Delirium and long-term cognitive impairment

Postoperative Delirium and Postoperative Cognitive Dysfunction: Overlap and Divergence

BACKGROUND

Postoperative delirium and postoperative cognitive dysfunction share risk factors and may co-occur, but their relationship is not well established. The primary goals of this study were to describe the prevalence of postoperative cognitive dysfunction and to investigate its association with in-hospital delirium. The authors hypothesized that delirium would be a significant risk factor for postoperative cognitive dysfunction during follow-up.

METHODS

This study used data from an observational study of cognitive outcomes after major noncardiac surgery, the Successful Aging after Elective Surgery study. Postoperative delirium was evaluated each hospital day with confusion assessment method-based interviews supplemented by chart reviews. Postoperative cognitive dysfunction was determined using methods adapted from the International Study of Postoperative Cognitive Dysfunction. Associations between delirium and postoperative cognitive dysfunction were examined at 1, 2, and 6 months.

RESULTS

One hundred thirty-four of 560 participants (24%) developed delirium during hospitalization. Slightly fewer than half (47%, 256 of 548) met the International Study of Postoperative Cognitive Dysfunction-defined threshold for postoperative cognitive dysfunction at 1 month, but this proportion decreased at 2 months (23%, 123 of 536) and 6 months (16%, 85 of 528). At each follow-up, the level of agreement between delirium and postoperative cognitive dysfunction was poor (kappa less than .08) and correlations were small (r less than .16). The relative risk of postoperative cognitive dysfunction was significantly elevated for patients with a history of postoperative delirium at 1 month (relative risk = 1.34; 95% CI, 1.07-1.67), but not 2 months (relative risk = 1.08; 95% CI, 0.72-1.64), or 6 months (relative risk = 1.21; 95% CI, 0.71-2.09).

CONCLUSIONS

Delirium significantly increased the risk of postoperative cognitive dysfunction in the first postoperative month; this relationship did not hold in longer-term follow-up. At each evaluation, postoperative cognitive dysfunction was more common among patients without delirium. Postoperative delirium and postoperative cognitive dysfunction may be distinct manifestations of perioperative neurocognitive deficits.

Delirium detection in older acute medical inpatients: a multicentre prospective comparative diagnostic test accuracy study of the 4AT and the confusion assessment method

BACKGROUND

Delirium affects > 15% of hospitalised patients but is grossly underdetected, contributing to poor care. The 4 'A's Test (4AT, www.the4AT.com ) is a short delirium assessment tool designed for routine use without special training. The primary objective was to assess the accuracy of the 4AT for delirium detection. The secondary objective was to compare the 4AT with another commonly used delirium assessment tool, the Confusion Assessment Method (CAM).

METHODS

This was a prospective diagnostic test accuracy study set in emergency departments or acute medical wards involving acute medical patients aged ≥ 70. All those without acutely life-threatening illness or coma were eligible. Patients underwent (1) reference standard delirium assessment based on DSM-IV criteria and (2) were randomised to either the index test (4AT, scores 0-12; prespecified score of > 3 considered positive) or the comparator (CAM; scored positive or negative), in a random order, using computer-generated pseudo-random numbers, stratified by study site, with block allocation. Reference standard and 4AT or CAM assessments were performed by pairs of independent raters blinded to the results of the other assessment.

RESULTS

Eight hundred forty-three individuals were randomised: 21 withdrew, 3 lost contact, 32 indeterminate diagnosis, 2 missing outcome, and 785 were included in the analysis. Mean age was 81.4 (SD 6.4) years. 12.1% (95/785) had delirium by reference standard assessment, 14.3% (56/392) by 4AT, and 4.7% (18/384) by CAM. The 4AT had an area under the receiver operating characteristic curve of 0.90 (95% CI 0.84-0.96). The 4AT had a sensitivity of 76% (95% CI 61-87%) and a specificity of 94% (95% CI 92-97%). The CAM had a sensitivity of 40% (95% CI 26-57%) and a specificity of 100% (95% CI 98-100%).

CONCLUSIONS

The 4AT is a short, pragmatic tool which can help improving detection rates of delirium in routine clinical care.

TRIAL REGISTRATION

International standard randomised controlled trial number (ISRCTN) 53388093 . Date applied 30/05/2014; date assigned 02/06/2014.

Prevention of postoperative delirium in elderly patients planned for elective surgery: systematic review and meta-analysis

Introduction: Vulnerable or “frail” patients are susceptible to the development of delirium when exposed to triggers such as surgical procedures. Once delirium occurs, interventions have little effect on severity or duration, emphasizing the importance of primary prevention. This review provides an overview of interventions to prevent postoperative delirium in elderly patients undergoing elective surgery.

Methods: A literature search was conducted in March 2018. Randomized controlled trials (RCTs) and before-and-after studies on interventions with potential effects on postoperative delirium in elderly surgical patients were included. Acute admission, planned ICU admission, and cardiac patients were excluded. Full texts were reviewed, and quality was assessed by two independent reviewers. Primary outcome was the incidence of delirium. Secondary outcomes were severity and duration of delirium. Pooled risk ratios (RRs) were calculated for incidences of delirium where similar intervention techniques were used.

Results: Thirty-one RCTs and four before-and-after studies were included for analysis. In 19 studies, intervention decreased the incidences of postoperative delirium. Severity was reduced in three out of nine studies which reported severity of delirium. Duration was reduced in three out of six studies. Pooled analysis showed a significant reduction in delirium incidence for dexmedetomidine treatment, and bispectral index (BIS)-guided anaesthesia. Based on sensitivity analyses, by leaving out studies with a high risk of bias, multicomponent interventions and antipsychotics can also significantly reduce the incidence of delirium.

Conclusion: Multicomponent interventions, the use of antipsychotics, BIS-guidance, and dexmedetomidine treatment can successfully reduce the incidence of postoperative delirium in elderly patients undergoing elective, non-cardiac surgery. However, present studies are heterogeneous, and high-quality studies are scarce. Future studies should add these preventive methods to already existing multimodal and multidisciplinary interventions to tackle as many precipitating factors as possible, starting in the pre-admission period.

Impact of an educational workshop upon psychiatrists' attitudes towards delirium care

OBJECTIVES

Improving knowledge about delirium care is a key target for health care. We describe the implementation of a four-part workshop focusing upon key aspects of delirium care.

METHODS

Attitudes towards and understanding of delirium diagnosis and management amongst psychiatrists were surveyed before and immediately after an educational workshop.

RESULTS

There were 62 participants. Pre-workshop, delirium was rated highly relevant to psychiatry. Overall level of confidence in diagnosis was modest, with the behavioural and psychological symptoms of dementia considered the most challenging differential diagnosis. Only nine participants (15%) correctly identified DSM-5 delirium criteria. Preferred assessment of attention varied with six different approaches endorsed. Confidence was higher for managing hyperactive compared with hypoactive delirium (p<0.001). Pharmacotherapy was more frequently endorsed for hyperactive compared with hypoactive presentations, with haloperidol the most popular agent (p<0.001). A total of 41 (66%) participants completed post-workshop assessments. Post-workshop, there were significant increases to the perceived relevance of delirium (p = 0.003), confidence in overall diagnosis (p<0.001) accuracy of awareness of DSM-5 criteria (p<0.001), and confidence in treating different presentations (p<0.001). The Months Backward Test was the preferred bedside test of attention (38/40 respondents).

CONCLUSIONS

This interactive educational intervention impacted positively upon knowledge and attitudes amongst psychiatrists towards key aspects of delirium care. Further investigation can examine the impact upon longer term knowledge and behaviour.

Trajectory of severity of postoperative delirium symptoms and its prospective association with cognitive function in patients with gastric cancer: results from a prospective observational study

PURPOSE

Delirium is a common neurocognitive complication in cancer. Despite this, the studies examining the trajectory of the severity of delirium symptoms and its impact on health outcome in gastric cancer is rather limited. This study examined the trajectory of delirium symptom severity (DSS) following resection surgery for gastric cancer and its prospective association with cognitive function.

