follow-up. Unadjusted analyses yielded similar results. Interpretation: For older patients with and without dementia, delirium is an independent predictor of sustained poor cognitive and functional status during the year after a medical admission to hospital.

Does delirium increase hospital stay

Abstract: Objectives: To determine the effects of prevalent and incident delirium on length of hospital stay. Design: Prospective cohort study, comparing (1) length of stay after admission in cases of prevalent delirium versus controls without prevalent delirium with (2) length of stay after diagnosis in cases of incident delirium versus controls matched by day of diagnosis. Setting: The medical services of a primary, acute care hospital. Participants: Medical admissions of patients aged 65 and older from the emergency department with delirium diagnosed during the first week in hospital. Patients admitted to intensive care or oncology and those with a primary diagnosis of stroke were excluded. A sample of those without delirium was also enrolled. Measurements: Delirium was diagnosed using the Confusion Assessment Method. Data on length of stay and diagnosis-related groups (DRGs) were abstracted from administrative data. Measures of covariates included the Informant Questionnaire on Cognitive Decline in the Elderly, the Delirium Index, the instrumental activities of daily living questionnaire from the Older American Resources and Services project, the Charlson Comorbidity Index, the Clinical Severity Scale, and the Acute Physiology Score. Results: The study sample comprised 359 patients: 204 with prevalent delirium, 37 with incident delirium, and 118 without delirium. After controlling for covariates, prevalent delirium was not associated with a significantly longer hospital stay, but incident delirium was associated with an excess stay after diagnosis of 7.78 days (95% confidence interval=3.07, 12.48). Similar results were obtained using log-transformed or DRG-adjusted estimates of length of stay. Conclusion: In older medical inpatients, incident but not prevalent delirium is an important predictor of longer hospital stay. Interventions to prevent incident delirium may reduce length of stay.

The Course of Delirium in Older Medical Inpatients: A Prospective Study

Abstract: Objectives To describe the clinical course and outcomes of delirium up to 12 months after diagnosis, the relationship between the in-hospital clinical course and post-discharge outcomes, and the role of dementia in both the clinical course and outcomes of delirium. Design Prospective cohort study. Setting Medical wards of a 400-bed, university-affiliated, primary acute care hospital in Montreal. Patients Cohort of 193 medical inpatients aged 65 and over with delirium diagnosed at admission or during the first week in hospital, who were discharged alive from hospital. Measurements and main results Study outcomes included cognitive impairment and activities of daily living (standardized, face-to-face clinical instruments at 1-, 2-, 6-, and 12-month follow-up), and mortality. Dementia, severity of illness, comorbidity, and sociodemographic variables were measured at time of diagnosis. Several measures of the in-hospital course of delirium were constructed. The mean numbers of symptoms of delirium at diagnosis and 12-month follow-up, respectively, were 4.5 and 3.5 in the subgroup of patients with dementia and 3.4 and 2.2 among those without dementia. Inattention, disorientation, and impaired memory were the most persistent symptoms in both subgroups. In multivariate analyses, pre-morbid and admission level of function, nursing home residence, and slower recovery during the initial hospitalization were associated with worse cognitive and functional outcomes but not mortality. Conclusions Among patients with and without dementia, symptoms of delirium persist up to 12 months after diagnosis. Quicker in-hospital recovery is associated with better outcomes.

The Identification of Seniors At Risk Screening Tool: Further Evidence of Concurrent and Predictive Validity

