[Delirium Update: Risk Factors, Management, and Biomarkers].

INTRODUCTION: A delirium can be encountered in almost all hospital sectors. The prevalence varies between 20 and 40 % in internal medicine and surgical wards and between 50 and 60 % in palliative care and intensive care units. A delirium is characterized by impaired attention, consciousness, and cognitive impairment with acute onset and fluctuating course. People with delirium have inferior clinical outcomes, including higher mortality and more need for long-term care after discharge. This article first reviews the clinical and pathophysiologic basis of delirium, followed by a detailed description of individual risk profiles based on a prospective, hospital-wide cohort study (Delir-Path) conducted at the University Hospital Zurich. We will then give a brief update on diagnosis and management of delirium and an outlook on how neurophysiology and blood biomarkers can complement delirium care in the future.

Dose-dependent QTc interval prolongation under haloperidol and pipamperone in the management of delirium in a naturalistic setting.

Objective: Delirium is an acute, life-threatening neuropsychiatric disorder frequently occurring among hospitalized patients. Antipsychotic medications are often recommended for delirium management but are associated with cardiovascular risks. This study aimed to investigate the frequency and magnitude of QTc interval prolongation and clinically relevant side effects occurring in delirium patients managed with haloperidol and/or pipamperone. Methods: This descriptive retrospective cohort study evaluated 102 elderly (mean age: 73.2 years) inpatients with delirium treated with either haloperidol, pipamperone, a combination of both, or neither in a naturalistic setting over the course of up to 20 days or until the end of delirium. Results: A total of 86.3% of patients were treated with haloperidol and/or pipamperone at a mean daily haloperidol-equipotent dose of 1.2 ± 1 mg. Non-cardiovascular side effects were registered in 2.9% of all patients and correlated with higher scores on the Delirium Observation Screening Scale. They did not occur more frequently under antipsychotic treatment. The frequency of QTc interval prolongation was comparably common among all groups, but prolongation magnitude was higher under antipsychotic treatment. It was positively correlated with antipsychotic dosage and the total number of QTc interval-prolonging substances administered. Critical QTc interval prolongation was registered in 21.6% (n = 19) of patients in the group treated with antipsychotics compared to 14.3% (n = 2) of patients in the unmedicated group; however, the difference was not statistically significant. Polypharmacy was associated with a higher risk of critical QTc interval prolongation and increased mortality during delirium. Conclusion: Delirium treatment with haloperidol and/or pipamperone was not associated with a higher risk of QTc-interval prolongation in this naturalistic patient sample but was greater in magnitude and correlated with equipotent dosage and the number of QT interval-prolonging substances used. Polypharmacy was associated with higher mortality and increased risk of critical QTc prolongation.

Sex-specific clinical characteristics and treatment responses in delirium management: findings from a prospective cohort study in elderly patients.

Delirium incidence and phenotype differ between sexes. Sex differences in the selection of treatment strategies remain elusive. We evaluated sex-specific responses to non- and pharmacological management. In this observational prospective cohort study conducted at the University Hospital Zurich, Switzerland, 602 patients managed for delirium were analyzed. Remission and benefit ratios of treatments were calculated using Cox regression models. Baseline characteristics were similar in both sexes. Overall, 89% of all patients (540/602) received pharmacological management for delirium, most (77%) with one or two different medications. An equal number of male and female patients had either no medication ( P  = 0.321) or three and more medications ( P  = 0.797). Men had two different medications more often ( P  = 0.009), while women more frequently received one medication ( P  = 0.037). Remission rates within 20 days were higher in non-pharmacological treatment and similar between sexes, with odds of 1.36 in females, and 2.3 in males. Non-pharmacological treatment was equally efficacious in both sexes. Women who received supportive treatment and monotherapy had equal odds of remission. Men fared better with supportive care compared to pharmacologic therapies. Remission rates with different management strategies were similar between sexes. No sex differences were found regarding phenotypes, clinical course, and response to therapy.

Predisposing and precipitating risk factors for delirium in gastroenterology and hepatology: Subgroup analysis of 718 patients from a hospital-wide prospective cohort study.

