Utility of neuropsychiatric tools in the differential diagnosis of dementia with Lewy bodies and Alzheimer's disease: quantitative and qualitative findings

Psychosis in Neurodegenerative Dementias: A Systematic Comparative Review

Background

Psychosis, characterized by delusions and/or hallucinations, is frequently observed during the progression of Alzheimer's disease (AD) and other neurodegenerative dementias (ND) (i.e., dementia with Lewy bodies (DLB), and frontotemporal dementia (FTD)) and cause diagnostic and management difficulties.

Objective

This review aims at presenting a concise and up-to-date overview of psychotic symptoms that occur in patients with ND with a comparative approach.

Methods

A systematic review was conducted following the PRISMA guidelines. 98 original studies investigating psychosis phenotypes in neurodegenerative dementias were identified (40 cohort studies, 57 case reports).

Results

Psychosis is a frequently observed phenomenon during the course of ND, with reported prevalence ranging from 22.5% to 54.1% in AD, 55.9% to 73.9% in DLB, and 18% to 42% in FTD. Throughout all stages of these diseases, noticeable patterns emerge depending on their underlying causes. Misidentification delusions (16.6-78.3%) and visual hallucinations (50-69.6%) are frequently observed in DLB, while paranoid ideas and somatic preoccupations seem to be particularly common in AD and FTD, (respectively 9.1-60.3% and 3.10-41.5%). Limited data were found regarding psychosis in the early stages of these disorders.

Conclusions

Literature data suggest that different ND are associated with noticeable variations in psychotic phenotypes, reflecting disease-specific tendencies. Further studies focusing on the early stages of these disorders are necessary to enhance our understanding of early psychotic manifestations associated with ND and help in differential diagnosis issues.

The frequency of psychotic symptoms in types of dementia: a systematic review

The frequency of psychotic symptoms in older adults is high, mainly in neurocognitive cognitions of the most varied etiologies.

Objectives

This study aimed to review the studies that analyze the frequency of the types of delusions, hallucinations, and misidentifications in dementia conditions of different etiologies.

Methods

A systematic review was conducted on August 9, 2021, in the PubMed, PsycInfo, Embase, Web of Science, and Scopus databases with the following descriptors: (dementia OR alzheimer disease OR dementia with Lewy bodies OR frontotemporal dementia OR mixed dementia OR vascular dementia OR major neurocognitive disorder OR parkinson disease dementia) AND (psychotic symptoms OR psychosis OR hallucinations OR delusions OR psychopathology OR misidentification) AND (prevalence OR epidemiology).

Results

A total of 5,077 articles were found, with a final inclusion of 35. The overall frequency of psychotic symptoms ranged from 34 to 63% in dementia conditions of the most varied etiologies. Alzheimer's disease (AD) presents more delusions and hallucinations and has a higher frequency regarding the presence of misidentifications. On the contrary, Dementia with Lewy bodies (DLB) seems to present more hallucinations, even auditory, when compared to the other dementias, concomitantly with delusions. Vascular and frontotemporal dementia present fewer psychotic symptoms than DLB and AD.

Conclusions

We identified a gap in the literature on the description of the psychotic symptoms of dementia, mainly in those of non-AD etiologies. Studies that assess the neuropsychiatric symptoms of dementias deeply might contribute in a more definite manner to the causal diagnosis of dementia.

Psychosis as a Treatment Target in Dementia: A Roadmap for Designing Interventions

Psychotic phenomena are among the most severe and disruptive symptoms of dementias and appear in 30% to 50% of patients. They are associated with a worse evolution and great suffering to patients and caregivers. Their current treatments obtain limited results and are not free of adverse effects, which are sometimes serious. It is therefore crucial to develop new treatments that can improve this situation. We review available data that could enlighten the future design of clinical trials with psychosis in dementia as main target. Along with an explanation of its prevalence in the common diseases that cause dementia, we present proposals aimed at improving the definition of symptoms and what should be included and excluded in clinical trials. A review of the available information regarding the neurobiological basis of symptoms, in terms of pathology, neuroimaging, and genomics, is provided as a guide towards new therapeutic targets. The correct evaluation of symptoms is transcendental in any therapeutic trial and these aspects are extensively addressed. Finally, a critical overview of existing pharmacological and non-pharmacological treatments is made, revealing the unmet needs, in terms of efficacy and safety. Our work emphasizes the need for better definition and measurement of psychotic symptoms in dementias in order to highlight their differences with symptoms that appear in non-dementing diseases such as schizophrenia. Advances in neurobiology should illuminate the development of new, more effective and safer molecules for which this review can serve as a roadmap in the design of future clinical trials.

