Features Of Dementia With Lewy Bodies Research Articles

Dementia with Lewy bodies – a case report, diagnosis and management

Dementia is one of the major health issues around the globe which can severely affect the daily functioning of patients and their caregivers. There is no pharmacological method that entirely cures dementia, however, early detection, precognitive medication and treatment of concomitant illnesses and behavioural symptoms can significantly moderate cognitive decline as well as improve the quality of life patients with dementia. Here we present a case of Dementia with Lewy Bodies (DLB), which is the second most common form of neurodegenerative dementia in population above 65 years old. Despite its common occurrence, this disease is rarely detected, due to misleading symptoms, in its early stage. DLB often starts with depressive or psychotic symptoms, whilst cognitive decline is not apparent yet. Clinical features of DLB, as well as challenges of diagnosis and management are presented accordingly.

Sex differences for phenotype in pathologically defined dementia with Lewy bodies

IntroductionSex differences in dementia with Lewy bodies (DLB) have been reported in clinically defined cohorts; however, clinical diagnostic accuracy in DLB is suboptimal and phenotypic differences have not been assessed...

Prevalence and Associated Factors of Visual Hallucinations in Patients with Vascular Cognitive Impairment.

Visual hallucinations (VHs) are striking features for dementia, especially dementia with Lewy bodies (DLB). We aimed to study the frequency and associated factors of VH in vascular cognitive impairment (VCI) and investigate the feasibility of clinically diagnosing the mixed pathology of VCI with DLB. This is a multicentre registration study. A consecutive series of VCI patients with and without dementia were enrolled. Frequency of VH and associated factors, including age, gender, education, disease severity, DLB clinical features, vascular risk factors, cognitive function, and neuropsychiatric symptoms, were compared between VCI with VH (VH+) and without VH (VH−). Among the 1281 patients analysed, 155 (12.1%) had VH. The VH+ group was older (t = 5.07; p < 0.001), was more likely to be female (χ2 = 13.46; p < 0.001), and has a higher clinical dementia rating (χ2 = 70.51; p < 0.001). After adjusting for age, gender, and disease severity, the VH+ group had poorer cognition and more severe neuropsychiatric symptoms. The VH+ group was more associated with DLB features in fluctuating cognition (OR = 2.48; p < 0.001), parkinsonism (OR = 1.85; p = 0.001), rapid eye movement (REM) behavioral disorder (OR = 4.56; p < 0.001), and ≧2 DLB core features (OR = 26.01; p < 0.001). VCI patients with VH tend to have more severe dementia, neuropsychiatric symptoms, and poorer cognitive function. Additionally, highly associated with clinical DLB features in VCI with VH raised the possibility of mixed pathology with DLB in this group. More than two core features in VCI might help in diagnosing a mixed pathology with DLB.

Prevalence and severity of neuropsychiatric symptoms in the prodromal stages of dementia with Lewy bodies and Alzheimer’s disease

AbstractBackgroundThere has been minimal investigation into the prodromal features dementia with Lewy bodies (DLB) and how they may differ from prodromal features of Alzheimer’s disease (AD).MethodThe data analyzed for this investigation were collected as part of a large, prospective longitudinal study conducted by the National Alzheimer’s Coordinating Center (NACC database is funded by NIA/NIH Grant U01 AG016976). We identified 110 non‐demented participants who converted to DLB at a subsequent visit. Participants were age and sex matched to 220 non‐demented participants who later converted to AD. We examined between group differences in the prevalence of symptoms on the Neuropsychiatric Inventory Questionnaire (NPI‐Q) at time of dementia diagnosis and in the 1‐3 years preceding conversion to dementia using Chi‐Square or Fisher Exact Test analyses.ResultsFor the DLB and AD groups, 82% were male and the average age at the time of dementia diagnosis was 75.4 years (SD=7.9). There was no significant difference in education between the two groups. The DLB group was significantly less culturally diverse than the AD group (See Table 1). Nighttime behaviors and hallucinations were significantly more common in the DLB group compared to the AD group at all time points during the prodromal phase and at the time of dementia diagnosis. There was no significant difference in the informant’s report of motor symptoms in the prodromal phases between the two groups (See Table 2).ConclusionThe DLB group demonstrated a significantly higher prevalence of nighttime behaviors and hallucinations than the AD group in both the prodromal phase and at the time of dementia diagnosis. These findings support the occurrence of core clinical features of DLB during the prodromal phase of the disease [1]; however, there was no significant difference in the informant’s report of motor symptoms within the prodromal phases, which warrants a comparison utilizing more objective motor data. Reference: 1. McKeith IG, Boeve BF, Dickson DW, et al.; Dementia with Lewy Bodies Consortium. Diagnosis and management of Dementia with Lewy Bodies: Fourth consensus report of the DLB Consortium. Neurol. 2017;89:1‐13.

