Plasma biomarkers of inflammation, coagulation, and brain injury as predictors of delirium duration in older hospitalized patients

SARS-CoV-2 infection is associated with an increase in new diagnoses of schizophrenia spectrum and psychotic disorder: A study using the US national COVID cohort collaborative (N3C)

Amid the ongoing global repercussions of SARS-CoV-2, it is crucial to comprehend its potential long-term psychiatric effects. Several recent studies have suggested a link between COVID-19 and subsequent mental health disorders. Our investigation joins this exploration, concentrating on Schizophrenia Spectrum and Psychotic Disorders (SSPD). Different from other studies, we took acute respiratory distress syndrome (ARDS) and COVID-19 lab-negative cohorts as control groups to accurately gauge the impact of COVID-19 on SSPD. Data from 19,344,698 patients, sourced from the N3C Data Enclave platform, were methodically filtered to create propensity matched cohorts: ARDS (n = 222,337), COVID-19 positive (n = 219,264), and COVID-19 negative (n = 213,183). We systematically analyzed the hazard rate of new-onset SSPD across three distinct time intervals: 0-21 days, 22-90 days, and beyond 90 days post-infection. COVID-19 positive patients consistently exhibited a heightened hazard ratio (HR) across all intervals [0-21 days (HR: 4.6; CI: 3.7-5.7), 22-90 days (HR: 2.9; CI: 2.3 -3.8), beyond 90 days (HR: 1.7; CI: 1.5-1.)]. These are notably higher than both ARDS and COVID-19 lab-negative patients. Validations using various tests, including the Cochran Mantel Haenszel Test, Wald Test, and Log-rank Test confirmed these associations. Intriguingly, our data indicated that younger individuals face a heightened risk of SSPD after contracting COVID-19, a trend not observed in the ARDS and COVID-19 negative groups. These results, aligned with the known neurotropism of SARS-CoV-2 and earlier studies, accentuate the need for vigilant psychiatric assessment and support in the era of Long-COVID, especially among younger populations.

Serum proteomic analysis in esophagectomy patients with postoperative delirium: A case-control study

BACKGROUND

Postoperative delirium occurs in up to 80% of patients undergoing esophagectomy. We performed an exploratory proteomic analysis to identify protein pathways that may be associated with delirium post-esophagectomy.

OBJECTIVES

Identify proteins associated with delirium and delirium severity in a younger and higher-risk surgical population.

METHODS

We performed a case-control study using blood samples collected from patients enrolled in a negative, randomized, double-blind clinical trial. English speaking adults aged 18 years or older, undergoing esophagectomy, who had blood samples obtained were included. Cases were defined by a positive delirium screen after surgery while controls were patients with negative delirium assessments. Delirium was assessed using Richmond Agitation Sedation Scale and Confusion Assessment Method for the Intensive Care Unit, and delirium severity was assessed by Delirium Rating Scale-Revised-98. Blood samples were collected pre-operatively and on post-operative day 1, and discovery proteomic analysis was performed. Between-group differences in median abundance ratios were reported using Wilcoxon-Mann-Whitney Odds (WMWodds1) test.

RESULTS

52 (26 cases, 26 controls) patients were included in the study with a mean age of 64 (SD 9.6) years, 1.9% were females and 25% were African American. The median duration of delirium was 1 day (IQR: 1-2), and the median delirium/coma duration was 2.5 days (IQR: 2-4). Two proteins with greater relative abundance ratio in patients with delirium were: Coagulation factor IX (WMWodds: 1.89 95%CI: 1.0-4.2) and mannosyl-oligosaccharide 1,2-alpha-mannosidase (WMWodds: 2.4 95%CI: 1.03-9.9). Protein abundance ratios associated with mean delirium severity at postoperative day 1 were Complement C2 (Spearman rs = -0.31, 95%CI [-0.55, -0.02]) and Mannosyl-oligosaccharide 1,2-alpha-mannosidase (rs = 0.61, 95%CI = [0.29, 0.81]).

CONCLUSIONS

We identified changes in proteins associated with coagulation, inflammation, and protein handling; larger, follow-up studies are needed to confirm our hypothesis-generating findings.

SARS-CoV-2 Infection is Associated with an Increase in New Diagnoses of Schizophrenia Spectrum and Psychotic Disorder: A Study Using the US National COVID Cohort Collaborative (N3C)

Amid the ongoing global repercussions of SARS-CoV-2, it's crucial to comprehend its potential long-term psychiatric effects. Several recent studies have suggested a link between COVID-19 and subsequent mental health disorders. Our investigation joins this exploration, concentrating on Schizophrenia Spectrum and Psychotic Disorders (SSPD). Different from other studies, we took acute respiratory distress syndrome (ARDS) and COVID-19 lab negative cohorts as control groups to accurately gauge the impact of COVID-19 on SSPD. Data from 19,344,698 patients, sourced from the N3C Data Enclave platform, were methodically filtered to create propensity matched cohorts: ARDS (n = 222,337), COVID-positive (n = 219,264), and COVID-negative (n = 213,183). We systematically analyzed the hazard rate of new-onset SSPD across three distinct time intervals: 0-21 days, 22-90 days, and beyond 90 days post-infection. COVID-19 positive patients consistently exhibited a heightened hazard ratio (HR) across all intervals [0-21 days (HR: 4.6; CI: 3.7-5.7), 22-90 days (HR: 2.9; CI: 2.3 -3.8), beyond 90 days (HR: 1.7; CI: 1.5-1.)]. These are notably higher than both ARDS and COVID-19 lab-negative patients. Validations using various tests, including the Cochran Mantel Haenszel Test, Wald Test, and Log-rank Test confirmed these associations. Intriguingly, our data indicated that younger individuals face a heightened risk of SSPD after contracting COVID-19, a trend not observed in the ARDS and COVID-negative groups. These results, aligned with the known neurotropism of SARS-CoV-2 and earlier studies, accentuate the need for vigilant psychiatric assessment and support in the era of Long-COVID, especially among younger populations.

Inclusion of frailty improved performance of delirium prediction for elderly patients in the cardiac intensive care unit (D-FRAIL): A prospective derivation and external validation study

BACKGROUND

The elderly patients admitted to cardiac intensive care unit (CICU) are at relatively high risk for developing delirium. A simple and reliable predictive model can benefit them from early recognition of delirium followed by timely and appropriate preventive strategies.

OBJECTIVE

To explore the role of frailty in delirium prediction and develop and validate a delirium predictive model including frailty for elderly patients in CICU.

DESIGN

A prospective, observational cohort study.

SETTINGS

CICU at China-Japan Friendship Hospital from March 1, 2022 to August 25, 2022 (derivation cohort); CICU at Beijing Anzhen Hospital affiliated to Capital Medical University from March 14, 2023 to May 8, 2023 (external validation cohort).

PARTICIPANTS

A total of 236 and 90 participants were enrolled in the derivation and external validation cohorts, respectively. Participants in the derivation cohort were assigned into either the delirium (n = 70) or non-delirium group (n = 166) based on the occurrence of delirium.

METHODS

The simplified Chinese version of the Confusion Assessment Method for the Diagnosis of Delirium in the Intensive Care Unit was used to assess delirium twice a day at 8:00-10:00 and 18:00-20:00 until the onset of delirium or discharge from the CICU. Frailty was assessed using the FRAIL scale during the first 24 h in the CICU. Other possible risk factors were collected prospectively through patient interviews and medical records review. After processing missing data via multiple imputations, univariate analysis and bootstrapped forward stepwise logistic regression were performed to select optimal predictors and develop the models. The models were internally validated using bootstrapping and evaluated comprehensively via discrimination, calibration, and clinical utility in both the derivation and external validation cohorts.

