Update on the neuropathogenesis of delirium

Validation of the delirium diagnostic tool-provisional (DDT-Pro) in geriatric medical inpatients with diagnostic permutations of the 3Ds with and without delirium

OBJECTIVE

Validations of brief delirium tools have not included analysis of psychiatric disorders comorbidities or control groups. We validated the Delirium Diagnostic Tool-Provisional (DDT-Pro) in 422 geriatric inpatients with high incidence of depression and/or dementia.

METHODS

Cross-sectional study using two delirium reference standards, DSM-5-TR and Delirium Rating Scale-Revised-98 (DRS-R98). We assessed concurrent and construct DDT-Pro validity too.

RESULTS

There were 117 (27.7%) delirium cases using DDT-Pro, 104 (24.6%) per DSM-5-TR and 93 (22.0%) per DRS-R98; 133 patients (31.5%) had depression and 105 (24.9%) dementia, some comorbid with delirium. DDT-Pro accuracy (AUC under ROC curve) ranges were 88.3-95.9% vs DSM-5-TR and 92.7-95.0% vs DRS-R98 for whole sample and four diagnostic groups, without statistical differences. DDT-Pro ≤6 had the most balanced sensitivity-specificity for delirium diagnosis against both DSM-5-TR and DRS-R98 with similar specificity but higher sensitivity for DRS-R98 than DSM-5-TR delirium, with the highest values in patients with depression and dementia (≥92% sensitivity, ≥81% specificity). Positive and negative likelihood ratios support diagnostic strength. Concurrent validity was high reflected by significant correlations (p < 0.001) of DDT-Pro total and item scores with DRS-R98 and Delirium Frontal Index scores, highest in groups with comorbid depression and/or dementia. The DDT-Pro represented a single construct for delirium demonstrated by one factor with high item loadings and high internal consistency reliability of its items.

CONCLUSIONS

The DDT-Pro demonstrated strong performance metrics in general hospital elderly inpatients with preexisting depression and/or dementia, which is unique among brief delirium tools. Its optimized cutoff score was the same as in other populations.

[Polypharmacy and Delirium in the Elderly]

Polypharmacy and Delirium in the Elderly Abstract: Delirium often occurs in elderly hospitalized patients. Multimorbidity and associated polypharmacy are known risk factors for developing delirium. Moreover, delirium itself often leads to the prescription of additional drugs. This article aims to enlighten the interrelation of delirium and polypharmacy in the context of recent evidence. It also tries to show possibilities of deprescribing.

Delusions and Hallucinations Are Associated With Greater Severity of Delirium

BACKGROUND

The 3 core domains of delirium (cognitive, higher level thinking, circadian) do not include the less common noncore psychotic symptoms. However, psychosis might inform about perturbations of neural circuitry, outcomes, or suggest tailored clinical management.

OBJECTIVE

We assessed for the first time the relationships between psychosis and other characteristics of delirium in patients without confounders for delirium phenotype, such as dementia or antipsychotics treatment.

METHODS

Cross-sectional analysis of 366 adults with delirium per the Delirium Rating Scale Revised-98, whose items distinguish hallucinations and delusions from other types of misperceptions and abnormal thought content, assessed during the preceding 24 hours to capture symptom severity fluctuation. The relationship of psychosis with other delirium characteristics was assessed using bivariate comparisons and analysis of variance as appropriate for groups with no psychosis and any psychosis (hallucinations and/or delusions), and subgroups with only hallucinations, only delusions, or both. A discriminant logistic model assessed variables associated with presence of any psychotic features versus none.

RESULTS

Delirium with any psychotic features occurred in 44.5% (163 of 366). Of the 366, 119 (32.5%) had only hallucinations (Hall), 14 (3.8%) had only delusions (Del), and 30 (8.2%) had both (Both). In the psychotic group (n = 163), 73.0% were Hall, 8.6% Del, and 18.4% Both. All psychotic patient groupings had significantly greater delirium severity on the Delirium Rating Scale Revised-98. Delusions and hallucinations were discordant for occurring together. The discriminant model found increased odds of having psychosis as 3 symptom severities increased (visuospatial ability, thought process, and sleep-wake cycle) where these each represented a delirium core domain. The noncore symptom of lability of affect had high odds ratio for psychosis, while motor retardation reduced odds of psychosis in this model.

CONCLUSIONS

Consistent with prior reports, psychosis occurred in less than half of delirious patients with delusions being infrequent, and an association with affective lability was found. We are the first to report that psychotic features are a marker for more severe delirium affecting all core domains. Given that previous functional magnetic resonance imaging research found a correlation between neural network dysconnectivity with greater severity of delirium, psychotic symptoms might be a clinical marker for greater underlying cerebral cortical neural circuitry dysfunction.

Variables associated with concordance or discordance for delirium diagnosis between referring and consulting physicians at a Tertiary Hospital in Colombia: Prospective observational study

Delirium is an acute state of impaired consciousness and a medical urgency. Its broad range of alterations in mental status make diagnosis challenging. Awareness and accurate provisional diagnosis by nonpsychiatric clinicians are important for prompt management. Because delirium symptoms overlap and mimic other neuropsychiatric conditions, a referral to a consultant psychiatrist is often needed. The aim of this study was to determine the discriminating variables that are associated with concordance or discordance for a DSM-5 delirium diagnosis made by the consultation/liaison (C/L) psychiatrist as compared to the referral diagnosis/reasons given by the referring physicians for inpatients from a Tertiary Hospital in a Latin-American country. Prospective study of a cohort of 399 consecutive patients admitted to any ward of a university hospital in Medellin-Colombia and referred by a specialist physician to the C/L Psychiatry service. Analyses for diagnostic concordance used a nested sample of 140 cases diagnosed with delirium by the psychiatrist. Two multivariate logistic models were run, for delirium diagnosis concordance and discordance between the referring physician and C/L psychiatrist. The referral diagnosis was concordant with that of Psychiatry in 90/140 patients in 64.3%, with 35.7% discordance. Increasing age (OR = 1.024) and internal medicine ward (OR = 3.0) were significantly related (Wald statistic P < .05) to concordance in the multivariate analysis whose model accuracy was 68.6%. Trauma/orthopedics ward (OR = 5.7) and SARS-CoV-2 infection (OR = 3.8) were important contributors to the model fit though not significant. Accuracy of the discordance model was 70.7%, where central nervous system (CNS) disorder (OR = 6.1) and referrals from ICU (OR = 4.9), surgery (OR = 4.6), neurology/neurosurgery (OR = 5.1) and another consultant (OR = 4.7) were significantly related (Wald statistic P < .05), while metabolic/endocrine disorder (OR = 2.7) was important for model fit, but not significant. Concordance for delirium diagnosis was higher from services where education, guidelines and working relationships with C/L Psychiatry could have contributed beneficially whereas, surprisingly, CNS disorders and neurology/neurosurgery services had higher discordance, as well as the ICU. Routine use of brief sensitive delirium assessment tools such as the DDT-Pro could enhance provisional delirium diagnosis.

Repetitive Transcranial Magnetic Stimulation in Delirium: A Double-blind, Randomized, Sham-controlled, Pilot Study

INTRODUCTION

Delirium is a fatal but potentially reversible disorder of the central nervous system that imposes high costs on health systems. This study aims to evaluate the effect of intermittent theta-burst stimulation on the severity and course of delirium disorder.

METHODS

This is a double-blind, randomized, sham-controlled pilot study. The study participants were randomly allocated into the active (active intermittent theta-burst stimulation) and sham groups. The severity of delirium was assessed 15 minutes before the intervention and 15 minutes after that by the Neelon and Champagne (NEECHAM) confusion scale.

RESULTS

In the active group, total and subscale scores of NEECHAM significantly decreased after intervention (P<0.05). Although no statistical difference was found in the control group regarding the subscale scores of NEECHAM, the difference in the total scores before and after the sham intervention was statistically significant.

CONCLUSION

Carrying one session of repetitive transcranial magnetic stimulation on the left dorsolateral prefrontal cortex can reduce the delirium severity in a short period, although it will not decrease the number of delirium cases three days after the intervention.

