Neuropsychiatric Symptoms in Alzheimer's Disease Are the Main Determinants of Functional Impairment in Advanced Everyday Activities

Prevalence of mild behavioural impairment and its association with cognitive and functional impairment in normal cognition, mild cognitive impairment, and mild Alzheimer's dementia

BACKGROUND

Mild behavioural impairment (MBI) is an emergent and persistent neuropsychiatric symptom (NPS) in subjects aged 50 and older who are at risk for cognitive decline. We examined the prevalence of MBI across the spectrum from cognitively normal (CN), mild cognitive impairment (MCI), to dementia, and further investigated the association between the MBI domain and cognitive and functional impairment.

METHOD

MBI was assessed in 2337 elderly patients in the Alzheimer's Disease Neuroimaging Initiative database (mean age, 73.04 years; 52.8% male). Among the subjects, 868 (37.1%) had normal cognition, 1066 (45.6%) had MCI, and 403 (17.2%) had mild Alzheimer's dementia (AD). MBI was evaluated in accordance with the Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment diagnostic criteria for MBI, utilising the Neuropsychiatric Inventory. We compared the prevalence of the MBI domain with CN using multinominal logistic regression analysis and further quantified the magnitude of the association between MCI/AD and the MBI domains by calculating the population attributable risk (PAR). We assessed the association between the MBI domains and cognitive and functional impairment using simultaneous linear regression analysis.

RESULTS

The most common MBI domains in each diagnostic group were affective dysregulation followed by impulse dyscontrol, decreased motivation, social inappropriateness, and abnormal perception or thought content. The PARs for MBI domains in subjects with MCI or AD were respectively: 16.60% and 24.34% for affective dysregulation; 3.72% and 18.06% for impulse dyscontrol; 4.78% and 14.13% for decreased motivation, 1.91% and 2.29% for social inappropriateness; and 0.68% and 3.85% for abnormal perception or thought content. All MBI domains except for social inappropriateness were significantly associated with a higher 11-item Alzheimer's Disease Assessment Scale-Cognitive Subscale total score. All MBI domains were significantly associated with a higher Functional Activities Questionnaire total score.

CONCLUSION

Our findings show that MBI is highly prevalent across subjects with CN, MCI, and AD and is associated with cognitive and functional decline. MBI could be a crucial clinical phenotype relevant to the risk of cognitive and functional impairment, and provides a useful dimension pertinent to diagnostic approaches.

A Multidimensional, Person-Centered Framework for Functional Assessment in Dementia: Insights from the 'What', 'How', 'To Whom', and 'How Much' Questions

Dementia is a syndrome characterized by cognitive and neuropsychiatric symptoms associated with progressive functional decline (FD). FD is a core diagnostic criterion for dementia, setting the threshold between its prodromal stages and the full-blown disease. The operationalization of FD continues to generate a great deal of controversy. For instance, the threshold of FD for the diagnosis of dementia varies across diagnostic criteria, supporting the need for standardization of this construct. Moreover, there is a need to reconsider how we are measuring FD to set boundaries between normal aging, mild cognitive impairment, and dementia. In this paper, we propose a multidimensional framework that addresses outstanding issues in the assessment of FD: i) What activities of daily living (ADLs) are necessary to sustain an independent living in aging? ii) How to assess FD in individuals with suspected neurocognitive disorders? iii) To whom is the assessment directed? and iv) How much does FD differentiate healthy aging from mild and major neurocognitive disorders? Importantly, the To Whom Question introduces a person-centered approach that regards patients and caregivers as active agents in the assessment process of FD. Thus, once impaired ADLs have been identified, patients can indicate how significant such impairments are for them in daily life. We envisage that this new framework will guide future strategies to enhance functional assessment and treatment of patients with dementia and their caregivers.

