New evidence on the management of Lewy body dementia

Electroconvulsive therapy ameliorates treatment-resistant depression in patient with Lewy body dementia

Lewy body dementia (LBD), the second most common degenerative dementia after Alzheimer's disease, is frequently associated with neuropsychiatric symptoms such as depression, anxiety, and apathy. These symptoms may precede cognitive decline, often resulting in misdiagnosis and inappropriate treatment. Electroconvulsive therapy (ECT) has emerged as a promising option for treatment-resistant depression in LBD. This report describes a 68-year-old female patient with LBD who received multiple ECT sessions for persistent severe depression and suicidal ideation. ECT led to marked symptom improvement across several hospitalizations. This case underscores the diagnostic and therapeutic challenges of neuropsychiatric symptoms in LBD and highlights ECT as a potential alternative when pharmacotherapy is inadequate. Early identification of LBD in patients with late-onset depression is essential to guide individualized treatment strategies.

Case Report: Lewy body dementia with unusual psychotic symptoms, atypically late parkinsonism, and patient sensitivity to first generation antipsychotics

Lewy body dementia is associated with abnormal eosinophilic A-synuclein neural inclusions (Lewy bodies) in the brain. It is a neurodegenerative illness-and the second most common type of dementia after Alzheimer's disease-that causes memory loss and severe problems in carrying out daily activities. In this report, we describe a case of Lewy body dementia that began with early psychotic symptoms with atypical features (transition from hallucinosis (hallucinatory insight) to true visual hallucinations) -without Parkinsonism. The patient exhibited sensitivity to first generation antipsychotic medication, which led to a worsening of her symptoms. Physicians should consider all possible diagnoses when confronted with atypical, early symptoms of visual hallucinosis or true hallucinations and dementia without Parkinsonism. Choosing antipsychotic medicines should be made with care given these patients' possible sensitivity to antipsychotics. The selection of antipsychotics should be consider among first, second and third generation options.

Tan I modulates astrocyte inflammatory responses through enhanced NAD+-Sirt1 pathway: Insights from metabolomics studies

Over the past decade, research has increasingly demonstrated that oligomeric α-synuclein (O-αS) plays a pivotal role in the pathogenesis of Parkinson's disease (PD), particularly in mediating dopaminergic neuron injury and neuroinflammation. In this study, we investigated the anti-inflammatory effects of tanshinone I (Tan I), an active component of the traditional Chinese medicine Danshen, on O-αS-induced inflammation in primary mouse astrocytes. Using metabolomics analysis, we identified key pathways regulated by Tan I. Our results showed that Tan I significantly suppressed O-αS-induced mRNA expression of pro-inflammatory cytokines, including interleukin-1β, IL-6, tumor necrosis factor-α and cyclooxygenase-2. Metabolomic profiling revealed that Tan I enhanced NAD+ metabolism, leading to activation of the NAD+-Sirt1 pathway and subsequent inhibition of nuclear factor-κB activity. Together, these findings suggest that Tan I attenuates neuroinflammatory response in astrocytes by modulating NAD+-dependent signaling mechanisms.

Awareness of national dementia guidelines and management of oldest-old and frail people living with dementia: a European survey of geriatricians

BACKGROUND

Management of dementia, particularly the use of pharmacological treatments, in the oldest old and those with frailty is complex because of the multiple types of dementia, comorbidities, polypharmacy, and side effects. Current national dementia guidelines lack recommendations for this group. This study assessed guideline awareness, usage, and pharmacological management practices for dementia in the oldest old and frail across Europe.

METHODS

An online anonymous survey was distributed in 2023 to the European Geriatric Medicine Society Dementia Special Interest Group and their contacts to investigate guideline awareness and pharmacological practices for the oldest old and frail. The CHERRIES checklist was followed for reporting. Responses were summarized using descriptive statistics and quotations of free text responses.

RESULTS

Forty-nine responses from fourteen countries were received. A total of 76.6% were aware of a national dementia guideline and 86.9% applied it frequently. Acetylcholinesterase inhibitors (AChEIs) were generally used as a first-line treatment in mild-to-moderate Alzheimer's disease (AD) (91.6% and 93.4%). Memantine was added or replaced AChEIs as dementia severity progresses. Gingko biloba was considered in mild and moderate AD (23.6% and 22.7%, respectively). Off-label drug use was common in other types of dementia. 88.5% of respondents reported no difference in treatment compared with a younger population.

CONCLUSION

There was awareness of various dementia guidelines, but none addressed the management of the oldest old and frail. Most respondents did not adapt their practices for this group, but many reported off-label treatments which resulted in non-evidence-based prescribing, overprescribing, and a lack of deprescribing. European consensus to guide the management of dementia in this complex population is needed.

In vivo-measured Lewy body pathology is associated with neuropsychiatric symptoms across the Alzheimer's disease continuum

Intracellular alpha-synuclein aggregates, known as Lewy bodies (LB), are commonly observed in Alzheimer's disease (AD) dementia. Post-mortem studies have shown a higher frequency of neuropsychiatric symptoms among individuals with AD and LB co-pathology. However, the effects of in vivo-measured LB pathology on neuropsychiatric symptoms in AD remain underexplored. This study aimed to evaluate cross-sectional and longitudinal effects of in vivo-measured LB pathology on neuropsychiatric symptoms across the AD continuum. We analyzed data from 1,169 participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI). Participants had in vivo measures of LB pathology (assessed using an alpha-synuclein seed amplification assay), amyloid-beta (Aβ) and phosphorylated tau (p-tau) levels in cerebrospinal fluid (CSF), and neuropsychiatric symptoms evaluated using the Neuropsychiatric Inventory-Questionnaire (NPI-Q). Logistic and Cox proportional hazards regression models were used to assess cross-sectional and longitudinal effects, respectively, adjusting for age, sex, and cognitive status. Participants had a mean baseline age of 73.05 (SD 7.22) years, 47.13% were women, 426 (36.44%) cognitively unimpaired, and 743 (63.56%) cognitively impaired. In cross-sectional analyses, LB pathology was associated with higher rates of anxiety, apathy, motor disturbances, and appetite disturbances. In longitudinal analyses, LB pathology increased the risk of developing psychosis and anxiety. These effects were independent of Aβ and p-tau. Our results suggest that in vivo-measured LB pathology is closely associated with neuropsychiatric symptoms across the AD continuum. These findings underscore the potential of in vivo LB detection as a marker for identifying individuals at increased risk of neuropsychiatric symptoms, both in clinical trials and in clinical practice.

Application of mini-mental state examination and Montreal Cognitive Assessment in the diagnosis of dementia with Lewy bodies and Alzheimer's disease

BACKGROUND

Dementia with Lewy Bodies (DLB) and Alzheimer's disease (AD) are two types of dementia with a relatively high incidence, and their clinical manifestations are easily confused. However, the cognitive impairment characteristics of the two diseases are different, and the results of cognitive assessment can help the diagnosis of the disease.

OBJECTIVE

To explore the different characteristics of Mini-mental State Examination (MMSE) and Montreal Cognitive Assessment Scale (MoCA) in DLB and AD patients, and to explore potential markers to distinguish AD and DLB.

METHODS

This study included 66 patients with DLB, 81 with AD, and 58 cognitively normal subjects. All of them completed MMSE, MoCA, and Clinical Dementia Rating (CDR).

RESULTS

Compared with NC, both DLB and AD participants demonstrated statistically lower scores in the total and subitem domains of MMSE and MoCA (p < 0.05). When CDR was less than 2, DLB patients had better performance than AD in two subtests including memory and orientation (p < 0.05), demonstrated worse performance in most subtest including executive function, writing, visuospatial abilities, and attention (p < 0.05). Nonetheless, no notable distinction in scores existed for the DLB and AD groups with a CDR score of 2 (p > 0.05).

CONCLUSION

We observed distinct cognitive performances in subjects from both the DLB and AD groups across different stages of dementia. Our study confirms the high value of MMSE and MoCA in distinguishing patients with DLB and AD in the early stages of the disease, and they can improve the differential diagnosis of DLB and AD.

