Relationship between no-visitation policy and the development of delirium in patients admitted to the intensive care unit

Background

Due to the severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) pandemic, many hospitals imposed a no-visitation policy for visiting patients in hospitals to prevent the transmission of SARS-CoV-2 among visitors and patients. The objective of this study was to investigate the association between the no-visitation policy and delirium in intensive care unit (ICU) patients.

Methods

This was a single-center, before-after comparative study. Patients were admitted to a mixed medical-surgical ICU from September 6, 2019 to October 18, 2020. Because no-visitation policy was implemented on February 26, 2020, we compared patients admitted after this date (after phase) with the patients admitted before the no-visitation policy (before phase) was implemented. The primary outcome was the incidence of delirium during the ICU stay. Cox regression was used for the primary analysis and was calculated using hazard ratios (HRs) and 95% confidence intervals (CIs). Covariates were age, sex, APACHE II, dementia, emergency surgery, benzodiazepine, and mechanical ventilation use.

Results

Of the total 200 patients consecutively recruited, 100 were exposed to a no-visitation policy. The number of patients who developed delirium during ICU stay during the before phase and the after phase were 59 (59%) and 64 (64%), respectively (P = 0.127). The adjusted HR of no-visitation policy for the number of days until the first development of delirium during the ICU stay was 0.895 (0.613–1.306).

Conclusion

The no-visitation policy was not associated with the development of delirium in ICU patients.

Risk factors associated with the development of delirium in general ICU patients. A prospective observational study

Objective

We aimed to analyze risk factors related to the development of delirium, aiming for early intervention in patients with greater risk.

Material and methods

Observational study, including prospectively collected patients treated in a single general ICU. These were classified into two groups, according to whether they developed delirium or not (screening performed using CAM-ICU tool). Demographics and clinical data were analyzed. Multivariate logistic regression analyses were performed to quantify existing associations.

Results

1462 patients were included. 93 developed delirium (incidence: 6.3%). These were older, scored higher on the Clinical Frailty Scale, on the risk scores on admission (SAPS-3 and SOFA), and had a greater number of organ failures (OF). We observed more incidence of delirium in patients who (a) presented more than two OF (20.4%; OR 4.9; CI95%: 2.9–8.2), and (b) were more than 74 years old albeit having <2 OF (8.6%; OR 2.1; CI95%: 1.3–3.5). Patients who developed delirium had longer ICU and hospital length-of-stays and a higher rate of readmission.

Conclusions

The highest risk observed for developing delirium clustered in patients who presented more than 2 OF and patients over 74 years old. The detection of patients at high risk for developing delirium could imply a change in management and improved quality of care.

Serotonin-Its Synthesis and Roles in the Healthy and the Critically Ill

Serotonin (5-hydroxytryptamine, 5-HT) plays two important roles in humans-one central and the other peripheral-depending on the location of the 5-HT pools of on either side of the blood-brain barrier. In the central nervous system it acts as a neurotransmitter, controlling such brain functions as autonomic neural activity, stress response, body temperature, sleep, mood and appetite. This role is very important in intensive care, as in critically ill patients multiple serotoninergic agents like opioids, antiemetics and antidepressants are frequently used. High serotonin levels lead to altered mental status, deliria, rigidity and myoclonus, together recognized as serotonin syndrome. In its role as a peripheral hormone, serotonin is unique in controlling the functions of several organs. In the gastrointestinal tract it is important for regulating motor and secretory functions. Apart from intestinal motility, energy metabolism is regulated by both central and peripheral serotonin signaling. It also has fundamental effects on hemostasis, vascular tone, heart rate, respiratory drive, cell growth and immunity. Serotonin regulates almost all immune cells in response to inflammation, following the activation of platelets.

Preoperative brain MRI features and occurrence of postoperative delirium

OBJECTIVE

Delirium is a frequent complication after surgery with important negative outcomes for affected patients and society. However, it is still largely unknown why some patients have a predisposition for delirium and others not. To increase our understanding of the neural substrate of postoperative delirium, we studied the association between preoperative brain MRI features and the occurrence of delirium after major surgery.

METHODS

A group of 413 patients without dementia (Mean 72 years, SD: 5) was included in a prospective observational two-center study design. The study was conducted at Charité Universitätsmedizin (Berlin, Germany) and the University Medical Center Utrecht (Utrecht, The Netherlands). We measured preoperative brain volumes (total brain, gray matter, white matter), white matter hyperintensity volume and shape, brain infarcts and cerebral perfusion, and used logistic regression analysis adjusted for age, sex, intracranial volume, study center and type of surgery.

RESULTS

Postoperative delirium was present in a total of 70 patients (17%). Preoperative cortical brain infarcts increased the risk of postoperative delirium, although this did not reach statistical significance (OR (95%CI): 1.63 (0.84-3.18). Furthermore, we found a trend for an association of a more complex shape of white matter hyperintensities with occurrence of postoperative delirium (OR (95%CI): 0.97 (0.95-1.00)). Preoperative brain volumes, white matter hyperintensity volume, and cerebral perfusion were not associated with occurrence of postoperative delirium.

CONCLUSION

Our study suggests that patients with preoperative cortical brain infarcts and those with a more complex white matter hyperintensity shape may have a predisposition for developing delirium after major surgery.

Systems Level Analysis and Identification of Pathways and Key Genes Associated with Delirium

Delirium is a complex pathophysiological process, and multiple contributing mechanisms have been identified. However, it is largely unclear how the genes associated with delirium contribute and which of them play key roles. In this study, the genes associated with delirium were retrieved from the Comparative Toxicogenomics Database (CTD) and integrated through a protein-protein interaction (PPI) network. Delirium-associated genes formed a highly interconnected PPI subnetwork, indicating a high tendency to interact and agglomerate. Using the Molecular Complex Detection (MCODE) algorithm, we identified the top two delirium-relevant network modules, M1 and M5, that have the most significant enrichments for the delirium-related gene sets. Functional enrichment analysis showed that genes related to neurotransmitter receptor activity were enriched in both modules. Moreover, analyses with genes located in human accelerated regions (HARs) provided evidence that HAR-Brain genes were overrepresented in the delirium-relevant network modules. We found that four of the HAR-Brain genes, namely APP, PLCB1, NPY, and HTR2A, in the M1 module were highly connected and appeared to exhibit hub properties, which might play vital roles in delirium development. Further understanding of the function of the identified modules and member genes could help to identify therapeutic intervention targets and diagnostic biomarkers for delirium.