METHODS

A three-wave prospective observational study was conducted with 242 gastric cancer patients admitted for resection surgery at a teaching hospital in South Korea from May 2016 to November 2017. DSS was assessed by the clinical staff before and 1, 2, 3, and 7 days after surgery using the Delirium Rating Scale-Revised-98. A survey including the Functional Assessment of Cancer Therapy-Cognitive Scale (FACT-Cog) and Mini-Mental State Examination (MMSE) was administered before surgery (T0), 7 days after (T1), and 3 to 6 months after surgery (T2).

RESULTS

Out of 242 participants, 48.8% (118) completed the survey at all three time points, 43.4% (105) did so for two time points, and 7.9% (19) for one time point. No cases of full delirium were observed over four postoperative time points. Latent growth curve modeling analyses indicated that DSS declined over 3 days after surgery. Age and anesthesia time were positively associated with the initial level of DSS. A medication history for memory complaints was related to a slower recovery from delirium symptoms. While the use of propofol as an anesthetic agent was associated with lower initial DSS, it predicted a slower recovery from DSS. A higher initial DSS predicted a lower T1 MMSE score.

CONCLUSIONS

Severity of postoperative delirium symptoms predicts a short-term and objective cognitive function post-surgery. Monitoring and timely treatment of postoperative delirium symptoms is needed to diminish cognitive consequences in gastric cancer patients.

Sedation, Delirium, and Cognitive Function After Critical Illness

Delirium has been consistently identified as a risk factor for critical illness brain injury, but ICU patients are exposed to a multitude of risk factors for delirium and it remains unclear which of these risk factors should be targeted to improve long-term cognitive outcomes. Because exposure to sedating medications-which are frequently used to treat unwanted yet common symptoms during critical illness-is a risk factor for delirium that is directly controlled by clinicians, the relationship between sedation, delirium, and long-term cognition is of great interest to clinicians, researchers, and patients. This review describes theoretic relationships between sedation, delirium, and long-term cognition and reviews the evidence supporting these theoretic relationships.

Acute transient cognitive dysfunction and acute brain injury induced by systemic inflammation occur by dissociable IL-1-dependent mechanisms

Systemic inflammation can impair cognition with relevance to dementia, delirium and post-operative cognitive dysfunction. Episodes of delirium also contribute to rates of long-term cognitive decline, implying that these acute events induce injury. Whether systemic inflammation-induced acute dysfunction and acute brain injury occur by overlapping or discrete mechanisms remains unexplored. Here we show that systemic inflammation, induced by bacterial LPS, produces both working-memory deficits and acute brain injury in the degenerating brain and that these occur by dissociable IL-1-dependent processes. In normal C57BL/6 mice, LPS (100 µg/kg) did not affect working memory but impaired long-term memory consolidation. However prior hippocampal synaptic loss left mice selectively vulnerable to LPS-induced working memory deficits. Systemically administered IL-1 receptor antagonist (IL-1RA) was protective against, and systemic IL-1β replicated, these working memory deficits. Dexamethasone abolished systemic cytokine synthesis and was protective against working memory deficits, without blocking brain IL-1β synthesis. Direct application of IL-1β to ex vivo hippocampal slices induced non-synaptic depolarisation and irreversible loss of membrane potential in CA1 neurons from diseased animals and systemic LPS increased apoptosis in the degenerating brain, in an IL-1RI-dependent fashion. The data suggest that LPS induces working memory dysfunction via circulating IL-1β but direct hippocampal action of IL-1β causes neuronal dysfunction and may drive neuronal death. The data suggest that acute systemic inflammation produces both reversible cognitive deficits, resembling delirium, and acute brain injury contributing to long-term cognitive impairment but that these events are mechanistically dissociable. These data have significant implications for management of cognitive dysfunction during acute illness.

A systematic review of neuroimaging in delirium: predictors, correlates and consequences

OBJECTIVE

Neuroimaging advances our understanding of delirium pathophysiology and its consequences. A previous systematic review identified 12 studies (total participants N = 764, delirium cases N = 194; years 1989-2007) and found associations with white matter hyperintensities (WMH) and cerebral atrophy. Our objectives were to perform an updated systematic review of neuroimaging studies in delirium published since January 2006 and summarise the available literature on predictors, correlates or outcomes.

METHODS

Studies were identified by keyword and MeSH-based electronic searches of EMBASE, MEDLINE and PsycINFO combining terms for neuroimaging, brain structure and delirium. We included neuroimaging studies of delirium in adults using validated delirium assessment methods.

RESULTS

Thirty-two studies (total N = 3187, delirium N = 1086) met the inclusion criteria. Imaging included magnetic resonance imaging (MRI; N = 9), computed tomography (N = 4), diffusion tensor imaging (N = 3), transcranial Doppler (N = 5), near infrared spectroscopy (N = 5), functional-MRI (N = 2), single photon emission computed tomography (N = 1), proton MRI spectroscopy (N = 1), arterial spin-labelling MRI (N = 1) and 2-¹³ fluoro-2-deoxyglucose positron emission tomography (N = 1). Despite heterogeneity in study design, delirium was associated with WMH, lower brain volume, atrophy, dysconnectivity, impaired cerebral autoregulation, reduced blood flow and cerebral oxygenation and glucose hypometabolism. There was evidence of long-term brain changes following intensive care unit delirium.

CONCLUSIONS

Neuroimaging is now used more widely in delirium research due to advances in technology. However, imaging delirious patients presents challenges leading to methodological limitations and restricted generalisability. The findings that atrophy and WMH burden predict delirium replicates findings from the original review, while advanced techniques have identified other substrates and mechanisms that warrant further investigation.

Defining delirium in idiopathic Parkinson's disease: A systematic review

BACKGROUND

Parkinson's disease patients may be at increased risk of delirium and developing adverse outcomes, such as cognitive decline and increased mortality. Delirium is an acute state of confusion that has overlapping symptoms with Parkinson's dementia, making it difficult to identify. This study aimed to determine the diagnostic criteria, prevalence, management strategies and outcomes of delirium in Parkinson's through a systematic review of the literature.

METHODS

Seven databases were used to identify all articles published before February 2017 comprising two key terms: "Parkinson's Disease" and "delirium". Data were extracted from studies meeting predefined inclusion criteria.

RESULTS

Twenty articles were identified. Delirium prevalence in Parkinson's ranged from 0.3 to 60% depending on setting; a diagnosis of Parkinson's was associated with an increased risk of developing delirium. Delirium was identified/diagnosed using seven different criteria. Delirium may be associated with an increased length of hospital stay and worsening motor symptoms. We did not identify any studies examining the management of delirium in Parkinson's.

DISCUSSION

This review highlights the paucity of well-designed, appropriately powered studies investigating delirium in Parkinson's. The results suggest that delirium is a significant issue in people with Parkinson's and that having delirium may be a risk factor for adverse outcomes, particularly in inpatient settings. Further prospective research is needed to accurately determine the prevalence of delirium in Parkinson's, its management strategies and outcomes, and to evaluate diagnostic criteria to differentiate between the overlapping symptoms of Parkinson's and delirium.

Diagnostic test accuracy of a novel smartphone application for the assessment of attention deficits in delirium in older hospitalised patients: a prospective cohort study protocol

Background

Delirium is a common and serious clinical syndrome which is often missed in routine clinical care. The core cognitive feature is inattention. We developed a novel bedside neuropsychological test for assessing inattention in delirium implemented on a smartphone platform (DelApp). We aim to evaluate the diagnostic performance of the DelApp in a representative cohort of older hospitalised patients.

Methods

This is a prospective study of older non-scheduled hospitalised patients (target n = 500, age ≥ 65), recruited from elderly care and acute orthopaedic wards. Exclusion criteria are: non-English speakers; severe vision or hearing impairment; photosensitive epilepsy.

A structured reference standard delirium assessment based on DSM-5 criteria will be used, which includes a cognitive test battery administered by a trained assessor (Orientation-Memory-Concentration Test, Abbreviated Mental Test-10, Delirium Rating Severity Scale-Revised-98, digit span, months and days backwards, Vigilance A’ test) and assessment of arousal (Observational Scale of Level of Arousal, Richmond Agitation Sedation Scale). Prior change in cognition will be documented using the Informant Questionnaire on Cognitive Decline in the Elderly. Patients will be categorized as delirium (with/without dementia), possible delirium, dementia, no cognitive impairment, or undetermined.