RESULTS

The study developed D-FRAIL predictive model using FRAIL score, hearing impairment, Acute Physiology and Chronic Health Evaluation-II score, and fibrinogen. The area under the receiver operating characteristic curve (AUC) was 0.937 (95% confidence interval [CI]: 0.907-0.967) and 0.889 (95%CI: 0.840-0.938) even after bootstrapping in the derivation cohort. Inclusion of frailty was demonstrated to improve the model performance greatly with the AUC increased from 0.851 to 0.937 (p < 0.001). In the external validation cohort, the AUC of D-FRAIL model was 0.866 (95%CI: 0.782-0.907). Calibration plots and decision curve analysis suggested good calibration and clinical utility of the D-FRAIL model in both the derivation and external validation cohorts.

CONCLUSIONS

For elderly patients in the CICU, FRAIL score is an independent delirium predictor and the D-FRAIL model demonstrates superior performance in predicting delirium.

Neuroinflammation: The central enabler of postoperative cognitive dysfunction

The proportion of advanced age patients undergoing surgical procedures is on the rise owing to advancements in surgical and anesthesia technologies as well as an overall aging population. As a complication of anesthesia and surgery, older patients frequently suffer from postoperative cognitive dysfunction (POCD), which may persist for weeks, months or even longer. POCD is a complex pathological process involving multiple pathogenic factors, and its mechanism is yet unclear. Potential theories include inflammation, deposition of pathogenic proteins, imbalance of neurotransmitters, and chronic stress. The identification, prevention, and treatment of POCD are still in the exploratory stages owing to the absence of standardized diagnostic criteria. Undoubtedly, comprehending the development of POCD remains crucial in overcoming the illness. Neuroinflammation is the leading hypothesis and a crucial component of the pathological network of POCD and may have complex interactions with other mechanisms. In this review, we discuss the possible ways in which surgery and anesthesia cause neuroinflammation and investigate the connection between neuroinflammation and the development of POCD. Understanding these mechanisms may likely ensure that future treatment options of POCD are more effective.

Extracellular Vesicles as Possible Plasma Markers and Mediators in Patients with Sepsis-Associated Delirium-A Pilot Study

Patients with sepsis-associated delirium (SAD) show severe neurological impairment, often require an intensive care unit (ICU) stay and have a high risk of mortality. Hence, useful biomarkers for early detection of SAD are urgently needed. Extracellular vesicles (EVs) and their cargo are known to maintain normal physiology but also have been linked to numerous disease states. Here, we sought to identify differentially expressed proteins in plasma EVs from SAD patients as potential biomarkers for SAD. Plasma EVs from 11 SAD patients and 11 age-matched septic patients without delirium (non-SAD) were isolated by differential centrifugation, characterized by nanoparticle tracking analysis, transmission electron microscopy and Western blot analysis. Differential EV protein expression was determined by mass spectrometry and the resulting proteomes were characterized by Gene Ontology term and between-group statistics. As preliminary results because of the small group size, five distinct proteins showed significantly different expression pattern between SAD and non-SAD patients (p ≤ 0.05). In SAD patients, upregulated proteins included paraoxonase-1 (PON1), thrombospondin 1 (THBS1), and full fibrinogen gamma chain (FGG), whereas downregulated proteins comprised immunoglobulin (IgHV3) and complement subcomponent (C1QC). Thus, plasma EVs of SAD patients show significant changes in the expression of distinct proteins involved in immune system regulation and blood coagulation as well as in lipid metabolism in this pilot study. They might be a potential indicator for to the pathogenesis of SAD and thus warrant further examination as potential biomarkers, but further research is needed to expand on these findings in longitudinal study designs with larger samples and comprehensive polymodal data collection.

Association Between Gut Microbiota and Delirium in Acutely Ill Older Adults

Our aim was to investigate the association between gut microbiota and delirium occurrence in acutely ill older adults. We included 133 participants 65+ years consecutively admitted to the emergency department of a tertiary university hospital, between September 2019 and March 2020. We excluded candidates with ≥24-hour antibiotic utilization on admission, recent prebiotic or probiotic utilization, artificial nutrition, acute gastrointestinal disorders, severe traumatic brain injury, recent hospitalization, institutionalization, expected discharge ≤48 hours, or admission for end-of-life care. A trained research team followed a standardized interview protocol to collect sociodemographic, clinical, and laboratory data on admission and throughout the hospital stay. Our exposure measures were gut microbiota alpha and beta diversities, taxa relative abundance, and core microbiome. Our primary outcome was delirium, assessed twice daily using the Confusion Assessment Method. Delirium was detected in 38 participants (29%). We analyzed 257 swab samples. After adjusting for potential confounders, we observed that a greater alpha diversity (higher abundance and richness of microorganisms) was associated with a lower risk of delirium, as measured by the Shannon (odds ratio [OR] = 0.77; 95% confidence interval [CI] = 0.60-0.99; p = .042) and Pielou indexes (OR = 0.69; 95% CI = 0.51-0.87; p = .005). Bacterial taxa associated with pro-inflammatory pathways (Enterobacteriaceae) and modulation of relevant neurotransmitters (Serratia: dopamine; Bacteroides, Parabacteroides: GABA) were more common in participants with delirium. Gut microbiota diversity and composition were significantly different in acutely ill hospitalized older adults who experienced delirium. Our work is an original proof-of-concept investigation that lays a foundation for future biomarker studies and potential therapeutic targets for delirium prevention and treatment.

Meta-analysis of serological biomarkers at hospital admission for the likelihood of developing delirium during hospitalization

Importance

Identifying biomarkers that, at hospital admission, predict subsequent delirium will help to focus our clinical efforts on prevention and management.

Objective

The study aimed to investigate biomarkers at hospital admission that may be associated with delirium during hospitalization.

Data sources

A librarian at the Fraser Health Authority Health Sciences Library performed searches from 28 June 2021 to 9 July 2021, using the following sources: Medline, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Cochrane Methodology Register, and the Database of Abstracts of Reviews and Effects.

Study selection

The inclusion criteria were articles in English that investigated the link between serum concentration of biomarkers at hospital admission and delirium during hospitalization. Exclusion criteria were single case reports, case series, comments, editorials, letters to the editor, articles that were not relevant to the review objective, and articles concerning pediatrics. After excluding duplicates, 55 studies were included.

Data extraction and synthesis

This meta-analysis followed the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) protocol. Independent extraction, with the consensus of multiple reviewers, was used to determine the final studies included. The weight and heterogeneity of the manuscripts were calculated using inverse covariance with a random-effects model.

Main outcomes and measures

Differences in mean serum concentration of biomarkers at hospital admission between patients who did and did not develop delirium during hospitalization.

Results

Our search found evidence that patients who developed delirium during hospitalization had, at hospital admission, significantly greater concentrations of certain inflammatory biomarkers and one blood-brain barrier leakage marker than patients who did not develop delirium during hospitalization (differences in the mean: cortisol: 3.36 ng/ml, p < 0.0001; CRP: 41.39 mg/L, p < 0.00001; IL-6: 24.05 pg/ml, p < 0.00001; S100β 0.07 ng/ml, p < 0.00001). These differences were independent of other confounding variables such as the patient's severity of illness. A significantly lower serum concentration, at hospital admission, of acetylcholinesterase (difference in the means -0.86 U/ml, p = 0.004) was also associated with an increased vulnerability to developing delirium during hospitalization.

Conclusion and relevance

Our meta-analysis supports the hypothesis that patients with hypothalamic-pituitary axis dysfunction, increased blood-brain barrier permeability, and chronic overload of the cholinergic system, at hospital admission, are more vulnerable to developing delirium during hospitalization.

