Etiology Of Delirium Research Articles

From Traditional Typing to Intelligent Insights: A Narrative Review of Directions Toward Targeted Therapies in Delirium.

Delirium is a heterogeneous syndrome characterized by an acute change in level of consciousness that is associated with inattention and disorganized thinking. Delirium affects most critically ill patients and is associated with poor patient-oriented outcomes such as increased mortality, longer ICU and hospital length of stay, and worse long-term cognitive outcomes. The concept of delirium and its subtypes has existed since nearly the beginning of recorded medical literature, yet robust therapies have yet to be identified. Analogous to other critical illness syndromes, we suspect the lack of identified therapies stems from patient heterogeneity and prior subtyping efforts that do not capture the underlying etiology of delirium. The time has come to leverage machine learning approaches, such as supervised and unsupervised clustering, to identify clinical and pathophysiological distinct clusters of delirium that will likely respond differently to various interventions. We use sedation in the ICU as an example of how precision therapies can be applied to critically ill patients, highlighting the fact that while for some patients a sedative drug may cause delirium, in another cohort sedation is the specific treatment. Finally, we conclude with a proposition to move away from the term delirium, and rather focus on the treatable traits that may allow precision therapies to be tested.

Differences in metalloproteinases and their tissue inhibitors in the cerebrospinal fluid are associated with delirium

BackgroundThe aetiology of delirium is not known, but pre-existing cognitive impairment is a predisposing factor. Here we explore the associations between delirium and cerebrospinal fluid (CSF) levels of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs), proteins with important roles in both acute injury and chronic neurodegeneration.MethodsUsing a 13-plex Discovery Assay®, we quantified CSF levels of 9 MMPs and 4 TIMPs in 280 hip fracture patients (140 with delirium), 107 cognitively unimpaired individuals, and 111 patients with Alzheimer’s disease dementia. The two delirium-free control groups without acute trauma were included to unravel the effects of acute trauma (hip fracture), dementia, and delirium.ResultsHere we show that delirium is associated with higher levels of MMP-2, MMP-3, MMP-10, TIMP-1, and TIMP-2; a trend suggests lower levels of TIMP-4 are also associated with delirium. Most delirium patients had pre-existing dementia and low TIMP-4 is the only marker associated with delirium in adjusted analyses. MMP-2, MMP-12, and TIMP-1 levels are clearly higher in the hip fracture patients than in both control groups and several other MMP/TIMPs are impacted by acute trauma or dementia status.ConclusionsSeveral CSF MMP/TIMPs are significantly associated with delirium in hip fracture patients, but alterations in most of these MMP/TIMPs could likely be explained by acute trauma and/or pre-fracture dementia. Low levels of TIMP-4 appear to be directly associated with delirium, and the role of this marker in delirium pathophysiology should be further explored.

Postoperative Delirium and the Older Adult: Untangling the Confusion.

Postoperative delirium is one of the most prevalent postoperative complications, affecting mostly older adults. Its incidence is expected to rise because of surgical advances, shifting demographics, and increased life expectancy. Although an acute alteration in brain function, postoperative delirium is associated with adverse outcomes, including progressive cognitive decline and dementia, that place significant burdens on patients' lives and healthcare systems. This has prompted efforts to understand the mechanisms of postoperative delirium to provide effective prevention and treatment. There are multiple mechanisms involved in the etiology of postoperative delirium that share similarities with the physiological changes associated with the aging brain. In addition, older patients often have multiple comorbidities including increased cognitive impairment that is also implicated in the genesis of delirium. These tangled connections pinpointed a shift toward creation of a holistic model of the pathophysiology of postoperative delirium. Scientific advancements integrating clinical risk factors, possible postoperative delirium biomarkers, genetic features, digital platforms, and other biotechnical and information technological innovations, will become available in the near future. Advances in artificial intelligence, for example, will aggregate cognitive testing platforms with patient-specific postoperative delirium risk stratification studies, panels of serum and cerebrospinal fluid molecules, electroencephalogram signatures, and gut microbiome features, along with the integration of novel polygenetic variants of sleep and cognition. These advances will allow for the enrollment of high-risk patients into prevention programs and help uncover new pharmacologic targets.