HIGHLIGHTS

Delirium is a CNS disorder;Delirium treatment is based on pharmacological and non-pharmacological;rTMS is quasi-modern treatment of neurocognitive disorders.

PLAIN LANGUAGE SUMMARY

Delirium is fatal but reversible disorder. regarding the restrictions of routine treatments of delirium and by considering the cognition disturbances as the core symptom of delirium, and the positive effect of rTMS on cognition functions. we hypothesized that rTMS could be effective in the treatment of delirium.

Delirium in geriatric patients

Delirium is the most common acute disorder of cognitive function in older patients. Delirium is life threatening, often under-recognized, serious, and costly. The causes are multifactorial, with old age and neurocognitive disorders as the main risk factors. Etiologies are various and multifactorial, and often related to acute medical illness, adverse drug reactions, or medical complications. To date, diagnosis is clinically based, depending on the presence or absence of certain features. In view of the multifactorial etiology, multicomponent approaches seem most promising for facing patients’ needs. Pharmacological intervention, neither for prevention nor for treatment, has been proven effective unanimously. This article reviews the current clinical practice for delirium in geriatric patients, including etiology, pathophysiology, diagnosis, prognosis, treatment, prevention, and outcomes.

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

OBJECTIVE

The investigators aimed to describe delirium etiologies and clinical characteristics, as well as the relationship between COVID-19 and delirium severities, at baseline and follow-up after delirium improvement among patients with SARS-CoV-2 infection.

METHODS

A longitudinal study of 20 consecutive critically ill, delirious COVID-19 inpatients, assessed with the Charlson Comorbidity Index-Short Form (CCI-SF), COVID-19 Clinical Severity Scale (CCSS), Delirium Etiology Checklist, Delirium Motor Subtype Scale-4, and Delirium Diagnostic Tool-Provisional (DDT-Pro), was conducted. Correlational analysis of delirium severity (DDT-Pro) with each measure of clinical severity (CCI-SF and CCSS) and comparison of baseline DDT-Pro scores between patients who were living and those who were deceased at follow-up were conducted.

RESULTS

Participants were 50-90 years old (male, 75%; hypertension, 60%). The prevalence of preexisting medical comorbidities (CCI-SF) was low and not correlated with delirium severity (p=0.193). Eighteen patients were on mechanical or high-flow noninvasive ventilation at baseline in the intensive care unit (ICU; CCSS scores 2-4). Delirium severity (DDT-Pro scores 0-6) correlated with COVID-19 severity (0.459, p=0.021). Delirium motor subtype was hyperactive in 75% of patients. There were three to four etiologies for delirium in each patient, most commonly organ insufficiency (100%), systemic infection (100%), and metabolic and endocrine disturbances (95%). The baseline DDT-Pro score was ≤4 for five (25%) patients who died before the final assessment, with a trend of being lower than that for survivors (χ²=3.398, p=0.065).

CONCLUSIONS

Among inpatients with COVID-19, at least three different etiological categories were identified for delirium. ICU staff treating patients with severe cases of COVID-19 should anticipate a greater severity of delirium. Although multivariate analyses with larger study samples are needed, more severe delirium may herald greater risk of death among COVID-19 patients.

Why is delirium more frequent in the elderly?

An aging-related reduction in the brain's functional reserve may explain why delirium is more frequent in the elderly than in younger people insofar as the reserve becomes inadequate to cover the metabolic requirements that are critically increased by stressors. The aim of this paper is to review the normal aging-related changes that theoretically compromise complex mental activities, neuronal and synaptic densities, and the neurocomputational flexibility of the functional reserve. A pivotal factor is diminished connectivity, which is substantially due to the loss of synapses and should specifically affect association systems and cholinergic fibres in delirious patients. However, micro-angiopathy with impaired blood flow autoregulation, increased blood/brain barrier permeability, changes in cerebrospinal fluid dynamics, weakened mitochondrial performance, and a pro-inflammatory involution of the immune system may also jointly affect neurons and their synaptic assets, and even cause the progression of delirium to dementia regardless of the presence of co-existing plaques, tangles, or other pathological markers. On the other hand, the developmental growth in functional reserve during childhood and adolescence makes the brain increasingly resistant to delirium, and residual reserve can allow the elderly to recover. These data support the view that functional reserve is the variable that confronts stressors and governs the risk and intensity of and recovery from delirium. Although people of any age are at risk of delirium, the elderly are at greater risk because aging and age-dependent structural changes inevitably affect the brain's functional reserve.

Validation of the Delirium Diagnostic Tool-Provisional (DDT-Pro) With Medical Inpatients and Comparison With the Confusion Assessment Method Algorithm

OBJECTIVE

Delirium remains underdetected as a result of its broad constellation of symptoms and the inadequate neuropsychiatric expertise of most medical-surgical clinicians. Brief, accurate tools are needed to enhance detection.

METHODS

The authors extended validation of the Delirium Diagnostic Tool-Provisional (DDT-Pro), originally validated in a study of inpatients with traumatic brain injury for diagnosis of delirium by nonexpert clinicians, for 200 general medical inpatients in Colombia. The three structured, quantitatively rated items in DDT-Pro represent the three core delirium domains.

RESULTS

High interrater reliability between physician and nurse (0.873) administrators, internal consistency (>0.81), and content validity were found. Compared with independent reference standard diagnosis with DSM-5 or the Delirium Rating Scale-Revised-98, the area under the receiver operating characteristic (ROC) curve (global diagnostic accuracy) range was 93.8%-96.3%. ROC analysis revealed the same cutoff score (≤6) as that for the original study, with somewhat lower sensitivities of 88.0%-90.0% and specificities of 85.3%-81.2% (independent expert physician or nurse ratings). Even when rated by a trained expert physician, the original version of the Confusion Assessment Method algorithm (CAM-A) performed moderately, with lower sensitivities (61.8%-70.0%) than the DDT-Pro (88.0%-100%) and somewhat higher specificities (84.8%-95.3% versus 67.4%-86.7%), with values depending on dementia status, reference standard, and rater type. Accuracies for the DDT-Pro and CAM-A were comparable (DDT-Pro: 83.0%-87.5% versus CAM-A: 87.5%-88.5%), although lower in the dementia subgroup, especially for CAM-A. However, these tools were significantly discordant, especially in negative cases, which suggests that they do not detect diagnosis of patients in the same way.

CONCLUSIONS

The DDT-Pro had high validity and reliability in provisional delirium diagnosis by physicians and nonexpert clinicians, although further validation is warranted before widespread use can be recommended.

Validation of the Delirium Diagnostic Tool-Provisional (DDT-Pro) in a skilled nursing facility and comparison to the 4 'A's test (4AT)

OBJECTIVE

To validate the Delirium Diagnostic Tool (DDT-Pro) in a SNF and compare its performance to the 4 A's Test (4AT) in real life conditions.

METHODS

Prospective cross-sectional study of 262 consecutively admitted adults to a SNF, independently assessed by psychiatrists using DSM-5 delirium criteria and by geriatricians using the DDT-Pro (0-9 points) and 4AT (0-12 points).

RESULTS

141 (53.8%) participants had dementia and 79 (30.1%) had delirium. DDT-Pro and 4AT were moderately correlated (-0.59). Accuracies against DSM-5 diagnosis ranged from 80 to 85% and were comparable between tools regardless of dementia. Recommended delirium cutoff for the DDT-Pro (≤6) had 77.2% sensitivity, 84% specificity, and NPV = 89.5% and 4AT (≥4) had 54.4% sensitivity and 92.9% specificity, with lower specificity in the dementia subsample. DDT-Pro sensitivity increased (84.8%) at ≤7cutoff. Sensitivity and specificity of all DDT-Pro and 2/4 4AT items displayed gradients along severity levels, but two dichotomously rated 4AT items had low positivity. The tools had low concordance (p < 0.05) for delirium positivity.

CONCLUSIONS

DDT-Pro is valid to detect delirium in SNF population where simple, structured tools with high sensitivity are needed. DDT-Pro items assess the three core domains of delirium as a continuous measure and may have advantages over the 4AT.

