History of a suspected delirium is more common in dementia with Lewy bodies than Alzheimer's disease: a retrospective study

Differentiating Prodromal Dementia with Lewy Bodies from Prodromal Alzheimer's Disease: A Pragmatic Review for Clinicians

This pragmatic review synthesises the current understanding of prodromal dementia with Lewy bodies (pDLB) and prodromal Alzheimer's disease (pAD), including clinical presentations, neuropsychological profiles, neuropsychiatric symptoms, biomarkers, and indications for disease management. The core clinical features of dementia with Lewy bodies (DLB)-parkinsonism, complex visual hallucinations, cognitive fluctuations, and REM sleep behaviour disorder are common prodromal symptoms. Supportive clinical features of pDLB include severe neuroleptic sensitivity, as well as autonomic and neuropsychiatric symptoms. The neuropsychological profile in mild cognitive impairment attributable to Lewy body pathology (MCI-LB) tends to include impairment in visuospatial skills and executive functioning, distinguishing it from MCI due to AD, which typically presents with impairment in memory. pDLB may present with cognitive impairment, psychiatric symptoms, and/or recurrent episodes of delirium, indicating that it is not necessarily synonymous with MCI-LB. Imaging, fluid and other biomarkers may play a crucial role in differentiating pDLB from pAD. The current MCI-LB criteria recognise low dopamine transporter uptake using positron emission tomography or single photon emission computed tomography (SPECT), loss of REM atonia on polysomnography, and sympathetic cardiac denervation using meta-iodobenzylguanidine SPECT as indicative biomarkers with slowing of dominant frequency on EEG among others as supportive biomarkers. This review also highlights the emergence of fluid and skin-based biomarkers. There is little research evidence for the treatment of pDLB, but pharmacological and non-pharmacological treatments for DLB may be discussed with patients. Non-pharmacological interventions such as diet, exercise, and cognitive stimulation may provide benefit, while evaluation and management of contributing factors like medications and sleep disturbances are vital. There is a need to expand research across diverse patient populations to address existing disparities in clinical trial participation. In conclusion, an early and accurate diagnosis of pDLB or pAD presents an opportunity for tailored interventions, improved healthcare outcomes, and enhanced quality of life for patients and care partners.

Risk factors, preventive interventions, overlapping symptoms, and clinical measures of delirium in elderly patients

Delirium is an acute reversible neuropsychiatric syndrome caused by multiple factors. It is associated with many adverse clinical outcomes including cognitive impairment, functional decline, prolonged hospitalization, and increased nursing service. The prevalence of delirium was high in department of cardiology, geriatric, and intensive care unit of hospital. With the increase in the aged population, further increases in delirium seem likely. However, it remains poorly recognized in the clinical practice. This article comprehensively discusses the latest research perspectives on the epidemiological data, risk factors, preventive interventions, overlapping symptoms, and clinical measures of delirium, including specific measures to manage delirium in clinical real-world situations. This article helps readers improve their knowledge and understanding of delirium and helps clinicians quickly identify and implement timely therapeutic measures to address various delirium subtypes that occur in the clinical settings to ensure patients are treated as aggressively as possible.

Characterising the prodromal phase in dementia with Lewy bodies

INTRODUCTION

Three presentations of prodromal dementia with Lewy bodies (DLB) have recently been proposed. This study investigates the frequency of symptoms in the prodromal phase of DLB.

METHOD

Patients diagnosed with DLB between the 1^st of February 2017 and 1^st of February 2021 were retrospectively identified and matched to a group of patients diagnosed with Alzheimer's disease (AD). Patient case files were reviewed identifying the first symptoms and symptoms in the prodromal phase (cognitive impairment, psychiatric symptoms, delirium/acute confusional episodes, RBD, motor symptoms indicative of Parkinson's disease, anosmia, and autonomic dysfunction).

RESULTS

A total of 166 DLB patient and 168 AD patients were included. Of the proposed presentations in patients diagnosed with DLB, 30% presented with cognitive impairment at onset in isolation, 6% with psychiatric symptoms, and 2% with delirium/acute confusional episodes. Prodromal DLB was more likely to present with no cognitive symptoms at initial presentation (38% vs 10%) and was more likely to involve other symptoms (69% vs 26%). Of other possible presentations, Rapid eye-movement sleep Behaviour Disorder (RBD) was found at onset in 22% with a mean prodromal length of 8.4 years (all symptoms: mean 4.3 years, SD 5.8).