Age-dependent differences and similarities in the plasma proteomic signature of postoperative delirium

Delirium is an acute confusional state and a common postoperative morbidity. Prevalent in older adults, delirium occurs at other ages but it is unclear whether the pathophysiology and biomarkers for the condition are independent of age. We quantified expression of 273 plasma proteins involved in inflammation and cardiovascular or neurologic conditions in 34 middle-aged and 42 older patients before and one day after elective spine surgery. Delirium was identified by the 3D-CAM and comprehensive chart review. Protein expression was measure by Proximity Extension Assay and results were analyzed by logistic regression, gene set enrichment, and protein-protein interactions. Twenty-two patients developed delirium postoperatively (14 older; 8 middle-aged) and 89 proteins in pre- or 1-day postoperative plasma were associated with delirium. A few proteins (IL-8, LTBR, TNF-R2 postoperatively; IL-8, IL-6, LIF, ASGR1 by pre- to postoperative change) and 12 networks were common to delirium in both age groups. However, there were marked differences in the delirium proteome by age; older patients had many more delirium-associated proteins and pathways than middle-aged subjects even though both had the same clinical syndrome. Therefore, there are age-dependent similarities and differences in the plasma proteomic signature of postoperative delirium, which may signify age differences in pathogenesis of the syndrome.

Preclinical and translational models for delirium: Recommendations for future research from the NIDUS delirium network

Delirium is a common, morbid, and costly syndrome that is closely linked to Alzheimer's disease (AD) and AD-related dementias (ADRD) as a risk factor and outcome. Human studies of delirium have advanced our knowledge of delirium incidence and prevalence, risk factors, biomarkers, outcomes, prevention, and management. However, understanding of delirium neurobiology remains limited. Preclinical and translational models for delirium, while challenging to develop, could advance our knowledge of delirium neurobiology and inform the development of new prevention and treatment approaches. We discuss the use of preclinical and translational animal models in delirium, focusing on (1) a review of current animal models, (2) challenges and strategies for replicating elements of human delirium in animals, and (3) the utility of biofluid, neurophysiology, and neuroimaging translational markers in animals. We conclude with recommendations for the development and validation of preclinical and translational models for delirium, with the goal of advancing awareness in this important field.

A Review of Biomarkers in Delirium Superimposed on Dementia (DSD) and Their Clinical Application to Personalized Treatment and Management

Delirium superimposed on dementia (DSD) occurs when patients with pre-existing dementia develop delirium. This complication causes patients to become impaired, posing safety concerns for both hospital staff and patients. Furthermore, there is an increased risk of worsening functional disability and death. Despite medical advances, DSD provides both diagnostic and therapeutic challenges to providers. Identifying at-risk patients and providing personalized medicine and patient care can decrease disease burden in a time-efficient manner. This review delves into bioinformatics-based studies of DSD in order to design and implement a personalized medicine-based approach. Our findings suggest alternative medical treatment methods based on gene-gene interactions, gene-microRNA (miRNA) interactions, gene-drug interactions, and pharmacogenetic variants involved in dementia and psychiatric disorders. We identify 17 genes commonly associated with both dementia and delirium including apolipoprotein E (ApoE), brain-derived neurotrophic factor (BDNF), catechol-O-methyltransferase (COMT), butyrylcholinesterase (BChE), acetylcholinesterase (AChE), DNA methyltransferase 1 (DNMT1), prion protein (PrP), tumor necrosis factor (TNF), serine palmitoyltransferase long chain base subunit 1 (SPTLC1), microtubule-associated protein tau (MAPT), alpha-synuclein (αS), superoxide dismutase 1 (SOD1), amyloid beta precursor protein (APP), neurofilament light (NFL), neurofilament heavy, 5-hydroxytryptamine receptor 2A (HTR2A), and serpin family A member 3 (ERAP3). In addition, we identify six main genes that form an inner concentric model, as well as their associated miRNA. The FDA-approved medications that were found to be effective against the six main genes were identified. Furthermore, the PharmGKB database was used to identify variants of these six genes in order to suggest future treatment options. We also looked at previous research and evidence on biomarkers that could be used to detect DSD. According to research, there are three types of biomarkers that can be used depending on the stage of delirium. The pathological mechanisms underlying delirium are also discussed. This review will identify treatment and diagnostic options for personalized DSD management.

Brain injury biomarkers do not predict delirium in acutely ill older patients: a prospective cohort study

Delirium is a common, serious, and often preventable neuropsychiatric emergency mostly characterized by a disturbance in attention and awareness. Systemic insult and inflammation causing blood-brain-barrier (BBB) damage and glial and neuronal activation leading to more inflammation and cell death is the most accepted theory behind delirium's pathophysiology. This study aims to evaluate the relationship between brain injury biomarkers on admission and delirium in acutely ill older patients. We performed a prospective cohort study which analyzed plasma S100B levels at admission in elderly patients. Our primary outcome was delirium diagnosis. Secondary outcomes were association between S100B, NSE and Tau protein and delirium diagnosis and patients' outcomes (admissions to intensive care, length of hospital stay, and in-hospital mortality). We analyzed 194 patients, and 46 (24%) developed delirium, 25 on admission and 21 during hospital stay. Median of S100B at admission in patients who developed delirium was 0.16 and median was 0.16 in patients who didn't develop delirium (p: 0.69). Levels S100B on admission did not predict delirium in acutely ill elderly patients.Trial registration: The study was approved by the local institutional review board (CAPPESq, no. 77169716.2.0000.0068, October 11, 2017) and registered in Brazilian Clinical Trials Registry (ReBEC, no. RBR-233bct).

Neutrophil to lymphocyte ratio and platelet to lymphocyte ratio as prognostic predictors for delirium in critically ill patients: a systematic review and meta-analysis

INTRODUCTION

In this systematic review and meta-analysis, we aim to analyze the current literature to evaluate neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) values among critically ill patients who develop delirium as compared to those who do not.

METHODS

PubMed, Web of Science, and Scopus were used to conduct a systematic search for relevant publications published before June 12, 2022. The Newcastle-Ottawa scale was used for quality assessment. Because a significant level of heterogeneity was found, we used the random-effects model to generate pooled effects.

RESULTS

Twenty-four studies including 11,579 critically ill patients, of whom 2439 were diagnosed with delirium, were included in our meta-analysis. Compared with the non-delirious group, the delirious group's NLR levels were significantly higher (WMD = 2.14; CI 95% = 1.48-2.80, p < 0.01). In the subgroup analysis according to the type of critical condition, the NLR levels in patients of delirious group were significantly more than those of non-delirious group in studies on POD, PSD and PCD (WMD = 1.14, CI 95% = 0.38-1.91, p < 0.01, WMD = 1.38, CI 95% = 1.04-1.72, p < 0.001, and WMD = 4.22, CI 95% = 3.47-4.98, p < 0.001, respectively). However, compared with the non-delirious group, the delirious group's PLR levels were not significantly different (WMD = 1.74; CI 95% = -12.39-15.86, p = 0.80).

CONCLUSION

Our findings support NLR to be a promising biomarker that can be readily integrated into clinical settings to aid in the prediction and prevention of delirium.

Effect of tourniquet technique on postoperative delirium in elderly patients with total knee arthroplasty: a randomized single-blind controlled trial

BACKGROUND

The tourniquet technique is often used in total knee arthroplasty (TKA). However, its effect on postoperative delirium (POD) in elderly patients undergoing TKA is unknown.  METHODS: This prospective randomized controlled trial assessed the eligibility of 245 elderly patients. A total of 197 patients who met the inclusion criteria were randomly divided into a tourniquet group (n = 98) and a non-tourniquet group (n = 99). The primary outcome was the incidence of POD within 72 h after surgery. The secondary outcome was the quality of rehabilitation, including inflammatory reaction, postoperative pain, hypoproteinemia and anemia.