Salivary biomarkers for the molecular diagnosis of dementia with Lewy bodies

BackgroundDespite dementia with Lewy bodies (DLB) being the second most common form of neurodegenerative dementia, more than 80% of DLB cases are initially misdiagnosed. Alpha-synuclein (a-syn) and tau species have been detected in peripheral tissues and biological fluids of DLB patients and among different biological fluids, saliva represent an easely accessible and non-invasive source for biomarker detection.ObjectiveThis study aimed to investigate salivary a-syn and tau species as molecular disease biomarkers, assessing their potential in the diagnosis of DLB and in the differential diagnosis on respect to Alzheimer's disease (AD) and Parkinson's disease (PD).MethodsWe measured total and oligomeric a-syn, total-tau, and S199-phosphorylated-tau (pS199-tau) in the saliva of 21 DLB, 20 AD, 20 PD patients, and 20 healthy subjects (HS) using quantitative enzyme-linked immunosorbent assay (ELISA) analyses.ResultsSalivary total a-syn was not significantly changed between the different groups, whereas all pathological groups had a higher oligomeric a-syn concentration than HS. Salivary total-tau concentration was higher in all the pathological groups than HS, whereas the concentrations did not differ among patients' groups. Conversely, salivary levels of pS199-tau was higher in DLB and AD patients than in HS and PD patients. Both correlation matrix and principal component analysis showed that core clinical DLB features were related to a-syn pathology, while cognitive decline was associated with salivary levels of pS199-tau in both DLB and AD patients. Receiver operating characteristic analysis reported high diagnostic accuracy for both a-syn oligomers and pS199-tau, between DLB and HS, and an adequate accuracy between DLB and PD. Conversely, the diagnostic accuracy was not optimal between DLB patients and AD patients.ConclusionsThese findings provide preliminary evidence that salivary a-syn and tau species might be promising in identifying DLB patients on respect to PD patients and HS, while the diagnostic potential is limited on respect to AD.

Engrams across diseases: Different pathologies - unifying mechanisms?

Memories are our reservoir of knowledge and thus, are crucial for guiding decisions and defining our self. The physical correlate of a memory in the brain is termed an engram and since decades helps researchers to elucidate the intricate nature of our imprinted experiences and knowledge. Given the importance that memories have for our lives, their impairment can present a tremendous burden. In this review we aim to discuss engram malfunctioning across diseases, covering dementia-associated pathologies, epilepsy, chronic pain and psychiatric disorders. Current neuroscientific tools allow to witness the emergence and fate of engram cells and enable their manipulation. We further suggest that specific mechanisms of mnemonic malfunction can be derived from engram cell readouts. While depicting the way diseases act on the mnemonic component - specifically, on the cellular engram - we emphasize a differentiation between forms of amnesia and hypermnesia. Finally, we highlight commonalities and distinctions of engram impairments on the cellular level across diseases independent of their pathogenic origins and discuss prospective therapeutic measures.

Visual hallucinations in Parkinson's disease: spotlight on central cholinergic dysfunction

Visual hallucinations are a common non-motor feature of Parkinson's disease and have been associated with accelerated cognitive decline, increased mortality and early institutionalization. Despite their prevalence and negative impact on patient outcomes, the repertoire of treatments aimed at addressing this troubling symptom is limited. Over the past two decades, significant contributions have been made in uncovering the pathological and functional mechanisms of visual hallucinations, bringing us closer to the development of a comprehensive neurobiological framework. Convergent evidence now suggests that degeneration within the central cholinergic system may play a significant role in the genesis and progression of visual hallucinations. Here, we outline how cholinergic dysfunction may serve as a potential unifying neurobiological substrate underlying the multifactorial and dynamic nature of visual hallucinations. Drawing upon previous theoretical models, we explore the impact that alterations in cholinergic neurotransmission has on the core cognitive processes pertinent to abnormal perceptual experiences. We conclude by highlighting that a deeper understanding of cholinergic neurobiology and individual pathophysiology may help to improve established and emerging treatment strategies for the management of visual hallucinations and psychotic symptoms in Parkinson's disease.

Tracer kinetic model detecting heterogeneous blood-brain barrier permeability to water and contrast agent in Alzheimer's disease and dementia with Lewy bodies

INTRODUCTION

Blood-brain barrier (BBB) breakdown is essential in Alzheimer's disease (AD) and dementia with Lewy bodies (DLB), whereas the variability in BBB permeability to water and contrast agent is less clear.

METHODS

We investigated BBB permeability to water and contrast agent simultaneously using a novel tracer kinetic model for dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in 42 AD patients, 22 DLB patients, and 22 healthy controls. All participants underwent clinical, cognitive, and MRI assessments.

RESULTS

AD patients exhibited a significant reduction in the water exchange rates across the BBB, whereas DLB patients showed a significant increase in BBB permeability to contrast agent. Moreover, BBB permeability to both water and contrast agent in multiple brain regions demonstrated correlations with clinical severity.

DISCUSSION

The simultaneous evaluation of BBB permeability to water and contrast agent based on the proposed model highlights the heterogeneous patterns of BBB breakdown in AD and DLB.

HIGHLIGHTS

We measured blood-brain barrier (BBB) permeability to water and contrast agent based on dynamic contrast-enhanced magnetic resonance imaging. Alzheimer's disease (AD) is characterized by lower water exchange rates across the BBB. Dementia with Lewy bodies exhibits higher BBB permeability to contrast agent. BBB permeability is related to cognitive impairment and disease burden. BBB permeability to water was negatively associated with that to contrast agent.

Fast-spiking parvalbumin-positive interneurons: new perspectives of treatment and future challenges in dementia

Central nervous system parvalbumin-positive interneurons (PV-INs) are crucial and highly vulnerable to various stressors. They also play a significant role in the pathological processes of many neuropsychiatric diseases, especially those associated with cognitive impairment, such as Alzheimer's disease (AD), vascular dementia (VD), Lewy body dementia, and schizophrenia. Although accumulating evidence suggests that the loss of PV-INs is associated with memory impairment in dementia, the precise molecular mechanisms remain elusive. In this review, we delve into the current evidence regarding the physiological properties of PV-INs and summarize the latest insights into how their loss contributes to cognitive decline in dementia, particularly focusing on AD and VD. Additionally, we discuss the influence of PV-INs on brain development, the variations in their characteristics across different types of dementia, and how their loss affects the etiology and progression of cognitive impairments. Ultimately, our goal is to provide a comprehensive overview of PV-INs and to consider their potential as novel therapeutic targets in dementia treatment.

Enhancing sleep quality in synucleinopathies through physical exercise

During sleep, several crucial processes for brain homeostasis occur, including the rearrangement of synaptic connections, which is essential for memory formation and updating. Sleep also facilitates the removal of neurotoxic waste products, the accumulation of which plays a key role in neurodegeneration. Various neural components and environmental factors regulate and influence the physiological transition between wakefulness and sleep. Disruptions in this complex system form the basis of sleep disorders, as commonly observed in synucleinopathies. Synucleinopathies are neurodegenerative disorders characterized by abnormal build-up of α-synuclein protein aggregates in the brain. This accumulation in different brain regions leads to a spectrum of clinical manifestations, including hypokinesia, cognitive impairment, psychiatric symptoms, and neurovegetative disturbances. Sleep disorders are highly prevalent in individuals with synucleinopathies, and they not only affect the overall well-being of patients but also directly contribute to disease severity and progression. Therefore, it is crucial to develop effective therapeutic strategies to improve sleep quality in these patients. Adequate sleep is vital for brain health, and the role of synucleinopathies in disrupting sleep patterns must be taken into account. In this context, it is essential to explore the role of physical exercise as a potential non-pharmacological intervention to manage sleep disorders in individuals with synucleinopathies. The current evidence on the efficacy of exercise programs to enhance sleep quality in this patient population is discussed.

Refractory Psychosis as a Red Flag for End of Life in Individuals With Dementia With Lewy Bodies: A Case Series and Re-analysis of Prior Qualitative Data

OBJECTIVES

Many individuals with dementia with Lewy bodies (DLB) die of disease-related complications, but predicting the end of life can be challenging. We identified a phenotype associated with approaching end of life.

METHODS

We present 4 exemplar cases where individuals with DLB experienced refractory psychosis before death. We reviewed codebooks and quotes from 3 studies regarding end-of-life experiences in DLB to identify experiences that aligned with this phenotype.

RESULTS

In addition to the 4 cases, family caregivers in prior studies described prominent worsening of psychosis before death in some individuals with DLB. The worsening often occurred several months before death and was sometimes associated with rapid deterioration. Worsening psychosis was the prominent symptom and was not initially accompanied by cognitive or physical decline. In many cases, the refractory psychosis resulted in inpatient psychiatric hospitalization or residential care, but these scenarios were challenging because of the individual's behavior.

CONCLUSION

Refractory psychosis in DLB, particularly out of proportion to other symptoms, may be a signal of approaching the end of life. More research is needed to understand this phenomenon and to develop effective and safe treatments for psychosis in DLB.