Background and Aims: Delirium is the most common acute neuropsychiatric syndrome in hospitalized patients. Higher age and cognitive impairment are known predisposing risk factors in general hospital populations. However, the interrelation with precipitating gastrointestinal (GI) and hepato-pancreato-biliary (HPB) diseases remains to be determined. Patients and methods: Prospective 1-year hospital-wide cohort study in 29'278 adults, subgroup analysis in 718 patients hospitalized with GI/HPB disease. Delirium based on routine admission screening and a DSM-5 based construct. Regression analyses used to evaluate clinical characteristics of delirious patients. Results: Delirium was detected in 24.8% (178/718). Age in delirious patients (median 62 years [IQR 21]) was not different to non-delirious (median 60 years [IQR 22]), p = 0.45). Dementia was the strongest predisposing factor for delirium (OR 66.16 [6.31-693.83], p < 0.001). Functional impairment, and at most, immobility increased odds for delirium (OR 7.78 [3.84-15.77], p < 0.001). Patients with delirium had higher in-hospital mortality rates (18%; OR 39.23 [11.85-129.93], p < 0.001). From GI and HPB conditions, cirrhosis predisposed to delirium (OR 2.11 [1.11-4.03], p = 0.023), while acute renal failure (OR 4.45 [1.61-12.26], p = 0.004) and liver disease (OR 2.22 [1.12-4.42], p = 0.023) were precipitators. Total costs were higher in patients with delirium (USD 30003 vs. 10977; p < 0.001). Conclusion: Delirium in GI- and HPB-disease was not associated with higher age per se, but with cognitive and functional impairment. Delirium needs to be considered in younger adults with acute renal failure and/or liver disease. Clinicians should be aware about individual risk profiles, apply preventive and supportive strategies early, which may improve outcomes and lower costs.

Corrigendum: Risk Factors for Delirium Are Different in the Very Old: A Comparative One-Year Prospective Cohort Study of 5,831 Patients.

[This corrects the article DOI: 10.3389/fpsyt.2021.655087.].

Discharge Destinations of Delirious Patients: Findings From a Prospective Cohort Study of 27,026 Patients From a Large Health Care System.

OBJECTIVES: Delirium is known to contribute to increased rates of institutionalization and mortality. The full extent of adverse outcomes, however, remains understudied. We aimed to systematically assess the discharge destinations and mortality risk in delirious patients in a large sample across all hospital services. DESIGN: Pragmatic prospective cohort study of consecutive admissions to a large health care system. SETTING AND PARTICIPANTS: A total of 27,026 consecutive adults (>18 years old) with length of stay of at least 24 hours in a tertiary care center from January 1 to December 31, 2014. METHODS: Presence of delirium determined by routine delirium screening. Clinical characteristics, discharge destination, and mortality were collected. Calculation of odds ratios (ORs) with logistic regression with adjustment for age, sex, and Charlson comorbidity index (CCI). RESULTS: Delirium was detected in 19.7% of patients (5313 of 27,026), median age of delirious patients was 56 years (25-75 interquartile range = 37-70). The electronic health record (DSM-5-based) delirium algorithm correctly identified 93.3% of delirium diagnoses made by consultation-liaison psychiatrists. Across services, the odds of delirious patients returning home was significantly reduced [OR 0.12; confidence interval (CI) 0.10-0.13; P < .001]. Rather, these patients were transferred to acute rehabilitation (OR 4.15; CI 3.78-4.55; P < .001) or nursing homes (OR 4.12; CI 3.45-4.93; P < .001). Delirious patients had a significantly increased adjusted mortality risk (OR 30.0; CI 23.2-39.4; P < .001). CONCLUSIONS AND IMPLICATIONS: This study advances our understanding of the discharge destination across all services in adults admitted to a large hospital system. Delirium was associated with reduced odds of returning home, increased odds of discharge to a setting of higher dependency, and excess mortality independent of comorbidity, age, and sex. These findings emphasize the potentially devastating outcomes associated with delirium and highlight the need for timely diagnosis and hospital-wide management.

Delirium in trauma patients: a 1-year prospective cohort study of 2026 patients.

