Non-pharmacological interventions for Lewy body dementia: a systematic review

Efficacy of Nonpharmacological Interventions in Cognitive Impairment: Systematic Review And Network Meta-Analysis

INTRODUCTION

There is currently no known cure for cognitive impairment, which highlights the need to explore other ways of managing this condition. This topic has recently become an area of active research. However, the availability of nonpharmacological options poses a challenge when trying to determine the best treatment for improving cognitive function.

METHODS

We conducted a systematic review and a Bayesian network meta-analysis to compare the effects of nonpharmacological interventions on global cognition in patients with mild cognitive impairment and dementia. The nonpharmacological interventions were classified as aerobic exercise, strength exercise, multicomponent physical exercise, other physical exercises, tai chi, mind-body exercises, traditional cognitive rehabilitation, computer-based cognitive rehabilitation, occupational therapy, music therapy, physical-cognitive rehabilitation, and reminiscence therapy.

RESULTS

Physical-cognitive rehabilitation emerged as the most effective nonpharmacological intervention for enhancing global cognition in patients with unspecified cognitive impairment and dementia, whereas occupational therapy focused on dual-task interventions was found to be the most effective nonpharmacological intervention for mild cognitive impairment.

CONCLUSION

These results underscore the importance of adopting a dual approach to managing cognitive impairment, integrating both cognitive and physical rehabilitation within the same intervention.

'Communication is difficult': Speech, language and communication needs of people with young onset or rarer forms of non-language led dementia

BACKGROUND

People with behavioural variant frontotemporal dementia, Lewy body dementia, posterior cortical atrophy and young onset Alzheimer's disease may experience language and communication difficulties. However, the role of speech and language interventions for people with these non-language led dementias has received little attention.

AIMS

This study aimed to explore the experiences and perspectives of people living with these conditions, and their families, regarding their language and communication difficulties and how speech and language therapy could address these needs.

METHODS

This study employed a qualitative design to explore the experiences of people living with or caring for somebody with behavioural variant frontotemporal dementia, Lewy body dementia, posterior cortical atrophy or young onset Alzheimer's disease, and to understand their opinions about speech and language therapy. Participants were recruited from a support service connected to a dementia clinic to attend one of five focus group meetings. Videorecorded focus groups and interviews were transcribed, and reflexive thematic analysis was used to analyse data from people affected by each type of dementia.

RESULTS

A total of 25 participants were recruited to the study, with representation across the different forms of non-language led dementias. The four main themes identified were: (1) communication difficulties as a key difficulty, (2) loss and loneliness, (3) speech and language therapy, and (4) the role of the caregiver. Sixteen subthemes were also identified which highlighted individual issues across disease types.

DISCUSSION

Although all the forms of dementia studied here are not considered to be language-led, people with these conditions and/or their care partners identified speech, language and communication as common challenges. These communication difficulties were reported to have a negative impact on their social participation and mental health and participants felt speech and language interventions could help. There is a need for research exploring speech and language interventions developed for and with people with non-language led dementias and their care partners, to ensure they meet the needs of the people they are designed for.

WHAT THIS PAPER ADDS

What is already known on the subject People with primary progressive aphasia present with speech, language and communication difficulties, and several speech and language interventions have been developed to meet the needs of this population. However, people with non-language led dementias may also experience speech, language and communication difficulties, and little is known about interventions that may address these difficulties. What this paper adds to existing knowledge People living with or caring for somebody with behavioural variant frontotemporal dementia, Lewy body dementia, posterior cortical atrophy and young onset Alzheimer's disease report experiencing speech, language and communication difficulties that impact on the person with dementia's social participation and mood. Participants in this study also shared their opinions about how speech and language interventions could help, from the earliest stages of the disease. What are the potential or actual clinical implications of this work? Speech and language therapists need to address the individual speech, language and communication needs of people with dementias, even those that are not thought to be language-led. Current speech and language therapy service provision does not meet the needs of people with non-language led dementias and further research is required to develop interventions and services to meet these needs.

Dietary factors and Alzheimer's disease risk: a Mendelian randomization study

BACKGROUND

Prior observational research has investigated the association between dietary patterns and Alzheimer's disease (AD) risk. Nevertheless, due to constraints in past observational studies, establishing a causal link between dietary habits and AD remains challenging.

METHODS

Methodology involved the utilization of extensive cohorts sourced from publicly accessible genome-wide association study (GWAS) datasets of European descent for conducting Mendelian randomization (MR) analyses. The principal analytical technique utilized was the inverse-variance weighted (IVW) method.

RESULTS

The MR analysis conducted in this study found no statistically significant causal association between 20 dietary habits and the risk of AD (All p > 0.05). These results were consistent across various MR methods employed, including MR-Egger, weighted median, simple mode, and weighted mode approaches. Moreover, there was no evidence of horizontal pleiotropy detected (All p > 0.05).

CONCLUSION

In this MR analysis, our finding did not provide evidence to support the causal genetic relationships between dietary habits and AD risk.

Assisted bathing of older adults with dementia: a mixed methods systematic review update

OBJECTIVE

This review update aimed to determine the best strategies for assisted bathing or showering for older adults with dementia.

INTRODUCTION

Assisted bathing is a high-risk activity, as it can trigger agitated behaviors. Assisted bathing of older adults with dementia can create caregiver challenges and stress.

INCLUSION CRITERIA

This review update considered quantitative, qualitative, and mixed methods studies that investigated, firstly, older adults with dementia who required assistance with bathing and, secondly, their caregivers and family members who provided this assistance. The quantitative component considered randomized controlled trials and quasi-experimental studies testing interventions for reducing agitated behaviors in older adults with dementia during bathing, as well as perceived confidence or satisfaction in caregivers. The qualitative component considered studies that reported on experiences of clients or caregivers during the bathing process.

METHODS

A JBI mixed methods review was conducted following the convergent segregated approach. The review considered studies published between 1990 and March 11, 2022. The databases searched were PubMed, CINAHL, and Embase. Gray literature was also searched. Two independent reviewers screened titles and abstracts. Full texts were retrieved for studies that met the inclusion criteria and were assessed further for eligibility. Two reviewers independently assessed the quality of included studies and extracted data using the standardized JBI tools. Due to methodological and clinical heterogeneity, the results were presented narratively in the quantitative section. For the qualitative component, meta-synthesis was conducted following the JBI approach of meta-aggregation. Finally, evidence from the 2 components was integrated following the convergent segregated approach.