Heterogeneity of Response to Methylphenidate in Apathetic Patients in the ADMET 2 Trial

OBJECTIVE

The Apathy in Dementia Methylphenidate Trial 2 (ADMET 2) found that methylphenidate was effective in treating apathy with a small-to-medium effect size but showed heterogeneity in response. We assessed clinical predictors of response to help determine individual likelihood of treatment benefit from methylphenidate.

DESIGN

Univariate and multivariate analyses of 22 clinical predictors of response chosen a priori.

SETTING

Data from the ADMET 2 randomized, placebo controlled multi-center clinical trial.

PARTICIPANTS

Alzheimer's disease patients with clinically significant apathy.

MEASUREMENTS

Apathy assessed with the Neuropsychiatric Inventory apathy domain (NPI-A).

RESULTS

In total, 177 participants (67% male, mean [SD] age 76.4 [7.9], mini-mental state examination 19.3 [4.8]) had 6-months follow up data. Six potential predictors met criteria for inclusion in multivariate modeling. Methylphenidate was more efficacious in participants without NPI anxiety (change in NPI-A -2.21, standard error [SE]:0.60) or agitation (-2.63, SE:0.68), prescribed cholinesterase inhibitors (ChEI) (-2.44, SE:0.62), between 52 and 72 years of age (-2.93, SE:1.05), had 73-80 mm Hg diastolic blood pressure (-2.43, SE: 1.03), and more functional impairment (-2.56, SE:1.16) as measured by the Alzheimer's Disease Cooperative Study Activities of Daily Living scale.

CONCLUSION

Individuals who were not anxious or agitated, younger, prescribed a ChEI, with optimal (73-80 mm Hg) diastolic blood pressure, or having more impaired function were more likely to benefit from methylphenidate compared to placebo. Clinicians may preferentially consider methylphenidate for apathetic AD participants already prescribed a ChEI and without baseline anxiety or agitation.

An Update on Apathy in Alzheimer's Disease

Apathy is a complex multi-dimensional syndrome that affects up to 70% of individuals with Alzheimer's disease (AD). Whilst many frameworks to define apathy in AD exist, most include loss of motivation or goal-directed behaviour as the central feature. Apathy is associated with significant impact on persons living with AD and their caregivers and is also associated with accelerated cognitive decline across the AD spectrum. Neuroimaging studies have highlighted a key role of fronto-striatial circuitry including the anterior cingulate cortex (ACC), orbito-frontal cortex (OFC) and associated subcortical structures. Importantly, the presence and severity of apathy strongly correlates with AD stage and neuropathological biomarkers of amyloid and tau pathology. Following from neurochemistry studies demonstrating a central role of biogenic amine neurotransmission in apathy syndrome in AD, recent clinical trial data suggest that apathy symptoms may improve following treatment with agents such as methylphenidate-which may have an important role alongside emerging non-pharmacological treatment strategies. Here, we review the diagnostic criteria, rating scales, prevalence, and risk factors for apathy in AD. The underlying neurobiology, neuropsychology and associated neuroimaging findings are reviewed in detail. Finally, we discuss current treatment approaches and strategies aimed at targeting apathy syndrome in AD, highlighting areas for future research and clinical trials in patient cohorts.

Toward the optimized assessment of clinical outcomes in studies of novel treatments for Alzheimer's disease

INTRODUCTION

Alzheimer's disease (AD) is characterized by a progressive decline in cognition and daily function, leading to a greater need for caregiver support. Clinical disease is segmented into a preclinical stage, mild cognitive impairment, and mild, moderate, and severe stages of Alzheimer's dementia. Although AD trials enroll participants at various stages of illness, treatment efficacy is often assessed using endpoints based on measures of outcomes that are held fixed across disease stages. We hypothesize that matching the primary outcomes measured in the endpoint hierarchy to the stage of disease targeted by the trial will increase the likelihood of detecting true treatment benefits.

AREAS COVERED

We discuss current approaches to assessing clinical outcomes in AD trials, followed by a consideration of how effect detection can be improved by linking the stage of AD to the endpoints that most likely reflect stage-specific disease progression.

