Diagnosis and management of dementia with Lewy bodies: Fourth consensus report of the DLB Consortium

Relevance of 123I-FP-CIT SPECT prescriptions for the diagnosis of parkinsonian syndromes

123I-FP-CIT SPECT enables the detection of presynaptic dopaminergic denervation. It allows to differentiate degenerative parkinsonian syndromes from secondary parkinsonian syndromes or essential tremor, and patients with suspected dementia with Lewy bodies from those with other dementia subtypes. The aim of our study was to evaluate the appropriateness of 123I-FP-CIT SPECT prescriptions, identify prescriber profiles and analyze changes in prescriptions over a decade in the Neurology department of Avicenne University hospital. This retrospective study included all patients who underwent 123I-FP-CIT SPECT between February 2009 and May 2019 (n = 723). Clinical and paraclinical data were compared between three groups based on the relevance of 123I-FP-CIT SPECT prescription: "inappropriate", "uncertain" and "relevant". We showed that inappropriate indications accounted for 37.5% of 123I-FP-CIT SPECT requests. Hospital neurologists and neurologists with mixed practice accounted for 74.1% of 123I-FP-CIT SPECT requests, hospital movement disorders specialists being more likely to prescribe appropriately (67.1%) than hospital non-movement disorders specialists (33.3%). Following the replacement of the neuro-oncology team with a team including movement disorders specialists, the percentage of relevant SPECT 123I-FP-CIT prescriptions rose from 37.5% to 81.0%. These observations suggest that seeking the expertise of a movement disorders specialist would be more relevant than the systematic prescription of 123I-FP-CIT SPECT.

α-synuclein seed amplification assay sensitivity may be associated with cardiac MIBG abnormality among patients with Lewy body disease

Although α-synuclein seed amplification assays (α-syn SAA) are promising, its sensitivity may be affected by heterogeneity among patients with Lewy body disease (LBD). We evaluated whether α-syn SAA sensitivity is affected by patient heterogeneity, using 123I-meta-iodobenzylguanidine (MIBG) cardiac scintigraphy in early drug-naïve patients. Thirty-four patients with clinically established or probable Parkinson's disease (PD) and seven with dementia with Lewy bodies (DLB) or prodromal DLB were included. While 85.2% of patients with abnormal cardiac MIBG were α-syn SAA positive, only 14.3% were positive among those with normal scans. Logistic regression analysis showed that MIBG positivity was the only significant variable associated with α-syn SAA positivity (odds ratio 74.2 [95% confidence interval 6.1-909]). Although α-syn SAA is sensitive for LBD in patients with abnormal MIBG, the sensitivity may be lower in those with normal MIBG. Further studies are necessary to evaluate the association between patient heterogeneity and α-syn SAA sensitivity.

Multi-Class Detection of Neurodegenerative Diseases from EEG Signals Using Lightweight LSTM Neural Networks

Neurodegenerative diseases severely impact the life of millions of patients worldwide, and their occurrence is more and more increasing proportionally to longer life expectancy. Electroencephalography has become an important diagnostic tool for these diseases, due to its relatively simple procedure, but it requires analyzing a large number of data, often carrying a small fraction of informative content. For this reason, machine learning tools have gained a considerable relevance as an aid to classify potential signs of a specific disease, especially in its early stages, when treatments can be more effective. In this work, long short-term memory-based neural networks with different numbers of units were properly designed and trained after accurate data pre-processing, in order to perform a multi-class detection. To this end, a custom dataset of EEG recordings from subjects affected by five neurodegenerative diseases (Alzheimer's disease, frontotemporal dementia, dementia with Lewy bodies, progressive supranuclear palsy, and vascular dementia) was acquired. Experimental results show that an accuracy up to 98% was achieved with data belonging to different classes of disease, up to six including the control group, while not requiring particularly heavy computational resources.

Plasma neurofilament light chain as prognostic marker of cognitive decline in neurodegenerative diseases, a clinical setting study

BACKGROUND

Analysis of selected research cohorts has highlighted an association between plasma neurofilament light (NfL) protein and cross-sectional cognitive impairment as well as longitudinal cognitive decline. However, the findings have yielded inconsistent results regarding its possible application in clinical practice. Despite its potential prognostic significance, the role of plasma NfL in daily clinical practice with unselected patients suffering from cognitive impairment remains largely unexplored.

METHODS

This retrospective, cross-sectional and longitudinal monocentric study enrolled 320 patients with Alzheimer's disease ([AD], n = 158), dementia with Lewy body ([DLB], n = 30), frontotemporal dementia ([FTD], n = 32), non-neurodegenerative diseases ([NND], n = 59) or subjective cognitive decline ([SCD], n = 41). Plasma NfL levels were measured at baseline on the Simoa platform. AD, DLB, and FTD patients were also analyzed altogether as a 'degenerative conditions' subgroup, whereas SCD and NND were grouped as a 'non-degenerative conditions' subgroup. We assessed the relationship between plasma NfL levels and cross-sectional cognitive performance, including global cognition and six specific cognitive domains. A subset of 239 patients had follow-up mini-mental state examinations (MMSE) up to 60 months. Models were adjusted on age, education level, glomerular filtration rate and body mass index.

RESULTS

In 320 patients, baseline plasma NfL levels were negatively associated with global cognition (β=-1.28 (-1.81 ; -0.75) P < 0.001), memory (β=-1.48 (-2.38 ; -0.59), P = 0.001), language (β=-1.72(-2.49 ; -0.95) P < 0.001), praxis (β=-2.02 (-2.91 ; -1.13) P < 0.001) and executive functions (β=-0.81, P < 0.001). Across diagnosis, plasma NfL levels were negatively associated with cross-sectional global cognition in all but the SCD subgroup, specifically with executive functions and memory in AD (respectively β=-0.71(-1.21 ; -0.211), P = 0.005 and β=-1.29 (-2.17 ; -0.42), P = 0.004), and with attention in LBD (β=-0.81(-1.16 ; -0.002), P = 0.03). Linear mixed-effects models showed that plasma NfL predicted MMSE decline in the global population (βPlasmaNfLxTime=-0.15 (-0.26 ; -0.04), P = 0.006), as in the neurodegenerative condition subgroup (βPlasmaNfLxTime=-0.21 (-0.37 ; - 0.06), P = 0.007), but not in non-neurodegenerative condition subgroup.

CONCLUSION

In our clinical cohort, plasma NfL was associated with faster cognitive decline in neurodegenerative dementia, which corroborates data obtained in research cohorts. Yet, plasma NfL was not predictive of accelerated cognitive decline in individuals without neurodegeneration, suggesting its use as a neurodegeneration-specific predictive biomarker.

SNMMI Procedure Standard/EANM Practice Guideline for Brain [18F]FDG PET Imaging, Version 2.0

PREAMBLEThe Society of Nuclear Medicine and Molecular Imaging (SNMMI) is an international scientific and professional organization founded in 1954 to promote the science, technology, and practical application of nuclear medicine. The European Association of Nuclear Medicine (EANM) is a professional nonprofit medical association that facilitates communication worldwide between individuals pursuing clinical and research excellence in nuclear medicine. The EANM was founded in 1985. The EANM was founded in 1985. SNMMI and EANM members are physicians, technologists, and scientists specializing in the research and practice of nuclear medicine.The SNMMI and EANM will periodically define new guidelines for nuclear medicine practice to help advance the science of nuclear medicine and to improve the quality of service to patients throughout the world. Existing practice guidelines will be reviewed for revision or renewal, as appropriate, on their fifth anniversary or sooner, if indicated.Each practice guideline, representing a policy statement by the SNMMI/EANM, has undergone a thorough consensus process in which it has been subjected to extensive review. The SNMMI and EANM recognize that the safe and effective use of diagnostic nuclear medicine imaging requires specific training, skills, and techniques, as described in each document. Reproduction or modification of the published practice guideline by those entities not providing these services is not authorized.These guidelines are an educational tool designed to assist practitioners in providing appropriate care for patients. They are not inflexible rules or requirements of practice and are not intended, nor should they be used, to establish a legal standard of care. For these reasons and those set forth below, both the SNMMI and the EANM caution against the use of these guidelines in litigation in which the clinical decisions of a practitioner are called into question.The ultimate judgment regarding the propriety of any specific procedure or course of action must be made by the physician or medical physicist in light of all the circumstances presented. Thus, there is no implication that an approach differing from the guidelines, standing alone, is below the standard of care. To the contrary, a conscientious practitioner may responsibly adopt a course of action different from that set forth in the guidelines when, in the reasonable judgment of the practitioner, such course of action is indicated by the condition of the patient, limitations of available resources, or advances in knowledge or technology subsequent to publication of the guidelines.The practice of medicine includes both the art and the science of the prevention, diagnosis, alleviation, and treatment of disease. The variety and complexity of human conditions make it impossible to always reach the most appropriate diagnosis or to predict with certainty a particular response to treatment.Therefore, it should be recognized that adherence to these guidelines will not ensure an accurate diagnosis or a successful outcome. All that should be expected is that the practitioner will follow a reasonable course of action based on current knowledge, available resources, and the needs of the patient to deliver effective and safe medical care. The sole purpose of these guidelines is to assist practitioners in achieving this objective.