The Nexus Between Sleep Disturbance and Delirium Among Intensive Care Patients

Sleep in intensive care is hampered due to many factors; the clinical environment itself exacerbates sleep disturbance. Research suggests that interventions aimed at improving sleep quality have produced positive effects in reducing incidences and duration of delirium. Sleep disturbance is well documented among intensive care patients; however, its prognostic impact is not fully understood. Delirium, disproportionally prevalent among intensive care patients, has significant prognostic factors related to patient outcomes, in which sleep disturbance often is present. The relationship between sleep disturbance and delirium is complex, sharing commonalities in relation to neurobiological and neurohormonal alterations, which may contribute to a bidirectional relationship.

Neurocognitive disorders in the elderly: altered functional resting-state hyperconnectivities in postoperative delirium patients

Postoperative delirium (POD) represents a confusional state during days/weeks after surgery and is particularly frequent in elderly patients. Hardly any fMRI studies were conducted to understand the underlying pathophysiology of POD patients. This prospective observational cohort study aims to examine changes of specific resting-state functional connectivity networks across different time points (pre- and 3-5 months postoperatively) in delirious patients compared to no-POD patients. Two-hundred eighty-three elderly surgical patients underwent preoperative resting-state fMRI (46 POD). One-hundred seventy-eight patients completed postoperative scans (19 POD). For functional connectivity analyses, three functional connectivity networks with seeds located in the orbitofrontal cortex (OFC), nucleus accumbens (NAcc), and hippocampus were investigated. The relationship of POD and connectivity changes between both time points (course connectivity) were examined (ANOVA). Preoperatively, delirious patients displayed hyperconnectivities across the examined functional connectivity networks. In POD patients, connectivities within NAcc and OFC networks demonstrated a decrease in course connectivity [max. F = 9.03, p = 0.003; F = 4.47, p = 0.036, resp.]. The preoperative hyperconnectivity in the three networks in the patients at risk for developing POD could possibly indicate existing compensation mechanisms for subtle brain dysfunction. The observed pathophysiology of network function in POD patients at least partially involves dopaminergic pathways.

Hyperactive delirium in patients after non-traumatic subarachnoid hemorrhage

PURPOSE

Hyperactive delirium is common after subarachnoid hemorrhage (SAH). We aimed to identify risk factors for delirium and to evaluate its impact on outcome.

METHODS

We collected daily Richmond Agitation Sedation Scale (RASS) and Intensive Care Delirium Screening Checklist (ICDSC) scores in 276 SAH patients. Hyperactive delirium was defined as ICDSC ≥4 when RASS was >0. We investigated risk factors for delirium and its association with 3-month functional outcome using generalized linear models.

RESULTS

Patients were 56 (IQR 47-67) years old and had a Hunt&Hess (H&H) grade of 3 (IQR 1-5). Sixty-five patients (24%) developed hyperactive delirium 6 (IQR 3-16) days after SAH. In multivariable analysis, mechanical ventilation>48 h (adjOR = 4.46; 95%-CI = 1.89-10.56; p = 0.001), the detection of an aneurysm (adjOR = 4.38; 95%-CI = 1.48-12.97; p = 0.008), a lower H&H grade (adjOR = 0.63; 95%-CI = 0.48-0.83; p = 0.001) and a pre-treated psychiatric disorder (adjOR = 3.17; 95%-CI = 1.14-8.83; p = 0.027) were associated with the development of delirium. Overall, delirium was not associated with worse outcome (p = 0.119). Interestingly, patients with delirium more often had a modified Rankin Scale Score (mRS) of 1-3 (77%) compared to an mRS of 0 (14%) or 4-6 (9%).

CONCLUSION

Our data indicate that hyperactive delirium is common after SAH patients and requires a certain degree of brain connectivity based ono the highest prevalence found in SAH patients with intermediate outcomes.

Melatonin for delirium prevention in hospitalized patients: A systematic review and meta-analysis

BACKGROUND AND AIMS

Melatonin, a pineal gland hormone is reported to have a protective effect against delirium. This systematic review and meta-analysis explores the effect of melatonin and melatonin receptor agonist, ramelteon on delirium prevention in adult hospitalized patients.

METHODS

Randomized Controlled trials of melatonin/ramelteon published up to May 7, 2020 were identified from MEDLINE, PREMEDLINE, Embase, PsycINFO, the Cochrane Central Register of Controlled trials, PubMed, and Google Scholar. The primary outcome was delirium incidence. The secondary outcomes were sleep quality, sedation score, sedatives requirement, delirium duration, length of hospital stay, length of Intensive Care Unit (ICU) stay, mortality and adverse events. A meta-analysis with a random-effects models was performed. Estimates were presented as Risk Ratio (RR) or Mean Differences (MD) with 95% Confidence Interval (CI).

FINDINGS

Fourteen studies with 1712 participants were included. Melatonin/ramelteon significantly reduced delirium incidence (RR 0·61, 95% CI 0·42-0·89, p 0·009) with risk reduction of 49% in surgical patients and 34% in ICU patients. Non-significant reduction was found in medical patients. Melatonin/ramelteon were associated with improvement in sleep quality, increased sedation score and lower sedatives consumption. However, they did not reduce delirium duration, length of hospital stay, length of ICU stay and mortality. Hallucinations, nightmares and gastrointestinal disorders were prevalent in melatonin group.

INTERPRETATION

Melatonin/ramelteon are associated with reduction in delirium incidence in hospitalized patients. However, this effect seems confined to surgical and ICU patients. The optimum dosage and formulation of melatonin, and treatment duration remain uncleared and open to further studies with larger sample sizes.

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.

Deciphering delirium through semantics: a selective synopsis

During the course of the more than 2000 years of its recorded history, delirium has been given a very large number of different names, including phrenitis and paraphrenitis, mania and délire maniaque, (febrile, agitated, asthenic, lethargic, reversible toxic, symptomatic, exogenous) psychosis, inattention, acute and reversible dementia and insanity, amentia and sensorial phrenosis, reversible cognitive dysfunction, paralepsia, confusion and mental confusion, disorientation, dysergasia, and incoherence. Such a wide range of names with related definitions and pathogenic hypotheses not only bears witness to the interest that delirium has aroused in clinical investigators, but also reflects the difficulties in scientifically investigating its intrinsic nature. Furthermore, these difficulties have raised doubts about making a diagnosis that may explain why its incidence is reported to be under-estimated.

Association Between Critical Care Admissions and Cognitive Trajectories in Older Adults

OBJECTIVES

Patients requiring admission to an ICU may subsequently experience cognitive decline. Our objective was to investigate longitudinal cognitive trajectories in older adults hospitalized in ICUs. We hypothesized that individuals hospitalized for critical illness develop greater cognitive decline compared with those who do not require ICU admission.

DESIGN

A retrospective cohort study using prospectively collected cognitive scores of participants enrolled in the Mayo Clinic Study of Aging and ICU admissions retrospectively ascertained from electronic medical records. A covariate-adjusted linear mixed effects model with random intercepts and slopes assessed the relationship between ICU admissions and the slope of global cognitive z scores and domains scores (memory, attention/executive, visuospatial, and language).

SETTING

ICU admissions and cognitive scores in the Mayo Clinic Study of Aging from October 1, 2004, to September 11, 2017.

PATIENTS

Nondemented participants age 50 through 91 at enrollment in the Mayo Clinic Study of Aging with an initial cognitive assessment and at least one follow-up visit.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 3,673 participants, 372 had at least one ICU admission with median (25-75th percentile) follow-up after first ICU admission of 2.5 years (1.2-4.4 yr). For global cognitive z score, admission to an ICU was associated with greater decline in scores over time compared with participants not requiring ICU admission (difference in annual slope = -0.028; 95% CI, -0.044 to -0.012; p < 0.001). ICU admission was associated with greater declines in memory (-0.029; 95% CI, -0.047 to -0.011; p = 0.002), attention/executive (-0.020; 95% CI, -0.037 to -0.004; p = 0.016), and visuospatial (-0.013; 95% CI, -0.026 to -0.001; p = 0.041) domains. ICU admissions with delirium were associated with greater declines in memory (interaction p = 0.006) and language (interaction p = 0.002) domains than ICU admissions without delirium.