Different depths of sedation versus risk of delirium in adult mechanically ventilated patients: A systematic review and meta-analysis

Background

Delirium is multifactorial. This study aimed at determining the association between different depths of sedation and the risk of delirium in adult mechanically ventilated patients.

Methods

A systematic literature retrieval was conducted in databases including Cochrane Central Register of Controlled Trials, PubMed, Embase, Cumulative Index to Nursing and Allied Health Literature for publications available till December 2019 without limitation in study type, and followed by a secondary retrieval for related literature. STATA15.1 and WinBugs 14.3 were used in statistical analyses for different sedation depths as the intervention. The main endpoint was delirium occurrence. Secondary endpoints were agitation-related adverse events and mortality.

Results

We included 18 studies comprising 8001 mechanically ventilated patients. Different sedation depths were not associated with the occurrence of delirium (OR = 1.00, 95%CI: 0.64–1.58, P = 0.993). Among the 18 enrolled studies, this finding was not confounded by the dosage of benzodiazepines (OR = 0.96, 95%CI: 0.79–1.17, P = 0.717) in eight randomized controlled trials(RCTs) or the patients’ disease severity(OR 0.95, 95%CI: 0.79–1.13, P = 0.548) in 10 RCTs. However, contrasting results were found in non-RCTs. The deeper sedation group had a significantly increased risk for death(OR = 1.82, 95% CI: 1.23–2.69, P = 0.003), whereas lighter sedation seemed a potential risk for agitation-related adverse events (OR = 0.61, 95%CI: 0.45–0.84, P = 0.002).

Conclusions

It is inconclusive whether significantly different sedation depths would change the risk of delirium in adult mechanically ventilated patients.

Trial registration number

The study was registered in PROSPERO(http://www.crd.york.ac.uk/PROSPERO/) under registration number CRD42019145276.

Postoperative anaemia might be a risk factor for postoperative delirium and prolonged hospital stay: A secondary analysis of a prospective cohort study

BACKGROUND

Postoperative anaemia is a frequent surgical complication and in contrast to preoperative anaemia has not been validated in relation to mortality, morbidity and its associated health economic effect. Postoperative anaemia can predispose postoperative delirium through impairment of cerebral oxygenation. The aim of this secondary analysis is to investigate the association of postoperative anaemia in accordance with the sex specific World Health Organization definition of anaemia to postoperative delirium and its impact on the duration of hospital stay.

METHODS

A secondary analysis of the prospective multicentric observational CESARO-study was conducted. 800 adult patients undergoing elective surgery were enrolled from various operative disciplines across seven hospitals ranging from university hospitals, district general hospitals to specialist clinics of minimally invasive surgery in Germany. Patients were classified as anaemic according to the World Health Organization parameters, setting the haemoglobin level cut off below 12g/dl for females and below 13g/dl for males. Focus of the investigation were patients with acute anaemia. Patients with present preoperative anaemia or missing haemoglobin measurement were excluded from the sample set. Delirium screening was established postoperatively for at least 24 hours and up to three days, applying the validated Nursing Delirium Screening Scale.

RESULTS

The initial sample set contained 800 patients of which 183 were suitable for analysis in the study. Ninety out of 183 (49.2%) suffered from postoperative anaemia. Ten out of 93 (10.9%) patients without postoperative anaemia developed a postoperative delirium. In the group with postoperative anaemia, 28 (38.4%) out of 90 patients suffered from postoperative delirium (odds ratio 3.949, 95% confidence interval, (1.358-11.480)) after adjustment for NYHA-stadium, severity of surgery, cutting/suture time, duration of anaesthesia, transfusion of packed red cells and sedation status with Richmond Agitation Scale after surgery. Additionally, patients who suffered from postoperative anaemia showed a significantly longer duration of hospitalisation (7.75 vs. 12.42 days, odds ratio = 1.186, 95% confidence interval, 1.083-1.299, after adjustments).

CONCLUSION

The study results reveal that postoperative anaemia is not only a frequent postsurgical complication with an incidence probability of almost 50%, but could also be associated with a postoperative delirium and a prolonged hospitalisation.

Orthopedic Surgery Triggers Attention Deficits in a Delirium-Like Mouse Model

Postoperative delirium is a frequent and debilitating complication, especially amongst high risk procedures such as orthopedic surgery, and its pathogenesis remains unclear. Inattention is often reported in the clinical diagnosis of delirium, however limited attempts have been made to study this cognitive domain in preclinical models. Here we implemented the 5-choice serial reaction time task (5-CSRTT) to evaluate attention in a clinically relevant mouse model following orthopedic surgery. The 5-CSRTT showed a time-dependent impairment in the number of responses made by the mice acutely after orthopedic surgery, with maximum impairment at 24 h and returning to pre-surgical performance by day 5. Similarly, the latency to the response was also delayed during this time period but returned to pre-surgical levels within several days. While correct responses decreased following surgery, the accuracy of the response (e.g., selection of the correct nose-poke) remained relatively unchanged. In a separate cohort we evaluated neuroinflammation and blood-brain barrier (BBB) dysfunction using clarified brain tissue with light-sheet microscopy. CLARITY revealed significant changes in microglial morphology and impaired astrocytic-tight junction interactions using high-resolution 3D reconstructions of the neurovascular unit. Deposition of IgG, fibrinogen, and autophagy markers (TFEB and LAMP1) were also altered in the hippocampus 24 h after surgery. Together, these results provide translational evidence for the role of peripheral surgery contributing to delirium-like behavior and disrupted neuroimmunity in adult mice.