CONCLUSION

We found some supportive evidence of the proposed cognitive and psychiatric presentations of prodromal DLB. Our findings build on previous findings that an RBD presentation exist, and further research is needed to characterise this presentation.

Challenges in diagnosis and management of delirium in Lewy body disease

BACKGROUND

Delirium is an acute onset and fluctuating impairment of cognition, attention and arousal, often precipitated by acute illness. Lewy body disease (LBD) is an umbrella term for a range of clinical conditions, including Parkinson's disease dementia (PDD) and dementia with Lewy bodies (DLB). People living with LBD seem to be more susceptible to delirium than those with other subtypes of dementia.

AIM

To describe the challenges in clinical diagnosis and management of LBD.

METHODS

A systematic review of published literature on diagnosis and management of delirium in LBD.

RESULTS

Delirium is particularly challenging to diagnose in LBD as many of the clinical characteristics which define delirium such as inattention, fluctuating arousal, complex visual hallucinations and delusions, are also common to LBD. Distinguishing delirium from LBD can be very difficult clinically especially in the prodromal stages. Both under and over diagnosis of delirium, and under and over treatment of the symptoms have the potential to compromise the care and safety of people with a diagnosed or undiagnosed LBD. Clinicians are currently working with an extremely limited set of evidence-based management options for those with delirium in the context of a LBD diagnosis. For patients with LBD and their families this is an area of clinical practice that needs focused research.

EEG Abnormalities During Delirium as a Prodromal Feature of Dementia with Lewy Bodies: A Case Report

Background: A 79-year-old woman was admitted to the Neurology Clinic of the University of Chieti-Pescara for a syncope. At admission, the occurrence of an acute stroke was ruled out. Her cognitive status was unimpaired. After three days from the hospitalization, the patient experienced an episode of mixed delirium. Objective: The present case report shows a case of delirium-onset dementia with Lewy bodies (DLB) with a specific electroencephalographic (EEG) pattern from its prodromal stage. Methods: Delirium was assessed by 4AT test. During the hospitalization, the patient underwent a quantitative EEG (QEEG) with spectral analysis. At six months from the episode of delirium, she was tested by neuropsychological evaluation, QEEG, and 18F-fluorodeoxyglucose PET/CT to assess the onset of a possible cognitive decline. Results: At baseline, the QEEG exam showed a dominant frequency (DF) in the pre-alpha band (7.5 Hz) with a dominant frequency variability (DFV) of 2 Hz. This pattern is typical of DLB at early stage. After six months, she reported attention deficits in association with cognitive fluctuation and REM sleep behavior disorder. The neurological examination revealed signs of parkinsonism. Cognitive status resulted to be impaired (MoCA = 15/30). QEEG recording confirmed the presence of a DLB-typical pattern (DF = 7.5 Hz, DFV = 2.5 Hz). The 18F-FDG-PET/CT showed a moderate bilateral posterior hypometabolism (occipital and temporal cortex), with relative sparing of the posterior cingulate cortex compared to cuneus/precuneus (Cingulate Island sign), and mild bilateral hypometabolism in frontal regions (suggestive of a DLB diagnosis). Conclusion: EEGs may represent supportive and validated biomarkers for delirium-onset prodromal DLB.

Correlates of Conversion from Mild Cognitive Impairment to Dementia with Lewy Bodies: Data from the National Alzheimer's Coordinating Center

BACKGROUND

Many patients with dementia with Lewy bodies (DLB) miss out on the best standards of care and psychosocial support due to diagnostic delays or inaccuracies following symptom onset.

OBJECTIVE

This study seeks to identify baseline characteristics in individuals with mild cognitive impairment (MCI) that correlate with eventual conversion to DLB or Alzheimer's disease (AD).

METHODS

Baseline neuropsychological and neuropsychiatric data were analyzed in National Alzheimer's Coordinating Center participants who completed the Uniform Data Set between 2006 and 2020 and subsequently converted from MCI to DLB or AD (n = 1632).