A separate assessor (blinded to diagnosis and assessments) will administer the DelApp index test within 3 h of the reference standard assessment. The DelApp comprises assessment of arousal (score 0-4) and sustained attention (score 0-6), yielding a total score between 0 and 10 (higher score = better performance). Outcomes (length of stay, mortality and discharge location) will be collected at 12 weeks.

We will evaluate a priori cutpoints derived from a previous case-control study. Measures of the accuracy of DelApp will include sensitivity, specificity, positive and negative predictive values, and area under the ROC curve. We plan repeat assessments on up to 4 occasions in a purposive subsample of 30 patients (15 delirium, 15 no delirium) to examine changes over time.

Discussion

This study evaluates the diagnostic test accuracy of a novel smartphone test for delirium in a representative cohort of older hospitalised patients, including those with dementia. DelApp has the potential to be a convenient, objective method of improving delirium assessment for older people in acute care.

Trial registration

Clinical trials.gov, NCT02590796. Registered on 29 Oct 2015. Protocol version 5, dated 25 July 2016.

Electronic supplementary material

The online version of this article (10.1186/s12877-018-0901-5) contains supplementary material, which is available to authorized users.

Emotional and Psychological Needs of People with Diabetes

Diabetes is a chronic metabolic disorder that impacts physical, social and mental including psychological well-being of people living with it. Additionally, psychosocial problems that are most common in diabetes patients often result in serious negative impact on patient's well-being and social life, if left un-addressed. Addressing such psychosocial aspects including cognitive, emotional, behavioral and social factors in the treatment interventions would help overcome the psychological barriers, associated with adherence and self-care for diabetes; the latter being the ultimate goal of management of patients with diabetes. While ample literature on self-management and psychological interventions for diabetes is available, there is limited information on the impact of psychological response and unmanaged emotional distresses on overall health. The current review therefore examines the emotional, psychological needs of the patients with diabetes and emphasizes the role of diabetologist, mental health professionals including clinical psychologists to mitigate the problems faced by these patients. Search was performed using a combination of keywords that cover all relevant terminology for diabetes and associated emotional distress. The psychological reactions experienced by the patient upon diagnosis of diabetes have been reviewed in this article with a focus on typical emotional distress at different levels. Identifying and supporting patients with psychosocial problems early in the course of diabetes may promote psychosocial well-being and improve their ability to adjust or take adequate responsibility in diabetes self-management - the utopian state dreamt of by all diabetologists !.

Cognitive Decline after Delirium in Patients Undergoing Cardiac Surgery

WHAT WE ALREADY KNOW ABOUT THIS TOPIC

Cardiac surgery is associated with cognitive decline and postoperative delirium. The relationship between postoperative delirium and cognitive decline after cardiac surgery is unclear

WHAT THIS ARTICLE TELLS US THAT IS NEW

The development of postoperative delirium is associated with a greater degree of cognitive decline 1 month after cardiac surgery. The development of postoperative delirium is not a predictor of cognitive decline 1 yr after cardiac surgery.

BACKGROUND

Delirium is common after cardiac surgery and has been associated with morbidity, mortality, and cognitive decline. However, there are conflicting reports on the magnitude, trajectory, and domains of cognitive change that might be affected. The authors hypothesized that patients with delirium would experience greater cognitive decline at 1 month and 1 yr after cardiac surgery compared to those without delirium.

METHODS

Patients who underwent coronary artery bypass and/or valve surgery with cardiopulmonary bypass were eligible for this cohort study. Delirium was assessed with the Confusion Assessment Method. A neuropsychologic battery was administered before surgery, at 1 month, and at 1 yr later. Linear regression was used to examine the association between delirium and change in composite cognitive Z score from baseline to 1 month (primary outcome). Secondary outcomes were domain-specific changes at 1 month and composite and domain-specific changes at 1 yr.

RESULTS

The incidence of delirium in 142 patients was 53.5%. Patients with delirium had greater decline in composite cognitive Z score at 1 month (greater decline by -0.29; 95% CI, -0.54 to -0.05; P = 0.020) and in the domains of visuoconstruction and processing speed. From baseline to 1 yr, there was no difference between delirious and nondelirious patients with respect to change in composite cognitive Z score, although greater decline in processing speed persisted among the delirious patients.

CONCLUSIONS

Patients who developed delirium had greater decline in a composite measure of cognition and in visuoconstruction and processing speed domains at 1 month. The differences in cognitive change by delirium were not significant at 1 yr, with the exception of processing speed.

Refining Delirium: A Transtheoretical Model of Delirium Disorder with Preliminary Neurophysiologic Subtypes

The development of delirium indicates neurophysiologic disruption and predicts unfavorable outcomes. This relationship between delirium and its outcomes has inspired a generation of studies aimed at identifying, predicting, and preventing both delirium and its associated sequelae. Despite this, evidence on delirium prevention and management remains limited. No medication is approved for the prevention or treatment of delirium or for its associated psychiatric symptoms. This unmet need for effective delirium treatment calls for a refined approach. First, we explain why a one-size-fits-all approach based on a unitary biological model of delirium has contributed to variance in delirium studies and prevents further advance in the field. Next, in parallel with the shift from dementia to "major neurocognitive disorder," we propose a transtheoretical model of "delirium disorder" composed of interactive elements-precipitant, neurophysiology, delirium phenotype, and associated psychiatric symptoms. We explore how these relate both to the biopsychosocial factors that promote healthy cognition ("procognitive factors") and to consequent neuropathologic sequelae. Finally, we outline a preliminary delirium typology of specific neurophysiologic disturbances. Our model of delirium disorder offers several avenues for novel insights and clinical advance: it univocally differentiates delirium disorder from the phenotype of delirium, highlights delirium neurophysiology as a treatment target, separates the core features of delirium from associated psychiatric symptoms, suggests how procognitive factors influence the core elements of delirium disorder, and makes intuitive predictions about how delirium disorder leads to neuropathologic sequelae and cognitive impairment. Ultimately, this model opens several avenues for modern neuroscience to unravel this disease of antiquity.

A hospital-wide evaluation of delirium prevalence and outcomes in acute care patients - a cohort study

Background

Delirium is a well-known complication in cardiac surgery and intensive care unit (ICU) patients. However, in many other settings its prevalence and clinical consequences are understudied. The aims of this study were: (1) To assess delirium prevalence in a large, diverse cohort of acute care patients classified as either at risk or not at risk for delirium; (2) To compare these two groups according to defined indicators; and (3) To compare delirious with non-delirious patients regarding hospital mortality, ICU and hospital length of stay, nursing hours and cost per case.

Methods

This cohort study was performed in a Swiss university hospital following implementation of a delirium management guideline. After excluding patients aged < 18 years or with a length of stay (LOS) < 1 day, 29′278 patients hospitalized in the study hospital in 2014 were included.

Delirium period prevalence was calculated based on a Delirium Observation Scale (DOS) score ≥ 3 and / or Intensive Care Delirium Screening Checklist (ICDSC) scores ≥4.

Results

Of 10′906 patients admitted, DOS / ICDSC scores indicated delirium in 28.4%. Delirium was most prevalent (36.2–40.5%) in cardiac surgery, neurosurgery, trauma, radiotherapy and neurology patients. It was also common in geriatrics, internal medicine, visceral surgery, reconstructive plastic surgery and cranio-maxillo-facial surgery patients (prevalence 21.6–28.6%). In the unadjusted and adjusted models, delirious patients had a significantly higher risk of inpatient mortality, stayed significantly longer in the ICU and hospital, needed significantly more nursing hours and generated significantly higher costs per case. For the seven most common ICD-10 diagnoses, each diagnostic group’s delirious patients had worse outcomes compared to those with no delirium.

Conclusions

The results indicate a high number of patients at risk for delirium, with high delirium prevalence across all patient groups. Delirious patients showed significantly worse clinical outcomes and generated higher costs. Subgroup analyses highlighted striking variations in delirium period-prevalence across patient groups. Due to the high prevalence of delirium in patients treated in care centers for radiotherapy, visceral surgery, reconstructive plastic surgery, cranio-maxillofacial surgery and oral surgery, it is recommended to expand the current focus of delirium management to these patient groups.

Electronic supplementary material

The online version of this article (10.1186/s12913-018-3345-x) contains supplementary material, which is available to authorized users.