Substantia nigra hyperechogenicity and brain ventricular size as biomarkers of early dementia with Lewy bodies

BACKGROUND

Diagnosis of dementia with Lewy bodies (DLB) is challenging, especially in the earlier stages of the disease, owing to the clinical overlap with other neurodegenerative diseases such as Alzheimer's (AD) and Parkinson's disease (PD). We aimed to identify the transcranial sonography (TCS) parameters that can help us to detect early DLB patients.

METHODS

In this cross-sectional study, we prospectively recruited newly diagnosed DLB patients with less than 3 years from the onset of cognitive symptoms. For comparison purposes, we also included AD and PD patients, with a disease duration of less than 3 years, and a control group. TCS was performed to assess the substantia nigra (SN) echogenicity, the width of the third ventricle, and the frontal horns of the lateral ventricles. Subsequently, TCS images were analyzed with the medical image viewer Horos in order to quantify the intensity of the echogenicity of the SN. Univariate analysis and a logistic regression model were used to identify which variables can predict the diagnosis of DLB.

RESULTS

One hundred and seven participants were included (23 DLB, 26 AD, 27 PD and 31 controls). The median age of DLB patients was 75(72-77) years, with a disease duration of 2 years. DLB and PD patients showed higher SN hyperechogenicity rates (72.73% and 81.82%, respectively) and a greater area of the SN compared to AD patients and controls (p < 0.001). DLB and AD patients had wider ventricular systems than the other study groups. The SN hyperechogenicity predicted a diagnosis of DLB with an odds ratio of 22.67 (95%CI 3.98; 129.12, p < 0.001) when compared to AD patients. Unilateral and bilateral widened frontal horns predicted diagnosis of DLB compared to PD with an odds ratio of 9.5 (95%CI 0.97; 92.83, p = 0.053) and 5.7 (95%CI 0.97; 33.6, p = 0.054), respectively.

CONCLUSIONS

Echogenicity of the SN and widening of the frontal horns of lateral ventricles can predict the diagnosis of early DLB in this cohort of newly diagnosed patients, when compared to AD and PD patients. Transcranial sonography, a non-invasive tool, could be helpful for the diagnosis of DLB at its earlier stages.

Plasma lipidomic signatures of dementia with Lewy bodies revealed by machine learning, and compared to alzheimer's disease

BACKGROUND

Dementia with Lewy Bodies (DLB) is a complex neurodegenerative disorder that often overlaps clinically with Alzheimer's disease (AD), presenting challenges in accurate diagnosis and underscoring the need for novel biomarkers. Lipidomic emerges as a promising avenue for uncovering disease-specific metabolic alterations and potential biomarkers, particularly as the lipidomics landscape of DLB has not been previously explored. We aim to identify potential diagnostic biomarkers and elucidate the disease's pathophysiological mechanisms.

METHODS

This study conducted a lipidomic analysis of plasma samples from patients with DLB, AD, and healthy controls (HCs) at Xuanwu Hospital. Untargeted plasma lipidomic profiling was conducted via liquid chromatography coupled with mass spectrometry. Machine learning methods were employed to discern lipidomic signatures specific to DLB and to differentiate it from AD.

RESULTS

The study enrolled 159 participants, including 57 with AD, 48 with DLB, and 54 HCs. Significant differences in lipid profiles were observed between the DLB and HC groups, particularly in the classes of sphingolipids and phospholipids. A total of 55 differentially expressed lipid species were identified between DLB and HCs, and 17 between DLB and AD. Correlations were observed linking these lipidomic profiles to clinical parameters like Unified Parkinson's Disease Rating Scale III (UPDRS III) and cognitive scores. Machine learning models demonstrated to be highly effective in distinguishing DLB from both HCs and AD, achieving substantial accuracy through the utilization of specific lipidomic signatures. These include PC(15:0_18:2), PC(15:0_20:5), and SPH(d16:0) for differentiation between DLB and HCs; and a panel includes 13 lipid molecules: four PCs, two PEs, three SPHs, two Cers, and two Hex1Cers for distinguishing DLB from AD.

CONCLUSIONS

This study presents a novel and comprehensive lipidomic profile of DLB, distinguishing it from AD and HCs. Predominantly, sphingolipids (e.g., ceramides and SPHs) and phospholipids (e.g., PE and PC) were the most dysregulated lipids in relation to DLB patients. The lipidomics panels identified through machine learning may serve as effective plasma biomarkers for diagnosing DLB and differentiating it from AD dementia.

Pathologic subtyping of Alzheimer's disease brain tissue reveals disease heterogeneity

In recent years, multiple groups have shown that what is currently thought of as "Alzheimer's Disease" (AD) may be usefully viewed as several related disease subtypes. As these efforts have continued, a related issue is how common co-pathologies and ethnicity intersect with AD subtypes. The goal of this study was to use a dataset constituting 153 pathologic variables recorded on 666 AD brain autopsies to better define how co-pathologies and ethnicity relate to established AD subtypes. Pathologic clustering suggests 8 subtypes within this cohort, and further analysis reveals that the previously described continuum from hippocampal predominant to hippocampal sparing is well represented in our data. Small vessel disease is overall highest in a cluster with a low hippocampal/cortical tau ratio, and across all clusters small vessel disease segregates separately from Lewy body disease. Two AD clusters are identified with extensive Lewy bodies outside amygdala (one with a high hippocampal/cortical tau ratio and one with a low ratio), and we find an inverse relationship between cortical tau and Lewy body pathology across these two clusters. Finally, we find that brains from persons of Hispanic descent have significantly more AD pathology in multiple neuroanatomic areas. We find that Hispanic ethnicity is not uniformly distributed across clusters, and this is particularly pronounced in clusters with significant Lewy body pathology, where Hispanic donors are only found in a cluster with a low hippocampal/cortical tau ratio. In summary, our analysis of recorded pathologic data across two decades of banked brains reveals new relationships in the patterns of AD-related proteinopathy, co-pathology, and ethnicity, and highlights the utility of pathologic subtyping to classify AD pathology.

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.

Unpacking unstructured data: A pilot study on extracting insights from neuropathological reports of Parkinson's Disease patients using large language models

The aim of this study was to make unstructured neuropathological data, located in the NeuroBioBank (NBB), follow Findability, Accessibility, Interoperability, and Reusability principles and investigate the potential of large language models (LLMs) in wrangling unstructured neuropathological reports. By making the currently inconsistent and disparate data findable, our overarching goal was to enhance research output and speed. The NBB catalog currently includes information from medical records, interview results, and neuropathological reports. These reports contain crucial information necessary for conducting an in-depth analysis of NBB data but have multiple formats that vary across different NBB biorepositories and change over time. In this study, we focused on a subset of 822 donors with Parkinson's disease (PD) from seven NBB biorepositories. We developed a data model with combined Brain Region and Pathological Findings data at its core. This approach made it easier to build an extraction pipeline and was flexible enough to convert resulting data to Common Data Elements, a standardized data collection tool used by the neuroscience community to improve consistency and facilitate data sharing across studies. This pilot study demonstrated the potential of LLMs in structuring unstructured neuropathological reports of PD patients available in the NBB. The pipeline enabled successful extraction of detailed tissue-level (microscopic) and gross anatomical (macroscopic) observations, along with staging information from pathology reports, with extraction quality comparable to manual curation results. To our knowledge, this is the first attempt to automatically standardize neuropathological information at this scale. The collected data have the potential to serve as a valuable resource for PD researchers, facilitating integration with clinical information and genetic data (such as genome-wide genotyping and whole-genome sequencing) available through the NBB, thereby enabling a more comprehensive understanding of the disease.

Current Perspectives on Olfactory Loss in Atypical Parkinsonisms-A Review Article

INTRODUCTION

Atypical parkinsonisms (APs) present various symptoms including motor impairment, cognitive decline, and autonomic dysfunction. Olfactory loss (OL), being a significant non-motor symptom, has emerged as an under-evaluated, yet potentially valuable, feature that might aid in the differential diagnosis of APs.

STATE OF THE ART

The most pronounced OL is usually associated with Dementia with Lewy Bodies (DLB). While the view about the normosmic course of Multiple System Atrophy (MSA) remains unchanged, research indicates that mild OL may occur in a subset of patients with Progressive Supranuclear Palsy (PSP) and Corticobasal Degeneration (CBD). This might be linked to the deposition of abnormal protein aggregates in the central nervous system.

CLINICAL SIGNIFICANCE

The aim of this review is to discuss the role of OL and its degree and pattern in the pathogenesis and course of APs. Olfactory testing could serve as a non-invasive, quick screening tool to differentiate between APs and project disease progression.

FUTURE DIRECTIONS

There is a need for further evaluation of this topic. This may lead to the development of standardized olfactory testing protocols that could be implemented in clinical practice, making differential diagnosis of APs more convenient. Understanding differences in the sense of smell could create an avenue for more targeted therapeutic strategies.