Ekbom síndrome (Parasitosis delirium): Cocaine Use vs. Psychotic Depression. A case report

IntroductionParasitosis delirium represents a rare mono-symptomatic psychosis characterized by the delirious firm belief of the patient, against all evidence, of being infested by cutaneous parasites. The syndrome affects in particular middle-aged women, and can be the single manifestation of psychological uneasiness or represent one of the aspects of a more complex psychiatric case, compromising almost totally any normal daily work and/or social activity. It is often accompanied by a refusal to seek psychiatric care. This condition can be associated with various underlying causes, including substance use disorders and psychotic depression. Understanding the differences and similarities between delirium of infestation in the context of cocaine use and psychotic depression is crucial for accurate diagnosis and effective treatment.ObjectivesThis study aims to compare and contrast the clinical features, etiology, and treatment approaches of delirium of infestation in individuals with cocaine use and those with psychotic depression. By examining these two distinct populations, we can gain insights into the unique challenges and considerations associated with each condition.MethodsA case report of a 44-year-old woman with delirium of parasitosis, depressive symptoms and cocaine use in the last three days. Also a comprehensive literature review using the PubMed database to identify relevant clinical articles on delirium of infestation, cocaine use, and psychotic depression.Results Cocaine use and psychotic depression can both cause delirium of infestation. Cocaine-induced delirium is characterized by agitation, paranoia, and delusions of infestation. Psychotic depression is characterized by a depressed mood, delusions, and hallucinations. Delusions of infestation are a common feature of bothconditions. However, the underlying mechanisms and treatment approaches differ. Cocaine-induced delirium is primarily associated with the acute effects of cocaine on the central nervous system, while psychotic depression involves a complex interplay of biological, psychological, and environmental factors. Treatment for cocaine-induced delirium involves addressing the underlying cocaine use, while treatment for psychotic depression involves antidepressant and antipsychotic medications. Otherwise, Anti-Parkinson drugs were most frequently associated with delusional infestationConclusionsDelirium of infestation can occur in individuals with cocaine use and those with psychotic depression, albeit with different etiologies. Clinicians should consider the underlying cause when diagnosing and treating patients with this condition. Further research is needed to explore the specific neurobiological mechanisms and optimal treatment strategies for delirium of infestation in these distinct populations.Disclosure of InterestNone Declared

Knowledge of Delirium Among ICU Nursing Staff: A Cross-sectional Study

Background: Delirium is a reversible state that, if ignored, can result in increased morbidity and mortality. Studies from across the world have shown that nurses’ knowledge regarding delirium is inadequate. This study is one of the very few Indian studies addressing this issue. The study aims to infer an intensive care unit (ICU) nurse’s knowledge regarding delirium. Materials and Methods: This is a descriptive study carried out in the ICUs of a multispecialty general hospital. A convenient sample of 220 nurses was recruited after obtaining written informed consent. Knowledge regarding delirium was ascertained using the Delirium Knowledge Questionnaire; this, along with the sociodemographic variables, was circulated as Google Forms through WhatsApp groups. Data were analyzed using Statistical Package for the Social Sciences (SPSS) version 26, and results were presented as means and percentages. Results: The present study reveals that out of 211 nurses 130 (61.6%) had an average knowledge about delirium. Out of the 211 nurses 108 (51.2%) had average knowledge about clinical features of delirium and 105(49.8%) had average knowledge about etiology of delirium. More than half of the nurses (53.1%) had awareness regarding the medical management of delirium. In the domain of knowledge regarding non-medical management, 81 (38.4%) had excellent knowledge and 114 (54%) respondents had average knowledge regarding the prevention of delirium. Conclusion: The study calls for the need to provide educational interventions to the nursing staff for prevention, prompt recognition, and treatment of delirium.

Does the Etiology, Phenomenology and Motor Subtype of Delirium Differ When It Occurs in Patients With An Underlying Dementia?: A Multi-Site, International Study.

To compare the etiology, phenomenology and motor subtype of delirium in patients with and without an underlying dementia. A combined dataset (n = 992) was collated from two databases of older adults (>65 years) from liaison psychiatry and palliative care populations in Ireland and India. Phenomenology and severity of delirium were analysed using the Delirium Symptom Rating Scale Revised (DRS-R98) and contributory etiologies for the delirium groups were ascertained using the Delirium Etiology Checklist (DEC). Delirium motor subtype was documented using the abbreviated version of the Delirium Motor Subtype Scale (DMSS4). Delirium superimposed on dementia (DSD) showed greater impairment in short term memory, long term memory and visuospatial ability than the delirium group but showed significantly less perceptual disturbance, temporal onset and fluctuation. Systemic infection, cerebrovascular and other Central nervous system etiology were associated with DSD while metabolic disturbance, organ insufficiency and intracranial neoplasm were associated with the delirium only group. The etiology and phenomenology of delirium differs when it occurs in the patient with an underlying dementia. We discuss the implications in terms of identification and management of this complex condition.