Sevoflurane exerts brain-protective effects against sepsis-associated encephalopathy and memory impairment through caspase 3/9 and Bax/Bcl signaling pathway in a rat model of sepsis

Objective We compared the effects of sevoflurane and isoflurane on systemic inflammation, sepsis-associated encephalopathy, and memory impairment in a rat sepsis model of cecal ligation and puncture (CLP)-induced polymicrobial peritonitis. Methods Twenty-four rats were assigned to sham, CLP, CLP + sevoflurane, and CLP + isoflurane groups. At 72 hours after CLP, the rats underwent behavior tests. Serum cytokines were evaluated. Brain tissue samples were collected for determination of glutathione peroxidase (GPX), superoxide dismutase (SOD), and catalase; the wet/dry weight ratio; myeloperoxidase (MPO) and malondialdehyde (MDA); apoptotic gene release; and histologic examinations. Results The MPO level, wet/dry weight ratio, and histopathology scores were lower and the Bcl2a1 and Bcl2l2 expressions were upregulated in both the CLP + sevoflurane and CLP + isoflurane groups compared with the CLP group. The interleukin-6, interleukin-1β, MDA, and caspase 3, 8, and 9 levels were lower; the GPX, SOD, Bax, Bcl2, and Bclx levels were higher; and non-associative and aversive memory were improved in the CLP + sevoflurane group compared with the CLP + isoflurane group. Conclusion Sevoflurane decreased apoptosis and oxidative injury and improved memory in this experimental rat model of CLP. Sevoflurane sedation may protect against brain injury and memory impairment in septic patients.

The Person, Interactions and Environment Programme to improve care of people with dementia in hospital: a multisite study

Background

Improving the care of people with dementia on acute hospital wards is a policy priority. Person-centred care is a marker of care quality; delivering such care is a goal of service improvement.

Objectives

The Person, Interactions and Environment (PIE) Programme comprises an observation tool and a systematic approach to implement and embed a person-centred approach in routine care for hospitalised patients with dementia. The study aims were to evaluate PIE as a method to improve the care of older people with dementia on acute hospital wards, and develop insight into what person-centred care might look like in practice in this setting.

Methods

We performed a longitudinal comparative case study design in 10 purposively selected wards in five trusts in three English regions, alongside an embedded process evaluation. Data were collected from multiple sources: staff, patients, relatives, organisational aggregate information and documents. Mixed methods were employed: ethnographic observation; interviews and questionnaires; patient case studies (patient observation and conversations ‘in the moment’, interviews with relatives and case records); and patient and ward aggregate data. Data were synthesised to create individual case studies of PIE implementation and outcomes in context of ward structure, organisation, patient profile and process of care delivery. A cross-case comparison facilitated a descriptive and explanatory account of PIE implementation in context, the pattern of variation, what shaped it and the consequences flowing from it. Quantitative data were analysed using simple descriptive statistics. A qualitative data analysis employed grounded theory methods.

Results

The study furthered the understanding of the dimensions of care quality for older people with dementia on acute hospital wards and the environmental, organisational and cultural factors that shaped delivery. Only two wards fully implemented PIE, sustaining and embedding change over 18 months. The remaining wards either did not install PIE (‘non-implementers’) or were ‘partial implementers’. The interaction between micro-level contextual factors [aspects of leadership (drivers, facilitators, team, networks), fit with strategic initiatives and salience with valued goals] and meso- and macro-level organisational factors were the main barriers to PIE adoption. Evidence suggests that the programme, where implemented, directly affected improvements in ward practice, with a positive impact on the experiences of patients and caregivers, although the heterogeneity of need and severity of impairment meant that some of the more visible changes did not affect everyone equally.

Limitations

Although PIE has the potential to improve the care of people with dementia when implemented, findings are indicative only: data on clinical outcomes were not systematically collected, and PIE was not adopted on most study wards.

Research implications

Further research is required to identify more precisely the skill mix and resources necessary to provide person-focused care to hospitalised people with dementia, across the spectrum of need, including those with moderate and severe impairment. Implementing innovations to change practices in complex organisations requires a more in-depth understanding of the contextual factors that have an impact on the capacity of organisations to absorb and embed new practices.

Funding

The National Institute for Health Research Health Services and Delivery Research programme.

Development of dementia in patients with femoral neck fracture who experience postoperative delirium-A three-year follow-up study

OBJECTIVES

It remains unclear to what extent postoperative delirium (POD) affects the incidence of dementia in hip fracture patients, and the methods used to detect delirium and dementia require validation. The aim of this study was to investigate the development of dementia within 3 years of femoral neck fracture repair surgery, with a focus on POD as a potential predictive factor.

METHODS

Patients were assessed for cognition, delirium, depression, psychological well-being, and nutritional status during their hospitalization as well as 4, 12, and 36 months after the operation. Logistic regression models were used to analyse factors associated with POD and factors associated with the development of dementia.

RESULTS

The study sample consisted of 135 patients without a history of dementia, of whom 20 (14.8%) were delirious preoperatively and 75 (55.5%) postoperatively. Three years after their operations, 43/135 patients (31.8%) were diagnosed with dementia. A greater portion of patients diagnosed with dementia (39/43, 90.6%) than patients with no dementia (36/92, 39.1%) were included among the 75 patients who had experienced POD (P < 0.001). In a logistic regression model, after adjustment for covariates (age, sex, diabetes, delirium pre-and postoperatively, hyperactive delirium, days with delirium, urinary tract infection, and Mini Nutritional Assessment score), POD emerged an independent predictor for the development of new dementia (odds ratio, 15.6; 95% confidence interval, 2.6-91.6) within 3 years after the operation.

CONCLUSION

Geriatric hip fracture patients who exhibit POD should be monitored closely for the development of dementia.

Genome-wide association identifies a novel locus for delirium risk

We aimed to identify common genetic variations associated with delirium through genome-wide association testing in a hospital biobank. We applied a published electronic health record-based definition of delirium to identify cases of delirium, and control individuals with no history of delirium, from a biobank spanning 2 Boston academic medical centers. Among 6035 individuals of northern European ancestry, including 421 with a history of delirium, we used logistic regression to examine genome-wide association. We identified one locus spanning multiple genes, including 3 interleukin-related genes, associated with p = 1.41e-8, and 5 other independent loci with p < 5e-7. Our results do not support previously reported candidate gene associations in delirium. Identifying common-variant associations with delirium may provide insight into the mechanisms responsible for this complex and multifactorial outcome. Using standardized claims-based phenotypes in biobanks should allow the larger scale investigations required to confirm novel loci such as the one we identify.

Protocol for validation of the 4AT, a rapid screening tool for delirium: a multicentre prospective diagnostic test accuracy study

INTRODUCTION

Delirium is a severe neuropsychiatric syndrome of rapid onset, commonly precipitated by acute illness. It is common in older people in the emergency department (ED) and acute hospital, but greatly under-recognised in these and other settings. Delirium and other forms of cognitive impairment, particularly dementia, commonly coexist. There is a need for a rapid delirium screening tool that can be administered by a range of professional-level healthcare staff to patients with sensory or functional impairments in a busy clinical environment, which also incorporates general cognitive assessment. We developed the 4 'A's Test (4AT) for this purpose. This study's primary objective is to validate the 4AT against a reference standard. Secondary objectives include (1) comparing the 4AT with another widely used test (the Confusion Assessment Method (CAM)); (2) determining if the 4AT is sensitive to general cognitive impairment; (3) assessing if 4AT scores predict outcomes, including (4) a health economic analysis.

METHODS AND ANALYSIS

900 patients aged 70 or over in EDs or acute general medical wards will be recruited in three sites (Edinburgh, Bradford and Sheffield) over 18 months. Each patient will undergo a reference standard delirium assessment and will be randomised to assessment with either the 4AT or the CAM. At 12 weeks, outcomes (length of stay, institutionalisation and mortality) and resource utilisation will be collected by a questionnaire and via the electronic patient record.

ETHICS AND DISSEMINATION

Ethical approval was granted in Scotland and England. The study involves administering tests commonly used in clinical practice. The main ethical issues are the essential recruitment of people without capacity. Dissemination is planned via publication in high impact journals, presentation at conferences, social media and the website www.the4AT.com.