Association of Alzheimer's and Lewy body disease pathology with basal forebrain volume and cognitive impairment

BACKGROUND

Degeneration of the basal forebrain cholinergic system is a hallmark feature shared by Alzheimer's disease (AD) and Lewy body disease (LBD) whereas hippocampus atrophy is more specifically related to AD. We aimed to investigate the relationship between basal forebrain and hippocampus atrophy, cognitive decline, and neuropathology in a large autopsy sample.

METHODS

Data were obtained from the National Alzheimer's Coordinating Center (NACC). Basal forebrain and hippocampus volumes were extracted using an established automated MRI volumetry approach. Associations of regional volumes with pathological markers (Braak stage, CERAD score, and McKeith criteria for LB pathology) and cognitive performance were assessed using Bayesian statistical methods.

RESULTS

We included people with autopsy-confirmed pure AD (N = 248), pure LBD (N = 22), and mixed AD/LBD (N = 185). Posterior basal forebrain atrophy was most severe in mixed AD/LB pathology compared to pure AD (Bayes factor against the null hypothesis BF10 = 16.2) or pure LBD (BF10 = 4.5). In contrast, hippocampal atrophy was primarily associated with AD pathology, independent of LB pathology (pure AD vs. pure LBD: BF10 = 166, pure AD vs. mixed AD/LBD: BF10 = 0.11, pure LBD vs. mixed AD/LBD: BF10 = 350). Cognitive performance was more impaired in AD pathology groups, with Braak stage being the strongest predictor. Hippocampal volume partially mediated this relationship between tau pathology and cognitive impairment, while basal forebrain volume had a limited role in mediating the relationship between pathological burden and cognitive outcomes.

CONCLUSION

In a heterogeneous autopsy sample, AD and LB pathology both contribute to cholinergic basal forebrain degeneration whereas hippocampus atrophy is more specifically related to AD pathology. Cognitive deficits are primarily associated with tau pathology which is partly mediated by hippocampus, but not basal forebrain atrophy.

Challenges in the management of visual and tactile hallucinations in elderly people

This letter provides a concise review of the pertinent literature on visual and tactile hallucinations in elderly patients. The discussion addresses differential diagnoses and potential underlying mechanisms, as well as the psychopathology associated with tactile hallucinations, and emphasizes the necessity for investigation into the possibility of coexisting delusional infestation (parasitosis). These symptoms frequently manifest in patients with primary psychotic disorders, organic mental disorders, and substance use disorders. The proposed pathophysiological mechanisms may involve dopaminergic imbalances and dysfunction of the striatal dopamine transporter.

Antidopaminergic medications in Huntington's disease

Huntington's disease (HD) is a progressive neurodegenerative disorder marked by motor, cognitive, and behavioral impairments. Antidopaminergic medications (ADMs), such as VMAT2 inhibitors and antipsychotics, are commonly used to manage HD motor disturbances and behavioral disorders. For patients and caregivers, ADMs are an important tool for managing symptoms that negatively affect daily life. However, the impact of ADM use in HD is not firmly understood due to a lack of robust, systematic studies that assessed their overall effect on HD disease. A mounting body of evidence suggests these medications may be associated with worse clinical measures of cognitive function and functional impairment. While regulatory guidelines highlight adverse effects like sedation, cognitive dysfunction, and extrapyramidal symptoms, it is unclear whether ADMs directly impact disease progression or if the side effects mimic or exacerbate measures of HD symptoms in clinical trials. Given ADM effects on the central nervous system and biological uncertainty within HD outcomes, clinical trial designs should recognize the impact of ADMs on key outcomes, as measured by acceptable scales including Total Functional Capacity, Stoop Word Reading, Symbol Digit Modality Test, and the composite Unified Huntington's Disease Rating Scale. The development of novel HD interventions requires consideration of concomitant ADM use that may influence measures of disease presentation. In this review, we highlight the role of ADMs in HD management, their symptomatic benefits and potential risks, especially with high dose associated side effects, interactions with CYP2D6 inhibitors, and the individualized need for careful dose monitoring for clinical care and trial design.

Positron emission tomography tracers for synucleinopathies

Synucleinopathies, such as Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy, are characterized by the aggregation of α-synuclein. Variations in brain distribution allow for differentiation among these diseases and facilitate precise clinical diagnosis. However, distinguishing between synucleinopathies and Parkinsonism with tauopathies poses a challenge, significantly impacting clinical drug development. Therefore, molecular imaging is crucial for synucleinopathies, particularly for clinical diagnosis, assessment of drug efficacy, and disease surveillance. In recent years, advances in molecular imaging have led to rapid development of α-synuclein-specific tracers for positron emission tomography (PET), most of which are still in pre-clinical stages. Interestingly, some of these tracers share similar compound skeletal structures and are currently undergoing optimization for clinical application. Despite this progress, there remain challenges in developing α-synuclein tracers. This review summarizes recent findings on promising PET tracers and discusses representative compounds' characteristics while offering suggestions for further research orientation.

[Clinical guidelines «Cognitive disorders in the elderly and senile persons»]

Clinical guidelines «Cognitive disorders in the elderly and senile persons».

Probiotics as Potential Treatments for Neurodegenerative Diseases: a Review of the Evidence from in vivo to Clinical Trial

Neurodegenerative diseases (NDDs), characterized by the progressive deterioration of the structure and function of the nervous system, represent a significant global health challenge. Emerging research suggests that the gut microbiota plays a critical role in regulating neurodegeneration via modulation of the gut-brain axis. Probiotics, defined as live microorganisms that confer health benefits to the host, have garnered significant attention owing to their therapeutic potential in NDDs. This review examines the current research trends related to the microbiome-gut-brain axis across various NDDs, highlighting key findings and their implications. Additionally, the effects of specific probiotic strains, including Lactobacillus plantarum, Bifidobacterium breve, and Lactobacillus rhamnosus, on neurodegenerative processes were assessed, focusing on their potential therapeutic benefits. Overall, this review emphasizes the potential of probiotics as promising therapeutic agents for NDDs, underscoring the importance of further investigation into this emerging field.

The causal role of lipids in dementia: A Mendelian randomization study

Background

Increasing evidence suggests that abnormal lipid metabolism is one of the pathogeneses of dementia. It is necessary to reveal the relationship between lipids and dementia.

Objective

This study used bidirectional two-sample Mendelian randomization to explore the causal relationship between 179 lipid species and the risk of dementia.

Methods

We assessed the causal effects of 179 lipid species and four subtypes of dementia including Alzheimer's disease (AD), vascular dementia (VaD), frontotemporal dementia (FTD), and dementia with Lewy bodies (DLB). Inverse variance weighting, MR-Egger method, weighted median, simple mode, and weighted mode were used to analyze the relationship between lipids and dementia. Cochran's Q, MR-Egger intercept test, and MR-PRESSO test were used to test the heterogeneity and pleiotropy of the results. In addition, we performed an inverse MR analysis testing the causal effects of dementia on lipids.

Results

Our study revealed causal effects of glycerophospholipid, glycerolipid, and sterol on the risk of dementia. Phosphatidylcholine, phosphatidylinositol, and triglycerides play significant roles in AD. Notably, phosphatidylcholine played a protective role in both FTD and DLB. However, this study did not observe a significant effect of phosphatidylinositol on FTD. In the case of VaD, not only glycerophospholipid, but also glycerolipid, exerted an influence, but sterol was also a risk factor.

Conclusions

Our study provided new evidence supporting the causal role of genetically predicted lipid species in dementia. Future clinical trials are necessary to evaluate the potential role of lipid levels in dementia prevention.

Very-Low-Dose Clozapine as Maintenance Treatment for Psychosis in a Patient With Dementia With Lewy Bodies: A Case Report

Dementia with Lewy bodies (DLB) is a neurodegenerative disorder characterized by cognitive decline, motor symptoms, and other neuropsychiatric manifestations, including visual hallucinations, delusions and disorganized thought processes that can configure a psychotic episode. Managing psychosis in DLB is challenging due to hypersensitivity to antipsychotics. This case report describes a 72-year-old female patient with DLB who presented with psychosis and Parkinsonian symptoms. Initial management with olanzapine (10 mg) was effective for psychosis but led to motor worsening. The inclusion of levodopa-carbidopa and reduction of olanzapine were not effective in the resolution of symptoms. Transition to clozapine performed and resulted in stabilization of psychotic symptoms and motor symptoms improvement. Initially, the patient presented with severe symptomatic hypotension, that required the tapering off to a very low dose (6.25mg) without severe adverse effects. This report highlights the utility of very-low dose clozapine in managing psychosis in DLB and discusses therapeutic challenges.