EXPERT OPINION

Failing to account for stage-specific relevance and sensitivity of clinical outcomes may be one factor that contributes to trial failures in AD. Given the history of failure, experts have begun to scrutinize the relevance and sensitivity of outcomes as a potentially modifiable barrier to successful trials. To this end, we present a framework for refining trial endpoint selection and evaluation.

Multiple Cognitive and Behavioral Factors Link Association Between Brain Structure and Functional Impairment of Daily Instrumental Activities in Older Adults

OBJECTIVE

Functional impairment in daily activity is a cornerstone in distinguishing the clinical progression of dementia. Multiple indicators based on neuroimaging and neuropsychological instruments are used to assess the levels of impairment and disease severity; however, it remains unclear how multivariate patterns of predictors uniquely predict the functional ability and how the relative importance of various predictors differs.

METHOD

In this study, 881 older adults with subjective cognitive complaints, mild cognitive impairment (MCI), and dementia with Alzheimer's type completed brain structural magnetic resonance imaging (MRI), neuropsychological assessment, and a survey of instrumental activities of daily living (IADL). We utilized the partial least square (PLS) method to identify latent components that are predictive of IADL.

RESULTS

The result showed distinct brain components (gray matter density of cerebellar, medial temporal, subcortical, limbic, and default network regions) and cognitive-behavioral components (general cognitive abilities, processing speed, and executive function, episodic memory, and neuropsychiatric symptoms) were predictive of IADL. Subsequent path analysis showed that the effect of brain structural components on IADL was largely mediated by cognitive and behavioral components. When comparing hierarchical regression models, the brain structural measures minimally added the explanatory power of cognitive and behavioral measures on IADL.

CONCLUSION

Our finding suggests that cerebellar structure and orbitofrontal cortex, alongside with medial temporal lobe, play an important role in the maintenance of functional status in older adults with or without dementia. Moreover, the significance of brain structural volume affects real-life functional activities via disruptions in multiple cognitive and behavioral functions.

The ecological validity of the Uniform Data Set 3.0 neuropsychological battery in individuals with mild cognitive impairment and dementia

Objective: Ecological validity refers to the ability of neuropsychological measures to predict real world performance. Questions remain as to the ecological validity of commonly used measures, particularly regarding their relationships to global versus specific activities of daily living among those with neurodegenerative disease. We explored these issues through the lens of the Uniform Data Set 3.0 Neuropsychological battery (UDS3NB) in individuals with mild cognitive impairment and dementia. Method: UDS3NB and informant rated Functional Activities Questionnaire scales were evaluated from 2,253 individuals with mild cognitive impairment and dementia. Ordinal regression equations were used to explore the relationships of demographic and cognitive variables with overall and specific instrumental activities of daily living. Results: Delayed recall for visual and verbal material, and performance on trail making tests were consistent predictors of global and specific functions. Specific skills (i.e. naming or figure copy) showed differential relationships with specific activities, while phonemic fluency was not related to any particular activity. Conclusions: Measures in the UDS3NB predicted activities of daily living in individuals with MCI and dementia, providing initial support for the ecological validity of these tests. Specifically, measures that tap core deficits of Alzheimer's disease, such as delayed recall and sequencing/shifting, are consistent predictors of performance in daily tasks.