TRIAL REGISTRATION NUMBER

ISRCTN53388093; Pre-results.

Delirium in the Pediatric Cardiac Extracorporeal Membrane Oxygenation Patient Population: A Case Series

OBJECTIVE

To determine the prevalence of delirium in children who require extracorporeal membrane oxygenation.

DESIGN

Prospective observational longitudinal cohort study.

SETTING

Urban academic cardiothoracic ICU.

PATIENTS

All consecutive admissions to the cardiothoracic ICU who required venoarterial extracorporeal membrane oxygenation support.

INTERVENTIONS

Daily delirium screening with the Cornell Assessment for Pediatric Delirium.

MEASUREMENTS AND MAIN RESULTS

Eight children required extracorporeal membrane oxygenation during the study period, with a median extracorporeal membrane oxygenation duration of 202 hours (interquartile range, 99-302). All eight children developed delirium during their cardiothoracic ICU stay. Seventy-two days on extracorporeal membrane oxygenation were included in the analysis. A majority of patient days on extracorporeal membrane oxygenation were spent in coma (65%). Delirium was diagnosed during 21% of extracorporeal membrane oxygenation days. Only 13% of extracorporeal membrane oxygenation days were categorized as delirium free and coma free. Delirium screening was successfully completed on 70/72 days on extracorporeal membrane oxygenation (97%).

CONCLUSIONS

In this cohort, delirium occurred in all children who required venoarterial extracorporeal membrane oxygenation. It is likely that this patient population has an extremely high risk for delirium and will benefit from routine screening in order to detect and treat delirium sooner. This has potential to improve both short- and long-term outcomes.

Delirium in the Critically Ill Child: Assessment and Sequelae

Delirium is a common and serious neuropsychiatric complication in critically ill patients of all ages. In the context of critical illness, delirium may emerge as a result of a cascade of underlying pathophysiologic mechanisms and signals organ failure of the brain. Awareness of the clinical importance of delirium in adults is growing as emerging research demonstrates that delirium represents a serious medical problem with significant sequelae. However, our understanding of delirium in children lags significantly behind the adult literature. In particular, our knowledge of how to assess delirium is complicated by challenges in recognizing symptoms of delirium in pediatric patients especially in critical and intensive care settings, and our understanding of its impact on acute and long-term functioning remains in its infancy. This paper focuses on (a) the challenges associated with assessing delirium in critically ill children, (b) the current literature on the outcomes of delirium including morbidity following discharge from PICU, and care-giver well-being, and (c) the importance of assessment in determining impact of delirium on outcome. Current evidence suggests that delirium is a diagnostic challenge for clinicians and may play a detrimental role in a child's recovery after discharge from the pediatric intensive care unit (PICU). Recommendations are proposed for how our knowledge and assessment of delirium in children could be improved.

Psychiatric symptomatology after delirium: a systematic review

Delirium is an acute and usually transient severe neuropsychiatric syndrome associated with significant long-term physical morbidity. However, its chronic psychiatric sequelae remain poorly characterized. To investigate the prevalence of psychiatric symptoms, namely anxiety, depressive, and post-traumatic stress disorder (PTSD) symptoms after delirium, a systematic literature search of MEDLINE, EMBASE and PsycINFO databases was performed independently by two authors in March 2016. Bibliographies were hand-searched, and a forward- and backward-citation search using Web of Science was performed for all included studies. Of 6411 titles, we included eight prospective cohort studies, including 370 patients with delirium and 1073 without delirium. Studies were heterogeneous and mostly included older people from a range of clinical groups. Consideration of confounders was variable. The prevalence of depressive symptoms was almost three times higher in patients with delirium than in patients without delirium (22.2% vs 8.0%, risk ratio = 2.79; 95% confidence interval = 1.36-5.73). There was no statistically significant difference between the prevalence of anxiety symptoms between patients with and without delirium. The prevalence of PTSD symptoms after delirium was inconclusive: only one study investigated this and no association between PTSD symptoms after delirium was reported. There is limited published evidence of the prevalence of psychiatric symptoms after non-ICU delirium and the strongest evidence is for depressive symptoms. Further longitudinal studies are warranted to investigate the prevalence of anxiety and PTSD symptoms.

Protocol for the Delirium and Cognitive Impact in Dementia (DECIDE) study: A nested prospective longitudinal cohort study

BACKGROUND

Delirium is common, affecting at least 20% of older hospital inpatients. It is widely accepted that delirium is associated with dementia but the degree of causation within this relationship is unclear. Previous studies have been limited by incomplete ascertainment of baseline cognition or a lack of prospective delirium assessments. There is an urgent need for an improved understanding of the relationship between delirium and dementia given that delirium prevention may plausibly impact upon dementia prevention. A well-designed, observational study could also answer fundamental questions of major importance to patients and their families regarding outcomes after delirium. The Delirium and Cognitive Impact in Dementia (DECIDE) study aims to explore the association between delirium and cognitive function over time in older participants. In an existing population based cohort aged 65 years and older, the effect on cognition of an episode of delirium will be measured, independent of baseline cognition and illness severity. The predictive value of clinical parameters including delirium severity, baseline cognition and delirium subtype on cognitive outcomes following an episode of delirium will also be explored.

METHODS

Over a 12 month period, surviving participants from the Cognitive Function and Ageing Study II-Newcastle will be screened for delirium on admission to hospital. At the point of presentation, baseline characteristics along with a number of disease relevant clinical parameters will be recorded. The progression/resolution of delirium will be monitored. In those with and without delirium, cognitive decline and dementia will be assessed at one year follow-up. We will evaluate the effect of delirium on cognitive function over time along with the predictive value of clinical parameters.

DISCUSSION

This study will be the first to prospectively elucidate the size of the effect of delirium upon cognitive decline and incident dementia. The results will be used to inform future dementia prevention trials that focus on delirium intervention.

Delirium in Critically Ill Children: An International Point Prevalence Study

OBJECTIVES

To determine prevalence of delirium in critically ill children and explore associated risk factors.

DESIGN

Multi-institutional point prevalence study.

SETTING

Twenty-five pediatric critical care units in the United States, the Netherlands, New Zealand, Australia, and Saudi Arabia.

PATIENTS

All children admitted to the pediatric critical care units on designated study days (n = 994).

INTERVENTION

Children were screened for delirium using the Cornell Assessment of Pediatric Delirium by the bedside nurse. Demographic and treatment-related variables were collected.

MEASUREMENTS AND MAIN RESULTS

Primary study outcome measure was prevalence of delirium. In 159 children, a final determination of mental status could not be ascertained. Of the 835 remaining subjects, 25% screened positive for delirium, 13% were classified as comatose, and 62% were delirium-free and coma-free. Delirium prevalence rates varied significantly with reason for ICU admission, with highest delirium rates found in children admitted with an infectious or inflammatory disorder. For children who were in the PICU for 6 or more days, delirium prevalence rate was 38%. In a multivariate model, risk factors independently associated with development of delirium included age less than 2 years, mechanical ventilation, benzodiazepines, narcotics, use of physical restraints, and exposure to vasopressors and antiepileptics.

CONCLUSIONS

Delirium is a prevalent complication of critical illness in children, with identifiable risk factors. Further multi-institutional, longitudinal studies are required to investigate effect of delirium on long-term outcomes and possible preventive and treatment measures. Universal delirium screening is practical and can be implemented in pediatric critical care units.

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.

Hospitalized Older Adults With Established Delirium: Recognition, Documentation, and Reporting

Delirium, a life-threatening complication for hospitalized older adults associated with adverse outcomes, is often underrecognized and underreported. The purpose of the current study was to analyze delirium documentation for hospitalized older adults. Charts of 34 patients, aged 71 and older with documented delirium and referral to a Hospital Elder Life Program, were reviewed. With the exception of International Classification of Diseases-9 coding, delirium was only mentioned in 12 (35.3%) charts, although descriptors potentially indicative of delirium were usually recorded. Of these, the most frequently recorded were confusion (94.1%), mental status change (70.6%), and disorientation (61.8%). When nurses charted delirium descriptors, only 5.9% of their notes included physician referral. Physician responses were to order diagnostic tests and medications, usually antipsychotic or benzodiazepine agents. Of 28 patients requiring transfer to another facility after discharge, delirium was mentioned in only one transfer note. Commonly used delirium descriptors can be used for the development of natural language processing tools for clinical decision support. [Journal of Gerontological Nursing, 43(3), 32-40.].