Current Pharmacotherapy Does Not Improve Severity of Hypoactive Delirium in Patients with Advanced Cancer: Pharmacological Audit Study of Safety and Efficacy in Real World (Phase-R)

BACKGROUND

Pharmacotherapy is generally recommended to treat patients with delirium. We sought to describe the current practice, effectiveness, and adverse effects of pharmacotherapy for hypoactive delirium in patients with advanced cancer, and to explore predictors of the deterioration of delirium symptoms after starting pharmacotherapy.

SUBJECTS, MATERIALS, AND METHODS

We included data of patients with advanced cancer who were diagnosed with hypoactive delirium and received pharmacotherapy for treatment of delirium. This was a pharmacovigilance study characterized by prospective registries and systematic data-recording using internet technology, conducted among 38 palliative care teams and/or units. The severity of delirium and other outcomes were assessed using established measures at days 0 (T0), 3 (T1), and 7 (T2).

RESULTS

Available data were obtained from 218 patients. The most frequently used agent was haloperidol (37%). A total of 67 and 42 patients (31% and 19%) had died or discontinued pharmacotherapy by T1 and T2, respectively. Delirium symptoms deteriorated between T0 and T1, but this trend did not reach statistical significance. The most prevalent adverse event was sedation (9%). Delirium severity worsened after starting pharmacotherapy in 121 patients (56%) at T1. In patients whose death was expected within a few days and those with delirium caused by organ failure, symptoms of delirium were significantly more likely to deteriorate after starting pharmacotherapy.

CONCLUSION

Current pharmacotherapy for hypoactive delirium in patients with advanced cancer is not recommended, especially in those whose death is expected within a few days and in those with delirium caused by organ failure.

IMPLICATIONS FOR PRACTICE

Delirium is common among patients with advanced cancer, and hypoactive delirium is the dominant motor subtype in the palliative care setting. Pharmacotherapy is recommended and regularly used to treat delirium. This article describes the effectiveness and adverse effects of pharmacotherapy for hypoactive delirium in patients with advanced cancer. The findings of this study do not support the use of pharmacotherapy for treatment of hypoactive delirium in the palliative care setting. Pharmacotherapy should especially be avoided in patients whose death is expected within a few days and in those with delirium caused by organ failure.

Disruption of the ascending arousal system and cortical attention networks in post-stroke delirium and spatial neglect

Delirium is an acute attention and cognitive dysfunction, adversely affecting functional outcomes and mortality. As many as half of hospitalized right brain stroke survivors may develop delirium. Further, about 50% of right stroke patients experience spatial neglect, impairing safety and recovery. In this review we explore the brain mechanisms, which may explain the high incidence of delirium and spatial neglect after right-brain stroke. We suggest that brain networks for spatial attention and arousal, composed of ascending projections from the midbrain nuclei and integrating dorsal and ventral cortical and limbic components, may underlie impairments in delirium and spatial neglect. We propose that lateralized deficits in spatial neglect may arise because cortical and limbic components of these functional networks are disproportionally impaired by right-brain strokes, and that spatial neglect may lower the threshold for developing delirium. An improved understanding of the brain basis of delirium and spatial neglect could provide a critical biomarker for initiating preventive care in stroke patients at high risk of hospital morbidity and loss of independence.

Advance Directives, Hospitalization, and Survival Among Advanced Cancer Patients with Delirium Presenting to the Emergency Department: A Prospective Study

BACKGROUND

To improve the management of advanced cancer patients with delirium in an emergency department (ED) setting, we compared outcomes between patients with delirium positively diagnosed by both the Confusion Assessment Method (CAM) and Memorial Delirium Assessment Scale (MDAS), or group A (n = 22); by the MDAS only, or group B (n = 22); and by neither CAM nor MDAS, or group C (n = 199).

MATERIALS AND METHODS

In an oncologic ED, we assessed 243 randomly selected advanced cancer patients for delirium using the CAM and the MDAS and for presence of advance directives. Outcomes extracted from patients' medical records included hospital and intensive care unit admission rate and overall survival (OS).

RESULTS

Hospitalization rates were 82%, 77%, and 49% for groups A, B, and C, respectively (p = .0013). Intensive care unit rates were 18%, 14%, and 2% for groups A, B, and C, respectively (p = .0004). Percentages with advance directives were 52%, 27%, and 43% for groups A, B, and C, respectively (p = .2247). Median OS was 1.23 months (95% confidence interval [CI] 0.46-3.55) for group A, 4.70 months (95% CI 0.89-7.85) for group B, and 10.45 months (95% CI 7.46-14.82) for group C. Overall survival did not differ significantly between groups A and B (p = .6392), but OS in group C exceeded those of the other groups (p < .0001 each).

CONCLUSION

Delirium assessed by either CAM or MDAS was associated with worse survival and more hospitalization in patients with advanced cancer in an oncologic ED. Many advanced cancer patients with delirium in ED lack advance directives. Delirium should be assessed regularly and should trigger discussion of goals of care and advance directives.

IMPLICATIONS FOR PRACTICE

Delirium is a devastating condition among advanced cancer patients. Early diagnosis in the emergency department (ED) should improve management of this life-threatening condition. However, delirium is frequently missed by ED clinicians, and the outcome of patients with delirium is unknown. This study finds that delirium assessed by the Confusion Assessment Method or the Memorial Delirium Assessment Scale is associated with poor survival and more hospitalization among advanced cancer patients visiting the ED of a major cancer center, many of whom lack advance directives. Therefore, delirium in ED patients with cancer should trigger discussion about advance directives.

Association of Delirium With Cognitive Decline in Late Life: A Neuropathologic Study of 3 Population-Based Cohort Studies

IMPORTANCE

Delirium is associated with accelerated cognitive decline. The pathologic substrates of this association are not yet known, that is, whether they are the same as those associated with dementia, are independent, or are interrelated.

OBJECTIVE

To examine whether the accelerated cognitive decline observed after delirium is independent of the pathologic processes of classic dementia.