RESULTS

Only 6% of participants with MCI converted to DLB. Among those who converted to DLB, multidomain amnestic MCI (aMCI) was the most common subtype at study entry. As part of logistic regression analyses, odds ratios (ORs) were estimated for conversion to DLB versus AD based on study-entry characteristics, adjusting for age, sex, education, and years to diagnosis. The strongest predictors of conversion to DLB (p≤0.0001) were nonamnestic MCI versus aMCI (OR 8.2, CI [5.0, 14]), multidomain MCI versus single-domain MCI (OR 2.7, CI [1.7. 4.2]), male sex (OR 4.2, CI [2.5, 7.1]), and presence of nighttime behaviors (OR 4.4 CI [2.8, 6.9]).

CONCLUSION

A diagnosis of prodromal DLB should be considered in individuals with MCI who present with prominent executive/visuospatial deficits, neuropsychiatric symptoms, and less memory impairment. Early diagnosis of DLB may guide treatment planning, including the avoidance of antipsychotic medications in patients who develop psychotic symptoms, caregiver support, and initiation of early treatment(s) once medications become available.

The temporal onset of the core features in dementia with Lewy bodies

Introduction

We examined the temporal sequence of the core features in probable dementia with Lewy bodies (DLB).

Methods

In 488 patients with probable DLB, the onset of each core feature and time to diagnosis was determined for men and women, and a pathologic subgroup (n = 209).

Results

REM sleep behavior disorder (RBD) developed before the other core features in men and women. Men were more likely to have RBD and were diagnosed with probable DLB earlier than women. Visual hallucinations developed after the other core features in men, but in women, they appeared earlier and concurrently with fluctuations and parkinsonism. Women were older and more cognitively impaired at first visit, were less likely to have RBD, more likely to be diagnosed with probable DLB later than men, and more likely to have neocortical tangles.

Discussion

An earlier latency to probable DLB was associated with men, RBD, and Lewy body disease without neocortical tangles.

Cerebrospinal fluid catecholamines in delirium and dementia

Dopamine and noradrenaline are functionally connected to delirium and have been targets for pharmacological interventions but the biochemical evidence to support this notion is limited. To study the CSF levels of dopamine, noradrenaline and the third catecholamine adrenaline in delirium and dementia, these were quantified in three patient cohorts: (i) cognitively normal elderly patients (n = 122); (ii) hip fracture patients with or without delirium and dementia (n = 118); and (iii) patients with delirium precipitated by another medical condition (medical delirium, n = 26). Delirium was assessed by the Confusion Assessment Method. The hip fracture cohort had higher CSF levels of noradrenaline and adrenaline than the two other cohorts (both P < 0.001). Within the hip fracture cohort those with delirium (n = 65) had lower CSF adrenaline and dopamine levels than those without delirium (n = 52, P = 0.03, P = 0.002). Similarly, the medical delirium patients had lower CSF dopamine levels than the cognitively normal elderly (P < 0.001). Age did not correlate with the CSF catecholamine levels. These findings with lower CSF dopamine levels in hip fracture- and medical delirium patients challenge the theory of dopamine excess in delirium and question use of antipsychotics in delirium. The use of alpha-2 agonists with the potential to reduce noradrenaline release needs further examination.

Delirium in the acute hospital setting: the role of psychiatry

In this overview we discuss the role of psychiatry in managing delirium in acute hospital admissions. We briefly discuss the role psychiatry can offer in four main domains: (a) assessment; (b) management; (c) recovery; and (d) paradigm, education and research. In the assessment section we discuss accurately detecting delirium in the context of comorbid mixed neuropsychiatric syndromes, including depression and dementia, and the clinical importance of delirium subtyping. The management section briefly outlines pharmacological and non-pharmacological approaches to delirium and their evidence-based rationale. The recovery section focuses on the effect delirium can have on cognitive decline, mental health and long-term health, including functional outcome and need for institutional care after hospital discharge. Finally, we outline the role of psychiatry in delirium research and education. We hope that this article will encourage clinicians to reflect on their current practice and consider holistic and evidence-based care for this vulnerable population in the acute hospital setting.

