The spectrum of behavioral changes in Alzheimer's disease

Association of brain amyloidosis with the incidence and frequency of neuropsychiatric symptoms in ADNI: a multisite observational cohort study

OBJECTIVE

To investigate the relationship between amyloid burden and frequency of existing and incidence of new neuropsychiatric symptoms (NPS) in elderly with and without cognitive decline.

METHODS

275 cognitively normal controls (NC), 100 subjective memory complaint (SMC), 559 mild cognitive impairment (MCI) and 143 Alzheimer's disease dementia subjects from the Alzheimer's Disease Neuroimaging Initiative received (¹⁸F)-florbetapir positron emission tomography (PET) scans. Yearly neuropsychiatric inventory (Neuropsychiatric Inventory (NPI)/NPI-Questionnaire) data were collected from the study partners at each visit. Mean standard uptake volume ratios (SUVR) normalised to whole cerebellum were obtained. Positive amyloid PET scan was defined as mean SUVR ≥1.17. Fisher's exact test was used to compare frequency and incidence between amyloid positive and amyloid negative subjects. Survival analyses were used to estimate of neuropsychiatric symptoms (NPS) between amyloid positive and amyloid negative subjects. Survival analyses were used to estimate hazard ratios for developing the most common NPS by amyloid status.

RESULTS

No differences in NPS frequency were seen between amyloid positive and amyloid negative NC, SMC, MCI or dementia groups. MCI subjects with amyloid pathology however tended to have greater frequency x severity (FxS) of anxiety, hallucinations, delusions, apathy, disinhibition, irritability, aberrant motor behavior, and appetite, but not agitation, depression, night-time disturbances, or elation. MCI subjects with amyloid pathology were at greater risk for developing apathy, anxiety and agitation over time. Baseline presence of agitation and apathy and new onset agitation, irritability and apathy predicted faster conversion to dementia among MCI subjects.

CONCLUSIONS

Amyloid pathology is associated with greater rate of development of new NPS in MCI. Anxiety and delusions are significant predictors of amyloid pathology. Agitation, irritability and apathy are significant predictors for conversion from MCI to dementia.

Cognitive symptoms of Alzheimer's disease: clinical management and prevention

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by the accumulation of amyloid β in the form of extracellular plaques and by intracellular neurofibrillary tangles, with eventual neurodegeneration and dementia. There is currently no disease-modifying treatment though several symptomatic medications exist with modest benefit on cognition. Acetylcholinesterase inhibitors have a consistent benefit across all stages of dementia; their benefit in mild cognitive impairment and prodromal AD is unproven. Memantine has a smaller benefit on cognition overall which is limited to the moderate to severe stages, and the combination of a cholinesterase inhibitor and memantine may have additional efficacy. Evidence for the efficacy of vitamin E supplementation and medical foods is weak but might be considered in the context of cost, availability, and safety in individual patients. Apparently promising disease-modifying interventions, mostly addressing the amyloid cascade hypothesis of AD, have recently failed to demonstrate efficacy so novel approaches must be considered.

Translational approach to apathy-like behavior in mice: From the practical point of view

Apathy is a pervasive clinical phenomenon that deserves more attention at the translational and pre-clinical levels. To study apathy-like behavior in mice, we relied on an operational definition of apathy: the quantitative reduction of voluntary, goal-directed behaviors. We recently found that the chronic loss of function of a specific cell type (striatal dopamine receptor type 2-expressing medium spiny neurons, D2-MSN) in a restricted region (the ventrolateral striatum, VLS) was sufficient to induce apathy-like behavior in a food-seeking operant task. We further showed that VLS D2-MSN are activated at the preparatory period, and that optogenetic inhibition of VLS D2-MSN during that period resulted in transient decreases in instrumental motivation, strengthening the hypothesis that VLS D2-MSN mediate apathy-like behavior in mice. Mice bearing VLS D2-MSN dysfunction can thus be regarded as an apathy model for future translational studies.

The Newly Normed SKT Reveals Differences in Neuropsychological Profiles of Patients with MCI, Mild Dementia and Depression

The SKT (Syndrom-Kurztest) is a short cognitive performance test assessing deficits of memory and attention in the sense of speed of information processing. The new standardization of the SKT (2015) aimed at improving its sensitivity for early cognitive decline due to dementia in subjects aged 60 or older. The goal of this article is to demonstrate how the neuropsychological test profile of the SKT can be used to provide valuable information for a differential diagnosis between MCI (mild cognitive impairment), dementia and depression. n = 549 patients attending a memory clinic (Nuremberg, Germany) were diagnosed according to ICD-10 and tested with the SKT. The SKT consists of nine subtests, three for the assessment of memory and six for measuring attention in the sense of speed of information processing. The result of the SKT test procedure is a total score, which indicates the severity of overall cognitive impairment. Besides the summary score, two subscores for memory and attention can be interpreted. Using the level of depression as a covariate, statistical comparisons of SKT test profiles between the three patient groups revealed that depressed patients showed more pronounced deficits than MCI patients in all six attention subtests. On the other hand, MCI patients displayed significantly greater mnestic impairment than the depressed group, which was indicated by significant differences in the memory subscore. MCI and dementia patients showed similar deficit patterns dominated by impairment of memory (delayed recall) with MCI patients demonstrating less overall impairment. In sum, the SKT neuropsychological test profiles provided indicators for a differential diagnosis between MCI and beginning dementia vs. depression.

Alcohol drinking exacerbates neural and behavioral pathology in the 3xTg-AD mouse model of Alzheimer's disease

Alzheimer's disease (AD) is a progressive neurodegenerative disorder that represents the most common cause of dementia in the United States. Although the link between alcohol use and AD has been studied, preclinical research has potential to elucidate neurobiological mechanisms that underlie this interaction. This study was designed to test the hypothesis that nondependent alcohol drinking exacerbates the onset and magnitude of AD-like neural and behavioral pathology. We first evaluated the impact of voluntary 24-h, two-bottle choice home-cage alcohol drinking on the prefrontal cortex and amygdala neuroproteome in C57BL/6J mice and found a striking association between alcohol drinking and AD-like pathology. Bioinformatics identified the AD-associated proteins MAPT (Tau), amyloid beta precursor protein (APP), and presenilin-1 (PSEN-1) as the main modulators of alcohol-sensitive protein networks that included AD-related proteins that regulate energy metabolism (ATP5D, HK1, AK1, PGAM1, CKB), cytoskeletal development (BASP1, CAP1, DPYSL2 [CRMP2], ALDOA, TUBA1A, CFL2, ACTG1), cellular/oxidative stress (HSPA5, HSPA8, ENO1, ENO2), and DNA regulation (PURA, YWHAZ). To address the impact of alcohol drinking on AD, studies were conducted using 3xTg-AD mice that express human MAPT, APP, and PSEN-1 transgenes and develop AD-like brain and behavioral pathology. 3xTg-AD and wild-type mice consumed alcohol or saccharin for 4 months. Behavioral tests were administered during a 1-month alcohol-free period. Alcohol intake induced AD-like behavioral pathologies in 3xTg-AD mice including impaired spatial memory in the Morris Water Maze, diminished sensorimotor gating as measured by prepulse inhibition, and exacerbated conditioned fear. Multiplex immunoassay conducted on brain lysates showed that alcohol drinking upregulated primary markers of AD pathology in 3xTg-AD mice: Aβ 42/40 ratio in the lateral entorhinal and prefrontal cortex and total Tau expression in the lateral entorhinal cortex, medial prefrontal cortex, and amygdala at 1-month post alcohol exposure. Immunocytochemistry showed that alcohol use upregulated expression of pTau (Ser199/Ser202) in the hippocampus, which is consistent with late-stage AD. According to the NIA-AA Research Framework, these results suggest that alcohol use is associated with Alzheimer's pathology. Results also showed that alcohol use was associated with a general reduction in Akt/mTOR signaling via several phosphoproteins (IR, IRS1, IGF1R, PTEN, ERK, mTOR, p70S6K, RPS6) in multiple brain regions including hippocampus and entorhinal cortex. Dysregulation of Akt/mTOR phosphoproteins suggests alcohol may target this pathway in AD progression. These results suggest that nondependent alcohol drinking increases the onset and magnitude of AD-like neural and behavioral pathology in 3xTg-AD mice.