Stuck in the Dark: No Association between Light, Sound, and Delirium in the PICU

AbstractThe purpose of this study was to evaluate the association between sound and light variables and development of delirium in pediatric intensive care unit (PICU) patients within the subsequent 3 days. Light and sound were continuously measured, and patient-specific data were collected daily. Outcomes included presence of delirium, determined by Cornell Assessment of Pediatric Delirium (CAPD) score ≥ 9 on at least 1 day, and development of delirium in the subsequent 3 days. One hundred and forty-two patients were enrolled, totaling 896 study days. Delirium prevalence was 31%. Neurologic diagnosis, younger age, longer PICU stay, restraints, benzodiazepines, opiate infusion, and dexmedetomidine were associated with delirium. Nighttime sound peaks (>70 and >80 dB) were not associated with delirium (p = 0.94 and 0.36, respectively). Light intensity during midday hours (12:00, 1:00, 2:00 pm) was not associated with the development of delirium (p=0.93, 0.81, 0.83, respectively), nor was maximum light at night, difference between maximum daytime and nighttime light, or between maximum and minimum daytime light (p = 0.15, 0.46, and 0.96, respectively). When adjusting for covariables, none of the sound or light variables was associated with delirium. Despite increasing awareness of pediatric delirium, data surrounding modifiable risk factors and concrete treatment strategies are lacking. We found no significant association between light or sound and development of delirium in PICU patients. However, there was little difference between daytime and nighttime light and sound, which may have impacted findings. As the etiology of delirium is multifactorial and potentially different for individual patients, targeted light/dark cycles warrant further study as they relate to delirium and critical illness.

Severity, etiology, and outcome of delirium in indoor patients referred to consultation-liaison psychiatry

Severity, etiology, and outcome of delirium in indoor patients referred to consultation-liaison psychiatry

Diagnostic yield of CT head in delirium and altered mental status-A systematic review and meta-analysis.

CT head is commonly performed in the setting of delirium and altered mental status (AMS), with variable yield. We aimed to evaluate the yield of CT head in hospitalized patients with delirium and/or AMS across a variety of clinical settings and identify factors associated with abnormal imaging. We included studies in adult hospitalized patients, admitted to the emergency department (ED) and inpatient medical unit (grouped together) or the intensive care unit (ICU). Patients had a diagnosis of delirium/AMS and underwent a CT head that was classified as abnormal or not. We searched Medline, Embase and other databases (informed by PRISMA guidelines) from inception until November 11, 2021. Studies that were exclusively performed in patients with trauma or a fall were excluded. A meta-analysis of proportions was performed; the pooled proportion of abnormal CTs was estimated using a random effects model. Heterogeneity was determined via the I2 statistic. Factors associated with an abnormal CT head were summarized qualitatively. Forty-six studies were included for analysis. The overall yield of CT head in the inpatient/ED was 13% (95% CI: 10.2%-15.9%) and in ICU was 17.4% (95% CI: 10%-26.3%), with considerable heterogeneity (I2 96% and 98% respectively). Heterogeneity was partly explained after accounting for study region, publication year, and representativeness of the target population. Yield of CT head diminished after year 2000 (19.8% vs. 11.1%) and varied widely depending on geographical region (8.4%-25.9%). The presence of focal neurological deficits was a consistent factor that increased yield. Use of CT head to diagnose the etiology of delirium and AMS varied widely and yield has declined. Guidelines and clinical decision support tools could increase the appropriate use of CT head in the diagnostic etiology of delirium/AMS.

Haloperidol Versus Atypical Antipsychotics for Treating Delirium in Intensive Care Unit Patients: A Systematic Review.