CONCLUSIONS

In older adults, ICU admission was associated with greater long-term cognitive decline compared with patients without ICU admission. These findings were more pronounced in those who develop delirium while in the ICU.

The Pharmacology of Visual Hallucinations in Synucleinopathies

Visual hallucinations (VH) are commonly found in the course of synucleinopathies like Parkinson's disease and dementia with Lewy bodies. The incidence of VH in these conditions is so high that the absence of VH in the course of the disease should raise questions about the diagnosis. VH may take the form of early and simple phenomena or appear with late and complex presentations that include hallucinatory production and delusions. VH are an unmet treatment need. The review analyzes the past and recent hypotheses that are related to the underlying mechanisms of VH and then discusses their pharmacological modulation. Recent models for VH have been centered on the role played by the decoupling of the default mode network (DMN) when is released from the control of the fronto-parietal and salience networks. According to the proposed model, the process results in the perception of priors that are stored in the unconscious memory and the uncontrolled emergence of intrinsic narrative produced by the DMN. This DMN activity is triggered by the altered functioning of the thalamus and involves the dysregulated activity of the brain neurotransmitters. Historically, dopamine has been indicated as a major driver for the production of VH in synucleinopathies. In that context, nigrostriatal dysfunctions have been associated with the VH onset. The efficacy of antipsychotic compounds in VH treatment has further supported the notion of major involvement of dopamine in the production of the hallucinatory phenomena. However, more recent studies and growing evidence are also pointing toward an important role played by serotonergic and cholinergic dysfunctions. In that respect, in vivo and post-mortem studies have now proved that serotonergic impairment is often an early event in synucleinopathies. The prominent cholinergic impairment in DLB is also well established. Finally, glutamatergic and gamma aminobutyric acid (GABA)ergic modulations and changes in the overall balance between excitatory and inhibitory signaling are also contributing factors. The review provides an extensive overview of the pharmacology of VH and offers an up to date analysis of treatment options.

Understanding Central Nervous System Effects of Deliriant Hallucinogenic Drugs through Experimental Animal Models

Hallucinogenic drugs potently alter human behavior and have a millennia-long history of use for medicinal and religious purposes. Interest is rapidly growing in their potential as CNS modulators and therapeutic agents for brain conditions. Antimuscarinic cholinergic drugs, such as atropine and scopolamine, induce characteristic hyperactivity and dream-like hallucinations and form a separate group of hallucinogens known as "deliriants". Although atropine and scopolamine are relatively well-studied drugs in cholinergic physiology, deliriants represent the least-studied class of hallucinogens in terms of their behavioral and neurological phenotypes. As such, novel approaches and new model organisms are needed to investigate the CNS effects of these compounds. Here, we comprehensively evaluate the preclinical effects of deliriant hallucinogens in various animal models, their mechanisms of action, and potential interplay with other signaling pathways. We also parallel experimental and clinical findings on deliriant agents and outline future directions of translational research in this field.

Delirium in the critically ill patient

Delirium is an acute and transient brain dysfunction that is characterized by disturbances in consciousness, affecting both its content (i.e., attention) and level (i.e., arousal). It affects as many as 50% of those admitted to an intensive care unit (ICU). Once believed to be an inconsequential outcome of critical illness, it is now recognized that delirium is harmful in both the short- and long-term. Despite occurring frequently in critically ill patients, delirium often goes unrecognized. Well-validated delirium screening tools, designed for use in the ICU, should be used to reliably detect delirium. The first step in delirium treatment is to identify and address potentially modifiable risk factors. Multiple trials have shown that benzodiazepines are a risk factor for delirium in a dose-dependent manner. Sedation with nonbenzodiazepine-based strategies are an effective means by which to reduce delirium. Nonpharmacologic strategies such as those which seek to reduce sensory impairment, sleep deprivation, and immobility are effective. Pharmacologic treatment with antipsychotics, though commonly used, is not supported by findings from placebo-controlled trials. Recent data support from multiple trials support the use of the "ABCDEF bundle" as a means by which to reduce delirium.

Antipsychotics for treatment of delirium in hospitalised non-ICU patients

BACKGROUND

Guidelines suggest limited and cautious use of antipsychotics for treatment of delirium where nonpharmacological interventions have failed and symptoms remain distressing or dangerous, or both. It is unclear how well these recommendations are supported by current evidence.

OBJECTIVES

Our primary objective was to assess the efficacy of antipsychotics versus nonantipsychotics or placebo on the duration of delirium in hospitalised adults. Our secondary objectives were to compare the efficacy of: 1) antipsychotics versus nonantipsychotics or placebo on delirium severity and resolution, mortality, hospital length of stay, discharge disposition, health-related quality of life, and adverse effects; and 2) atypical vs. typical antipsychotics for reducing delirium duration, severity, and resolution, hospital mortality and length of stay, discharge disposition, health-related quality of life, and adverse effects.

SEARCH METHODS

We searched MEDLINE, Embase, Cochrane EBM Reviews, CINAHL, Thomson Reuters Web of Science and the Latin American and Caribbean Health Sciences Literature (LILACS) from their respective inception dates until July 2017. We also searched the Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment Database, Web of Science ISI Proceedings, and other grey literature.

SELECTION CRITERIA

We included randomised and quasi-randomised trials comparing 1) antipsychotics to nonantipsychotics or placebo and 2) typical to atypical antipsychotics for the treatment of delirium in adult hospitalised (but not critically ill) patients.

DATA COLLECTION AND ANALYSIS

We examined titles and abstracts of identified studies to determine eligibility. We extracted data independently in duplicate. Disagreements were settled by further discussion and consensus. We used risk ratios (RR) with 95% confidence intervals (CI) as a measure of treatment effect for dichotomous outcomes, and between-group standardised mean differences (SMD) with 95% CI for continuous outcomes.

MAIN RESULTS

We included nine trials that recruited 727 participants. Four of the nine trials included a comparison of an antipsychotic to a nonantipsychotic drug or placebo and seven included a comparison of a typical to an atypical antipsychotic. The study populations included hospitalised medical, surgical, and palliative patients.No trial reported on duration of delirium. Antipsychotic treatment did not reduce delirium severity compared to nonantipsychotic drugs (standard mean difference (SMD) -1.08, 95% CI -2.55 to 0.39; four studies; 494 participants; very low-quality evidence); nor was there a difference between typical and atypical antipsychotics (SMD -0.17, 95% CI -0.37 to 0.02; seven studies; 542 participants; low-quality evidence). There was no evidence antipsychotics resolved delirium symptoms compared to nonantipsychotic drug regimens (RR 0.95, 95% CI 0.30 to 2.98; three studies; 247 participants; very low-quality evidence); nor was there a difference between typical and atypical antipsychotics (RR 1.10, 95% CI 0.79 to 1.52; five studies; 349 participants; low-quality evidence). The pooled results indicated that antipsychotics did not alter mortality compared to nonantipsychotic regimens (RR 1.29, 95% CI 0.73 to 2.27; three studies; 319 participants; low-quality evidence) nor was there a difference between typical and atypical antipsychotics (RR 1.71, 95% CI 0.82 to 3.35; four studies; 342 participants; low-quality evidence).No trial reported on hospital length of stay, hospital discharge disposition, or health-related quality of life. Adverse event reporting was limited and measured with inconsistent methods; in those reporting events, the number of events were low. No trial reported on physical restraint use, long-term cognitive outcomes, cerebrovascular events, or QTc prolongation (i.e. increased time in the heart's electrical cycle). Only one trial reported on arrhythmias and seizures, with no difference between typical or atypical antipsychotics. We found antipsychotics did not have a higher risk of extrapyramidal symptoms (EPS) compared to nonantipsychotic drugs (RR 1.70, 95% CI 0.04 to 65.57; three studies; 247 participants; very-low quality evidence); pooled results showed no increased risk of EPS with typical antipsychotics compared to atypical antipsychotics (RR 12.16, 95% CI 0.55 to 269.52; two studies; 198 participants; very low-quality evidence).

