Delirium etiology subtypes and their effect on six-month function and cognition in older emergency department patients.

ABSTRACTBackground:Delirium is heterogeneous and can vary by etiology. OBJECTIVES: We sought to determine how delirium subtyped by etiology affected six-month function and cognition. DESIGN: Prospective cohort study. SETTING: Tertiary care, academic medical center. PARTICIPANTS: A total of 228 hospitalized patients > 65 years old were admitted from the emergency department (ED). MEASUREMENTS: The modified Brief Confusion Assessment Method was used to determine delirium in the ED. Delirium etiology was determined by three trained physician reviewers using a Delirium Etiology checklist. Pre-illness and six-month function and cognition were determined using the Older American Resources and Services Activities of Daily Living (OARS ADL) questionnaire and the short-form Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). Multiple linear regression was performed to determine if delirium etiology subtypes were associated with six-month function and cognition adjusted for baseline OARS ADL and IQCODE. Two-factor interactions were incorporated to determine pre-illness function or cognition-modified relationships between delirium subtypes and six-month function and cognition. RESULTS: In patients with poorer pre-illness function only, delirium secondary to metabolic disturbance (ß coefficient = -2.9 points, 95%CI: -0.3 to -5.6) and organ dysfunction (ß coefficient = -4.3 points, 95%CI: -7.2 to -1.4) was significantly associated with poorer six-month function. In patients with intact cognition only, delirium secondary to central nervous system insults was significantly associated with poorer cognition (ß coefficient = 0.69, 95%CI: 0.19 to 1.20). CONCLUSIONS: Delirium is heterogeneous and different etiologies may have different prognostic implications. Furthermore, the effect of these delirium etiologies on outcome may be dependent on the patient's pre-illness functional status and cognition.

Emergency Department Interventions and Their Effect on Delirium's Natural Course: The Folly May be in the Foley.

BACKGROUND: Delirium frequently affects older emergency department (ED) patients and has been associated with accelerated cognitive and functional decline, increased length of stay (LOS), and higher in- and out-of-hospital mortality. OBJECTIVES: Care provided in the ED may have downstream effects on delirium duration during hospitalization. This study aimed to identify the modifiable factors of ED care associated with delirium duration in patients admitted to the hospital through the ED. MATERIALS AND METHODS: This prospective cohort study enrolled ED patients who were 65 years and older and admitted to the hospital. Delirium was determined in the ED and during the first 7 days of hospitalization using the modified Brief Confusion Assessment Method. All delirious patients and a random selection (17%) of nondelirious patients were also enrolled. ED LOS, opioid administration, benzodiazepine administration, anticholinergic medication administration, and bladder catheter placement were obtained by medical record review. Multivariable proportional odds logistic regression was performed to determine if each of the factors was associated with delirium duration after adjusting for age, dementia, baseline function, comorbidity burden, severity of illness, nursing home residence, and central nervous system insult. RESULTS: A total of 228 patients were enrolled. ED bladder catheter placement was significantly associated (adjusted proportional odds ratio = 3.1, 95% confidence interval: 1.3 to 7.4) with increased delirium duration after adjusting for confounders. ED LOS, opioid administration, benzodiazepine administration, and anticholinergic burden, however, were not. CONCLUSIONS: ED bladder catheter placement was significantly associated with delirium duration and may present an opportunity for intervention.