Fluctuating cognition in the Lewy body dementias

Fluctuating cognition is a core diagnostic feature of dementia with Lewy bodies and is also a key clinical feature of Parkinson's disease dementia. These dementias share common pathological features and are referred to as Lewy body dementias. Whilst highly prevalent in Lewy body dementia, with up to 90% of patients experiencing the symptom at some point in the disease trajectory, clinical identification of fluctuating cognition is often challenging. Furthermore, its underlying pathophysiological processes remain unclear. However, neuroimaging and neurophysiological techniques have recently provided insight into potential drivers of the phenomenon. In this update, we review data pertaining to clinical features and underlying mechanisms of fluctuating cognition in Lewy body dementia. We collate evidence for different proposed aetiologies: fluctuating cognition as an attentional disorder, as a consequence of loss of cholinergic drive, as a manifestation of failure in neuronal efficiency and synchrony, and as a disorder of sleep/arousal. We also review data relating to putative mechanisms that have received less attention to date. Increased understanding of fluctuating cognition may help to illuminate pathophysiological mechanisms in cognitive processing in Lewy body dementia, guide future research, and facilitate the design of targeted therapeutic approaches.

Research criteria for the diagnosis of prodromal dementia with Lewy bodies

The prodromal phase of dementia with Lewy bodies (DLB) includes (1) mild cognitive impairment (MCI), (2) delirium-onset, and (3) psychiatric-onset presentations. The purpose of our review is to determine whether there is sufficient information yet available to justify development of diagnostic criteria for each of these. Our goal is to achieve evidence-based recommendations for the recognition of DLB at a predementia, symptomatic stage. We propose operationalized diagnostic criteria for probable and possible mild cognitive impairment with Lewy bodies, which are intended for use in research settings pending validation for use in clinical practice. They are compatible with current criteria for other prodromal neurodegenerative disorders including Alzheimer and Parkinson disease. Although there is still insufficient evidence to propose formal criteria for delirium-onset and psychiatric-onset presentations of DLB, we feel that it is important to characterize them, raising the index of diagnostic suspicion and prioritizing them for further investigation.

Fact-finding survey on diagnostic procedures and therapeutic interventions for parkinsonism accompanying dementia with Lewy bodies

BACKGROUND

We performed a questionnaire survey of medical doctors engaged in the management of dementia to identify the actual status of treatment for dementia with Lewy bodies (DLB) in Japan.

METHODS

Among participating medical doctors, we selected neurologists (Group N) and psychiatrists (Group P) because these physicians are usually involved in the management of DLB patients. The two groups were compared based on their diagnosis and treatment of DLB and in particular, parkinsonism.

RESULTS

Neurological examinations and biomarker tests were less frequently performed by Group P than Group N. Antipsychotics and other psychotropics excluding anti-dementia drugs were significantly more frequently administered by Group P than Group N. The proportion of physicians who selected L-dopa as a first-line therapy for parkinsonism was significantly higher in Group N than in Group P. Despite these between-group differences, the following findings were common to the two groups: there was a discrepancy between the symptom that patients expressed the greatest desire to treat, and the awareness of physicians regarding the treatment of these symptoms; the initial agent was L-dopa; and physicians exercised caution against the occurrence of hallucinations, delusions, and other adverse drug reactions.

CONCLUSIONS

The results of the present survey offer valuable insight for the formulation of future DLB therapeutic strategies.

A survey of doctors on diagnosis and treatment of dementia with Lewy bodies: examination and treatment of behavioural and psychological symptoms

BACKGROUND

Dementia with Lewy bodies (DLB) is a progressive form of dementia, accompanied by a range of behavioural and psychological symptoms. The aim of this study was to identify current clinical practice for the treatment of DLB in Japan.

METHODS

We conducted a survey of medical doctors engaged in the management of dementia in Japan. Participants were divided into two groups: psychiatrists (Group P) and neurologists or neurosurgeons (Group NS). Doctors completed a questionnaire and we analysed their responses to compare the two groups with regard to diagnosis and treatment of DLB, and in particular the treatment of behavioural and psychological symptoms of dementia (BPSD).

RESULTS

Responses suggested that Group P conducted biomarker examinations less frequently and decided on their own therapeutic strategies more frequently than did Group NS. Both groups most frequently selected hallucinations/delusions as the symptoms given highest treatment priority. More than 70% of respondents in both groups reported having difficulties in treating BPSD. Atypical antipsychotics were more frequently prescribed by Group P, but were also prescribed in 70% of patients in Group NS. A third of patients received atypical antipsychotics for more than 1 year.