Intrinsic Alertness Is Impaired in Patients with Nigrostriatal Degeneration: A Prospective Study with Reference to [123I]FP-CIT SPECT and [18F]FDG PET.

Variations in alertness and attention are common in Lewy body diseases (LBD) and among the core features of dementia with Lewy bodies (DLB). Dopamine transporter SPECT is an accurate biomarker of nigrostriatal degeneration (NSD) in LBD. The present study investigated performance on a computerized alertness test as a potential measure of attention in patients with NSD compared to patients without NSD. Thirty-six patients with cognitive impairment plus at least one core feature of DLB referred for [123I]FP-CIT SPECT imaging were prospectively recruited. Performance in a computerized test of intrinsic alertness was compared between patients with and those without NSD as assessed by [123I]FP-CIT SPECT. Reaction times to auditory stimuli (adjusted for age, sex, and education) were significantly longer in patients with NSD compared to those with a normal [123I]FP-CIT SPECT scan (p < 0.05). Statistical analyses revealed no significant differences comparing reaction times to visual stimuli or dispersion of reaction times between groups. Exploratory analysis in a subgroup of patients with available [18F]FDG PET revealed that longer reaction times were associated with decreased glucose metabolism in the prefrontal cortex (statistical parametric mapping, adjusted for age and sex; p < 0.005, cluster extent > 50 voxels). Computerized assessment of auditory reaction times is able to detect alertness deficits in patients with NSD and might help to measure alertness deficits in patients with LBD and NSD. Future studies in larger samples are needed to evaluate the diagnostic utility of computerized alertness assessment for the differential diagnosis of LBD.

β-Amyloid and tau biomarkers and clinical phenotype in dementia with Lewy bodies

In a multicenter cohort of probable dementia with Lewy bodies (DLB), we tested the hypothesis that β-amyloid and tau biomarker positivity increases with age, which is modified by APOE genotype and sex, and that there are isolated and synergistic associations with the clinical phenotype. We included 417 patients with DLB (age 45-93 years, 31% women). Positivity on β-amyloid (A+) and tau (T+) biomarkers was determined by CSF β-amyloid1-42 and phosphorylated tau in the European cohort and by Pittsburgh compound B and AV-1451 PET in the Mayo Clinic cohort. Patients were stratified into 4 groups: A-T-, A+T-, A-T+, and A+T+. A-T- was the largest group (39%), followed by A+T- (32%), A+T+ (15%), and A-T+ (13%). The percentage of A-T- decreased with age, and A+ and T+ increased with age in both women and men. A+ increased more in APOE ε4 carriers with age than in noncarriers. A+ was the main predictor of lower cognitive performance when considered together with T+. T+ was associated with a lower frequency of parkinsonism and probable REM sleep behavior disorder. There were no significant interactions between A+ and T+ in relation to the clinical phenotype. Alzheimer disease pathologic changes are common in DLB and are associated with the clinical phenotype. β-Amyloid is associated with cognitive impairment, and tau pathology is associated with lower frequency of clinical features of DLB. These findings have important implications for diagnosis, prognosis, and disease monitoring, as well as for clinical trials targeting disease-specific proteins in DLB. This study provides Class II evidence that in patients with probable DLB, β-amyloid is associated with lower cognitive performance and tau pathology is associated with lower frequency of clinical features of DLB.