AUTHORS' CONCLUSIONS

There were no reported data to determine whether antipsychotics altered the duration of delirium, length of hospital stay, discharge disposition, or health-related quality of life as studies did not report on these outcomes. From the poor quality data available, we found antipsychotics did not reduce delirium severity, resolve symptoms, or alter mortality. Adverse effects were poorly or rarely reported in the trials. Extrapyramidal symptoms were not more frequent with antipsychotics compared to nonantipsychotic drug regimens, and no different for typical compared to atypical antipsychotics.

Factor Analysis of Delirium in Elderly, Using the Korean Version of Delirium Rating Scale-Revised-98

OBJECTIVE

This study aimed to identify the core symptoms of delirium, particularly in elderly people associated with major risk factors, using the Korean version of the Delirium Rating Scale-Revised-98.

METHODS

The study sample consisted of 200 patients (mean age: 72.7±3.9 years, male: 68.5%) who had been diagnosed with delirium. Exploratory factor analysis was used to investigate the factor structure, and confirmatory factor analysis was used to evaluate the goodness of fit of the results.

RESULTS

The results demonstrated three core domains of delirium in the elderly patients: 1) the cognitive domain (e.g., language, thought process, orientation, attention, long-term memory, and visuospatial ability); 2) the circadian domain (e.g., sleep-wake cycle and motor behavior); and 3) the short-term memory domain (short-term memory). These results were confirmed by confirmatory factor analysis.

CONCLUSION

The findings of this study suggest a theoretical domain structure for delirium in elderly patients.

Delirium clinical motor subtypes: a narrative review of the literature and insights from neurobiology

INTRODUCTION

Clinical motor subtypes have been long recognised in delirium and, despite a growing body of research, a lack of clarity exists regarding the importance of these motor subtypes. The aims of this review are to (1) examine how the concept of motor subtypes has evolved, (2) explore their relationship to the clinical context, (3) discuss the relationship between the phenomenology of delirium and motor activity, (4) discuss the application of neurobiology to the theory of delirium motor subtypes, and (5) identify methodological issues and provide solutions for further studies.

METHODS

The following databases were searched: PubMed, PsychInfo, EBSCO, Medline, BioMed central and Science Direct. Inclusion criteria specified peer-reviewed research assessing delirium motor subtypes published between 1990 and 2016.

RESULTS

Sixty-one studies met the inclusion criteria. The majority of studies (n = 50) were found to use validated psychometric tools, while the remainder (n = 11) used clinical criteria. The majority of studies (n = 45) were conducted in the medical setting, while the remainder were in the ICU/post-operative setting (n = 17).

CONCLUSION

Although host sensitivities (e.g. frailty) and exogenous factors (e.g. medication exposure) may determine the type of motor disturbance, it remains unclear to what extent motor subtypes are influenced by other features of delirium. The use of more specialised tools (e.g. delirium motor subtyping scale), may enable researchers to develop an approach to delirium that has a greater nosological consistency. Future studies investigating delirium motor subtypes may benefit from enhanced theoretical considerations of the dysfunctional neural substrate of the delirious state.

Mortality and Functional Disability of Poststroke Delirium

Introduction

Small number of studies have evaluated the mortality and the degree of functional disability of post-stroke delirium, and our aim was to determine that.

Patients and Methods

Comprehensive neuropsychological assessments were performed within the first week of stroke onset, at hospital discharge, and followed-up for 3, 6 and 12 months after stroke. We used diagnostic tools such as Glasgow Coma Scale, Delirium Rating Scale, National Institutes of Health Stroke Scale and Mini-Mental State.

Results

Delirious patients had a significantly higher mortality (p = 0.0005). As opposed to the type of stroke mortality was higher after ischemic (p = 0.0005). The patients without delirium had significantly better cumulative survival during the first year after stroke (p = 0.0005). Delirious patients aged ≥65 years had a significantly lower cumulative survival during the first year after stroke (p = 0.0005). In relation to the type of stroke delirious patients with ischemic had a significantly lower cumulative survival during the first year after stroke (p = 0.0005). Delirious patients had a greater degree of functional impairment at discharge (p = 0.01), three (p = 0.01), six months (p = 0.01) and one year (p = 0.01) after stroke.

Conclusion

Delirious patients have a significantly higher mortality, lower cumulative survival and a greater degree of functional disability in the first year after stroke.

Acetylcholinesterase and butyrylcholinesterase in cardiosurgical patients with postoperative delirium

Background

Patients in intensive care units (ICU) are often diagnosed with postoperative delirium; the duration of which has a relevant negative impact on various clinical outcomes. Recent research found a potentially important role of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in delirium of critically ill patients on non-surgical ICU or in non-cardiac-surgery patients. We tested the hypothesis that AChE and BChE have an impact on patients after cardiac surgery with postoperative delirium.

Methods

After obtaining approval from the local ethics committee, this mechanistic study gathered data of all 217 patients included in a randomized controlled trial testing non-pharmacological modifications of care in the cardiac surgical ICU to reduce delirium.

Delirium was assessed with the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) and the Nursing Delirium Screening Scale (Nu-DESC) twice a day for the first 3 days after surgery. Further outcome variables were somatic laboratory parameters and variables regarding surgery, anesthesia, and postsurgical recovery. 10 μl venous or arterial blood was drawn and AChE and BChE were determined with ChE check mobile from Securetec.

Results

Of 217 patients, 60 (27.6%) developed postsurgical delirium (POD). Patients with POD were older (p = 0.005), had anemia (p = 0.01), and worse kidney function (p = 0.006). Furthermore, these patients had lower intraoperative cerebral saturation (NIRS) (p < 0.001) and higher intraoperative need of catecholamines (p = 0.03). Delirious patients showed more inflammatory response (p < 0.001). AChE and BChE values were mainly inside the norm. Patients with values outside the norm did not have POD more often than others. Regarding AChE and BChE patients did not differ in having delirium or not (p > 0.10).

Conclusions

Postoperative measurement of AChE and BChE did not discern between patients with and without POD. The effect of the cardiac surgical procedure on AChE and BChE remains unclear. Further studies with patients in cardiac surgery are needed to evaluate a possible combination of delirium and the cholinergic transmitter system. There might be possible interactions with AChE/BChE and blood products and the use of cardiopulmonary bypass, which should be investigated more intensively.

Trial registration

German Clinical Trials Register, DRKS00006217

The role of predictive coding in the pathogenesis of delirium

Delirium and dementia represent an emerging global crisis in healthcare. Attempts have been made to identify the pathognomonic feature that would make delirium stand out from dementia but unfortunately the global neural dysfunction of both disorders has made the establishment of a direct measurement difficult. Modern conceptualisations of delirium have been influenced by the assessment tools used to assess, detect, and analyse its complex and transient nature. Recent publication of the DSM-V criteria for delirium has marginally altered the previous DSM-IV criteria with a focus upon inattention with vague terms such as consciousness downplayed. Such an alteration has been found to be restrictive and thus impact upon delirium case identification. Although these findings are approximating the empirical state of delirium as measured by validated instruments, a more refined neuroscientifically informed phenomenological framework is required in order to enhance the theoretical understanding of delirium assessment and resolve these challenges. One such application is the predictive coding (PC) model, also known as the hierarchical Bayesian inference model, to interpreting delirium pathophysiology. Therefore, the aims of this paper are to 1) propose the hypothesis that delirium pathophysiology can be explained in terms of the PC model, 2) support this hypothesis by applying this model to current methods of assessing delirium phenomenology, particularly attention, and 3) outline a future programme of research to test many of the parameters of this application.

Delirium in critically ill patients

Delirium is common in critically ill patients and associated with increased length of stay in the intensive care unit (ICU) and long-term cognitive impairment. The pathophysiology of delirium has been explained by neuroinflammation, an aberrant stress response, neurotransmitter imbalances, and neuronal network alterations. Delirium develops mostly in vulnerable patients (e.g., elderly and cognitively impaired) in the throes of a critical illness. Delirium is by definition due to an underlying condition and can be identified at ICU admission using prediction models. Treatment of delirium can be improved with frequent monitoring, as early detection and subsequent treatment of the underlying condition can improve outcome. Cautious use or avoidance of benzodiazepines may reduce the likelihood of developing delirium. Nonpharmacologic strategies with early mobilization, reducing causes for sleep deprivation, and reorientation measures may be effective in the prevention of delirium. Antipsychotics are effective in treating hallucinations and agitation, but do not reduce the duration of delirium. Combined pain, agitation, and delirium protocols seem to improve the outcome of critically ill patients and may reduce delirium incidence.