RESULTS

Of 245 patients, 184 patients completed this clinical trial, with 92 cases in each group. There were 14 patients (15.22%) with POD in the tourniquet group and 5 patients (5.43%) in the non-tourniquet group (95% CI 1.076 to 9.067, P = 0.029). The changes in white blood cell count (WBC), the proportion of neutrophils (NEUT%), c-reactive protein (CRP), interleukin-6 (IL-6) and middle patellar circumference in the tourniquet group were higher than those in the non-tourniquet group (P < 0.05). The visual analog scale (VAS) at rest and activity in the tourniquet group were higher than those in the non-tourniquet group (F = 170.102, P < 0.001 F = 75.391, P < 0.001). There were 41 (44.57%) patients with hypoproteinemia in the tourniquet group and 26 (28.26%) in the non-tourniquet group (95% CI 1.106 to 3.765, P = 0.022).

CONCLUSION

The application of the tourniquet technique in elderly patients with TKA procedures increased the incidence of POD. This may be attributed to the increased inflammatory reaction, severe postoperative pain and hypoproteinemia caused by the tourniquet technique.

TRIAL REGISTRATION

Clinical trial registration number: ChiCTR2100045711. Full date of the first registration: 23/04/2021.

COVID-19 and neurological complications: A review

Infections with viruses have detrimental effects on neurological functions, and even cause severe neurological damage. There is mounting evidence that coronaviruses (CoV) as well as SARS-CoV-2 exhibit neurotropic abilities and might cause neurological problems. Neuroinvasive viruses are not fully understood, which makes it important to investigate their impact on the nervous system. In this paper, we review research into neurological complications associated with CoV.

Elevation of serum plasminogen activator inhibitor-1 predicts postoperative delirium independent of neural damage: a sequential analysis

Older adult surgical patients are susceptible to developing delirium. Early intervention can be initiated if a potential biomarker associated with delirium can be identified during the acute phase of surgery. Therefore, we investigated the changes in the levels of serum inflammatory mediators responsible for delirium. Serum biomarkers were measured preoperatively to postoperative day 3 in 96 patients who underwent esophageal cancer surgery and compared between patients who did and did not develop delirium. Serum concentrations of the brain-derived phosphorylated neurofilament heavy subunit remained at higher levels throughout the entire perioperative period in patients with delirium (n = 15) than in those without delirium (n = 81). The interaction between delirium and non-delirium was significant for plasminogen activator inhibitor-1 (including age as a covariate, F = 13.360, p < 0.0001, η² _p = 0.134, observed power 1.000) during the perioperative periods. Plasminogen activator inhibitor-1 level discriminated between patients with and without clinically diagnosed delirium with significantly high accuracy (area under curve, 0.864; sensitivity, 1.00: negative predictive value, 1.000; p = 0.002). Rapid increases in the levels of serum plasminogen activator inhibitor-1 may enable clinicians to identify patients at risk of developing postoperative delirium and initiate early prevention and intervention.

The inter-relationship between delirium and dementia: the importance of delirium prevention

Delirium and dementia are two frequent causes of cognitive impairment among older adults and have a distinct, complex and interconnected relationship. Delirium is an acute confusional state characterized by inattention, cognitive dysfunction and an altered level of consciousness, whereas dementia is an insidious, chronic and progressive loss of a previously acquired cognitive ability. People with dementia have a higher risk of developing delirium than the general population, and the occurrence of delirium is an independent risk factor for subsequent development of dementia. Furthermore, delirium in individuals with dementia can accelerate the trajectory of the underlying cognitive decline. Delirium prevention strategies can reduce the incidence of delirium and associated adverse outcomes, including falls and functional decline. Therefore, delirium might represent a modifiable risk factor for dementia, and interventions that prevent or minimize delirium might also reduce or prevent long-term cognitive impairment. Additionally, understanding the pathophysiology of delirium and the connection between delirium and dementia might ultimately lead to additional treatments for both conditions. In this Review, we explore mechanisms that might be common to both delirium and dementia by reviewing evidence on shared biomarkers, and we discuss the importance of delirium recognition and prevention in people with dementia.

In this Review, Fong and Inouye explore mechanisms that might be common to both delirium and dementia. They present delirium as a possible modifiable risk factor for dementia and discuss the importance of delirium prevention strategies in reducing this risk.

Delirium and dementia are frequent causes of cognitive impairment among older adults and have a distinct, complex and interconnected relationship.

Delirium prevention strategies have been shown to reduce not only the incidence of delirium but also the incidence of adverse outcomes associated with delirium such as falls and functional decline.

Adverse outcomes associated with delirium, such as the onset of dementia symptoms in individuals with preclinical dementia, and/or the acceleration of cognitive decline in individuals with dementia might also be delayed by the implementation of delirium prevention strategies.

Evidence regarding the association of systemic inflammatory and neuroinflammatory biomarkers with delirium is variable, possibly as a result of co-occurring dementia pathology or disruption of the blood–brain barrier.

Alzheimer disease pathology, even prior to the onset of symptoms, might have an effect on delirium risk, with potential mechanisms including neuroinflammation and gene–protein interactions with the APOE ε4 allele.

Novel strategies, including proteomics, multi-omics, neuroimaging, transcranial magnetic stimulation and EEG, are beginning to reveal how changes in cerebral blood flow, spectral power and connectivity can be associated with delirium; further work is needed to expand these findings to patients with delirium superimposed upon dementia.

Challenges in the Detection of Clinically Useful Biomarkers for the Diagnosis of Delirium in Older People in the Emergency Department-A Case-Control Study

Background: The identification of biomarkers associated with delirium in the emergency department could contribute to the understanding, prediction and diagnosis of this disorder. The present study was carried out to identify biomarkers included in easily and quickly obtained standard blood examinations in older patients with delirium in the emergency department. Methods: A case–control study was carried out in the emergency department of Francesc de Borja Hospital (Gandía, Valencia, Spain). Older adults (≥65 years of age) diagnosed with delirium (n = 128) were included. Cases due to alcohol or substance abuse were excluded. Controls were selected on a randomized basis from the remaining patients (n = 128). All laboratory test parameters included in the routine blood and urine tests of the emergency department were collected. Results: The mean age of the patients was 81.24 ± 7.51 years, and 56.2% were males, while the mean age of the controls was 78.97 ± 7.99 years, and 45.3% were males. Significant differences were found between the cases and controls in relation to the following parameters: urea 43 (32–58) mg/dL versus 50 (37–66) mg/dL, respectively; neutrophils 69.6 (62.05–78.75)% versus 75.5 (65.1–83.2)%; monocytes 8.7 (7–10.4)% versus 7.6 (5.5–9.2)%; platelets 213 (159–266) × 10⁹/L versus 224 (182–289) × 10⁹/L; neutrophil–lymphocyte ratio 3.88 (2.45–7.07) versus 5 (2.75–8.83); platelet–lymphocyte ratio 281.4 (210–360) versus 357.1 (257.8–457.1); and mean platelet volume 10.6 (10–11.5) fl versus 10.4 (9.67–10.9) fl. Although the mean values were above desirable levels in both groups, they were higher for most parameters in the control group. No significant differences were observed in C-reactive protein concentration (9.99 (1.69–51) mg/L versus 12.3 (3.09–65.97) mg/L). Conclusions: The identification of delirium biomarkers poses difficulties due to the urgent nature of the disorders found in older people admitted to the emergency department. Research in this field is needed, since it would allow early identification and treatment of delirium.

Effects and Causes of Detraining in Athletes Due to COVID-19: A Review

Several aspects of systemic alterations caused by the SARS-CoV-2 virus and the resultant COVID-19 disease have been currently explored in the general population. However, very little is known about these particular aspects in sportsmen and sportswomen. We believe that the most important element to take into account is the neuromuscular aspect, due to the implications that this system entails in motion execution and coordination. In this context, deficient neuromuscular control when performing dynamic actions can be an important risk factor for injury. Therefore, data in this review refer mainly to problems derived in the short term from athletes who have suffered this pathology, taking into account that COVID-19 is a very new disease and the presented data are still not conclusive. The review addresses two key aspects: performance alteration and the return to regular professional physical activity. COVID-19 causes metabolic-respiratory, muscular, cardiac, and neurological alterations that are accompanied by a situation of stress. All of these have a clear influence on performance but at the same time in the strategy of returning to optimal conditions to train and compete again after infection. From the clinical evidence, the resumption of physical training and sports activity should be carried out progressively, both in terms of time and intensity.