Neuropsychiatric profiles in mild cognitive impairment with Lewy bodies

Objectives To compare the neuropsychiatric symptoms (NPS) of patients with mild cognitive impairment with Lewy bodies (MCI-LB) with those with mild cognitive impairment due to Alzheimer’s disease (MCI-AD). Method Subjects with probable MCI-LB (n = 53), MCI-AD (n = 60), dementia with Lewy bodies (DLB) (n = 97) and AD (n = 202) were recruited. All were older than 60 years. Neuropsychiatric profiles were evaluated by the Neuropsychiatric Inventory (NPI). The Lewy Body Neuropsychiatric Supportive Symptom Count (LBNSSC) was used to assess give supportive clinical features of DLB (systematized delusions, hallucinations in non-visual modalities, apathy, anxiety, and depression). Results Compared with MCI-AD, those with MCI-LB had higher total NPI scores on prevalence and severity, as were prevalence and severity in visual hallucinations and rapid eye movement sleep behavior disorder (RBD). The MCI-LB group had a higher LBNSSC than did the MCI-AD group. Compared with 20% of those with MCI-AD, 41.5% of those with MCI-LB had two or more supportive NPS, (likelihood ratio = 2.08, p = 0.013). MCI-LB subjects showed a high prevalence in apathy, depression, and appetite/eating disorders items. Conclusion The NPI is a useful tool to detect NPS in those with MCI-LB. The MCI-LB group had a higher prevalence of core features (visual hallucinations and RBD) and a higher LBNSSC than the MCI-AD group. These features could help to differentiate MCI-LB and MCI-AD.

Dementia with Lewy bodies and Parkinson’s disease dementia-two independent disorders or one clinical entity within a clinical spectrum of synucleinopathies?

Abstract Introduction: Introduction: Both dementia with Lewy bodies (DLB) and Parkinson’s disease dementia (PDD) are important dementia syndromes that overlap in their clinical features and clinical course, neuropathological abnormalities, and also therapeutic approach. Nevertheless it is still unclear whether DLB and PDD are two different disorders that require differentiation or are one clinical entity within a spectrum of Lewy body disease. Currently these disorders are mainly distinguished on the basis of the relative timing of the onset of symptoms of dementia and parkinsonism. The present paper presents current concepts on the pathogenesis of both disorders and their possible overlap. Material and methods: Online databases in the field of DLB and PDD were searched for to find potentially eligible articles. Only most recent articles published after the year 2000 were chosen. Results: The clinical features of DLB and PDD are similar and include dementia with hallucinations and cognitive fluctuations, as well as parkinsonian signs. Also cognitive deficits are similar in PDD and in DLB, with predominance of executive dysfunction, visual-spatial deficits and memory impairment. Neuropathological changes in both disorders involve the presence of Lewy bodies and Lewy neurites within brainstem, limbic and neocortex, as well as loss of midbrain dopamine cells, and loss of cholinergic neurons in the nuclei of ventral forebrain. Conclusions: Similarities in clinical manifestation, neuropsychological deficits and neuropathological abnormalities may suggest that both DLB and PDD are two different phenotypes of the same disorder. This review article presents current knowledge on similarities and differences between these two clinical entities and raises the question whether they require differentiation or not.

The challenges of COVID-19 for people with dementia with Lewy bodies and family caregivers.

The challenges of COVID-19 for people with dementia with Lewy bodies and family caregivers.

Cardiac and Blood Pressure Safety of Transdermal Rivastigmine in Elderly Patients With Dementia With Lewy Bodies.

Dementia with Lewy bodies (DLB) is the second most common dementia. Features of DLB include postganglionic cardiac sympathetic denervation and autonomic instability. Rivastigmine therapy, an acetylcholinesterase inhibitor, is widely used in the primary treatment of DLB; however, the cardiovascular safety and tolerability of transdermal rivastigmine needs to be reviewed. To evaluate whether transdermal rivastigmine has an effect on blood pressure, heart rate, and electrocardiography measurements. A total of 722 patients diagnosed with dementia were retrospectively screened. Fifty-seven of 98 DLB patients who received transdermal rivastigmine treatment with available serial electrocardiography and blood pressure measurements were included in the study. Baseline and follow-up measurements were compared for patients on the 9.5 to 13.3 mg/d rivastigmine dose for at least 4 weeks. The mean age of the patients was 80.77±6.04, and the majority were women (63%). A total of 8 cases with bradycardia and 5 with orthostatic hypotension were detected during follow-up, and rivastigmine patch was stopped in one of those 8 patients due to symptomatic bradycardia. Nonetheless, there was no difference between baseline and follow-up measurements of the patients, including heart rate, cardiac rhythm, electrocardiographic intervals, blood pressure, pulse pressure, and postural blood pressure changes. Transdermal rivastigmine therapy is not associated with arrhythmogenic or hypotensive effects in the elderly patients with DLB. However, when prescribing transdermal rivastigmine, physicians should pay attention to newly emerging orthostatic hypotension during the follow-up in these patients.