BACKGROUND: Delirium in trauma surgery is common, especially post-operatively, but medical characteristics, risk factors and residence post-discharge have not comprehensively been investigated in all trauma patients. METHODS: Over 1 year, 2026 trauma patients were prospectively screened for delirium with the following tools: Delirium Observation screening scale (DOS), Intensive Care Delirium Screening Checklist (ICDSC) and a DSM (Diagnostic and Statistical Manual)-5, nursing tool (ePA-AC) construct. Risk factors-predisposing und precipitating-for delirium were assessed via multiple regression analysis. RESULTS: Of 2026 trauma patients, 440 (21.7%) developed delirium, which was associated with an increased risk of assisted living (OR 6.42, CI 3.92-10.49), transfer to nursing home (OR 4.66, CI 3.29-6.6), rehabilitation (OR 3.96, CI 3.1-5.1), or death (OR 70.72, CI 22-227.64). Intensive care management (OR 18.62, CI 14.04-24.68), requirement of ventilation (OR 32.21, CI 21.27-48.78), or its duration (OR 67.22, CI 33.8-133.71) all increased the risk for developing delirium. Relevant predisposing risk factors were dementia (OR 50.92, CI 15.12-171.45), cardiac insufficiency (OR 11.76, CI 3.6-38.36), and polypharmacy (OR 5.9, CI 4.01-8.68).Relevant precipitating risk factors were brain edema (OR 40.53, CI 4.81-341.31), pneumonia (OR 39.66, CI 8.89-176.93) and cerebral inflammation (OR 21.74, CI 2.34-202.07). CONCLUSION: Delirium in trauma patients is associated with poor outcome as well as with intensive care management and various predisposing and/or precipitating factors. Three quarters of patients who had undergone delirium were not able to live independently at home any more.

Delirium: Prevalence and outcome in the very old in 27 medical departments during a one-year prospective study.

OBJECTIVE: The prevalence and effects of delirium in very old individuals aged ≥80 years have not yet been systematically evaluated. Therefore, this large single-center study of the one-year prevalence of delirium in 3,076 patients in 27 medical departments of the University Hospital of Zurich was conducted. METHODS: Patient scores on the Delirium Observation Screening scale, Intensive Care Delirium Screening Checklist, Diagnostic and Statistical Manual, 5th edition, and electronic Patient Assessment-Acute Care (nursing tool) resulted in the inclusion of 3,076 individuals in 27 departments. The prevalence rates were determined by simple logistic regressions, odds ratios (ORs), and confidence intervals. RESULTS: Of the 3,076 patients, 1,285 (41.8%) developed delirium. The prevalence rates in the 27 departments ranged from 15% in rheumatology (OR = 0.30) to 73% in intensive care (OR = 5.25). Delirious patients were more likely to have been admitted from long-term care facilities (OR = 2.26) or because of emergencies (OR = 2.24). The length of their hospital stay was twice as long as that for other patients. Some died before discharge (OR = 24.88), and others were discharged to nursing homes (OR = 2.96) or assisted living facilities (OR = 2.2). CONCLUSION: This is the largest study to date regarding the prevalence of delirium in patients aged ≥80 years and the medical characteristics of these patients. Almost two out of five patients developed delirium, with a high risk of loss of independence and mortality.

[Delirium Management in Palliative Care]. / Delirmanagement in der Palliative Care.

Delirium Management in Palliative Care Abstract. Delirium is one of the most common neuropsychiatric complications in patients with advanced incurable disease. End-of-life delirium is common but is often overlooked, undiagnosed or incorrectly diagnosed/untreated. Delirium should also be treated in a palliative situation - as far as possible - because persistent delirious states increase the patient's fragility, limit physical functionality and shorten the lifespan. In addition, acute states of confusion trigger high levels of distress in affected patients and their relatives, impair the quality of life and a dignified dying process. While hallucinations and visions at the end of life are interpreted as delirium in medicine and treated as such, this phenomenon is interpreted by philosophical and theological hermeneutics as a resource that can help patients and their relatives to reconcile with past life events and to deal with the process of dying. However, the occurrence of end-of-life visions as opposed to delirium has not yet been studied very much and requires more detailed exploration.

Predisposing and Precipitating Risk Factors for Delirium in Elderly Patients Admitted to a Cardiology Ward: An Observational Cohort Study in 1,042 Patients.