Delirium After Mechanical Ventilation in Intensive Care Units: The Cognitive and Psychosocial Assessment (CAPA) Study Protocol

Background

In the intensive care unit (ICU), critical illness delirium occurs in the context of multiple comorbidities, multi-organ failure, and invasive management techniques, such as mechanical ventilation, sedation, and lack of sleep. Delirium is characterized by an acute confusional state defined by fluctuating mental status, inattention, and either disorganized thinking or an altered level of consciousness. The long-term cognitive and psychosocial function of patients that experience delirium in the ICU is of crucial interest because preliminary data suggest a strong association between ICU-related delirium and long-term cognitive impairment.

Objective

The aim of this study is to explore the relationship between delirium in the ICU and adverse outcomes by following mechanically ventilated patients for one year following their discharge from the ICU and collecting data on their long-term cognition and psychosocial function.

Methods

This study will be conducted by enrolling patients in two tertiary ICUs in Australia. We aim to recruit 200 patients who have been mechanically ventilated for more than 24 hours. Data will be collected at the following three time points: (1) at discharge where they will be administered the Mini-Mental State Examination (MMSE); (2) at 6 months after discharge from the ICU discharge where the Impact of Events Scale Revised (IES-R) and the Telephone Inventory for Cognitive Status (TICS) tests will be administered; and (3) at 12 months after discharge from the ICU where the patients will be administered the TICS and IES-R tests, as well as the Informant Questionnaire for Cognitive Decline in the Elderly (IQCODE). The IQCODE will be administered to their “person responsible” or the significant other of the patient.

Results

Long-term cognition and psychosocial function will be the primary outcome of this study. Mortality will also be investigated as a secondary outcome. Active enrollment will take place until the end of September 2016 and data collection will conclude at the end of September 2017. The analysis and results are expected to be available by March 2018.

Conclusion

Delirium during mechanical ventilation has been linked to longer ICU and hospital stays, higher financial burdens, increased risks of long-term cognitive impairment (ie, dementia), poor functional outcomes and quality of life, and decreased survival. However, delirium during mechanical ventilation in the ICU is not well understood. This study will advance our knowledge of the comprehensive, long-term effects of delirium on cognitive and psychosocial function.

Trial Registration

Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12616001116415; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=371216 (Archived by WebCite at http://www.webcitation.org/ 6nfDkGTcW)

The Association of Serum Levels of Brain-Derived Neurotrophic Factor with the Occurrence of and Recovery from Delirium in Older Medical Inpatients

Limited studies of the association between BDNF levels and delirium have given inconclusive results. This prospective, longitudinal study examined the relationship between BDNF levels and the occurrence of and recovery from delirium. Participants were assessed twice weekly using MoCA, DRS-R98, and APACHE II scales. BDNF levels were estimated using an ELISA method. Delirium was defined with DRS-R98 (score > 16) and recovery from delirium as ≥2 consecutive assessments without delirium prior to discharge. We identified no difference in BDNF levels between those with and without delirium. Excluding those who never developed delirium (n = 140), we examined the association of BDNF levels and other variables with delirium recovery. Of 58 who experienced delirium, 39 remained delirious while 19 recovered. Using Generalized Estimating Equations models we found that BDNF levels (Wald χ² = 7.155; df: 1, p = 0.007) and MoCA (Wald χ² = 4.933; df: 1, p = 0.026) were associated with recovery. No significant association was found for APACHE II, dementia, age, or gender. BDNF levels do not appear to be directly linked to the occurrence of delirium but recovery was less likely in those with continuously lower levels. No previous study has investigated the role of BDNF in delirium recovery and these findings warrant replication in other populations.

Risk factors for incident delirium in an acute general medical setting: a retrospective case-control study

AIMS AND OBJECTIVES

To determine predisposing and precipitating risk factors for incident delirium in medical patients during an acute hospital admission.

BACKGROUND

Incident delirium is the most common complication of hospital admission for older patients. Up to 30% of hospitalised medical patients experience incident delirium. Determining risk factors for delirium is important for identifying patients who are most susceptible to incident delirium.

DESIGN

Retrospective case-control study with two controls per case.

METHODS

An audit tool was used to review medical records of patients admitted to acute medical units for data regarding potential risk factors for delirium. Data were collected between August 2013 and March 2014 at three hospital sites of a healthcare organisation in Melbourne, Australia. Cases were 161 patients admitted to an acute medical ward and diagnosed with incident delirium between 1 January 2012 and 31 December 2013. Controls were 321 patients sampled from the acute medical population admitted within the same time range, stratified for admission location and who did not develop incident delirium during hospitalisation.

RESULTS

Identified using logistic regression modelling, predisposing risk factors for incident delirium were dementia, cognitive impairment, functional impairment, previous delirium and fracture on admission. Precipitating risk factors for incident delirium were use of an indwelling catheter, adding more than three medications during admission and having an abnormal sodium level during admission.

CONCLUSIONS

Multiple risk factors for incident delirium exist; patients with a history of delirium, dementia and cognitive impairment are at greatest risk of developing delirium during hospitalisation.

RELEVANCE TO CLINICAL PRACTICE

Nurses and other healthcare professionals should be aware of patients who have one or more risk factors for incident delirium. Knowledge of risk factors for delirium has the potential to increase the recognition and understanding of patients who are vulnerable to delirium. Early recognition and prevention of delirium can contribute to improved patients safety and reduction in harm.

A systematic review and meta-analysis of the association between the apolipoprotein E genotype and delirium

The role of apolipoprotein E (APOE) in Alzheimer's disease and other dementias has been investigated intensively. However, the relationship between APOE and delirium has only recently been explored in studies that have included relatively small samples. A meta-analysis of the published pooled data is timely to explore the relationship between APOE and delirium and to inform further research in this topic. PubMed, EBSCOhost, Google Scholar, Scopus, all EBM Reviews (OVID) and the Cochrane Database of Systematic Reviews were searched with relevant keywords and from the references of relevant papers. Ten papers were found that examined the relationship between APOE and delirium. Data were extracted from eight of them and pooled for meta-analysis using random effects with R software. Data from 1762 participants, of whom 479 (27.2%) were diagnosed with delirium, showed low heterogeneity (Q=13.11, d.f.=7, P=0.07; I=44.86%). The possession of the APOE ε4 allele has a small (log odds ratio: 0.18, 95% confidence interval: 0.23-0.59), nonsignificant (P=0.38) effect on the presence of delirium. No publication bias was identified. The metapower of the pooled data was low (α=0.05, power=0.65). On analysing the studies to date, it seems that there is no association between APOE and the occurrence of delirium. We suggest that further studies are needed with greater number of patients to clarify any association as well as to examine for other patterns of association including relevance for subgroups of patients who develop delirium and for effects on the phenotype of delirium and the outcomes.

Critical Illness Brain Injury

A growing body of literature has shown that survivors of critical illness often struggle with cognitive impairment that persists months to years after hospital discharge. We describe the epidemiology of this form of cognitive impairment-which we refer to as critical illness brain injury-and review the history and maturation of the investigation of this previously unrecognized, yet common problem. We then review the characteristics of critical illness brain injury, which can vary in severity and typically affects multiple domains of cognition. Finally, we examine known risk factors for critical illness brain injury and, based on these data, suggest approaches to patient management.

The utility of the clock drawing test in detection of delirium in elderly hospitalised patients

OBJECTIVES

Delirium is common neuropsychiatric condition among elderly inpatients. The clock drawing test (CDT) has been used widely as bedside screening tool in assessing cognitive impairment in elderly people. Previous studies which evaluate its usefulness in delirium reported conflicting results. The objective of this study was to evaluate the utility of CDT to detect delirium in elderly medical patients.

METHOD

Prospective, observational, longitudinal study. All acute medical admissions 70 years of age and above were approached within 72 hours of admission for recruitment. Patients eligible for inclusion were assessed four times, twice weekly during admission. Assessment included Confusion Assessment Method (CAM), Delirium Rating Scale (DRS-98R), Montreal Cognitive Assessment (MoCA), Acute Physiology and Chronic Health Evaluation II (APACHE) II, and CDT. Data was analysed using a linear mixed effect model.