Delirium is a severe and variable neuropsychiatric illness that causes cognitive and behavioral problems as well as abrupt impairment in consciousness and focus.Due to the complex, dynamic, and multifaceted interactions between several risk factors, the etiology of delirium is unclear. Although its efficacy has not been thoroughly studied, haloperidol, a common antipsychotic medicine, is frequently used to prevent delirium in critically ill patients. When evaluating the atypical antipsychotic response rates for treating delirium, only a few trials have taken age into account. Articles were searched for from PubMed, PubMed Central (PMC), and Science Direct, and reviewed systematically. A complete 225 articles were identified after applying the search strategy to these databases. Out of these, 12 were finalized for review. We reviewed the efficacy and safety of haloperidol with atypical antipsychotics for treating delirium in intensive care unit patients.

Delirium in a patient with myocardial infarction

Delirium is a predictor of poor outcome in both myocardial infarction and other nosologies. Despite the growing interest in this problem, no effective methods for prediction, prevention, and treatment of delirium have been found. This literature review highlights the current ideas about delirium etiology, pathogenesis, approaches to prevention and treatment, and features of delirium in patients with myocardial infarction. The review presents the analysis of clinical trials and meta-analyses with the identification of causes for clinical trials failures and the search for future promising directions of research focusing on this syndrome.

Delirium in oncological palliative care and clinical cardiology units: A comparative analysis.

The aim of this study was to compare the sociodemographic and clinical characteristics of delirium in patients treated in a clinical cardiology unit (CCU) and an oncological palliative care unit (OPCU) at a high-complexity institution. Delirium is a neuropsychiatric syndrome with multicausal etiology, associated with increased morbidity and mortality. This was a cross-sectional, analytical observational study. CCU and OPCU patients were evaluated for 480 days. The diagnosis was made according to DSM-V. Sociodemographic characteristics, the Karnofsky index, and the Charlson index were evaluated. Possible etiologies were verified. Severity was assessed with the Delirium Severity Scale (DRS-R98). A total of 1,986 patients were evaluated, 205 were eligible, and 110 were included in the study (CCU: 61, OPCU: 49). Delirium prevalence was 11.35% in the CCU and 9.87% in the OPCU. CCU patients were 12 years older (p < 0.03) and a history of dementia (41 vs. 8.2%; p < 0.001). Organ failure was the most frequent etiology of delirium in the CCU (41.0%), and in the OPCU, the etiologies were neoplasms (28.6%), side effect of medication (22.4%), and infections (2.5%). Differences were found in the clinical characteristics of delirium evaluated by DRS-R98, with the condition being more severe and with a higher frequency of psychotic symptoms in OPCU patients. Delirium was a common condition in hospitalized patients in the CCU and the OPCU. The clinical characteristics were similar in both groups; however, significant differences were found in OPCU patients in terms of age, personal history of dementia, and opioid use, as well as the severity of delirium and a greater association with psychotic symptoms. These findings have implications for the early implementation of diagnostic and therapeutic strategies.

E4BP4 Coordinates Circadian Control of Cognition in Delirium.

Improved understanding of the etiologies of delirium, a common and severe neuropsychiatric syndrome, would facilitate the disease prevention and treatment. Here, the authors invesitgate the role of circadian rhythms in the pathogenesis of delirium. They observe perturbance of circadian rhythms in mouse models of delirium and disrupted clock gene expression in patients with delirium. In turn, physiological and genetic circadian disruptions sensitize mice to delirium with aggravated cognitive impairment. Likewise, global deletion of E4bp4 (E4 promoter‐binding protein), a clock gene markedly altered in delirium conditions, results in exacerbated delirium‐associated cognitive decline. Cognitive decline in delirium models is attributed to microglial activation and impaired long‐term potentiation in the hippocampus. Single‐cell RNA‐sequencing reveals microglia as the regulatory target of E4bp4. E4bp4 restrains microglial activation via inhibiting the ERK1/2 signaling pathway. Supporting this, mice lacking in microglial E4bp4 are delirious prone, whereas mice with E4bp4 specifically deleted in hippocampal CA1 neurons have a normal phenotype. Mechanistically, E4bp4 inhibits ERK1/2 signaling by trans‐repressing Mapk1/3 (genes encoding ERK1/2) via direct binding to a D‐box element in the promoter region. These findings define a causal role of clock dysfunction in delirium development and indicate E4bp4 as a regulator of cognition at the crosstalk between circadian clock and delirium.

