Efficacy of rivastigmine in dementia with Lewy bodies: a randomised, double-blind, placebo-controlled international study

Visual dysfunction in dementia with Lewy bodies

PURPOSE OF REVIEW

To review the literature on visual dysfunction in dementia with Lewy bodies (DLB), including its mechanisms and clinical implications.

RECENT FINDINGS

Recent studies have explored novel aspects of visual dysfunction in DLB, including visual texture agnosia, mental rotation of 3-dimensional drawn objects, and reading fragmented letters. Recent studies have shown parietal and occipital hypoperfusion correlating with impaired visuoconstruction performance. While visual dysfunction in clinically manifest DLB is well recognized, recent work has focused on prodromal or mild cognitive impairment (MCI) due to Lewy body pathology with mixed results. Advances in retinal imaging have recently led to the identification of abnormalities such as parafoveal thinning in DLB. Patients with DLB experience impairment in color perception, form and object identification, space and motion perception, visuoconstruction tasks, and illusions in association with visual cortex and network dysfunction. These symptoms are associated with visual hallucinations, driving impairment, falls, and other negative outcomes.

Cognitive dysfunction in animal models of human lewy-body dementia

Cognitive impairments are a common feature of synucleinopathies such as Parkinson's Disease Dementia and Dementia with Lewy Bodies. These pathologies are characterized by accumulation of Lewy bodies and Lewy neurites as well as neuronal cell death. Alpha-synuclein is the main proteinaceous component of Lewy bodies and Lewy neurites. To model these pathologies in vivo, toxins that selectively target certain neuronal populations or different means of inducing alpha-synuclein aggregation can be used. Alpha-synuclein accumulation can be induced by genetic manipulation, viral vector overexpression or the use of preformed fibrils of alpha-synuclein. In this review, we summarize the cognitive impairments associated with different models of synucleinopathies and relevance to observations in human diseases.

Episodic Visual Hallucinations, Inference and Free Energy

Understandings of how visual hallucinations appear have been highly influenced by generative approaches, in particular Friston's Active Inference conceptualization. Their core proposition is that these phenomena occur when hallucinatory expectations outweigh actual sensory data. This imbalance occurs as the brain seeks to minimize informational free energy, a measure of the distance between predicted and actual sensory data in a stationary open system. We review this approach in the light of old and new information on the role of environmental factors in episodic hallucinations. In particular, we highlight the possible relationship of specific visual triggers to the onset and offset of some episodes. We use an analogy from phase transitions in physics to explore factors which might account for intermittent shifts between veridical and hallucinatory vision. In these triggered forms of hallucinations, we suggest that there is a transient disturbance in the normal one-to-one correspondence between a real object and the counterpart perception such that this correspondence becomes between the real object and a hallucination. Generative models propose that a lack of information transfer from the environment to the brain is one of the key features of hallucinations. In contrast, we submit that specific information transfer is required at onset and offset in these cases. We propose that this transient one-to-one correspondence between environment and hallucination is mediated more by aberrant discriminative than by generative inference. Discriminative inference can be conceptualized as a process for maximizing shared information between the environment and perception within a self-organizing nonstationary system. We suggest that generative inference plays the greater role in established hallucinations and in the persistence of individual hallucinatory episodes. We further explore whether thermodynamic free energy may be an additional factor in why hallucinations are temporary. Future empirical research could productively concentrate on three areas. Firstly, subjective perceptual changes and parallel variations in brain function during specific transitions between veridical and hallucinatory vision to inform models of how episodes occur. Secondly, systematic investigation of the links between environment and hallucination episodes to probe the role of information transfer in triggering transitions between veridical and hallucinatory vision. Finally, changes in hallucinatory episodes over time to elucidate the role of learning on phenomenology. These empirical data will allow the potential roles of different forms of inference in the stages of hallucinatory episodes to be elucidated.

Efficacy and safety of donepezil in patients with dementia with Lewy bodies: results from a 12-week multicentre, randomised, double-blind, and placebo-controlled phase IV study

BACKGROUND

Donepezil has been approved in Japan for the treatment of dementia with Lewy bodies (DLB) based on clinical trials showing its beneficial effects on cognitive impairment. This phase IV study evaluated the efficacy of donepezil by focusing on global clinical status during a 12-week double-blind phase.

METHODS

Patients with probable DLB were randomly assigned to the placebo (n = 79) or 10 mg donepezil (n = 81) groups. The primary endpoint was changes in global clinical status, assessed using the Clinician's Interview-Based Impression of Change plus Caregiver Input (CIBIC-plus). We also assessed four CIBIC-plus domains (general condition, cognitive function, behaviour, and activities of daily living) and changes in cognitive impairment and behavioural and neuropsychiatric symptoms measured using the Mini-Mental State Examination (MMSE) and the Neuropsychiatric Inventory (NPI), respectively.

RESULTS

Although donepezil's superiority was not shown in the global clinical status, a significant favourable effect was detected in the cognitive domain (P = 0.006). MMSE scores improved in the donepezil group after adjustments in post hoc analysis (MMSE mean difference, 1.4 (95% confidence interval (CI), 0.42-2.30), P = 0.004). Improvements in NPIs were similar between the groups (NPI-2: -0.2 (95% CI, -1.48 to 1.01), P = 0.710; NPI-10: 0.1 (95% CI, -3.28 to 3.55), P = 0.937).

CONCLUSION

The results support the observation that the efficacy of 10 mg donepezil in improving cognitive function is clinically meaningful in DLB patients. The evaluation of global clinical status might be affected by mild to moderate DLB patients enrolled in this study. No new safety concerns were detected.

Treatment of Apathy in Parkinson's Disease and Implications for Underlying Pathophysiology

Apathy is a prevalent and highly debilitating non-motor symptom of Parkinson's disease (PD) that is often overlooked in clinical practice due to its subtle nature. This review aims to provide a comprehensive overview of the current evidence for the treatment of apathy in PD, highlighting recent advancements and emerging therapeutic avenues. In this review, we analyse a diverse array of treatment strategies for apathy in PD, including pharmacological interventions, non-pharmacological approaches, and emerging neuromodulation techniques. We evaluate the efficacy, safety, and limitations of established pharmacotherapies, such as dopaminergic agents, antidepressants, and cognitive enhancers. Additionally, we examine the promising role of non-pharmacological interventions, encompassing psychotherapies and behavioural interventions, in ameliorating apathetic symptoms. Furthermore, this review explores the effects of neuromodulation techniques on apathy, including the modulation of apathy via deep brain stimulation and emerging data on the potential influence of transcranial magnetic stimulation (TMS) on apathy in PD. Ultimately, a deeper understanding of effective treatment strategies for apathy has the potential to significantly improve the quality of life and overall well-being of individuals living with PD.

The effects of rivastigmine on neuropsychiatric symptoms in the early stages of Parkinson's disease: A systematic review

BACKGROUND AND PURPOSE

Neuropsychiatric symptoms including depression, apathy and psychosis occur frequently in patients with Parkinson's disease. A subgroup of patients develop cognitive impairment, which may increase the risk of falls due to reduced attention. The acetylcholinesterase inhibitor rivastigmine is beneficial in Parkinson's disease dementia, but whether the use of rivastigmine is effective earlier in the disease course is unclear. The aim of this systematic review was to assess the evidence for rivastigmine in the treatment of neuropsychiatric symptoms in Parkinson's disease without dementia.

METHODS

Embase, Medline, PsychINFO, Cochrane CENTRAL, NGLC, National Institute for Health and Care Excellence Evidence and medRxiv.org were searched for studies with terms relating to population (Parkinson's disease) and intervention (rivastigmine). Of 1922 references identified, 358 were duplications. Following title and abstract review, 1331 articles were excluded. After full-text review, nine articles remained.

RESULTS

Outcomes were heterogenous, therefore, the results are presented in narrative form. The articles included six randomized controlled trials, two open-label trials and one case series. Outcome measures included: time to develop psychosis; frequency of rapid eye movement sleep behaviour disorder (RBD) episodes; apathy; gait variability; falls; cognitive ability; Neuropsychiatric Inventory score; and regional spontaneous brain activity.

CONCLUSIONS

There is evidence that rivastigmine is beneficial for RBD and apathy in Parkinson's disease patients without dementia. There is high level evidence that rivastigmine reduces falls, which may be due to improved attention. The impact of rivastigmine on psychotic symptoms is less clear, but is supported by current theoretical models which involve acetylcholine dysfunction in the generation of visual hallucinations in Parkinson's disease.