Unmet Needs in Pharmacological Treatment of Apathy in Alzheimer's Disease: A Systematic Review

Background: Apathy is one of the most prevalent neuropsychiatric symptoms encountered in Alzheimer’s disease (AD) and may be an early sign in the development of dementia persisting over the disease course. It has been associated with poor disease outcome, impaired daily functioning, and significant caregiver distress. Early diagnosis and timely treatment of apathy in AD are of great importance. However, approved agents for apathy are still missing.

Methods: Within this context, we conducted an extensive electronic search in the databases included in the National Library of Medicine, PsychInfo, and Google Scholar for studies that have investigated the effect of pharmacological treatments in apathy in AD. There were no limitations regarding study design and all care settings were considered for inclusion. Structured measures for level of evidence and study quality were employed to evaluate the results.

Results: A total of 1,607 records were identified; 1,483 records remained after the removal of duplicates and were screened; 166 full-text articles were selected and assessed for eligibility and a remaining 90 unique studies and relevant reviews were included in the qualitative synthesis. Acetylcholinesterase inhibitors, gingko biloba, and methylphenidate were found to be successful in reducing apathy in patients with AD. Methodological heterogeneity in the studies and the small amount of studies where apathy was the primary outcome are limiting factors to assess for group effects.

Conclusions: Pharmacological treatment of apathy in AD is an underexplored field. Standardized and systematic efforts are needed to establish a possible treatment benefit. Elucidating the pathophysiology of apathy and its components or subtypes will inform disease models and mechanistic drug studies that can quantify a benefit from specific agents for specific AD groups.

The Association Between Distinct Frontal Brain Volumes and Behavioral Symptoms in Mild Cognitive Impairment, Alzheimer's Disease, and Frontotemporal Dementia

Our aim was to investigate the association between behavioral symptoms of agitation, disinhibition, irritability, elation, and aberrant motor behavior to frontal brain volumes in a cohort with various neurodegenerative diseases. A total of 121 patients with mild cognitive impairment (MCI, n = 58), Alzheimer's disease (AD, n = 45) and behavioral variant frontotemporal dementia (bvFTD, n = 18) were evaluated with a Neuropsychiatric Inventory (NPI). A T1-weighted MRI scan was acquired for each participant and quantified with a multi-atlas segmentation method. The volumetric MRI measures of the frontal lobes were associated with neuropsychiatric symptom scores with a linear model. In the regression model, we included CDR score and TMT B time as covariates to account for cognitive and executive functions. The brain volumes were corrected for age, gender and head size. The total behavioral symptom score of the five symptoms of interest was negatively associated with the volume of the subcallosal area (β = −0.32, p = 0.002). High disinhibition scores were associated with reduced volume in the gyrus rectus (β = −0.30, p = 0.002), medial frontal cortex (β = −0.30, p = 0.002), superior frontal gyrus (β = −0.28, p = 0.003), inferior frontal gyrus (β = −0.28, p = 0.005) and subcallosal area (β = −0.28, p = 0.005). Elation scores were associated with reduced volumes of the medial orbital gyrus (β = −0.30, p = 0.002) and inferior frontal gyrus (β = −0.28, p = 0.004). Aberrant motor behavior was associated with atrophy of frontal pole (β = −0.29, p = 0.005) and the subcallosal area (β = −0.39, p < 0.001). No significant associations with frontal brain volumes were found for agitation and irritability. We conclude that the subcallosal area may be common neuroanatomical area for behavioral symptoms in neurodegenerative diseases, and it appears to be independent of disease etiology.

Effect of Physical Activity on the Progression of Alzheimer's Disease: The Clinical Research Center for Dementia of South Korea Study

BACKGROUND

There is a lack of research on the effects of physical activity (PA) on the progression of Alzheimer's disease (AD).

OBJECTIVES

We investigated whether PA is associated with progression of dementia and mortality in AD.

METHODS

In the present study, 934 patients with mild-to-moderate AD were included. PA was evaluated using a questionnaire written by the caregiver. The outcome measures were the Clinical Dementia Rating-Sum of Boxes (CDR-SB), Seoul-Instrumental Activities of Daily Living (S-IADL), Caregiver-Administered Neuropsychiatric Inventory (CGA-NPI), a global composite score of neuropsychological subtests, and mortality. They were evaluated annually and received a maximum of three follow-up examinations.

RESULTS

Between-group differences compared with the no PA group in the change of CDR-SB scores were -0.431 (95% CI = -0.824∼-0.039; p = 0.031) for the moderate PA group (150-750 minutes per week of moderate intensity PA), and -1.148 (-1.656∼-0.639; p < 0.001) for the high PA group (>750 minutes per week). As PA increased, there was a significant trend to slow the rate of increase in the CDR-SB, S-IADL, and CGA-NPI scores. The patients with ≥150 minutes per week for each of non-recreational and recreational PAs had a lower risk of mortality compared to those with <150 minutes per week for each of the PAs (hazard ratio 0.22, 95% CI = 0.05∼0.88; p = 0.033).

CONCLUSION

More PA is associated with slower progression of dementia severity, functional decline, and abnormal behavior, and with a lower risk of mortality in AD.

Altered Cingulate Cortex Functional Connectivity in Normal Aging and Mild Cognitive Impairment

Purpose

Resting-state functional Magnetic Resonance Imaging studies revealed that the brain is organized into specialized networks constituted by regions that show a coherent fluctuation of spontaneous activity. Among these networks, the cingulate cortex appears to play a crucial role, particularly in the default mode network, the dorsal attention network and the salience network. In the present study, we mapped the functional connectivity (FC) pattern of different regions of the cingulate cortex: the anterior cingulate cortex, midcingulate cortex and posterior cingulate cortex/retro splenial cortex, which have been in turn divided into a total of 9 subregions. We compared FC patterns of the cingulate subregions in a sample of mild cognitive impairment patients and healthy elderly subjects.

Methods

We enrolled 19 healthy elders (age range: 61-72 y.o.) and 16 Mild cognitive impairment patients (age range 64-87 y.o.). All participants had comparable levels of education (8-10 years) and were neurologically examined to exclude visual and motor impairments, major medical conditions, psychiatric or neurological disorders and consumption of psychotropic drugs. The diagnosis of mild cognitive impairment was performed according to Petersen criteria. Subjects were evaluated with Mini-Mental State Examination, Frontal Assessment Battery, and prose memory (Babcock story) tests. In addition, with functional Magnetic Resonance Imaging, we investigated resting-state network activities.

Results

Healthy elderly, compared to mild cognitive impairment, showed significant increased level of FC for the ventral part of the anterior cingulate cortex in correspondence to the bilateral caudate and ventromedial prefrontal cortex. Moreover, for the midcingulate cortex the healthy elderly group showed increased levels of FC in the somatomotor region, prefrontal cortex, and superior parietal lobule. Meanwhile, the mild cognitive impairment group showed an increased level of FC for the superior frontal gyrus, frontal eye field and orbitofrontal cortex compared to the healthy elderly group.