Clinical and diagnostic implications of Alzheimer's disease copathology in Lewy body disease

Concomitant Alzheimer's disease (AD) pathology is a frequent event in the context of Lewy body disease (LBD), occurring in approximately half of all cases. Evidence shows that LBD patients with AD copathology show an accelerated disease course, a greater risk of cognitive decline and an overall poorer prognosis. However, LBD-AD cases may show heterogeneous motor and non-motor phenotypes with a higher risk of dementia and, consequently, be not rarely misdiagnosed. In this review, we summarize the current understanding of LBD-AD by discussing the synergistic effects of AD neuropathological changes and Lewy pathology and their clinical relevance. Furthermore, we provide an extensive overview of neuroimaging and fluid biomarkers under assessment for use in LBD-AD and their possible diagnostic and prognostic values. AD pathology can be predicted in vivo by means of CSF, MRI and PET markers, whereas the most promising technique to date for identifying Lewy pathology in different biological tissues is the α-synuclein seed amplification assay. Pathological imaging and CSF AD biomarkers are associated with a higher likelihood of cognitive decline in LBD but do not always mirror the neuropathological severity as in pure AD. Implementing the use of blood-based AD biomarkers might allow faster screening of LBD patients for AD copathology, thus improving the overall diagnostic sensitivity for LBD-AD. Finally, we discuss the literature on novel candidate biomarkers being exploited in LBD-AD to investigate other aspects of neurodegeneration, such as neuroaxonal injury, glial activation and synaptic dysfunction. The thorough characterization of AD copathology in LBD should be taken into account when considering differential diagnoses of dementia syndromes, to allow prognostic evaluation on an individual level, and to guide symptomatic and disease-modifying therapies.

Connecting dementia risk loci to the CSF proteome identifies pathophysiological leads for dementia

Genome-wide association studies have successfully identified many genetic risk loci for dementia, but exact biological mechanisms through which genetic risk factors contribute to dementia remains unclear. Integrating CSF proteomic data with dementia risk loci could reveal intermediate molecular pathways connecting genetic variance to the development of dementia. We tested to what extent effects of known dementia risk loci can be observed in CSF levels of 665 proteins [proximity extension-based (PEA) immunoassays] in a deeply-phenotyped mixed memory clinic cohort [n = 502, mean age (standard deviation, SD) = 64.1 (8.7) years, 181 female (35.4%)], including patients with Alzheimer's disease (AD, n = 213), dementia with Lewy bodies (DLB, n = 50) and frontotemporal dementia (FTD, n = 93), and controls (n = 146). Validation was assessed in independent cohorts (n = 99 PEA platform, n = 198, mass reaction monitoring-targeted mass spectroscopy and multiplex assay). We performed additional analyses stratified according to diagnostic status (AD, DLB, FTD and controls separately), to explore whether associations between CSF proteins and genetic variants were specific to disease or not. We identified four AD risk loci as protein quantitative trait loci (pQTL): CR1-CR2 (rs3818361, P = 1.65 × 10-8), ZCWPW1-PILRB (rs1476679, P = 2.73 × 10-32), CTSH-CTSH (rs3784539, P = 2.88 × 10-24) and HESX1-RETN (rs186108507, P = 8.39 × 10-8), of which the first three pQTLs showed direct replication in the independent cohorts. We identified one AD-specific association between a rare genetic variant of TREM2 and CSF IL6 levels (rs75932628, P = 3.90 × 10-7). DLB risk locus GBA showed positive trans effects on seven inter-related CSF levels in DLB patients only. No pQTLs were identified for FTD loci, either for the total sample as for analyses performed within FTD only. Protein QTL variants were involved in the immune system, highlighting the importance of this system in the pathophysiology of dementia. We further identified pQTLs in stratified analyses for AD and DLB, hinting at disease-specific pQTLs in dementia. Dissecting the contribution of risk loci to neurobiological processes aids in understanding disease mechanisms underlying dementia.

[Psychopathology of Lewy body disease: the clinical benefits of early detection]

Despite its high prevalence among neurodegenerative diseases, Lewy body disease (LBD), or Lewy body dementia (LBD), because of its clinical proximity to Alzheimer's and Parkinson's diseases, is often undiagnosed or misdiagnosed. Better identification of this condition, in order to provide better care for sufferers and their carers, is a health objective on which progress is desirable.

Long-term effects of cholinesterase inhibitors and memantine on cognitive decline, cardiovascular events, and mortality in dementia with Lewy bodies: An up to 10-year follow-up study

INTRODUCTION

We aimed to assess the impact of cholinesterase inhibitors (ChEIs) and memantine on cognition, major adverse cardiovascular events (MACE) and mortality in dementia with Lewy bodies (DLB).

METHODS

A total of 1,095 incident DLB patients from the Swedish Registry on cognitive/dementia disorders were included. Using an inverse probability of treatment weighting, the effect of initiating ChEI or memantine within 90 days of DLB diagnosis and nonuse was evaluated on cognitive trajectories and risks of MACE and death.

RESULTS

The use of ChEIs significantly slowed cognitive decline at follow-ups (Mini-Mental State Examination [MMSE] -0.39 points/y; 95% confidence interval [CI], -0.96 to 0.18) compared to memantine (-2.49 points/y; -4.02 to -0.97) and nonuse (-2.50 points/y; -4.28 to -0.73). Treatment groups did not differ in MACE events. ChEI use was associated with lower risk of death in the first year after DLB diagnosis (adjusted hazard ratio [HR] 0.66, 95% CI 0.46, 0.94).

DISCUSSION

Our findings illuminate the potential benefits of ChEI treatment in DLB patients.

HIGHLIGHTS

Cholinesterase inhibitors slow cognitive decline over a 5-year follow-up period when compared to both memantine treatment and nonuse in patients with dementia with Lewy bodies. Cholinesterase Inhibitors reduce risk of mortality within the initial year, but this effect is not sustained after 1 year in patients with dementia with Lewy bodies.

Wheelchair dependence in patients with dementia: Focus on kinematic gait analysis using simple wearable accelerometers and gyroscopes

Falls, wheelchair dependence, and bedridden status are the results of reduced mobility in the mid-late course of dementia. Kinematic gait analysis for patients with dementia is lacking because practically setting sensors on their bodies is particularly difficult. We analyzed the parameters of kinematic gait analysis that are related to the risks of wheelchair dependence in patients with dementia using wearable accelerometers and gyroscopes for detecting 3-dimensional physical movements. We collected data from 34 patients with dementia regarding demographics, cognitive function, CT scan findings, medications, and gait analysis parameters. The patients were followed up for 6 months. We compared data between dementia patients with and without wheelchair dependence by t-test or Fisher's exact test, multiple comparison, and simple logistic regression analysis for wheelchair dependence by gait analysis parameters. Eleven patients became wheelchair-dependent during the 6 months. The score on the clinical dementia rating scale was significantly higher and the hip extensor angle in walking was significantly lower in patients with dementia with wheelchair dependence than in those without. The severity of dementia and the lower angle of the hip extensor during walking may indicate the necessity of a wheelchair for patients with this disease.

Neuropsychological Determinants of Impairment in Activities of Daily Living in Patients With Lewy Body Dementia

Background Understanding the specific cognitive domains associated with activities of daily living (ADLs) impairment in Lewy body dementia (LBD) may help identify which targeted therapeutic interventions to pursue in future research. This study aimed to investigate the neuropsychological determinants of impairment in ADLs in LBD patients. Methods We conducted a cross-sectional study of LBD patients referred for a clinical neuropsychological evaluation within the Parkinson's Disease and Movement Disorders Center at Virginia Commonwealth University. The presence or absence of impairment in eight ADLs and neuropsychological test performances were collected and analyzed. Cluster analysis and hierarchical analysis were used to define ADL impairment into mild, moderate, and severe ADL impairment groups. We then compared cognitive performance between the ADL groups. Results This study included 193 LBD patients. Compared to LBD patients with mild and moderate ADL impairment, those with severe ADL impairment had worse scores in global cognition as measured by the Dementia Rating Scale-2 (DRS-2) (p=0.002), speeded visuospatial processing as measured by the Trail Making Test A (p=0.001), speeded executive functioning as measured by the Trail Making Test B (p=0.006), and psychomotor processing speed (p<0.001). Impairments in driving and self-care were associated with worse performances on Trail Making Test A, Trail Making Test B, and psychomotor processing speed (all p<0.05). Conclusions In patients with LBD, impaired speeded tasks of visual processing and executive functioning are associated with impaired ADLs, particularly driving and self-care. In order to improve ADLs in LBD, future studies should focus on identifying therapies that improve processing speed performance.

Correlation between dopaminergic and metabolic asymmetry in Lewy body disease - A dual-imaging study

INTRODUCTION

The a-Synuclein Origin and Connectome (SOC) model of Lewy body diseases postulates that a-syuclein will be asymmetrically distributed in some patients with Lewy body diseases, potentially leading to asymmetric neuronal dysfunction and symptoms.