Screening for delirium and dementia in older hospitalised adults in Zambia

Delirium prevalence and aetiology in older people in hospital or community settings in sub-Saharan Africa (SSA) is largely unknown. Cognitive screening tools designed for high-income countries (HICs) may be inappropriate due to cultural and educational differences, and delirium-specific measures lack validation in this context. The ‘Identification and Intervention for Dementia in Elderly Africans’ (IDEA) screen is a low-literacy tool developed and validated for dementia and delirium screening in Tanzania and Nigeria.This study aims to determine the prevalence and aetiology of delirium and dementia in older hospitalised patients in Zambia and to assess the utility of the IDEA screen for identification of major cognitive impairment in this setting.This was a blinded 4-month validation study which took place February–June 2015. Consecutive inpatient admissions of a rural mission hospital aged ≥60 years were administered the IDEA screen onadmission. Individuals were evaluated for dementia or delirium based on clinical examination, notes review and the Confusion Assessment Method. Delirium aetiological factors were recorded and classified (infectious/non-infectious).Of 136 patients recruited, dementia, delirium and major cognitive impairment were identified in 37 (27.2%), 45 (33.1%) and 62 (45.6%) respectively. Diagnostic accuracy of the IDEA screen for dementia and delirium was 0.661–0.795 (AUROC). Of those with delirium, 18 (40%) were classified infectious and 26 (57.8%) were classified non-infectious aetiologies.Dementia and delirium prevalence in older Zambian inpatients is comparable tohigh-income countries. The IDEA screen ispotentially clinically useful in this setting though diagnostic accuracy was lower than in initial validation studies. Non-infectious diseases are more highly represented amongst delirium precipitants than anticipated.

Association between nonpharmacological strategies and delirium in the intensive care unit.

Several nonpharmacological strategies for the prevention and treatment of delirium have been increasingly used because the aetiology of delirium is multifactorial. To verify the association between nonpharmacological strategies (presence of companion, mobilization, absence of physical restraint and natural light) and the occurrence of delirium, and to identify risk factors for delirium in intensive care unit (ICU) patients. The study was conducted in a Brazilian medical and surgical ICU. The sample included patients older than 18 years with length of ICU stay greater than 24 h and without delirium on admission. Delirium was identified by applying the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). The association between the variables and delirium was analysed using Mann-Whitney and chi-square tests, and multivariate logistic regression to identify the predictive factors. Of the 356 patients, 64 (18%) had delirium. The presence of a companion, mobilization, and physical restraint were associated with delirium, and the first two were identified as protective factors. That is, the odds of delirium decreased by 88% when a companion was present and by 95% when the patient was mobilized. The risk factors of delirium were length of ICU stay and age. The presence of a companion and patient mobilization were identified as protective factors against delirium, highlighting their importance as preventive actions, especially in patients with a higher risk of developing this disorder. The findings regarding physical restraint can also be considered evidence indicating the need for careful use of this measure in clinical practice until evidence of its relationship with delirium is confirmed. The implementation of strategies such as early mobilization, presence of a companion and careful assessment for the use of physical restraint by the multidisciplinary team can help control the occurrence of delirium in the ICU.

Characteristics and pharmacological treatment options of delirium patients treated at Sanglah Central General Hospital

Delirium is a syndrome characterized by disturbances of consciousness and cognition that occur acutely and fluctuate. Delirium can be caused by general medical conditions, drug users, sensory disturbances, polypharmacy, etc. The etiology of delirium is diverse and non-specific. The preference of pharmacological therapy in delirium is still a debate. Descriptive research with the retrospective cross-sectional method, using secondary data in medical records at the Sanglah Central General Hospital Denpasar for the period January 1, 2020, to December 31, 2020. Patients who were consulted were 166 people, with sex 57 people (34.3%) and 109 women (65.7%). The incidence of delirium in adults (20-59 years old) and elderly (age 60 years) is the highest with 51.2% and 45.1% respectively. One-third of 45 people (37.2%) had overlapping dementia. Most of the 142 people (85.5%) were experiencing significant life stress. The most common type of delirium was hyperactive delirium (74%). The underlying disease of delirium varies such as the cause of infection (24.1%), intracranial process (19%), malignancy 18.1%, cardiovascular (10.1%), endocrine disorders,(7.8%), kidney disorders (6%), and others in small percentages.

Psychiatric management of Patients in intensive care units.

Psychiatric management of Patients in intensive care units.