Apathy, Executive Function, and Emotion Recognition Are the Main Drivers of Functional Impairment in Behavioral Variant of Frontotemporal Dementia

Background: The cognitive and neuropsychiatric deficits present in patients with behavioral variant frontotemporal dementia (bvFTD) are associated with loss of functionality in the activities of daily living (ADLs). The main purpose of this study was to examine and explore the association between the cognitive and neuropsychiatric features that might prompt functional impairment of basic, instrumental, and advanced ADL domains in patients with bvFTD. Methods: A retrospective cross-sectional study was conducted with 27 patients with bvFTD in its early stage (<2 years of evolution) and 32 healthy control subjects. A neuropsychological assessment was carried out wherein measures of cognitive function and neuropsychiatric symptoms were obtained. The informant-report Technology-Activities of Daily Living Questionnaire was used to assess the percentage of functional impairment in the different ADL domains. To identify the best determinants, three separate multiple regression analyses were performed, considering each functional impairment as the dependent variable and executive function, emotion recognition, disinhibition, and apathy as independent variables. Results: For the basic ADLs, a model that explains 28.2% of the variability was found, in which the presence of apathy (β = 0.33, p = 0.02) and disinhibition (β = 0.29, p = 0.04) were significant factors. Concerning instrumental ADLs, the model produced accounted for 63.7% of the functional variability, with the presence of apathy (β = 0.71, p < 0.001), deficits in executive function (β = -0.36, p = 0.002), and lack of emotion recognition (β = 0.28, p = 0.017) as the main contributors. Finally, in terms of advanced ADLs, the model found explained 52.6% of the variance, wherein only the presence of apathy acted as a significant factor (β = 0.59, p < 0.001). Conclusions: The results of this study show the prominent and transverse effect of apathy in the loss of functionality throughout all the ADL domains. Apart from that, this is the first study that shows that the factors associated with loss of functionality differ according to the functional domain in patients with bvFTD in its early stage. Finally, no other study has analyzed the impact of the lack of emotion recognition in the functionality of ADLs. These results could guide the planning of tailored interventions that might enhance everyday activities and the improvement of quality of life.

How does carer management style influence the performance of activities of daily living in people with dementia?

INTRODUCTION

People with Dementia (PwD)'s performance of activities of daily living (ADLs) has been associated with apathy, cognitive deficits, carers' depression and burden. However, it is not known if the carers' management style affects ADL performance, particularly alongside PwD's cognitive deficits and apathy. Thus, the aim of this study was to explore the contribution of intrinsic (cognition, apathy) and extrinsic (carer management styles) dementia factors to ADL performance.

METHODS

PwD (n = 143) were assessed on global cognition (ACE-III); apathy (CBI-R); ADLs (Disability Assessment for Dementia-DAD). Carers' (n = 143) criticism, encouragement and active-management styles were assessed with the Dementia Management Strategy Scale (DMSS). Multiple linear regression analysis investigated contributions of carer styles, cognition, apathy (independent variables) on ADLs (dependent variable).

RESULTS

The best model explaining the variance of the DAD scores included cognition (β = 0.413, t₍₁₄₂₎  = 4.463, p = 0.001), apathy (β = -0.365, t₍₁₄₂₎  = -5.556, p = 0.001), carer criticism (β = -0.326, t₍₁₄₂₎  = -2.479, p = 0.014) and carer encouragement styles (β = 0.402, t₍₁₄₂₎  = 2.941, p = 0.004) accounting for 40% of the variance of the DAD scores.

CONCLUSIONS

This novel study demonstrated that PwD's level of apathy and the carer's use of criticism negatively affected ADL performance while PwD's cognitive abilities and carer encouragement style improved ADL performance. These findings have critical implications for the development of novel multi-component non-pharmacological interventions to maintain function and delay disease progression in dementia, as well as direct relevance to current carers and families.

Impact of the COVID-19 pandemic on older adults mental health services: A mixed methods study

OBJECTIVES

The COVID-19 pandemic has had a significant impact on older adults mental health care. Our study aimed to explore staff perspectives on key challenges and innovations in order to help inform the delivery of older adults mental health care in subsequent waves of the pandemic.

METHODS

A mixed methods online questionnaire developed by National Institute for Health Research Mental Health Policy Research Unit was used to gather staff perspectives on their challenges at work, problems faced by service users and their carers, and sources of help and support. Descriptive statistics were used for quantitative analysis and descriptive content analysis for qualitative analysis.

