488: DELIRIUM PREDICTS MORTALITY AND LENGTH OF STAY BUT NOT FUNCTIONAL INDEPENDENCE POST-ICU DISCHARGE

Abstract

Introduction: Delirium is common in the intensive care unit (ICU) and can complicate the existing critical illness. Yet, there is a paucity of information about delirium incidence and its effect on patient’s outcomes in the developing countries where it can be misdiagnosed or undetected. The aim of this study was to determine the incidence, predictors, and the association of delirium with short-term (ICU length of stay, hospital length of stay, and in-hospital mortality) and long-term (activities of daily living and mortality at 4 months after discharge) outcomes among ICU patients. Methods: This was a prospective cohort study of 111 patients who were conscious, > 18 years old, and admitted to the ICU for ≥ 8 hours. Untestable patients (Richmond agitation score of -4 or -5, mental disability, receptive aphasia, and/or visual or auditory impairment) were excluded. The Confusion Assessment Method for the ICU (CAM-ICU) was utilized to assess delirium while Katz Activities of Daily Living index was used to assess functional independence at 4 months after discharge. Delirium was assessed daily during ICU stay and continued until death or ICU discharge. Multivariable logistic regression and student’s t-test were used in the analyses. Results: Delirium was found in 32% of patients. The severity of illness measured by APACHE II (OR 1.28, p<.001) score was an independent predictor of delirium in multivariable analysis controlling age, sex, and sedation. Patients with delirium had significantly longer ICU and hospital stay (12.4±11.9 and 22.2±19.4 respectively) compared to those without delirium (6.4±5.8 and 14.7±17.4, respectively), p<.05. Delirium was associated with increased in-hospital and 4-month mortality (OR 12.1 and 7.1, p<.05) but not with activities of daily living (OR=1.4, p=.69). Conclusions: Delirium has a substantial effect on ICU and hospital length of stay and both in-hospital and post discharge mortality. The mechanistic link between delirium and mortality remains unclear. This warrants further investigation to better understand how delirium contributes to mortality, and to determine whether the current interventions to manage delirium affect mortality among ICU patients.