RESULTS

Ten quantitative and 4 qualitative studies were included. The methodological quality was poor to moderate in the quantitative studies and moderate to high in the qualitative studies. Results from 3 quantitative studies suggested that providing training to caregivers on person-centered bathing reduced agitated behaviors in older adults with dementia. Other interventions did not show conclusive evidence of their effectiveness in any outcomes of interest. Two synthesized findings highlighted i) the importance of working within each person's reality by having the skills and knowledge required to deliver person-centered assistance and ii) the challenges experienced by caregivers, such as lack of support, time pressure, and safety-related fears. The integrated evidence showed that the quantitative and qualitative components complemented each other to promote the training of caregivers to deliver person-centered bathing.

DISCUSSION

Integrated findings can help inform an evidence-based strategy utilizing a person-centered bathing approach to reduce agitated behaviors in older adults with dementia. Due to the limited number of eligible studies, and the clinical and methodological heterogeneity of included quantitative studies, no statistical pooling was possible. More studies are needed, particularly intervention studies with high methodological quality.

CONCLUSIONS

This review update suggests that providing caregivers with person-centered bathing training should be encouraged prior to bathing older adults with dementia. Caregivers should have the knowledge and skills, such as relevant assessment and communication skills, enabling them to provide effective bathing experiences to older adults living with dementia. Organizations should provide caregivers with appropriate resources and training for bathing older adults with dementia.

REVIEW REGISTRATION

PROSPERO CRD42020208048.

SUPPLEMENTAL DIGITAL CONTENT

A Japanese-language version of the abstract of this review is available as supplemental digital content 1: http://links.lww.com/SRX/A37 .

Case report: Environmental adjustment for visual hallucinations in dementia with Lewy bodies based on photo assessment of the living environment

Background

Visual hallucinations (VH) are associated with visual prediction error in patients with dementia with Lewy bodies (DLB). Given this relationship, environmental adjustments have been suggested, but detailed contents for implementing such environmental adjustments and assessments are poorly documented. This case report preliminarily demonstrates methods for improving VH through our experience with two patients with DLB. We conducted familial interviews to assess the phenomenological features of VH and reviewed photographs of patients' homes to identify the environmental triggers of VH, known as photo assessment of the living environment (PA-LE).

Case description

Patient 1 was a 78-year-old woman with a Mini-Mental State Examination (MMSE) score of 11/30. She experienced seeing a stranger, children, and cats at home, which frightened her. VH frequently occurred in the living room and bedroom. The PA-LE showed that several environmental features, such as cushions on a sofa, the pattern on a carpet under a table, and clothing on hangers, were suggestive triggers of VH. Patient 2 was an 88-year-old woman with a MMSE score of 5/30. She had seen strangers, children, and animals at home, some of which were linked to a theft delusion. VH frequently occurred in the living room and bedroom. The PA-LE found that several environmental features, such as clothing on hangers and dolls, were suggestive of VH triggers. Non-pharmacological approaches were tailored to the patients' environmental and psychological states using interviews and PA-LE. This included removing environmental triggers, reducing negative mood, and providing coping strategies for VH. This improved their VH and their caregivers' knowledge of VH.

Conclusion

Phenomenological assessments using photographs of the patient's home could identify the environmental triggers associated with VH in patients with DLB and assist in environmental adjustments.

Investigation of the Approaches to Optimal Exercise Interventions Based on Dementia Type: A Theoretical Review

The aim of this study is to enhance comprehension of the different types and features of dementia, including their symptoms, diagnosis and medical treatment, and to propose various evidence-based exercise interventions and their clinical applications tailored to each specific type of dementia. The theoretical review includes the analysis of publications in the scientific databases PubMed/Medline, Ebsco, Scielo, and Google. A total of 177 articles were found, of which 84 were studied in depth. With the prevalence of all forms of dementia projected to increase from 57.4 million in 2019 to 152.8 million in 2050, personalized treatment strategies are needed. This review discusses various forms of dementia, including their pathologies, diagnostic criteria, and prevalence rates. The importance of accurate diagnosis and tailored care is emphasized, as well as the effectiveness of physical exercise in improving cognitive function in dementia patients. For Alzheimer's, a combination of drug therapies and exercises is recommended to enhance cerebral blood flow and neurotransmitter activity. To improve cognitive and motor functions in Lewy body dementia, a combination of pharmacological and physical therapies is recommended. For managing frontotemporal dementia, a mix of medication and exercises aimed at emotion regulation, including aerobic exercises, and a unified protocol, is suggested. For mild cognitive impairment, aerobic and functional exercises are important in delaying cognitive decline and enhancing cognitive performance. In conclusion, individualized care and treatment plans tailored to the specific characteristics of each disease type can improve the quality of life for individuals with this condition and effectively manage this growing global health issue.

Developing an ontology of non-pharmacological treatment for emotional and mood disturbances in dementia

Emotional and mood disturbances are common in people with dementia. Non-pharmacological interventions are beneficial for managing these disturbances. However, effectively applying these interventions, particularly in the person-centred approach, is a complex and knowledge-intensive task. Healthcare professionals need the assistance of tools to obtain all relevant information that is often buried in a vast amount of clinical data to form a holistic understanding of the person for successfully applying non-pharmacological interventions. A machine-readable knowledge model, e.g., ontology, can codify the research evidence to underpin these tools. For the first time, this study aims to develop an ontology entitled Dementia-Related Emotional And Mood Disturbance Non-Pharmacological Treatment Ontology (DREAMDNPTO). DREAMDNPTO consists of 1258 unique classes (concepts) and 70 object properties that represent relationships between these classes. It meets the requirements and quality standards for biomedical ontology. As DREAMDNPTO provides a computerisable semantic representation of knowledge specific to non-pharmacological treatment for emotional and mood disturbances in dementia, it will facilitate the application of machine learning to this particular and important health domain of emotional and mood disturbance management for people with dementia.

The high cost of care and limited evidence on cost-effective strategies for Lewy body dementia: systematic review of evidence

BACKGROUND

Lewy body dementia (LBD) is a prevalent yet frequently underdiagnosed form of dementia, accounting for up to 15% of all dementia cases.

AIMS

This study aims to increase awareness and advocacy for LBD by gathering and critically assessing the economic evidence, including the cost of illness and cost-effectiveness of interventions for managing LBD.

METHOD

A systematic literature review was undertaken with EMBASE, Medline, CINAHL, PsycINFO, NHS Economic Evaluation Database and EconLit. This search was supplemented by grey literature on Google Scholar and reviewing the reference lists of identified studies. The papers included in the review were published between 2008 and 2023, and involved participants with LBD (dementia with Lewy bodies or Parkinson's disease dementia), which either addressed the cost of illness or conducted an economic evaluation.