RESULTS

158 participants, working in either community or inpatient settings, and from a range of professional disciplines, were included. For inpatient staff, a significant challenge was infection control. In the community, staff identified a lack of access to physical and social care as well as reduced contact with friends and families as being challenges for patients. Remote working was seen as a positive innovation along with COVID-19 related guidance from various sources and peer support.

CONCLUSION

Our study, with a focus on staff and patient well-being, helps to inform service development for future waves of the pandemic. We discuss measures to improve infection control in inpatient settings, the role of voluntary organisations in supporting socially isolated community patients, the need for better integration of physical and mental health services at an organisational level, and the importance of training staff to support patients and their families with end of life planning.

Neuromodulation in the Treatment of Alzheimer's Disease: Current and Emerging Approaches

Neuromodulation as a treatment strategy for psychiatric and neurological diseases has grown in popularity in recent years, with the approval of repetitive transcranial magnetic stimulation (rTMS) for the treatment of depression being one such example. These approaches offer new hope in the treatment of diseases that have proven largely intractable to traditional pharmacological approaches. For this reason, neuromodulation is increasingly being explored for the treatment of Alzheimer's disease. However, such approaches have variable, and, in many cases, very limited evidence for safety and efficacy, with most human evidence obtained in small clinical trials. Here we review work in animal models and humans with Alzheimer's disease exploring emerging neuromodulation modalities. Approaches reviewed include deep brain stimulation, transcranial magnetic stimulation, transcranial electrical stimulation, ultrasound stimulation, photobiomodulation, and visual or auditory stimulation. In doing so, we clarify the current evidence for these approaches in treating Alzheimer's disease and identify specific areas where additional work is needed to facilitate their clinical translation.

Physical Activity and its Influencing Factors in Community-Dwelling Older Adults With Dementia: A Path Analysis

Dementia is prevalent in worldwide, and increases the care burden and potential costs. Physical activity (PA) has been increasingly shown to be beneficial for them. This was a cross-sectional observational study aiming to investigate the status of PA among community-dwelling older adults with dementia in Beijing or Hangzhou, China, and verify the relationships between neuropsychiatric symptoms, activities of daily living (ADL), caregivers' fear of patients' falling and their PA using a path analysis approach. The level of PA among 216 included people with dementia was low. PA was related to the neuropsychiatric symptoms, with ADL and caregivers' fear of patients' falling have mediation roles. The findings indicated that person-centered strategies related to the management of these symptoms might be helpful to improve ADL, relieve caregivers' concerns about them falling and consequently foster positive participation in PA.

Cellular senescence as a driver of cognitive decline triggered by chronic unpredictable stress

When an individual is under stress, the undesired effect on the brain often exceeds expectations. Additionally, when stress persists for a long time, it can trigger serious health problems, particularly depression. Recent studies have revealed that depressed patients have a higher rate of brain aging than healthy subjects and that depression increases dementia risk later in life. However, it remains unknown which factors are involved in brain aging triggered by chronic stress. The most critical change during brain aging is the decline in cognitive function. In addition, cellular senescence is a stable state of cell cycle arrest that occurs because of damage and/or stress and is considered a sign of aging. We used the chronic unpredictable stress (CUS) model to mimic stressful life situations and found that, compared with nonstressed control mice, CUS-treated C57BL/6 mice exhibited depression-like behaviors and cognitive decline. Additionally, the protein expression of the senescence marker p16^INK4a was increased in the hippocampus, and senescence-associated β-galactosidase (SA-β-gal)-positive cells were found in the hippocampal dentate gyrus (DG) in CUS-treated mice. Furthermore, the levels of SA-β-gal or p16^INK4a were strongly correlated with the severity of memory impairment in CUS-treated mice, whereas clearing senescent cells using the pharmacological senolytic cocktail dasatinib plus quercetin (D + Q) alleviated CUS-induced cognitive deficits, suggesting that targeting senescent cells may be a promising candidate approach to study chronic stress-induced cognitive decline. Our findings open new avenues for stress-related research and provide new insight into the association of chronic stress-induced cellular senescence with cognitive deficits.