Insights into the management of Lewy body dementia: a scoping review

Lewy body dementia (LBD) is situated at the convergence of neurodegenerative disorders, posing an intricate and diverse clinical dilemma. The accumulation of abnormal protein in the brain, namely, the Lewy body causes disturbances in typical neural functioning, leading to a range of cognitive, motor, and mental symptoms that have a substantial influence on the overall well-being and quality of life of affected individuals. There is no definitive cure for the disease; however, several nonpharmacological and pharmacological modalities have been tried with questionable efficacies. The aim of this study is to figure out the role of different interventional strategies in the disease. Donepezil, rivastigmine, memantine, and galantamine were the commonly used drugs for LBD. Together with that, levodopa, antipsychotics, armodafinil, piracetam, and traditional medications like yokukansan were also used, when indicated. Talking about nonpharmacological measures, exercise, physical therapy, multicomponent therapy, occupational therapy, psychobehavioral modification, transcranial stimulation, and deep brain stimulation have been used with variable efficacies. Talking about recent advances in the treatment of LBD, various disease-modifying therapies like ambroxol, neflamapimod, irsenontrine, nilotinib, bosutinib, vodobatinib, clenbuterol, terazosin, elayta, fosgonimeton, and anle138b are emerging out. However, there drugs are still in the different phases of clinical trials and are not commonly used in clinical practice. With the different pharmacological and nonpharmacological modalities we have for treatment of LBD, all of them offer symptomatic relief only. Being a degenerative disease, definite cure of the disease can only be possible with regenerative measures.

Apathy in Lewy body disease and its effects on functional impairment over time

Background and objectives

Apathy strongly affects function in Alzheimer's disease and frontotemporal dementia, however its effect on function in Lewy Body Disease (LBD) has not been well-described. This study aims to (1) examine the prevalence and persistence of apathy in a large, national cohort of well-characterized patients with LBD, and (2) estimate the effect of apathy on function over time.

Methods

Study included 676 participants with mild cognitive impairment (MCI) or dementia in the National Alzheimer's Coordinating Center Uniform Data Set. Participants were followed for an average of 3.4 ± 1.7 years and consistently had a primary diagnosis of LBD. Apathy was defined by clinician judgment, categorized into four mutually exclusive profiles: (1) never apathetic across all visits, (2) at least one but <50% of visits with apathy (intermittent apathy), (3) ≥50% but not all visits with apathy (persistent apathy), and (4) always apathy across all visits. Dementia severity was measured by baseline Clinical Dementia Rating score. Parkinsonism was defined by the presence of bradykinesia, resting tremor, rigidity, gait, and postural instability. Functional impairment was assessed using the Functional Assessment Questionnaire (FAQ).

Results

Baseline characteristics of the sample were: average age = 72.9 ± 6.9, years of education = 15.6 ± 3.4, Mini Mental State Exam (MMSE) = 24.4 ± 5.4, Geriatric Depression Scale (GDS) = 3.8 ± 3.2, FAQ = 12.0 ± 9.1. 78.8% were male and 89% were non-Hispanic white. Prevalence of apathy increased from 54.4% at baseline to 65.5% in year 4. 77% of participants had apathy at some point during follow-up. Independent of cognitive status and parkinsonian features, FAQ was significantly higher in participants with intermittent/persistent and always apathetic than never apathetic. Annual rate of decline in FAQ was faster in participants who were always apathetic than never apathy.

Discussion

In this large national longitudinal cohort of LBD patients with cognitive impairment, apathy was strongly associated with greater functional impairment at baseline and faster rate of decline over time. The magnitude of these effects were clinically important and were observed beyond the effects on function from participants' cognitive status and parkinsonism, highlighting the importance of specifically assessing for apathy in LBD.

Emerging drugs for dementia with Lewy Bodies: a review of Phase II & III trials

INTRODUCTION

Despite faster cognitive decline and greater negative impact on patients and family caregivers, drug development efforts in Dementia with Lewy Bodies (DLB) fall behind those for Alzheimer's Disease (AD). Current off-label drug DLB treatment options are limited to symptomatic agents developed to address cognitive deficits in AD, motor deficits in Parkinson's Disease, or behavioral symptoms in psychiatric disease. Aided by recent improvements in DLB diagnosis, a new focus on the development of disease-modifying agents (DMA) is emerging.

AREAS COVERED

Driven by evidence supporting different pathological mechanisms in DLB and PDD, this review assesses the evidence on symptomatic drug treatments and describes current efforts in DMA development in DLB. Specifically, our goals were to: (1) review evidence supporting the use of symptomatic drug treatments in DLB; (2) review the current DMA pipeline in DLB with a focus on Phase II and III clinical trials; and (3) identify potential issues with the development of DMA in DLB. Included in this review were completed and ongoing drug clinical trials in DLB registered on ClinicalTrials.gov (no time limits set for the search) or disseminated at the 2023 international conference on Clinical Trials in AD. Drug clinical trials registered in non-US clinical trial registries were not included.

EXPERT OPINION

Adoption of current symptomatic drug treatments used off-label in DLB relied on efficacy of benefits in other disorders rather than evidence from randomized controlled clinical trials. Symptoms remain difficult to manage. Several DMA drugs are currently being evaluated as either repurposing candidates or novel small molecules. Continued improvement in methodological aspects including development of DLB-specific outcome measures and biomarkers is needed to move the field of DMA drug development forward.

Pareidolias are a function of visuoperceptual impairment

Pareidolias, or the misperception of ambiguous stimuli as meaningful objects, are complex visual illusions thought to be phenomenologically similar to Visual Hallucination (VH). VH are a major predictor of dementia in Parkinson's Disease (PD) and are included as a core clinical feature in Dementia with Lewy Bodies (DLB). A newly developed Noise Pareidolia Test (NPT) was proposed as a possible surrogate marker for VH in DLB patients as increased pareidolic responses correlated with informant-corroborated accounts of VH. This association could, however, be mediated by visuoperceptual impairment. To understand the drivers of performance on the NPT, we contrasted performances in patient groups that varied both in terms of visuoperceptual ability and rates of VH. N = 43 patients were studied of whom n = 13 had DLB or PD with Dementia (PDD); n = 13 had PD; n = 12 had typical, memory-onset Alzheimer's Disease (tAD); and n = 5 had Posterior Cortical Atrophy (PCA) due to Alzheimer's disease. All patient groups reported pareidolias. Within the Lewy body disorders (PD, DLB, PDD), there was no significant difference in pareidolic response rates between hallucinating and non-hallucinating patients. Visuoperceptual deficits and pareidolic responses were most frequent in the PCA group-none of whom reported VH. Regression analyses in the entire patient cohort indicated that pareidolias were strongly predicted by visuoperceptual impairment but not by the presence of VH. These findings suggest that pareidolias reflect the underlying visuoperceptual impairment of Lewy body disorders, rather than being a direct marker for VH.

Decoding Neurodegeneration: A Comprehensive Review of Molecular Mechanisms, Genetic Influences, and Therapeutic Innovations

Neurodegenerative disorders often acquire due to genetic predispositions and genomic alterations after exposure to multiple risk factors. The most commonly found pathologies are variations of dementia, such as frontotemporal dementia and Lewy body dementia, as well as rare subtypes of cerebral and cerebellar atrophy-based syndromes. In an emerging era of biomedical advances, molecular-cellular studies offer an essential avenue for a thorough recognition of the underlying mechanisms and their possible implications in the patient's symptomatology. This comprehensive review is focused on deciphering molecular mechanisms and the implications regarding those pathologies' clinical advancement and provides an analytical overview of genetic mutations in the case of neurodegenerative disorders. With the help of well-developed modern genetic investigations, these clinically complex disturbances are highly understood nowadays, being an important step in establishing molecularly targeted therapies and implementing those approaches in the physician's practice.

A Systematic Review of Pharmacological Interventions for Apathy in Aging Neurocognitive Disorders

OBJECTIVE

Apathy, a frequent neuropsychiatric symptom in aging neurocognitive disorders, has been associated with cognitive decline and functional disability. Therefore, timely provision of pharmacological interventions for apathy is greatly needed.

DESIGN

A systematical literature review of existing studies was conducted up to 30 May 2023 in several databases (PubMed, PsychInfo, Cochrane, Google Scholar, etc.) that included randomized controlled trials (RCTs) and meta-analyses assessing pharmacological treatments for apathy in aging neurocognitive disorders. The quality of the studies was appraised.