RESULTS

Thirteen papers were included, comprising ten cost-of-illness studies and three economic evaluations. The cost of LBD tends to be higher than that of other forms of dementia, such as Alzheimer's disease, and these costs escalate more steeply as the disease progresses. These cost differences may not be solely influenced by the subtype of dementia, but possibly also by patient characteristics like physical and cognitive abilities. Cost-effectiveness of potential interventions for LBD is limited.

CONCLUSIONS

Despite numerous drug trials and other interventions for dementia, very few have targeted LBD, let alone explored the cost-effectiveness of such therapies for LBD. This disparity highlights the urgent need for cost-effective strategies and interventions targeting LBD. We propose the establishment of universally accepted standards for LBD research.

Physical exercise and its effects on people with Parkinson's disease: Umbrella review

INTRODUCTION

Parkinson's disease is neurodegenerative, complex and progressive, manifesting in a slow and irreversible way. Physical exercise has been proposed as therapeutic alternative to people with Parkinson´s disease.

OBJECTIVE

To synthesize knowledge about the effects of physical exercise on people with Parkinson´s Disease as presented by published systematic reviews.

METHODS

Nine electronic databases and two grey literature databases were searched for systematic reviews reporting the effects of physical exercises on people with Parkinson´s Disease. Searches involved a two-phase process, by, at least, two independent reviewers. Methodological quality of the included systematic reviews was assessed using AMSTAR-2.

RESULTS

From 2,122 systematic reviews, 139 were included. Motor outcomes were assessed in 91% of the studies, with balance being the most studied. Non-motor outcomes were assessed in 68% of the studies, with emphasis on quality of life. Physical exercises were classified into five categories: aerobic exercises, strength, combined, sensorimotor activities and other activity protocols. Findings of the systematic reviews suggest that all exercise categories can be prescribed to improve balance and mobility, while combined exercises, strength, and specific activities improve both motor and non-motor outcomes, and aerobic exercise and sensorimotor activities improve motor outcomes.

CONCLUSION

Current evidence from systematic reviews suggests that physical exercises impacts both motor and non-motor outcomes in people with Parkinson´s Disease. Limits in evidence provided by the systematic reviews were related to methodological issues and to the description of the interventions and must be considered to improve decision-making and clinical application.

Systematic review of pharmacological interventions for people with Lewy body dementia

OBJECTIVE

Lewy body dementia (LBD) is the second most common neurodegenerative dementia, and it causes earlier mortality and more morbidity than Alzheimer's disease. Reviewing current evidence on its pharmacological management is essential for developing evidence-based clinical guidelines, and for improving the quality of its clinical care. Hence, we systematically reviewed all studies that investigated the efficacy of any medication for managing various symptoms of LBD.

METHOD

We identified eligible studies by searching 15 databases comprehensively. We completed quality assessment, extracted relevant data, and performed GRADE assessment of available evidence. We conducted meta-analyses when appropriate (PROSPERO:CRD42020182166).

RESULTS

We screened 18,884 papers and included 135 studies. Our meta-analyses confirmed level-1 evidence for Donepezil's efficacy of managing cognitive symptoms of dementia with Lewy bodies (DLB) (SMD = 0.63; p < 0.001) and Parkinson's Disease Dementia (PDD) (SMD = 0.43; p < 0.01), and managing hallucinations in DLB (SMD=-0.52; p = 0.02). Rivastigmine and Memantine have level-2 evidence for managing cognitive and neuropsychiatric symptoms of DLB. Olanzapine and Yokukansan have similar evidence for managing DLB neuropsychiatric symptoms. Level-2 evidence support the efficacy of Rivastigmine and Galantamine for managing cognitive and neuropsychiatric symptoms of PDD.

CONCLUSION

We list evidence-based recommendations for the pharmacological management of DLB and PDD, and propose specific clinical guidelines for improving their clinical management.

Supplemental data for this article can be accessed online at https://doi.org/10.1080/13607863.2022.2032601 .

One Minute of EEG Data Provides Sufficient and Reliable Data for Identifying Lewy Body Dementia

OBJECTIVE

To determine the minimum duration of electroencephalography (EEG) data necessary to differentiate EEG features of Lewy body dementia (LBD), that is, dementia with Lewy bodies and Parkinson disease dementia, from non-LBD patients, that is, Alzheimer disease and Parkinson disease.

METHODS

We performed quantitative EEG analysis for 16 LBD and 14 non-LBD patients. After artifact removal, a fast Fourier transform was performed on 90, 60, and thirty 2-second epochs to derive dominant frequency; dominant frequency variability; and dominant frequency prevalence.

RESULTS

In LBD patients, there were no significant differences in EEG features derived from 90, 60, and thirty 2-second epochs (all P >0.05). There were no significant differences in EEG features derived from 3 different groups of thirty 2-second epochs (all P >0.05). When analyzing EEG features derived from ninety 2-second epochs, we found that LBD had significantly reduced dominant frequency, reduced dominant frequency variability, and reduced dominant frequency prevalence alpha compared with the non-LBD group (all P <0.05). These same differences were observed between the LBD and non-LBD groups when analyzing thirty 2-second epochs.

CONCLUSIONS

There were no differences in EEG features derived from 1 minute versus 3 minutes of EEG data, and both durations of EEG data equally differentiated LBD from non-LBD.

Towards an understanding of the pathological basis of senile depression and incident dementia: Implications for treatment

Senile depression (SD) is a heterogeneous syndrome. Several clinical profiles are more likely to appear in SD than in early-life depression, but it remains unclear whether the pathophysiology is different. The prevalence of dementia increases with aging, and the underlying pathophysiological processes in the preclinical phase begin even before cognitive deficits or neurological signs appear. SD may be either a risk factor for developing dementia or a prodromal stage of dementia. The inconsistent findings regarding the association between SD and incident dementia may be attributable to the neuropathological heterogeneity underlying SD. Most studies have focused on patients with the clinical diagnosis of Alzheimer disease (AD) as an outcome, but several clinicopathological studies suggest that primary age-related tauopathy and argyrophilic grain disease may account for a proportion of cases clinically misdiagnosed as AD in the elderly population. Furthermore, most AD cases have additional neuropathologic changes such as cerebrovascular disease and Lewy body disease. Here, we review the neuropathological findings linking SD to incident dementia, focusing on common age-related neuropathologies. In particular, the roles of disturbance of neural circuity, imbalance of monoaminergic systems, dysregulation of the hypothalamic-pituitary-adrenal axis, and elevated neuroinflammatory status are discussed. Finally, we review the current treatment of SD in the context of age-related neuropathological changes.