Abstract: Objectives: To evaluate the validity of the Identification of Seniors at Risk (ISAR) screening tool for detecting severe functional impairment and depression and predicting increased depressive symptoms and increased utilization of health services. Setting: Four university-affiliated hospitals in Montreal. Design: Data from two previous studies were available: Study 1, in which the ISAR scale was developed (n=1,122), and Study 2, in which it was used to identify patients for a randomized trial of a nursing intervention (n=1,889 with administrative data, of which 520 also had clinical data). Participants: Patients aged 65 and older who were to be released from an emergency department (ED). Measurements: Baseline validation criteria included premorbid functional status in both studies and depression in Study 2 only. Increase in depressive symptoms at 4-month follow-up was assessed in Study 2. Information on health services utilization during the 5 months after the ED visit (repeat ED visits and hospitalization in both studies, visits to community health centers in Study 2) was available by linkage with administrative databases. Results: Estimates of the area under the receiver operating characteristic curve (AUC) for concurrent validity of the ISAR scale for severe functional impairment and depression ranged from 0.65 to 0.86. Estimates of the AUC for predictive validity for increased depressive symptoms and high utilization of health services ranged from 0.61 to 0.71. Conclusion: The ISAR scale has acceptable to excellent concurrent and predictive validity for a variety of outcomes, including clinical measures and utilization of health services.

Multiple Imputation for Nonresponse in Surveys

Abstract: 25. Multiple Imputation for Nonresponse in Surveys. By D. B. Rubin. ISBN 0 471 08705 X. Wiley, Chichester, 1987. 258 pp. £30.25.

Delirium as a predictor of mortality in mechanically ventilated patients in the intensive care unit

Abstract: ContextIn the intensive care unit (ICU), delirium is a common yet underdiagnosed form of organ dysfunction, and its contribution to patient outcomes is unclear.ObjectiveTo determine if delirium is an independent predictor of clinical outcomes, including 6-month mortality and length of stay among ICU patients receiving mechanical ventilation.Design, Setting, and ParticipantsProspective cohort study enrolling 275 consecutive mechanically ventilated patients admitted to adult medical and coronary ICUs of a US university-based medical center between February 2000 and May 2001. Patients were followed up for development of delirium over 2158 ICU days using the Confusion Assessment Method for the ICU and the Richmond Agitation-Sedation Scale.Main Outcome MeasuresPrimary outcomes included 6-month mortality, overall hospital length of stay, and length of stay in the post-ICU period. Secondary outcomes were ventilator-free days and cognitive impairment at hospital discharge.ResultsOf 275 patients, 51 (18.5%) had persistent coma and died in the hospital. Among the remaining 224 patients, 183 (81.7%) developed delirium at some point during the ICU stay. Baseline demographics including age, comorbidity scores, dementia scores, activities of daily living, severity of illness, and admission diagnoses were similar between those with and without delirium (P>.05 for all). Patients who developed delirium had higher 6-month mortality rates (34% vs 15%, P = .03) and spent 10 days longer in the hospital than those who never developed delirium (P<.001). After adjusting for covariates (including age, severity of illness, comorbid conditions, coma, and use of sedatives or analgesic medications), delirium was independently associated with higher 6-month mortality (adjusted hazard ratio [HR], 3.2; 95% confidence interval [CI], 1.4-7.7; P = .008), and longer hospital stay (adjusted HR, 2.0; 95% CI, 1.4-3.0; P<.001). Delirium in the ICU was also independently associated with a longer post-ICU stay (adjusted HR, 1.6; 95% CI, 1.2-2.3; P = .009), fewer median days alive and without mechanical ventilation (19 [interquartile range, 4-23] vs 24 [19-26]; adjusted P = .03), and a higher incidence of cognitive impairment at hospital discharge (adjusted HR, 9.1; 95% CI, 2.3-35.3; P = .002).ConclusionDelirium was an independent predictor of higher 6-month mortality and longer hospital stay even after adjusting for relevant covariates including coma, sedatives, and analgesics in patients receiving mechanical ventilation.

Delirium in older persons.

Abstract: The prevalence of delirium increases sharply with age, and about 20 percent of older patients have delirium at the time of hospital admission for any reason. This review summarizes the clinical manifestations of and risk factors for delirium and the evaluation of patients with this condition. It includes an update on the current understanding of the pathogenesis of delirium and provides guidance regarding practical measures to prevent this common complication.

Applied Linear Regression Models

Abstract: (1991). Applied Linear Regression Models. Journal of Quality Technology: Vol. 23, No. 1, pp. 76-77.