CONCLUSIONS

The responses to this survey highlighted the difficulties faced by clinicians managing patients with DLB and identified the need to effectively treat BPSD in such patients.

The Incidence of Recorded Delirium Episodes Before and After Dementia Diagnosis: Differences Between Dementia With Lewy Bodies and Alzheimer's Disease

OBJECTIVES

To describe the incidence of delirium recording before and after a diagnosis of dementia is established in patients with dementia with Lewy bodies (DLB) and compare findings to a matched cohort of patients with Alzheimer's disease (AD).

DESIGN

Retrospective cohort study.

SETTING AND PARTICIPANTS

A cohort of patients with dementia from a large mental health and dementia care database in South London, linked to hospitalization and mortality data. We identified 194 patients with DLB and 1:4 matched these with 776 patients diagnosed with AD on age, gender, and cognitive status.

MEASURES

We identified delirium episodes recorded in mental health and hospital records from 1 year before to 1 year after dementia diagnosis. Using dementia diagnosis as an index date we additionally followed patients until first episode of delirium, death or a censoring point without restricting the observation period.

RESULTS

Patients with DLB had significantly more episodes of delirium recorded in the year before dementia diagnosis than patients with AD (incidence rate 17.6 vs 3.2 per 100 person-years; P < .001). Whereas the incidence of recording of delirium episodes reduced substantially in patients with DLB after dementia diagnosis, it remained significantly higher than in patients with AD (incidence rate 6.2 vs 2.3 per 100 person-years; P = .032). Cox regression models indicate that patients with DLB remain at a higher risk of delirium than patients with AD after a dementia diagnosis.

CONCLUSIONS/RELEVANCE

Establishing a diagnosis of dementia reduces episodes classified as delirium in patients with DLB and might lead to fewer potentially harmful interventions such as hospitalization or use of antipsychotic medication.

Lewy Body Dementia

Dementia with Lewy bodies (DLB) is the second most common neurodegenerative dementia following Alzheimer disease. It stems from the formation of Lewy bodies, which contain aggregates of the misfolded protein, α-synuclein. These deposit in areas of the nervous system and brain, leading to neuronal cell death and causing clinically apparent symptoms. Because of its clinical overlap with other forms of dementia, DLB is often underdiagnosed and misdiagnosed. There is currently no cure for DLB and treatments are aimed at ameliorating specific symptoms.

[Diagnostic of prodromal dementia with Levy bodies]

The issues of diagnosis of prodromal dementia with Lewy bodies are considered. Despite numerous studies using international diagnostic criteria, clinical and diagnosis are often inconsistent. Early and more accurate detection of dementia with Lewy bodies is needed for prognosis, optimal management and effective pharmacotherapy.

Delirium prior to dementia as a clinical phenotype of Lewy body disease: an autopsied case report

Although delirium shares clinical characteristics with dementia with Lewy bodies (DLB), there is limited information regarding the relationship between delirium and Lewy body pathology. Here, we report an 89-year-old Japanese woman with an episode of delirium who was pathologically confirmed to have limbic-type Lewy body disease (LBD). Although she exhibited transient visual hallucinations during the delirium, she had no overt dementia. She developed no core clinical features of DLB and died of pneumonia at the age of 90 years. This autopsied case suggests that delirium may be one of the clinical phenotypes of LBD prior to the onset of dementia.

Synucleinopathies: common features and hippocampal manifestations

Parkinson's disease (PD), dementia with Lewy Bodies (DLB), and multiple system atrophy (MSA) are three major synucleinopathies characterized by α-synuclein-containing inclusions in the brains of patients. Because the cell types and brain structures that are affected vary markedly between the disorders, the patients have different clinical manifestations in addition to some overlapping symptoms, which are the basis for differential diagnosis. Cognitive impairment and depression associated with hippocampal dysfunction are frequently observed in these disorders. While various α-synuclein-containing inclusions are found in the hippocampal formation, increasing evidence supports that small α-synuclein aggregates or oligomers may be the real culprit, causing deficits in neurotransmission and neurogenesis in the hippocampus and related brain regions, which constitute the major mechanism for the hippocampal dysfunctions and associated neuropsychiatric manifestations in synucleinopathies.