Electroconvulsive therapy improves psychotic symptoms in patients with dementia with Lewy bodies

PURPOSE

The aim of this study was to examine the efficacy and safety of electroconvulsive therapy (ECT) for psychotic symptoms of dementia with Lewy bodies (DLB), and also to determine its use as an adaptive criterion.

METHODS

Eight patients aged 66-83 years old (mean 75.4 ± 5.9 years) diagnosed with probable DLB based on the criteria for DLB and who received ECT between September 2013 and December 2019 at Aichi Medical University were enrolled. The efficacy and safety of ECT were retrospectively examined. Psychotic symptoms were evaluated using the Brief Psychiatric Rating Scale (BPRS), while parkinsonism was evaluated based on Hoehn-Yahr (HY) stage, with both scores analyzed and compared statistically between before and after ECT. Additionally, a follow-up survey after undergoing ECT was performed.

RESULTS

Two incidents occurred during ECT sessions, arrhythmia in one patient and respiratory arrest in another, both of whom quickly recovered. Following ECT, a significant improvement in BPRS score was noted (p < 0.018, Wilcoxon signed rank test), whereas no significant difference was seen in regard to HY stage (p = 0.059). Follow-up survey findings obtained after ECT (mean observation period 15.9 ± 16.7 months), showed that all eight patients were alive and none had a relapse of psychotic symptoms.

CONCLUSION

The present results suggest that ECT for patients with mild to moderate DLB and drug therapy-resistant psychotic symptoms is safe, well tolerated and effective. We consider it worth considering as a DLB therapeutic option.

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.

Treatment of dementia: recommendations of the Scientific Department of Cognitive Neurology and Aging of the Brazilian Academy of Neurology

ABSTRACT There is currently no cure for neurodegenerative or vascular dementias, but some pharmacological and non-pharmacological interventions may contribute to alleviate symptoms, slow disease progression and improve quality of life. Current treatment approaches are based on etiology, symptom profile and stage of dementia. This manuscript presents recommendations on pharmacological and non-pharmacological treatments of dementia due to Alzheimer’s disease, vascular cognitive impairment, frontotemporal dementia, Parkinson’s disease dementia, and dementia with Lewy bodies.

Tratamento da demência: recomendações do Departamento Científico de Neurologia Cognitiva e do Envelhecimento da Academia Brasileira de Neurologia

RESUMO Atualmente não há tratamento curativo para as demências neurodegenerativas ou para a demência vascular, mas algumas intervenções farmacológicas e não farmacológicas podem contribuir para aliviar os sintomas, retardar a progressão da doença e melhorar a qualidade de vida. As abordagens terapêuticas atuais são baseadas na etiologia, no perfil dos sintomas e no estágio da demência. Neste artigo apresentamos recomendações sobre os tratamentos farmacológicos e não farmacológicos da demência devida à doença de Alzheimer, comprometimento cognitivo vascular, demência frontotemporal, demência da doença de Parkinson e demência com corpos de Lewy.

Promoting independence in Lewy body dementia through exercise: the PRIDE study

Background

Lewy body dementia (LBD) is an aggressive type of dementia of rapid, fluctuating disease trajectory, higher incidence of adverse events, and poorer functional independence than observed in Alzheimer’s disease dementia. Non-pharmacological treatments such as progressive, high-intensity exercise are effective in other neurological cohorts but have been scarcely evaluated in LBD.

Methods

The Promoting Independence in Lewy Body Dementia through Exercise (PRIDE) trial was a non-randomised, non-blinded, crossover pilot trial involving older adults with LBD consisting of a baseline assessment, an 8-week wait-list, and an 8-week exercise intervention. The aims of this study were to evaluate the determinants of the primary outcome functional independence, as measured by the Movement Disorder Society Unified Parkinson’s Disease Rating Scale, and the feasibility and preliminary efficacy of an exercise intervention on this outcome. Additionally, important clinical characteristics were evaluated to explore associations and treatment targets. The exercise intervention was supervised, clinic-based, high-intensity progressive resistance training (PRT), challenging balance, and functional exercises, 3 days/week.

Results

Nine participants completed the baseline cross-sectional study, of which five had a diagnosis of Parkinson’s disease dementia (PDD), and four dementia with Lewy Bodies (DLB). Six completed the exercise intervention (three PDD, three DLB). The cohort was diverse, ranging from mild to severe dementia and living in various residential settings. Greater functional independence at baseline was significantly associated with better physical function, balance, cognition, quality of life, muscle mass ratio, walking endurance, faster walking speed and cadence, and lower dementia severity (p < 0.05). Participants declined by clinically meaningful amounts in functional independence, cognition, physical function, muscle mass, and weight over the wait-list period (p < 0.05). Following exercise, participants improved by clinically meaningful amounts in functional independence, cognition, physical function, and strength (p < 0.05). Progressive, high intensity exercise was well-tolerated (> 80% adherence), and only one minor exercise-related adverse event occurred.

Conclusions

PRIDE is the first exercise trial conducted specifically within individuals diagnosed with LBD, and provides important insight for the design of larger, randomized trials for further evaluation of progressive, high-intensity exercise as a valuable treatment in LBD.

Trial registration

The PRIDE trial protocol has previously been prospectively registered (08/04/2016, ANZCTR: ACTRN12616000466448).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03347-2.

Recent advances in Lewy body dementia: A comprehensive review

Lewy Body Dementia is the second most frequent neurodegenerative illness proven to cause dementia, after Alzheimer's disease (AD). It is believed to be vastly underdiagnosed, as there is a significant disparity between the number of cases diagnosed clinically and those diagnosed via neuropathology at the time of postmortem autopsy. Strikingly, many of the pharmacologic treatments used to treat behavioral and cognitive symptoms in other forms of dementia exacerbate the symptoms of DLB. Therefore, it is critical to accurately diagnose DLB as these patients require a specific treatment approach. This article focuses on its pathophysiology, risk factors, differentials, and its diverse treatment modalities. In this study, an English language literature search was conducted on Medline, Cochrane, Embase, and Google Scholar till April 2022. The following search strings and Medical Subject Headings (MeSH) terms were used: "Lewy Body Dementia," "Dementia with Lewy bodies," and "Parkinson's Disease Dementia." We explored the literature on Lewy Body Dementia for its epidemiology, pathophysiology, the role of various genes and how they bring about the disease, biomarkers, its differential diagnoses and treatment options.