Cognitive Decline in Mild Cognitive Impairment With Lewy Bodies or Alzheimer Disease: A Prospective Cohort Study

ObjectiveWe explored whether the mild cognitive impairment (MCI) stages of dementia with Lewy bodies (DLB) and Alzheimer disease (AD) differ in their cognitive profiles, and longitudinal progression. DesignA prospective, longitudinal design was utilized with annual follow-up (Max 5 years, Mean 1.9, standard deviation 1.1) after diagnosis. Participants underwent repeated cognitive testing, and review of their clinical diagnosis and symptoms, including evaluation of core features of DLB. SettingThis was an observational study of independently living individuals, recruited from local healthcare trusts in North East England, UK. ParticipantsAn MCI cohort (n = 76) aged ≥60 years was utilized, differentially diagnosed with MCI due to AD (MCI-AD), or possible/probable MCI with Lewy bodies (MCI-LB). MeasurementsA comprehensive clinical and neuropsychological testing battery was administered, including ACE-R, trailmaking tests, FAS verbal fluency, and computerized battery of attention and perception tasks. ResultsProbable MCI-LB presented with less impaired recognition memory than MCI-AD, greater initial impairments in verbal fluency and perception of line orientation, and thereafter demonstrated an expedited decline in visuo-constructional functions in the ACE-R compared to MCI-AD. No clear diagnostic group differences were found in deterioration speeds for global cognition, language, overall memory, attention or other executive functions. ConclusionThese findings provide further evidence for differences in severity and decline of visuospatial dysfunctions in DLB compared with AD; further exploration is required to clarify when and how differences in attention, executive, and memory functions emerge, as well as speed of decline to dementia.

Neuroinflammation in dementia with Lewy bodies: a human post-mortem study

Dementia with Lewy bodies (DLB) is the second most common neurodegenerative cause of dementia, behind Alzheimer’s disease (AD). It is now established that cerebral inflammation has a key role in the aetiology and progression of AD, but this has yet to be confirmed in DLB. We aimed to determine the neuroinflammatory profile in the cerebral cortex of a large cohort of DLB cases. Thirty post-mortem confirmed DLB cases and twenty-nine matched controls were immunolabelled (Brodmann area 21) and quantified for: neuropathology—αSYN, Aβ, P-tau; microglial phenotype—Iba1, HLA-DR, CD68, FcƴR (CD64, CD32a, CD32b, CD16); presence of T lymphocytes—CD3; and anti-inflammatory markers—IL4R, CHI3L1. Status spongiosis, as a marker of neuropil degeneration, was quantified using Haematoxylin and Eosin staining. We found no significant difference between groups in protein load for Iba1, HLA-DR, CD68, CD64, CD32b, IL4R, or CHI3L1, despite increased neuropathology in DLB. CD32a load was significantly lower, and CD16 load higher, in DLB compared with controls. There was no difference in status spongiosis between groups. Significantly more DLB cases than controls showed T-lymphocyte recruitment. Overall, we conclude that microglial activation is not a prominent feature of DLB, and that this may be associated with the relatively modest neuropil degeneration observed in DLB. Our findings, based on the largest post-mortem cohort to date exploring neuroinflammation in DLB, demonstrate a dissociation between protein deposition, neurodegeneration and microglial activation. The relative preservation of cortical structures in DLB suggests the dementia could be more amenable to potential therapies.

Pathological and clinical comparison of Parkinson’s disease dementia and dementia with Lewy bodies.

Dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD) are two major neurodegenerative diseases sharing common clinical, pathophysiological and morphologic features. The pathological hallmark of both diseases is the presence of Lewy-bodies (LB). The main constituent of these inclusions is the pathologically aggregated α-synuclein protein. In DLB, LBs are predominantly located in the cortex, whereas in PDD, the subcortical regions are predominantly affected. Furthermore, in DLB, coexisting Alzheimer's disease (AD), pathology with β-amyloid plaques and neurofibrillary tangles are more common. It is still debated whether DLB and PDD are two distinct entities or different phenotypes of the same disease. Clinical diagnosis is based on the temporal sequence of motor and cognitive symptoms. Dementia often precedes parkinsonism in DLB, while in PDD, cognitive decline generally appears after the onset of motor symptoms. Also, fluctuation of cognitive functions and neuroleptic sensitivity is more severe in DLB than PDD. The recent advancements of imaging techniques revealed that cortical damage, cholinergic deficit and concomitant AD pathology are more severe in DLB compared to PDD. The analysis of cerebrospinal fluid biomarkers shows higher oligomeric α-synuclein burden in PDD. Levodopa is less effective in DLB than in PDD and may increase the risk of psychosis. In this review, we comprehensively analyse the pathological, radiological and clinical features of DLB and PDD, highlighting the overlaps and differences. Orv Hetil. 2020; 161(18): 727-737.

Anxiety symptoms are quantitatively and qualitatively different in dementia with Lewy bodies than in Alzheimer's disease in the years preceding clinical diagnosis.

Dementia with Lewy bodies (DLB) is a common but underdiagnosed type of cognitive impairment and dementia. The current diagnostic criteria for research purposes have a high specificity but lack sensitivity. Moreover, patients who live alone are not always aware that they have core clinical features such as cognitive fluctuations, visual hallucinations, and parasomnia. Anxiety is a common and early manifestation in DLB. We matched 41 DLB patients with 41 patients with Alzheimer's disease (AD) according to gender, age, and cognitive status and retrospectively analyzed their files for the presence of anxiety, depression, constipation, and the core clinical features of DLB in the documented period before diagnosis. Anxiety, but not depression, occurred significantly more frequently in DLB than in AD (63.4% vs 26.8%). It appears up to 4-5 years before the diagnosis of DLB and is associated with depression and living at home. Anxiety in DLB was often described as intermittent panic attacks without reason or during states of delirium; it was also severe enough to require medical treatment and inpatient or outpatient psychiatric care. It was often mistaken for a psychiatric illness or a manifestation of other common forms of dementia. Anxiety in AD seemed much milder, was often related to the patient's coping with cognitive dysfunction, and was never cited as a specific reason for medical help. The concomitant presence of anxiety with at least one core clinical criterion of DLB enabled us to differentiate it from AD in our study, with a sensitivity of 63.4% but a specificity of 100%. In all patients over 50 who present with cognitive problems and anxiety, DLB should be considered. Patients and informants should be carefully questioned regarding the presence of other typical signs and symptoms of DLB.

Clinical features of Lewy body dementia: insights into diagnosis and pathophysiology.

The recent revision of the consensus diagnostic criteria for dementia with Lewy bodies (DLB) incorporates an expansive set of core and supportive clinical features. However, the relationship between all features and optimal methods for their assessment has yet to be assessed within a single cohort. This has the potential to yield novel pathological insights and streamline diagnostic algorithms. Twenty-seven prospectively recruited probable DLB patients and 25 age-matched controls were assessed and core and supportive features scored using a unique combination of established clinical and research instruments. Prevalence of all features was reported and diagnostic methods were evaluated. An exploratory factor analysis was performed to uncover latent associations. Six independent factors were identified accounting for 81% of the diagnostic variance across all core and supportive clinical features. Within these factors, pathologically plausible relationships were highlighted between hallucinations, cognitive fluctuations, and excessive daytime somnolence; between REM sleep behaviour disorder (RBD) and postural hypotension as well as between Parkinsonism and urinary disturbance. 'Prodromal' DLB symptoms were represented in the remaining three factors. The UPDRS and RBD screening questionnaire were evaluated for their suitability for detecting DLB core features and a novel DLB-Parkinsonism scale is proposed to help standardize diagnosis (AUC = 0.94; 95% CI 0.81-1.00). Clusters of specific core and supportive DLB features are identified, which together with the evaluated screening instruments evaluated, may inform improved strategies to diagnose DLB in clinical and research settings.