Interleukin 8 in postoperative delirium – Preliminary findings from two studies

Objective

Studies have suggested that inflammation contributes to the pathogenesis of postoperative delirium, but previous results on the proinflammatory cytokine IL-8 in plasma are contradictory. Additionally, a significant fraction of IL-8 is bound to erythrocytes, but the relevance of whole blood IL-8 in delirium has not been studied. In this work, we analyzed the association of postoperative delirium with levels of unbound IL-8 in plasma and levels of IL-8 in whole blood in patients from two studies which were conducted in our department and have not been presented previously. We assessed the prognostic value of whole blood IL-8.

Methods

Plasma/whole blood IL-8 was measured at least once in N ​= ​504 patients preoperatively, on day one (d1) and/or three months after surgery in the BioCog observational study. Whole blood IL-8 was measured in N ​= ​64 patients from the PHYDELIO trial preoperatively, on d1 and d7 after surgery. For the determination of whole blood IL-8, EDTA-preserved blood samples underwent lysis by adding Triton-X100 surfactant. Plasma and whole blood IL-8 levels were assessed with two different immunoassay kits. Delirium was appraised systematically for seven postoperative days according to DSM criteria using two comparable protocols consisting of validated screening tools.

Results

Delirium occurred in 25% of BioCog and 14% of PHYDELIO patients. In BioCog, IL-8 was elevated on d1 and in delirious patients. A steeper postoperative increase in delirium was confounded by surgery-related factors. A crescendo-decrescendo pattern of whole blood IL-8 levels was observed in non-delirious patients with a peak on d1. This pattern was more distinct in delirious BioCog patients, but inverted in delirious PHYDELIO patients. Preoperative whole blood IL-8>318.4 ​pg/mL (reference <150 ​pg/mL) had adequate sensitivity (0.79/0.78) and specificity (0.53/0.67) for delirium in both samples.

Conclusion

Our results contribute to an inflammatory hypothesis of postoperative delirium.

Preliminary Study of Serum Biomarkers Associated With Delirium After Major Cardiac Surgery

OBJECTIVES

The objective of this study was to identify novel serum biomarkers specific to postoperative delirium after major cardiac surgery to provide insight into the pathologic processes involved in delirium and its sequelae.

DESIGN

Nested, case-control study.

SETTING

Cardiac surgical intensive care unit in a single-site hospital setting.

PARTICIPANTS

The study comprised 24 older adults (aged >60 years) undergoing major cardiac surgery with cardiopulmonary bypass.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was a positive screen for delirium from postoperative days one through three based on criteria included in the long form of the Confusion Assessment Method. A multiplexed proteomic approach was applied using proximity extension assays to identify and quantify proteins found in serum collected on the day of surgery and postoperative day one in delirious and nondelirious patient cohorts. An increase in serum fibroblast growth factor (FGF)-21 levels was identified in the delirious cohort from a presurgery baseline of (mean ± standard deviation) 5.0 ± 1.1 log2 abundance (95% confidence interval [CI], 4.3-5.7) to 6.7 ± 1.6 log2 abundance (95% CI, 5.7-7.7; p = 0.01) postsurgery. A similar increase was identified in FGF-23 from a presurgery baseline of 1.7 ± 1.3 log2 abundance (95% CI, 0.8-2.5) to 3.4 ± 2.2 log2 abundance (95% CI, 2.0-4.8; p = 0.06) postsurgery. An increase in interleukin-6 serum levels also was identified in the delirious cohort from a presurgery baseline of 3.8 ± 1.1 log2 abundance (95% CI, 3.1-4.5) to 8.7 ± 1.9 log2 abundance (95% CI, 7.5-9.9; p < 0.0001) postsurgery. However, the increase in interleukin-6 serum levels of the nondelirious cohort also met the study's threshold for statistical significance (p < 0.0001). Finally, an increase in monocyte chemotactic protein-3 serum levels was identified in the delirious cohort from a presurgery baseline of 4.1 ± 0.9 log2 abundance (95% CI, 3.6-4.7) to 6.1 ± 2.0 log2 abundance (95% CI, 4.8-7; p = 0.009) postsurgery.

CONCLUSIONS

FGF-21, FGF-23, interleukin-6, and monocyte chemotactic protein-3 serum levels were increased postoperatively in patients who developed delirium after major cardiac surgery. This study identified two members of the FGF family as potential putative systemic biomarkers for postoperative delirium after cardiac surgery, suggesting a possible role for metabolic recovery in the pathophysiologic mechanisms underlying neurocognitive dysfunction.

Biomarker Analysis for Combination Therapy of Vitamin C and Thiamine in Septic Shock: A Post-Hoc Study of the ATESS Trial

INTRODUCTION

We evaluated the effects of vitamin C and thiamine administration on biomarkers in patients with septic shock.

METHODS

This was a post-hoc analysis of the Ascorbic Acid and Thiamine Effect in Septic Shock (ATESS) trial, a multicenter, double-blind, randomized controlled trial. Patients were randomized to either a treatment group (intravenous vitamin C and thiamine for 48 h) or a control group. Interleukin (IL)-6, IL-10, angiopoietin-II (AP2), and S100β were assessed at baseline and at 72 h. The primary outcomes were the biomarker levels at 72 h, and the secondary outcome was reduction rate.

RESULTS

Forty-five patients were assigned to the treatment group and 52 were assigned to the control group. Baseline biomarker levels and at 72 h were not significantly different between the treatment and the placebo groups. The reduction rates were not significantly different between the two groups. These outcome variables showed fair diagnostic accuracy for predicting 28-day mortality according to the area under the receiver operating characteristic curve.

CONCLUSION

Vitamin C and thiamine administration during the early phase of septic shock did not significantly change prognostic biomarker levels of IL-6, IL-10, AP2, and S100β.

TRIAL REGISTRATION

NCT, ClinicalTrials.gov NCT03756220, ATESS. Registered 28 November 2018, https://clinicaltrials.gov/ct2/show/NCT03756220.

Development and validation of prediction models for neurocognitive disorders in adult patients admitted to the ICU with sleep disturbance

BACKGROUND

Neurocognitive disorders (NCDs) and sleep disturbance are highly prevalent in the perioperative period and intensive care unit (ICU). There has been a lack of individualized evaluation tools designed for the high-risk NCDs in critically ill patients with sleep disturbance.

OBJECTIVES

The aim of this study was to develop and validate prediction models for NCDs among adult patients with sleep disturbance.

METHODS

The R software was used to analyze the dataset of adult patients admitted to the ICU with sleep disturbance, who were diagnosed following the codes of the International Classification of Diseases, 9th Revision (ICD-9) and 10th Revision (ICD-10) using the MIMIC-IV database. We used logistic regression and LASSO analyses to identify important risk factors associated with NCDs and develop nomograms for NCDs predictions. We measured the performances of the nomograms using the bootstrap resampling procedure, sensitivity, specificity of the receiver operating characteristic (ROC), area under the ROC curves (AUC), and decision curve analysis (DCA).

RESULTS

The prediction models shared the 10 risk factors (age, gender, midazolam, morphine, glucose, diabetes diseases, potassium, international normalized ratio, partial thromboplastin time, and respiratory rate). Cardiovascular diseases were included in the logistic regression, the sensitivity was 74.1%, and specificity was 64.6%. When platelet and Glasgow Coma Score (GCS) were included and cardiovascular diseases were removed in the LASSO prediction model, the sensitivity was 86.1% and specificity was 82.8%. Discriminative abilities of the logistic prediction and LASSO prediction models for NCDs in the validation set were evaluated as the AUC scores, which were 0.730 (95% CI 0.716-0.743) and 0.920 (95% CI 0.912-0.927). Net benefits of the prediction models were observed at threshold probabilities of 0.567 and 0.914.