RESULTS

In patients with Alzheimer's Disease (AD), donepezil, galantamine, rivastigmine, methylphenidate, and gingko biloba were proven efficacious for apathy, while rivastigmine, cognitive enhancer IRL752 and piribedil were found to be beneficial in patients with Parkinson's Disease (PD) and agomelatine in patients with Frontotemporal Dementia (FD). The extensive proportion of RCTs in which apathy was used as a secondary outcome measure, along with the considerable methodological heterogeneity, did not allow the evaluation of group effects.

CONCLUSIONS

Pharmacological interventions for apathy in aging neurocognitive disorders are complex and under-investigated. The continuation of systematic research efforts and the provision of individualized treatment for patients suffering from these disorders is vital.

Behavioral and neural correlates of pareidolic illusions in dementia with Lewy bodies

INTRODUCTION

Pareidolia, a form of visual illusions phenomenologically similar to complex visual hallucinations, is a phenomenon that is associated with visual hallucinations in dementia with Lewy bodies (DLB). This study aimed to identify commonalities and differences in behavioral and neural correlates between pareidolic illusions and visual hallucinations in DLB.

METHODS

Forty-three patients with DLB underwent the scene pareidolia test, which evokes and measures pareidolic illusions, and standardized neuropsychological and behavioral assessments. Regional cerebral blood flow (rCBF) was measured by single-photon emission computed tomography. Factor analysis was performed to assess the relationships among pareidolic illusions, cognitive functions, and behavioral symptoms. Partial least squares correlation analysis was used to investigate the relationship between these symptoms and rCBF.

RESULTS

Factor analysis yielded three behavior factors: the first factor (hallucinations/fluctuations) consisted of pareidolic illusions, visual hallucinations, and fluctuating cognition; the second factor (general cognitive function) consisted of general cognitive function and working memory; and the third factor (visual processing) consisted of visual processing and pareidolic illusions. Partial least squares correlation analysis identified two brain-behavior correlation patterns: (1) rCBF reduction in the frontal and perisylvian/periventricular regions was associated with lower general cognitive function and lower visual processing; and (2) rCBF reduction in the bilateral occipitotemporal cortex was associated with more severe hallucinations/fluctuations and lower visual processing.

CONCLUSIONS

At the behavioral level, pareidolic illusions are associated with visual hallucinations, fluctuating cognition, and visual processing in DLB. At the neural level, pareidolic illusions may arise from the synergistic effects of global neuropathological changes and occipitotemporal cortical dysfunctions.

Differential response to donepezil in MRI subtypes of mild cognitive impairment

BACKGROUND

Donepezil is an approved therapy for the treatment of Alzheimer's disease (AD). Results across clinical trials have been inconsistent, which may be explained by design-methodological issues, the pathophysiological heterogeneity of AD, and diversity of included study participants. We investigated whether response to donepezil differs in mild cognitive impaired (MCI) individuals demonstrating different magnetic resonance imaging (MRI) subtypes.

METHODS

From the Hippocampus Study double-blind, randomized clinical trial, we included 173 MCI individuals (donepezil = 83; placebo = 90) with structural MRI data, at baseline and at clinical follow-up assessments (6-12-month). Efficacy outcomes were the annualized percentage change (APC) in hippocampal, ventricular, and total grey matter volumes, as well as in the AD cortical thickness signature. Participants were classified into MRI subtypes as typical AD, limbic-predominant, hippocampal-sparing, or minimal atrophy at baseline. We primarily applied a subtyping approach based on continuous scale of two subtyping dimensions. We also used the conventional categorical subtyping approach for comparison.

RESULTS

Donepezil-treated MCI individuals showed slower atrophy rates compared to the placebo group, but only if they belonged to the minimal atrophy or hippocampal-sparing subtypes. Importantly, only the continuous subtyping approach, but not the conventional categorical approach, captured this differential response.

CONCLUSIONS

Our data suggest that individuals with MCI, with hippocampal-sparing or minimal atrophy subtype, may have improved benefit from donepezil, as compared with MCI individuals with typical or limbic-predominant patterns of atrophy. The newly proposed continuous subtyping approach may have advantages compared to the conventional categorical approach. Future research is warranted to demonstrate the potential of subtype stratification for disease prognosis and response to treatment.

TRIAL REGISTRATION

ClinicalTrial.gov NCT00403520. Submission Date: November 21, 2006.

Dementia with Lewy Bodies Drug Therapies in Clinical Trials: Systematic Review up to 2022

INTRODUCTION

Reviews of randomized clinical trials (RCTs) in dementia with Lewy bodies (DLB) are essential for informing ongoing research efforts of symptomatic therapies and potentially disease-modifying therapies (DMTs).

METHODS

We performed a systematic review of all clinical trials conducted until September 27, 2022, by examining 3 international registries: ClinicalTrials.gov, the European Union Drug Regulating Authorities Clinical Trials Database, and the International Clinical Trials Registry Platform, to identify drugs in trials in DLB.

RESULTS

We found 25 agents in 40 trials assessing symptomatic treatments and DMTs for DLB: 7 phase 3, 31 phase 2, and 2 phase 1 trials. We found an active pipeline for drug development in DLB, with most ongoing clinical trials in phase 2. We identified a recent trend towards including participants at the prodromal stages, although more than half of active clinical trials will enroll mild to moderate dementia patients. Additionally, repurposed agents are frequently tested, representing 65% of clinical trials.

CONCLUSION

Current challenges in DLB clinical trials include the need for disease-specific outcome measures and biomarkers, and improving representation of global and diverse populations.

Cholinergic nucleus 4 grey matter density is associated with apathy in Parkinson's disease

Objective: The generation and maintenance of goal-directed behavior is subserved by multiple brain regions that receive cholinergic inputs from the cholinergic nucleus 4 (Ch4). It is unknown if Ch4 degeneration contributes to apathy in Parkinson's disease (PD). Method: We analyzed data from 106 pre-surgical patients with PD who had brain MRIs and completed the Frontal Systems Behavior Scales (FrSBe). Eighty-eight patients also completed the Beck Depression Inventory-2nd Edition. Cholinergic basal forebrain grey matter densities (GMD) were measured by applying probabilistic maps to T1 MPRAGE sequences processed using voxel-based morphometry methods. We used linear and hierarchical regression modelling to examine the association between Ch4 GMD and the FrSBe Apathy subscale scores. We used similar methods to assess the specificity of this association and potential associations between Ch4 target regions and apathy. Results: Ch4 GMD (p = .021) and Ch123 GMD (p = .032) were significantly associated with Apathy subscale scores on univariate analysis. Ch4 GMD, but not Ch123 GMD, remained significantly associated with apathy when adjusting for age, sex, levodopa equivalent doses, and disease duration. Centromedial amygdala GMD, which receives cholinergic inputs from Ch4, was also associated with apathy. Ch4 GMD was not associated with depression or disinhibition, nor was it associated with executive dysfunction when adjusting for clinical and demographic variables. Conclusions: Ch4 GMD is specifically associated with apathy in PD. Ch4 degeneration results in cholinergic denervation of multiple cortical and limbic regions, which may contribute to the cognitive and emotional-affective processing deficits that underlie the behavioral symptoms of apathy.

Determinants of approved acetylcholinesterase inhibitor response outcomes in Alzheimer's disease: relevance for precision medicine in neurodegenerative diseases

Acetylcholinesterase inhibitors (ChEI) are the global standard of care for the symptomatic treatment of Alzheimer's disease (AD) and show significant positive effects in neurodegenerative diseases with cognitive and behavioral symptoms. Although experimental and large-scale clinical evidence indicates the potential long-term efficacy of ChEI, primary outcomes are generally heterogeneous across outpatient clinics and regional healthcare systems. Sub-optimal dosing or slow tapering, heterogeneous guidelines about the timing for therapy initiation (prodromal versus dementia stages), healthcare providers' ambivalence to treatment, lack of disease awareness, delayed medical consultation, prescription of ChEI in non-AD cognitive disorders, contribute to the negative outcomes. We present an evidence-based overview of determinants, spanning genetic, molecular, and large-scale networks, involved in the response to ChEI in patients with AD and other neurodegenerative diseases. A comprehensive understanding of cerebral and retinal cholinergic system dysfunctions along with ChEI response predictors in AD is crucial since disease-modifying therapies will frequently be prescribed in combination with ChEI. Therapeutic algorithms tailored to genetic, biological, clinical (endo)phenotypes, and disease stages will help leverage inter-drug synergy and attain optimal combined response outcomes, in line with the precision medicine model.