Conclusion

Our findings indicate that cognitive decline observed in mild cognitive impairment patients damages the global FC of the cingulate cortex, supporting the idea that abnormalities in resting-state activities of the cingulate cortex could be a useful additional tool in order to better understand the brain mechanisms of MCI.

A research proposal testing a new model of ambulation activity among long-term care residents with dementia/cognitive impairment: the study protocol of a prospective longitudinal natural history study

Background

Excessive and patterned ambulation is associated with falls, urinary tract infections, co-occurring delirium and other acute events among long-term care residents with cognitive impairment/dementia. This study will test a predictive longitudinal data model that may lead to the preservation of function of this vulnerable population.

Methods/design

This is a single group, longitudinal study with natural observations. Data from a real-time locating system (RTLS) will be used to objectively and continuously measure ambulation activity for up to 2 years. These data will be combined with longitudinal acute event and functional status data to capture patterns of change in health status over time. Theory-driven multilevel models will be used to test the trajectories of falls and other acute conditions as a function of the ambulation activity and demographic, functional status, gait quality and balance ability including potential mediation and/or moderation effects. Data-driven machine learning algorithms will be applied to run screening of the high dimensional RTLS data together with other variables to discover new and robust predictors of acute events.

Discussion

The findings from this study will lead to the early identification of older adults at risk for falls and the onset of acute medical conditions and interventions for individualized care.

Using Computer Tablets to Improve Moods for Older Adults With Dementia and Interactions With Their Caregivers: Pilot Intervention Study

BACKGROUND

Persons living with dementia represent a significant and growing segment of the older adult (aged 65 years and older) population. They are often challenged expressively and may experience difficulties with sharing their feelings or moods. Availability of, and easy access to, tablets facilitates the use of information and communication technologies (ICTs) as a delivery mechanism for nonpharmacological interventions, especially for persons living with dementia. Evidence of the impact of ICTs in different community settings on mood with older adults and the impact of engagement on their caregivers is needed to promote broader adoption and sustainment of these technologies in the United States.

OBJECTIVE

This study aimed to determine the extent of the effects of tablets on positive mood change and examine the effects of study variables on care recipients' mood changes and caregivers' daily interactions.

METHODS

The tablet intervention was developed and evaluated in five programs. The primary outcome was caregivers' assessment of care recipients' mood (n=1089) before and after a tablet engagement session using an eight-point mood visual analog scale. Session influence on caregivers' daily activities was captured for a subsample of participants (n=542). Frequency distributions were computed for each study variables. Chi-square tests of association were calculated to determine the association of the variables on mood changes for all care recipients, as well as those being treated in skilled nursing facilities and in-home, and then for those that affected caregivers' daily activities.

RESULTS

The study sample comprised 1089 care recipient and caregiver engagement sessions. Cumulatively, 50.78% (553/1089) of care recipients showed a transition from negative to positive moods, whereas another 41.78% (455/1089) maintained an already-positive mood after the caregiver engagement session. Chi-square analyses demonstrated that positive mood changes resulted from using music (χ210=72.9; P<.001), using YouTube as the sole app (χ212=64.5; P<.001), using multiple engagement strategies (χ22=42.8; P<.001), and when cared for in a skilled nursing facility (χ24=236.8; P<.001) across the entire care recipient sample. In addition, although many features of the engagement session positively influenced the caregivers' day, the largest effect was observed when care recipients' mood was considered to have improved following the session (χ24=234.7; P<.001).

CONCLUSIONS

The study is one of the first in the United States to explore the impact of ICTs, in particular managed tablets and Web-based video services that can be used on a tablet through an app, on improving mood in persons living with dementia, and enhancing caregivers' perceptions about their care recipient interactions. Importantly, these pilot data substantiate ICTs as part of a personalized engagement approach, as beneficial alternatives to pharmaceutical interventions for mood enhancement. However, a more comprehensive study that explores the ICT's impact on additional clinical outcomes is needed to confirm these preliminary findings.

Sex differences in Alzheimer disease - the gateway to precision medicine

Alzheimer disease (AD) is characterized by wide heterogeneity in cognitive and behavioural syndromes, risk factors and pathophysiological mechanisms. Addressing this phenotypic variation will be crucial for the development of precise and effective therapeutics in AD. Sex-related differences in neural anatomy and function are starting to emerge, and sex might constitute an important factor for AD patient stratification and personalized treatment. Although the effects of sex on AD epidemiology are currently the subject of intense investigation, the notion of sex-specific clinicopathological AD phenotypes is largely unexplored. In this Review, we critically discuss the evidence for sex-related differences in AD symptomatology, progression, biomarkers, risk factor profiles and treatment. The cumulative evidence reviewed indicates sex-specific patterns of disease manifestation as well as sex differences in the rates of cognitive decline and brain atrophy, suggesting that sex is a crucial variable in disease heterogeneity. We discuss critical challenges and knowledge gaps in our current understanding. Elucidating sex differences in disease phenotypes will be instrumental in the development of a 'precision medicine' approach in AD, encompassing individual, multimodal, biomarker-driven and sex-sensitive strategies for prevention, detection, drug development and treatment.

Call for a Uniform Strategy of Collecting Alzheimer's Disease Costs: A Review and Meta-Analysis

BACKGROUND

There is now a general attempt in developed countries to implement strategic plans to fight against Alzheimer's disease and other dementia disorders. Among others, attention is paid to the issues of registers and calculations of economic burden. Currently available calculations of costs are difficult to compare. The problem is a different breakdown of cost categories and non-unified monitoring of cost types.

OBJECTIVE

The aim of this paper is to note the problem of poor availability and inconsistencies in cost monitoring. Furthermore, the intersection of cost items that are comparable and consistently monitored in expert studies are specified.

METHODS

The Web of Science, Elsevier Science Direct, PubMed, and Scopus databases are used in a systematic review. Two independent reviewers screened the identified records and selected relevant articles published in the period from 2010 to 2016. A meta-analysis of costs is performed in four categories related to patients suffering from Alzheimer's disease.

RESULTS

The resulting estimation of total costs per patient per month through meta-analysis is € 3,896, with 95% CI [2078, 5713]. The highest costs arise from informal care following non-medical and medical care.

CONCLUSION

The results confirm assumption that inconsistencies in cost monitoring of the treatment and care of people with dementia exists in Europe. Homogeneity could be assumed only in the medical costs of severe patients. Heterogeneity is assumed in non-medical costs, informal costs. Cost items should be defined and collected more precisely for future more precise monitoring of the economic burden.

Association between environmental stimulation and apathy in nursing home residents with dementia

OBJECTIVES

Prior research and theories established the link between care environments and apathy. Yet, empirical evidence on how environmental stimulation impacts apathy is lacking. This study examined the association between environmental stimulation and apathy in nursing home residents with dementia.

DESIGN

This repeated-measure study analyzed 104 video observations of staff caregiver-resident interactions.

SETTING

12 nursing homes.

PARTICIPANTS

63 unique staff caregiver-resident dyads that involved 42 caregivers and 44 residents with moderate to severe dementia.

MEASUREMENTS

Second-by-second behavioral coding using Noldus Observer software was conducted to assess apathy and environmental stimulation, using the Person-Environment Apathy Rating scale. The environment subscale includes six items: stimulation clarity, stimulation strength, stimulation specificity, interaction involvement, physical accessibility, and environmental feedback. The apathy subscale includes six items: facial expression, eye contact, physical engagement, purposeful activity, verbal tone, and verbal expression. Multilevel linear models were used for analysis.