CONCLUSIONS

The LASSO prediction model showed better performance than the logistic prediction model and should be preferred for nomogram-assisted decisions on clinical risk management of NCDs among adult patients with sleep disturbance in the ICU.

Consistent patterns in the inconsistent associations of Insulin-like growth factor 1 (IGF-1), C-Reactive Protein (C-RP) and Interleukin 6 (IL-6) levels with delirium in surgical populations. A systematic review and meta-analysis

BACKGROUND

Biomarkers for delirium could increase diagnostic accuracy and may help to identify pathological pathways. Until now study findings concerning cytokine levels have been inconsistent.

AIMS

Systematic review and meta-analysis investigating the association between peripheral levels of Insulin-like Growth Factor-1 (IGF-1), C-Reactive Protein (C-RP) and Interleukin-6 (IL-6) and delirium in surgical patients, and to explore if there are distinct/specific patterns that may potentially explain inconsistent results.

METHODS

PubMed, Scopus, CINAHL, Cochrane, and EMBASE databases were searched. Inclusion criteria were: prospective studies, surgical populations excluding preoperative delirium, available data. The following were collected: type of operation (orthopaedic, abdominal, etc), the timing of operation (acute, elective, both), demographics, number of participants with delirium, time of preoperative blood withdrawal, and preoperative levels of each biomarker.

RESULTS

Low levels of IGF-1 (n = 7 studies) are significantly associated with post-operative delirium in abdominal surgical samples. High levels of C-RP (n = 9) are associated with delirium in acute orthopaedic and elective abdominal operations. IL-6 (n = 14) is a significant predictor of post-operative delirium in a variety of surgical conditions (elective or acute).

DISCUSSION

A common pattern exists in the otherwise conflicting reported findings. This similarity may reflect different underling mechanisms and predisposing factors like cachexia and catabolic stages. It seems that delirium in abdominal surgery is triggered by IGF-1 disturbances, while in other surgeries by an inflammatory reaction.

CONCLUSIONS

Despite the contradictory results concerning the association of IGF-1, C-RP and IL-6 with postoperative delirium, the present meta-analysis shows that there are certain patterns. IL-6 seems a consistent predictor for delirium in surgical samples.

Development and validation of a risk score for predicting postoperative delirium after major abdominal surgery by incorporating preoperative risk factors and surgical Apgar score

STUDY OBJECTIVE

To develop and validate a simple delirium-predicting scoring system in patients undergoing major abdominal surgery by incorporating preoperative risk factors and intraoperative surgical Apgar score (SAS).

DESIGN

Observational retrospective cohort study.

SETTING

A tertiary general hospital in China.

PATIENTS

1055 patients who received major abdominal surgery from January 2015 to December 2019.

MEASUREMENTS

We collected data on preoperative and intraoperative variables, and postoperative delirium. A risk scoring system for postoperative delirium in patients after major open abdominal surgery was developed and validated based on traditional logistic regression model. The elastic net algorithm was further developed and evaluated.

MAIN RESULTS

The incidence of postoperative delirium was 17.8% (188/1055) in these patients. They were randomly divided into the development (n = 713) and validation (n = 342) cohorts. Both the logistic regression model and the elastic net regression model identified that advanced age, arrythmia, hypoalbuminemia, coagulation dysfunction, mental illness or cognitive impairments and low surgical Apgar score are related with increased risk of postoperative delirium. The elastic net algorithm has an area under the receiver operating characteristic curve (AUROC) of 0.842 and 0.822 in the development and validation cohorts, respectively. A prognostic score was calculated using the following formula: Prognostic score = Age classification (0 to 3 points) + arrythmia + 2 * hypoalbuminemia + 2 * coagulation dysfunction + 4 * mental illness or cognitive impairments + (10-surgical Apgar score). The 22-point risk scoring system had good discrimination and calibration with an AUROC of 0.823 and 0.834, and a non-significant Hosmer-Lemeshow test P = 0.317 and P = 0.853 in the development and validation cohorts, respectively. The bootstrapping internal verification method (R = 1000) yielded a C-index of 0.822 (95% CI: 0.759-0.857).

CONCLUSION

The prognostic scoring system, which used both preoperative risk factors and surgical Apgar score, serves as a good first step toward a clinically useful predictive model for postoperative delirium in patients undergoing major open abdominal surgery.

Delirium Severely Worsens Outcome in Patients with COVID-19-A Retrospective Cohort Study from Temporary Critical Care Hospitals

Delirium is a sign of deterioration of homeostasis and worse prognosis. The aim of this study was to investigate the frequency, risk factors and prognosis of delirium in patients with COVID-19 in a temporary acute setting hospital. A retrospective cohort analysis of data collected between October 2020 and February 2021 from two temporary acute care hospitals was performed. All consecutive hospitalized patients ≥18 years old with COVID-19 were included. An assessment of consciousness was carried out at least two times a day, including neurological examination. Delirium was identified through retrospective chart review according to DSM-5 criteria if present at least once during hospitalization. Analysis included 201 patients, 39 diagnosed with delirium (19.4%). Delirious patients were older (p < 0.001), frailer (p < 0.001) and the majority were male (p = 0.002). Respiratory parameters were worse in this group with higher oxygen flow (p = 0.013), lower PaO2 (p = 0.043) and higher FiO2 (p = 0.006). The mortality rate was significantly higher in patients with delirium (46.15% vs 3.70%, p < 0.001) with OR 17.212 (p < 0.001) corrected for age and gender. Delirious patients experienced significantly more complications: cardiovascular (OR 7.72, p < 0.001), pulmonary (OR 8.79, p < 0.001) or septic (OR 3.99, p = 0.029). The odds of mortality in patients with COVID-19 presenting with delirium at any point of hospitalization were seventeen times higher.

Echo intensity is more useful in predicting hospital-associated complications than conventional sarcopenia-related parameters in acute hospitalized older patients

BACKGROUND

Hospital-associated complications are associated with adverse outcomes after discharge, and a method to help predict the occurrence of these complications needs to be established. Sarcopenia is thought to be one of the factors associated with hospital-associated complication, but sarcopenia assessment in hospitalized patients is often difficult. Focus has recently been placed on morphological and qualitative evaluation of muscle by ultrasound as an index of sarcopenia. Therefore, in this study, we sought to clarify the association of hospital-associated complication with muscle thickness or echo intensity measured by ultrasound and with commonly used sarcopenia-related parameters.

METHODS

This is a prospective observational cohort study with 156 hospitalized older patients recruited over a year. Bilateral thigh muscle thickness of rectus femoris and vastus intermedius, echo intensity and corrected echo intensity of rectus femoris were measured by ultrasound. Also measured were the sarcopenia-related parameters of handgrip strength, skeletal muscle index, and maximum calf circumference. Hospital-associated complication was defined as the occurrence of any of the following complications: delirium, functional decline, incontinence, falls, pressure injuries, and nosocomial infections.

RESULTS

Of 156 patients enrolled at admission, hospital-associated complication was observed in 70 (54.3%). With-hospital-associated complication group had a higher prevalence of emergency admission and a higher corrected echo intensity than without-hospital-associated complication group. Multivariate logistic regression analysis showed that only higher corrected echo intensity was associated with hospital-associated complication (odds ratio 1.036; 95% confidence interval, 1.001-1.072), while handgrip strength, bilateral thigh muscle thickness, skeletal muscle index, and maximum calf circumference were not.