DESIGN, SETTING, AND PARTICIPANTS

Harmonized data from 987 individual brain donors from 3 observational cohort studies with population-based sampling (Vantaa 85+, Cambridge City Over-75s Cohort, Cognitive Function and Ageing Study) performed from January 1, 1985, through December 31, 2011, with a median follow-up of 5.2 years until death, were used in this study. Neuropathologic assessments were performed with investigators masked to clinical data. Data analysis was performed from January 1, 2012, through December 31, 2013. Clinical characteristics of brain donors were not different from the rest of the cohort. Outcome ascertainment was complete given that the participants were brain donors.

EXPOSURES

Delirium (never vs ever) and pathologic burden of neurofibrillary tangles, amyloid plaques, vascular lesions, and Lewy bodies. Effects modeled using random-effects linear regression and interactions between delirium and pathologic burden were assessed.

OUTCOMES

Change in Mini-Mental State Examination (MMSE) scores during the 6 years before death.

RESULTS

There were 987 participants (290 from Vantaa 85+, 241 from the Cambridge City Over-75s Cohort, and 456 from the Cognitive Function and Ageing Study) with neuropathologic data; mean (SD) age at death was 90 (6.4) years, including 682 women (69%). The mean MMSE score 6 years before death was 24.7 points. The 279 individuals with delirium (75% women) had worse initial scores (-2.8 points; 95% CI, -4.5 to -1.0; P < .001). Cognitive decline attributable to delirium was -0.37 MMSE points per year (95% CI, -0.60 to -0.13; P < .001). Decline attributable to the pathologic processes of dementia was -0.39 MMSE points per year (95% CI, -0.57 to -0.22; P < .001). However, the combination of delirium and the pathologic processes of dementia resulted in the greatest decline, in which the interaction contributed an additional -0.16 MMSE points per year (95% CI, -0.29 to -0.03; P = .01). The multiplicative nature of these variables resulted in individuals with delirium and the pathologic processes of dementia declining 0.72 MMSE points per year faster than age-, sex-, and educational level-matched controls.

CONCLUSIONS AND RELEVANCE

Delirium in the presence of the pathologic processes of dementia is associated with accelerated cognitive decline beyond that expected for delirium or the pathologic process itself. These findings suggest that additional unmeasured pathologic processes specifically relate to delirium. Age-related cognitive decline has many contributors, and these findings at the population level support a role for delirium acting independently and multiplicatively to the pathologic processes of classic dementia.

Delirium in advanced age and dementia: A prolonged refractory course of delirium and lower functional status

OBJECTIVE

The factors associated with persistent delirium, in contrast to resolved delirium, have not been studied well. The aim of our present study was to identify the factors associated with delirium resolution as measured by the Memorial Delirium Assessment Scale (MDAS) and functional improvement as measured by the Karnofsky Performance Status (KPS) scale.

METHOD

All subjects were recruited from psychiatric referrals at the Memorial Sloan Kettering Cancer Center (MSKCC). The two study instruments were performed at baseline (T1), at 2-3 days (T2), and at 4-7 days (T3). Subjects with persistent delirium were compared to those with resolved delirium in respect to sociodemographic and medical variables.

RESULTS

Overall, 26 out of 111 patients had persistent delirium. These patients were older, predominantly male, and had more frequently preexisting comorbid dementia. Among cancer diagnoses and stage of illness, brain cancer and terminal illness contributed to persistent delirium or late response, whereas gastrointestinal cancer was associated with resolved delirium. Among etiologies, infection responded late to delirium management, usually at one week. Furthermore, delirium was more severe in patients with persistent delirium from baseline through one week. At baseline, MDAS scores were 20.1 in persistent delirium compared to 17 to 18.8 in resolved delirium (T2 and T3), and at one week of management (T3), MDAS scores were 15.2 and 4.7 to 7.4, respectively. At one week of management, persistent delirium manifested in more severe impairment in the domains of consciousness, cognition, organization, perception, psychomotor behavior, and sleep-wake cycle. In addition, persistent delirium caused more severe functional impairment.

SIGNIFICANCE OF RESULTS

In this delirium sample, advanced age and preexisting dementia, as well as brain cancer, terminal illness, infection, and delirium severity contributed to persistent delirium or late response, indicating a prolonged and refractory course of delirium, in addition to more severe functional impairment through one week of management.

Delirium and other clinical factors with Clostridium difficile infection that predict mortality in hospitalized patients

BACKGROUND

Clostridium difficile infection (CDI) severity has increased, especially among hospitalized older adults. We evaluated clinical factors to predict mortality after CDI.

METHODS

We collected data from inpatients diagnosed with CDI at a U.S. academic medical center (HSR-IRB#13630). We evaluated age, Charlson comorbidity index (CCI), whether patients were admitted from a long-term care facility, whether patients were in an intensive care unit (ICU) at the time of diagnosis, white blood cell count (WBC), blood urea nitrogen (BUN), low body mass index, and delirium as possible predictors. A parsimonious predictive model was chosen using the Akaike information criterion (AIC) and a best subsets model selection algorithm. The area under the receiver operating characteristic curve was used to assess the model's comparative, with the AIC as the selection criterion for all subsets to measure fit and control for overfitting.

RESULTS

From the 362 subjects, the selected model included CCI, WBC, BUN, ICU, and delirium. The logistic regression coefficients were converted to a points scale and calibrated so that each unit on the CCI contributed 2 points, ICU admission contributed 5 points, each unit of WBC (natural log scale) contributed 3 points, each unit of BUN contributed 5 points, and delirium contributed 11 points.Our model shows substantial ability to predict short-term mortality in patients hospitalized with CDI.

CONCLUSION

Patients who were diagnosed in the ICU and developed delirium are at the highest risk for dying within 30 days of CDI diagnosis.

The impact of lymphopenia on delirium in ICU patients

Background

Immunosuppressed states may predispose patients to development of acute brain injury during times of critical illness. Lymphopenia is a non-specific yet commonly used bedside marker of immunosuppressed states.