ALBA Screening Instrument (ASI): A brief screening tool for Lewy Body Dementia

BACKGROUND

Early detection of neurodegenerative diseases is essential for treatment and proper care of these patients. Screening tools available today are effective for several types of dementia. However, there is no one specific for Lewy Body Dementia (LBD).

OBJECTIVES

The aim of this paper is to present a tool for early detection of LBD, accessible even for non-medical staff.

METHODS

We stratified subjects (MMSE>20) into four groups: health controls (HC), Mild Cognitive Impairment (MCI), LBD and other dementias (Alzheimer and vascular). All subjects (age range 50-90) were examined with a comprehensive neuropsychological and neuropsychiatric evaluation, as well as neuroimaging to differentiate diagnosis between groups, fulfilling corresponding criteria. Both neurologists and neuropsychologists were blind to the performance on clinical evaluations and ASI, respectively. The sensitivity and specificity of the instrument were determined to differentiate LBD from other groups.

RESULTS

We evaluated 427 subjects, 91 HC, 140 with MCI and 196 with dementia. In the dementia group, 75 were diagnosed with LBD and 121 with other dementias. ASI total score was 12.7±0.4 for LBD, 2.9±0.2 for HC, 5±0.7 for MCI, and 5.4±2.6 for other causes of dementia. ROC curve analysis showed a sensitivity of 90.7% and a specificity of 93.6% stands, with 9 as the cutoff with better test performance compared against other groups.

CONCLUSION

ASI is a brief screening tool for LBD with high sensitivity and specificity and useful even for non-medical staff.

The Diagnosis of Delirium Superimposed on Dementia: An Emerging Challenge

Delirium occurring in patients with dementia is referred to as delirium superimposed on dementia (DSD). People who are older with dementia and who are institutionalized are at increased risk of developing delirium when hospitalized. In addition, their prior cognitive impairment makes detecting their delirium a challenge. The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition and the International Statistical Classification of Diseases and Related Health Problems, 10th Revision are considered the standard reference for the diagnosis of delirium and include criteria of impairments in cognitive processes such as attention, additional cognitive disturbances, or altered level of arousal. The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition and the International Statistical Classification of Diseases and Related Health Problems, 10th Revision does not provide guidance regarding specific tests for assessment of the cognitive process impaired in delirium. Importantly, the assessment or inclusion of preexisting cognitive impairment is also not addressed by these standards. The challenge of DSD gets more complex as types of dementia, particularly dementia with Lewy bodies, which has features of both delirium and dementia, are considered. The objective of this article is to critically review key elements for the diagnosis of DSD, including the challenge of neuropsychological assessment in patients with dementia and the influence of particular tests used to diagnose DSD. To address the challenges of DSD diagnosis, we present a framework for guiding the focus of future research efforts to develop a reliable reference standard to diagnose DSD. A key feature of a reliable reference standard will improve the ability to clinically diagnose DSD in facility-based patients and research studies.

Revisiting DLB Diagnosis: A Consideration of Prodromal DLB and of the Diagnostic Overlap With Alzheimer Disease

Efforts to clinically diagnose cases having dementia with Lewy bodies (DLB) identify those with a characteristic clinical syndrome (probable DLB) at the expense of missing an equal, if not greater, number of cases who have atypical presentations thought to be associated with coexisting Alzheimer pathologies. This article argues that further efforts should now be made to characterize this atypical group that constitutes cases previously identified postmortem as the Lewy body variant of Alzheimer disease (AD) or as AD with Lewy bodies. Since such fine distinction is unlikely to be achieved on clinical grounds alone, this new diagnostic category will require robust biomarker validation. Turning to a consideration of early/prodromal diagnosis of both typical and atypical DLB cases, it is suggested that there will be at least 3 prototypical forms-a mild cognitive impairment variant, associated with early visuoperceptual and attentional deficits; a delirium onset DLB with provoked or spontaneous delirium as the presenting features; and a psychiatric disorder DLB with its primary presentation as a late-onset affective disorder or psychosis.