RESULTS

Three hundred and twenty-three assessments with the CDT were performed on 200 subjects (50% male, mean age 81.13; standard deviation: 6.45). The overall rate of delirium (CAM+) during hospitalisation was 23%. There was a significant negative correlation between the CDT and DRS-R98 scores (Pearson correlation r = -0.618, p < 0.001), CDT and CAM (Spearman's rho = -0.402, p < 0.001) and CDT and total MoCA score (Pearson's r = 0.767, p < 0.001). However, when the data were analysed longitudinally controlling for all the factors, we found that cognitive function and age were significant factors associated with CDT scores (p < .0001): neither the presence nor the severity of delirium had an additional significant effect on the CDT.

CONCLUSION

CDT score reflects cognitive impairment, independently of the presence or severity of delirium. The CDT is not a suitable test for delirium in hospitalised elderly patients.

The short-term and long-term relationship between delirium and cognitive trajectory in older surgical patients

INTRODUCTION

As the relationship between delirium and long-term cognitive decline has not been well-explored, we evaluated this association in a prospective study.

METHODS

SAGES is an ongoing study involving 560 adults age 70 years or more without dementia scheduled for major surgery. Delirium was assessed daily in the postoperative period using the Confusion Assessment Method. General Cognitive Performance (GCP) and the Informant Questionnaire for Cognitive Decline in the Elderly were assessed preoperatively then repeatedly out to 36 months.

RESULTS

On average, patients with postoperative delirium had significantly lower preoperative cognitive performance, greater immediate (1 month) impairment, equivalent recovery at 2 months, and significantly greater long-term cognitive decline relative to the nondelirium group. Proxy reports corroborated the clinical significance of the long-term cognitive decline in delirious patients.

DISCUSSION

Cognitive decline after surgery is biphasic and accelerated among persons with delirium. The pace of long-term decline is similar to that seen with mild cognitive impairment.

Delirium, how does it end? Mortality as an outcome in older medical inpatients

OBJECTIVES

Delirium is associated with poor outcomes. Previous research in delirium and mortality gave rather inconclusive results. This study aims to find out the rates of mortality at 1 year and the factors associated with it in a cohort of hospitalized older patients.

METHOD

Prospective, observational, longitudinal study. All acute medical admissions 70 years of age and above were approached within 72 h of admission. Exclusion criteria are as follows: severe aphasia; intubation; severe sensory problems; and non-English speakers. Patients eligible for inclusion were assessed four times, twice weekly during admission. Delirium was defined using the Confusion Assessment Method.

RESULTS

Two hundred patients were recruited. The mean age was 81.13 years (SD = 6.45; minimum 70 and maximum 100 years old), of which 100 (50%) participants were women. One hundred fifty-four (77%) patients never developed delirium during hospitalization. The overall rate of delirium was 23%. A total of 55 (27.5%) patients died during the 1-year follow-up. Although at 1-year follow-up, more people with delirium died (χ(2) = 9.873, df:1, p = 0.002), survival analysis after controlling for other variables showed that mortality was independent of delirium and that severity of illness, longer hospital stay and cognition were significant risk factors for mortality.

CONCLUSION

Although the sample size precludes drawing any definite conclusion, the findings of this study suggest that delirium is not an important risk factor for subsequent mortality. Perhaps delirium and cognitive impairment share common pathophysiological pathways that are related to mortality and in which the currently used methods cannot detect.

Perioperative sleep apnea: a real problem or did we invent a new disease?

Depending on the subpopulation, obstructive sleep apnea (OSA) can affect more than 75% of surgical patients. An increasing body of evidence supports the association between OSA  and perioperative complications, but some data indicate important perioperative outcomes do not differ between patients with and without OSA. In this review we will provide an overview of the pathophysiology of sleep apnea and the risk factors for perioperative complications related to sleep apnea. We also discuss a clinical algorithm for the identification and management of OSA patients facing surgery.

The Association of Brain MRI Characteristics and Postoperative Delirium in Cardiac Surgery Patients

PURPOSE

Delirium is common after cardiac surgery and is associated with adverse consequences, including cognitive decline. Identification of vulnerable older adults might allow for early implementation of delirium-prevention strategies. Brain MRI findings provide insight into structural brain changes that may identify vulnerable patients. The purpose of this study was to examine the association between brain MRI characteristics potentially associated with delirium vulnerability and the development of postoperative delirium in a nested cohort of patients undergoing cardiac surgery.

METHODS

We identified 79 cardiac surgery patients who had brain MRI imaging after cardiac surgery, as part of an ongoing randomized trial evaluating the efficacy of blood pressure management based on cerebral autoregulation monitoring versus standard management for improving neurological outcomes. Cerebral lateral ventricular size, cortical sulcal width, and white matter hyperintensities (WMH) on brain MRI scans were graded on a validated 0 to 9 scale, and categorized into tertiles. New ischemic lesions were characterized as present or absent. Delirium was assessed using a validated chart-review. Neuropsychological testing performed before surgery was used to establish preoperative cognitive baseline. Multivariable logistic regression was used to assess the independent association between MRI characteristics and postoperative delirium.

FINDINGS

The average age of patients was 70.1 ± 7.8 years old, and 72% were male. Twenty-eight of 79 (35.4%) patients developed postoperative delirium. Patients with delirium had higher unadjusted ventricular size (median 4 vs. 3, P = 0.003), and there was a trend towards higher sulcal sizes and WMH grades. Increasing tertiles of ventricular size (Odds Ratio [OR] 3.59; 95% Confidence Interval [CI] 1.59-8.12; P = 0.002) and sulcal size (OR 2.15; 95%CI 1.13-4.12; P = 0.02) were associated with postoperative delirium, with a trend for tertiles of WMH grade (OR 1.91; 95%CI 0.99-3.68; P = 0.05). In multivariable models adjusted for logistic EuroSCORE, baseline cognitive status, bypass time, and any postoperative complication, each tertile of ventricular size was associated with increased odds of postoperative delirium (OR 3.23 per tertile increase in ventricular size; 95%CI 1.21-8.60; P = 0.02). There were no differences in odds of delirium by tertiles of sulcal grade, tertiles of white matter grade, or presence of new ischemic lesions, in adjusted models.

IMPLICATIONS

Increased brain ventricular size was independently associated with delirium after cardiac surgery. These results suggest that cerebral atrophy may contribute to increased vulnerability for postoperative delirium. Baseline brain MRIs may be useful in identifying cardiac surgery patients at high risk for postoperative delirium, who might benefit from targeted perioperative approaches to prevent delirium. ClinicalTrials.gov identifier: NCT00981474.

Systemic inflammation and microglial activation: systematic review of animal experiments

Background

Animal studies show that peripheral inflammatory stimuli may activate microglial cells in the brain implicating an important role for microglia in sepsis-associated delirium. We systematically reviewed animal experiments related to the effects of systemic inflammation on the microglial and inflammatory response in the brain.

Methods

We searched PubMed between January 1, 1950 and December 1, 2013 and Embase between January 1, 1988 and December 1, 2013 for animal studies on the influence of peripheral inflammatory stimuli on microglia and the brain. Identified studies were systematically scored on methodological quality. Two investigators extracted independently data on animal species, gender, age, and genetic background; number of animals; infectious stimulus; microglial cells; and other inflammatory parameters in the brain, including methods, time points after inoculation, and brain regions.

Results

Fifty-one studies were identified of which the majority was performed in mice (n = 30) or in rats (n = 19). Lipopolysaccharide (LPS) (dose ranging between 0.33 and 200 mg/kg) was used as a peripheral infectious stimulus in 39 studies (76 %), and live or heat-killed pathogens were used in 12 studies (24 %). Information about animal characteristics such as species, strain, sex, age, and weight were defined in 41 studies (80 %), and complete methods of the disease model were described in 35 studies (68 %). Studies were also heterogeneous with respect to methods used to assess microglial activation; markers used mostly were the ionized calcium binding adaptor molecule-1 (Iba-1), cluster of differentiation 68 (CD68), and CD11b. After LPS challenge microglial activation was seen 6 h after challenge and remained present for at least 3 days. Live Escherichia coli resulted in microglial activation after 2 days, and heat-killed bacteria after 2 weeks. Concomitant with microglial response, inflammatory parameters in the brain were reviewed in 23 of 51 studies (45 %). Microglial activation was associated with an increase in Toll-like receptor (TLR-2 and TLR-4), tumor necrosis factor alpha (TNF-α), and interleukin 1 beta (IL-1β) messenger ribonucleic acid (mRNA) expression or protein levels.