Methods

We examined whether lymphopenia would predict development of acute brain dysfunction (delirium and/or coma) in 518 patients enrolled in the Bringing to Light the Risk Factors and Incidence of Neuropsychological Dysfunction in ICU Survivors (BRAIN-ICU) study in medical and surgical ICUs of a tertiary care, university-based medical center. Utilizing proportional odds logistic regression and Cox proportional hazards survival analysis, we assessed the relationship between pre-enrollment lymphocytes and subsequent cognitive outcomes including delirium- and coma-free days (DCFDs) and 30-day mortality.

Results

There were no statistically significant associations between lymphocytes and DCFDs (p = 0.17); additionally, the relationship between lymphocytes and mortality was not statistically significant (p = 0.71). Among 259 patients without history of cancer or diabetes, there was no statistically significant association between lymphocytes and DCFDs (p = 0.07).

Conclusion

lymphopenia, a commonly used bedside marker of immunosuppression, does not appear to be a marker of risk for acute brain injury (delirium/coma) or 30-day mortality in general medical/surgical ICU patients.

Preoperative plasma leptin levels predict delirium in elderly patients after hip fracture surgery

Leptin is considered to be a modulator of the immune response. Hypoleptinemia increases the risk for Alzheimer's disease and vascular dementia. The present study aimed to investigate the ability of plasma leptin level to predict delirium in elderly patients after hip fracture surgery. Postoperative delirium (pod) was evaluated using the Confusion Assessment Method. Prolonged postoperative delirium (ppod) was defined as delirium lasting more than 4 weeks. Plasma leptin levels of 186 elderly patients and 186 elderly controls were measured by an enzyme-linked immunosorbent assay. Plasma leptin level was substantially lower in patients than in controls (4.6±2.2ng/ml vs. 7.5±1.8ng/ml, P<0.001). It was identified as an independent predictor for pod [odds ratio, 0.385; 95% confidence interval (CI), 0.286-0.517; P<0.001] and ppod (odds ratio, 0.283; 95% CI, 0.152-0.527; P<0.001) using a multivariate analysis, and had high area under receiver operating characteristic curve for pod [area under curve (AUC), 0.850; 95% CI, 0.790-0.898] and ppod (AUC, 0.890; 95% CI, 0.836-0.931). The predictive value of leptin was markedly bigger than that of age for pod (AUC, 0.705; 95% CI, 0.634-0.770; P=0.002) and ppod (AUC, 0.713; 95% CI, 0.642-0.777; P=0.019). In a combined logistic-regression model, leptin improved the AUC of age to 0.890 (95% CI, 0.836-0.931) (P<0.001) for pod and 0.910 (95% CI, 0.860-0.947) (P=0.005) for ppod. Thus, preoperative plasma leptin level may be a useful, complementary tool to predict delirium and also prolonged delirium in elderly patients after hip fracture surgery.

The immunology of delirium

Delirium is an acute neuropsychiatric syndrome characterized by acute-onset global cognitive deficits, perceptual and behavioural disturbances affecting mainly elderly subjects with underlying medical or surgical conditions. The pathophysiology of delirium is complex and inflammation is a relevant precipitant factor of this syndrome, although it remains unclear how acute systemic inflammation induces the clinical picture of delirium. The central nervous system is able to detect peripheral infection or tissue destruction through circulating immune mediators and neural ascending signs. Activated microglia is responsible for an acute neuroinflammatory reaction underlying the symptoms of sickness. In healthy conditions descending pathways from the paraventricular nucleus, locus coeruleus and dorsal motor nucleus organize a centralized response to influence the immune response at the periphery and restore homeostasis. In the context of ageing and chronic neurodegeneration, adaptive changes to acute insults are characterized by exaggerated production of pro-inflammatory cytokines by primed microglia coupled with dysfunction of brain-to-immune pathways. In animal models, these changes underlie a more severe manifestation of sickness behaviour with working memory deficits suggesting that inattention, a core feature of delirium, can be a clinical correlate of an increased neuroinflammatory reaction. In patients with delirium, higher levels of pro-inflammatory cytokines and cortisol were identified in plasma and cerebrospinal fluid. However, to date it has not been clarified how peripheral inflammatory or endocrine biomarkers can reflect the likelihood or severity of delirium symptoms. In the future, a better understanding of the interaction between the brain and peripheral organs and the exact mechanism by which systemic inflammation can lead to delirium, will allow the development of new therapeutic agents.

New horizons in the pathogenesis, assessment and management of delirium

Delirium is one of the foremost unmet medical needs in healthcare. It affects one in eight hospitalised patients and is associated with multiple adverse outcomes including increased length of stay, new institutionalisation, and considerable patient distress. Recent studies also show that delirium strongly predicts future new-onset dementia, as well as accelerating existing dementia. The importance of delirium is now increasingly being recognised, with a growing research base, new professional international organisations, increased interest from policymakers, and greater prominence of delirium in educational and audit programmes. Nevertheless, the field faces several complex research and clinical challenges. In this article we focus on selected areas of recent progress and/or uncertainty in delirium research and practice. (i) Pathogenesis: recent studies in animal models using peripheral inflammatory stimuli have begun to suggest mechanisms underlying the delirium syndrome as well as its link with dementia. A growing body of blood and cerebrospinal fluid studies in humans have implicated inflammatory and stress mediators. (ii) Prevention: delirium prevention is effective in the context of research studies, but there are several unresolved issues, including what components should be included, the role of prophylactic drugs, and the overlap with general best care for hospitalised older people. (iii) Assessment: though there are several instruments for delirium screening and assessment, detection rates remain dismal. There are no clear solutions but routine screening embedded into clinical practice, and the development of new rapid screening instruments, offer potential. (iv) Management: studies are difficult given the heterogeneity of delirium and currently expert and comprehensive clinical care remains the main recommendation. Future studies may address the role of drugs for specific elements of delirium. In summary, though facing many challenges, the field continues to make progress, with several promising lines of enquiry and an expanding base of interest among researchers, clinicians and policymakers.