Quantitative Assessment of Resting-State for Mild Cognitive Impairment Detection: A Functional Near-Infrared Spectroscopy and Deep Learning Approach

BACKGROUND

Mild cognitive impairment (MCI) is considered a prodromal stage of Alzheimer's disease. Early diagnosis of MCI can allow for treatment to improve cognitive function and reduce modifiable risk factors.

OBJECTIVE

This study aims to investigate the feasibility of individual MCI detection from healthy control (HC) using a minimum duration of resting-state functional near-infrared spectroscopy (fNIRS) signals.

METHODS

In this study, nine different measurement durations (i.e., 30, 60, 90, 120, 150, 180, 210, 240, and 270 s) were evaluated for MCI detection via the graph theory analysis and traditional machine learning approach, such as linear discriminant analysis, support vector machine, and K-nearest neighbor algorithms. Moreover, feature representation- and classification-based transfer learning (TL) methods were applied to identify MCI from HC through the input of connectivity maps with 30 and 90 s duration.

RESULTS

There was no significant difference among the nine various time windows in the machine learning and graph theory analysis. The feature representation-based TL showed improved accuracy in both 30 and 90 s cases (i.e., 30 s: 81.27% and 90 s: 76.73%). Notably, the classification-based TL method achieved the highest accuracy of 95.81% using the pre-trained convolutional neural network (CNN) model with the 30 s interval functional connectivity map input.

CONCLUSION

The results indicate that a 30 s measurement of the resting-state with fNIRS could be used to detect MCI. Moreover, the combination of neuroimaging (e.g., functional connectivity maps) and deep learning methods (e.g., CNN and TL) can be considered as novel biomarkers for clinical computer-assisted MCI diagnosis.

Association Between Early Psychotic Symptoms and Alzheimer's Disease Prognosis in a Community-Based Cohort

BACKGROUND

Psychotic symptoms are an important and increasingly recognized aspect of Alzheimer's disease (AD). They have been shown to contribute to faster disease progression in clinic-based, demographically homogenous samples with high educational attainment.

OBJECTIVE

We studied the association between baseline psychotic symptoms and disease progression among individuals with incident AD or 'at risk' of developing AD, from a demographically heterogenous, community-based cohort with minimal educational attainment.

METHODS

212 participants received the Columbia University Scale of Psychopathology in Alzheimer's Disease scale. Participants had psychotic symptoms with any of: visual illusions, delusions, hallucinations, or agitation/aggression. Disease progression was measured yearly and defined by meeting cognitive (≤10 on the Folstein MMSE) or functional endpoints (≥10 on the Blessed Dementia Rating Scale or ≥4 on the Dependence Scale).

RESULTS

The mean age was 85 years old. The cohort was 78.3% female, 75.9% Hispanic, and had a mean 6.96 years of education. Within the follow-up period (mean: 3.69 years), 24 met the cognitive endpoint, 59 met the functional endpoint, and 132 met the cutoff for dependence. The presence of at least one psychotic symptom was initially associated with an increased risk of reaching the functional endpoint (HR 3.12, 95% CI 1.67-5.86, p < 0.001) and the endpoint of dependence (HR = 1.498, 95% CI 1.05-2.13, p = 0.03). However, these associations were attenuated and non-significant when adjusted for baseline functional status. Psychotic symptoms were not associated with the cognitive endpoint.

CONCLUSION

Psychotic symptoms may predict functional decline in patients of non-Caucasian ethnicity and with lower educational attainment.