METHODS

We included two patient groups: 19 non-demented Parkinson's disease (nPD) patients with [18F]FDG PET and motor symptoms assessed by UPDRS-III, and 65 Lewy body dementia (LBD) patients with [18F]FDG PET and dopamine radioisotope imaging. Asymmetry indices were calculated for [18F]FDG PET by including the cortex for each hemisphere, for dopamine radioisotope imaging by including the putamen and caudate separately, and for motor symptoms by using the difference between right-left UPDRS-III score. Correlations between these asymmetry indices were explored to test the predictions of the SOC model. To identify cases with a more typical LBD imaging profile, we calculated a Cingulate Island Sign (CIS) index on the [18F]FDG PET image.

RESULTS

We found a significant correlation between cortical interhemispheric [18F]FDG asymmetry and motor-symptom asymmetry in nPD patients (r = 0.62, P = 0.004). In patients with LBD, we found a significant correlation between cortical interhemispheric [18F]FDG asymmetry and dopamine transporter asymmetry in the caudate (r = 0.37, P = 0.0019), but not in the putamen (r = 0.15, P = 0.22). We observed that the correlation in the caudate was stronger in LBD subjects with the highest CIS index, i.e., with more typical LBD imaging profiles.

CONCLUSION

Our study partly supports the SOC model, but further investigations are needed - ideally of de novo, non-demented PD patients.

α-Synuclein: Multiple pathogenic roles in trafficking and proteostasis pathways in Parkinson's disease

Parkinson's disease (PD) is a common age-related neurodegenerative disorder characterized by the loss of dopaminergic neurons in the midbrain. A hallmark of both familial and sporadic PD is the presence of Lewy body inclusions composed mainly of aggregated α-synuclein (α-syn), a presynaptic protein encoded by the SNCA gene. The mechanisms driving the relationship between α-syn accumulation and neurodegeneration are not completely understood, although recent evidence indicates that multiple branches of the proteostasis pathway are simultaneously perturbed when α-syn aberrantly accumulates within neurons. Studies from patient-derived midbrain cultures that develop α-syn pathology through the endogenous expression of PD-causing mutations show that proteostasis disruption occurs at the level of synthesis/folding in the endoplasmic reticulum (ER), downstream ER-Golgi trafficking, and autophagic-lysosomal clearance. Here, we review the fundamentals of protein transport, highlighting the specific steps where α-syn accumulation may intervene and the downstream effects on proteostasis. Current therapeutic efforts are focused on targeting single pathways or proteins, but the multifaceted pathogenic role of α-syn throughout the proteostasis pathway suggests that manipulating several targets simultaneously will provide more effective disease-modifying therapies for PD and other synucleinopathies.

Non-Alzheimer's amnestic mild cognitive impairment with medial temporal hypometabolism

INTRODUCTION

The increasing use of Alzheimer's disease (AD) biomarkers has led to the recognition of a subgroup of non-AD amnestic mild cognitive impairment (aMCI) patients who have medial temporal hypometabolism on fluorodeoxyglucose-positron emission tomography (FDG-PET).

METHODS

In this academic memory-clinic-based consecutive series, 16 non-AD aMCI patients and 28 AD controls matched for sex, age, and baseline Mini-Mental State Examination (MMSE) were followed for a median duration of 4.5 years. Our primary outcome was the MMSE decline rate over the subsequent years. We also determined the final diagnosis over time.

RESULTS

FDG-PET showed more pronounced medial temporal hypometabolism in non-AD cases and more inferior parietal lobule hypometabolism in AD controls. MMSE decline was slower in non-AD (β = -0.51) than in AD (β = -2.00) patients. Five non-AD cases developed frontotemporal dementia years after symptom onset, and one developed dementia with Lewy bodies.

DISCUSSION

Non-AD aMCI patients with medial temporal hypometabolism show slower cognitive decline.

Highlights

Non-AD aMCI with medial temporal hypometabolism shows slower cognitive decline than AD.FDG-PET revealed distinct metabolic patterns between non-AD aMCI and AD patients.Approximately one-third of non-AD aMCI cases developed frontotemporal dementia.Comprehensive diagnostic biomarkers are crucial for non-AD aMCI characterization.

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.

Performance of plasma p-tau217 and NfL in an unselected memory clinic setting

INTRODUCTION

Plasma phosphorylated tau-217 (p-tau217) and neurofilament light (NfL) can differentiate between different dementias in selected cohorts. We aim to test the discrimination potential of these markers in a real-world cohort.

METHODS

We measured p-tau217 (ALZpath) and NfL (Quanterix) in 415 (unselected) consecutive memory clinic patients. Biomarker levels were dichotomized as low/high to create four biomarker profiles based on p-tau217 and NfL levels.

RESULTS

p-Tau217 levels were highest in patients with Alzheimer's disease (AD) dementia, whereas NfL levels were highest in patients with frontotemporal dementia (FTD). Low p-tau217/low NfL was associated mostly with non-neurological diagnoses (79%), and high p-tau217/low NfL indicated AD pathology at any stage (84%). Low p-tau217/high NfL indicated FTD (38%) and high p-tau217/high NfL indicated AD dementia (87%).

DISCUSSION

p-Tau217 can identify AD pathology at any disease stage. NfL can differentiate FTD from other diagnoses (e.g., AD dementia). Plasma p-tau217 and NfL can support clinical decision-making, and we suggest using them as complements to standard clinical assessment.

Highlights

Phosphorylated tau-2017 (p-tau217) can detect Alzheimer's disease (AD) across the clinical continuum.Neurofilament light (NfL) can differentiate frontotemporal dementia (FTD) from other diagnoses (AD dementia, dementia with Lewy bodies [DLB], and Psychiatry).p-Tau217 may detect AD co-pathology in other diseases or dementia types (e.g., DLB).p-Tau217 and NfL show potential for clinical implementation.

Sympathetic 123I-metaiodobenzylguanidine index for Lewy body disease: probability-based diagnosis and identifying patients exempt from late imaging

OBJECTIVE

We aimed to establish a practical diagnostic index for Lewy body diseases (LBD), such as Parkinson's disease and dementia, with Lewy bodies in outpatient settings and criteria for exempting patients from late imaging.

METHODS

We acquired early and late 123I-metaiodobenzylguanidine (MIBG) images from 108 consecutive patients with suspected LBD and standardized heart-to-mediastinum (H/M) ratios for collimator conditions. Exclusions included young-onset Parkinson's disease (age < 50 years) and genetic transthyretin-type amyloidosis. We developed logistic models incorporating H/M ratios with or without age (n = 92). The sympathetic MIBG index for LBD (SMILe index), categorized LBD likelihood from 0 (lowest) to 1 (highest). Diagnostic accuracy was assessed as the area under the receiver operating characteristic (ROC) curve (AUC). The characteristics of the new index were compared with H/M ratios. The need for late imaging was explored using the SMILe index.

RESULTS

Early or late SMILe indexes using a single H/M ratio variable discriminated LBD from non-LBD. The AUC values for early and late SMILe indexes were 0.880 and 0.894 (p < 0.0001 for both), identical to those for early and late H/M ratios. The sensitivity and the specificity of early SMILe indexes with a 0.5 threshold were 76% and 90%, achieving accuracy of accuracy 86%. Similarly, the late SMILe index demonstrated a sensitivity of 76% and specificity of 87%, with an accuracy of 84%. Early SMILe indexes < 0.3 or > 0.7 (representing 84% patients) indicated a diagnosis without a late MIBG study.

CONCLUSION

The 123I-MIBG-derived SMILe indexes provide likelihood of LBD, and those with a 50% threshold demonstrated optimal diagnostic accuracy for LBD. The index values of either < 0.3 or > 0.7 accurately selected patients who do not need late imaging.

Postprandial hypotension is more common than orthostatic hypotension in older adults with dementia with lewy bodies: a cross-sectional study

Cardiovascular autonomic dysfunction is one of the supportive clinical features in dementia with Lewy bodies (DLB). This study aimed to investigate the frequency of postural and postprandial hypotension in people with DLB. The study group comprised 125 patients with DLB (76 females; mean age 78.4 ± 7.1 years) and 122 controls (88 females; mean age 74.4 ± 6.9 years). Postprandial blood pressure changes were assessed by ambulatory 24-hour blood pressure monitorization. Postural blood pressure changes were assessed via the head-up tilt table test. The frequency of postprandial hypotension (PPH) and orthostatic hypotension (OH) was higher in patients with DLB compared to controls (89.4% vs 51.7%; p < 0.001, and 45.5% vs 27.9%; p = 0.004, respectively) whereas the frequency of supine hypertension (SH), and orthostatic hypertension (OHT) was similar. However, SH in non-hypertensive participants was higher in DLB patients than in controls (48.9%, 25.7%; p = 0.035). PPH and OH were independently associated with a diagnosis of DLB (odds ratio [OR]:10.26 confidence interval [CI]%95 3.02-34.82; p < 0.001, and OR:2.22 CI%95 1.2-4.12; p = 0.012, respectively) after adjustment for age, number of medications, use of anti-psychotics drugs, angiotensin receptor blockers, and beta blockers. In conclusion, the study demonstrated that PPH was the most common finding of cardiovascular autonomic dysfunction, followed by OH and SH in older patients with DLB. Given the potential complications of postural blood pressure changes and PPH in such patients, cardiovascular autonomic dysfunction should be evaluated in patients with DLB.