Delirium in hospitalized patients: implications of current evidence on clinical practice and future avenues for research--a systematic evidence review

BACKGROUND

Despite the significant burden of delirium among hospitalized adults, critical appraisal of systematic data on delirium diagnosis, pathophysiology, treatment, prevention, and outcomes is lacking.

PURPOSE

To provide evidence-based recommendations for delirium care to practitioners, and identify gaps in delirium research.

DATA SOURCES

Medline, PubMed, the Cochrane Library, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) information systems from January 1966 to April 2011.

STUDY SELECTION

All published systematic evidence reviews (SERs) on delirium were evaluated.

DATA EXTRACTION

Three reviewers independently extracted the data regarding delirium risk factors, diagnosis, prevention, treatment, and outcomes, and critically appraised each SER as good, fair, or poor using the United States Preventive Services Task Force criteria.

DATA SYNTHESIS

Twenty-two SERs graded as good or fair provided the data. Age, cognitive impairment, depression, anticholinergic drugs, and lorazepam use were associated with an increased risk for developing delirium. The Confusion Assessment Method (CAM) is reliable for delirium diagnosis outside of the intensive care unit. Multicomponent nonpharmacological interventions are effective in reducing delirium incidence in elderly medical patients. Low-dose haloperidol has similar efficacy as atypical antipsychotics for treating delirium. Delirium is associated with poor outcomes independent of age, severity of illness, or dementia.

CONCLUSION

Delirium is an acute, preventable medical condition with short- and long-term negative effects on a patient's cognitive and functional states.

Neuroinflammation in delirium: a postmortem case-control study

BACKGROUND

Delirium can be hypothesized to be an extreme manifestation of sickness behavior in elderly persons with neurodegenerative disease. The purpose of this study was to investigate whether increased cerebral inflammation with microglial, astrocyte, and cytokine activation exists in patients with delirium compared to nondelirious patients.

METHODS

Postmortem brain tissue from 9 cases with delirium was compared to 6 age-matched controls without delirium. Human leukocyte antigen-DR (HLA-DR) and CD68 cell count and glial fibrillary acidic protein (GFAP), interleukin-1β (IL-1β), IL-6,β-amyloid, and tau protein immunoreactivity were determined in hippocampus, frontal cortex, and white matter.

RESULTS

There were no significant differences in the patients with delirium compared to the controls with respect to age 73 versus 70.5 years (p=0.72) or dementia (22% versus 0%, p=0.22). Both markers for microglial activity showed significantly higher scores in delirium brain specimens than controls in the total brain score (HLA-DR 129 vs. 20 and CD68 30 vs. 8.5) as well as in the various brain areas separately. The immunoreactivity of astrocyte activity (GFAP) was higher in the total brain score in patients with delirium (5.2 vs. 4.0, p=0.05), but in the various brain areas this was only significant in the dentate gyrus. IL-6 immunoreactivity was higher in patients with delirium in all brain areas and IL-1β was not detectable. Coexisting infectious disease or dementia did not influence the overall results.

CONCLUSIONS

These preliminary study results show an association between human brain activity of microglia, astrocytes, and IL-6 and delirium in elderly patients and add to the accumulating evidence that inflammatory mechanisms are involved in delirium.

Systemic inflammation and delirium: important co-factors in the progression of dementia

It is widely accepted that inflammation plays some role in the progression of chronic neurodegenerative diseases such as AD (Alzheimer's disease), but its precise role remains elusive. It has been known for many years that systemic inflammatory insults can signal to the brain to induce changes in CNS (central nervous system) function, typically grouped under the syndrome of sickness behaviour. These changes are mediated via systemic and CNS cytokine and prostaglandin synthesis. When patients with dementia suffer similar systemic inflammatory insults, delirium is a frequent consequence. This profound and acute exacerbation of cognitive dysfunction is associated with poor prognosis: accelerating cognitive decline and shortening time to permanent institutionalization and death. Therefore a better understanding of how delirium occurs during dementia and how these episodes impact on existing neurodegeneration are now important priorities. The current review summarizes the relationship between dementia, systemic inflammation and episodes of delirium and addresses the basic scientific approaches currently being pursued with respect to understanding acute cognitive dysfunction during aging and dementia. In addition, despite there being limited studies on this subject, it is becoming increasingly clear that infections and other systemic inflammatory conditions do increase the risk of AD and accelerate the progression of established dementia. These data suggest that systemic inflammation is a major contributor to the progression of dementia and constitutes an important clinical target.

Delirium: a neurologist's view--the neurology of agitation and overactivity

Delirium is a term used variously to characterize a change in behavior. Neurologists most often use the term to describe a patient who has acutely developed a hyperactive agitated state. In many patients, agitation and overactivity are explained by toxic and metabolic factors and infections. Lesions, especially strokes, in some brain regions have been reported to cause sudden agitation and a hyperactive state, often with an increased amount of speech output, the topics of which flit from one subject to another. Strokes and other lesions that involve the temporal lobes, fusiform and lingual gyri, caudate nucleus, and anterior cingulum have been reported to cause an acute hyperactive state similar to that found in patients with delirium tremens related to alcohol withdrawal.

[Delirium--not only psychiatric issue]

Delirium presents as a diagnosis joining closely other medical disciplines. Because of its serious prognosis, precise causal diagnostic is required. Selective therapy, to avoid serious prognosis, is possible when delirium is early diagnosed and ethiology is established. The present work is to remind risk factors of delirium, to explain mechanisms responsible for development of delirium based on various etiology, show biomarkers helpful in making diagnosis, and pay special attention to prodromal symptoms and clinical forms.

Isoflurane-induced apoptosis: a potential pathogenic link between delirium and dementia

BACKGROUND

Dementia and delirium have been postulated to share common pathophysiologic mechanisms; however, identification of these unifying mechanisms has remained elusive. The inhalation anesthetic isoflurane has been shown to enhance beta-amyloid protein (Abeta) oligomerization and generation, to potentiate the cytotoxicity of Abeta, and to induce apoptosis. To address the molecular mechanisms of dementia and delirium associated with anesthesia and surgery, we assessed whether the Abeta fibrillar aggregation inhibitor Congo red can attenuate isoflurane-induced caspase-3 activation in H4 human neuroglioma cells overexpressing human beta-amyloid precursor protein (APP).