Systematic review of pharmacological interventions for people with Lewy body dementia

OBJECTIVE

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

METHOD

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

RESULTS

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

CONCLUSION

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

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

Quantitative EEG for early differential diagnosis of dementia with Lewy bodies

Introduction

Differentiating between the two most common forms of dementia, Alzheimer's dementia and dementia with Lewy bodies (DLB) remains difficult and requires the use of invasive, expensive, and resource-intensive techniques. We aimed to investigate the sensitivity and specificity of electroencephalography quantified using the statistical pattern recognition method (qEEG-SPR) for identifying dementia and DLB.

Methods

Thirty-two outpatients and 16 controls underwent clinical assessment (by two blinded neurologists), EEG recording, and a 6-month follow-up clinical assessment. EEG data were processed using a qEEG-SPR protocol to derive a Dementia Index (positive or negative) and DLB index (positive or negative) for each participant which was compared against the diagnosis given at clinical assessment. Confusion matrices were used to calculate sensitivity, specificity, and predictive values for identifying dementia and DLB specifically.

Results

Clinical assessment identified 30 cases of dementia, 2 of which were diagnosed clinically with possible DLB, 14 with probable DLB and DLB was excluded in 14 patients. qEEG-SPR confirmed the dementia diagnosis in 26 out of the 32 patients and led to 6.3% of false positives (FP) and 9.4% of false negatives (FN). qEEG-SPR was used to provide a DLB diagnosis among patients who received a positive or inconclusive result of Dementia index and led to 13.6% of FP and 13.6% of FN. Confusion matrices indicated a sensitivity of 80%, a specificity of 89%, a positive predictive value of 92%, a negative predictive value of 72%, and an accuracy of 83% to diagnose dementia. The DLB index showed a sensitivity of 60%, a specificity of 90%, a positive predictive value of 75%, a negative predictive value of 81%, and an accuracy of 75%. Neuropsychological scores did not differ significantly between DLB and non- DLB patients. Head trauma or story of stroke were identified as possible causes of FP results for DLB diagnosis.

Conclusion

qEEG-SPR is a sensitive and specific tool for diagnosing dementia and differentiating DLB from other forms of dementia in the initial state. This non-invasive, low-cost, and environmentally friendly method is a promising diagnostic tool for dementia diagnosis which could be implemented in local care settings.

Burden of Illness Among Patients with Psychosis due to Dementia with Lewy Bodies and Other Dementias

Limited research is available on the real-world experiences of patients with dementia with Lewy bodies (DLB). This study evaluated clinical events, healthcare utilization, and healthcare costs of patients with DLB vs other dementia types with psychosis (ODP). Study patients included commercial and Medicare Advantage with Part D enrollees aged ≥40 years with evidence of DLB and ODP from 6/01/2015‒5/31/2019. Compared with patients with ODP, more patients with DLB had clinical events including anticholinergic effects, neurologic effects, and cognitive decline. Patients with DLB used more healthcare resources with greater dementia-related office and outpatient visits and psychosis-related inpatient stays and office, outpatient, and emergency visits compared with their ODP patient counterparts. Patients with DLB also incurred higher healthcare costs for all-cause and dementia-related office visits and pharmacy fills, and psychosis-related total costs. Understanding the clinical and economic impact of DLB and ODP is important to improve care for patients with dementia.

A Case Report of Treatment-Resistant Agitation in Dementia with Lewy Bodies: Medical Marijuana as an Alternative to Antipsychotics

Palliative care teams are often consulted to assist in treating persistent dementia-related behavioral issues. Delta-9-tetrahydrocannabinol (THC) offers an alternative to traditional antipsychotic drugs in the long-term management of dementia with behavioral change. We present the case of an 85-year-old man with dementia with Lewy bodies with worsening aggression refractory to antipsychotic management. Multiple regimens of antipsychotics failed both in the outpatient and inpatient settings. After exhausting other options and in the setting of worsening agitation, a tincture of THC was prescribed. After starting THC tincture, the patient's behavior rapidly improved, and he was discharged home to the care of his spouse. The challenges of prescribing and obtaining THC are discussed.

The hippocampal sparing subtype of Alzheimer's disease assessed in neuropathology and in vivo tau positron emission tomography: a systematic review

Neuropathology and neuroimaging studies have identified several subtypes of Alzheimer's disease (AD): hippocampal sparing AD, typical AD, and limbic predominant AD. An unresolved question is whether hippocampal sparing AD cases can present with neurofibrillary tangles (NFT) in association cortices while completely sparing the hippocampus. To address that question, we conducted a systematic review and performed original analyses on tau positron emission tomography (PET) data. We searched EMBASE, PubMed, and Web of Science databases until October 2022. We also implemented several methods for AD subtyping on tau PET to identify hippocampal sparing AD cases. Our findings show that seven out of the eight reviewed neuropathologic studies included cases at Braak stages IV or higher and therefore, could not identify hippocampal sparing cases with NFT completely sparing the hippocampus. In contrast, tau PET did identify AD participants with tracer retention in the association cortex while completely sparing the hippocampus. We conclude that tau PET can identify hippocampal sparing AD cases with NFT completely sparing the hippocampus. Based on the accumulating data, we suggest two possible pathways of tau spread: (1) a canonical pathway with early involvement of transentorhinal cortex and subsequent involvement of limbic regions and association cortices, and (2) a less common pathway that affects association cortices with limbic involvement observed at end stages of the disease or not at all.

Amitriptyline Improves Cognitive and Neuronal Function in a Rat Model that Mimics Dementia with Lewy Bodies

Dementia with Lewy bodies (DLB), a highly prevalent neurodegenerative disorder, causes motor and cognitive deficits. The main pathophysiologies of DLB are glutamate excitotoxicity and accumulation of Lewy bodies comprising α-synuclein (α-syn) and β-amyloid (Aβ). Amitriptyline (AMI) promotes expression of glutamate transporter-1 and glutamate reuptake. In this study, we measured the effects of AMI on behavioral and neuronal function in a DLB rat model. We used rivastigmine (RIVA) as a positive control. To establish the DLB rat model, male Wistar rats were stereotaxically injected with recombinant adenoassociated viral vector with the SNCA gene (10μg/10μL) and Aβ (5μg/2.5μL) into the left ventricle and prefrontal cortex, respectively. AMI (10mg/kg/day, i.p.), RIVA (2mg/kg/day, i.p.), or saline was injected intraperitoneally after surgery. From the 29^th day, behavioral tests were performed to evaluate the motor and cognitive functions of the rats. Immunohistochemical staining was used to assess neuronal changes. We measured the α-syn level, number of newborn cells, and neuronal density in the hippocampus and in the nigrostriatal dopaminergic system. The DLB group exhibited deficit in object recognition. Both the AMI and RIVA treatments reversed these deficits. Histologically, the DLB rats exhibited cell loss in the substantia nigra pars compacta and in the hippocampal CA1 area. AMI reduced this cell loss, but RIVA did not. In addition, the DLB rats exhibited a lower number of newborn cells and higher α-syn levels in the dentate gyrus (DG). AMI did not affect α-syn accumulation but recovered neurogenesis in the DG of the rats, whereas RIVA reversed the α-syn accumulation but did not affect neurogenesis in the rats. We suggest that AMI may have potential for use in the treatment of DLB.

Current Therapies and Drug Development Pipeline in Lewy Body Dementia: An Update

The term Lewy body dementia refers to either of two related diagnoses: dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD). Clinical management of Lewy body dementia is challenging. The current treatment options focus on relieving symptoms; no disease-modifying therapies are available. There are currently no US Food and Drug Administration (FDA) approved drugs for the treatment of DLB, and there are only a few for PDD. Cholinesterase inhibitors are shown to be beneficial in improving cognitive symptoms in Lewy body dementia. Rivastigmine was approved by the FDA to treat PDD. Donepezil was approved in Japan as a treatment for DLB. Levodopa may provide modest benefit in treating motor symptoms and zonisamide in adjunct to low-dose levodopa helps with parkinsonism. Treatment of autonomic symptoms are based on symptomatic treatment with off-label agents. Our main objective in this article is to present an overview of the current pharmacological options available to treat the clinical features of DLB and PDD. When evaluating the existing management options for Lewy body dementia, it is difficult to fully separate PDD from DLB. However, we have attempted to identify whether the cited studies include patients with PDD and/or DLB. Moreover, we have provided an overview of the current drug pipeline in Lewy body dementia. All currently active trials are in phase I or II and most are focused on disease modification rather than symptomatic treatment. Phase II trial results for neflamapimod show promising results. Due to heterogeneity of symptoms and underlying pathophysiology, there is a need for new biomarker strategies and improved definitions of outcome measures for Lewy body dementia drug trials.