PREDICTORS FOR POST- STROKE DELIRIUM OUTCOME

BACKGROUND

There have been only a small number of studies that have evaluated the outcome of post-stroke delirium.

OBJECTIVES

To evaluate the effects of gender, age, stroke localization, delirium severity, previous illnesses, associated medical complications on delirium outcome as well as, to determine effects of delirium on cognitive functioning one year after stroke.

PATIENTS AND METHODS

Comprehensive neuropsychological assessments were performed within the first week of stroke onset, at hospital discharge, and followed-up for 3, 6 and 12 months after stroke. We used diagnostic tools such as Glazgow Coma Scale, Delirium Rating Scale, National Institutes of Health Stroke Scale and Mini-Mental State.

RESULTS

Patients who developed post-stroke delirium had significantly more complications (p = 0.0005). Direct logistic regression was performed to assess the impact of several factors on the likelihood that patients will die. The strongest predictor of outcome was age, mean age ≥ 65 years with a odds ratio (OR) 4.9. Cox's regression survival was conducted to assess the impact of multiple factors on survival. The accompanying medical complications were the strongest predictor of respondents poore outcome with Hazard-risk 3.3. Cognitive assessments including Mini Mental State score have showen that post-stroke delirium patients had significant cognitive impairment, three (p = 0.0005), six months (p = 0.0005) and one year (p = 0.0005) after stroke, compared to patients without delirium.

CONCLUSION

Patient gender, age, localization of stroke, severity of delirium, chronic diseases and emerging complications significantly affect the outcome of post- stroke delirium. Delirium significantly reduced cognitive functioning of after stroke patients.

Comparison of diagnostic classification systems for delirium with new research criteria that incorporate the three core domains

OBJECTIVE

Diagnostic classification systems do not incorporate phenomenological research findings about the three core symptom domains of delirium (Attentional/Cognitive, Circadian, Higher Level Thinking). We evaluated classification performances of novel Trzepacz, Meagher, and Franco research diagnostic criteria (TMF) that incorporate those domains and ICD-10, DSM-III-R, DSM-IV, and DSM-5.

METHODS

Primary data analysis of 641 patients with mixed neuropsychiatric profiles. Delirium (n=429) and nondelirium (n=212) reference standard groups were identified using cluster analysis of symptoms assessed using the Delirium Rating Scale-Revised-98. Accuracy, sensitivity, specificity, positive and negative predictive values (PPV, NPV), and likelihood ratios (LR+, LR-) are reported.

RESULTS

TMF criteria had high sensitivity and specificity (87.4% and 89.2%), more balanced than DSM-III-R (100% and 31.6%), DSM-IV (97.7% and 74.1%), DSM-5 (97.7% and 72.6%), and ICD-10 (66.2% and 100%). PPV of DSM-III-R, DSM-IV, and DSM-5 were <90.0%, while PPV for ICD-10 and TMF were >90%. ICD-10 had the lowest NPV (59.4%). TMF had the highest LR+ (8.06) and DSM-III-R the lowest LR- (0.0). Overall, values for DSM-IV and DSM-5 were similar, whereas for ICD-10 and DSM-III-R were inverse of each other. In the pre-existing cognitive impairment/dementia subsample (n=128), TMF retained its highest LR+ though specificity (58.3%) became less well balanced with sensitivity (87.9%), which still exceeded that of DSM.

CONCLUSIONS

TMF research diagnostic criteria performed well, with more balanced sensitivity and specificity and the highest likelihood ratio for delirium identification. Reflecting the three core domains of delirium, TMF criteria may have advantages in biological research where delineation of this syndrome is important.

"I Can Remember Sort of Vivid People…but to Me They Were Plasticine." Delusions on the Intensive Care Unit: What Do Patients Think Is Going On?

INTRODUCTION

Patients who develop intensive care unit (ICU) acquired delirium stay longer in the ICU, and hospital, and are at risk of long-term mental and physical health problems. Despite guidelines for patient assessment, risk limitation, and treatment in the ICU population, delirium and associated delusions remain a relatively common occurrence on the ICU. There is considerable information in the literature describing the incidence, suspected causes of, and discussion of the benefits and side-effects of the various treatments for delirium in the ICU. But peer-reviewed patient-focused research is almost non-existent. There is therefore a very limited understanding of the reality of delusions in the intensive care unit from the patient's point of view.

METHOD

A secondary analysis of the original interviews conducted by the University of Oxford Health Experiences Research Group was undertaken to explore themes relating specifically to sleep and delirium.

RESULTS

Patients describe a liminal existence on the ICU. On the threshold of consciousness their reality is uncertain and their sense of self is exposed. Lack of autonomy in an unfamiliar environment prompts patients to develop explanations and understandings for themselves with no foothold in fact.

CONCLUSION

Patients on the ICU are perhaps more disoriented than they appear and early psychological intervention in the form of repeated orientation whilst in the ICU might improve the patient experience and defend against development of side-effects.

Review of Postoperative Delirium in Geriatric Patients Undergoing Hip Surgery

Postoperative delirium is a serious complication following hip surgery in elderly patients that can adversely affect outcomes in both hip fracture and arthroplasty surgery. Recently, the incidence of hip fracture in the Medicare population was estimated at approximately 500 000 patients per year, with the majority treated surgically. The annual volume of total hip arthroplasty is nearly 450 000 patients and is projected to increase over the next 15 to 20 years. Subsequently, the incidence of postoperative delirium will rise. The incidence of postoperative delirium after hip surgery in the elderly patients ranges between 4% and 53%, and it is identified as the most common surgical complication of older patients. The most common risk factors include advanced age, hip fracture surgery (vs elective hip surgery), and preoperative delirium/cognitive impairment. Exact pathophysiology has not been fully defined. It is hypothesized that imbalances in cortical neurotransmitters or inflammatory cytokine pathway mechanisms contribute to delirium. Development of postoperative delirium is associated with longer hospital stay, increased medical complications, and poorer short-term functional outcome. Patients who develop postoperative delirium are also at increased risk for cognitive decline beyond the acute phase. Following acute care, postoperative delirium is associated with the need for a higher level of care, an additional cost. Management of postoperative delirium centers on prevention and early recognition. Medical prophylaxis has been demonstrated to have limited utility. Utilization of delirium detection methods contributed to early recognition. The most effective means of prevention involved a multidisciplinary team focused on adequate hydration, optimization of analgesia, reduction in polypharmacy, aggressive physiotherapy, and early recognition of the delirium symptoms.

[Delirium Prevention]

INTRODUCTION

Delirium is the most prevalent neuropsychiatric syndrome in the general hospital. Its presence is a marker of poor prognosis for patients. Its prevention could be the most effective strategy for reducing its frequency and its complications.

OBJECTIVE

To review recent findings and strategies for the prevention of delirium.

METHODOLOGY

A non-systematic review of scientific articles published in the last ten years in Spanish and English. A search was made in databases such as MEDLINE, Cochrane, EMBASE, Ovid, and ScienceDirect, for articles that included the terms, delirium and prevention.

RESULTS

Identification of predisposing and precipitating factors for delirium and a better understanding of the pathophysiological mechanisms underlying the onset of delirium have enabled the implementation of various pharmacological and non-pharmacological strategies in patients at high risk to develop hospital delirium. The studies to prevent delirium have focused on surgical patients. The current evidence supports the daily implementation of non-pharmacological measures to prevent delirium, as they are easy and cost effective. The available evidence is still limited to recommend the daily use of pharmacological strategies in delirium prophylaxis, and there is a consensus against the modest use of antipsychotic drugs in surgical patients and dexmedetomidine in patients in intensive care.

CONCLUSIONS

New high-quality clinical trials and studies involving non-surgical patients are needed to provide more evidence about this subject.