Cognitive decline profiles associated with lewy pathology in the context of Alzheimer's disease neuropathologic change

BACKGROUND

Alzheimer's disease neuropathologic change (ADNC) and Lewy pathology (LP) often coexist in cognitively impaired individuals. These pathologies' relative distribution and severity may modify these individuals' clinical presentation, cognitive profile, and prognosis. Therefore, we examined the contributions of LP and concomitant ADNC to disease survival and profiles of cognitive decline in preclinical and clinical stages in a large neuropathologically diagnosed group.

METHODS

We evaluated 597 participants with LP and 491 participants with intermediate/high ADNC in the absence of LP from the National Alzheimer Coordinating Center (NACC) database. At baseline, 237 participants were cognitively normal (CN), 255 were diagnosed with mild cognitive impairment (MCI), and 596 with dementia. Cognition was assessed using three cognitive domain scores (i.e., Memory, Executive, and Language) from the NACC Uniform Dataset (UDS) neuropsychological test battery, MMSE, and Clinical Dementia Rating (CDR). Multivariate adaptive regression splines were used to evaluate associations between baseline cognitive scores and mean annual rate of change over two years. The likelihood of progression to MCI or dementia was assessed using Cox hazard models.

RESULTS

Neocortical LP, independent of the clinical diagnosis, was associated with lower Executive and higher Language and Memory scores at baseline, whereas Braak V-VI neurofibrillary tangle pathology was associated with lower Memory and Language scores. Similarly, neocortical LP was associated with faster Executive decline, whereas Braak V-VI neurofibrillary tangle pathology was associated with faster Memory and Language decline. A clinical diagnosis of Lewy Body Dementia (i.e., a strong LP phenotype) was associated with the LP cognitive profile and shorter disease duration. Progression to incident MCI or dementia was primarily associated with the degree of tau pathology; neocortical LP or a diagnosis of Lewy Body Dementia only predicted progression when those with intermediate/high ADNC were excluded.

CONCLUSIONS

LP and ADNC differentially affected cross-sectional and longitudinal cognitive profiles in a large autopsy sample. Concomitant Braak V-VI neurofibrillary tangle pathology had a strong impact on clinical progression in those with LP, regardless of the initial stage. Thus, LB and ADNC co-pathology interact to affect cognitive domains that may be used to track Lewy Body disease longitudinally and as outcome measures in therapeutic trials.

Amyloid beta biomarker for dementia detection by hyperspectral ophthalmoscope images

The escalating prevalence and economic burden of dementia underscore the urgency for innovative detection methods. This study investigates the potential of hyperspectral imaging (HSI) to detect dementia by analyzing retinal changes associated with amyloid beta (Aβ) formations. Leveraging a dataset of 3,256 ophthalmoscopic images from 137 participants aged 60 to 85 years, categorized into dementia and non-dementia groups via the Mini-Mental State Examination (MMSE), we extracted features from five key regions of interest (ROIs) identified for their pronounced changes in Aβ biomarkers. The analysis revealed that gender does not significantly influence dementia levels, and no substantial spectral differences were observed within the 380 nm to 600 nm wavelength range. However, significant variations in spectral reflection intensity were noted between 600 nm and 780 nm across both genders, suggesting a potential avenue for distinguishing stages of dementia. Despite the impact of diabetes on the vascular system, its stages did not significantly influence dementia development. This research highlights the utility of HSI in identifying dementia-related retinal changes and calls for further exploration into its effectiveness as a diagnostic tool, potentially offering a non-invasive method for early detection of dementia.

Spatial-temporal dynamic evolution of lewy body dementia by metabolic PET imaging

PURPOSE

Lewy body dementia (LBD) is a neurodegenerative disease with high heterogeneity and complex pathogenesis. Our study aimed to use disease progression modeling to uncover spatial-temporal dynamic evolution of LBD in vivo, and to explore differential profiles of clinical features, glucose metabolism, and dopaminergic function among different evolution-related subtypes.

METHODS

A total of 123 participants (31 healthy controls and 92 LBD patients) who underwent 18F-FDG PET scans were retrospectively enrolled. 18F-FDG PET-based Subtype and Stage Inference (SuStaIn) model was established to illustrate spatial-temporal evolutionary patterns and categorize relevant subtypes. Then subtypes and stages were further related to clinical features, glucose metabolism, and dopaminergic function of LBD patients.

RESULTS

This 18F-FDG PET imaging-based approach illustrated two distinct patterns of neurodegenerative evolution originating from the neocortex and basal ganglia in LBD and defined them as subtype 1 and subtype 2, respectively. There were obvious differences between subtypes. Compared with subtype 1, subtype 2 exhibited a greater proportion of male patients (P = 0.045) and positive symptoms such as visual hallucinations (P = 0.033) and fluctuating cognitions (P = 0.033). Cognitive impairment, metabolic abnormalities, dopaminergic dysfunction and progression were all more severe in subtype 2 (all P < 0.05). In addition, a strong association was observed between SuStaIn subtypes and two clinical phenotypes (Parkinson's disease dementia and dementia with Lewy bodies) (P = 0.005).

CONCLUSIONS

Our findings based on 18F-FDG PET and data-driven model illustrated spatial-temporal dynamic evolution of LBD and categorized novel subtypes with different evolutionary patterns, clinical and imaging features in vivo. The evolution-related subtypes are associated with LBD clinical phenotypes, which supports the perspective of existence of distinct entities in LBD spectrum.

Whole-genome sequencing to identify rare variants in East Asian patients with dementia with Lewy bodies

Dementia with Lewy bodies (DLB) is the second most common form of age-related dementia, following Alzheimer's disease (AD). DLB is associated with a worse prognosis than AD and is characterized by a more rapid progression of cognitive impairment and a poorer quality of life. In addition, the pathogenesis of DLB is less understood than that of AD, and only three genes-SNCA (α-synuclein), APOE (apolipoprotein E), and GBA1 (glucosylceramidase beta 1)-have been convincingly demonstrated to be associated with DLB. In this study, we utilized whole-genome sequencing data from 1744 Japanese individuals, comprising 45 DLB patients and 1699 cognitively normal older adults, aiming to identify new genes associated with DLB. Our genome-wide association studies of genes with potentially deleterious mutations identified the CDH23 gene as being associated with DLB, reaching a Bonferroni-corrected significance (P = 7.43 × 10-4). The gene contained three ethnicity-specific heterozygous missense variants (rs181275139, rs563688802, and rs137937502). CDH23 has been linked to deafness syndromes, and DLB patients carrying these mutations displayed symptoms of subjective hearing loss, suggesting a potential association between DLB onset and auditory impairment. Additionally, we explored human leukocyte antigen (HLA) genotypes associated with DLB but found no significant associations. This result suggests that the pathology of DLB differs from that of Parkinson's disease, which has been reported to have an association with HLA. Although a limitation of this study is the lack of replication of our findings, which require further validation in independent cohorts, our study enhances the understanding of the etiology of DLB in the Japanese population and provides new insights into the underlying mechanisms of its pathogenesis.

[Diagnosis and management of delirium in older adults]

Delirium, also known as acute confusional state, is an acute brain disorder characterized by cognitive disturbances, particularly attentional deficits, potential behavioral changes, and altered vigilance, with a sudden onset and fluctuating course. It is a common condition among hospitalized older patients and has serious consequences for the patient, their family, and the healthcare system. It is considered an "acute brain failure" that often occurs in the context of underlying cognitive and cerebral vulnerability, similar to how acute kidney injury complicates chronic kidney disease or how acute heart failure exacerbates chronic heart failure - usually in the presence of a precipitating medical factor, often infectious, metabolic, perioperative, or neurological. This narrative review aims to describe the symptoms that allow the diagnosis of delirium in older adults, the available diagnostic or screening tools, as well as the complex and bidirectional relationships between delirium and dementia. The management of delirium, including non-pharmacological measures, will be discussed, along with symptomatic pharmacological treatments, which should be reserved for severe cases despite their low level of evidence.