Clinical outcome measures in dementia with Lewy bodies trials: critique and recommendations

The selection of appropriate outcome measures is fundamental to the design of any successful clinical trial. Although dementia with Lewy bodies (DLB) is one of the most common neurodegenerative conditions, assessment of therapeutic benefit in clinical trials often relies on tools developed for other conditions, such as Alzheimer's or Parkinson's disease. These may not be sufficiently valid or sensitive to treatment changes in DLB, decreasing their utility. In this review, we discuss the limitations and strengths of selected available tools used to measure DLB-associated outcomes in clinical trials and highlight the potential roles for more specific objective measures. We emphasize that the existing outcome measures require validation in the DLB population and that DLB-specific outcomes need to be developed. Finally, we highlight how the selection of outcome measures may vary between symptomatic and disease-modifying therapy trials.

Acetylcholinesterase inhibitors to enhance recovery from traumatic brain injury: a comprehensive review and case series

OBJECTIVE

Acetylcholinesterase inhibitors (AChEIs) are used off-label, in both adult and pediatric patients, to help further neuro-recovery after traumatic brain injury (TBI). Evidence is limited and piecemeal. This review describes how TBI affects the cholinergic system and consolidates evidence supporting or refuting the use of AChEIs following TBI.

METHODS

NCBI MEDLINE search included all articles published through March 2021 on AChEI use in acute and post-acute adult TBI rehabilitation (treatment began <90 days or ≥90 days since injury, respectively), and in pediatric TBI rehabilitation. Further, we checked ClinicalTrials.gov for ongoing trials using AChEIs for TBI rehabilitation in the United States.

RESULTS

27 original articles from NCBI Medline, published through March 2021, were included. The use of AChEIs following TBI in acute and post-acute rehabilitation settings, in both adult and pediatric patients, along with medication side effects, is discussed.

CONCLUSIONS

Most studies showed benefits with only moderate effect sizes because of small sample sizes. Reported side effects are minimal and stop soon after AChEIs is discontinued. Conclusions are limited by paucity of research; but fortunately, a large randomized controlled trial is ongoing, and more are needed to truly determine the efficacy of AChEIs in helping with recovery from TBI.

Dementia-related psychosis and the potential role for pimavanserin

Dementia-related psychosis (DRP) is prevalent across dementias and typically manifests as delusions and/or hallucinations. The mechanisms underlying psychosis in dementia are unknown; however, neurobiological and pharmacological evidence has implicated multiple signaling pathways and brain regions. Despite differences in dementia pathology, the neurobiology underlying psychosis appears to involve dysregulation of a cortical and limbic pathway involving serotonergic, gamma-aminobutyric acid ergic, glutamatergic, and dopaminergic signaling. Thus, an imbalance in cortical and mesolimbic excitatory tone may drive symptoms of psychosis. Delusions and hallucinations may result from (1) hyperactivation of pyramidal neurons within the visual cortex, causing visual hallucinations and (2) hyperactivation of the mesolimbic pathway, causing both delusions and hallucinations. Modulation of the 5-HT2A receptor may mitigate hyperactivity at both psychosis-associated pathways. Pimavanserin, an atypical antipsychotic, is a selective serotonin inverse agonist/antagonist at 5-HT2A receptors. Pimavanserin may prove beneficial in treating the hallucinations and delusions of DRP without worsening cognitive or motor function.

Pharmacological Management of Apathy in Dementia

Apathy is a highly prevalent symptom of dementia. Despite its association with faster cognitive and functional decline, decreased quality of life and increased mortality, no therapies are currently approved to treat apathy. The objective of this review was to summarize the drugs that have been studied for apathy treatment in patients with dementia (specifically Alzheimer's disease [AD], Huntington's disease [HD] and Parkinson's disease [PD] dementia; dementia with Lewy bodies [DLB]; vascular dementia [VaD]; and frontotemporal dementia [FTD]) based on their putative mechanisms of action. A search for relevant studies was performed using ClinicalTrials.gov and PubMed. Eligible studies were randomized controlled trials that were available in English and included at least one drug intervention and an apathy measure scale. A total of 52 studies that included patients with AD (n = 33 studies), PD (n = 5), HD (n = 1), DLB (n = 1), FTD (n = 3), VaD (n = 1), VaD and AD (n = 4), VaD and mixed dementia (n = 1), and AD, VaD and mixed dementia (n = 3) were eligible for inclusion. These studies showed that methylphenidate, olanzapine, cholinesterase inhibitors, choline alphoscerate, citalopram, memantine, and mibampator are the only beneficial drugs in AD-related apathy. For PD-related apathy, only methylphenidate, rotigotine and rivastigmine showed benefits. Regarding FTD- and DLB-related apathy, initial studies with agomelatine and rivastigmine showed benefits, respectively. As for HD- and only-VaD-related apathy, no drugs demonstrated benefits. With regards to mixed populations, memantine, galantamine and gingko biloba showed effects on apathy in the AD plus VaD populations and nimodipine in the VaD plus mixed dementia populations. Of the drugs with positive results, some are already prescribed to patients with dementia to target other symptoms, some have characteristics-such as medical contraindications (e.g., cardiovascular) and adverse effects (e.g., gastrointestinal disturbances)-that limit their clinical use and some require further study. Future studies should investigate apathy as a primary outcome, making use of appropriate sample sizes and study durations to ensure durability of results. There should also be a consensus on using scales with high test/retest and interrater reliabilities to limit the inconsistencies between clinical trials. In conclusion, there are currently no US FDA-approved drugs that target apathy in dementia, so there is an ongoing need for the development of such drugs.

A New Perspective on the Treatment of Alzheimer's Disease and Sleep Deprivation-Related Consequences: Can Curcumin Help?

Sleep disturbances, as well as sleep-wake rhythm disorders, are characteristic symptoms of Alzheimer's disease (AD) that may head the other clinical signs of this neurodegenerative disease. Age-related structural and physiological changes in the brain lead to changes in sleep patterns. Conditions such as AD affect the cerebral cortex, basal forebrain, locus coeruleus, and the hypothalamus, thus changing the sleep-wake cycle. Sleep disorders likewise adversely affect the course of the disease. Since the sleep quality is important for the proper functioning of the memory, impaired sleep is associated with problems in the related areas of the brain that play a key role in learning and memory functions. In addition to synthetic drugs, utilization of medicinal plants has become popular in the treatment of neurological diseases. Curcuminoids, which are in a diarylheptanoid structure, are the main components of turmeric. Amongst them, curcumin has multiple applications in treatment regimens of various diseases such as cardiovascular diseases, obesity, cancer, inflammatory diseases, and aging. Besides, curcumin has been reported to be effective in different types of neurodegenerative diseases. Scientific studies exclusively showed that curcumin leads significant improvements in the pathological process of AD. Yet, its low solubility hence low bioavailability is the main therapeutic limitation of curcumin. Although previous studies have focused different types of advanced nanoformulations of curcumin, new approaches are needed to solve the solubility problem. This review summarizes the available scientific data, as reported by the most recent studies describing the utilization of curcumin in the treatment of AD and sleep deprivation-related consequences.

Outcome Measures for Dementia With Lewy Body Clinical Trials: A Review

BACKGROUND

Dementia with Lewy bodies (DLB) is one of the most common degenerative dementias. Clinical trials for individuals with DLB are increasing. We aimed to identify commonly used outcome measures for trials in DLB.

METHODS

A pragmatic literature search of PubMed and clinicaltrials.gov identified interventional studies including populations with DLB. Studies were included if they enrolled participants with DLB and met the National Institutes of Health criteria for a clinical trial. Data were collected using standardized forms. Outcome measures were categorized according to core and supportive features of DLB.

RESULTS

After de-duplication, 58 trials were identified. The most common cognitive outcome measures were the Mini Mental State Examination (n=24) and Cognitive Drug Research computerized Assessment System (n=5). The Clinician's Assessment of Fluctuations was the most commonly used measure for fluctuations (n=4). Over half of studies used the Neuropsychiatric Inventory to assess behavioral symptoms (n=31). The Unified Parkinson's Disease Rating Scale was frequently used for motor assessment (n=23).