Interpretation

Animal experiments robustly showed that peripheral inflammatory stimuli cause microglial activation. We observed distinct differences in microglial activation between systemic stimulation with (supranatural doses) LPS and live or heat-killed bacteria.

Functional brain imaging in survivors of critical illness: A prospective feasibility study and exploration of the association between delirium and brain activation patterns

PURPOSE

We undertook this pilot prospective cohort investigation to examine the feasibility of functional magnetic resonance imaging (fMRI) assessments in survivors of critical illness and to analyze potential associations between delirium and brain activation patterns observed during a working memory task (N-back) at hospital discharge and 3-month follow-up.

MATERIALS AND METHODS

At hospital discharge and 3 months later, fMRI assessed subjects' functional activity during an N-back task. Multiple linear regression was used to examine associations between duration of delirium and brain activity, and elastic net regression was used to assess the relationship between brain activation patterns at 3 months and cognitive outcomes at 12 months.

RESULTS

Of 47 patients who underwent fMRI at discharge, 38 (80%) completed the protocol; of 37 who underwent fMRI at 3 months, 34 (91%) completed the protocol. At discharge, the mean (SD) percentage of correct responses on the most challenging version (the N2 version) of the N-back task was 70.4 (23.2; range of 20-100) compared with 76 (23.4; range of 33-100) at 3 months. No association was observed between delirium duration in the hospital and brain region activity in any brain region at discharge or 3 months after adjusting for relevant covariates (P values across all 11 brain regions of interest were >.25).

CONCLUSIONS

Our data support the feasibility of using fMRI in survivors of critical illness at 3-month follow-up but not at discharge. In this small study, delirium was not associated with distinct or abnormal brain activation patterns, although overall performance on a cognitive task of working memory was poorer than observed in other cohorts of individuals with medically related executive dysfunction, mild cognitive impairment, and mild traumatic brain injury.

Is there a role for monocyte chemoattractant protein-1 in delirium? Novel observations in elderly hip fracture patients

Background

Delirium is common, associated with poor outcome, but its pathophysiology remains obscure. The aim of the present study was to study a possible role of monocyte chemoattractant protein-1 (MCP-1) in the development of delirium.

Findings

A prospective cohort of 19 hip fracture patients (median age 83 years) were screened for delirium daily by validated methods. MCP-1 was measured on arrival and postoperatively. The number of patients with a raise in MCP-1 was statistically significantly higher in the group with delirium in the postoperative phase compared to the no-delirium group (5/6 vs. 1/7, p = .03).

Conclusions

MCP-1 might play a role in the development of delirium.

Pediatric delirium and associated risk factors: a single-center prospective observational study

OBJECTIVE

To describe a single-institution pilot study regarding prevalence and risk factors for delirium in critically ill children.

DESIGN

A prospective observational study, with secondary analysis of data collected during the validation of a pediatric delirium screening tool, the Cornell Assessment of Pediatric Delirium.

SETTING

This study took place in the PICU at an urban academic medical center.

PATIENTS

Ninety-nine consecutive patients, ages newborn to 21 years.

INTERVENTION

Subjects underwent a psychiatric evaluation for delirium based on the Diagnostic and Statistical Manual IV criteria.

MEASUREMENTS AND MAIN RESULTS

Prevalence of delirium in this sample was 21%. In multivariate analysis, risk factors associated with the diagnosis of delirium were presence of developmental delay, need for mechanical ventilation, and age 2-5 years.

CONCLUSIONS

In our institution, pediatric delirium is a prevalent problem, with identifiable risk factors. Further large-scale prospective studies are required to explore multi-institutional prevalence, modifiable risk factors, therapeutic interventions, and effect on long-term outcomes.

Delirium transitions in the medical ICU: exploring the role of sleep quality and other factors

OBJECTIVES

Disrupted sleep is a common and potentially modifiable risk factor for delirium in the ICU. As part of a quality improvement project to promote sleep in the ICU, we examined the association of perceived sleep quality ratings and other patient and ICU risk factors with daily transition to delirium.

DESIGN

Secondary analysis of prospective observational study.

SETTING

Medical ICU over a 201-day period.

PATIENTS

Two hundred twenty-three patients with greater than or equal to one night in the medical ICU in between two consecutive days of delirium assessment.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Daily perceived sleep quality ratings were measured using the Richards-Campbell Sleep Questionnaire. Delirium was measured twice daily using the Confusion Assessment Method for the ICU. Other covariates evaluated included age, sex, race, ICU admission diagnosis, nighttime mechanical ventilation status, prior day's delirium status, and daily sedation using benzodiazepines and opioids, via both bolus and continuous infusion. Perceived sleep quality was similar in patients who were ever versus never delirious in the ICU (median [interquartile range] ratings, 58 [35-76] vs 57 [33-78], respectively; p = 0.71), and perceived sleep quality was unrelated to delirium transition (adjusted odds ratio, 1.00; 95% CI, 0.99-1.00). In mechanically ventilated patients, receipt of a continuous benzodiazepine and/or opioid infusion was associated with delirium transition (adjusted odds ratio, 4.02; 95% CI, 2.19-7.38; p < 0.001), and patients reporting use of pharmacological sleep aids at home were less likely to transition to delirium (adjusted odds ratio, 0.40; 95% CI, 0.20-0.80; p = 0.01).

CONCLUSIONS

We found no association between daily perceived sleep quality ratings and transition to delirium. Infusion of benzodiazepine and/or opioid medications was strongly associated with transition to delirium in the ICU in mechanically ventilated patients and is an important, modifiable risk factor for delirium in critically ill patients.

Delirium in intensive care: an under-diagnosed reality

Delirium occurs in up to 80% of patients admitted to intensive care units. Although under-diagnosed, delirium is associated with a significant increase in morbidity and mortality in critical patients. Here, we review the main risk factors, clinical manifestations and preventative and therapeutic approaches (pharmacological and non-pharmacological) for this illness.

Evaluation and management of the elderly patient presenting with cognitive complaints

Cognitive complaints are common in the geriatric population. Older adults should routinely be asked about any concerns about their memory or thinking, and any cognitive complaint from the patient or an informant should be evaluated rather than be attributed to aging. Several screening instruments are available to document objective impairments and guide further evaluation. Management goals for patients with cognitive impairment are focused on maintaining function and independence, providing caregiver support, and advance care planning. There are currently no treatments to effectively prevent or treat dementia. Increasing appreciation of the heterogeneity of Alzheimer disease may lead to novel treatment approaches.

Defining 'recovery' for delirium research: a systematic review

BACKGROUND

Delirium is a common neuropsychiatric disorder. The natural course is of an acute, fluctuating and often transient condition; however, accumulating evidence suggests that delirium can be associated with incomplete recovery. Despite a growing body of research, a lack of clarity exists regarding definition and outcomes.

OBJECTIVE

To clarify the definition of recovery of delirium used in the literature.

METHODS

A Medline search was performed using relevant keywords. Studies were included if they were in English, provided any definition of recovery and were longitudinal. Excluded articles were duplicated studies, case studies, review articles or articles related to alcohol, children, subsyndromal delirium only or those investigating core symptoms such as function.

RESULTS

Fifty-six studies met the inclusion criteria. Only two studies used clinical criteria alone for the diagnosis of delirium; most studies used at least one validated scale-either categorical or continuous severity scales. A variety of 16 different terms were used to define the 'recovery of delirium'. The definitions of each term also varied. Studies using severity scales used either cut-off points or percentage reduction between assessments, while others using dichotomous scales (yes/no) defined recovery as one or more days of negative delirium.

CONCLUSION

An agreed terminology to define recovery in delirium is required. A distinction should also be made between symptomatic and overall recovery, as well as between long- and short-term outcomes. It is proposed that cognitive recovery should be central to defining recovery in delirium.