PM2.5 induces developmental neurotoxicity in cortical organoids

There is mounting evidence implicating the potential neurotoxic effects of PM2.5 during brain development, as it has been observed to traverse both the placental barrier and the fetal blood-brain barrier. However, the current utilization of 2D cell culture and animal models falls short in providing an accurate representation of human brain development. Consequently, the precise mechanisms underlying PM2.5-induced developmental neurotoxicity in humans remain obscure. To address this research gap, we constructed three-dimensional (3D) cortical organoids that faithfully recapitulate the initial stages of human cerebral cortex development. Our goal is to investigate the mechanisms of PM2.5-induced neurotoxicity using 3D brain organoids that express cortical layer proteins. Our findings demonstrate that exposure to PM2.5 concentrations of 5 μg/mL and 50 μg/mL induces neuronal apoptosis and disrupts normal neural differentiation, thereby suggesting a detrimental impact on neurodevelopment. Furthermore, transcriptomic analysis revealed PM2.5 exposure induced aberrations in mitochondrial complex I functionality, which is reminiscent of Parkinson's syndrome, potentially mediated by misguided axon guidance and compromised synaptic maintenance. This study is a pioneering assessment of the neurotoxicity of PM2.5 pollution on human brain tissues based on 3D cortical organoids, and the results are of great significance in guiding the formulation of the next air pollution prevention and control policies in China to achieve the sustainable improvement of air quality and to formulate pollution abatement strategies that can maximize the benefits to public health.

Association of dementia with the 28-day mortality of sepsis: an observational and Mendelian randomization study

Background

Observational research suggests that individuals with dementia who have sepsis face a higher likelihood of death. However, whether there is a causal relationship between the two remains unknown.

Methods

We analyzed data from patients diagnosed with sepsis and dementia, extracted from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. To examine the correlation between dementia and 28-day mortality in sepsis, we utilized Cox proportional hazards models. Following this, we performed a Mendelian randomization (MR) study with two samples to investigate the potential link between dementia and mortality within 28 days in sepsis.

Results

This study included a total of 22,189 patients diagnosed with sepsis, among whom 1,346 cases (6.1%) had dementia. After adjusting for multiple confounding factors, dementia was associated with an increased risk of 28-day mortality in sepsis (HR = 1.25, 95% CI = 1.12-1.39, p < 0.001). In the MR analysis, there appeared to be a causal relationship between genetically predicted dementia with Lewy bodies (DLB) (OR = 1.093, 95% CI = 1.016-1.177, p = 0.017) and 28-day mortality in sepsis. However, there was no evidence of causality between any dementia (OR = 1.063, 95% CI = 0.91-1.243, p = 0.437), Alzheimer's disease (AD) (OR = 1.126, 95% CI = 0.976-1.299, p = 0.103), vascular dementia (VD) (OR = 1.008, 95% CI = 0.93-1.091, p = 0.844), and the risk of 28-day mortality in sepsis.

Conclusion

In the observational analysis, dementia was associated with an increased risk of 28-day mortality in septic patients. However, in the MR analysis, only DLB was associated with increased 28-day mortality in septic patients, with no observed correlation for other dementia subtypes.

Do Statins Affect Cognitive Health? A Narrative Review and Critical Analysis of the Evidence

PURPOSE OF REVIEW

Statins are the first-line treatment for hypercholesterolemia and play a key role in the prevention of cardiovascular disease (CVD). Current studies report mixed effects of statins on cognitive health, including harmful, neutral, and protective outcomes. However, these ongoing controversies about the potential cognitive adverse effects of statins may compromise their use in CVD prevention. Several factors may influence how statins affect cognition, including the unique cholesterol homeostasis in the brain, the limited permeability of the blood-brain barrier to lipoproteins, and the varying lipophilicity of different statins. This review examines the evidence linking statins to cognitive function and considers the effect of different dosages and treatment durations.

RECENT FINDINGS

Earlier studies suggested cognitive disturbances with statins, but recent evidence does not strongly support a link between statins and cognitive impairment. In fact, observational studies suggest potential neuroprotective benefits, though biases like selection bias, confounding and reverse causation limit definitive conclusions. Two large randomized controlled trials, STAREE and PREVENTABLE, are underway, and their results are expected to address some of these gaps in the literature. Due to insufficient evidence in the current literature, well-designed randomized controlled trials are needed for a better understanding of statins' effects on cognition. More data is needed regarding statin type, dose intensity, and treatment duration, which may affect cognitive outcomes. Future studies are also needed to examine how statins may affect cognition in specific high-risk groups, such as individuals with mild cognitive impairment, diabetes, cardiovascular disease, or chronic kidney disease.

Validity and reliability of the Turkish version of the ALBA screening instrument for Lewy body dementia in older adults

ALBA screening instrument (ASI) has been demonstrated to be an effective, cheap, and noninvasive clinical instrument to screen for Lewy body dementia (LBD). We aimed to determine the validity and reliability of the Turkish version of ASI (ASI-T) in patients with LBD and to investigate the discriminative power of the test in patients with Alzheimer's Disease (AD), LBD, and cognitively healthy older adults (controls). 172 older adults over 60 years of age (43 with LBD, 41 AD, and 88 controls) were included. The sensitivity and specificity of the instrument were determined. A significant difference was found in ASI-T total score between people with LBD versus the controls (t=-9.259; p < 0.001), and versus patients with AD (t = 3.490; p = 0.001). Internal consistency of the ASI-T was good(Cronbach's alpha = 0.81). The cutoff score of 7 showed sensitivity (86%) and specificity (81%) (AUC= 0.888,CI0.95, p < 0.001) compared to controls. Also, compared to AD, it showed sensitivity (86%) and specificity(70%) (AUC = 0.590,CI .95, p < 0.001). Moreover, ASI-T demonstrated a significant concurrent validity with MMSE (r = -0.62; p < 0.001) and MoCA (r = -0.54; p = 0.003). In factor analysis, the five subscales accounted for 60% of the total variance. Our findings suggested that the ASI-T is a reliable, valid, and effective instrument for screening LBD. With acceptable psychometric properties, it has the power to distinguish patients with LBD from controls or those with AD.

Parkinsonian Syndrome Diagnosed via Novel Alpha-Synuclein Skin Biopsy in a Patient Presenting With Catatonic Symptoms

The differential diagnosis of neurocognitive and psychiatric disorders, particularly when symptoms overlap significantly, poses a substantial challenge in clinical practice. Parkinson's disease (PD), Lewy body dementia, and catatonia are distinct conditions that can present with similar motor and cognitive symptoms, complicating accurate diagnosis and effective treatment. We report the case of a 45-year-old male patient who presented for electroconvulsive therapy (ECT) evaluation. He was initially diagnosed with major depressive disorder with catatonic features. The clinical overlap between psychomotor retardation due to severe depression and bradykinesia, characteristic of PD, led to a reevaluation of the initial diagnosis. A novel diagnostic tool, the alpha-synuclein skin biopsy, was utilized and it revealed the presence of alpha-synuclein pathology. This ultimately led to the diagnosis of parkinsonian syndrome. The positive alpha-synuclein biopsy result was pivotal in distinguishing between catatonia and parkinsonian syndrome, facilitating the initiation of appropriate treatment. The patient's subsequent improvement underscores the importance of considering neurodegenerative etiologies in patients with atypical or treatment-resistant psychiatric symptoms. This case underscores the need for a comprehensive, multidisciplinary approach to evaluating patients with overlapping psychiatric and neurological symptoms. Integrating novel diagnostic tools, such as the alpha-synuclein biopsy, into clinical practice may enhance diagnostic accuracy and improve patient outcomes.

Mitochondrial Dysfunction in Parkinson's Disease: A Contribution to Cognitive Impairment?

Among the non-motor symptoms associated with Parkinson's disease (PD), cognitive impairment is one of the most common and disabling. It can occur either early or late during the disease, and it is heterogeneous in terms of its clinical manifestations, such as Subjective Cognitive Dysfunction (SCD), Mild Cognitive Impairment (MCI), and Parkinson's Disease Dementia (PDD). The aim of the present review is to delve deeper into the molecular mechanisms underlying cognitive decline in PD. This is extremely important to delineate the guidelines for the differential diagnosis and prognosis of the dysfunction, to identify the molecular and neuronal mechanisms involved, and to plan therapeutic strategies that can halt cognitive impairment progression. Specifically, the present review will discuss the pathogenetic mechanisms involved in the progression of cognitive impairment in PD, with attention to mitochondria and their contribution to synaptic dysfunction and neuronal deterioration in the brain regions responsible for non-motor manifestations of the disease.