Criteria for Psychosis in Major and Mild Neurocognitive Disorders: International Psychogeriatric Association (IPA) Consensus Clinical and Research Definition

Psychosis is common among individuals with neurocognitive disorders, is difficult to manage, and causes considerable burden and stress to patients and caregivers. Developing effective treatments is a substantial unmet medical need but research has been slowed by the need for updated consensus diagnostic criteria. To address this need, the International Psychogeriatrics Association initiated a process to develop criteria for clinical use, research, and treatment development efforts. The process included clinical, regulatory, and industry stakeholders as well as input from a global network of experts in geriatric psychiatry responding to two surveys (N = 336). Results from the consensus process confirmed that clinicians wanted elaboration of aspects of the definition proposed by Jeste and Finkel in 2000 to ensure that the criteria are applied appropriately. Based on discussions, the survey, and emerging research, criteria were revised to apply to psychosis occurring with all major and mild neurocognitive disorders. Other important changes include providing examples of hallucinations and delusions and clarifying time course, impact, and exclusionary criteria. This definition of psychosis in major and mild neurocognitive disorders can be used to advance many types of research including development of much needed pharmacologic and nonpharmacologic interventions for psychosis in patients with neurocognitive disorders.

Differential changes in visual and auditory event-related oscillations in dementia with Lewy bodies

OBJECTIVE

Aside from the cognitive impairment, patients with dementia with Lewy bodies (DLB) have a high frequency of visual hallucinations and a number of other vision-related symptoms, whereas auditory hallucinations are less frequent. To better understand the differential dysfunction of the visual network in DLB, we compared auditory and visual event-related potentials and oscillations in patients with DLB.

METHODS

Event-related potentials elicited by visual and auditory oddball tasks were recorded in 23 patients with DLB and 22 healthy controls and analyzed in time and time-frequency domain.

RESULTS

DLB patients had decreased theta band activity related to both early sensory and later cognitive processing in the visual, but not in the auditory task. Patients had lower delta and higher alpha and beta bands power related to later cognitive processing in both auditory and visual tasks.

CONCLUSIONS

In DLB visual event-related oscillations are characterized by a decrease in theta and lack of inhibition in alpha bands.

SIGNIFICANCE

Decreased theta and a lack of inhibition in alpha band power might be an oscillatory underpinning of some classical DLB symptoms such as fluctuations in attention and high-level visual disturbances and a potential marker of dysfunction of the visual system in DLB.

Auditory and visual hallucination prevalence in Parkinson's disease and dementia with Lewy bodies: a systematic review and meta-analysis

BACKGROUND

Non-motor features of Parkinson's disease (PD) and dementia with Lewy bodies (DLB), such as auditory hallucinations (AH), contribute to disease burden but are not well understood.

METHODS

Systematic review and random-effects meta-analyses of studies reporting AH associated with PD or DLB. Prevalence of visual hallucinations (VH) in identified studies meeting eligibility criteria were included in meta-analyses, facilitating comparison with AH. Synthesis of qualitative descriptions of AH was performed. PubMed, Web of Science and Scopus databases were searched for primary journal articles, written in English, published from 1970 to 2017. Studies reporting AH prevalence in PD or DLB were screened using PRISMA methods.

RESULTS

Searches identified 4542 unique studies for consideration, of which, 26 met inclusion criteria. AH pooled prevalence in PD was estimated to be 8.9% [95% confidence interval (CI) 5.3-14.5], while in DLB was estimated to be 30.8% (±23.4 to 39.3). Verbal hallucinations, perceived as originating outside the head, were the most common form of AH. Non-verbal AH were also common while musical AH were rare. VH were more prevalent, with an estimated pooled prevalence in PD of 28.2% (±19.1 to 39.5), while in DLB they were estimated to be 61.8% (±49.1 to 73.0). Meta-regression determined that the use of validated methodologies to identify hallucinations produced higher prevalence estimates.