Aim: Although the risk factors for delirium in general medicine are well-established, their significance in cardiac diseases remains to be determined. Therefore, we evaluated the predisposing and precipitating risk factors in patients hospitalized with acute and chronic heart disease. Methods and Results: In this observational cohort study, 1,042 elderly patients (≥65 years) admitted to cardiology wards, 167 with and 875 without delirium, were included. The relevant sociodemographic and cardiac- and medical-related clusters were assessed by simple and multiple regression analyses and prediction models evaluating their association with delirium. The prevalence of delirium was 16.0%. The delirious patients were older (mean 80 vs. 76 years; p < 0.001) and more often institutionalized prior to admission (3.6 vs. 1.4%, p = 0.05), hospitalized twice as long (12 ± 10 days vs. 7 ± 7 days; p < 0.001), and discharged more often to nursing homes (4.8 vs. 0.6%, p < 0.001) or deceased (OR, 2.99; 95% CI, 1.53-5.85; p = 0.003). The most relevant risk factor was dementia (OR, 18.11; 95% CI, 5.77-56.83; p < 0.001), followed by history of stroke (OR, 6.61; 95% CI 1.35-32.44; p = 0.020), and pressure ulcers (OR, 3.62; 95% CI, 1.06-12.35; p = 0.040). The predicted probability for developing delirium was highest in patients with reduced mobility and institutionalization prior to admission (PP = 31.2%, p = 0.001). Of the cardiac diseases, only valvular heart disease (OR, 1.57; 95% CI, 1.01-2.44; p = 0.044) significantly predicted delirium. The patients undergoing cardiac interventions did not have higher rates of delirium (OR, 1.39; 95% CI 0.91-2.12; p = 0.124). Conclusion: In patients admitted to a cardiology ward, age-related functional and cognitive impairment, history of stroke, and pressure ulcers were the most relevant risk factors for delirium. With regards to specific cardiological factors, only valvular heart disease was associated with risk for delirium. Knowing these factors can help cardiologists to facilitate the early detection and management of delirium.

Economic Impact of Poststroke Delirium and Associated Risk Factors: Findings From a Prospective Cohort Study.

Background and Purpose: Delirium is a common severe complication of stroke. We aimed to determine the cost-of-illness and risk factors of poststroke delirium (PSD). Methods: This prospective single-center study included n=567 patients with acute stroke from a hospital-wide delirium cohort study and the Swiss Stroke Registry in 2014. Delirium was determined by Delirium Observation Screening Scale or Intensive Care Delirium Screening Checklist 3 times daily during the first 3 days of admission. Costs reflected the case-mix index and diagnosis-related groups from 2014 and were divided into nursing, physician, and total costs. Factors associated with PSD were assessed with multiple regression analysis. Partial correlations and quantile regression were performed to assess costs and other factors associated with PSD. Results: The incidence of PSD was 39.0% (221/567). Patients with delirium were older than non-PSD (median 76 versus 70 years; P<0.001), 52% male (115/221) versus 62% non-PSD (214/346) and hospitalized longer (mean 11.5 versus 9.3 days; P<0.001). Dementia was the most relevant predisposing factor for PSD (odds ratio, 16.02 [2.83­90.69], P=0.002). Moderate to severe stroke (National Institutes of Health Stroke Scale score 16­20) was the most relevant precipitating factor (odds ratio, 36.10 [8.15­159.79], P<0.001). PSD was a strong predictor for 3-month mortality (odds ratio, 15.11 [3.33­68.53], P<0.001). Nursing and total costs were nearly twice as high in PSD (P<0.001). There was a positive correlation between total costs and admission National Institutes of Health Stroke Scale (correlation coefficient, 0.491; P<0.001) and length of stay (correlation coefficient, 0.787; P<0.001) in all patients. Quantile regression revealed rising nursing and total costs associated with PSD, higher National Institutes of Health Stroke Scale, and longer hospital stay (all P<0.05). Conclusions: PSD was associated with greater stroke severity, prolonged hospitalization, and increased nursing and total costs. In patients with severe stroke, dementia, or seizures, PSD is anticipated, and additional costs are associated with hospitalization.

Risk Factors for Delirium Are Different in the Very Old: A Comparative One-Year Prospective Cohort Study of 5,831 Patients.

Background: In an ever-aging society, health care systems will be confronted with an increasing number of patients over 80 years ("the very old"). Currently, knowledge about and recommendations for delirium management are often based on studies in patients aged 60 to 65 years. It is not clear whether these findings apply to patients ≥80 years. Aim: Comparison of younger and older patients with delirium, especially regarding risk factors. Methods: In this prospective cohort study, within 1-year, 5,831 patients (18-80 years: n = 4,730; ≥80: n = 1,101) with delirium were enrolled. The diagnosis of delirium was based on the Delirium Observation screening scale (DOS), Intensive Care Delirium Screening Checklist (ICDSC) and a DSM (Diagnostic and Statistical Manual)-5 construct of nursing instrument. Sociodemographic trajectories, as well as the relevant predisposing and precipitating factors for delirium, were assessed via a multiple regression analysis. Results: The very old were more commonly admitted as emergencies (OR 1.42), had a greater mortality risk (OR 1.56) and displayed fewer precipitating risk factors for the development of a delirium, although the number of diagnoses were not different (p = 0.325). Predisposing factors were sufficient almost alone for the development of delirium in patients ≥ 80 years of age; in 18-80 years of age, additional precipitating factors had to occur to make a delirium possible. Conclusion: When relevant predisposing factors for delirium are apparent, patients over 80 years of age require comparatively few or no precipitating factors to develop delirium. This finding should be taken into account at hospitalization and may allow better treatment of delirium in the future.