Delirium superimposed on dementia: a survey of delirium specialists shows a lack of consensus in clinical practice and research studies

BACKGROUND

Despite advances in delirium knowledge and the publication of best practice guidelines, uncertainties exist regarding assessment of Delirium Superimposed on Dementia (DSD). An international survey of delirium specialists was undertaken to evaluate current practice.

METHODS

Invitations to participate in an online survey were distributed by email among members of four international delirium associations with additional publication on their websites. The survey covered the assessment and diagnosis of DSD in clinical practice and research studies. Questions were structured around current practice and attitudes.

RESULTS

The 205 responders were mostly confident that they could detect DSD with 60% rating their confidence at 7 or above on a likert scale of 0 (none) to 10 (excellent). Seventy-six percent felt that Dementia with Lewy Bodies (DLB) was the most challenging dementia subtype in which to diagnose DSD. Several scales were used to assess for the presence of DSD including the Confusion Assessment Method (CAM) (54%), DSM-5 criteria (25%) and CAM-ICU (15%). Responders stated that attention (71%), fluctuation in cognitive status (65%), and arousability (41%) were the most clinically useful features to assess when diagnosing DSD. Motor fluctuations were also deemed important but 61% had no specific test to monitor these.

CONCLUSIONS

The largest survey of DSD practice to date demonstrates that despite good levels of confidence in recognizing DSD, there exists a lack of consensus concerning assessment and diagnosis globally. These findings suggest the need for the development of more research leading to precise diagnostic criteria and comprehensive guidelines regarding the assessment and diagnosis of DSD.

Dementia With Lew Body: Impacts of Surgery

Patients who have dementia with Lewy bodies (DLB) and undergo surgery may develop aggravated postoperative cognitive dysfunction or postoperative delirium. Many patients with DLB respond poorly to surgery and anesthesia, and their conditions may worsen if they have other medical complications along with dementia. They may also face high risk of prolonged hospital stay, increased medical problems and/or mortality, causing significant physical, psychosocial, and financial burdens on individuals, family members, and society. Anesthesia, pain medications, old age, and surgery-related stresses are usually held responsible for the complications; however, the exact causes are still not fully understood. Literature on surgery-related complications for patients with DLB appears to be inadequate, and hence the topic merits detailed and systematic research. This article reviews postoperative complications and various surgery-related risk factors for DLB in light of other dementias such as Alzheimer's disease, as their neuropathologic features overlap with those of DLB.

Lewy body dementias

The broad importance of dementia is undisputed, with Alzheimer's disease justifiably getting the most attention. However, dementia with Lewy bodies and Parkinson's disease dementia, now called Lewy body dementias, are the second most common type of degenerative dementia in patients older than 65 years. Despite this, Lewy body dementias receive little attention and patients are often misdiagnosed, leading to less than ideal management. Over the past 10 years, considerable effort has gone into improving diagnostic accuracy by refining diagnostic criteria and using imaging and other biomarkers. Dementia with Lewy bodies and Parkinson's disease dementia share the same pathophysiology, and effective treatments will depend not only on successful treatment of symptoms but also on targeting the pathological mechanisms of disease, ideally before symptoms and clinical signs develop. We summarise the most pertinent progress from the past 10 years, outlining some of the challenges for the future, which will require refinement of diagnosis and clarification of the pathogenesis, leading to disease-modifying treatments.

A new delirium phenotype with rapid high amplitude onset and nearly as rapid reversal: Central Coast Australia Delirium Intervention Study

Background

Traditional models for delirium based on the Diagnostic and Statistical Manual for Mental Disorders and its 1990 offspring, the Confusion Assessment Method (CAM), were not designed to distinguish behavioral and psychological symptoms of dementia from rapid cognitive decline. We examined a new diagnostic criterion for delirium plus exclusion of behavioral and psychological symptoms of dementia and recent inattention with a 25% decline in digit span forward (DSF).