CONCLUSIONS

AH and VH present in a substantial proportion of PD and DLB cases, with VH reported more frequently in both conditions. Both AH and VH are more prevalent in DLB than PD. There is a need for standardised use of validated methods to detect and monitor hallucinations.

Neuropsychiatric Symptoms as Predictors of Clinical Course in Neurodegeneration. A Longitudinal Study

Background: To study the extent to which neuropsychiatric symptoms (NPS) influence the cognitive and functional decline in frontotemporal degeneration (FTD) and Alzheimer’s disease (AD).

Methods: We assessed the progression of NPS and their influence on cognitive and functional progression in a group of FTD (n = 36) and AD patients (n = 47) at two different stages of the disease (2.5 years). A standardized scale was used to assess NPS—the Columbia University Scale for Psychopathology in Alzheimer’s Disease (CUSPAD)—which tracks different symptoms including depression, psychotic symptoms, as well as sleep and conduct problems. In addition, in a subsample of patients (AD n = 14 and FTD n = 14), we analyzed another group of NPS by using the Neuropsychiatric Inventory (NPI). Cognitive declines were tracked by using the Montreal Cognitive Assessment (MoCA) and the Mini-Mental State Examination (MMSE), while functionality was tracked by using the Lawton scale and the Barthel Index.

Results: The presence of NPS impacts cognitive and functional decline in both groups of patients 2.5 years after disease onset. However, we observed a dissociable profile of the affectation of NPS in each group. In the AD group, results indicate that the progression of depressive symptoms and sleep problems predict cognitive and functional decline. In contrast, the progression of a mixed group of NPS, including conduct problems and delusions, predicts cognitive and functional decline in FTD.

Conclusion: The presence of NPS has a critical impact on the prediction of cognitive decline in FTD and AD patients after 2.5 years of disease progression. Our results demonstrate the importance of assessing different types of NPS in neurodegenerative disorders which, in turn, predict disease progression. Future studies should assess the role of NPS in predicting different neurocognitive pathways and in neurodegeneration.

Delusions in Patients with Dementia with Lewy Bodies and the Associated Factors

Objective

Delusions are common neuropsychiatric symptoms in patients with dementia with Lewy bodies (DLB). The aim of this study was to investigate the associated factors of delusions in patients with DLB.

Method

A retrospective study of outpatients with DLB registered in a regional hospital's database was performed. The associated factors including cognitive performance, clinical features, vascular risk factors, and neuropsychiatric symptoms between delusional and nondelusional patients with DLB were compared.

Results

Among 207 patients with DLB, 106 (51.2%) were delusional and 101 (48.8%) were not. Delusion of other persons are stealing was the most common symptom (35.3%). The delusional group had a significantly higher diagnostic rate of probable than possible DLB, higher disease severity, poorer cognitive performance, more severe neuropsychiatric symptoms, and higher caregiver burden (all p < 0.05). In addition, the delusional group had a significantly lower frequency of diabetes compared to the nondelusional group (odds ratio = 0.28, p < 0.001).

Conclusion

Delusion of other persons are stealing was the most common delusional symptom. The patients with DLB who presented with delusions had poorer cognitive function and more severe neuropsychiatric symptoms. A novel finding is that the DLB patients with diabetes had a lower frequency of delusions.

Gender difference in the association and presentation of visual hallucinations in dementia with Lewy bodies: a cross-sectional study

OBJECTIVE

Visual hallucinations (VHs) are among the most striking features of dementia with Lewy bodies (DLB). We investigated gender differences in the association and presentation of VHs in DLB.

METHODS

A cross-sectional analysis of baseline data from a prospective, longitudinal study on dementia was performed. Cumulative frequency, 1-month frequency, and phenomenology of VHs were summarized and compared between female and male patients with DLB. Gender differences in the factors associated with VHs were investigated in patients with and without hallucinations.