A complexidade da tarefa afeta negativamente o equilíbrio e a mobilidade de idosos saudáveis

Resumo Objetivo Analisar o impacto da complexidade da tarefa sobre mobilidade e equilíbrio de idosos saudáveis. Métodos Noventa idosos foram incluídos neste estudo. Os participantes foram submetidos a tarefas que simularam problemas comuns ao envelhecimento, como baixa acuidade visual, alterações na base de apoio e dificuldades em realizar atividades simultâneas. Para avaliação da mobilidade utilizou-se o teste Timed Get Up and Go associado a atividades de dupla-tarefa cognitiva e motora. Para o equilíbrio utilizou-se uma plataforma de força avaliada em diferentes bases de apoio e informações visuais. Testes cognitivos foram aplicados com objetivo de caracterizar a amostra e analisar a associação entre as variáveis motoras e cognitivas. Na análise estatística utilizou-se o teste de Friedman para verificar o efeito da complexidade da tarefa nos idosos e o coeficiente de correlação de Spearman para verificar a associação entre as variáveis motoras e cognitivas. O nível de significância foi estipulado em 5%. Resultados A complexidade da atividade interferiu na mobilidade dos participantes, exigindo um maior número de passos e tempo para realizar a tarefa (p=0,001). De maneira semelhante, uma base de apoio diminuída e informações visuais restritas causaram uma maior insegurança nos participantes frente às reações de equilíbrio (p=0,001). Testes de correlação apontaram associações significativas entre funções executivas e tarefas motoras complexas (p<0,05). Conclusão Idosos saudáveis apresentam instabilidade motora quando submetidos a tarefas complexas, potencializando as alterações provenientes do envelhecimento. A associação entre as variáveis cognitivas e motoras sugere a necessidade de assistência multiprofissional para preparar os idosos no enfrentamento de desafios diários.

GERO Cohort Protocol, Chile, 2017-2022: Community-based Cohort of Functional Decline in Subjective Cognitive Complaint elderly

BACKGROUND

With the global population aging and life expectancy increasing, dementia has turned a priority in the health care system. In Chile, dementia is one of the most important causes of disability in the elderly and the most rapidly growing cause of death in the last 20 years. Cognitive complaint is considered a predictor for cognitive and functional decline, incident mild cognitive impairment, and incident dementia. The GERO cohort is the Chilean core clinical project of the Geroscience Center for Brain Health and Metabolism (GERO). The objective of the GERO cohort is to analyze the rate of functional decline and progression to clinical dementia and their associated risk factors in a community-dwelling elderly with subjective cognitive complaint, through a population-based study. We also aim to undertake clinical research on brain ageing and dementia disorders, to create data and biobanks with the appropriate infrastructure to conduct other studies and facilitate to the national and international scientific community access to the data and samples for research.

METHODS

The GERO cohort aims the recruitment of 300 elderly subjects (> 70 years) from Santiago (Chile), following them up for at least 3 years. Eligible people are adults not diagnosed with dementia with subjective cognitive complaint, which are reported either by the participant, a proxy or both. Participants are identified through a household census. The protocol for evaluation is based on a multidimensional approach including socio-demographic, biomedical, psychosocial, neuropsychological, neuropsychiatric and motor assessments. Neuroimaging, blood and stool samples are also obtained. This multidimensional evaluation is carried out in a baseline and 2 follow-ups assessments, at 18 and 36 months. In addition, in months 6, 12, 24, and 30, a telephone interview is performed in order to keep contact with the participants and to assess general well-being.

DISCUSSION

Our work will allow us to determine multidimensional risks factors associated with functional decline and conversion to dementia in elderly with subjective cognitive complain. The aim of our GERO group is to establish the capacity to foster cutting edge and multidisciplinary research on aging in Chile including basic and clinical research.

TRIAL REGISTRATION

NCT04265482 in ClinicalTrials.gov. Registration Date: February 11, 2020. Retrospectively Registered.

