Impact of delirium on clinical outcome in critically ill patients: a meta-analysis

Department of Critical Care Medicine, Jinhua Municipal Central Hospital, 351#, Mingyue Road, Jinhua, Zhejiang Province, 321000, P.R. China. Electronic address: .
General hospital psychiatry (Impact Factor: 2.9). 12/2012; 35(2). DOI: 10.1016/j.genhosppsych.2012.11.003
Source: PubMed

ABSTRACT CONTEXT: Delirium is prevalent in the intensive care unit (ICU) and has been associated with negative clinical outcomes. However, a quantitative and systematic assessment of published studies has not been conducted. OBJECTIVE: Meta-analysis of clinical observational studies was performed to investigate the association between delirium and clinical outcomes. DATA SOURCES AND STUDY SELECTION: Relevant studies were identified by investigators from databases including Medline, Embase, OVID and EBSCO from inception to May 2012. Studies that reported the association of delirium with clinical outcomes in critical care setting were included. DATA EXTRACTION: Data were extracted independently by reviewers and summary effects were obtained using random effects model. DATA SYNTHESIS: Of the 16 studies included, 14 studies involving 5891 patients reported data on mortality, and delirious patients had higher mortality rate than non-delirious patients (odds ratio [OR]: 3.22; 95% confidence interval [CI]: 2.30-4.52). Delirious patients had higher rate of complications (OR: 6.5; 95% CI: 2.7-15.6), and were more likely to be discharged to skilled placement (OR: 2.59; 95% CI: 1.59-4.21). Furthermore, patients with delirium had longer length of stay in both ICU (weighted mean difference [WMD]: 7.32 days; 95% CI: 4.63-10.01) and hospital (WMD: 6.53 days; 95% CI: 3.03-10.03), and they spent more time on mechanical ventilation (WMD: 7.22 days; 95% CI: 5.15-9.29). CONCLUSION: Delirium in critically ill patients is associated with higher mortality rate, more complications, longer duration of mechanical ventilation, and longer length of stay in ICU and hospital.

  • BMJ Clinical Research 11/2014; 349:g7265. DOI:10.1136/bmj.g7265 · 14.09 Impact Factor
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    ABSTRACT: To determine the attributable mortality caused by delirium in critically ill patients. Prospective cohort study. 32 mixed bed intensive care unit in the Netherlands, January 2011 to July 2013. 1112 consecutive adults admitted to an intensive care unit for a minimum of 24 hours. Trained observers evaluated delirium daily using a validated protocol. Logistic regression and competing risks survival analyses were used to adjust for baseline variables and a marginal structural model analysis to adjust for confounding by evolution of disease severity before the onset of delirium. Mortality during admission to an intensive care unit. Among 1112 evaluated patients, 558 (50.2%) developed at least one episode of delirium, with a median duration of 3 days (interquartile range 2-7 days). Crude mortality was 94/558 (17%) in patients with delirium compared with 40/554 (7%) in patients without delirium (P<0.001). Delirium was significantly associated with mortality in the multivariable logistic regression analysis (odds ratio 1.77, 95% confidence interval 1.15 to 2.72) and survival analysis (subdistribution hazard ratio 2.08, 95% confidence interval 1.40 to 3.09). However, the association disappeared after adjustment for time varying confounders in the marginal structural model (subdistribution hazard ratio 1.19, 95% confidence interval 0.75 to 1.89). Using this approach, only 7.2% (95% confidence interval -7.5% to 19.5%) of deaths in the intensive care unit were attributable to delirium, with an absolute mortality excess in patients with delirium of 0.9% (95% confidence interval -0.9% to 2.3%) by day 30. In post hoc analyses, however, delirium that persisted for two days or more remained associated with a 2.0% (95% confidence interval 1.2% to 2.8%) absolute mortality increase. Furthermore, competing risk analysis showed that delirium of any duration was associated with a significantly reduced rate of discharge from the intensive care unit (cause specific hazard ratio 0.65, 95% confidence interval 0.55 to 0.76). Overall, delirium prolongs admission in the intensive care unit but does not cause death in critically ill patients. Future studies should focus on episodes of persistent delirium and its long term sequelae rather than on acute mortality.Trial registration NCT01905033. © Klein Klouwenberg et al 2014.
    BMJ Clinical Research 11/2014; 349(nov24 16):g6652. DOI:10.1136/bmj.g6652 · 14.09 Impact Factor
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    ABSTRACT: Introduction Delirium is common in critically ill patients and impact in-hospital mortality in patients with pneumonia. The aim of the study was to evaluate the prevalence of delirium symptoms during hospitalization in patients with severe pneumonia and their impact on one-year mortality. Methods This was an observational, retrospective, cohort study of consecutive patients admitted to the respiratory high dependency unit of the San Gerardo University Hospital, Monza, Italy, between January 2009 and December 2012 with a diagnosis of severe pneumonia. A search through the charts looking for ten key words associated with delirium (confusion, disorientation, altered mental status, delirium, agitation, inappropriate behavior, mental status change, inattention, hallucination, lethargy) was performed by a multidisciplinary team. The primary endpoint was mortality at one-year follow-up. Secondary endpoint was in-hospital mortality. Results A total of 172 patients were enrolled (78 % males; median age 75 years). At least one delirium symptom was detected in 53 patients (31 %) during hospitalization. The prevalence of delirium symptoms was higher among those who died during hospitalization vs. those who survived (44 vs. 27 %, p = 0.049, respectively). Seventy-one patients (46 %) died during the one-year follow-up. The prevalence of at least one delirium symptom was higher among those who died than those who survived during the one-year follow-up (39 vs. 21 %, p = 0.014, respectively). At the multivariable logistic regression analysis, after adjustment for age, comorbidities and severe sepsis, the presence of at least one delirium symptom during hospitalization was an independent predictor of one-year mortality (OR 2.35; 95 % CI 1.13–4.90; p = 0.023). Conclusions Delirium symptoms are independent predictors of one-year mortality in hospitalized patients with severe pneumonia. Further studies should confirm our results using prospective methods of collecting data.
    Aging - Clinical and Experimental Research 01/2015; DOI:10.1007/s40520-014-0297-9 · 1.01 Impact Factor


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May 22, 2014