RESULTS

Results showed that apathy was not associated with the overall quality of environmental stimulation but was significantly associated with stimulation specificity (coefficient = -2.23, p = 0.049). However, the association was not significant after controlling for resident characteristics (p = 0.082). In addition, higher levels of environmental feedback were associated with lower apathy levels (coefficient = -2.14, p = 0.001). The association remained significant after controlling for resident characteristics (coefficient = -1.65, p = 0.014).

CONCLUSION

Findings reveal that when environmental stimulation is individually tailored and prompts engagement, residents are less apathetic. This study highlights the effect of environmental stimulation on apathy. Future research should explore interventions that modify environmental stimulation to reduce apathy and improve dementia care.

Neurotheranostics as personalized medicines

The discipline of neurotheranostics was forged to improve diagnostic and therapeutic clinical outcomes for neurological disorders. Research was facilitated, in largest measure, by the creation of pharmacologically effective multimodal pharmaceutical formulations. Deployment of neurotheranostic agents could revolutionize staging and improve nervous system disease therapeutic outcomes. However, obstacles in formulation design, drug loading and payload delivery still remain. These will certainly be aided by multidisciplinary basic research and clinical teams with pharmacology, nanotechnology, neuroscience and pharmaceutic expertise. When successful the end results will provide "optimal" therapeutic delivery platforms. The current report reviews an extensive body of knowledge of the natural history, epidemiology, pathogenesis and therapeutics of neurologic disease with an eye on how, when and under what circumstances neurotheranostics will soon be used as personalized medicines for a broad range of neurodegenerative, neuroinflammatory and neuroinfectious diseases.

Inhibition of Polo-like kinase 2 ameliorates pathogenesis in Alzheimer's disease model mice

Alzheimer disease (AD) is a neurodegenerative disorder characterized by pathological hallmarks of neurofibrillary tangles and amyloid plaques. The plaques are formed by aggregation and accumulation of amyloid β (Aβ), a cleavage fragment of amyloid precursor protein (APP). Enhanced neuronal activity and seizure events are frequently observed in AD, and elevated synaptic activity promotes Aβ production. However, the mechanisms that link synaptic hyperactivity to APP processing and AD pathogenesis are not well understood. We previously found that Polo-like kinase 2 (Plk2), a homeostatic repressor of neuronal overexcitation, promotes APP β-processing in vitro. Here, we report that Plk2 stimulates Aβ production in vivo, and that Plk2 levels are elevated in a spatiotemporally regulated manner in brains of AD mouse models and human AD patients. Genetic disruption of Plk2 kinase function reduces plaque deposits and activity-dependent Aβ production. Furthermore, pharmacological Plk2 inhibition hinders Aβ formation, synapse loss, and memory decline in an AD mouse model. Thus, Plk2 links synaptic overactivity to APP β-processing, Aβ production, and disease-relevant phenotypes in vivo, suggesting that Plk2 may be a potential target for AD therapeutics.

Early Intervention with a Multi-Ingredient Dietary Supplement Improves Mood and Spatial Memory in a Triple Transgenic Mouse Model of Alzheimer's Disease

The increasing global burden of Alzheimer's disease (AD) and failure of conventional treatments to stop neurodegeneration necessitates an alternative approach. Evidence of inflammation, mitochondrial dysfunction, and oxidative stress prior to the accumulation of amyloid-β in the prodromal stage of AD (mild cognitive impairment; MCI) suggests that early interventions which counteract these features, such as dietary supplements, may ameliorate the onset of MCI-like behavioral symptoms. We administered a polyphenol-containing multiple ingredient dietary supplement (MDS), or vehicle, to both sexes of triple transgenic (3xTg-AD) mice and wildtype mice for 2 months from 2-4 months of age. We hypothesized that the MDS would preserve spatial learning, which is known to be impaired in untreated 3xTg-AD mice by 4 months of age. Behavioral phenotyping of animals was done at 1-2 and 3-4 months of age using a comprehensive battery of tests. As previously reported in males, both sexes of 3xTg-AD mice exhibited increased anxiety-like behavior at 1-2 months of age, prior to deficits in learning and memory, which did not appear until 3-4 months of age. The MDS did not reduce this anxiety or prevent impairments in novel object recognition (both sexes) or on the water maze probe trial (females only). Strikingly, the MDS specifically prevented 3xTg-AD mice (both sexes) from developing impairments (exhibited by untreated 3xTg-AD controls) in working memory and spatial learning. The MDS also increased sucrose preference, an indicator of hedonic tone. These data show that the MDS can prevent some, but not all, psychopathology in an AD model.

Neuropsychiatric symptoms and executive function impairments in Alzheimer's disease and vascular dementia: The role of subcortical circuits

Neuropsychiatric symptoms (NPS) in dementia are prevalent, under-recognized and little studied regarding their pathophysiological aspects. The pathophysiological mechanism, as well as the possible role of vascular lesions in the genesis of these symptoms, are still matters of debate.

OBJECTIVE

to describe and compare the prevalence and severity of NPS in subjects with Alzheimer's disease (AD) and vascular dementia (VaD).

METHODS

a cross-sectional study involving 82 outpatients, divided into two groups (AD × VaD), was conducted. Patients were submitted to the Cambridge Cognitive Test (CAMCOG), the Clock Drawing Test (CLOX 1 and 2), the Neuropsychiatric Inventory (NPI) and the Clinical Dementia Rating (CDR) scale. Neuroimaging was scored using the de Leon and Fazekas scales.

RESULTS

90.8% of the patients had at least one neuropsychiatric symptom. There were statistical differences on the CLOX test and in the apathy symptoms between AD and VaD groups. Apathy and disinhibition proved more prevalent in patients with higher vascular load.

CONCLUSION

apathy and impaired executive function may reflect vascular damage in subcortical circuits in dementia patients.

Collapsin response mediator protein 5 (CRMP5) causes social deficits and accelerates memory loss in an animal model of Alzheimer's disease

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by several behavioral disturbances, especially cognitive decline and deficits in social competence. Previous studies revealed that decreased social activity would accelerate AD progression, whereas enhanced social interaction could rescue AD-induced memory impairment. Collapsin response mediator protein 5 (CRMP5), which belongs to a family of cytosolic proteins, is abundantly expressed in the brain and is involved in the regulation of neurodevelopment and the pathology of several neuropsychiatric diseases. However, the functions of CRMP5 in AD are still unclear. Here, we demonstrated that 9-month-old 3xTg-AD mice exhibited social behavioral deficits and increased hippocampal CRMP5 levels compared to control (B6129S) mice. Knockdown of CRMP5 reversed the social deficits in 9-month-old 3xTg-AD mice, whereas CRMP5 overexpression decreased social interaction in both 3xTg-AD and control mice at 6 months of age. Interestingly, decreased expression of CRMP5 rescued AD-induced memory impairment, but overexpression of CRMP5 accelerated memory loss only in 3xTg-AD mice. In addition, we found that CRMP5 could regulate surface GluA2 and GluA2 S880 phosphorylation. These results suggest that CRMP5 regulates social behavior via modulation of surface GluA2 trafficking and affects memory performance in 3xTg-AD mice.