Chronic critical illness: the price of survival

BACKGROUND

The evolution of the techniques used in the intensive care setting over the past decades has led on one side to better survival rates in patients with acute conditions and severely impaired vital functions. On the other side, it has resulted in a growing number of patients who survive an acute event, but who then become dependent on one or more life support techniques. Such patients are called chronically critically ill patients.

MATERIALS & METHODS

No absolute definition of the disease is currently available, although most patients are characterized by the need for prolonged mechanical ventilation. Mortality rates are still high even after dismissal from intensive care unit (ICU) and transfer to specialized rehabilitation care settings.

RESULTS

In recent years, some studies have tried to clarify the pathophysiological characteristics underlying chronic critical illness (CCI), a disease that is also characterized by severe endocrine and inflammatory impairments, partly accounting for the almost constant set of symptoms.

DISCUSSION

Currently, no specific treatment is available. However, a strategic early therapeutic approach on ICU admission might try to prevent the progress of the acute disease towards chronic critical illness.

[Cerebral dysfunction as a component of multiple organ failure in surgical patients (lecture)]

Development of delirium in critically ill patients is considered complication of basic disease which increases patients' hospital stay, mortality rate and the cost of treatment. Despite wide prevalence delirium often remains undiagnosed by physicians in ICU. Routine use of screening scales permits to diagnose delirium timely. Multicomponent preventive strategy with intermittent sedation and dexmedetomidine improves the results of treatment.

A Case Report on Varenicline Induced Delirium in an Alcohol and Nicotine Dependent Patient

Varenicline is a smoking cessation agent. Varenicline acts as a partial agonist of α4β2 neuronal nicotinic acetylcholine receptor and prevents nicotine binding to the same. It also causes dopamine (DA) stimulation that decreases craving and symptoms of dependence. A 40-year-old male diagnosed with alcohol and nicotine dependence syndrome was treated with 1 mg of varenicline for 3 days. Patient developed episodes of transient delirium within 15-30 min after administration of varenicline. Patient was disoriented and did not respond relevantly. Patient would have disorientation and would respond irrelevantly and was unable to recall the event completely. There were no features suggestive of seizures. The episodes resolved after the medication was stopped. Varenicline, with its partial agonistic effect on nicotinergic receptors, stimulates the release of multiple neurotransmitters including DA. DA dysregulation is probably responsible for the development of neuropsychiatric adverse reactions due to varenicline. This is the first case report to the best of our knowledge reporting varenicline induced dilirium. In this case, the adverse event was found in an alcohol and nicotine dependent patient undergoing treatment. It is essential to monitor uncommon adverse effects as this can cause significant morbidity.

[Delirium: a common complication of severe pathological conditions]

Delirium is a complex syndrome caused most often by secondary neuronal dysfuncions due to systemic disorders. Because of the central nervous system manifestations of the general disease processes that are getting through the blood-brain barrier, the vigilance of attention flucutates and, therefore, the integration of incoming stimuli fails - resulting in inadequate behavioral answers. Delirium is one of the most common and serious complications of diseases, particularly in the elderly and patients in critical state. It cannot be traced back to a single etiologic process; one should consider all those pathophysiologic mechanisms that are interacting with one another simultaneously impairing the integrated functioning of the brain. Despite the high prevalence rate of delirium and the marked adverse effects on the outcome of the underlying disorders, management and therapy are basically lacking professional guidelines. The syndrome is a threatening state, requiring increased clinical attention and often intensive care. Beside evidence based therapeutic methods, conscious, targeted screening of the known risk factors and measures against them when they present themselves may exert remarkable influence on the prevention of delirium, which is also an exceptionally important aspect of the care of patients in critical state.

MMSE items that predict incident delirium and hypoactive subtype in older medical inpatients

Because hypoactive delirium is especially under-recognized, we analyzed which Mini-Mental State Examination (MMSE) items predicted incident delirium and its hypoactive motor presentation. Over a 1-year period, older medical inpatients (n=291) were consecutively screened on admission with the Confusion Assessment Method-Spanish (CAM-S) to exclude prevalent delirium. Nondelirious patients were evaluated the same day with the MMSE, followed by daily ratings with the CAM-S. Those who became CAM-S positive were rated using the Delirium Rating Scale-Revised-98 to assess severity and motor subtype. Disorientation to time (OR 4.4, 95% CI 1.7-11.1) and place (OR 3.8, 95% CI 1.7-8.2) at admission were risk factors for delirium at follow-up and together correctly classified 88.3% of subjects as to delirium status. Disorientation to time and place, and visuoconstructional impairment were each associated with either hypoactive or mixed subtype (p<0.05 χ(2) test). Simple bedside evaluation of cognitive function in nondelirious patients revealed deficits that detected patients at risk for developing incident delirium at follow-up (especially hypoactive or mixed). We recommend patients with orientation deficits be monitored closely for emergence of delirium. A separate evaluation for possible dementia or other causes of cognitive impairment at admission should be considered too.

The attributable mortality of delirium in critically ill patients: prospective cohort study

OBJECTIVE

To determine the attributable mortality caused by delirium in critically ill patients.

DESIGN

Prospective cohort study.

SETTING

32 mixed bed intensive care unit in the Netherlands, January 2011 to July 2013.

PARTICIPANTS

1112 consecutive adults admitted to an intensive care unit for a minimum of 24 hours.

EXPOSURES

Trained observers evaluated delirium daily using a validated protocol. Logistic regression and competing risks survival analyses were used to adjust for baseline variables and a marginal structural model analysis to adjust for confounding by evolution of disease severity before the onset of delirium.

MAIN OUTCOME MEASURE

Mortality during admission to an intensive care unit.

RESULTS

Among 1112 evaluated patients, 558 (50.2%) developed at least one episode of delirium, with a median duration of 3 days (interquartile range 2-7 days). Crude mortality was 94/558 (17%) in patients with delirium compared with 40/554 (7%) in patients without delirium (P<0.001). Delirium was significantly associated with mortality in the multivariable logistic regression analysis (odds ratio 1.77, 95% confidence interval 1.15 to 2.72) and survival analysis (subdistribution hazard ratio 2.08, 95% confidence interval 1.40 to 3.09). However, the association disappeared after adjustment for time varying confounders in the marginal structural model (subdistribution hazard ratio 1.19, 95% confidence interval 0.75 to 1.89). Using this approach, only 7.2% (95% confidence interval -7.5% to 19.5%) of deaths in the intensive care unit were attributable to delirium, with an absolute mortality excess in patients with delirium of 0.9% (95% confidence interval -0.9% to 2.3%) by day 30. In post hoc analyses, however, delirium that persisted for two days or more remained associated with a 2.0% (95% confidence interval 1.2% to 2.8%) absolute mortality increase. Furthermore, competing risk analysis showed that delirium of any duration was associated with a significantly reduced rate of discharge from the intensive care unit (cause specific hazard ratio 0.65, 95% confidence interval 0.55 to 0.76).

CONCLUSIONS

Overall, delirium prolongs admission in the intensive care unit but does not cause death in critically ill patients. Future studies should focus on episodes of persistent delirium and its long term sequelae rather than on acute mortality.Trial registration Clinicaltrials.gov NCT01905033.

A rare cause of hypoactive delirium

A 90-year-old man was transferred to a geriatric evaluation and management (GEM) unit for management of hypoactive delirium following a pneumonia and acute myocardial infarction complicated by septic shock. He was found to have central hypothyroidism and hypoadrenalism leading to the diagnosis of hypopituitarism. Cerebral imaging confirmed this was secondary to a pituitary haemorrhage. This case illustrates the complexity of assessment of delirium and its aetiologies. Hypoactive forms of delirium in particular can be difficult to detect and therefore remain undiagnosed. While this patient's delirium was likely multifactorial, his hypopituitary state explained much of his hypoactivity. His drowsiness, bradycardia, hypotension and electrolyte imbalance provided clinical clues to the diagnosis.

