APOE ε4 genotype-dependent cerebrospinal fluid proteomic signatures in Alzheimer's disease

Background

Aggregation of amyloid β into plaques in the brain is one of the earliest pathological events in Alzheimer’s disease (AD). The exact pathophysiology leading to dementia is still uncertain, but the apolipoprotein E (APOE) ε4 genotype plays a major role. We aimed to identify the molecular pathways associated with amyloid β aggregation using cerebrospinal fluid (CSF) proteomics and to study the potential modifying effects of APOE ε4 genotype.

Methods

We tested 243 proteins and protein fragments in CSF comparing 193 subjects with AD across the cognitive spectrum (65% APOE ε4 carriers, average age 75 ± 7 years) against 60 controls with normal CSF amyloid β, normal cognition, and no APOE ε4 allele (average age 75 ± 6 years).

Results

One hundred twenty-nine proteins (53%) were associated with aggregated amyloid β. APOE ε4 carriers with AD showed altered concentrations of proteins involved in the complement pathway and glycolysis when cognition was normal and lower concentrations of proteins involved in synapse structure and function when cognitive impairment was moderately severe. APOE ε4 non-carriers with AD showed lower expression of proteins involved in synapse structure and function when cognition was normal and lower concentrations of proteins that were associated with complement and other inflammatory processes when cognitive impairment was mild. Repeating analyses for 114 proteins that were available in an independent EMIF-AD MBD dataset (n = 275) showed that 80% of the proteins showed group differences in a similar direction, but overall, 28% effects reached statistical significance (ranging between 6 and 87% depending on the disease stage and genotype), suggesting variable reproducibility.

Conclusions

These results imply that AD pathophysiology depends on APOE genotype and that treatment for AD may need to be tailored according to APOE genotype and severity of the cognitive impairment.

Recommendations for the Nonpharmacological Treatment of Apathy in Brain Disorders

Apathy is a common neuropsychiatric syndrome observed across many neurocognitive and psychiatric disorders. Although there are currently no definitive standard therapies for the treatment of apathy, nonpharmacological treatment (NPT) is often considered to be at the forefront of clinical management. However, guidelines on how to select, prescribe, and administer NPT in clinical practice are lacking. Furthermore, although new Information and Communication Technologies (ICT) are beginning to be employed in NPT, their role is still unclear. The objective of the present work is to provide recommendations for the use of NPT for apathy, and to discuss the role of ICT in this domain, based on opinions gathered from experts in the field. The expert panel included 20 researchers and healthcare professionals working on brain disorders and apathy. Following a standard Delphi methodology, experts answered questions via several rounds of web-surveys, and then discussed the results in a plenary meeting. The experts suggested that NPT are useful to consider as therapy for people presenting with different neurocognitive and psychiatric diseases at all stages, with evidence of apathy across domains. The presence of a therapist and/or a caregiver is important in delivering NPT effectively, but parts of the treatment may be performed by the patient alone. NPT can be delivered both in clinical settings and at home. However, while remote treatment delivery may be cost and time-effective, it should be considered with caution, and tailored based on the patient's cognitive and physical profile and living conditions.

The quality of the relationship perceived by spouses of people with young-onset dementia

BACKGROUND

Young-onset dementia (YOD) has a profound impact on spouses. However, little is known on how the quality of the relationship changes over time in YOD. This study aims to determine how the quality of the relationship changes over time and identify predictors of this change.

METHODS

This study used data from the NEEDs in Young onset Dementia (NeedYD) study. The primary outcome measure was the quality of the relationship perceived by spouses measured throughout 24 months. Baseline characteristics of persons with YOD and spouses were also measured to assess their predictive value.

RESULTS

Totally, 178 dyads were included. The perceived quality of the relationship deteriorated over time. A longer symptom duration, a diagnosis of frontotemporal dementia, lower levels of awareness of deficits, lower levels of initiative toward daily living activities, and higher levels of apathy, hyperactivity, depression, and anxiety in the person with YOD were associated with a lower perceived quality of the relationship by spouses. A coping style characterized by palliative and passive reacting patterns and higher levels of neuroticism in spouses was also associated with a lower quality of the relationship.

CONCLUSION

The quality of the relationship as perceived by spouses deteriorated over time and was influenced by characteristics of the person with YOD as well as their spouse. Helping spouses to come to terms with factors that threaten their sense of couplehood might help them to develop a more positive attitude toward their spousal relationship and improve the quality of the relationship and care.

Interventions to enhance access to and utilization of formal community care services for home dwelling persons with dementia and their informal carers. A scoping review

Objectives: Home dwelling people with dementia and their informal carers often do not receive the formal care services they need. This study examined and mapped the research regarding interventions to improve access and use of formal community care services.Method: This is a scoping review with searches in PubMed, CINAHL, PsychINFO, Medline, Cochrane Database of Systematic Reviews, Social Science Citation index and searches of grey literature in international and national databases. Studies were categorized according to the measure used to enhance access or use.Results: From international databases, 2833 studies were retrieved, 11 were included. Five studies were included from other sources. In total, 16 studies published between 1989 and 2018 were examined; seven randomized controlled trials, six pretest-posttest studies and three non-randomized controlled studies. Sample sizes varied from 29 to 2682 participants, follow-up from four weeks to four years. Five types of interventions were identified: Case management, monetary support, referral enhancing, awareness & information focused and inpatient focused. Only two studies had access or use of community services as the primary outcome. Fourteen studies, representing all five types of interventions, had positive effects on one or more relevant outcomes. Two interventions had no effect on relevant outcomes.Conclusion: The included studies varied widely regarding design, type of intervention and outcomes. Based on this, the evidence base for interventions to enhance access to and use of formal community services is judged to be limited. The most studied type of intervention was case management. More research is recommended in this field.