Understanding the nature and impact of cognitive fluctuations and sleep disturbances in dementia with Lewy bodies: A qualitative caregiver study

Objectives

Dementia with Lewy bodies is characterised by rapid fluctuations in attention, which are known as "cognitive fluctuations." Despite the fact that cognitive fluctuations are considered to be a core dementia with Lewy bodies symptom, they are very difficult to define and measure using existing quantitative subjective measurement tools, which are typically completed by caregivers. Cognitive fluctuations are also likely to be influenced by various aspects of sleep, but this is as yet unexplored. The primary aim of this qualitative study was to investigate the phenomenology of cognitive fluctuations in dementia with Lewy bodies by understanding caregiver experiences.

Methods

Seven caregivers of people with dementia with Lewy bodies completed one-to-one semistructured interviews, which were conducted by telephone. Caregivers were asked to describe the nature, frequency, duration and potential triggers of cognitive fluctuations that were experienced by the individual with dementia with Lewy bodies. Caregivers were also asked about the subjective sleep experience of the individual with dementia with Lewy bodies, and about their own sleep experiences. Interviews were audio recorded, transcribed verbatim and analysed using Thematic Analysis.

Results

Caregivers reported that there was a great deal of individual variation in the frequency, duration and severity of cognitive fluctuations. Patient sleep disturbances, including excessive daytime sleepiness, nocturnal awakenings, restless legs and sleep apnoea, were common. However, the impact of sleep alterations or experiences upon the fluctuations was reported to be less clear. Caregivers also reported that their own sleep was negatively affected, potentially due to actively listening for overnight events and behaviours.

Conclusions

Qualitatively, caregivers report that dementia with Lewy bodies cognitive fluctuations show large individual variations in terms of their frequency, duration and severity, but that subjectively, sleep may not consistently influence this symptom. Specific, caregiver-focussed interventions are likely to be necessary to maintain good sleep health in dementia with Lewy bodies caregivers.

The relationship between anticholinergic burden and frailty in the year preceding a diagnosis of dementia with Lewy bodies

INTRODUCTION

Little is known regarding the relationship between anticholinergic medications and frailty in dementia with Lewy bodies (DLB).

METHODS

Anticholinergic Cognitive Burden Scale (ACB) and Claims-based Frailty Index scores were calculated for 12 months prior to the dementia diagnosis using electronic medical record and claims data. Logistic regression was used to estimate the association between ACB and odds of frailty.

RESULTS

Compared to controls (n = 525), a diagnosis of DLB (n = 175; adjusted odds ratio [aOR]: 15.1, 95% confidence interval [CI]: 7.0-33.9) or Alzheimer's disease (AD: n = 525; aOR = 7.7, 95% CI: 4.4-13.7) was associated with an increased odds of frailty. Patients with DLB had greater prescriptions for anticholinergic medications than patients with AD (p B < 0.001; 23%  vs 9.7%). ACB was positively correlated with frailty for all groups (r = 0.30 to 0.47, p < 0.001).

DISCUSSION

Cumulative anticholinergic burden may be a modifiable predictor of frailty among older adults, including those newly diagnosed with dementia.

Highlights

Patients with newly diagnosed dementia with Lewy bodies (DLB) are more likely to have prescriptions for anticholinergic medications relative to patients newly diagnosed with Alzheimer's disease (AD) and older adults without documented cognitive impairment.In the year prior to a documented dementia diagnosis, 74% of patients with DLB and 66% of patients with AD had evidence of frailty.Anticholinergic medication burden was associated with frailty among all older adults in the study, including those without a dementia diagnosis.

MRI Signature of α-Synuclein Pathology in Asymptomatic Stages and a Memory Clinic Population

Importance

The lack of an in vivo measure for α-synuclein (α-syn) pathology until recently has limited thorough characterization of its brain atrophy pattern, especially during early disease stages.

Objective

To assess the association of state-of-the-art cerebrospinal fluid (CSF) seed amplification assays (SAA) α-syn positivity (SAA α-syn+) with magnetic resonance imaging (MRI) structural measures, across the continuum from clinically unimpaired (CU) to cognitively impaired (CI) individuals, in 3 independent cohorts, and separately in CU and CI individuals, the latter reflecting a memory clinic population.

Design, Setting, and Participants

Cross-sectional data were used from the Swedish BioFINDER-2 study (inclusion, 2017-2023) as the discovery cohort and the Swedish BioFINDER-1 study (inclusion, 2007-2015) and Alzheimer's Disease Neuroimaging Initiative (ADNI; inclusion 2005-2022) as replication cohorts. All cohorts are from multicenter studies, but the BioFINDER cohorts used 1 MRI scanner. CU and CI individuals fulfilling inclusion criteria and without missing data points in relevant metrics were included in the study. All analyses were performed from 2023 to 2024.

Exposures

Presence of α-syn pathology, estimated by baseline CSF SAA α-syn.

Main Outcomes and Measures

The primary outcomes were cross-sectional structural MRI measures either through voxel-based morphometry (VBM) or regions of interest (ROI) including an automated pipeline for cholinergic basal forebrain nuclei CH4/4p (nucleus basalis of Meynert [NBM]) and CH1/2/3. Secondary outcomes were domain-specific cross-sectional cognitive measures. Analyses were adjusted for CSF biomarkers of Alzheimer pathology.

Results

A total of 2961 participants were included in this study: 1388 (mean [SD] age, 71 [10] years; 702 female [51%]) from the BioFINDER-2 study, 752 (mean [SD] age, 72 [6] years; 406 female [54%]) from the BioFINDER-1 study, and 821 (mean [SD] age, 75 [8] years; 449 male [55%]) from ADNI. In the BioFINDER-2 study, VBM analyses in the whole cohort revealed a specific association between SAA α-syn+ and the cholinergic NBM, even when adjusting for Alzheimer copathology. ROI-based analyses in the BioFINDER-2 study focused on regions involved in the cholinergic system and confirmed that SAA α-syn+ was indeed independently associated with smaller NBM (β = -0.271; 95% CI, -0.399 to -0.142; P <.001) and CH1/2/3 volumes (β = -0.227; 95% CI, -0.377 to -0.076; P =.02). SAA α-syn+ was also independently associated with smaller NBM volumes in the separate CU (β = -0.360; 95% CI, -0.603 to -0.117; P =.03) and CI (β = -0.251; 95% CI, -0.408 to -0.095; P =.02) groups. Overall, the association between SAA α-syn+ and NBM volume was replicated in the BioFINDER-1 study and ADNI cohort. In CI individuals, NBM volumes partially mediated the association of SAA α-syn+ with attention/executive impairments in all cohorts (BioFINDER-2, β = -0.017; proportion-mediated effect, 7%; P =.04; BioFINDER-1, β = -0.096; proportion-mediated effect, 19%; P =.04; ADNI, β = -0.061; proportion-mediated effect, 20%; P =.007).

Conclusions and Relevance

In this cohort study, SAA α-syn+ was consistently associated with NBM atrophy already during asymptomatic stages. Further, in memory clinic CI populations, SAA α-syn+ was associated with NBM atrophy, which partially mediated α-syn-induced attention/executive impairment.

The epigenetic modification of DNA methylation in neurological diseases

Methylation, a key epigenetic modification, is essential for regulating gene expression and protein function without altering the DNA sequence, contributing to various biological processes, including gene transcription, embryonic development, and cellular functions. Methylation encompasses DNA methylation, RNA methylation and histone modification. Recent research indicates that DNA methylation is vital for establishing and maintaining normal brain functions by modulating the high-order structure of DNA. Alterations in the patterns of DNA methylation can exert significant impacts on both gene expression and cellular function, playing a role in the development of numerous diseases, such as neurological disorders, cardiovascular diseases as well as cancer. Our current understanding of the etiology of neurological diseases emphasizes a multifaceted process that includes neurodegenerative, neuroinflammatory, and neurovascular events. Epigenetic modifications, especially DNA methylation, are fundamental in the control of gene expression and are critical in the onset and progression of neurological disorders. Furthermore, we comprehensively overview the role and mechanism of DNA methylation in in various biological processes and gene regulation in neurological diseases. Understanding the mechanisms and dynamics of DNA methylation in neural development can provide valuable insights into human biology and potentially lead to novel therapies for various neurological diseases.

Exploring the causal effects of serum lipids and lipidomes on lewy body dementia: a Mendelian randomization study

Background

Lewy body dementia (LBD) is a neurodegenerative disorder characterized by the accumulation of Lewy bodies, which primarily composed of misfolded alpha-synuclein (αS). The development of LBD and APOE4 subtypes is thought to be associated with disorders of lipid metabolism. In this study, we investigated the causal relationship between serum lipids, liposomes and LBD using a two-sample Mendelian randomization (TSMR) method.