The Behavioral and Psychological Symptoms of Dementia in Down Syndrome (BPSD-DS) Scale: Comprehensive Assessment of Psychopathology in Down Syndrome

People with Down syndrome (DS) are prone to develop Alzheimer’s disease (AD). Behavioral and psychological symptoms of dementia (BPSD) are core features, but have not been comprehensively evaluated in DS. In a European multidisciplinary study, the novel Behavioral and Psychological Symptoms of Dementia in Down Syndrome (BPSD-DS) scale was developed to identify frequency and severity of behavioral changes taking account of life-long characteristic behavior. 83 behavioral items in 12 clinically defined sections were evaluated. The central aim was to identify items that change in relation to the dementia status, and thus may differentiate between diagnostic groups. Structured interviews were conducted with informants of persons with DS without dementia (DS, n = 149), with questionable dementia (DS+Q, n = 65), and with diagnosed dementia (DS+AD, n = 67). First exploratory data suggest promising interrater, test-retest, and internal consistency reliability measures. Concerning item relevance, group comparisons revealed pronounced increases in frequency and severity in items of anxiety, sleep disturbances, agitation & stereotypical behavior, aggression, apathy, depressive symptoms, and eating/drinking behavior. The proportion of individuals presenting an increase was highest in DS+AD, intermediate in DS+Q, and lowest in DS. Interestingly, among DS+Q individuals, a substantial proportion already presented increased anxiety, sleep disturbances, apathy, and depressive symptoms, suggesting that these changes occur early in the course of AD. Future efforts should optimize the scale based on current results and clinical experiences, and further study applicability, reliability, and validity. Future application of the scale in daily care may aid caregivers to understand changes, and contribute to timely interventions and adaptation of caregiving.

Sex differences in Alzheimer's disease: Understanding the molecular impact

Alzheimer's disease (AD) is a common neurodegenerative disorder that presents with cognitive impairment and behavioral disturbance. Approximately 5.5 million people in the United States live with AD, most of whom are over the age of 65 with two-thirds being woman. There have been major advancements over the last decade or so in the understanding of AD neuropathological changes and genetic involvement. However, studies of sex impact in AD have not been adequately integrated into the investigation of disease development and progression. It becomes indispensable to acknowledge in both basic science and clinical research studies the importance of understanding sex-specific differences in AD pathophysiology and pathogenesis, which could guide future effort in the discovery of novel targets for AD. Here, we review the latest and most relevant literature on this topic, highlighting the importance of understanding sex dimorphism from a molecular perspective and its association to clinical trial design and development in AD research field.

Review of Programs for Persons Facing Death with Dementia

BACKGROUND

Persons with advanced dementia cannot initiate activities because of the executive dysfunction. The lack of activities was identified as one of the most important factors contributing to behavioral problems of these persons. The unmet needs were boredom/sensory deprivation, loneliness/need for social interaction, and need for meaningful activities. There is a need for activities designed specifically for residents with advanced dementia.

OBJECTIVE

A description of patient's needs and of programs that intend to maintain quality of life for people with dementia and facing death.

DATA SOURCES

A literature review of programs used for persons with advanced dementia and residing in long-term facilities, using the PubMed data base and collateral sources.

RESULTS

Since palliative care is appropriate for persons with advanced dementia, attention has to be paid to three following important aspects of care: Medical issues, behavioral symptoms, and meaningful activities. Medical interventions should be limited to those which have more benefits than burdens, behavioral symptoms should be distinguished according to the context in which they occur, and treated by non-pharmacological interventions that involve meaningful activities. This review describes four programs that may promote the quality of life in persons with advanced dementia and facing death. They are designed for persons with advanced dementia, taking into account their functional impairments. Most of these programs involve short infrequent sessions. In contrast, Namaste Care is a daily extended program of enhanced nursing care that can provide quality of life until the last breath.

CONCLUSIONS

It is possible to maintain quality life for people with advanced dementia if a special program of activities is available.

Clinical Effects of Frontal Behavioral Impairment: Cortical Thickness and Cognitive Decline in Individuals with Subjective Cognitive Decline and Amnestic Mild Cognitive Impairment

BACKGROUND

Frontal behavioral impairment (FrBI) is commonly observed in various degenerative diseases and refers to various behavioral symptoms.

OBJECTIVE

We investigated the effects of the presence of FrBI on cortical thickness, and the longitudinal neuropsychological changes in people in the predementia stage.

METHODS

A total of 794 individuals completed neuropsychological tests and the Frontal Behavioral Inventory (FBI) Questionnaire, and underwent magnetic resonance (MR) scanning. Participants were analyzed and grouped into non-FrBI (FBI = 0) or FrBI (FBI≥1). Cortical thickness was measured on MR images using a surface-based method.

RESULTS

In total, 281 people with subjective cognitive decline (SCD) and 513 with amnestic mild cognitive impairment (aMCI) were assessed for FrBI. Relative to people without FrBI, those with FrBI presented reduced cortical thickness in the frontal, anterior temporal and lateral parietal regions (p < 0.05, FDR corrected). People with FrBI developed Alzheimer's disease, rather than behavioral variant frontotemporal dementia, as observed over seven years. Mixed effects models reported that people with FrBI have greater cognitive decline than those with non-FrBI in multiple domains, including language, memory, and executive functions (p < 0.05, FDR corrected). Furthermore, while negative FrBI symptoms (e.g., deficit behaviors) were associated with greater declines in multiple domains, positive FrBI symptoms (e.g., disinhibition symptoms) were related to declines in visuospatial function and verbal memory. Finally, the occurrence of both types of symptoms correlated with multi-domain cognitive decline.

CONCLUSIONS

FrBI predicted worse clinical outcomes, including reduced cortical thickness and cognitive decline, which are not necessarily specific to frontal dysfunction.

Why Do They Just Sit? Apathy as a Core Symptom of Alzheimer Disease

OBJECTIVE

Apathy is common in Alzheimer disease (AD) and has a far-reaching impact on patients' clinical course and management needs. However, it is unclear if apathy is an integral component of AD or a manifestation of depression in cognitive decline. This study aims to examine interrelationships between apathy, depression, and function.

METHODS

This was a cross-sectional study of well-characterized AD patients in the National Alzheimer's Coordinating Center Uniform Data Set with a Clinical Dementia Rating (CDR) between 0.5 and 2. Participants' function was measured using the Functional Assessment Questionnaire. Apathy and depression were measured using clinician judgment and informant-reported Neuropsychiatric Inventory-Questionnaire. Dementia severity was categorized by CDR.

RESULTS

Sample included 7,679 participants (55.7% men) with a mean (standard deviation) age of 74.9 (9.7) years; 3,197 (41.6%) had apathy based on clinician judgment. Among those with apathy, approximately half had no depression. Presence of apathy was associated with 21%, 10%, and 3% worsening in function compared with those without apathy in CDR 0.5, 1, and 2 groups, respectively. Depression was not independently associated with functional status. Results revealed no interaction between apathy and depression.

CONCLUSION

Apathy, but not depression, was significantly associated with worse function, with the strongest effects in mild dementia. Results emphasize the need for separate assessments of apathy and depression in the evaluation and treatment of patients with dementia. Understanding their independent effects on function will help identify patients who may benefit from more targeted management strategies.

Neuropsychiatric symptoms differently affect mild cognitive impairment and Alzheimer's disease patients: a retrospective observational study

Alzheimer's disease (AD) is the most common form of dementia characterized by the prevalent memory impairment. Mild cognitive impairment (MCI) may represent the early stage of AD, in particular when MCI patients show biomarkers consistent with AD pathology (MCI due to AD). Neuropsychiatric symptoms (NPS) frequently affect both MCI and AD patients. Cerebrospinal-fluid (CSF) tau and β-amyloid₄₂ (Aβ₄₂) levels are actually considered the most sensitive and specific biomarkers for AD neurodegeneration. In the present retrospective observational study, we evaluated CSF biomarkers and neuropsychological data (also including NPS measured by the neuropsychiatric inventory-NPI) in a population of patients affected by MCI due to AD compared with mild to moderate AD patients. We documented higher NPI scores in MCI compared with AD patients. In particular, sub-items related to sleep, appetite, irritability, depression, and anxiety were higher in MCI than AD. We also found the significant correlation between NPS and CSF AD biomarkers in the whole population of MCI and AD patients. Consistently, t-tau/Aβ₄₂ ratio correlated with NPS in all the MCI and AD patients. These results suggest the more prevalent occurrence of NPS in MCI patients showing AD pathology and converting to dementia than AD patients. Moreover, a more significant degree of AD neurodegeneration, featured by high t-tau/Aβ₄₂ ratio, correlated with more severe NPS, thus supposing that in MCI and AD patients a more extensive AD neurodegeneration is related to more severe behavioral disturbances.