Methods

This was a prospective, randomized controlled trial comparing management of prevalent delirium in general medical with that in geriatric medical wards in a 370-bed hospital north of Sydney. Inclusion criteria were age ≥65 years and prevalent delirium in the emergency department based on: CAM; proof that CAM elements were not better explained by behavioral and psychological symptoms of dementia; proof of recent inattention on DSF; evidence of cognitive decline not due to sedatives or antipsychotics in the emergency department. Measurements included the Instrumental Activities of Daily Living (IADL, 22-item), Selective IADL (8-item), Mini-Mental State Examination, DSF daily, Delirium Index daily, and Apathy Evaluation Scale. Pre-delirium scores from past cognitive tests and best scores were imputed after admission. Relative change (RC) was calculated as absolute change/test range and RC/MPC ratio was calculated as RC after admission/maximal possible change.

Results

A total of 130 subjects were recruited but 14 with subsyndromal delirium were excluded, leaving 116 subjects (mean age 83.6 years). Forty-eight percent had prior dementia. RC from pre-delirium to admission was 42% for the Mini-Mental State Examination, 41% for Selective IADL, 34% for 5-DSF, 54% for 6-DSF, and 37% for the Apathy Evaluation Scale. Improvements after admission (RC and RC/MPC ratios) were 32%/98% for 5-DSF, 54%/82% for 6-DSF, and 45%/80% for the Delirium Index. General medicine and geriatric medicine groups had similar outcomes.

Conclusion

This delirium phenotype selects for a rapid high amplitude critical decline in attention, executive function, IADL, and apathy that recovers almost as rapidly.

The clinical characteristics of dementia with Lewy bodies and a consideration of prodromal diagnosis

Dementia with Lewy bodies (DLB) is the second most common type of degenerative dementia following Alzheimer’s disease (AD). DLB is clinically and pathologically related to Parkinson's disease (PD) and PD dementia, and the three disorders can be viewed as existing on a spectrum of Lewy body disease. In recent years there has been a concerted effort to establish the phenotypes of AD and PD in the prodromal phase (before the respective syndromes of cognitive and motor impairment are expressed). Evidence for the prodromal presentation of DLB is also emerging. This paper briefly reviews what is known about the clinical presentation of prodromal DLB before discussing the pathology of Lewy body disease and how this relates to potential biomarkers of prodromal DLB. The presenting features of DLB can be broadly placed in three categories: cognitive impairment (particularly nonamnestic cognitive impairments), behavioural/psychiatric phenomena (for example, hallucinations, rapid eye movement sleep behaviour disorder (RBD)) and physical symptoms (for example, parkinsonism, decreased sense of smell, autonomic dysfunction). Some noncognitive symptoms such as constipation, RBD, hyposmia and postural dizziness can predate the onset of memory impairment by several years in DLB. Pathological studies of Lewy body disease have found that the earliest sites of involvement are the olfactory bulb, the dorsal motor nucleus of the vagal nerve, the peripheral autonomic nervous system, including the enteric nervous system, and the brainstem. Some of the most promising early markers for DLB include the presence of RBD, autonomic dysfunction or hyposmia, ¹²³I-metaiodobenzylguanidine cardiac scintigraphy, measures of substantia nigra pathology and skin biopsy for α-synuclein in peripheral autonomic nerves. In the absence of disease-modifying therapies, the diagnosis of prodromal DLB is of limited use in the clinic. That said, knowledge of the prodromal development of DLB could help clinicians identify cases of DLB where the diagnosis is uncertain. Prodromal diagnosis is of great importance in research, where identifying Lewy body disease at an earlier stage may allow researchers to investigate the initial phases of dementia pathophysiology, develop treatments designed to interrupt the development of the dementia syndrome and accurately identify the patients most likely to benefit from these treatments.

Lewy body dementia: the impact on patients and caregivers

Lewy body dementia (LBD) is the second most common neurodegenerative dementia in older adults, yet there remains a delay in diagnosis that limits healthcare providers’ ability to maximize therapeutic outcomes and enhance patient and caregiver quality of life. The impact of LBD on patients includes limiting the potential exposure to medications that may cause adverse outcomes, and addressing how the disease manifestations, such as autonomic features and behavior, affect quality of life. LBD impact on caregivers has been discussed to a greater degree in the literature, and there is clear evidence of caregiver burden and grief associated with disease manifestations. Other common caregiving concerns, such as access to care, prevention of hospitalization, managing behavior, and reviewing prognosis and nursing home placement, are important to comprehensively address the needs of patients with LBD and their caregivers.