Methods

A TSMR analysis of genome-wide association study (GWAS) data for 8 serum lipids, 179 lipidomes components, LBD and its subtypes was performed, using inverse variance weighted as the primary outcome. To ensure robustness, the sensitivity analyses including MR Pleiotropy RESidual Sum and Outlier, Cochran's test, leave-one-out method and funnel plots were performed.

Results

In this study, we found that low-density lipoprotein cholesterol (LDL-C) (OR=1.45, 95% CI=1.19-1.77, P<0.001) and remnant cholesterol (RC) (OR=2.64, 95% CI=1.64-4.28, P<0.001) had significant positive causal effects on LBD, and RC also had a positive effect on LBD in carriers of the APOE4 gene. The results of lipidome analysis showed that phosphatidylcholine (PC) (O-16:0_20:4) levels (OR=0.86, 95% CI=0.75-0.98, P=0.02) and PC (O-18:1_20:4) levels (OR=0.76, 95% CI=0.65-0.89, P <0.001) had negative causal effects on LBD, whereas phosphatidylinositol (PI) (18:1_20:4) levels had a positive causal effect on LBD (OR=1.19, 95% CI=1.02-1.39, P=0.03). For LBD with APOE4 carriers, high levels of PC (16:1_18:0) and PC (O-18:2_18:1) had a significant positive effect, while high levels of PC (O-16:1_18:0), phosphatidylethanolamine (PE) (O-18:2_18:1), sphingomyelin (SM) (d38:2), and triacylglycerol (TAG) (56:5) significantly reduced the risk. No heterogeneity and horizontal pleiotropy were observed in sensitivity analysis.

Conclusion

Elevated LDL-C and RC levels are significant risk factors for LBD, with RC also impacting APOE4-carrying LBD. Glycerophospholipids play a crucial role in the pathogenesis of LBD, but the specific components that play a role differ from those with the APOE4 carries. These findings highlight the importance of lipid metabolism in LBD and APOE4 subtypes.

Blood-brain barrier breakdown in dementia with Lewy bodies

BACKGROUND

Blood-brain barrier (BBB) dysfunction has been viewed as a potential underlying mechanism of neurodegenerative disorders, possibly involved in the pathogenesis and progression of Alzheimer's disease (AD). However, a relation between BBB dysfunction and dementia with Lewy bodies (DLB) has yet to be systematically investigated. Given the overlapping clinical features and neuropathology of AD and DLB, we sought to evaluate BBB permeability in the context of DLB and determine its association with plasma amyloid-β (Aβ) using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).

METHODS

For this prospective study, we examined healthy controls (n = 24, HC group) and patients diagnosed with AD (n = 29) or DLB (n = 20) between December 2020 and April 2022. Based on DCE-MRI studies, mean rates of contrast agent transfer from intra- to extravascular spaces (Ktrans) were calculated within regions of interest. Spearman's correlation and multivariate linear regression were applied to analyze associations between Ktrans and specific clinical characteristics.

RESULTS

In members of the DLB (vs HC) group, Ktrans values of cerebral cortex (p = 0.024), parietal lobe (p = 0.007), and occipital lobe (p = 0.014) were significantly higher; and Ktrans values of cerebral cortex (p = 0.041) and occipital lobe (p = 0.018) in the DLB group were significantly increased, relative to those of the AD group. All participants also showed increased Ktrans values of parietal ( β  = 0.391; p = 0.001) and occipital ( β  = 0.357; p = 0.002) lobes that were significantly associated with higher scores of the Clinical Dementia Rating, once adjusted for age and sex. Similarly, increased Ktrans values of cerebral cortex ( β  = 0.285; p = 0.015), frontal lobe ( β  = 0.237; p = 0.043), and parietal lobe ( β = 0.265; p = 0.024) were significantly linked to higher plasma Aβ1-42/Aβ1-40 ratios, after above adjustments.

CONCLUSION

BBB leakage is a common feature of DLB and possibly is even more severe than in the setting of AD for certain regions of the brain. BBB leakage appears to correlate with plasma Aβ1-42/Aβ1-40 ratio and dementia severity.

Associations Between Neuropsychiatric Symptoms and Inflammation in Neurodegenerative Dementia: A Systematic Review

Background

Neuropsychiatric symptoms are common in dementia and linked to adverse outcomes. Inflammation is increasingly recognized as playing a role as a driver of early disease progression in Alzheimer's disease (AD) and related dementias. Inflammation has also been linked to primary psychiatric disorders, however its association with neuropsychiatric symptoms in neurodegenerative dementias remains uncertain.

Methods

We conducted a systematic literature review investigating associations between inflammation and neuropsychiatric symptoms in neurodegenerative dementias, including AD, Lewy body, Frontotemporal, Parkinson's (PD) and Huntington's disease dementias.

Results

Ninety-nine studies met our inclusion criteria, and the majority (n = 59) investigated AD and/or mild cognitive impairment (MCI). Thirty-five studies included PD, and only 6 investigated non-AD dementias. Inflammation was measured in blood, CSF, by genotype, brain tissue and PET imaging. Overall, studies exhibited considerable heterogeneity and evidence for specific inflammatory markers was inconsistent, with lack of replication and few longitudinal studies with repeat biomarkers. Depression was the most frequently investigated symptom. In AD, some studies reported increases in peripheral IL-6, TNF-a associated with depressive symptoms. Preliminary investigations using PET measures of microglial activation found an association with agitation. In PD, studies reported positive associations between TNF-a, IL-6, CRP, MCP-1, IL-10 and depression.

Conclusion

Central and peripheral inflammation may play a role in neuropsychiatric symptoms in neurodegenerative dementias; however, the evidence is inconsistent. There is a need for multi-site longitudinal studies with detailed assessments of neuropsychiatric symptoms combined with replicable peripheral and central markers of inflammation.

EEG Functional Connectivity Differences Predict Future Conversion to Dementia in Mild Cognitive Impairment With Lewy Body or Alzheimer Disease

BACKGROUND

Predicting which individuals may convert to dementia from mild cognitive impairment (MCI) remains difficult in clinical practice. Electroencephalography (EEG) is a widely available investigation but there is limited research exploring EEG connectivity differences in patients with MCI who convert to dementia.

METHODS

Participants with a diagnosis of MCI due to Alzheimer's disease (MCI-AD) or Lewy body disease (MCI-LB) underwent resting state EEG recording. They were followed up annually with a review of the clinical diagnosis (n = 66). Participants with a diagnosis of dementia at year 1 or year 2 follow up were classed as converters (n = 23) and those with a diagnosis of MCI at year 2 were classed as stable (n = 43). We used phase lag index (PLI) to estimate functional connectivity as well as analysing dominant frequency (DF) and relative band power. The Network-based statistic (NBS) toolbox was used to assess differences in network topology.

RESULTS

The converting group had reduced DF (U = 285.5, p = 0.005) and increased relative pre-alpha power (U = 702, p = 0.005) consistent with previous findings. PLI showed reduced average beta band synchrony in the converting group (U = 311, p = 0.014) as well as significant differences in alpha and beta network topology. Logistic regression models using regional beta PLI values revealed that right central to right lateral (Sens = 56.5%, Spec = 86.0%, -2LL = 72.48, p = 0.017) and left central to right lateral (Sens = 47.8%, Spec = 81.4%, -2LL = 71.37, p = 0.012) had the best classification accuracy and fit when adjusted for age and MMSE score.

CONCLUSION

Patients with MCI who convert to dementia have significant differences in EEG frequency, average connectivity and network topology prior to the onset of dementia. The MCI group is clinically heterogeneous and have underlying physiological differences that may be driving the progression of cognitive symptoms. EEG connectivity could be useful to predict which patients with MCI-AD and MCI-LB convert to dementia, regardless of the neurodegenerative aetiology.

Is Montreal Cognitive Assessment a valuable test for the differentiation of Alzheimer's disease, frontotemporal dementia, dementia with Lewy body, and vascular dementia?

Dementia is one of the growing diseases in the world and has different types based on its definition. The Montreal Cognitive Assessment (MoCA) test has been employed to screen patients with dementia, cognitive impairment, and disruption of daily activities.

Objective

This study examined the diagnostic value of the total MoCA score and its subscores in differentiating Alzheimer's disease (AD), frontotemporal dementia (FTD), dementia with Lewy body (DLB), and vascular dementia (VaD).

Methods

A total of 241 patients (AD=110, FTD=90, DLB=28, and VaD=13) and 59 healthy persons, who were referred to a dementia clinic with memory impairment in Firoozgar Hospital, were included in this study. MoCA tests were performed in all patients and normal persons.