G2019S Mutation of Leucine-Rich Repeat Kinase 2 Is a Cause of Lewy Body Dementia in Patients With North African Ancestors

BACKGROUND

Mutations in the LRRK2 gene are the most common genetic cause of Parkinson disease but are believed to play no significant role in Lewy body disease (LBD).

OBJECTIVES

As the frequency of G2019S LRRK2 mutation is extremely high in North African patients with Parkinson disease, we postulate that the high prevalence of LBD in North Africa might be due to the same mutation because LBD and Parkinson disease share many clinical, pathological, and genetic features.

METHODS

We screened patients with LBD or prodromal LBD for the G2019S mutation of LRRK2.

RESULTS

A total of 162 patients were tested for the mutation, which was present in 5 of the 47 patients with North African ancestors. This is a much higher prevalence (10.6%) than in healthy North African subjects (1.45%) but lower than in North African patients with Parkinson disease (36% to 39%). Carriers tended to develop more often orthostatic hypotension and swallowing problems.

CONCLUSIONS

Where previous studies in European and North American patients found no link between LRRK2 mutations and LBD, we found an LRRK2 mutation associated with Lewy body disease, namely the G2019S mutation that might be restricted to patients with North African ancestors. Our study illustrates the need to introduce ethnic diversity as stratifying factor in the analysis of genetic causes of neurodegenerative disorders. The current development of disease-modifying drugs modulating LRRK2 kinase activity could justify to screen North African patients with LBD for the G2019S LRRK2 mutation.

Analysis of individual alpha frequency in a large cohort from a tertiary memory center

BACKGROUND AND PURPOSE

Precise and timely diagnosis is crucial for the optimal use of emerging disease-modifying treatments for Alzheimer disease (AD). Electroencephalography (EEG), which is noninvasive and cost-effective, can capture neural abnormalities linked to various dementias. This study explores the use of individual alpha frequency (IAF) derived from EEG as a diagnostic and prognostic tool in cognitively impaired patients.

METHODS

This retrospective study included 375 patients from the tertiary Memory Clinic of IRCCS San Raffaele Hospital, Milan, Italy. Participants underwent clinical and neuropsychological assessments, brain imaging, cerebrospinal fluid biomarker analysis, and resting-state EEG. Patients were categorized by amyloid status, the AT(N) classification system, clinical diagnosis, and mild cognitive impairment (MCI) progression to AD dementia. IAF was calculated and compared among study groups. Receiver operating characteristic (ROC) analysis was used to calculate its discriminative performance.

RESULTS

IAF was higher in amyloid-negative subjects and varied significantly across AT(N) groups. ROC analysis confirmed IAF's ability to distinguish A-T-N- from the A+T+N+ and A+T-N+ groups. IAF was lower in AD and Lewy body dementia patients compared to MCI and other dementia types, with moderate discriminatory capability. Among A+ MCI patients, IAF was significantly lower in those who converted to AD within 2 years compared to stable MCI patients and predicted time to conversion (p < 0.001, R = 0.38).

CONCLUSIONS

IAF is a valuable tool for dementia diagnosis and prognosis, correlating with amyloid status and neurodegeneration. It effectively predicts MCI progression to AD, supporting its use in early, targeted interventions in the context of disease-modifying treatments.

Association Between Cancer Screening Patterns and Carer Literacy in Individuals With Cognitive Decline: An Observational Study

OBJECTIVE

The incidence rates of dementia, mild cognitive impairment, and cancer increase with age, posing challenges to affected individuals and their families. However, there are currently no clear cancer screening guidelines for individuals with cognitive impairment. This study analyzed the impact of carer health literacy on screening behaviors in this population.

METHODS

We conducted a postal follow-up survey, associated with the National Center for Geriatrics and Gerontology-Life STORIES of People with Dementia, that targeted primary carers to assess their reports regarding patient attendance at regular cancer screenings recommended by the Japanese Ministry of Health, Labor and Welfare, over the preceding 2 years. Screening rates were compared between the memory clinic cohort and the national average, and the influence of carer health literacy level on screening was analyzed.

RESULTS

Among the 826 total individuals analyzed, the memory clinic cohort exhibited lower breast cancer screening rates, at 11% among female patients aged 65-74 years versus the national average of 32%. Higher health literacy among carers was significantly associated with increased screening. For female patients, carers with high levels of communicative health literacy were more likely to ensure that patients attended screenings for gastric (adjusted odds ratio [AOR], 1.77; 95% confidence interval [CI], 1.03-3.04), colorectal (AOR, 1.70, 95% CI 1.08-2.70), and breast cancers (AOR, 3.08; 95% CI, 1.40-6.76). Among the male patients, high communicative health literacy was associated with increased lung cancer screening attendance (AOR, 1.82; 95% CI, 1.11-2.99).

CONCLUSIONS

Our research highlights a notable gap in cancer screening attendance between individuals with cognitive impairment and the general population, potentially arising from the intricate nature of screening procedures and the extensive burden on carers. More informed decisions and increased screening rates can be achieved through patient-centric communication strategies that accommodate the cognitive abilities of patients, ensuring the comprehensibility and accessibility of health-related information.

Resting-State Functional MRI Approaches to Parkinsonisms and Related Dementia

PURPOSE OF THE REVIEW

In this review, we attempt to summarize the most updated studies that applied resting-state functional magnetic resonance imaging (rs-fMRI) in the field of Parkinsonisms and related dementia.

RECENT FINDINGS

Over the past decades, increasing interest has emerged on investigating the presence and pathophysiology of cognitive symptoms in Parkinsonisms and their possible role as predictive biomarkers of neurodegenerative brain processes. In recent years, evidence has been provided, applying mainly three methodological approaches (i.e. seed-based, network-based and graph-analysis) on rs-fMRI data, with promising results. Neural correlates of cognitive impairment and dementia have been detected in patients with Parkinsonisms along the diseases course. Interestingly, early functional connectivity signatures were proposed to track and predict future progression of neurodegenerative processes. However, longitudinal studies are still sparce and further investigations are needed to overcome this knowledge gap.

The usefulness of combined analysis using CIScore and VSRAD parameters for differentiating between dementia with Lewy body and Alzheimer's disease

PURPOSE

The Cingulate Island score (CIScore) is useful index for differentiating between dementia with Lewy body (DLB) and Alzheimer's disease (AD) using regional cerebral blood flow (rCBF) SPECT. The Z score standing for medial temporal lobe (MTL) atrophy and the ratio of Z score between dorsal brain stem (DBS) to MTL are useful indices for differentiating between DLB and AD using MRI with VSRAD. The current study investigated the diagnostic ability by the combined use of rCBF SPECT and MRI in the differentiation between AD and DLB.

MATERIALS AND METHODS

In cases with 42 AD and 28 DLB undertaken Tc-99m-ECD SPECT and MRI, we analyzed differential diagnostic ability between AD and DLB among following conditions by single or combined settings. Namely, they were (1) the CIScore as a parameter of rCBF SPECT (DLB ≦ 0.25), (2) Z score value of MTL atrophy (DLB ≦ 2.05), (3) the ratio of Z score of DBS to medial temporal gray matter as a parameter of brain atrophy using VSRAD (DLB ≧ 0.38). Also, we analyzed them both including and omitting the elderly (over 75 years old).

RESULTS

The accuracy of differential diagnosis in this condition was 74% for (1), 69% for (2), and 67% for (3). The accuracy by combination condition was 84% for (1) and (2), 81% for (1) and (3), and 67% for (2) and (3), respectively. The combination method by CIScore and the Z score of MTL showed the best accuracy. When we confined condition to ages younger than 75 years, the accuracy improved to 94% in the combination method.

CONCLUSION

The combined use of CIScore and Z score of MTL was suggested to be useful in the differential diagnosis between DLB and AD particularly in younger than 75 years old.

Neuronal alpha-Synuclein Disease integrated staging system performance in PPMI, PASADENA, and SPARK baseline cohorts

The Neuronal alpha-Synuclein Disease (NSD) biological definition and Integrated Staging System (NSD-ISS) provide a research framework to identify individuals with Lewy body pathology and stage them based on underlying biology and increasing degree of functional impairment. Utilizing data from the PPMI, PASADENA, and SPARK studies, we developed and applied biologic and clinical data-informed definitions for the NSD-ISS across the disease continuum. Individuals enrolled as Parkinson's disease, Prodromal, or Healthy Controls were defined and staged based on biological, clinical, and functional anchors at baseline. Across the three studies 1741 participants had SAA data and of these 1030 (59%) were S+ consistent with NSD. Among sporadic PD, 683/736 (93%) were NSD, and the distribution for Stages 2B, 3, and 4 was 25%, 63%, and 9%, respectively. Median (95% CI) time to developing a clinically meaningful outcome was 8.3 (6.2, 10.1), 5.9 (4.1, 6.0), and 2.4 (1.0, 4.0) years for baseline stage 2B, 3, and 4, respectively. We propose pilot biologic and clinical anchors for NSD-ISS. Our results highlight the baseline heterogeneity of individuals currently defined as early PD. Baseline stage predicts time to progression to clinically meaningful milestones. Further research on validation of the anchors in longitudinal cohorts is necessary.