75.2 NEUROBIOLOGY OF DELIRIUM

The goal of this session is to describe the current understanding of the neurobiology of delirium with a specific focus on children. The presentation will include proposed mechanisms of delirium and discuss clinical evaluation and management in the pediatric population. A literature review will examine the neurobiology of pediatric delirium with a discussion of its clinical application. Adult literature will be included to incorporate our evolving understanding of the neuroscience of delirium. A vignette will be presented to guide the audience through clinical screening, assessment, and management, demonstrating the application of understanding of neurobiology in a critically ill child. The review will address the variability of clinical presentation and clinical management depending on the subtype of delirium and the underlying etiology of delirium, and it will highlight the importance of structured monitoring of symptoms and response to interventions. Pediatric delirium is a syndrome representing complications from multiple critical care etiologies. The child and adolescent psychiatrist must consider the various pathways to disruption of the brain’s ability to attend to and process the environment. Delirium is, by definition, a fluctuating level of consciousness, which makes careful assessment and ongoing tracking of symptoms critical in order to understand the clinical options to manage the syndrome. The fluctuations complicate the ability to distinguish delirium and catatonia; treatment varies depending on the syndrome, and the neurobiology of the 2 syndromes may lead to challenges in treatment when comorbid. The vignette will demonstrate the application of clinical understanding of delirium for effective management. Pediatric delirium is a syndrome resulting from critical illness in children. Studies have identified significant mortality as well as long-term morbidity when not adequately managed. Delirium and catatonia may co-occur, emphasizing the importance of understanding the neurobiology of delirium. Child and adolescent psychiatrists can benefit from understanding the acute assessment and management of delirium as well as the long-term outcomes potentially seen in outpatient practices.

Related Factors and Treatment of Postoperative Delirium in Old Adult Patients: An Integrative Review.

“Postoperative delirium” is defined as delirium occurring in the hospital up to one week after a procedure or before discharge (whichever occurs first) that meets the DSM-5 diagnostic criteria. Objectives: To describe the risk factors related to this pathology and identify effective non-pharmacological forms of treatment. An integrative review of the available literature was performed. The search results considered included all quantitative studies published between 2011 and 2019 in both English and Spanish. A total of 117 studies were selected. Advanced age was identified as the principal risk factor for postoperative delirium. Nursing interventions appear to be the key to preventing or reducing the seriousness of delirium after an anaesthetic episode. The aetiology of postoperative delirium remains unknown, and no treatment exists to eliminate this pathology. The role of nursing staff is fundamental in the prevention, diagnosis, and management of the pathology.

Etiologies of Delirium in Consecutive COVID-19 Inpatients and the Relationship Between Severity of Delirium and COVID-19 in a Prospective Study With Follow-Up.

The investigators aimed to describe delirium etiologies and clinical characteristics, as well as the relationship between COVID-19 and delirium severities, at baseline and follow-up after delirium improvement among patients with SARS-CoV-2 infection. A longitudinal study of 20 consecutive critically ill, delirious COVID-19 inpatients, assessed with the Charlson Comorbidity Index-Short Form (CCI-SF), COVID-19 Clinical Severity Scale (CCSS), Delirium Etiology Checklist, Delirium Motor Subtype Scale-4, and Delirium Diagnostic Tool-Provisional (DDT-Pro), was conducted. Correlational analysis of delirium severity (DDT-Pro) with each measure of clinical severity (CCI-SF and CCSS) and comparison of baseline DDT-Pro scores between patients who were living and those who were deceased at follow-up were conducted. Participants were 50-90 years old (male, 75%; hypertension, 60%). The prevalence of preexisting medical comorbidities (CCI-SF) was low and not correlated with delirium severity (p=0.193). Eighteen patients were on mechanical or high-flow noninvasive ventilation at baseline in the intensive care unit (ICU; CCSS scores 2-4). Delirium severity (DDT-Pro scores 0-6) correlated with COVID-19 severity (0.459, p=0.021). Delirium motor subtype was hyperactive in 75% of patients. There were three to four etiologies for delirium in each patient, most commonly organ insufficiency (100%), systemic infection (100%), and metabolic and endocrine disturbances (95%). The baseline DDT-Pro score was ≤4 for five (25%) patients who died before the final assessment, with a trend of being lower than that for survivors (χ2=3.398, p=0.065). Among inpatients with COVID-19, at least three different etiological categories were identified for delirium. ICU staff treating patients with severe cases of COVID-19 should anticipate a greater severity of delirium. Although multivariate analyses with larger study samples are needed, more severe delirium may herald greater risk of death among COVID-19 patients.