Results

By using the receiver operating characteristic (ROC) curve and measuring the area under the curve (AUC) for the total MoCA score in each group, AUC was 0.616, 0.681, 0.6117, and 0.583 for differentiating AD, FTD, DLB, and VaD patients, respectively. Among the groups, just the VaD group showed no significant usefulness in using the total MoCA score to differentiate it. To compare MoCA subscores, AD patients had higher scores in digit span, literal fluency, and abstraction but lower delayed recall scores compared with FTD patients.

Conclusion

The total MoCA score and its subscores could not differentiate people with different types of dementia in the setting of screening.

The Role of α-Synuclein in Etiology of Neurodegenerative Diseases

A presynaptic protein called α-synuclein plays a crucial role in synaptic function and neurotransmitter release. However, its misfolding and aggregation have been implicated in a variety of neurodegenerative diseases, particularly Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy. Emerging evidence suggests that α-synuclein interacts with various cellular pathways, including mitochondrial dysfunction, oxidative stress, and neuroinflammation, which contributes to neuronal cell death. Moreover, α-synuclein has been involved in the propagation of neurodegenerative processes through prion-like mechanisms, where misfolded proteins induce similar conformational changes in neighboring neurons. Understanding the multifaced roles of α-synuclein in neurodegeneration not only aids in acquiring more knowledge about the pathophysiology of these diseases but also highlights potential biomarkers and therapeutic targets for intervention in alpha-synucleinopathies. In this review, we provide a summary of the mechanisms by which α-synuclein contributes to neurodegenerative processes, focusing on its misfolding, oligomerization, and the formation of insoluble fibrils that form characteristic Lewy bodies. Furthermore, we compare the potential value of α-synuclein species in diagnosing and differentiating selected neurodegenerative diseases.

Factors Associated With Increased Health Care Utilization for Patients With Dementia With Lewy Bodies: A Narrative Review

Numerous studies have demonstrated that dementia is associated with increased utilization of health care services, which in turn results in increased costs of care. Dementia with Lewy bodies (DLB) is associated with greater costs of care relative to other forms of dementia due to higher rates of hospitalization and nursing home placement directly related to neuropsychiatric symptoms, parkinsonism, increased susceptibility to delirium, and elevated rates of caregiver burden. There is a critical need for researchers to identify potentially modifiable factors contributing to increased costs of care and poor clinical outcomes for patients with DLB, which may include comorbidities, polypharmacy/contraindicated medications, and access to specialty care. Previous research has utilized Medicare claims data, limiting the ability to study patients with early-onset (ie, prior to age 65) DLB. Integrated health systems offer the ability to combine electronic medical record data with Medicare, Medicaid, and commercial claims data and may therefore be ideal for utilization research in this population. The goals of this narrative review are to 1) synthesize and describe the current literature on health care utilization studies for patients with DLB, 2) highlight the current gaps in the literature, and 3) provide recommendations for stakeholders, including researchers, health systems, and policymakers. It is important to improve current understanding of potentially modifiable factors associated with increased costs of care among patients with DLB to inform public health policies and clinical decision-making, as this will ultimately improve the quality of patient care.

Role of Amyloidogenic and Non-Amyloidogenic Protein Spaces in Neurodegenerative Diseases and their Mitigation Using Theranostic Agents

Neurodegenerative diseases (NDDs) refer to a complex heterogeneous group of diseases which are associated with the accumulation of amyloid fibrils or plaques in the brain leading to progressive loss of neuronal functions. Alzheimer's disease is one of the major NDD responsible for 60-80 % of all dementia cases. Currently, there are no curative or disease-reversing/modifying molecules for many of the NDDs except a few such as donepezil, rivastigmine, galantamine, carbidopa and levodopa which treat the disease-associated symptoms. Similarly, there are very few FDA-approved tracers such as flortaucipir (Tauvid) for tau fibril imaging and florbetaben (Neuraceq), flutemetamol (Vizamyl), and florbetapir (Amyvid) for amyloid imaging available for diagnosis. Recent advances in the cryogenic electron microscopy reported distinctly different microstructures for tau fibrils associated with different tauopathies highlighting the possibility to develop tauopathy-specific imaging agents and therapeutics. In addition, it is important to identify the proteins that are associated with disease development and progression to know about their 3D structure to develop various diagnostics, therapeutics and theranostic agents. The current article discusses in detail the disease-associated amyloid and non-amyloid proteins along with their structural insights. We comprehensively discussed various novel proteins associated with NDDs and their implications in disease pathology. In addition, we document various emerging chemical compounds developed for diagnosis and therapy of different NDDs with special emphasis on theranostic agents for better management of NDDs.

Near-Infrared Ratiometric Fluorescent Probe for Detecting Endogenous Cu2+ in the Brain

Copper participates in a range of critical functions in the nervous system and human brain. Disturbances in brain copper content is strongly associated with neurological diseases. For example, changes in the level and distribution of copper are reported in neuroblastoma, Alzheimer's disease, and Lewy body disorders, such as Parkinson disease and dementia with Lewy bodies (DLB). There is a need for more sensitive techniques to measure intracellular copper levels to have a better understanding of the role of copper homeostasis in neuronal disorders. Here, we report a reaction-based near-infrared (NIR) ratiometric fluorescent probe CyCu1 for imaging Cu2+ in biological samples. High stability and selectivity of CyCu1 enabled the probe to be deployed as a sensor in a range of systems, including SH-SY5Y cells and neuroblastoma tumors. Furthermore, it can be used in plant cells, reporting on copper added to Arabidopsis roots. We also used CyCu1 to explore Cu2+ levels and distribution in post-mortem brain tissues from patients with DLB. We found significant decreases in Cu2+ content in the cytoplasm, neurons, and extraneuronal space in the degenerating substantia nigra in DLB compared with healthy age-matched control tissues. These findings enhance our understanding of Cu2+ dysregulation in Lewy body disorders. Our probe also shows promise as a photoacoustic imaging agent, with potential for applications in bimodal imaging.

Causal effects for neurodegenerative diseases on the risk of myocardial infarction: a two-sample Mendelian randomization study

Several studies have demonstrated a correlation between neurodegenerative diseases (NDDs) and myocardial infarction (MI), yet the precise causal relationship between these remains elusive. This study aimed to investigate the potential causal associations of genetically predicted Alzheimer's disease (AD), dementia with Lewy bodies (DLB), Parkinson's disease (PD), and multiple sclerosis (MS) with MI using two-sample Mendelian randomization (TSMR). Various methods, including inverse variance weighted (IVW), weighted median (WM), MR-Egger regression, weighted mode, and simple mode, were employed to estimate the effects of genetically predicted NDDs on MI. To validate the analysis, we assessed pleiotropic effects, heterogeneity, and conducted leave-one-out sensitivity analysis. We identified that genetic predisposition to NDDs was suggestively associated with higher odds of MI (OR_IVW=1.07, OR_MR-Egger=1.08, OR_WM=1.07, OR_weighted mode=1.07, OR_simple mode=1.10, all P<0.05). Furthermore, we observed significant associations of genetically predicted DLB with MI (OR_IVW=1.07, OR_MR-Egger=1.11, OR_WM=1.09, OR_weighted mode=1.09, all P<0.05). However, there was no significant causal evidence of genetically predicted PD and MS in MI. Across all MR analyses, no horizontal pleiotropy or statistical heterogeneity was observed (all P>0.05). Additionally, results from MRPRESSO and leave-one-out sensitivity analysis confirmed the robustness of the causal effect estimations for genetically predicted AD, DLB, PD, and MS on MI. This study provides further support for the causal effects of AD on MI and, for the first time, establishes robust causal evidence for the detrimental effect of DLB on the risk of MI. Our findings emphasize the importance of monitoring the cardiovascular function of the elderly experiencing neurodegenerative changes.

Cognitive Impairment in the Primary Care Clinic

Cognitive impairment is a common problem in the geriatric population and is characterized by variable symptoms of memory difficulties, executive dysfunction, language or visuospatial problems, and behavioral changes. It is imperative that primary care clinicians recognize and differentiate the variable symptoms associated with cognitive impairment from changes attributable to normal aging or secondary to other medical conditions. A thorough evaluation for potentially reversible causes of dementia is required before diagnosis with a neurodegenerative dementia. Other abnormal neurologic findings, rapid progression, or early age of onset are red flags that merit referral to neurology for more specialized evaluation and treatment.