Characteristics associated with progression to probable dementia with Lewy bodies in a cohort with very late-onset psychosis

BACKGROUND

Very late-onset psychosis (VLOP) is associated with higher rates of dementia but the proportion who develop dementia with Lewy bodies (DLB) is unknown. We aimed to identify individuals with VLOP who develop dementia and DLB and characterize the risk factors for progression.

METHODS

Anonymized data were retrieved from electronic records for individuals with VLOP. Patients developing dementia after psychosis were identified, in addition to those with >2 core features of DLB at the time of dementia or DLB identified by a natural language processing application (NLP-DLB). Demographic factors, Health of the National Outcome Scale (HoNOS) and symptoms at index psychosis were explored as predictors of progression to dementia.

RESULTS

In 1425 patients with VLOP over 4.29 years (mean) follow up, 197 (13.8%) received a subsequent diagnosis of dementia. Of these, 24.4% (n = 48) had >2 core features of DLB and 6% (n = 12) had NLP-DLB. In cox proportional hazard models, older age and cognitive impairment at the time of psychosis were associated with increased risk of incident dementia. Visual hallucinations and 2+ core features of DLB at index psychosis were associated with increased risk of dementia with 2+ symptoms of DLB but not all-cause dementia. Two or more core features of DLB at index psychosis were associated with 81% specificity and 67% sensitivity for incident NLP-DLB.

CONCLUSIONS

In patients with VLOP who develop dementia, core features of DLB are common. Visual hallucinations or two core features of DLB in VLOP should prompt clinicians to consider DLB and support further investigation.

The Imbalance of Homocysteine, Vitamin B12 and Folic Acid in Parkinson Plus Syndromes: A Review beyond Parkinson Disease

While there is a link between homocysteine (Hcy), B12 and folic acid and neurodegeneration, especially in disorders like Parkinson's and Alzheimer's diseases, its role in Parkinson plus syndromes (PPS) has only been partially investigated. It appears that elevated Hcy, along with an imbalance of its essential vitamin cofactors, are both implicated in the development and progression of parkinsonian syndromes, which represent different disease pathologies, namely alpha-synucleinopathies and tauopathies. Attributing a potential pathogenetic role in hyperhomocysteinemia would be crucial in terms of improving the diagnostic and prognostic accuracy of these syndromes and also for providing a new target for possible therapeutic intervention. The scope of this review is to focus on vitamin imbalance in PPS, with a special emphasis on the role of Hcy, B12 and folic acid in the neurodegenerative process and their implication in the therapeutic approach of these disorders.

Acute Kidney Injury and Its Association With Dementia and Specific Dementia Types: Findings From a Population-Based Study in Sweden

BACKGROUND AND OBJECTIVES

Preclinical studies suggest that acute kidney injury (AKI) results in biochemical and pathologic changes in the brain. We aimed to explore the association between experiencing AKI and subsequent risks of developing dementia.

METHODS

We conducted a study involving individuals aged 65 years and older in Stockholm from 2006 to 2019, who were free from dementia diagnosis and had data on kidney function. The exposure was an episode of AKI (time varying), ascertained by issued clinical diagnoses and transient creatinine elevations according to Kidney Disease Improving Global Outcomes criteria. The outcome was all-cause dementia and specific types of dementia, ascertained by clinically confirmed cases in the Swedish registry of cognitive/dementia disorders, the presence of 2 issued dementia diagnoses in outpatient care, or initiation of specific antidementia medications. We investigated associations with dementia through Cox proportional hazard regression by AKI, severity levels of AKI, AKI recurrence, and setting (community-acquired or hospital-acquired AKI).

RESULTS

We included 305,122 individuals with a median age of 75 ± 8 years (56.6% women). During a median follow-up of 12.3 (interquartile range 8.7-13.3) years, there were 79,888 individuals (26%) suffering from at least 1 episode of AKI and 47,938 incident cases (16%) of dementia. The rate of dementia cases was 37.0 per 1,000 person-years (95% CI 36.2-37.8) after developing AKI, which was approximately 2 times higher than the rate observed during the periods before AKI (17.3, 95% CI 17.2-17.5). After multivariable adjustment, developing AKI was associated with a 49% higher rate of subsequent dementia (adjusted hazard ratio hazard ratio [HR] 1.49, 95% CI 1.45-1.53). This pattern was consistent across dementia types, with HRs of 1.88 (95% CI 1.53-2.32), 1.47 (1.38-1.56), and 1.31 (1.25-1.38) for dementia with Lewy bodies and Parkinson disease with dementia, vascular dementia, and Alzheimer dementia, respectively. Risk associations were stronger in magnitude across more severe AKIs and in hospital-acquired vs community-acquired AKI.

DISCUSSION

Individuals who experienced an AKI were at increased risk of receiving a diagnosis of dementia.

Brain Evaluation by Dual PET/CT with [18F] FDOPA and [18F] FDG in Differential Diagnosis of Parkinsonian Syndromes

Parkinsonian syndromes are considered clinicopathological conditions that are challenging to diagnose. Molecular imaging with [18F]-FDOPA and [18F]-FDG contributes to a more accurate clinical diagnosis by evaluating presynaptic dopaminergic pathways and glucose metabolism, respectively. The aim of this study was to correlate diagnoses made from dual PET/CT with the initial clinical diagnoses, as well as during follow-ups in patients with Parkinsonian syndromes. A secondary objective was to describe the imaging findings. Methods: A total of 150 patients with a clinical diagnosis of neurodegenerative Parkinsonism were evaluated using dual PET/CT. Clinically, 82% were diagnosed with PD, while the remaining 18% had an atypical Parkinsonism. Results: Using dual PET/CT, the most frequent diagnosis was PD in 67% of the patients, with the rest being diagnosed with an atypical Parkinsonism. In an agreement analysis between the initial clinical diagnosis and the imaging diagnosis by dual PET/CT, a concordance of 94.1% (n = 95) was observed for PD. In the remaining patients, the clinical diagnosis differed from that suggested by dual PET/CT, with atypical Parkinsonian syndromes being diagnosed as DLB in 40% (n = 4), PSP in 46.7% (n = 7), MSA-C in 75% (n = 6), MSA-P in 70% (n = 7), and CBD in 66.7% (n = 4). A total of 38.66% (n = 58) of patients were followed up (median follow-up of 27 months), with a Kappa coefficient of 0.591 (p < 0.001), suggesting substantial agreement. Conclusions: Dual FDOPA-FDG PET/CT demonstrated moderate agreement with the initial clinical diagnosis of Parkinsonism and moderate to substantial agreement during follow-up. This dual technique, therefore, stands out in differentiating between types of Parkinsonisms.

Episodic Coma in Lewy Body Disorders: An Observational Report

Background

and Purpose: Episodes of unresponsiveness are one of several criteria used to diagnose dementia with Lewy bodies and are also seen in people with Parkinson's disease dementia. Patients examined during episodes of coma, whose evaluations found no other explanation than the neurological disorder, have not been described. This paper describes four cases, seen in the past two years. The objective is to bring this uncommon phenomenon to the attention of hospital based neurologists and to demonstrate that this may not be due to autonomic dysfunction.

Methods

These are brief case descriptions by medical personnel observing affected patients supplemented by family reports of similar episodes described on the internet.

Results

Four cases are described, all older men with either dementia with Lewy bodies or Parkinson's disease dementia, who had single, or multiple episodes of otherwise unexplained coma and were examined during a spell. IRB approval waived.

Conclusions

Episodic coma may occur in demented patients with an alpha-synucleinopathy and is the likely explanation when evaluations have found no other cause. This information will reassure the family and patient that this is the likely explanation but that spells may recur.

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.

α-Synuclein Conformations in Plasma Distinguish Parkinson's Disease from Dementia with Lewy Bodies

Aggregation of misfolded α-synuclein (aSyn) within the brain is the pathologic hallmark of Lewy body diseases (LBD), including Parkinson's disease (PD) and dementia with Lewy bodies (DLB). Evidence exists for aSyn "strains" - conformations with distinct biological properties. However, biomarkers for PD vs. DLB, including potential aSyn strain differences, are lacking. Here, we used two monoclonal antibodies selective for different in vitro aSyn species - termed Strain A and B - to evaluate human brain tissue, cerebrospinal fluid (CSF), and plasma. Surprisingly, levels of Strain A and B aSyn species differed in plasma from individuals with PD vs. DLB in two independent cohorts. Lower plasma aSyn Strain A species also predicted subsequent PD cognitive decline. Strain A and Strain B aSyn species were undetectable in CSF, but plasma aSyn species could template aSyn fibrillization, particularly in PD. Our findings suggest that aSyn strains may impact LBD clinical presentation and originate outside the brain.