Ultrabrief Right Unilateral Electroconvulsive Therapy for the Treatment of the Neuropsychiatric Symptoms of Dementia with Lewy Bodies

OBJECTIVES

Dementia with Lewy bodies (DLB) is a debilitating disorder associated with a number of distressing neuropsychiatric symptoms. There is currently limited guidance regarding the most effective strategies of managing these symptoms, and both pharmacologic and nonpharmacologic strategies are often used. Electroconvulsive therapy (ECT) has been reported as a potential nonpharmacologic method to alleviate some of these debilitating neuropsychiatric symptoms. However, there remains a paucity of evidence in current literature. This report aims to add to existing literature regarding ECT in DLB by highlighting successful treatment in seven cases.

METHODS

Our study is a retrospective case series of 7 patients with DLB who received treatment with ultrabrief (UB) right unilateral (RUL) ECT for the treatment of agitation and depressive symptoms. Participants included patients with a diagnosis of DLB who were admitted to Emory University Hospital at Wesley Woods from 2011 to 2020 presenting with agitation and/or depressive symptoms after failing pharmacologic intervention. Patients underwent UB RUL ECT administered by a board-certified psychiatrist. After treatment, Pittsburg Agitation Scale and Clinical Global Impression-Improvement scales were recorded as measures of agitation and clinical improvement, respectively.

RESULTS

All 7 patients responded to UB RUL ECT with marked improvement in their presenting symptoms of agitation and/or depression without significant adverse effects from treatment.

CONCLUSIONS

Ultrabrief RUL ECT seems to be a safe and effective treatment of the agitative and depressive features of DLB.

Using a Non-Wearable Actigraphy in Nursing Care for Dementia With Lewy Bodies

People who have dementia with Lewy bodies often have sleep disorders. We used non-wearable devices to record and categorize the sleep patterns of patients with Lewy body dementia. Individual sleep data at a dementia-care unit in Japan were recorded using non-wearables. One week's worth of data from 18 patients was analyzed. Median metrics for all participants were the following: sleep efficiency, 68% (23-89); sleep duration at night, 6.8 hours (1.6-11.1); times getting out of bed at night, 3.5 (0-13). We identified three types of abnormal sleep: extremely short sleep duration, excessive sleep duration at night, and excessive number of times getting out of bed at night. Sleep disturbances in Lewy body dementia patients are treated using various practices; staff must choose the most effective plan for each patient's situation. Monitoring patient sleep using non-wearable provides more objective data that can help staff better personalize nursing care.

Improving the diagnosis and management of Lewy body dementia: the DIAMOND-Lewy research programme including pilot cluster RCT

Background

Lewy body dementia, comprising both dementia with Lewy bodies and Parkinson’s disease dementia, is the second commonest cause of neurodegenerative dementia. Existing evidence suggests that it is underdiagnosed and without a consistent approach to management.

Objectives

To improve the diagnosis and management of Lewy body dementia by (1) understanding current diagnostic practice for dementia with Lewy bodies and Parkinson’s disease dementia; (2) identifying barriers to and facilitators of diagnosis and management; (3) developing evidence-based assessment toolkits to improve diagnosis of dementia with Lewy bodies and Parkinson’s disease dementia; (4) producing a management toolkit to facilitate management; and (5) undertaking a pilot cluster randomised clinical trial.

Design

Work package 1 assessed clinical diagnostic rates from case notes for dementia with Lewy bodies and Parkinson’s disease dementia before and after (work package 1 repeated) introduction of an assessment toolkit. In work package 2, we developed a management toolkit for Lewy body dementia. In work package 3, we developed assessment toolkits for dementia with Lewy bodies and Parkinson’s disease dementia and piloted these and the management toolkit in a clinical service. In work package 4, we undertook a pilot study of 23 services in nine NHS trusts that were cluster randomised to receiving and using the management toolkit or standard care. Work package 5 comprised a series of qualitative studies, examining barriers to and facilitators of diagnosis and management.

Setting

Secondary care memory assessment and movement disorder services in England.

Interventions

Assessment toolkits for Lewy body dementia consisted of questions for diagnostic symptoms, and management toolkits comprised 161 guidance statements grouped under five symptom domains.

Review methods

The systematic reviews of pharmacological and non-pharmacological management were based on published literature, with meta-analysis when possible, following a search of several electronic databases and the grey literature using terms related to Lewy body dementia, without restriction on time or language.

Participants

Participants aged ≥ 50 years diagnosed with dementia with Lewy bodies or Parkinson’s disease dementia and, for work package 1 and work package 1 repeated, non-dementia with Lewy bodies and non-Parkinson’s disease dementia controls. The qualitative studies included people with Lewy body dementia, carers and professionals.

Main outcome measures

For work packages 1 and 1 repeated, diagnostic rates for dementia with Lewy bodies and Parkinson’s disease dementia as a proportion of all dementia or Parkinson’s disease. For work packages 2 and 3, the production of diagnostic and management toolkits. For work package 4, feasibility of undertaking a cluster randomised trial of the toolkits, measured by number of participants recruited and use of the toolkits, assessed qualitatively.

Results

Work package 1 – 4.6% of dementia cases in secondary care received a dementia with Lewy bodies diagnosis (with significant differences in diagnostic rates between services) and 9.7% of those with Parkinson’s disease had a diagnosis of Parkinson’s disease dementia. There was evidence of delays in diagnosis for both dementia with Lewy bodies and Parkinson’s disease dementia compared with control patients, and the costs of dementia with Lewy bodies and Parkinson’s disease dementia were also greater than those for matched controls (p < 0.01 for both). Work package 2 – we produced 252 statements regarding Lewy body dementia management and, following a Delphi process, 161 statements were included in a management toolkit. Work package 3 – piloting indicated that separate assessment toolkits for use in memory clinic and movement disorder services were preferred, but a single toolkit for Lewy body dementia management was suitable. Work package 4 – we were able to recruit Lewy body dementia patients to target and recruited 131 patients within 6 months (target n = 120), of whom > 80% were retained in the study at 6 months. Work package 5 – barriers to diagnosis and management of Lewy body dementia were complex. Managing Lewy body dementia often requires input from a range of specialties and, therefore, care pathways may be fragmented. Positive attitudes to diagnosing Lewy body dementia, working with a team with expertise in Lewy body dementia and opportunities for cross-specialty discussion of patients with complex needs facilitated diagnosis and management. The toolkits were generally well received, particularly the management toolkit. Implementation, however, varied, reflecting differences in attitudes, skills, time and local leadership. Work package 1 repeated – following introduction of the assessment toolkit, we found that 9.7% of dementia cases had dementia with Lewy bodies (a significant increase from baseline; p = 0.0019), but Parkinson’s disease dementia rates were similar (8.2%) to baseline.

Limitations

We included only two geographical regions and evidence informing the management toolkit was limited. Work package 4 was a pilot study and, therefore, we did not set out to assess the extent to which use of the management toolkit altered outcomes at the individual patient level. We noted implementation of the toolkits was variable. The increase in diagnostic rates in dementia with Lewy bodies following introduction of the assessment toolkits cannot be necessarily causally attributed to them.