Effect of Exercise on Behavioral Symptoms and Pain in Patients With Dementia Living in Nursing Homes

OBJECTIVES

Examine the effects of a 6-month exercise intervention on neuropsychiatric symptoms, pain, and medication consumption in older people with dementia (PWD) living in nursing homes (NH).

METHODS

Ninety-one older PWD living in NH performed a 6-month structured exercise intervention (n = 44) or a social activity intervention (n = 47). Neuropsychiatric symptoms were measured by the neuropsychiatric inventory (NPI), pain was assessed using the Algoplus scale, and dementia-related drug prescriptions were obtained for all participants.

RESULTS

Between-group analysis found a nonsignificant difference that could be of clinical relevance: a 4-point difference in the NPI and 1.3-point difference in the reduction of the number of medications favoring exercisers. No significant differences were found for pain, and a trend was found for an increase in medication consumption in the social group.

CONCLUSION

Exercise effects did not differ from social intervention effects on neuropsychiatric symptoms, pain, and medication consumption in older PWD living in NH.

Digital biomarkers for Alzheimer's disease: the mobile/ wearable devices opportunity

Alzheimer's Disease (AD) represents a major and rapidly growing burden to the healthcare ecosystem. A growing body of evidence indicates that cognitive, behavioral, sensory, and motor changes may precede clinical manifestations of AD by several years. Existing tests designed to diagnose neurodegenerative diseases, while well-validated, are often less effective in detecting deviations from normal cognitive decline trajectory in the earliest stages of the disease. In the quest for gold standards for AD assessment, there is a growing interest in the identification of readily accessible digital biomarkers, which harness advances in consumer grade mobile and wearable technologies. Topics examined include a review of existing early clinical manifestations of AD and a path to the respective sensor and mobile/wearable device usage to acquire domain-centric data towards objective, high frequency and passive digital phenotyping.

Maintenance of occupational therapy (OT) for dementia: protocol of a multi-center, randomized controlled and pragmatic trial

Background

There is a growing interest in developing tailored non-pharmacological strategies to face patients’ needs in dementia. Occupational therapy (OT) may contribute to promote self-empowerment of both patients and caregivers. France has implemented nationwide OT over a short-term period of 3/4 months. The main objective of the MathéoAlz study is to measure the impact of maintaining OT over 4 supplementary months on patients’ neuropsychiatric symptoms.

Methods/design

The MatheoAlz trial (Maintenance of Occupational Therapy in Alzheimer’s disease) is a multi-center, pragmatic randomized controlled trial testing maintenance of OT over 4 supplementary months compared to routine OT delivered as recommended. This paper describes the study protocol. MatheoAlz plans to enroll 240 dyads, i.e. dementia patients and caregivers, whose main inclusion criteria are: prescription for routine OT, patients with mild or moderate dementia, living at home, receiving support from an informal caregiver. The study will compare a control group of patients benefiting from 12 to 15 initial sessions of OT over 3/4 months and an intervention group of patients benefiting from these initial sessions plus 8 extra home sessions over 4 supplementary months. The main outcome is the patient’s neuropsychiatric symptoms assessed by the Neuropsychiatric Inventory at 8 months. Several clinical outcomes and economic consequences are measured at 4, 8 and 12 months.

Discussion

This is the first trial designed to assess the specific impact of the maintaining OT on the patients’ neuropsychiatric symptoms burden. The results will inform policymakers on strategies to implement in the near future.

Trial registration

This trial was registered at ClinicalTrials.gov on February 16, 2018, identifier: NCT03435705.

Predictions of Alzheimer's disease treatment and care costs in European countries

Background

Given the increasing lifespan of the elderly and the higher proportion of older people in the global population, the incidence rate of neurodegenerative diseases is increasing. The aim of this study is to evaluate, by means of computer simulations, developments in the costs of treating and caring for people suffering from Alzheimer’s disease (AD) in the EU 28 by 2080, while assuming the introduction of drug administrations at various disease stages.

Methods

Impact analysis leverages a mathematical model that compares five different population development scenarios when introducing different types of drugs to the scenarios but without changing the treatment. Changes in the economic burden are considered as of 2023, when new drugs are expected to enter the market.

Findings

The results of the simulations show that by prolonging the length of a person’s ‘stay’ in the Mild, Moderate, or Severe stage, the total cost of care for all persons with AD will increase by 2080. For individual scenarios, the percentage of patients and costs increased as follows: Mild by one year, by 10.61%; Mild by two years, by 17.73%; Moderate by one year, by 16.79%; Moderate by two years, by 34.88%; and Severe by one year, by 23.79%. The change in cost development when prolonging the stay in the Mild cognitive impairment stage (by lowering the incidence by 10%, 30%, or 50%) reduced the cost (by 4.88%, 16.78% and 32.48%, respectively).

Interpretation

The results unambiguously show that any intervention prolonging a patient’s stay in any stage will incur additional care costs and an increase in the number of persons with AD. Therefore, extending lifespan is important in terms of improving the quality of life of patients, and the introduction of new drugs must consider the additional costs imposed upon society.

The current understanding of overlap between characteristics of HIV-associated neurocognitive disorders and Alzheimer's disease

The advent of effective antiretroviral medications (ARVs) has led to an aging of the HIV population with approximately 50% of people with HIV (PWH) being over the age of 50 years. Neurocognitive complications, typically known as HIV-associated neurocognitive disorders (HAND), persist in the era of ARVs and, in addition to risk of HAND, older PWH are also at risk for age-associated, neurodegenerative disorders including Alzheimer's disease (AD). It has been postulated that risk for AD may be greater among PWH due to potential compounding effects of HIV and aging on mechanisms of neural insult. We are now faced with the challenge of disentangling AD from HAND, which has important prognostic and treatment implications given the more rapidly debilitating trajectory of AD. Herein, we review the evidence to date demonstrating both parallels and differences in the profiles of HAND and AD. We specifically address similarities and difference of AD and HAND as it relates to (1) neuropsychological profiles (cross-sectional/longitudinal), (2) AD-associated neuropathological features as evidenced from neuropathological, cerebrospinal fluid and neuroimaging assessments, (3) biological mechanisms underlying cortical amyloid deposition, (4) parallels in mechanisms of neural insult, and (5) common risk factors. Our current understanding of the similarities and dissimilarities of AD and HAND should be further delineated and leveraged in the development of differential diagnostic methods that will allow for the early identification of AD and more suitable and effective treatment interventions among graying PWH.

In vivo characterization of a novel norepinephrine transporter PET tracer [18F]NS12137 in adult and immature Sprague-Dawley rats

Norepinephrine modulates cognitive processes such as working and episodic memory. Pathological changes in norepinephrine and norepinephrine transporter (NET) function and degeneration of the locus coeruleus produce irreversible impairments within the whole norepinephrine system, disrupting cognitive processes. Monitoring these changes could enhance diagnostic accuracy and support development of novel therapeutic components for several neurodegenerative diseases. Thus, we aimed to develop a straightforward nucleophilic fluorination method with high molar activity for the novel NET radiotracer [¹⁸F]NS12137 and to demonstrate the ability of [¹⁸F]NS12137 to quantify changes in NET expression.