METHODS

H4 human neuroglioma cells stably transfected to express human full-length wild-type APP were exposed to 2% isoflurane for 6 hours. The cells were harvested at the end of the treatment. Caspase-3 activation was measured with quantitative Western blotting.

RESULTS

We found that isoflurane induces cellular apoptosis in a dose-dependent manner, and that Congo red inhibits isoflurane-induced apoptosis in H4 human neuroglioma cells overexpressing APP. Interestingly, Congo red also inhibits staurosporine-induced apoptosis.

CONCLUSION

The demonstration that isoflurane contributes to well-described mechanisms of Alzheimer's neuropathogenesis provides a plausible link between the acute effects of anesthesia, a well-described risk factor for delirium, and the more long-term sequelae of dementia. These findings suggest that isoflurane-induced Abeta oligomerization and apoptosis may contribute to the risk of postoperative cognitive dysfunction and provide a potential pathogenic link between delirium and dementia.

[Delirium in critically ill children in a paediatric intensive care unit]

Two critically ill girls, aged 2.3 years and 3.5 years respectively, developed delirium in the Paediatric Intensive Care Unit (PICU). The first child, admitted with meningococcal meningitis and septic shock with respiratory failure, suffered from hyperactive delirium which started 2 hours post-extubation. The second child, admitted due to an exacerbation of cystic fibrosis with the threat of respiratory failure, suffered from hypoactive delirium with regression, inconsolability, dyspraxia and dysphasia. Both patients responded well to a single intravenous dose of haloperidol. Although delirium occurs in critically ill children, it often goes unrecognized, particularly in its hypoactive form. It should nevertheless be considered as a medical emergency, particularly in a PICU setting, and should be treated accordingly. Physicians are generally reluctant to consider psychopharmacological treatment of childhood delirium. Haloperidol is considered as the drug of choice, but risperidone can also be used successfully.

Consciousness and altered consciousness

The notion of consciousness in the English scientific literature denotes a global ability to consciously perform elementary and intellectual tasks, to reason, plan, judge and retrieve information as well as the awareness of these functions belonging to the self, that is, being self-aware. consciousness can also be defined as continuous awareness of the external and internal environment, of the past and the present. The meaning of consciousness is different in various languages, but it invariably includes, the conscious person is capable to learn, retrieve and use information. Disturbance or loss of consciousness in the Hungarian medical language indicates decreased alertness or arousability rather than the impairment of the complex mental ability. Awareness denotes the spiritual process of perception and analysis of stimuli from the inner and external world. Alertness is a prerequisite of awareness. Clinical observations suggest that the lesions of specific structures of the brain may lead to specific malfunction of consciousness, therefore, consciousness must be the product of neural activity. "Higher functions" of human mental ability have been ascribed to the prefrontal and parietal association cortices. The paleocerebrum, limbic system and their connections have been considered to be the center of emotions, feelings, attention, motivation and autonomic functions. Recent evidence indicates that these phylogenetically ancient structures play an important role in the processes of acquiring, storing and retrieving information. The hippocampus has a key role in regulating memory, learning, emotion and motivation. Impaired consciousness in the neurological practice is classified based on tests for conscious behavior and by analyzing the following responses: 1. elementary reactions to sensory stimuli--these are impaired in hypnoid unconsciousness, 2. intellectual reactions to cognitive stimuli--these indicate the impairment of cognitive contents in non-hypnoid unconsciousness. Obviously, disturbance of elementary reactions related to alertness and disturbance of intellectual performance overlap. In conditions with reduced ability to react to or to perceive external stimuli the cognitive disturbance of consciousness cannot fully be explored.

Dementia and delirium in 4 patients with Machado-Joseph disease

BACKGROUND

Machado-Joseph disease (MJD; spinocerebellar ataxia type 3) is a hereditary neurodegenerative disease caused by mutation of the MJD1 gene. Patients with MJD usually present with cerebellar ataxia, external ophthalmoplegia, pyramidal and extrapyramidal signs, and muscle wasting. However, it has been reported that these patients do not demonstrate dementia.

CASE DESCRIPTION

We noticed symptoms of dementia and delirium in 4 patients with MJD. The symptoms included abnormal behavior, excitation, an uncooperative attitude, crying, disorientation, slow thought processes, hallucinations, and delusions. These symptoms were observed in patients with a relatively young onset age, and after a long clinical course. In these patients, the CAG repeat length in the MJD1 gene was much longer compared with the mean repeat length found in patients with MJD. On electroencephalographical examination, they showed slow background activity, but computed tomography and magnetic resonance imaging scans showed no cerebrocortical atrophy. Neuropathological findings in 2 patients revealed a normal cortical structure on conventional morphological examination, but at immunohistochemical examination, we found abnormal staining by an antipolyglutamine antibody in the cerebrocortical neuronal nuclei.

CONCLUSIONS

Symptoms of dementia and delirium in patients with MJD could occur in the late stages, and they might be caused not by loss of cerebrocortical neurons, but by their dysfunction.

Underlying pathologies and their associations with clinical features in terminal delirium of cancer patients

Delirium is a common complication in terminally ill cancer patients. Identification of underlying pathologies and prediction of clinical features may improve effective symptom alleviation. This study aims to clarify precipitating factors and their associations with clinical features of terminal delirium. Consecutive hospice inpatients who developed delirium were prospectively evaluated following a structured protocol. Among 237 patients followed until death, 245 episodes of delirium were identified in 213 patients. Precipitating factors for delirium were disclosed in 93% of the 153 cases in which investigations were completed. Mean number of etiologies was 1.8 +/- 1.1 per patient, and two or more factors were recognized in 52%. The main pathologies identified were hepatic failure, medications, prerenal azotemia, hyperosmolality, hypoxia, disseminated intravascular coagulation, organic damage to the central nervous system, infection, and hypercalcemia. Occurrence of hyperactive delirium and the requirement for symptomatic sedation significantly correlated with hepatic failure, opioids, and steroids, while dehydration-related pathologies were significantly associated with hypoactive delirium. Complete recovery was frequently achieved in cases with medication- and hypercalcemia-induced delirium, whereas a low remission rate was related to hepatic failure, dehydration, hypoxia, and disseminated intravascular coagulation. In conclusion, standard examinations can confirm factors potentially contributing to delirium and thereby predict the severity of agitation and clinical outcomes.