Delirium is associated with an increased morbidity and in-hospital mortality in cancer patients: Results from a prospective cohort study.

OBJECTIVE: Delirium is a frequent complication in advanced cancer patients, among whom it is frequently underdiagnosed and inadequately treated. To date, evidence on risk factors and the prognostic impact of delirium on outcomes remains sparse in this patient population. METHOD: In this prospective observational cohort study at a single tertiary-care center, 1,350 cancer patients were enrolled. Simple and multiple logistic regression models were utilized to identify associations between predisposing and precipitating factors and delirium. Cox proportional-hazards models were used to estimate the effect of delirium on death rate. RESULTS: In our patient cohort, the prevalence of delirium was 34.3%. Delirium was associated inter alia with prolonged hospitalization, a doubling of care requirements, increased healthcare costs, increased need for institutionalization (OR 3.22), and increased mortality (OR 8.78). Predisposing factors for delirium were impaired activity (OR 10.82), frailty (OR 4.75); hearing (OR 2.23) and visual impairment (OR 1.89), chronic pneumonitis (OR 2.62), hypertension (OR 1.46), and renal insufficiency (OR 1.82). Precipitating factors were acute renal failure (OR 7.50), pressure sores (OR 3.78), pain (OR 2.86), and cystitis (OR 1.32). On multivariate Cox regression, delirium increased the mortality risk sixfold (HR 5.66). Age ≥ 65 years and comorbidities further doubled the mortality risk of delirious patients (HR 1.77; HR 2.05). SIGNIFICANCE OF RESULTS: Delirium is common in cancer patients and associated with increased morbidity and mortality. Systematically categorizing predisposing and precipitating factors might yield new strategies for preventing and managing delirium in cancer patients.

The prevalence rates and adversities of delirium: Too common and disadvantageous.

OBJECTIVE: The prevalence rates and adversities of delirium have not yet been systematically evaluated and are based on selected populations, limited sample sizes, and pooled studies. Therefore, this study assesses the prevalence rates and outcome of and odds ratios for managing services for delirium. METHODS: In this prospective cohort study, based on the Diagnostic and Statistical Manual (DSM) 5, the Delirium Observation Screening (DOS) scale, and the Intensive Care Delirium Screening Checklist (ICDSC) construct, 28,118 patients from 35 managing services were included, and the prevalence rates and adverse outcomes were determined by simple logistic regressions and their corresponding odds ratios (ORs). RESULTS: Delirious patients were older, admitted from institutions (OR 3.44-5.2), admitted as emergencies (OR 1.87), hospitalized twice longer, and discharged, transferred to institutions (OR 5.47-6.6) rather than home (OR 0.1), or deceased (OR 43.88). The rate of undiagnosed delirium was 84.2%. The highest prevalence rates were recorded in the intensive care units (47.1-84.2%, pooled 67.9%); in the majority of medical services, rates ranged from 20% to 40% (pooled 26.2%), except, at both ends, palliative care (55.9%), endocrinology (8%), and rheumatology (4.4%). Conversely, in surgery and its related services, prevalence rates were lower (pooled 13.1%), except for cardio- and neurosurgical services (53.3% and 46.4%); the lowest prevalence rate was recorded in obstetrics (2%). SIGNIFICANCE OF RESULTS: Delirium remains underdiagnosed, and novel screening approaches are required. Furthermore, this study identified the impact of delirium on patients, determined the prevalence rates for 32 services, and elucidated the association between individual services and delirium.

Death in delirious palliative-care patients occurs irrespective of age: A prospective, observational cohort study of 229 delirious palliative-care patients.