Methods: We applied an ¹⁸F-radiolabeling method in which a brominated precursor was debrominated by nucleophilic ¹⁸F-fluorination in dimethyl sulfoxide. Radiolabeling was followed by a deprotection step, purification, and formulation of the radiotracer. The [¹⁸F]NS12137 brain uptake and distribution were studied with in vivo PET/CT and ex vivo autoradiography using both adult and immature Sprague-Dawley rats because postnatal NET expression peaks at 10-20 days post birth. The NET specificity for the tracer was demonstrated by pretreatment of the animals with nisoxetine, which is well-known to have a high affinity for NET.

Results: [¹⁸F]NS12137 was successfully synthesized with radiochemical yields of 18.6±5.6%, radiochemical purity of >99%, and molar activity of >500 GBq/μmol at the end of synthesis. The in vivo [¹⁸F]NS12137 uptake showed peak standard uptake values (SUV) of over 1.5 (adult) and 2.2 (immature) in the different brain regions. Peak SUV/30 min and peak SUV/60 min ratios were calculated for the different brain regions of the adult and immature rats, with a peak SUV/60 min ratio of more than 4.5 in the striatum of adult rats. As expected, in vivo studies demonstrated uptake of the tracer in brain areas rich in NET, particularly thalamus, neocortex, and striatum, and remarkably also in the locus coeruleus, a quite small volume for imaging with PET. The uptake was significantly higher in immature rats compared to the adult animals. Ex vivo studies using autoradiography showed very strong specific binding in NET-rich areas such as the locus coeruleus and the bed nucleus of the stria terminalis, and high binding in larger grey matter areas such as the neocortex and striatum. The uptake of [¹⁸F]NS12137 was dramatically reduced both in vivo and ex vivo by pretreatment with nisoxetine, demonstrating the specificity of binding.

Conclusions: [¹⁸F]NS12137 was synthesized in good yield and high molar activity and demonstrated the characteristics of a good radiotracer, such as good brain penetration, fast washout, and high specific binding to NET.

The Physical Burden of Immunoperception

The previous chapter introduced the ImmunoEmotional Regulatory System (IMMERS). Also, there was a brief discussion about psychological states/psychiatric disorders that so far have been linked to the IMMERS. The present chapter considers another aspect of the IMMERS in which physiological states/physical diseases can be fit to the IMMERS.

APOE ɛ4/ɛ4 Is Associated with Aberrant Motor Behavior Through Both Lewy Body and Cerebral Amyloid Angiopathy Pathology in High Alzheimer's Disease Pathological Load

BACKGROUND

Aberrant motor behavior (AMB) is a neuropsychiatric symptom (NPS) prevalent in Alzheimer's disease (AD), known to cause great distress to both patients and caregivers. Apolipoprotein E4 (APOE4) is the most important genetic predictor of AD, and it has been associated with high NPS prevalence.

OBJECTIVE

To investigate the neuropathological substrates and risk factors associated with AMB in AD patients.

METHODS

Cases with Braak stage I-II and CERAD 0-1 were classified as Low AD (LAD), while Braak stage III-IV and CERAD 2 were grouped as Intermediate AD (IAD). Cases with Braak stage V-VI and CERAD 3 were classified as High AD (HAD) in accordance with NIA-Reagan criteria. All cases were stratified by APOE genotype, yielding No ɛ4 & ɛ4 and ɛ4/ɛ4 groups depending on ɛ4 copy number within APOE. Presence of AMB was assessed using NPI-Q.

RESULTS AND CONCLUSION

AMB increased in parallel with CERAD and Braak & Braak scores. Hypercholesterolemia, but no other cardiovascular risk factors, was associated with AMB in HAD. AMB prevalence in HAD was significantly increased in the presence of two APOEɛ4 alleles as compared to No ɛ4 & ɛ4. The relationship between homozygous APOE4 and AMB was strongly associated with the presence of both Lewy bodies and cerebral amyloid angiopathy pathologies in both sexes.

[Premorbid personality as a risk factor in the appearance of psychological and behavioural symptoms of dementia: Systematic review]

The aetiology of behavioural and psychological symptoms of dementia (BPSD) is defined by a diversity of factors, and recent studies suggest that premorbid personality could be a risk factor for BPSD. This study aimed to review studies on the relationship between premorbid personality and BPSD. Studies were identified using PsycInfo, MedLine, and PubMed. The searches combined terms for premorbid personality, dementia and BPSD. Ten studies have been included in this review. Eight out of ten studies show a relationship between premorbid personality and BPSD. Neuroticism is associated with behavioural disturbances and anxiety. Extraversion is associated with wandering. Low agreeableness is associated with affective disturbance and aggression-related behaviours and high agreeableness is associated with wandering. The studies found no congruent results for openness and conscientiousness. In conclusion, premorbid personality may increase the risk of developing BPSD during the course of the disease. Even so, the relationship between personality and BPSD is complex due to multifactorial aetiology.

A Novel hAPP/htau Mouse Model of Alzheimer's Disease: Inclusion of APP With Tau Exacerbates Behavioral Deficits and Zinc Administration Heightens Tangle Pathology

The brains of those with Alzheimer's disease have amyloid and tau pathology; thus, mice modeling AD should have both markers. In this study, we characterize offspring from the cross of the J20 (hAPP) and rTg4510 (htau) strains (referred to as dual Tg). Behavior was assessed at both 3.5 and 7 months, and biochemical differences were assessed at 8 months. Additionally, mice were placed on zinc (Zn) water or standard lab water in order to determine the role of this essential biometal. Behavioral measures examined cognition, emotion, and aspects of daily living. Transgenic mice (dual Tg and htau) showed significant deficits in spatial memory in the Barnes Maze at both 3.5 and 7 months compared to controls. At 7 months, dual Tg mice performed significantly worse than htau mice (p < 0.01). Open field and elevated zero maze (EZM) data indicated that dual Tg and htau mice displayed behavioral disinhibition compared to control mice at both 3.5 and 7 months (p < 0.001). Transgenic mice showed significant deficits in activities of daily living, including burrowing and nesting, at both 3.5 and 7 months compared to control mice (p < 0.01). Dual Tg mice built very poor nests, indicating that non-cognitive tasks are also impacted by AD. Overall, dual Tg mice demonstrated behavioral deficits earlier than those shown by the htau mice. In the brain, dual Tg mice had significantly less free Zn compared to control mice in both the dentate gyrus and the CA3 of the hippocampus (p < 0.01). Dual Tg mice had increased tangles and plaques in the hippocampus compared to htau mice and the dual Tg mice given Zn water displayed increased tangle pathology in the hippocampus compared to htau mice on Zn water (p < 0.05). The dual Tg mouse described here displays pathology reminiscent of the human AD condition and is impaired early on in both cognitive and non-cognitive behaviors. This new mouse model allows researchers to assess how both amyloid and tau in combination impact behavior and brain pathology.

Psychometric Properties of a Flanker Task in a Sample of Patients with Dementia: A Pilot Study

Background/Aims

Reliable and valid neuropsychological tests for patients with dementia are scarce. To improve the assessment of attention and inhibitory control in dementia, we determined the feasibility, test-retest reliability, and validity of a Flanker task.

Methods

Participants with all-cause diagnosed dementia (n = 22, mean age 84 years; mean Mini-Mental State Examination [MMSE] score = 19.4) performed a computerized Flanker task twice within 7 days. The Flanker task required participants to indicate the direction of target arrows flanked by congruent or incongruent arrows. Number of completed trials, accuracy, and reaction times (RTs) were recorded, and interference scores were calculated from basic scores. We examined the psychometric properties of the Flanker task and its relationship with the MMSE and Stroop test.