Vulnerability of multiple large-scale brain networks in dementia with Lewy bodies.

Aberrations of large-scale brain networks are found in the majority of neurodegenerative disorders. The brain connectivity alterations underlying dementia with Lewy bodies (DLB) remain, however, still elusive, with contrasting results possibly due to the pathological and clinical heterogeneity characterizing this disorder. Here, we provide a molecular assessment of brain network alterations, based on cerebral metabolic measurements as proxies of synaptic activity and density, in a large cohort of DLB patients (N = 72). We applied a seed-based interregional correlation analysis approach (p < .01, false discovery rate corrected) to evaluate large-scale resting-state networks' integrity and their interactions. We found both local and long-distance metabolic connectivity alterations, affecting the posterior cortical networks, that is, primary visual and the posterior default mode network, as well as the limbic and attention networks, suggesting a widespread derangement of the brain connectome. Notably, patients with the lowest visual and attention cognitive scores showed the most severe connectivity derangement in regions of the primary visual network. In addition, network-level alterations were differentially associated with the core clinical manifestations, namely, hallucinations with more severe metabolic dysfunction of the attention and visual networks, and rapid eye movement sleep behavior disorder with alterations of connectivity of attention and subcortical networks. These multiple network-level vulnerabilities may modulate the core clinical and cognitive features of DLB and suggest that DLB should be considered as a complex multinetwork disorder.

ALTERED SLEEP-WAKE MECHANISMS IN NEURODEGENERATIVE DISEASE: SIMILARITIES AND DIFFERENCES BETWEEN LEWY BODY DISEASE AND NARCOLEPSY

Lewy body disease (LBD) is a synucleinopathy which affects central and peripheral (particularly autonomic) nervous system networks, with the clinical features in affected individuals often spanning several domains when fully manifested. Dementia with Lewy bodies (DLB) represents that dementia-predominant phenotype associated with LBD pathology, whereas Parkinson's disease is the motor-predominant phenotype. REM sleep behavior disorder (RBD) is strongly associated with LBD pathology, and is one of the most common early clinical manifestations of an evolving synucleinopathy. Many of the core clinical manifestations of narcolepsy – excessive daytime sleepiness, visual hallucinations and RBD – overlap with DLB. Literature review and presentation of new data. This presentation will involve discussion of three major topics: 1) the presumed pathophysiology and associated clinical and biomarker findings of RBD, 2) the clinical phenomenology and presumed pathophysiologic mechanisms underlying excessive daytime sleepiness, visual hallucinations during wakefulness, and RBD in the setting of DLB, and 3) the clinical phenomenology and pathophysiology of narcolepsy. The similarities and differences between the clinical features and pathophysiologic mechanisms involved in narcolepsy and DLB will be reviewed. Narcolepsy provides a reasonable framework, albiet imperfect, for understanding many of the clinical and pathophysiologic aspects of DLB. Further exploration of the similarities and differences between narcolepsy and DLB may provide insights into improving management of some of the more problematic clinical features of DLB.