RESULTS

A total of 152 patients including 65 (42.8%) women and 87 (57.2%) men were analyzed. The cumulative and 1-month frequencies of VHs were 60% and 55.4%, respectively, in women and 44.8% and 41.4%, respectively, in men. Adjusting for age and disease severity resulted in the inclusion of more women in the VH group [odds ratio (OR) = 2.33, p = 0.028)] than in the non-VH group. In female participants, older age (OR = 9.16, p = 0.003) and higher neuropsychiatric inventory score (OR = 4.89, p = 0.009) were associated with VHs, whereas in male participants, more severe dementia stage (clinical dementia rating 2-3 versus clinical dementia rating 0.5, OR = 6.22, p = 0.008) and higher rates of using antipsychotics (OR = 9.64, p = 0.047) were associated with VHs.

CONCLUSION

The frequencies of 1-month and cumulative VHs were high in DLB, which indicated a high prevalence as well as a high persistency of VHs in DLB. The patterns of factors associated with VHs differed between female and male patients. Copyright © 2017 John Wiley & Sons, Ltd.

Visual hallucinations in Alzheimer's disease is significantly associated with clinical diagnostic features of dementia with Lewy bodies

Visual hallucinations (VHs) are among the most striking features of dementia with Lewy bodies (DLB). Given that Lewy body pathology is frequently observed in the brains of patients with AD, we aimed to study factors associated with VHs in AD and examine their association with DLB features. This cross-sectional study enrolled a consecutive series of AD patients who visited the dementia clinic of a regional hospital. Clinically diagnosed possible or probable DLB cases were excluded. VH frequency and associated factors including age, sex, education, disease severity, DLB features, vascular risk factors, cognitive function, and neuropsychiatric symptoms were compared between AD patients with VHs (VH+) and those without VHs (VH−). Among a total of 295 patients analyzed, 42 (14.2%) had VHs. After adjusting for age, sex, and disease severity, DLB features including fluctuations in cognition scores, rapid-eye-movement behavioral disorder (RBD), and severe neuroleptic sensitivity were more frequent in the VH+ group. Furthermore, depression score, total Neuropsychiatric Inventory (NPI) score, and total caregiver burden score as assessed by the NPI were higher in the VH+ group. Among neuropsychiatric symptoms, delusions, hallucinations in the non-visual domains, anxiety, and disinhibition were more frequent in the VH+ group. Conversely, none of the vascular risk factors (VRFs) or cognitive domains of the Cognitive Abilities Screening Instrument (CASI) was associated with VHs in AD. In summary, VHs, albeit occurring at a low rate, had a high impact on AD. Diagnostic features of DLB, including fluctuations, RBD, and severe neuroleptic sensitivity were significantly associated with VHs in AD. AD patients with VHs tended to have more severe neuropsychiatric symptoms and greater caregiver burden.

Clinical Spectrum, Risk Factors, and Behavioral Abnormalities among Dementia Subtypes in a North Indian Population: A Hospital-Based Study

Background

As variability in the clinical profile of dementia subtypes had been reported with regional differences across the world, we conducted a retrospective hospital-based study in a North Indian population.

Methods

We retrieved patient records from 2007 to 2014 for details of clinical evaluation, diagnosis, neuroimaging, biochemical investigations, and follow-up of 1,876 patients with dementia (PwD), and the data were analyzed using descriptive statistics.

Results

Of the total PwD, Alzheimer disease (AD) accounted for 30% followed by vascular dementia (VaD) 26%, mixed dementia (MD) 21%, Parkinson-related dementia 11%, frontotemporal dementia (FTD) 7%, and infective dementia 5%. Of all PwD excluding the infective group (n = 1,777), 63% were men, 39% were from rural areas, 87% had behavioral abnormalities along with cognitive deficits, and 73% had impaired ADLs. Among dementia subtypes, a positive family history, cardiovascular and metabolic risk factors, and behavioral abnormalities were found to be distributed. However, there existed a predominance of specific behavioral pattern in each subtype. The mean duration of follow-up varied from 2.9 ± 2.3 (VaD) to 3.6 ± 2.1 (AD) and greater than 30% were found to be stable on treatment (except in dementia with Lewy body).

Conclusions

This large hospital-based study provides a distribution pattern and clinical spectrum of dementia subtypes in a North Indian population.