OBJECTIVES: Patients with terminal illness are at high risk of developing delirium, in particular, those with multiple predisposing and precipitating risk factors. Delirium in palliative care is largely under-researched, and few studies have systematically assessed key aspects of delirium in elderly, palliative-care patients. METHODS: In this prospective, observational cohort study at a tertiary care center, 229 delirious palliative-care patients stratified by age: <65 (N = 105) and ≥65 years (N = 124), were analyzed with logistic regression models to identify associations with respect to predisposing and precipitating factors. RESULTS: In 88% of the patients, the underlying diagnosis was cancer. Mortality rate and median time to death did not differ significantly between the two age groups. No inter-group differences were detected with respect to gender, care requirements, length of hospital stay, or medical costs. In patients ≥65 years, exclusively predisposing factors were relevant for delirium, including hearing impairment [odds ratio (OR) 3.64; confidence interval (CI) 1.90-6.99; P < 0.001], hypertension (OR 3.57; CI 1.84-6.92; P < 0.001), and chronic kidney disease (OR 4.84; CI 1.19-19.72; P = 0.028). In contrast, in patients <65 years, only precipitating factors were relevant for delirium, including cerebral edema (OR 0.02; CI 0.01-0.43; P = 0.012). SIGNIFICANCE OF RESULTS: The results of this study demonstrate that death in delirious palliative-care patients occurs irrespective of age. The multifactorial nature and adverse outcomes of delirium across all age in these patients require clinical recognition. Potentially reversible factors should be detected early to prevent or mitigate delirium and its poor survival outcomes.

Assessing delirium with nursing care instruments: Evaluation of the cognitive and associated domains.

OBJECTIVE: Nursing instruments have the potential for daily screening of delirium; however, they have not yet been evaluated. Therefore, after assessing the functional domains of the electronic Patient Assessment - Acute Care (ePA-AC), this study evaluates the cognitive and associated domains. METHODS: In this prospective cohort study in the intensive care unit, 277 patients were assessed and 118 patients were delirious. The impacts of delirium on the cognitive domains, consciousness and cognition, communication and interaction, in addition to respiration, pain, and wounds were determined with simple logistic regressions and their respective odds ratios (ORs). RESULTS: Delirium was associated with substantial impairment throughout the evaluated domains. Delirious patients were somnolent (OR 6), their orientation (OR 8.2-10.6) and ability to acquire knowledge (OR 5.5-11.6) were substantially impaired, they lost the competence to manage daily routines (OR 8.2-22.4), and their attention was compromised (OR 12.8). In addition, these patients received psychotropics (OR 3.8), were visually impaired (OR 1.8), unable to communicate their needs (OR 5.6-7.6), displayed reduced self-initiated activities (OR 6.5-6.9) and challenging behaviors (OR 6.2), as well as sleep-wake disturbances (OR 2.2-5), Furthermore, delirium was associated with mechanical ventilation, abdominal/thoracic injuries or operations (OR 4.2-4.4), and sensory perception impairment (OR 3.9-5.8). SIGNIFICANCE OF RESULTS: Delirium caused substantial impairment in cognitive and associated domains. In addition to the previously described functional impairments, these findings will aid the implementation of nursing instruments in delirium screening.

The prevalence rates and sequelae of delirium at age older than 90 years.

OBJECTIVE: Although age and pre-existent dementia are robust risk factors for developing delirium, evidence for patients older than 90 years is lacking. Therefore, this study assesses the delirium prevalence rates and sequelae in this age group. METHOD: Based on a Diagnostic and Statistical Manual (DSM)-5, Delirium Observation screening scale (DOS), and Intensive Care Delirium Screening Checklist (ICDSC) construct, in this prospective cohort study, the prevalence rates and sequelae of delirium were determined in 428 patients older than 90 years by simple logistic regressions and corresponding odds ratios (ORs). RESULTS: The overall prevalence delirium rate was 45.2%, with a wide range depending upon specialty: intermediate and intensive care services (83.1%), plastic surgery and palliative care (75%), neurology (72%), internal medicine (69%) vs. dermatology (26.5%), and angiology (14.5%). Delirium occurred irrespective of age and gender; however, pre-existent dementia was the strongest delirium predictor (OR 36.05). Delirious patients were less commonly admitted from home (OR 0.47) than from assisted living (OR 2.24), indicating functional impairment. These patients were more severely ill, as indicated by emergency (OR 3.25) vs. elective admission (OR 0.3), requirement for intensive care management (OR 2.12) and ventilation (OR 5.56-8.33). At discharge, one-third did not return home (OR 0.22) and almost half were transferred to assisted living (OR 2.63), or deceased (OR 47.76). SIGNIFICANCE OF RESULTS: At age older than 90 years, the prevalence and sequelae of delirium are substantial. In particular, functional impairment and pre-existent dementia predicted delirium and subsequently, the loss of independence and death were imminent.