Neuronal tissue collection from intra-cranial instruments used in deep brain stimulation surgery for Parkinson's disease with implications for study of alpha-synuclein

Alpha-synuclein (αSyn) forms pathologic aggregates in Parkinson's disease (PD) and is implicated in mechanisms underlying neurodegeneration. While pathologic αSyn has been extensively studied, there is currently no method to evaluate αSyn within the brains of living patients. Patients with PD are often treated with deep brain stimulation (DBS) surgery in which surgical instruments are in direct contact with neuronal tissue; herein, we describe a method by which tissue is collected from DBS surgical instruments in PD and essential tremor (ET) patients and demonstrate that αSyn is detected. 24 patients undergoing DBS surgery for PD (17 patients) or ET (7 patients) were enrolled; from patient samples, 81.2 ± 44.8 µg of protein (n = 15), on average, was collected from surgical instruments. Light microscopy revealed axons, capillaries, and blood cells as the primary components of purified tissue (n = 3). ELISA assay further confirmed the presence of neuronal and glial tissue in DBS samples (n = 4). Further analysis was conducted using western blot, demonstrating that multiple αSyn antibodies are reactive in PD (n = 5) and ET (n = 3) samples; truncated αSyn (1-125 αSyn) was significantly increased in PD (n = 5) compared to ET (n = 3), in which αSyn misfolding is not expected (0.64 ± 0.25 vs. 0.25 ± 0.12, P = 0.046), thus showing that multiple forms of αSyn can be detected from living PD patients with this method.

Lewy body pathology exacerbates brain hypometabolism and cognitive decline in Alzheimer's disease

Identifying concomitant Lewy body (LB) pathology through seed amplification assays (SAA) might enhance the diagnostic and prognostic work-up of Alzheimer's disease (AD) in clinical practice and trials. This study examined whether LB pathology exacerbates AD-related disease progression in 795 cognitively impaired individuals (Mild Cognitive Impairment and dementia) from the longitudinal multi-center observational ADNI cohort. Participants were on average 75 years of age (SD = 7.89), 40.8% were female, 184 (23.1%) had no biomarker evidence of AD/LB pathology, 39 (4.9%) had isolated LB pathology (AD-LB+), 395 (49.7%) had only AD pathology (AD+LB-), and 177 (22.3%) had both pathologies (AD+LB+). The AD+LB+ group showed worst baseline performance for most cognitive outcomes and compared to the AD+LB- group faster global cognitive decline and more cortical hypometabolism, particularly in posterior brain regions. Neuropathological examination (n = 61) showed high sensitivity (26/27, 96.3%) and specificity (27/28, 96.4%) of the SAA-test. We showed that co-existing LB-positivity exacerbates cognitive decline and cortical brain hypometabolism in AD. In vivo LB pathology detection could enhance prognostic evaluations in clinical practice and could have implications for clinical AD trial design.

Modeling Lewy body disease with SNCA triplication iPSC-derived cortical organoids and identifying therapeutic drugs

Aggregated α-synuclein (α-SYN) proteins, encoded by the SNCA gene, are hallmarks of Lewy body disease (LBD), affecting multiple brain regions. However, the specific mechanisms underlying α-SYN pathology in cortical neurons, crucial for LBD-associated dementia, remain unclear. Here, we recapitulated α-SYN pathologies in human induced pluripotent stem cells (iPSCs)-derived cortical organoids generated from patients with LBD with SNCA gene triplication. Single-cell RNA sequencing, combined with functional and molecular validation, identified synaptic and mitochondrial dysfunction in excitatory neurons exhibiting high expression of the SNCA gene, aligning with observations in the cortex of autopsy-confirmed LBD human brains. Furthermore, we screened 1280 Food and Drug Administration-approved drugs and identified four candidates (entacapone, tolcapone, phenazopyridine hydrochloride, and zalcitabine) that inhibited α-SYN seeding activity in real-time quaking-induced conversion assays with human brains, reduced α-SYN aggregation, and alleviated mitochondrial dysfunction in SNCA triplication organoids and excitatory neurons. Our findings establish human cortical LBD models and suggest potential therapeutic drugs targeting α-SYN aggregation for LBD.

Neural basis of false recognition in Alzheimer's disease and dementia with lewy bodies

In Alzheimer's disease (AD), reports on the association between false recognition and brain structure have been inconsistent. In dementia with Lewy bodies (DLB), no such association has been reported. This study aimed to identify brain regions associated with false recognition in AD and DLB by analyzing regional gray matter volume (rGMV). We included 184 patients with AD and 60 patients with DLB. The number of false recognitions was assessed using the Alzheimer's Disease Assessment Scale' word recognition task. Brain regions associated with the number of false recognitions were examined by voxel-based morphometry analysis. The number of false recognitions significantly negatively correlated with rGMV in the bilateral hippocampus, left parahippocampal gyrus, bilateral amygdala, and bilateral entorhinal cortex in patients with AD (p < 0.05, family-wise error [FEW] corrected) and in the bilateral hippocampus, left parahippocampal gyrus, right inferior frontal gyrus, right middle frontal gyrus, right basal forebrain, right insula, left medial and lateral orbital gyri, and left fusiform in those with DLB (p < 0.05, FWE corrected). Bilateral hippocampus and left parahippocampal gyrus were associated with false recognition in both diseases. However, we found there were regions where the association between false recognition and rGMV differed from disease to disease.

Real-time fMRI neurofeedback modulates induced hallucinations and underlying brain mechanisms

Hallucinations can occur in the healthy population, are clinically relevant and frequent symptoms in many neuropsychiatric conditions, and have been shown to mark disease progression in patients with neurodegenerative disorders where antipsychotic treatment remains challenging. Here, we combine MR-robotics capable of inducing a clinically-relevant hallucination, with real-time fMRI neurofeedback (fMRI-NF) to train healthy individuals to up-regulate a fronto-parietal brain network associated with the robotically-induced hallucination. Over three days, participants learned to modulate occurrences of and transition probabilities to this network, leading to heightened sensitivity to induced hallucinations after training. Moreover, participants who became sensitive and succeeded in fMRI-NF training, showed sustained and specific neural changes after training, characterized by increased hallucination network occurrences during induction and decreased hallucination network occurrences during a matched control condition. These data demonstrate that fMRI-NF modulates specific hallucination network dynamics and highlights the potential of fMRI-NF as a novel antipsychotic treatment in neurodegenerative disorders and schizophrenia.

Clinical, neuropathological, and molecular characteristics of rapidly progressive dementia with Lewy bodies: a distinct clinicopathological entity?

BACKGROUND

The term rapidly progressive dementia (RPD) with Lewy bodies (rpDLB) is used for DLB patients who develop a rapidly progressive neurological syndrome and have reduced survival. Here, we characterise the clinical, neuropathological, and molecular characteristics of a large rpDLB neuropathological series.

METHODS

We included all RPD patients with a disease duration < 4 years submitted to our prion disease referral centre between 2003 and 2022 who showed Lewy body pathology (LBP) in limbic or neocortical stages as primary neuropathological diagnosis, had no systemic condition justifying the rapid deterioration and were previously neurologically unimpaired. Clinical features were retrieved and compared with Creutzfeldt-Jakob disease (CJD) and rapidly progressive Alzheimer's disease (rpAD) cohorts. Neuropathological and genetic (whole exome sequencing, APOE genotyping, and C9orf72 repeat expansion analysis) characteristics of rpDLB patients were systematically investigated. We scored semi-quantitatively the LBP load and performed a α-synuclein (αSyn) RT-QuIC seeding amplification assay (SAA) on cerebrospinal fluid (CSF) and tenfold serially diluted brain homogenates from different brain areas in rpDLB patients and typical long-lasting Lewy body disease (LBD) with dementia patients as control group.

RESULTS

RpDLB patients were older (p = 0.047) and presented more cognitive fluctuations (p = 0.005), visual hallucinations (p = 0.020), neuropsychiatric symptoms (p = 0.006) and seizures (p = 0.032), and fewer cerebellar (p < 0.001) and visual (p = 0.004) signs than CJD ones. Delirium onset was more common than in both CJD (p < 0.001) and rpAD (p = 0.008). Atypical LBD signs (pyramidal, myoclonus, akinetic mutism) were common. All tested patients were positive by CSF αSyn SAA. Concomitant pathologies were common, with only four cases showing relatively "pure" LBP. LBP load and αSyn seeding activity measured through αSyn RT-QuIC SAA were not significantly different between rpDLB patients and typical LBD. We found a likely pathogenic variant in GBA in one patient.

CONCLUSIONS

Our results indicate that: 1) rpDLB exhibits a distinct clinical signature (2) CSF αSyn SAA is a reliable diagnostic test; 3) rpDLB is a heterogeneous neuropathological entity that can be underlain by both widespread pure LBP, or multiple copathologies 4) rpDLB is likely not sustained by distinct αSyn conformational strains; 5) genetic defects may, at least occasionally, contribute to the poor prognosis in these patients.