The need for harmonisation and innovation of neuropsychological assessment in neurodegenerative dementias in Europe: consensus document of the Joint Program for Neurodegenerative Diseases Working Group

Cognitive, behavioural, and functional assessment is crucial in longitudinal studies of neurodegenerative dementias (NDD). Central issues, such as the definition of the study population (asymptomatic, at risk, or individuals with dementia), the detection of change/decline, and the assessment of relevant outcomes depend on quantitative measures of cognitive, behavioural, and functional status.

Currently, we are far from having available reliable protocols and tools for the assessment of dementias in Europe. The main problems are the heterogeneity of the tools used across different European countries, the lack of standardisation of administration and scoring methods across centres, and the limited information available about the psychometric properties of many tests currently in widespread use. This situation makes it hard to compare results across studies carried out in different centres, thus hampering research progress, in particular towards the contribution to a “big data” common data set.

We present here the results of a project funded by the Joint Program for Neurodegenerative Diseases (JPND) and by the Italian Ministry of Health. The project aimed at providing a consensus framework for the harmonisation of assessment tools to be applied to research in neurodegenerative disorders affecting cognition across Europe. A panel of European experts reviewed the current methods of neuropsychological assessment, identified pending issues, and made recommendations for the harmonisation of neuropsychological assessment of neurodegenerative dementias in Europe.

A consensus was achieved on the general recommendations to be followed in developing procedures and tools for neuropsychological assessment, with the aim of harmonising tools and procedures to achieve more reliable data on the cognitive-behavioural examination. The results of this study should be considered as a first step to enhancing a common view and practise on NDD assessment across European countries.

Phenotypic differences based on staging of Alzheimer's neuropathology in autopsy-confirmed dementia with Lewy bodies

INTRODUCTION

The goal was to compare subgroups of dementia with Lewy Bodies (DLB) using neuropathological measures to differentiate 'pure' Lewy body (LB) dementia from 'mixed' DLB [co-occurring LB and Alzheimer's disease (AD) pathology] to facilitate diagnostic decision-making and future development of interventions based on predicted type(s) of neuropathology. Studies comparing these groups are rare relative to those differentiating 'pure' AD and all-cause DLB, and are limited by insufficient sample size, brief cognitive batteries, and/or absence of autopsy confirmation. To address these limitations, we assessed cognition and other features in a large, autopsy-confirmed DLB sample using an extensive neuropsychological battery.

METHODS

Subjects from an AD research center autopsy series satisfying DLB pathology criteria were divided by an AD neuropathology index into DLB-LB (Braak stage 0-3) (n = 38) and DLB-AD (Braak stage 4-6) (n = 41) and compared on baseline variables from chart reviews and standardized measures.

RESULTS

DLB-LB subjects were more impaired on visuospatial constructions, visual conceptual reasoning, and speed of processing, but less impaired on verbal memory and confrontation naming. All-type hallucinations occurred more frequently in DLB-LB, while delusions were common in both groups. Groups were similar in education and age at onset, and in baseline age, dementia severity, and functional capacity.

CONCLUSION

Salient findings included greater impairment on visual tasks and speed of processing and more frequent reports of all-type hallucinations in DLB-LB compared to DLB-AD. Relatively intact confrontation naming in DLB-LB and no differences in reported delusions were of note. Identifying differences in phenotypic features can improve prediction of underlying neuropathology.

Neuropsychiatric Symptoms in Parkinson's Disease Dementia Are More Similar to Alzheimer's Disease than Dementia with Lewy Bodies: A Case-Control Study

Background and purpose

Previous studies on the clinical and pathological manifestations of Parkinson’s disease dementia (PDD) have reported findings more similar to dementia with Lewy bodies (DLB) than to Alzheimer’s disease (AD). The aim of this study was to investigate the neuropsychiatric symptoms of PDD compared to DLB and AD.

Methods

We conducted a retrospective case-control study on 125 newly diagnosed consecutive PDD patients and age- and dementia stage-matched controls with either DLB (N = 250) or AD (N = 500) who visited the same hospital over the same period. For each case and control, neuropsychiatric symptoms were assessed using the Neuropsychiatric Inventory (NPI).