Association between Daily Activities and Behavioral and Psychological Symptoms of Dementia in Community-Dwelling Older Adults with Memory Complaints by Their Families

It is important and useful to consider information provided by family members about individuals with memory complaints' instrumental activities of daily living (IADL). The purpose of this study was to clarify the characteristics and relevance of individuals with memory complaints' IADL and behavioral and psychological symptoms of dementia (BPSD) assessed from the perspective of the family members using the Process Analysis of Daily Activity for Dementia and short version Dementia Behavior Disturbance scale. A self-administered questionnaire was sent to 2000 randomly selected members of Consumer's Co-operative Kagoshima, and 621 responded. Of the returned responses, there were 159 participants who answered about individuals with memory complaints. The stepwise multiple regression analysis was used to examine the association between IADL and BPSD. The result showed that many IADL of the individuals with memory complaints were associated with BPSD of apathy, nocturnal wakefulness, and unwarranted accusations, adjusted for age, gender, and the observation list for early signs of dementia. In addition, each IADL was associated with BPSD of apathy, nocturnal wakefulness, and dresses inappropriately. Modifying lifestyle early on when families recognize these changes may help maintain and improve the long-term quality of life of the individuals with memory complaints and their family.

Insula and Amygdala Atrophy Are Associated With Functional Impairment in Subjects With Presbycusis

Hearing loss is an important risk factor for dementia. However, the mechanisms that relate these disorders are still unknown. As a proxy of this relationship, we studied the structural brain changes associated with functional impairment in activities of daily living in subjects with age related hearing loss, or presbycusis. One hundred eleven independent, non-demented subjects older than 65 years recruited in the ANDES cohort were evaluated using a combined approach including (i) audiological tests: hearing thresholds and cochlear function measured by pure tone averages and the distortion product otoacoustic emissions respectively; (ii) behavioral variables: cognitive, neuropsychiatric, and functional impairment in activities of daily living measured by validated questionnaires; and (iii) structural brain imaging—assessed by magnetic resonance imaging at 3 Tesla. The mean age of the recruited subjects (69 females) was 73.95 ± 5.47 years (mean ± SD) with an average educational level of 9.44 ± 4.2 years of schooling. According to the audiometric hearing thresholds and presence of otoacoustic emissions, we studied three groups: controls with normal hearing (n = 36), presbycusis with preserved cochlear function (n = 33), and presbycusis with cochlear dysfunction (n = 38). We found a significant association (R²_D = 0.17) between the number of detected otoacoustic emissions and apathy symptoms. The presbycusis with cochlear dysfunction group had worse performance than controls in global cognition, language and executive functions, and severe apathy symptoms than the other groups. The neuropsychiatric symptoms and language deficits were the main determinants of functional impairment in both groups of subjects with presbycusis. Atrophy of insula, amygdala, and other temporal areas were related with functional impairment, apathy, and language deficits in the presbycusis with cochlear dysfunction group. We conclude that (i) the neuropsychiatric symptoms had a major effect on functional loss in subjects with presbycusis, (ii) cochlear dysfunction is relevant for the association between hearing loss and behavioral impairment, and (iii) atrophy of the insula and amygdala among other temporal areas are related with hearing loss and behavioral impairment.

Association Between Neuropsychiatric Symptoms and Functional Change in Older Non-Demented Adults: Mayo Clinic Study of Aging

We examined the associations between baseline neuropsychiatric symptoms (NPS) and longitudinal changes in functional performance among 5,394 non-demented individuals aged ≥50 years (2,729 males; median age 74.2 years; 4,716 cognitively unimpaired, 678 mild cognitive impairment). After adjusting for age, sex, education, and medical comorbidities, NPS assessed by the Neuropsychiatric Inventory Questionnaire, clinical depression (Beck Depression Inventory score ≥13) and anxiety (Beck Anxiety Inventory score ≥10) were significantly associated with an increase in the Functional Activities Questionnaire score, indicating functional decline over time. This association may vary depending on the degree of cognitive impairment at baseline.

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.