CONCLUSIONS AND RELEVANCE

Clinical trial outcomes used in DLB are rarely validated in this population and some lack face validity. There is a need to validate existing scales in DLB and develop DLB-specific outcome measures.

Psychosis

PURPOSE OF REVIEW

Psychosis can manifest in primary psychotic disorders, neurologic diseases, and medical conditions. This article reviews the definition of psychotic symptoms and the evaluation and management of psychosis in primary psychiatric and neurologic disorders frequently seen in neurologic practice.

RECENT FINDINGS

Emerging evidence supports significant connections between psychosis and structural and functional brain changes in both primary psychotic and neurologic disorders. In addition to antidopaminergic activity, the mechanism of new-generation antipsychotics shifts to act on serotonin receptors, which potentially contributes to their benefits in the treatment of negative symptoms of psychosis and a lesser frequency of extrapyramidal side effects compared with typical antipsychotics. This is also helpful in the treatment of psychosis in patients who have neurodegenerative diseases and are vulnerable to developing extrapyramidal side effects from typical antipsychotics.

SUMMARY

Even with significant overlap, management of psychosis in primary psychotic disorders differs from the approach of psychosis in neurologic diseases. This article helps clinicians learn how to practically evaluate psychosis from both psychiatric and neurologic perspectives.

Progression of Clinical Features in Lewy Body Dementia Can Be Detected Over 6 Months

OBJECTIVE

This study aimed to quantify the trajectory and magnitude of change of the key clinical features and corresponding symptom domains of dementia with Lewy bodies (DLB) and Parkinson disease dementia (PDD), including global cognition, parkinsonism, recurrent visual hallucinations, cognitive fluctuations, and sleep disturbance.

METHODS

One hundred sixteen patients with Lewy body dementia (DLB = 72, PDD = 44) underwent assessment at baseline and 3 and 6 months as part of a prospective multicenter randomized controlled trial. Linear mixed models were constructed for core outcome measures using the Mini-Mental State Examination (MMSE), motor section of the Unified Parkinson's Disease Rating Scale (UPDRS-III), Dementia Cognitive Fluctuations Scale (DCFS), and Neuropsychiatric Inventory (NPI).

RESULTS

Within the time frame of our study (6 months), we were able to identify a significant cognitive decline of 1.3 points on the MMSE (p = 0.002) and significant worsening of motor parkinsonism with an increase in UPDRS-III score of 3.2 points (p = 0.018). Fluctuation severity also increased using the DCFS with a 6-month change in score of 1.3 points (p = 0.001). Uniquely, a signal for increased severity of sleep symptoms of 1.2 points (NPI-sleep) was also detectable (p = 0.04). Significant changes in neuropsychiatric symptoms were not detected. There was no difference in rates of change of scores between DLB and PDD.

DISCUSSION

Clinically significant rates of change in core clinical features can be detected and quantified in Lewy body dementia over a relatively short period (6 months) using common clinical instruments and thus may be useful as clinical endpoints for therapeutic trials of disease-modifying and symptomatic agents.

Medications causing potential cognitive impairment are common in nursing home dementia units – A cross-sectional study

Background

With advancing age the brain becomes more sensitive to centrally acting drugs thus increasing the risk of cognitive side-effects. The Swedish National Board of Health and Welfare developed indicators to measure and follow quality in older people's drug therapy, one being “Potentially Inappropriate Medications risking Cognitive impairment (PIMcogn)”. Associations between anticholinergics and cognitive impairment are described, especially in persons with Alzheimer's disease or Lewy Body Dementia/Parkinson's disease dementia, due to degenerated cholinergic pathways.

Objectives

To examine the prevalence of PIMcogn and if it differed between nursing home residents with and without a dementia diagnosis and between residents with different dementia aetiologias.

Methods

Descriptive cross-sectional study, based on residents ≥65 years in nursing home dementia units in Malmö, Sweden, in 2012–2013 (N = 574).

Results

The study population consisted of 76% women, the mean age was 86 years and a dementia diagnosis was registered in 92%. A total of 74% were prescribed at least one PIMcogn. Benzodiazepines were prevalent in 59%, opioids in 27%, antipsychotics in 20% and anticholinergics in 13%. Opioids used regularly and antiepileptics were more common in residents without a dementia diagnosis. The lowest proportion of anticholinergics was seen in the oldest age group, 11.0%. There was no difference seen in anticholinergics between dementia types with considerable cholinergic deficit and other dementia diagnoses.

Conclusions

Treatment with at least one PIMcogn was common. Usage of benzodiazepines and antipsychotics was, despite the knowledge of alarming side-effects, high.

An awareness of the inappropriateness in prescribing anticholinergics to the oldest old seems to be apparent, but not to persons with cholinergic deficit.

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Benzodiazepine use was alarmingly high, despite the knowledge of increased risk of sedation, cognitive impairment, delirium and fall in older people.

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Antipsychotics were common in residents with dementia. This is worrying since alarming side-effects are seen in these persons and treatment effects of antipsychotics are modest in BPSD.

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An awareness of the inappropriateness in prescribing anticholinergics to the oldest old seem to be apparent, but not to persons with cholinergic deficit due to Alzheimer's disease or LBD/PDD.

Real-world Evaluation of Tolerability, Safety and Efficacy of Rivastigmine Oral Solution in Patients with Mild to Moderate Alzheimer's Disease Dementia

OBJECTIVE

The purpose of this study is to investigate the safety, tolerability and efficacy of titrating dose of rivastigmine oral solution in patients with mild to moderate Alzheimer's disease (AD) in Taiwan.

METHODS

We recruited 108 mild to moderate AD patients with RivastⓇ (rivastigmine oral solution 2 mg/ml) treatment for 52 weeks. We recorded the demographic characteristics, initial cognition by mini-mental state examination (MMSE), initial global status by clinical dementia rating (CDR) with CDR-Sum of Boxes (CDR-SB), initial dose, and titrating dose at each visit. We investigated the adherence, proportion of possible side effects, optimal dose, and time to optimal dose. We demonstrated the proportion of cognitive decline and its possible risk factors.

RESULTS

During the course, 9 patients discontinued the rivastigmine oral solution due to poor compliance or preference. Twelve out of 99 patients (12.1%) reported possible side effects. Among 87 patients, the mean age was 77.2 ± 9.0 years ago with female predominant (65.2%). The optimal dose was 3.6 ± 1.4 ml in average and 4 ml (n = 31, 35.6%) in mode. The duration to optimal dose was 12.5 ± 10.2 weeks and 24 weeks (n = 35, 40.2%) in mode. It presented 25% with cognitive decline in MMSE, 27% with global function decline in CDR and 63% with global function decline in CDR-SB.

CONCLUSION

We demonstrated the clinical experience of rivastigmine oral solution in mild to moderate AD patients. It suggested rivastigmine oral solution 4ml is the optimal dose with 24 weeks to the optimal dose for at least one third of patients.

Treatment Efficacy and Acceptabilityof Pharmacotherapies for Dementia with Lewy Bodies: A Systematic Review and Network Meta-Analysis

INTRODUCTION

We investigated the efficacy and acceptability of pharmacotherapy for dementia with Lewy bodies (DLB) while simultaneously considering the neuropsychiatric symptoms (NPS), cognitive function, motor symptoms, and acceptability.

METHODS

Electronic databases were searched from inception through June 5, 2019, for randomized controlled trials (RCTs) and open-label trials (OLTs) in patients with DLB. We performed a pairwise conventional meta-analysis (PWMA) and network meta-analysis (NMA) within a frequentist framework. The main outcomes were mean change scores in NPS, general cognition, motor symptoms and acceptability. The effect sizes and odds ratios with 95% confidence intervals (CIs) were calculated. This study was registered with PROSPERO (CRD42018096996).

RESULTS

In total, we included 29 studies (9 RCTs and 20 OLTs). In the NMA with 9 RCTs, both high- (mean difference [MD] 2.00, 95% CIs, 0.69 to 3.31) and low-dose (1.86, 0.58 to 3.15) donepezil were associated with a greater cognitive improvement than placebo. High-dose zonisamide was associated with greater motor symptom improvement ( -4.10, -7.03 to -1.17]). No medications reached statistical significance regarding improving neuropsychiatric symptoms or developing intolerable adverse effects as compared to placebo. In the second NMA, with 29 studies as an exploratory analysis, aripiprazole and yokukansan may be effective for neuropsychiatric symptoms, while levodopa may be associated with cognitive impairment.