Delirium and depression: inter-relationship and clinical overlap in elderly people

Delirium and depression are complex neuropsychiatric syndromes common in the elderly and are associated with poor health-care outcomes. Accurate diagnosis is essential to the provision of optimum health care for individuals with these conditions but is complicated by substantial clinical overlap in symptoms and comorbidities. A careful assessment of the patient's symptoms, including their context and time course, is needed for accurate diagnosis. Previous depression is common in patients with delirium and depressive illness is a recognised sequelae of delirium. The two syndromes seem to be caused by similar pathophysiological mechanisms, involving disturbances in stress and inflammatory responses, monoaminergic and melatonergic signalling, which point to new avenues for therapeutic intervention. Improved methods to assess delirium and depression in populations at high risk by virtue of their age, diminished cognitive reserve and physical frailty is a key target to achieve improved health-care outcomes in elderly individuals.

Dexmedetomidine reduces the risk of delirium, agitation and confusion in critically Ill patients: a meta-analysis of randomized controlled trials

OBJECTIVES

Delirium frequently is observed in critically ill patients in the intensive care unit (ICU) and is associated strongly with a poor outcome. Dexmedetomidine seems to reduce time to extubation and ICU stay without detrimental effects on mortality. The objective of the authors' study was to evaluate the effect of this drug on delirium, agitation, and confusion in the ICU setting.

DESIGN

Meta-analysis of all the randomized clinical trials ever performed on dexmedetomidine versus any comparator in the ICU setting.

SETTING

Intensive care units.

PARTICIPANTS

Critically ill patients.

INTERVENTIONS

None

MEASUREMENTS AND MAIN RESULTS

Pertinent studies were independently searched in BioMedCentral, PubMed, Embase, and the Cochrane Central Register of clinical trials. Primary endpoint was the rate of delirium, including the adverse events, agitation and confusion. The 13 included manuscripts (14 trials) randomized 3,029 patients. Overall analysis showed that the use of dexmedetomidine was associated with significant reductions in the incidence of delirium, agitation and confusion (298/1,565 [19%] in the dexmedetomidine group v 337/1,464 [23%] in the control group, RR = 0.68 [0.49 to 0.96], p = 0.03). Results were confirmed in subanalyses performed on patients undergoing noninvasive ventilation (1/53 [2%] in the dexmedetomidine group v 7/49 [14%] in the control group, RR=0.18 [0.03 to 1.01], p = 0.05), receiving midazolam as a comparator (268/1,164 [23%] in the dexmedetomidine group v 277/1,025 [27%] in the control group, RR = 0.68 [0.47 to 1.00], p = 0.05) and in general ICU setting patients (204/688 [30%] in the dexmedetomidine group v 204/560 [36%] in the control group, RR = 0.68 [0.45 to 0.81], p < 0.01).

CONCLUSIONS

This meta-analysis of randomized controlled studies suggests that dexmedetomidine could help to reduce delirium in critically ill patients.

Role of C-reactive protein in schizophrenia: an overview

Over the years, schizophrenia is speculated to be associated with immune or inflammatory reactions mediated by cytokines. It is proposed that chronic inflammation might damage the micro-vascular system of brain and hamper cerebral blood flow. Scientific evidence suggests that an increase of stress hormone like norepinephrine may activate the inflammatory arm of the immune system and trigger the expression of genes that cause chronic, low-grade inflammation. Thus, studies were conducted to decipher the potentiality of CRP as a marker for inflammation in schizophrenia. This article reviews the findings of CRP in schizophrenia, and the limitations of the previous studies have been discussed. The importance of simultaneous study of CRP modulating cytokines and CRP gene polymorphism in the study of serum or plasma level of CRP has been emphasized.

A longitudinal study of delirium phenomenology indicates widespread neural dysfunction

OBJECTIVES

Delirium affects all higher cortical functions supporting complex information processing consistent with widespread neural network impairment. We evaluated the relative prominence of delirium symptoms throughout episodes to assess whether impaired consciousness is selectively affecting certain brain functions at different timepoints.

METHODS

Twice-weekly assessments of 100 consecutive patients with DSM-IV delirium in a palliative care unit used the Delirium Rating Scale Revised-98 (DRS-R98) and Cognitive Test for Delirium (CTD). A mixed-effects model was employed to estimate changes in severity of individual symptoms over time.

RESULTS

Mean age = 7 0.2 ± 10.5 years, 51% were male, and 27 had a comorbid dementia. A total of 323 assessments (range 2-9 per case) were conducted, but up to 6 are reported herein. Frequency and severity of individual DRS-R98 symptoms was very consistent over time even though the majority of patients (80%) experienced fluctuation in symptom severity over the course of hours or minutes. Over time, DRS-R98 items for attention (88-100%), sleep-wake cycle disturbance (90-100%), and any motor disturbance (87-100%), and CTD attention and vigilance were most frequently and consistently impaired. Mixed-effects regression modeling identified only very small magnitudes of change in individual symptoms over time, including the three core domains.

SIGNIFICANCE OF RESULTS

Attention is disproportionately impaired during the entire episode of delirium, consistent with thalamic dysfunction underlying both an impaired state of consciousness and well-known EEG slowing. All individual symptoms and three core domains remain relatively stable despite small fluctuations in symptom severity for a given day, which supports a consistent state of impaired higher cortical functions throughout an episode of delirium.

Delirium: a disturbance of circadian integrity?

Delirium is a serious neuropsychiatric syndrome of acute onset that occurs in approximately one in five general hospital patients and is associated with serious adverse outcomes that include loss of adaptive function, persistent cognitive problems and increased mortality. Recent studies indicate a three-domain model for delirium that includes generalised cognitive impairment, disturbed executive cognition, and disruption of behaviours that are under circadian control such as sleep-wake cycle and motor activity levels. As a consequence, attention has focused upon the possible role of the circadian timing system (CTS) in the pathophysiology of delirium. We explored this possibility by reviewing evidence that (1) many symptoms that occur in delirium are influenced by circadian rhythms, (2) many features of recognised circadian rhythm disorders are similar to characteristic features of delirium, (3) common risk factors for delirium are known to disrupt circadian systems, (4) physiological disturbances of circadian systems have been noted in delirious patients, and (5) positive effects in the treatment of delirium have been demonstrated for melatonin and related agents that influence the circadian timing system. A programme of future studies that can help to clarify the relevance of circadian integrity to delirium is described. Such work can provide a better understanding of the pathophysiology of delirium while also identifying opportunities for more targeted therapeutic efforts.

Incidence of cholinesterase inhibitor therapy initiation among hospitalized patients

BACKGROUND

Initiation of cholinesterase inhibitor (ChEI) therapy for delirium during hospitalization is ineffective and may be associated with increased morbidity and mortality.

OBJECTIVE

To describe the incidence of initiating ChEI therapy during hospitalization.

DESIGN

A retrospective cross-sectional study.

SETTING

A tertiary-care academic medical center.

PATIENTS

Inpatient admissions from September 2010 through March 2011 with ChEI administration.

INTERVENTION

None.

MEASUREMENTS

Incidence of ChEI exposure, initiation of ChEI therapy, initiation of antipsychotics and benzodiazepines, infection, in-hospital mortality, and hospital length of stay.

RESULTS

The incidence of adult admissions with ChEI exposure and ChEI initiation was 23.2 (95% confidence interval: 21.2-25.4) and 2 (95% confidence interval 1.5-2.8) per 1000 admissions, respectively. Of 476 admissions receiving ChEI, 9% (n = 42) initiated therapy during the hospital stay and 91% (n = 434) continued on previously started therapy. Patients initiated on ChEI therapy frequently had infection (20 of 42) and were commonly initiated on antipsychotics (14 of 42) and benzodiazepines (13 of 42). Patients were hospitalized for a median of 2 days (interquartile range, 1-4) before initiation of ChEI and were exposed to therapy for a median of 3 days (interquartile range, 2-6). Of the 41 patients discharged from the hospital, 90% (n = 37) had orders to continue the ChEI postdischarge.

CONCLUSIONS

Despite a lack of evidence to support the practice, 9% of patients who received ChEI therapy were initiated during the inpatient setting. These patients were not routinely screened for delirium and frequently received treatments associated with delirium.

Pediatric delirium: monitoring and management in the pediatric intensive care unit

This review article updates the pediatric medical community on the current literature regarding diagnosis and treatment of delirium in critically ill children. This information will be of value to pediatricians, intensivists, and anesthesiologists in developing delirium monitoring and management protocols in their pediatric critical care units.