Results

Overall, 513 (58.6%) patients were female and 362 (41.4%) were male. Comparisons of clinical data revealed that the PDD group, similar to the AD group, had a lower NPI total score, NPI caregiver burden score, and rate of antipsychotic use (all p < 0.001) than the DLB group. One or more psychiatric symptoms were reported in 95.2% of the PDD, 99.2% of the DLB, and 96.8% of the AD patients. The PDD group had lower subscores in the items of delusions, hallucinations, agitation, anxiety, irritation, aberrant motor behavior compared to the DLB group. Severe neuropsychiatric symptoms among all dementia patients were associated with younger age, more advanced stage, and a diagnosis of DLB.

Conclusion

Neuropsychiatric symptoms in PDD were more like those in AD than in DLB. Severe neuropsychiatric symptoms in degenerative dementia were associated with younger age, more advanced stage of dementia, and a diagnosis of DLB.

Neuropsychiatric Symptoms in Posterior Cortical Atrophy and Alzheimer Disease

BACKGROUND

Posterior cortical atrophy (PCA) is a rare neurodegenerative syndrome characterized by early progressive visual dysfunction in the context of relative preservation of memory and a pattern of atrophy mainly involving the posterior cortex. The aim of the present study is to characterize the neuropsychiatric profile of PCA.

METHODS

The Neuropsychiatric Inventory was used to assess 12 neuropsychiatric symptoms (NPS) in 28 patients with PCA and 34 patients with typical Alzheimer disease (AD) matched by age, disease duration, and illness severity.

RESULTS

The most commonly reported NPS in both groups were depression, anxiety, apathy, and irritability. However, aside from a trend toward lower rates of apathy in patients with PCA, there were no differences in the percentage of NPS presented in each group. All those patients presenting visual hallucinations in the PCA group also met diagnostic criteria for dementia with Lewy bodies (DLB). Auditory hallucinations were only present in patients meeting diagnosis criteria for DLB.

CONCLUSION

Prevalence of the 12 NPS examined was similar between patients with PCA and AD. Hallucinations in PCA may be helpful in the differential diagnosis between PCA-AD and PCA-DLB.

Comparisons of clinical symptoms in biomarker-confirmed Alzheimer's disease, dementia with Lewy bodies, and frontotemporal dementia patients in a local memory clinic

BACKGROUND

There has been no previous Chinese study that differentiated the clinical symptoms among biomarker-confirmed Alzheimer's disease (AD), dementia with Lewy bodies (DLB) and frontotemporal dementia (FTD). The objective of this study was to compare the cognitive, behavioural, and neuropsychiatric symptoms in biomarker-confirmed AD, DLB, and FTD patients.

METHODS

We recruited 30 patients (14 AD, 7 DLB, 9 FTD) who presented to the memory clinic at Queen Mary Hospital from 1 January 2007 to 31 December 2013. AD was diagnosed according to the National Institution of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association criteria with cerebrospinal fluid biomarkers (tau, phosphorylated tau, and amyloid β-42) fulfilling locally determined cut-off values for AD. DLB was diagnosed based on the McKeith diagnostic criteria. The behavioural variant of FTD was diagnosed based on the revised diagnostic criteria proposed by the International bvFTD Criteria Consortium, and language variant FTD was diagnosed based on the latest published criteria. In addition, patients with DLB and FTD had typical imaging features on single-photon emission computed tomography or (18) fludeoxyglucose-positron emission tomography, either with or without Pittsburgh Compound B imaging, which supported their diagnoses. Data on patient characteristics including demographics, presenting clinical features, Mini-Mental State Examination, clinical dementia ratings, and neuropsychiatry inventory scores were collected.

RESULTS

There were no differences in age, education level, dementia severity, and duration of symptoms before presentation among the three subgroups of patients. All patients had amnesia symptoms, which were not statistically significant. Apraxia was most common in AD. While 83% of the patients were affected by behavioural and neuropsychiatric symptoms of dementia, behavioural disinhibition and decline in executive function were most common in FTD patients. Recurrent hallucinations, fluctuation of consciousness, parkinsonism, and rapid eye movement sleep behaviour disorder were most common in DLB.

CONCLUSION

Memory impairment and apathy are not useful discriminative symptoms in diagnosing AD, DLB, and FTD. Apraxia favours AD. Hallucinations, particularly well-formed visual hallucinations, favour DLB. Overall, behavioural and neuropsychiatric symptoms of dementia symptoms are common among the three groups of dementia patients.