CONCLUSIONS

We report the most comprehensive evidence for the selection of pharmacotherapy for treating different clusters of DLB-related symptoms. Due to the limited availability of RCTs on DLB, more well-conducted RCTs are needed for MMA to warrant clinical efficacy in the future.

An international, randomized, placebo-controlled, phase 2b clinical trial of intepirdine for dementia with Lewy bodies (HEADWAY-DLB)

INTRODUCTION

A phase 2b clinical trial, HEADWAY-DLB, was performed to assess treatment with intepirdine, a serotonin receptor antagonist, in patients with dementia with Lewy bodies (DLB).

METHODS

HEADWAY-DLB was a multinational, double-blind, randomized, placebo-controlled study. Two hundred sixty-nine DLB patients were randomized to receive placebo, 70 mg/day intepirdine, or 35 mg/day intepirdine over 24 weeks. The primary endpoint was change from baseline to week 24 on the Unified Parkinson's Disease Rating Scale-Part III (UPDRS-III).

RESULTS

Both intepirdine groups did not demonstrate significant benefits over placebo at 24 weeks on the UPDRS-III (35 mg/day: P = .1580, 70 mg/day: P = .6069). All other endpoints were not significant. Intepirdine was well tolerated, with a slightly higher incidence of gastrointestinal adverse events observed in the intepirdine groups versus placebo.

DISCUSSION

Intepirdine treatment did not lead to improvements over placebo in patients with DLB. As one of the largest DLB studies to date, HEADWAY-DLB demonstrates that international trials for DLB are feasible within a reasonable timeframe.

Agitation and Dementia: Prevention and Treatment Strategies in Acute and Chronic Conditions

Agitation is a behavioral syndrome characterized by increased, often undirected, motor activity, restlessness, aggressiveness, and emotional distress. According to several observations, agitation prevalence ranges from 30 to 50% in Alzheimer's disease, 30% in dementia with Lewy bodies, 40% in frontotemporal dementia, and 40% in vascular dementia (VaD). With an overall prevalence of about 30%, agitation is the third most common neuropsychiatric symptoms (NPS) in dementia, after apathy and depression, and it is even more frequent (80%) in residents of nursing homes. The pathophysiological mechanism underlying agitation is represented by a frontal lobe dysfunction, mostly involving the anterior cingulate cortex (ACC) and the orbitofrontal cortex (OFC), respectively, meaningful in selecting the salient stimuli and subsequent decision-making and behavioral reactions. Furthermore, increased sensitivity to noradrenergic signaling has been observed, possibly due to a frontal lobe up-regulation of adrenergic receptors, as a reaction to the depletion of noradrenergic neurons within the locus coeruleus (LC). Indeed, LC neurons mainly project toward the OFC and ACC. These observations may explain the abnormal reactivity to weak stimuli and the global arousal found in many patients who have dementia. Furthermore, agitation can be precipitated by several factors, e.g., the sunset or low lighted environments as in the sundown syndrome, hospitalization, the admission to nursing residencies, or changes in pharmacological regimens. In recent days, the global pandemic has increased agitation incidence among dementia patients and generated higher distress levels in patients and caregivers. Hence, given the increasing presence of this condition and its related burden on society and the health system, the present point of view aims at providing an extensive guide to facilitate the identification, prevention, and management of acute and chronic agitation in dementia patients.

The effects of anticholinergic medications on cognition in children: a systematic review and meta-analysis

Cognitive side effects of anticholinergic medications in older adults are well documented. Whether these poor cognitive outcomes are observed in children has not been systematically investigated. We aimed to conduct a systematic review and meta-analysis on the associations between anticholinergic medication use and cognitive performance in children. Systematic review was conducted using Medline, PsychInfo, and Embase, identifying studies testing cognitive performance relative to the presence versus absence of anticholinergic medication(s) in children. We assessed effects overall, as well as relative to drug class, potency (low and high), cognitive domain, and duration of administration. The systematic search identified 46 articles suitable for meta-analysis. For the most part, random effects meta-analyses did not identify statistically significant associations between anticholinergic exposure and cognitive performance in children; the one exception was a small effect of anticholinergic anti-depressants being associated with better cognitive function (Hedges' g = 0.24, 95% CI 0.06-0.42, p = 0.01). Anticholinergic medications do not appear to be associated with poor cognitive outcomes in children, as they do in older adults. The discrepancy in findings with older adults may be due to shorter durations of exposure in children, differences in study design (predominantly experimental studies in children rather than predominantly epidemiological in older adults), biological ageing (e.g. blood brain barrier integrity), along with less residual confounding due to minimal polypharmacy and comorbidity in children.

Relevance of 5-HT2A Receptor Modulation of Pyramidal Cell Excitability for Dementia-Related Psychosis: Implications for Pharmacotherapy

Psychosis occurs across a wide variety of dementias with differing etiologies, including Alzheimer's dementia, Parkinson's dementia, Lewy body dementia, frontotemporal dementia, and vascular dementia. Pimavanserin, a selective serotonin 5-HT_2A receptor (5-HT_2AR) inverse agonist, has shown promising results in clinical trials by reducing the frequency and/or severity of hallucinations and delusions and the risk of relapse of these symptoms in patients with dementia-related psychosis. A literature review was conducted to identify mechanisms that explain the role of 5-HT_2ARs in both the etiology and treatment of dementia-related psychosis. This review revealed that most pathological changes commonly associated with neurodegenerative diseases cause one or more of the following events to occur: reduced synaptic contact of gamma aminobutyric acid (GABA)-ergic interneurons with glutamatergic pyramidal cells, reduced cortical innervation from subcortical structures, and altered 5-HT_2AR expression levels. Each of these events promotes increased pyramidal cell hyperexcitability and disruption of excitatory/inhibitory balance, facilitating emergence of psychotic behaviors. The brain regions affected by these pathological changes largely coincide with areas expressing high levels of 5-HT_2ARs. At the cellular level, 5-HT_2ARs are most highly expressed on cortical glutamatergic pyramidal cells, where they regulate pyramidal cell excitability. The common effects of different neurodegenerative diseases on pyramidal cell excitability together with the close anatomical and functional connection of 5-HT_2ARs to pyramidal cell excitability may explain why suppressing 5-HT_2AR activity could be an effective strategy to treat dementia-related psychosis.

Treatment Options for Dementia with Lewy Bodies: A Network Meta-Analysis of Randomised Control Trials

INTRODUCTION

Dementia with Lewy bodies (DLB) is the third most common type of dementia after Alzheimer's disease (AD) and vascular dementia. Treatment is targeted at specific disease manifestations/symptoms. While donepezil is approved for the treatment of DLB in Japan, to date no other treatment has been approved for this indication anywhere in the world. Notwithstanding, many of the medications that are approved for AD are widely used in the treatment of DLB with varying degrees of success. Consequently, clinical evidence is limited, and there is a need to understand the comparative efficacy and safety of currently used therapies for DLB. The aim of this study was to conduct a network meta-analysis (NMA) to evaluate the outcomes of the available treatment options based on currently used trial endpoints.

METHODS

Using data from a previously published systematic review, we conducted an NMA to investigate the efficacy and safety of treatments in patients with DLB. Networks were based on change from baseline of efficacy endpoints (Mini-Mental State Examination; Neuropsychiatric Inventory; Unified Parkinson's Disease Rating Scale) and rate of safety events (overall adverse events [AEs]; discontinuations; discontinuations due to AEs; psychiatric events).

RESULTS

Focused around a common treatment option of placebo, the NMA comprised studies on donepezil, rivastigmine, memantine and quetiapine. Donepezil 3 mg, 5 mg and 10 mg doses were compared against each other and placebo. Overall, donepezil consistently performed better than the alternative treatments when compared to placebo for all efficacy and safety endpoints. However, the small sample size and/or heterogeneity of the studies led to uncertainty, resulting in no statistically significant differences favouring any treatment above another or placebo.

CONCLUSION

Despite the lack of statistical significance, when assessing the efficacy and safety outcomes for each drug in the evidence network, donepezil appeared to have a more favourable overall benefit/risk profile for patients with DLB. Further comparative trials are required to improve understanding of the true difference between existing and potential future treatment options.

Nucleus Basalis of Meynert Stimulation for Lewy Body Dementia: A Phase I Randomized Clinical Trial

OBJECTIVES

Nucleus basalis of Meynert deep brain stimulation (NBM-DBS) has been proposed for patients with dementia. Here, we aim to assess the safety and effects of NBM-DBS in patients with Lewy body dementia (LBD), in a randomized, double-blind, crossover clinical trial.