060 Impaired color discrimination is associated with hallucinations in dementia with lewy bodies

IntroductionEmerging evidence indicates that color discrimination impairments can predict the development of dementia across a range of prodromal Lewy body conditions. However, color vision deficits are not seen uniformly in patients with Dementia with Lewy Bodies (DLB), suggesting a more nuanced association. Visual hallucinations(VH) represent a discriminating feature of DLB, and recent evidence implicates visual pathway dysfunction as a significant contributor to this phenomenon. We therefore hypothesized that color impairment will more closely associate with VH in DLB rather than general cognition.MethodsIn this study, we examined the relationship between color vision impairment and VH, along with other clinical and neuropsychological features in 24 patients with DLB alongside 25 age-matched controls. Color discrimination was assessed using the Farnsworth-Munsell-100 Hue (FM-100) test.ResultsColor discrimination impairment was seen in 16/24 DLB participants (67%) with a higher error score relative to controls(p=0.001). We demonstrate for the first time a strong association between color discrimination errors and both the presence and severity of VH in DLB based on clinician-derived(p=0.008) and questionnaire-derived(p=0.03) measures. Correlation with clinical and neuropsychological variables revealed that color discrimination is significantly related to visuospatial impairment(p=0.02) but not to global measures of cognition, motor severity, age or disease duration. Factor analysis confirmed a unique relationship between color discrimination, visual hallucinations and visuospatial function.ConclusionOur results suggest that color impairments may be a specific biomarker of visual hallucinations and associated visuoperceptual deficits in evolving Lewy body disorders rather than dementia per se and thus providing insight into a shared pathophysiological substrate.

093 How to diagnose lewy body dementia? Prevalence and underlying relationship between clinical and neuropsychological features of DLB

IntroductionDespite its importance for management, prognostication and selection of patients for clinical trials, the diagnosis of Dementia with Lewy Bodies (DLB) remains challenging. Complicating this is a recent change in the diagnostic criteria which has arguably shifted the expected phenotype of DLB patients. In this study we aimed to characterize and examine the relationship between cognitive and clinical diagnostic variables in DLB patients to uncover latent symptom clusters that may streamline future diagnostic approaches in the clinic.MethodsThe clinical and neuropsychological profile of 27 prospectively recruited participants diagnosed with probable DLB and 25 age-matched controls was characterized according to the most recent consensus criteria.Symptoms were scored using a novel combination of established clinical and research instruments.ResultsWe demonstrate comparable sensitivity of formal neuropsychological testing and bedside screening tools (MOCA/MMSE) for identifying domain-specific differences between controls and patients(p&lt;0.001). Optimal sensitivity thresholds for diagnosis of Parkinsonism (88.9%) were explored yielding a prevalence range of 50%-90% within our cohort.Factor analysis using all core and supportive features of the diagnostic criteria identified 6 independent factors accounting for 81% of the total variance. Unique relationships identified included between hallucinations and fluctuations and excessive daytime somnolence; between REM sleep behavior disorder and orthostatic hypotension; and Parkinsonism and urinary disturbance. ‘Prodromal’ symptoms including autonomic and early neuropsychiatric features are represented in the remaining factors.ConclusionParsimonious delineation of clinical variables using identified symptom clusters can aid DLB diagnosis.Clusters are also used to highlight latent pathological relationships. Appropriate instruments and thresholds for detecting dementia and core and suggestive features are presented.

Clinical profiles of late-onset psychiatric patients exhibiting incidental REM sleep without atonia.

Rapid eye movement (REM) sleep without atonia (RWA), which is a hallmark of REM sleep behavior disorder (RBD) on polysomnography (PSG), may represent specific characteristics of prodromal Parkinson's disease (PD)/dementia with Lewy bodies (DLB), even when dream-enactment behavior is absent. We investigated the clinical profiles associated with PD/DLB in late-onset psychiatric patients exhibiting incidental RWA. Among patients who underwent PSG in our psychiatric ward, eight with incidental RWA, nine with idiopathic RBD, and seven with PD or DLB who had preceding RBD were included. Clinical variables, including the percentage of RWA in the total REM sleep (%RWA), were compared among the three groups. The frequency of depressive disorders as a primary psychiatric diagnosis and antidepressant usage were significantly higher in the incidental RWA group than in the other groups. There were no differences in the prevalence of supportive features of DLB among the three groups. The median %RWA was significantly lower in the incidental RWA group than in the other groups. Although the cardiac 123I-metaiodobenzylguanidine uptake was significantly higher in the incidental RWA group compared with the other groups, the groups showed overlap in the specific binding ratios on dopamine transporter imaging. All patients in the three groups exhibited cingulate island sign ratios on brain perfusion single-photon emission computed tomography within a threshold of 0.281, which is the optimal cut-off value for a diagnosis of DLB. In this series, late-onset psychiatric patients with incidental RWA partially shared common clinical profiles with idiopathic RBD and PD/DLB.