CONCLUSIONS

Corrected echo intensity might be a useful parameter to help predict hospital-associated complication in acute hospitalized older patients and might contribute to establishing a strategy to prevent hospital-associated complication.

Elevated Monocyte Chemoattractant Protein-1 as the Independent Risk Factor of Delirium after Cardiac Surgery. A Prospective Cohort Study

BACKGROUND

The pathogenesis of postoperative delirium is largely unknown. The primary objective of this study is to assess whether increased levels of monocyte chemoattractant protein-1 (MCP-1) and high-sensitivity C-reactive protein (hsCRP) are associated with postoperative delirium in patients who have undergone cardiac surgery. The secondary objective is to investigate whether any association between raised inflammatory biomarkers levels and delirium is related to surgical and anesthetic procedures or mediated by pre-existing psychiatric conditions associated with raised pro-inflammatory markers levels.

METHODS

The patients were screened for cognitive impairment one day preoperatively with the use of the Mini-Mental State Examination Test and the Clock Drawing Test. A diagnosis of major depressive disorder (MDD) and anxiety disorders was established on the basis of Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria. Blood samples were collected pre- and postoperatively for hsCRP and chemokine levels.

RESULTS

Postoperative delirium developed in 34% (61 of 177) of patients. Both pre- and postoperative hsCRP, and preoperative MCP-1 levels were associated with postoperative delirium in univariate comparisons; p = 0.001; p < 0.001; p < 0.001, respectively. However, according to a multivariable logistic regression analysis, only a raised MCP-1 concentration before surgery was independently associated with postoperative delirium, and related to advancing age, preoperative anxiety disorders and prolonged intubation.

CONCLUSIONS

The present study suggests that an elevated preoperative MCP-1 concentration is associated with delirium after cardiac surgery. Monitoring of this inflammatory marker may reveal the cardiovascular disease (CVD) patients who are at risk of neuropsychiatric syndromes development.

Prospective Randomized Controlled Pilot Study of High-Intensity Lightbox Phototherapy to Prevent ICU-Acquired Delirium Incidence

Background

This study aimed to evaluate the role of disturbed circadian rhythm in potentiating intensive care unit (ICU)-acquired delirium.Previous studies have demonstrated bright light therapy (BLT) as an effective modality to improve sleeping patterns and cognitive function in non-critically ill patients. However, its benefit in the ICU has not been clearly established. In this study, we aimed to evaluate the application of daily high-intensity phototherapy at the bedside to deter ICU delirium incidence and duration.

Methodology

This was a single center, prospective study conducted in ICUs at the Carilion Roanoke Memorial Hospital in Roanoke, VA. Adults patients admitted to the ICU from July 9, 2018 to March 20, 2020 were included in the study. The patients were subjected to 30-minute BLT session (10,000 lux) at the bedside starting at 0700 while in the ICU. Patients were randomized into either the control group (standard hospital lighting) or phototherapy group. Data were analyzed using Wilcoxon rank sum test for continuous variables, Pearson chi-square test for categorical variables, and logistic regression for multivariable analysis that examined significant risk factors for ICU delirium.

Results

Delirium incidence between BLT (18%) and control (17.5%) groups was non-significant. Total number of delirium-free, coma-free days, as determined by Confusion Assessment Method for the ICU, demonstrated no differences between groups with a median of 28 days (p = 0.516). In multivariable analysis, patients with a Sequential Organ Failure Assessment Score >3 also showed no significant change in ICU delirium incidence when provided bedside BLT compared to those with standard hospital lighting (odds ratio: 0.08; 95% confidence interval: 0.002-1.40; p = 0.867).

Conclusions

In this randomized control pilot study, daily morning 10,000 lux BLT of 30-minute duration alone was not associated with a significant decrease in ICU-acquired delirium incidence or duration compared to standard hospital lighting. Future studies should consider a nuanced approach to better elucidate the role of disturbed circadian rhythm in influencing ICU-acquired delirium by not only undertaking BLT during the day but also minimizing nighttime light exposure.

Delirium after Deep Brain Stimulation in Parkinson's Disease

Deep brain stimulation is a primary treatment method that improves motor and motor complications in patients with advanced Parkinson's disease. Delirium is a common and serious complication following deep brain stimulation. However, the clinical attention toward this complication remains insufficient. Advanced age, cognitive decline, and the severity of the disease may all be risk factors for delirium. The presence of delirium may also affect cognitive function and disease prognosis. Neurotransmitters such as acetylcholine and dopamine may be involved in the occurrence of delirium. Furthermore, inflammation, the effects of microlesioning of local nuclei, and brain atrophy may also play roles in the onset of delirium. Nonpharmacological therapy appears to be the primary treatment for postoperative delirium in Parkinson's disease. The current article reviews the pathogenesis, epidemiology, prognosis, and treatment of delirium following deep brain stimulation in Parkinson's disease to help clinicians better understand this common complication and to prevent, identify, and treat it as soon as possible, as well as to provide more accurate treatment for patients.

Delirium in older adults

This narrative review provides a broad examination of the most current concepts on the etiopathogenesis, diagnosis, prevention, and treatment of delirium, an acute neuropsychiatric syndrome characterized by fluctuating changes in cognition and consciousness. With the interaction of underlying vulnerability and severity of acute insults, delirium can occur at any age but is particularly frequent in hospitalized older adults. Delirium is also associated with numerous adverse outcomes, including functional impairment, cognitive decline, increased healthcare costs, and death. Its diagnosis is based on clinical and cognitive assessments, preferably following systematized detection instruments, such as the Confusion Assessment Method (CAM). Delirium and its consequences are most effectively fought using multicomponent preventive interventions, like those proposed by the Hospital Elder Life Program (HELP). When prevention fails, delirium management is primarily based on the identification and reversal of precipitating factors and the non-pharmacological control of delirium symptoms. Pharmacological interventions in delirium should be restricted to cases of dangerous agitation or severe psychotic symptoms.

Delusion and Delirium in Neurodegenerative Disorders: An Overlooked Relationship?

Delusions are part of the neuropsychiatric symptoms that patients suffering from neurodegenerative conditions frequently develop at some point of the disease course and are associated with an increased risk of cognitive and functional decline. Delirium is a syndrome characterized by acute onset of deficits in attention, awareness, and cognition that fluctuate in severity over a short time period. Delusions and delirium are frequently observed in the context of neurodegeneration, and their presence can easily mislead clinicians toward a misdiagnosis of psychiatric disorder further delaying the proper treatment. Risk factors for developing delusion and delirium in neurodegenerative conditions have been investigated separately while the possible interplay between these two conditions has not been explored so far. With this study, we aim to achieve a more comprehensive picture of the relationship between delusions and delirium in neurodegeneration by analyzing prevalence and subtypes of delusions in different neurodegenerative disorders; providing an overview of clinical tools to assess delusions in neurodegenerative patients and how delusions are covered by delirium assessment tools and discussing the possible common pathophysiology mechanisms between delusion and delirium in neurodegenerative patients. A more extensive characterization of the relationship between delusions and delirium may help to understand whether delusions may constitute a risk factor for delirium and may ameliorate the management of both conditions in patients with neurodegenerative disorders.