Dopamine transporter mRNA in autopsy studies of chronic cocaine users

The effects of chronic cocaine abuse on transcriptional regulation of human dopamine transporter (DAT) mRNA in midbrain dopaminergic neurons was assessed by reverse transcription-polymerase chain reaction (RT-PCR). DAT/cyclophilin mRNA ratios in the substantia nigra (SN) were unchanged in cocaine overdose (CO) victims as compared to age-matched and drug-free control (CTRL) subjects. In contrast, DAT mRNA levels were decreased significantly in agitated cocaine delirium victims (67%, p<0.05). These findings demonstrate the lack of a regulatory influence by cocaine on the steady state content of DAT mRNA in cocaine abusers. In contrast, DAT gene expression was altered significantly in cocaine abusers at risk for agitated delirium.

Update on the neuropathogenesis of delirium

Delirium has been considered a syndrome of generalized dysfunction of higher cortical functions due to its breadth of symptoms and associated diffuse slowing on electroencephalogram. Advances in neuropsychiatry have revealed differences between brain regions, including the hemispheres, which may underlie the constellation of symptoms among different psychiatric disorders. For example, different neural pathways are involved in major depression and obsessive-compulsive disorder, including lateralization to one or the other hemisphere. In this article the author proposes that delirium, too, involves particular neural pathways and that lateralization to the right may be relevant. Structural and functional neuroimaging reports and recent neuropsychological studies support this lateralization. Prefrontal cortices, anterior and right thalamus, and right basilar mesial temporoparietal cortex may play a significant role in subserving delirium symptoms and may be the 'final common pathway' for delirium from a variety of etiologies. The final common pathway may be responsible for certain 'core symptoms' (disorientation, cognitive deficits, sleep-wake cycle disturbance, disorganized thinking, and language abnormalities), while other symptoms (delusions, hallucinations, illusions, and affective lability) may occur depending on the etiology causing delirium. An imbalance in the cholinergic and dopaminergic neurotransmitter systems is most commonly implicated in causing delirium, and could both account for delirium symptoms and be consistent with the neuroanatomical pathways being implicated.

Delirium associated with Joseph disease

Three Japanese patients with Joseph disease from different families developed sleep disturbance, followed by delirium at the middle to end stage. Brain CT scans of the three patients showed brainstem tegmental atrophy. EEG revealed slowing of background activity. Two necropsy cases showed degeneration of the reticular formation, raphe nuclei and locus ceruleus in the brainstem tegmentum in addition to the common pathological findings of Joseph disease. The clinicopathological correlation between the delirium and the brainstem tegmental atrophy in Joseph disease is discussed.

Subcortical structural changes in ECT-induced delirium

A prolonged (interictal) delirium was induced by electroconvulsive therapy (ECT) in 6/36 (17%) elderly depressed patients. Brain magnetic resonance imaging or brain computerized axial tomography revealed structural changes in the basal ganglia and white matter in all six patients who developed delirium. These findings are consistent with our previous work and with several lines of data that have implicated the basal ganglia and subcortical white matter in the development of delirium from other causes. These result suggest that lesions in these areas may predispose one to developing an interictal delirium during a course of ECT.

Neuropsychiatric studies of the "pellucidumsyndrom"

Twenty-nine cases with the cavum septi pellucidi were examined by the brain X-ray CT comparing with the reported cases of "Pellucidumsyndrom" in the previous literatures. As to the clinical diagnoses of the 29 cases with the cavum septi pellucidi, there is no specificity of the clinical disorder in relation to the cavum septi pellucidi. But one case had an extremely large cavum septi pellucidi showing various types of mental and neurological symptoms similar to the "Pellucidumsyndrom" described by Wilder. It is suggested that the extremely large cavum septi pellucidi of the present case may produce the neuropsychiatric symptoms according to the direct action to the neighboring regions of the cerebrum.

Manic delirium and frontal-like syndrome with paramedian infarction of the right thalamus

A disinhibition syndrome affecting speech (with logorrhoea, delirium, jokes, laughs, inappropriate comments, extraordinary confabulations), was the main manifestation of a right-sided thalamic infarct involving the dorsomedian nucleus, intralaminar nuclei and medial part of the ventral lateral nucleus. Resolution of conflicting tasks was severely impaired, suggesting frontal lobe dysfunction. These abnormalities correlated with the finding on SPECT of a marked hypoperfusion in the overlying hemisphere predominating in the frontal region. We suggest that this behavioural syndrome was produced by disconnecting the dorsomedian nucleus from the frontal lobe and limbic system.

The association between quantitative measures of dementia and of senile change in the cerebral grey matter of elderly subjects

The ageing of many populations in recent years has directed increasing attention to the social, medical and biological problems of senescence. The psychological changes associated with ageing occupy a central position in inquiries in this field. The expectation of mental disorder shows a steep increase with advancing chronological age, and beyond 75 years a large part of this increase is accounted for by disorders associated with degenerative changes in the central nervous system for which we lack remedies at the present time. Larsson et al. (1963) have estimated that the aggregate morbidity risk for these disorders up to the age of 70 is 0·4 per cent., up to age 75, 1·2 per cent. and up to age 80, 5 per cent. For higher ages estimates were probably less reliable, but the calculated risk up to the age of 90 was 5·2 per cent. In a survey of a random sample of elderly people aged 65 and over in the general population, Kay et al. (1964), found a total of 4·2 per cent. of elderly subjects to be suffering from senile dementia, 2·9 per cent. being mild cases. The condition is generally recognized as being a major cause of serious infirmity among the elderly in psychiatric, geriatric, general medical and community practice alike.