Conclusions

Dementia with Lewy bodies and Parkinson’s disease dementia were diagnosed in secondary care NHS services, with a lower frequency (around half) than that expected from known prevalence rates. The introduction of assessment toolkits for dementia with Lewy bodies and Parkinson’s disease dementia was associated with increased diagnostic rates of dementia with Lewy bodies, but not Parkinson’s disease dementia. Qualitative studies indicated inherent complexities of the disease itself, with treatment requiring input from different specialties and the potential for fragmented services, a workforce with variable training and confidence in Lewy body dementia, and negative attitudes towards diagnosis. The cluster randomised pilot trial demonstrated that patients could be successfully recruited, and provided preliminary evidence that the toolkits could be implemented in clinical services.

Future work

The evidence base informing the management of Lewy body dementia is limited, especially for non-pharmacological interventions. More well-designed randomised controlled trials for both cognitive and non-cognitive symptoms are needed.

Trial registration

Current Controlled Trials ISRCTN11083027.

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 9, No. 7. See the NIHR Journals Library website for further project information.

The feasibility and acceptability of a psychosocial intervention to support people with dementia with Lewy bodies and family care partners

Objectives

Psychosocial support for people with dementia with Lewy bodies (DLB) and family care partners is frequently lacking, despite the need expressed by those with lived experience. Our objective was to examine the feasibility and acceptability of an intervention designed to build coping capability.

Design

The design was non-randomised with all participants receiving the intervention.

Setting

The setting was a Memory Assessment and Management Service in the Northeast of England.

Participants

Participants comprised 19 dyads consisting of a person with DLB and a family care partner.

Intervention

The intervention was group-based, with weekly sessions attended for up to four successive weeks. It was informed by Social Cognitive Theory.

Measurements

Data were collected on recruitment, attendance and attrition, self-efficacy, mood, stress and participant experience.

Results

Recruitment was achieved with minimal attrition and three successive groups were delivered. Care partners felt more in control and able to cope in at least 3 of 13 areas with 73% feeling this way in eight or more areas. Three themes were identified from post-intervention interviews: people like us, outcomes from being a group member and intervention design.

Conclusions

A DLB-specific group intervention is acceptable to people with DLB and family care partners, and recruitment is feasible within a specialist service. Participation may enhance understanding of this condition and reduce social isolation. It may improve care partners’ coping capability particularly if targeted towards those with low prior understanding of DLB and more stress. Means of evaluating outcomes for people with DLB need further development.

Exploring the experiences of living with Lewy body dementia: An integrative review

AIM

Lewy body dementia is a common neurodegenerative dementia with unique challenges in managing day-to-day life. A more in-depth multifaceted picture of the Lewy body dementia lived experience will enable identification of best practice and future research direction. The review aim was to explore experiences of people living with Lewy body dementia and their family carers.

DESIGN

Integrative review method informed by Whittemore and Knafl, supported by the information retrieval framework PALETTE. A convergent integrated approach enabled synthesis of key findings and theme identification.

DATA SOURCES

Medline, CINAHL, PsycINFO, AMED, and ALOIS databases were systematically searched to find studies published between 1995 and 2020.

REVIEW METHODS

Twenty-six articles from twenty studies were synthesized (from 1583 retrieved). Quality and relevance were appraised using the Mixed-Methods Appraisal Tool and Gough's 'Weight of Evidence' framework. Data management was supported by ATLAS.ti 8 and COVIDENCE software.

RESULTS

Four themes were identified: living with an uncertain diagnosis and prognosis; fear of the now - worry for the future; living with behavioural and psychiatric symptoms; and maintaining a social and emotional life. People reported difficulty finding information and support around diagnosis, disease progression and managing complex symptoms. The result is increased caregiver burden, grief and stress and reduced quality of life.

CONCLUSION

Delayed diagnosis and complex symptom burden means people are not getting the timely support and information they need to live and die well. Current evidence is largely quantitative, with a focus on family caregiver burden and unmet need. The challenge remains in how to capture a more holistic picture of the lived experience for people living with Lewy body dementia and those who care for them.

IMPACT

This review highlighted current knowledge and identified gaps in exploring the lived experience for people with Lewy body dementia and their families.

Immediate effects of treadmill walking in individuals with Lewy body dementia and Huntington's disease

BACKGROUND

Treadmill training may improve gait disorders associated with neurodegenerative diseases. In Parkinson's disease (PD), treadmill training alters gait patterns after one session, and long-term training improves gait parameters, fall risk, and quality of life.

RESEARCH QUESTION

What is the feasibility and safety of using this intervention for people with Lewy body dementia (LBD) or Huntington's disease (HD)?

METHODS

In this observational study, 10 individuals with HD, 8 individuals with LBD, and 10 control individuals walked for 20 min on a treadmill using a speed dependent protocol starting at a slow comfortable speed and increasing incrementally toward their normal overground speed. Feasibility was determined by compliance to protocol and safety by no incidents of abnormal vital signs or expressions of distress. Changes in gait measures, Timed Up and Go (TUG) scores and quantitative motor function measures (Q-Motor; precision grasp force variability, finger and foot tapping frequency) before and after treadmill walking were analyzed using linear models.

RESULTS

Treadmill training is feasible and safe in LBD and HD; although, participants could not initiate treadmill walking at their comfortable overground speeds, and only 3 participants with HD were able to achieve their overground walking speed within the 20-minute session. No changes in gait measures, TUG times, and Q-Motor measures were found among LBD and HD participants after treadmill walking, although control participants demonstrated significant increases in several gait measures, and foot tap frequency (estimated difference = 0.290; p = 0.026).

SIGNIFICANCE

Longer and more frequent treadmill sessions may be needed to see gait and motor function effects in LBD and HD. Motor and cognitive impairments associated with these diseases may make them less amenable to the effects of treadmill training.

Characterization of symptoms and determinants of disease burden in dementia with Lewy bodies: DEvELOP design and baseline results

BACKGROUND

The DEmEntia with LEwy bOdies Project (DEvELOP) aims to phenotype patients with dementia with Lewy bodies (DLB) and study the symptoms and biomarkers over time. Here, we describe the design and baseline results of DEvELOP. We investigated the associations between core and suggestive DLB symptoms and different aspects of disease burden, i.e., instrumental activities of daily living (IADL) functioning, quality of life (QoL), and caregiver burden.