Results

The Flanker task was feasible. Test-retest reliability was good for number of correct answers and RTs, and fair to poor for accuracy and the interference scores. The correlation of the Flanker task with Stroop and MMSE performance was fair to poor.

Conclusion

The Flanker task appears to be feasible, and a reliable and valid measure of selective attention. Although the test-retest reliability for the Flanker RT interference measure was fair, future studies need to confirm its validity to measure inhibitory control in patients with dementia.

[The behavioral and psychological symptoms of dementia in down syndrome (BPSD-DS) scale: comprehensive assessment of psychopathology in down syndrome]

Behavioral and psychological symptoms of dementia (BPSD) have not been comprehensively studied in people with Down syndrome, despite their high risk on dementia. A novel evaluation scale was developed to identify the nature, frequency and severity of behavioral changes (83 behavioral items in 12 clinically defined sections). Central aim was to identify items that change in relation to the dementia status. Structured interviews were conducted with informants of people with Down syndrome without dementia (DS, N = 149), with questionable dementia (DS + TD, N = 65) and with diagnosed dementia (DS + AD, N = 67). Group comparisons showed a pronounced increase in frequency and severity of items about anxiety, sleep disturbances, agitation & stereotypical behavior, aggression, apathy, depressive symptoms, and, eating/drinking behavior. The proportion of individuals presenting an increase was highest in the DS + AD group and lowest in the DS group. Interestingly, among DS + TD individuals, a substantial proportion already presented increased anxiety, sleep disturbances, apathy and depressive symptoms, suggesting that these changes may be early alarm signals of dementia. The scale may contribute to a better understanding of the changes, adapting daily care/support, and providing suitable therapies to people with Down syndrome. The scale needs to be optimized based on the results and experiences. The applicability, reliability and validity require further study.

The anatomy of apathy: A neurocognitive framework for amotivated behaviour

Apathy is a debilitating syndrome associated with many neurological disorders, including several common neurodegenerative diseases such as Parkinson's disease and Alzheimer's disease, and focal lesion syndromes such as stroke. Here, we review neuroimaging studies to identify anatomical correlates of apathy, across brain disorders. Our analysis reveals that apathy is strongly associated with disruption particularly of dorsal anterior cingulate cortex (dACC), ventral striatum (VS) and connected brain regions. Remarkably, these changes are consistent across clinical disorders and imaging modalities. Review of the neuroimaging findings allows us to develop a neurocognitive framework to consider potential mechanisms underlying apathy. According to this perspective, an interconnected group of brain regions - with dACC and VS at its core - plays a crucial role in normal motivated behaviour. Specifically we argue that motivated behaviour requires a willingness to work, to keep working, and to learn what is worth working for. We propose that deficits in any one or more of these processes can lead to the clinical syndrome of apathy, and outline specific approaches to test this hypothesis. A richer neurobiological understanding of the mechanisms underlying apathy should ultimately facilitate development of effective therapies for this disabling condition.

Behavioral Problems and Dementia

Behavioral problems decrease quality of life of people with dementia and their care providers. Three main consequences of dementia are functional impairment and in some cases also mood disorders and psychosis. These consequences, alone or in combination, result in 3 main behavioral problems: apathy, agitation, and rejection of care/aggression. Nonpharmacologic management strategies include meaningful activities and individualized comfort care, for example, Namaste Care. If needed, pharmacologic management should concentrate on treatment of main dementia consequences, especially depression, instead of treating secondary symptoms, for example, insomnia. Use of antipsychotics should be minimized but antipsychotics may be necessary for augmentation of antidepressants.

Relationship between the number of behavioral symptoms in dementia and caregiver distress: what is the tipping point?

ABSTRACTBackground:Behavioral and psychological symptoms of dementia (BPSD) are a primary manifestation of brain dysfunction in dementia and a great challenge in caregiving. While BPSD are historically associated with caregiver distress, it is unclear whether there is an identifiable point where BPSD number is associated with heightened caregiver distress. The purpose of this study was to determine if such a tipping point exists to assist clinicians in identifying caregiver compromise.

METHODS

Analyses were performed with three datasets totaling 569 community-dwelling persons with dementia and their caregivers. Each included identical demographic, BPSD, cognitive, and caregiver well-being measures. Linear regression was performed with 16 BPSD symptoms on caregiver well-being measures and predictive values determined with receiver operating characteristic (ROC) curves and pre-defined scores for clinically significant distress.

RESULTS

Of the 569 persons with dementia, 549 (96%) displayed at least one BPSD, mean of 5.7 (SD = 3.06) symptoms in the past month. After controlling for covariates, BPSD symptom number was significantly associated with caregiver depression and burden (p < 0.01 for both models). Findings indicate ≥ 4 BPSD has strong predictive values for depression (sensitivity 85%, specificity 44%, area under ROC curve 0.62, p < 0.01), and burden (sensitivity 84%, specificity 43%, area under ROC curve 0.67, p < 0.01).

CONCLUSIONS

Caring for persons with four or more BPSD appears to reflect a tipping point for clinically meaningful distress. Findings have implications for clinicians working with persons with dementia and their caregivers and suggest need for continuous monitoring of BPSD and identification of at risk caregivers.

Brain Perfusion Correlates of Apathy in Alzheimer's Disease

Background and Purpose

Apathy is one of the most common neuropsychiatric symptoms in patients with Alzheimer's disease (AD). It may have adverse impacts on the progression of AD. However, its neurobiological underpinnings remain unclear. The objective of this study was to investigate differences in regional cerebral blood flow (rCBF) between AD patients with apathy and those without apathy.

Methods

Sixty-six apathetic AD patients and 66 AD patients without apathy completed Neuropsychiatric Inventory (NPI) and underwent technetium-99m hexamethylpropylene amine oxime single-photon emission computed tomography (SPECT) scans. Voxel-wise differences in rCBF between the 2 groups were examined. Association between rCBF and levels of apathy in the apathetic group was also assessed.

Results

AD patients with apathy showed lower rCBF in the bilateral orbitofrontal cortex, left putamen, left nucleus accumbens, left thalamus, and bilateral insula than those without (all p<0.005). Mean perfusion across all significant clusters showed a negative linear correlation with NPI apathy score in AD patients with apathy (β=-0.25; p=0.04).

Conclusions

Hypoperfusion in the prefrontal, striatal, and insular areas may be neural correlates of apathy in AD patients.

Managing Aged Animals in Zoos to Promote Positive Welfare: A Review and Future Directions

Simple Summary

Many animals experience physical and behavioral changes as they age. Age-related changes in physical or mental ability can limit the opportunities for animals to experience positive well-being. As animals in zoos are living longer than ever, understanding common physical, cognitive, and behavioral changes associated with ageing across species can help inform management practices. This review aggregates information about common age-related changes across a wide number of species, discusses the potential welfare impacts of these changes for ageing animals, and suggests methods for caretakers to maximize positive welfare opportunities for ageing animals under human care.

Abstract

Improvements in veterinary care, nutrition, and husbandry of animals living in zoos have led to an increase in the longevity of these animals over the past 30 years. In this same time period, the focus of animal welfare science has shifted from concerns over mitigating negative welfare impacts to promoting positive welfare experiences for animals. For instance, providing opportunities for animals to exert agency, solve problems, or acquire rewards are all associated with positive welfare outcomes. Many common age-related changes result in limitations to opportunities for positive welfare experiences, either due to pain or other physical, cognitive, or behavioral limitations. This review aggregates information regarding common age-related physical and behavioral changes across species, discusses how age-related changes may limit positive welfare opportunities of aged animals in human care, and suggests potential management methods to help promote positive welfare for animals at all life stages in zoos and aquariums.