METHODS

Six patients with mild to moderate LBD (mean [SD] age, 62.2 [7.8] years) were included, operated on for bilateral NBM-DBS, and assigned to receive either active or sham NBM-DBS followed by the opposite condition for 3 months. The primary outcome was the difference in the total free recalls of the Free and Cued Selective Reminding Test (FCSRT) between active and sham NBM-DBS. Secondary outcomes were assessments of the safety and effects of NBM-DBS on cognition, motor disability, sleep, and PET imaging.

RESULTS

There was no significant difference in the FCSRT score with active vs sham NBM-DBS. The surgical procedures were well tolerated in all patients, but we observed significant decreases in Stroop and Benton scores after electrode implantation. We observed no significant difference in other scales between active and sham NBM-DBS. With active NBM-DBS relative to baseline, phonemic fluency and motor disability significantly decreased. Lastly, the superior lingual gyrus metabolic activity significantly increased with active NBM-DBS.

CONCLUSIONS

NBM-DBS does not appear to be totally safe for patients with LBD with no evidence of cognitive benefit.

CLINICALTRIALSGOV IDENTIFIER

NCT01340001.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that, for patients with LBD operated on for bilateral NBM-DBS, active NBM-DBS stimulation compared to sham stimulation did not significantly change selective recall scores.

Delirium

Delirium, a syndrome characterized by an acute change in attention, awareness and cognition, is caused by a medical condition that cannot be better explained by a pre-existing neurocognitive disorder. Multiple predisposing factors (for example, pre-existing cognitive impairment) and precipitating factors (for example, urinary tract infection) for delirium have been described, with most patients having both types. Because multiple factors are implicated in the aetiology of delirium, there are likely several neurobiological processes that contribute to delirium pathogenesis, including neuroinflammation, brain vascular dysfunction, altered brain metabolism, neurotransmitter imbalance and impaired neuronal network connectivity. The Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) is the most commonly used diagnostic system upon which a reference standard diagnosis is made, although many other delirium screening tools have been developed given the impracticality of using the DSM-5 in many settings. Pharmacological treatments for delirium (such as antipsychotic drugs) are not effective, reflecting substantial gaps in our understanding of its pathophysiology. Currently, the best management strategies are multidomain interventions that focus on treating precipitating conditions, medication review, managing distress, mitigating complications and maintaining engagement to environmental issues. The effective implementation of delirium detection, treatment and prevention strategies remains a major challenge for health-care organizations globally.

FLAME: A computerized neuropsychological composite for trials in early dementia

Introduction

Sensitive neuropsychological tests are needed to improve power for clinical trials in early Alzheimer's disease (AD).

Methods

To develop a neuropsychological composite (FLAME – Factors of Longitudinal Attention, Memory and Executive Function), we assessed, 10,714 participants over the age of 50 from PROTECT with validated computerized assessments for 2 years. A factorial analysis was completed to identify the key cognitive factors in all participants, and further analyses examined sensitivity to change in people with stage 2/3 early Alzheimer's disease (AD) according to the US Food and Drug Administration (FDA) framework.

Results

The FLAME composite score (speed of attention, accuracy of attention, memory, and executive function) distinguished between normal cognition and stage 2/3 early AD at baseline, and was sensitive to cognitive and global/functional decline over 2 years, with the potential to improve power for clinical trials.

Discussion

FLAME is sensitive to change, providing a straightforward approach to reduce sample size for RCTs in early AD.

Conclusion

FLAME is a useful computerized neuropsychology composite with utility for clinical trials focusing on cognition.

Cholinergic Modulation of Glial Function During Aging and Chronic Neuroinflammation

Aging is a complex biological process that increases the risk of age-related cognitive degenerative diseases such as dementia, including Alzheimer’s disease (AD), Lewy Body Dementia (LBD), and mild cognitive impairment (MCI). Even non-pathological aging of the brain can involve chronic oxidative and inflammatory stress, which disrupts the communication and balance between the brain and the immune system. There has been an increasingly strong connection found between chronic neuroinflammation and impaired memory, especially in AD. While microglia and astrocytes, the resident immune cells of the central nervous system (CNS), exerting beneficial effects during the acute inflammatory phase, during chronic neuroinflammation they can become more detrimental. Central cholinergic circuits are involved in maintaining normal cognitive function and regulating signaling within the entire cerebral cortex. While neuronal-glial cholinergic signaling is anti-inflammatory and anti-oxidative, central cholinergic neuronal degeneration is implicated in impaired learning, memory sleep regulation, and attention. Although there is evidence of cholinergic involvement in memory, fewer studies have linked the cholinergic anti-inflammatory and anti-oxidant pathways to memory processes during development, normal aging, and disease states. This review will summarize the current knowledge of cholinergic effects on microglia and astroglia, and their role in both anti-inflammatory and anti-oxidant mechanisms, concerning normal aging and chronic neuroinflammation. We provided details on how stimulation of α7 nicotinic acetylcholine (α7nACh) receptors can be neuroprotective by increasing amyloid-β phagocytosis, decreasing inflammation and reducing oxidative stress by promoting the nuclear factor erythroid 2-related factor 2 (Nrf2) pathways and decreasing the release of pro-inflammatory cytokines. There is also evidence for astroglial α7nACh receptor stimulation mediating anti-inflammatory and antioxidant effects by inhibiting the nuclear factor-κB (NF-κB) pathway and activating the Nrf2 pathway respectively. We conclude that targeting cholinergic glial interactions between neurons and glial cells via α7nACh receptors could regulate neuroinflammation and oxidative stress, relevant to the treatment of several neurodegenerative diseases.

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

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Effect of biological treatments on psychotic symptoms in lewy body disease: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVES

Parkinson disease and dementia with Lewy bodies (collectively termed Lewy body disease) are common neurodegenerative conditions of later life and are frequently associated with distressing psychotic symptoms. The best approach to manage these symptoms is yet to be established and current treatments carry the risk of serious adverse effects.

METHODS

We performed a systematic review and meta-analysis of 19 randomized controlled trials investigating the efficacy of biological treatments for psychotic symptoms in Lewy body disease.

RESULTS

The summary effect estimate did not show a statistically significant benefit of biological treatments for psychotic symptoms in Lewy body disease (SMD -0.48, 95%CI -1.01 to 0.04). This was irrespective of the choice of intervention (SMD -0.53, 95%CI -1.20 to 0.14 for antipsychotic trials) or disease status (SMD -0.59, 95%CI -1.24 to 0.05 for trials of Parkinson disease). There was a significant effect for biological treatments compared with placebo in trials that lasted at least 6 weeks (SMD -0.25, 95%CI -0.43 to -0.08) and those with sample sizes greater than 100 participants (SMD of -0.28 95%CI -0.45 to -0.11).

CONCLUSIONS

In this systematic review and meta-analysis, treatment of psychotic symptoms by biological means did not improve symptoms compared with placebo. Small sample sizes, modest treatment durations, and other methodological differences across the trials do make it difficult to draw firm conclusions. Longer, adequately powered trials utilizing established and novel treatments are needed to provide more definitive evidence to guide clinicians in the best choice of agent to treat these distressing and often persistent symptoms.

Neuroanatomical Abnormalities in Older Depressed Adults With Apathy: A Systematic Review

OBJECTIVE

Apathy is a common phenomenon in late-life depression and is associated with poor outcomes. Apathy is often unrecognized in older depressed adults, and efficacious treatment options are lacking. This review provides a systematic review of the neuroanatomical abnormalities associated with apathy in late-life depression. In addition, the review summarizes the neuroimaging findings from studies of neurodegenerative and focal brain injury conditions that frequently present with apathy. The goal is to elucidate cerebral network abnormalities that give rise to apathy in older adults with mood disturbances and to inform future treatment targets.

METHOD

Systematic literature review.

RESULTS

The few studies that have directly examined the neuroanatomical abnormalities of apathy in late-life depression suggest disturbances in the anterior cingulate cortex, insula, orbital and dorsal prefrontal cortex, striatum, and limbic structures (ie, amygdala, thalamus, and hippocampus). Studies examining the neuroanatomical correlates of apathy in other aging populations are consistent with the pattern observed in late-life depression.

CONCLUSIONS

Apathy in late-life depression appears to be accompanied by neuroanatomical abnormalities in the salience and reward networks. These network findings are consistent with that observed in individuals presenting with apathy in other aging-related conditions. These findings may inform future treatments that target apathy.