METHODS

We included 100 DLB patients (69 ± 6 years, 10%F, MMSE 25 ± 3) in the prospective DEvELOP cohort. Patients underwent extensive assessment including MRI, EEG/MEG, ¹²³FP-CIT SPECT, and CSF and blood collection, with annual follow-up. Core (hallucinations, parkinsonism, fluctuations, RBD) and suggestive (autonomous dysfunction, neuropsychiatric symptoms) symptoms were assessed using standardized questionnaires. We used multivariate regression analyses, adjusted for age, sex, and MMSE, to evaluate how symptoms related to the Functional Activities Questionnaire, QoL-AD questionnaire, and Zarit Caregiver Burden Interview.

RESULTS

In our cohort, RBD was the most frequently reported core feature (75%), while visual hallucinations were least frequently reported (39%) and caused minimal distress. Suggestive clinical features were commonly present, of which orthostatic hypotension was most frequently reported (64%). Ninety-five percent of patients showed EEG/MEG abnormalities, 88% of ¹²³FP-CIT SPECT scans were abnormal, and 53% had a CSF Alzheimer's disease profile. Presence of fluctuations, lower MMSE, parkinsonism, and apathy were associated with higher IADL dependency. Depression, constipation, and lower IADL were associated with lower QoL-AD. Apathy and higher IADL dependency predisposed for higher caregiver burden.

CONCLUSION

Baseline data of our prospective DLB cohort show clinically relevant associations between symptomatology and disease burden. Cognitive and motor symptoms are related to IADL functioning, while negative neuropsychiatric symptoms and functional dependency are important determinants of QoL and caregiver burden. Follow-up is currently ongoing to address specific gaps in DLB research.

Development of Neuroleptic Malignant Syndrome in a Patient with Lewy Body Dementia after Intramuscular Administration of Paliperidone

Neuroleptic malignant syndrome (NMS) is a potentially fatal diagnosis composed of hyperpyrexia, muscle rigidity, altered mental status, and autonomic instability. This syndrome has significant systemic complications including acute renal failure, rhabdomyolysis, hyperkalemia, and seizure. It is associated with the use of both typical and atypical antipsychotics. Due to the extensive neurodegenerative destruction of dopaminergic and acetylcholinergic pathways, patients with Lewy body dementia (LBD) are particularly sensitive to antidopaminergic and anticholinergic medications, making them more susceptible to extrapyramidal side effects and NMS. We present a case of a 72-year-old female with LBD who developed muscular rigidity, vital sign instability, and altered mental status after receiving one dose of paliperidone palmitate injection two weeks prior to admission. Initial blood work was unrevealing. Extensive workup including EEG, lumbar puncture with cerebrospinal fluid analysis, and brain MRI was unremarkable. She was treated with seven days of bromocriptine and a lorazepam taper with improvement in muscle rigidity. However, her mental status never improved, and she remained comatose. She was later intubated for airway protection after an aspiration event that led to hypoxia. Her respiratory status never recovered, and she was transitioned to comfort care. This case demonstrates the complexity and potential fatality of NMS. Clinicians should be aware of this dangerous complication of antipsychotic use in patients with LBD as these patients may be more susceptible to this complication.

Pharmacological management of dementia with Lewy bodies with a focus on zonisamide for treating parkinsonism

INTRODUCTION

Dementia with Lewy bodies (DLB) has no approved symptomatic or disease-modifying treatments in the US and Europe, despite being the second most common cause of neurodegenerative dementia.

AREAS COVERED

Herein, the authors briefly review the DLB drug development pipeline, providing a summary of the current pharmacological intervention studies. They then focus on the anticonvulsant zonisamide, a benzisoxazole derivative with a sulfonamide group and look at its value for treating parkinsonism in DLB.

EXPERT OPINION

Several new compounds are being tested in DLB, the most innovative being those aimed at decreasing brain accumulation of α-synuclein. Unfortunately, new drug testing is challenging in terms of consistent diagnostic criteria and lack of reliable biomarkers. Few randomized controlled trials (RCTs) are well-designed, with enough power to detect significant drug effects. Levodopa monotherapy can treat the parkinsonism in DLB, but it can cause agitation or visual hallucination worsening. Two Phase II/III RCTs of DLB patients recently reported a statistically significant improvement in motor function in those receiving zonisamide as an adjunctive treatment to levodopa. New biomarker strategies and validated outcome measures for DLB or prodromal DLB may enhance clinical trial design for the development of specific disease-modifying treatments.

Epigenetic regulation in the pathophysiology of Lewy body dementia

Lewy body dementia encompasses both dementia with Lewy bodies and Parkinson's disease dementia. Although both are common causes of dementia, they remain relatively understudied. The review summarises the clinico-pathologic characteristics of Lewy Body dementia and discusses the genetic and environmental evidence contributing to the risk of developing the condition. Considering that the pathophysiology of Lewy body dementia is not yet fully understood, here we focus on the role of epigenetic mechanisms as potential key mediators of gene-environment interactions in the development of the disease. We examine available important data on genomics, epigenomics, gene expression and proteomic studies in Lewy body dementia on human post-mortem brain and peripheral tissues. Genetic variation and epigenetic modifications in key genes involved in the disorder, such as apolipoprotein E (APOE), α-synuclein (SNCA) and glucocerobrosidase (GBA), suggest a central involvement of epigenetics in DLB but conclusive evidence is scarce. This is due to limitations of existing literature, such as small sample sizes, lack of replication and lack of studies interrogating cell-type specific epigenetic modifications in the brain. Future research in the field can improve the understanding of this common but complex and rapidly progressing type of dementia and potentially open early diagnostic and effective therapeutic targets.

New evidence on the management of Lewy body dementia

Dementia with Lewy bodies and Parkinson's disease dementia, jointly known as Lewy body dementia, are common neurodegenerative conditions. Patients with Lewy body dementia present with a wide range of cognitive, neuropsychiatric, sleep, motor, and autonomic symptoms. Presentation varies between patients and can vary over time within an individual. Treatments can address one symptom but worsen another, which makes disease management difficult. Symptoms are often managed in isolation and by different specialists, which makes high-quality care difficult to accomplish. Clinical trials and meta-analyses now provide an evidence base for the treatment of cognitive, neuropsychiatric, and motor symptoms in patients with Lewy body dementia. Furthermore, consensus opinion from experts supports the application of treatments for related conditions, such as Parkinson's disease, for the management of common symptoms (eg, autonomic dysfunction) in patients with Lewy body dementia. However, evidence gaps remain and future clinical trials need to focus on the treatment of symptoms specific to patients with Lewy body dementia.

Psychological Interventions for People with Huntington's Disease: A Call to Arms

BACKGROUND

Although Huntington's disease (HD) can cause a wide range of psychological difficulties, no review has ever been carried out on the range of psychological interventions adopted with this population.