Neuronal alpha-Synuclein Disease Integrated Staging System performance in PPMI, PASADENA, and SPARK baseline cohorts

The Neuronal alpha-Synuclein Disease (NSD) biological definition and Integrated Staging System (NSD-ISS) provide a research framework to identify individuals with Lewy body pathology and stage them based on underlying biology and increasing degree of functional impairment. Utilizing data from the PPMI, PASADENA and SPARK studies, we developed and applied biologic and clinical data-informed definitions for the NSD-ISS across the disease continuum. Individuals enrolled as Parkinson's disease, Prodromal, or Healthy Controls were defined and staged based on biological, clinical, and functional anchors at baseline. Across the three studies 1,741 participants had SAA data and of these 1,030 (59%) were S+ consistent with NSD. Among sporadic PD, 683/736 (93%) were NSD, and the distribution for Stages 2B, 3, and 4 was 25%, 63%, and 9%, respectively. Median (95% CI) time to developing a clinically meaningful outcome was 8.3 (6.2, 10.1), 5.9 (4.1, 6.0), and 2.4 (1.0, 4.0) years for baseline stage 2B, 3, and 4, respectively. We propose pilot biologic and clinical anchors for NSD-ISS. Our results highlight the baseline heterogeneity of individuals currently defined as early PD. Baseline stage predicts time to progression to clinically meaningful milestones. Further research on validation of the anchors in longitudinal cohorts is necessary.

Influence of Different Diagnostic Criteria on Alzheimer Disease Clinical Research

BACKGROUND AND OBJECTIVES

Updates in Alzheimer disease (AD) diagnostic guidelines by the National Institute on Aging-Alzheimer's Association (NIA-AA) and the International Working Group (IWG) over the past 11 years may affect clinical diagnoses. We assessed how these guidelines affect clinical AD diagnosis in a cohort of cognitively unimpaired (CU) and cognitively impaired (CI) individuals.

METHODS

We applied clinical and biomarker data in algorithms to classify individuals from the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort according to the following diagnostic guidelines for AD: 2011 NIA-AA, 2016 IWG-2, 2018 NIA-AA, and 2021 IWG-3, assigning the following generic diagnostic labels: (1) not AD (nAD), (2) increased risk of developing AD (irAD), and (3) AD. Diagnostic labels were compared according to their frequency, convergence across guidelines, biomarker profiles, and prognostic value. We also evaluated the diagnostic discordance among the criteria.

RESULTS

A total of 1,195 individuals (mean age 73.2 ± 7.2 years, mean education 16.1 ± 2.7, 44.0% female) presented different repartitions of diagnostic labels according to the 2011 NIA-AA (nAD = 37.8%, irAD = 23.0%, AD = 39.2%), 2016 IWG-2 (nAD = 37.7%, irAD = 28.7%, AD = 33.6%), 2018 NIA-AA (nAD = 40.7%, irAD = 9.3%, AD = 50.0%), and 2021 IWG-3 (nAD = 51.2%, irAD = 8.4%, AD = 48.3%) frameworks. Discordant diagnoses across all guidelines were found in 512 participants (42.8%) (138 [91.4%] occurring in only β-amyloid [CU 65.4%, CI 34.6%] and 191 [78.6%] in only tau-positive [CU 71.7%, CI 28.3%] individuals). Differences in predicting cognitive impairment between nAD and irAD groups were observed with the 2011 NIA-AA (hazard ratio [HR] 2.21, 95% CI 1.34-3.65, p = 0.002), 2016 IWG-2 (HR 2.81, 95% CI 1.59-4.96, p < 0.000), and 2021 IWG-3 (HR 3.61, 95% CI 2.09-6.23, p < 0.000), but not with 2018 NIA-AA (HR 1.69, 95% CI 0.87-3.28, p = 0.115).

DISCUSSION

Over 42% of the studied population presented discordant diagnoses when using the different examined AD criteria, mostly in individuals with a single positive biomarker. Except for 2018 NIA-AA, all guidelines identified asymptomatic individuals at risk of cognitive impairment. Our findings highlight important differences between the guidelines, emphasizing the necessity for updated criteria with enhanced staging metrics, considering clinical, research, therapeutic, and trial design aspects.

Base rates of healthy community-dwelling adults meeting criteria for traumatic encephalopathy syndrome and levels of chronic traumatic encephalopathy certainty

Objective: The National Institute of Neurological Disorders and Stroke (NINDS) recently revised criteria for Traumatic Encephalopathy Syndrome (TES) (Katz et al.), aiming to improve the specificity of former TES criteria (Montenigro et al.) and adding methods to gauge certainty of underlying Chronic Traumatic Encephalopathy (CTE). This study examined base rates of Montenigro et al. and Katz et al. TES criteria in healthy community-dwelling adults. Method: Participants consisted of healthy adults (n = 835; M = 48.1 ± 18.2 years-old, range = 18-85; 37.1% male; 64.1% White) without known history of neurotrauma or psychiatric or neurological conditions. The former and current TES criteria were operationalized using the NIH Toolbox Cognition, Motor, and Emotion batteries and PROMIS-29. Results: Per Katz et al. criteria, 36.9% had symptoms Suggestive of CTE (i.e. either cognitive impairment or neurobehavioral dysregulation), 4.1% had Possible CTE (i.e. requiring cognitive impairment and two additional criteria), and 0.8% had Probable CTE (i.e. requiring cognitive impairment and three additional criteria). The requirement of cognitive impairment for Possible CTE certainty decreased the base rate of Possible CTE tenfold from Montenigro et al. criteria (40.1%). Conclusion: The Katz et al. criteria were met less frequently by healthy adults than the Montenigro et al. criteria. Requiring cognitive impairment and more supportive TES features when gauging CTE certainty may reduce false-positive diagnoses. This finding supports the role of neuropsychologists in the diagnosis and monitoring of patients in TES research studies. To assess specificity, future research should examine base rates of Katz et al. criteria in other psychiatric and neurological conditions.

Utility of neuromelanin-sensitive MRI in the diagnosis of dementia with Lewy bodies

OBJECTIVE

Dementia with Lewy bodies (DLB) is recognized as the second most common cause of degenerative dementia in older people with Alzheimer's disease (AD), and distinguishing between these 2 diseases may be challenging in clinical practice. However, accurate differentiation is important because these 2 diseases have different prognoses and require different care. Recently, several studies have reported that neuromelanin-sensitive MRI can detect neurodegeneration in the substantia nigra pars compacta (SNc). DLB patients are considered to demonstrate degeneration and a reduction of dopaminergic neurons in the SNc. Therefore, neuromelanin-sensitive MRI may be useful for the diagnosis of DLB. Therefore, in this study, we aimed to investigate the usefulness of neuromelanin-sensitive MRI in the distinguishing DLB from AD.

METHODS

A total of 21 probable DLB and 22 probable AD patients were enrolled. All participants underwent both DaT-SPECT and neuromelanin-sensitive MRI. A combined model of neuromelanin-sensitive MRI and Dopamine transporter single-photon emission computed tomography (DaT-SPECT) was created using logistic regression analysis (forced entry method).

RESULTS

There was no difference in the diagnostic utility of neuromelanin-sensitive MRI and DaT-SPECT in distinguishing DLB from AD. There was no significant correlation between the results of neuromelanin-sensitive MRI and DaT-SPECT in DLB patients. The combination of neuromelanin-sensitive MRI and DaT-SPECT demonstrated higher diagnostic performance in distinguishing between DLB and AD compared with neuromelanin-sensitive MRI alone. Additionally, although the combination of both modalities showed a larger AUC compared with DaT-SPECT alone, the difference was not statistically significant.

CONCLUSIONS

Neuromelanin-sensitive MRI may be equally or even more useful than DaT-SPECT in the clinical differentiation of DLB from AD. Furthermore, the combination of neuromelanin-sensitive MRI and DaT-SPECT may be a highly sensitive imaging marker for distinguishing DLB from AD.

Factors Associated with Increased Burden of Caregivers of People with Dementia with Lewy Bodies

The burden of caregivers of people with dementia with Lewy bodies (DLB) is high; however, factors related to their caregiving burden are not fully clarified. We herein investigated factors associated with increasing caregiver burden for caregivers of people with DLB. To explore factors associated with caregiver burden, a linear regression analysis was conducted using the J-ZBI_8 total score as the dependent variable and a total of 36 factors as independent variables. This analysis included 252 pairs of people with DLB and their caregivers. Caregivers' mean J-ZBI_8 was 8.4, indicating that caregiver burden was generally high. First, we identified 20 factors associated with caregiver burden in univariable analysis. Finally, multivariable analysis found three significant factors: irritability (β = 0.208, p < 0.001), use of "short stay" or "small-scale, multifunctional home care" (β = 0.208, p < 0.001), and nighttime behavior (β = 0.138, p = 0.020) were significantly associated with J-ZBI_8 total scores. Irritability and nighttime behavior were found to be contributing factors to caregiver burden. High caregiver burden among caregivers of people with DLB may result in the use of social services providing overnight stays, but to what extent such services reduce caregiver burden is unknown.