Challenges of Delirium Management in Patients with Traumatic Brain Injury: From Pathophysiology to Clinical Practice

Traumatic brain injury (TBI) can initiate a very complex disease of the central nervous system (CNS), starting with the primary pathology of the inciting trauma and subsequent inflammatory and CNS tissue response. Delirium has long been regarded as an almost inevitable consequence of moderate to severe TBI, but more recently has been recognized as an organ dysfunction syndrome with potentially mitigating interventions. The diagnosis of delirium is independently associated with prolonged hospitalization, increased mortality and worse cognitive outcome across critically ill populations. Investigation of the unique problems and management challenges of TBI patients is needed to reduce the burden of delirium in this population. In this narrative review, possible etiologic mechanisms behind post-traumatic delirium are discussed, including primary injury to structures mediating arousal and attention and secondary injury due to progressive inflammatory destruction of the brain parenchyma. Other potential etiologic contributors include dysregulation of neurotransmission due to intravenous sedatives, seizures, organ failure, sleep cycle disruption or other delirium risk factors. Delirium screening can be accomplished in TBI patients and the presence of delirium portends worse outcomes. There is evidence that multi-component care bundles including an analgesia-prioritized sedation algorithm, regular spontaneous awakening and breathing trials, protocolized delirium assessment, early mobility and family engagement can reduce the burden of ICU delirium. The aim of this review is to summarize the approach to delirium in TBI patients with an emphasis on pathogenesis and management. Emerging CNS-active drug therapies that show promise in preclinical studies are highlighted.

Low molecular weight heparin in COVID-19 patients prevents delirium and shortens hospitalization

Background

COVID-19 patients present with delirium during their hospitalization.

Aims

To assess the incidence of delirium in hospitalized COVID-19 patients and analyze the possible association with demographic, clinical, laboratory, and pharmacological factors.

Methods

COVID-19 patients were assessed for clinical signs of delirium and administered the assessment test for delirium and cognitive impairment (4AT) and the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) scales.

Results

Out of the 56 patients of our cohort, 14 (25.0%) experienced delirium. The use of low molecular weight heparin (LMWH) (enoxaparin 1 mg/kg/daily) was less frequent in patients with delirium (p = 0.004) and was accompanied by lower C reactive protein (CRP) levels (p = 0.006).

Discussion

The use of LMWH was associated with absence of delirium, independently of comorbidities and age.

Conclusions

The use of LMWH may help preventing the occurrence of delirium in COVID-19 patients, with possible reduction of length of stay in the hospital and sequelae.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10072-020-04887-4.

Correlation of Serum BACE1 With Emergence Delirium in Postoperative Patients: A Preliminary Study

Background: The mechanism underlying delirium, a common acute fluctuating mental state, may be related to the activation of a neuroinflammatory response. In this study, we attempted to investigate whether plasma inflammatory response markers, vascular and cerebrovascular injury-related markers, and neurodegeneration-associated markers were associated with emergence delirium (ED).

Methods: Patients aged 50 years or above who underwent elective laparoscopic surgery under general anesthesia were included in this study. Delirium was assessed postoperatively with the Richmond Agitation Sedation Scale (RASS) and the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) scale. Plasma samples were collected from ED patients and non-ED patients to test concentrations of inflammation markers, including interleukin 6 (IL-6), chitinase 3-like 1 (CHI3L1), S100 calcium-binding protein B (S100B), lipoprotein-associated phospholipase-A2 (Lp-PLA2), and macrophage migration inhibitory factor (MIF); vascular and cerebrovascular injury-related markers, including intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule (VCAM-1); and neurodegeneration-associated markers, including alpha-synuclein (α-Syn) and β-secretase 1 (BACE1). Binary logistic regression analysis was performed to analyze the relationship between biomarkers and ED, and receiver operating characteristic (ROC) curves were used to analyze the diagnostic value of biomarkers.

Results: A total of 104 patients were included in this study, with an average age of 63.69 ± 7.21. IL-6 (OR = 2.73, 95% CI: 1.66–6.44, P = 0.022), S100B (OR = 4.74, 95% CI: 1.88–11.95, P = 0.001), and BACE1 (OR = 6.54, 95% CI: 2.57–16.65, P < 0.000) were independent biological indicators for the occurrence of ED.CHI3L1, Lp-PLA2, MIF, ICAM-1, VCAM-1, and α-Syn were unrelated to ED. Plasma BACE1 level had a possible diagnostic value for ED [area under curve (AUC) = 0.75, 95% CI: 0.66–0.85], whereas plasma IL-6 (AUC = 0.62, 95% CI: 0.51–0.73) and S100B (AUC = 0.65, 95% CI: 0.54–0.76) levels had little diagnostic value for distinguishing ED vs. non-ED.

Conclusion: Higher levels of systemic inflammation marker IL-6, cerebral inflammation marker S100B, and neurodegeneration-associated marker BACE1 are related to ED. Plasma BACE1 may be a potential diagnostic biomarker for ED.

Neuroinflammation after surgery: from mechanisms to therapeutic targets

Injury is a key driver of inflammation, a critical yet necessary response involving several mediators that is aimed at restoring tissue homeostasis. Inflammation in the central nervous system can be triggered by a variety of stimuli, some intrinsic to the brain and others arising from peripheral signals. Fine-tuned regulation of this response is crucial in a system that is vulnerable due to, for example, aging and ongoing neurodegeneration. In this context, seemingly harmless interventions like a common surgery to repair a broken limb can overwhelm the immune system and become the driver of further complications such as delirium and other perioperative neurocognitive disorders. Here, we discuss potential mechanisms by which the immune system affects the central nervous system after surgical trauma. Together, these neuroimmune interactions are becoming hallmarks of and potential therapeutic targets for multiple neurologic conditions, including those affecting the perioperative space.

A complication of coronavirus disease 2019: delirium

COVID-19 is predominantly a respiratory disease. However, some cases exhibit other features including Central Nervous System symptoms. In the older adult, COVID-19 may present with atypical symptoms, including delirium and its complications. The objective of this study is to describe the relationship between the new type of coronavirus infection and delirium. Systematic research (Cochrane Library and PubMed) was carried out (only upper time limit: April 2020). Publications found through this indexed search were reviewed and manually screened to identify relevant studies. Search terms used included “COVID-19, Delirium, Dementia, Intensive Care Unit”. We manually added articles identified through other sources (i.e., key journals). Older people are at the greatest risk from COVID-19. If infected, they may present delirium. Moreover, it is not exclusive to older people. Delirium is not inevitable; rather, it is preventable. Delirium prevention programs are even more crucial in the era of COVID-19 and cannot be allowed to wither despite the challenges of integrating delirium prevention with COVID-19 care. An acute change in condition, behaviour, or mental status should prompt a delirium screen. As regards the treatment, it is advisable to use non-pharmacological interventions first where possible. Medication may be needed for patients with agitation where there is intractable distress or high risk to self/others.

Serum DBI and biomarkers of neuroinflammation in Alzheimer's disease and delirium

Background

Alzheimer’s disease (AD) patients often express significant behavioral symptoms: for this reason, accessible related biomarkers could be very useful. Neuroinflammation is a key pathogenic process in both AD and delirium (DEL), a clinical condition with behavioral symptoms resembling those of AD.

Methods

A total of n = 30 AD patients were recruited together with n = 30 DEL patients and n = 15 healthy controls (CTRL). Serum diazepam binding inhibitor (DBI), IL-17, IL-6, and TNF-α were assessed by ELISA.

Results

DBI serum levels were increased in AD patients with respect to CTRL (+ 81%), while DEL values were 70% higher than AD. IL-17 was increased in DEL with respect to CTRL (+ 146%), while AD showed dispersed values and failed to reach significant differences. On the other hand, IL-6 showed a more robust increase in DEL with respect to the other two groups (+ 185% and + 205% vs. CTRL and AD, respectively), and TNF-α failed to show any change.

Conclusions

DBI may be a very promising candidate for AD, perhaps marking psychomotor DEL-like symptoms, in view of developing future helping tool for practicing physicians. Furthermore, DBI rise in DEL offers novel cues for a better comprehension of the pathogenesis of this potentially fatal condition.

COVID-19 and Central Nervous System: Entry Routes And

Awareness of the current outbreak of Coronavirus Disease - 2019 (COVID-19) affecting the nervous system and identifying its possible ways to enter the Central Nervous System (CNS) are critical for the prevention and treatment of the disease. Hence, the CNS implications of the COVID-19 since the spread of the virus were reviewed in this study.