OBJECTIVE

To scope the literature on psychological interventions for psychological difficulties in people affected by HD.

METHODS

A systematic scoping review was performed across MEDLINE, PsycINFO, CINAHL, Academic Search Ultimate, and Cochrane Library up to 1 March 2020.

RESULTS

From an initial return of 1579 citations, a total of nine papers were considered eligible for review. These included a qualitative investigation, three case studies, two case series, two uncontrolled pretest-posttest designs, and only one randomised control trial (RCT). Despite the wide range of psychological difficulties which can be experienced by people affected by the HD gene expansion, the adopted interventions only accounted for five main psychological outcomes (anxiety, apathy, depression, irritability, and coping). Further discussion and suggestions for future research are provided for each outcome.

CONCLUSION

The current literature on psychological interventions in people affected by HD is extremely limited both in terms of methods and addressed clinical outcomes. Consequently, no conclusions can be offered yet as to which psychological therapy may help this population. As further more comprehensive research is urgently needed for this group, the ultimate aim of the present review is to act as a call to arms for HD researchers worldwide to help shed light on the most effective way to translate psychological theory into practice for the benefit of people affected by HD.

A Review of Dementia with Lewy Bodies' Impact, Diagnostic Criteria and Treatment

Dementia with Lewy bodies is one of the most common causes of dementia. It is not as common as Alzheimer's disease; the general public's awareness of the disease is poor in comparison. Its effects on caregivers and patients alike are not well known to the general population. There are currently no FDA-approved medications specifically for the treatment of DLB. Many of the medications that are approved for Alzheimer's disease are widely used in the treatment of DLB with varying degrees of success. Treatment of DLB is life long and requires a dedicated team of physicians and caregivers to minimize the degree of morbidity and mortality experienced by the patients suffering from the disease as it progresses.

Are dementia with Lewy bodies and Parkinson's disease dementia the same disease?

BACKGROUND

Dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD), which share many clinical, neurochemical, and morphological features, have been incorporated into DSM-5 as two separate entities of major neurocognitive disorders with Lewy bodies. Despite clinical overlap, their diagnosis is based on an arbitrary distinction concerning the time of onset of motor and cognitive symptoms, namely as early cognitive impairment in DLB and later onset following that of motor symptoms in PDD. Their morphological hallmarks - cortical and subcortical α-synuclein/Lewy body plus β-amyloid and tau pathologies - are similar, but clinical differences at onset suggest some dissimilar profiles. Based on recent publications, including the fourth consensus report of the DLB Consortium, a critical overview is provided herein.

DISCUSSION

The clinical constellations of DLB and PDD include cognitive impairment, parkinsonism, visual hallucinations, and fluctuating attention. Intravitam PET and postmortem studies have revealed a more pronounced cortical atrophy, elevated cortical and limbic Lewy body pathologies, higher Aβ and tau loads in cortex and striatum in DLB compared to PDD, and earlier cognitive defects in DLB. Conversely, multitracer PET studies have shown no differences in cortical and striatal cholinergic and dopaminergic deficits. Clinical management of both DLB and PDD includes cholinesterase inhibitors and other pharmacologic and non-drug strategies, yet with only mild symptomatic effects. Currently, no disease-modifying therapies are available.

CONCLUSION

DLB and PDD are important dementia syndromes that overlap in many clinical features, genetics, neuropathology, and management. They are currently considered as subtypes of an α-synuclein-associated disease spectrum (Lewy body diseases), from incidental Lewy body disease and non-demented Parkinson's disease to PDD, DLB, and DLB with Alzheimer's disease at the most severe end. Cognitive impairment in these disorders is induced not only by α-synuclein-related neurodegeneration but by multiple regional pathological scores. Both DLB and PDD show heterogeneous pathology and neurochemistry, suggesting that they share important common underlying molecular pathogenesis with Alzheimer's disease and other proteinopathies. While we prefer to view DLB and PDD as extremes on a continuum, there remains a pressing need to more clearly differentiate these syndromes and to understand the synucleinopathy processes leading to either one.

Dementia with Lewy bodies and Parkinson's disease-dementia: current concepts and controversies

Dementia with Lewy bodies (DLB) and Parkinson's disease-dementia (PDD), although sharing many clinical, neurochemical and morphological features, according to DSM-5, are two entities of major neurocognitive disorders with Lewy bodies of unknown etiology. Despite considerable clinical overlap, their diagnosis is based on an arbitrary distinction between the time of onset of motor and cognitive symptoms: dementia often preceding parkinsonism in DLB and onset of cognitive impairment after onset of motor symptoms in PDD. Both are characterized morphologically by widespread cortical and subcortical α-synuclein/Lewy body plus β-amyloid and tau pathologies. Based on recent publications, including the fourth consensus report of the DLB Consortium, a critical overview is given. The clinical features of DLB and PDD include cognitive impairment, parkinsonism, visual hallucinations, and fluctuating attention. Intravitam PET and post-mortem studies revealed more pronounced cortical atrophy, elevated cortical and limbic Lewy pathologies (with APOE ε4), apart from higher prevalence of Alzheimer pathology in DLB than PDD. These changes may account for earlier onset and greater severity of cognitive defects in DLB, while multitracer PET studies showed no differences in cholinergic and dopaminergic deficits. DLB and PDD sharing genetic, neurochemical, and morphologic factors are likely to represent two subtypes of an α-synuclein-associated disease spectrum (Lewy body diseases), beginning with incidental Lewy body disease-PD-nondemented-PDD-DLB (no parkinsonism)-DLB with Alzheimer's disease (DLB-AD) at the most severe end, although DLB does not begin with PD/PDD and does not always progress to DLB-AD, while others consider them as the same disease. Both DLB and PDD show heterogeneous pathology and neurochemistry, suggesting that they share important common underlying molecular pathogenesis with AD and other proteinopathies. Cognitive impairment is not only induced by α-synuclein-caused neurodegeneration but by multiple regional pathological scores. Recent animal models and human post-mortem studies have provided important insights into the pathophysiology of DLB/PDD showing some differences, e.g., different spreading patterns of α-synuclein pathology, but the basic pathogenic mechanisms leading to the heterogeneity between both disorders deserve further elucidation. In view of the controversies about the nosology and pathogenesis of both syndromes, there remains a pressing need to differentiate them more clearly and to understand the processes leading these synucleinopathies to cause one disorder or the other. Clinical management of both disorders includes cholinesterase inhibitors, other pharmacologic and nonpharmacologic strategies, but these have only a mild symptomatic effect. Currently, no disease-modifying therapies are available.