Do caregiver profiles predict the use of dementia care services? Findings from the Actifcare study

Objectives: Previously developed dementia caregiver profiles defined by caregiver age and burden, have been associated with caregiver quality of life, depression and perseverance time. The current aim was to investigate whether these caregiver profiles could predict subsequent service use. In addition, non-personal (e.g. meals on wheels) and supportive services (e.g. Alzheimer café) in early dementia were investigated as predictors.Methods: A total of 451 dyads of people with dementia and their informal caregivers from eight European countries were followed for one year. People were included if they did not use formal (personal) care but were expected to do so within 1 year. Logistic regression analyses were used with four clusters of service use as dependent variables (home social care, home personal care, day care and admission). The independent variables were caregiver profiles, and non-personal and supportive services at baseline.Results: Caregiver profiles were significant predictors of service use; those experiencing high strain were more likely to use formal care. The use of low-intensity, less intrusive services at baseline significantly predicted the use of home personal care and admission at follow-up. The use of day care at follow-up was predicted by the baseline use of supportive services.Conclusion: Caregiver profiles are valuable predictors for service use: this knowledge can aid professionals in ensuring optimal access to services, which is important for maintaining independence at home. In addition, the use of supportive and less intrusive, non-personal services in the early stages of dementia is to be advised.

Long-term dementia risk prediction by the LIBRA score: A 30-year follow-up of the CAIDE study

OBJECTIVE

As no causal treatment for dementia is available yet, the focus of dementia research is slowly shifting towards prevention strategies. Therefore, this study aimed to examine the predictive accuracy of the "LIfestyle for BRAin Health" (LIBRA) score, a weighted compound score of 12 modifiable risk and protective factors, for dementia and mild cognitive impairment (MCI) in midlife and late-life, and in individuals with high or low genetic risk based on presence of the apolipoprotein (APOE) ε4 allele.

METHODS

The LIBRA score was calculated for participants from the Finnish Cardiovascular Risk Factors, Aging and Dementia (CAIDE) population-based study examined in midlife (n = 1024) and twice in late-life (n = 604) up to 30 years later. Diagnoses of MCI and dementia were made according to established criteria. Cox proportional hazards models were used to assess the association between LIBRA and risk of dementia and MCI in models adjusted for sex and education (age as timescale).

RESULTS

Higher midlife LIBRA scores were related to higher risk of dementia (hazard ratio [HR] = 1.27; 95% confidence interval [CI], 1.13-1.43) and MCI (unadjusted model: HR = 1.12; 95% CI, 1.03-1.22) up to 30 years later. Higher late-life LIBRA scores were related to higher risk of MCI (HR = 1.11; 95% CI, 1.00-1.25), but not dementia (HR = 1.02; 95% CI, 0.84-1.24). Higher late-life LIBRA scores were related to higher dementia risk among apolipoprotein E (APOE) ε4 non-carriers.

CONCLUSIONS

Findings emphasize the importance of modifiable risk and protective factors for dementia prevention.

A comparison of self and proxy quality of life ratings for people with dementia and their carers: a European prospective cohort study

Objectives: To identify correlates of self-rated and proxy-rated quality of life (QoL) in people with dementia on (i) a dementia-specific and (ii) a capability-wellbeing QoL measure at baseline and 12-month follow-up, and to consider such factors in the context of QoL intervention development.Method: Prospective clinical and demographic data were collected from 451 community-dwelling dyads (mild-moderate dementia) across eight European countries. QoL was measured using the QOL-AD and the ICECAP-O. Multivariate modelling identified correlates of self- and proxy-rated QoL at baseline and at 12-month follow-up.Results: Carer's proxy-ratings of QoL were significantly lower than self-ratings at all time-points for both measures. Proxy-ratings declined over time, but self-ratings remained stable. Baseline predictors of greater self-rated QoL were education, and greater functional ability and relationship quality. Greater proxy-rated QoL was associated with education and greater functional ability, relationship quality, carer social support and carer QoL, lower carer anxiety/depression and less severe neuropsychiatric symptoms in people with dementia. At follow-up, greater self-rated QoL was predicted by greater functional ability, relationship quality, carer social support and having a spousal carer. Greater proxy-rated QoL at follow-up was associated with the same factors as at baseline; however, the dyad living together was an additional predictive factor.Conclusion: Both proxy-ratings and self-ratings of QoL should be interpreted with caution and in the context of each individual caregiving relationship. Different functional, psychosocial, relational and contextual factors influence self- and proxy-ratings, and both sets of factors should be considered in the context of QoL intervention development for the dyad.

Dickkopf-1 Overexpression in vitro Nominates Candidate Blood Biomarkers Relating to Alzheimer's Disease Pathology

BACKGROUND

Previous studies suggest that Dickkopf-1 (DKK1), an inhibitor of Wnt signaling, plays a role in amyloid-induced toxicity and hence Alzheimer's disease (AD). However, the effect of DKK1 expression on protein expression, and whether such proteins are altered in disease, is unknown.

OBJECTIVE

We aim to test whether DKK1 induced protein signature obtained in vitro were associated with markers of AD pathology as used in the amyloid/tau/neurodegeneration (ATN) framework as well as with clinical outcomes.

METHODS

We first overexpressed DKK1 in HEK293A cells and quantified 1,128 proteins in cell lysates using aptamer capture arrays (SomaScan) to obtain a protein signature induced by DKK1. We then used the same assay to measure the DKK1-signature proteins in human plasma in two large cohorts, EMIF (n = 785) and ANM (n = 677).

RESULTS

We identified a 100-protein signature induced by DKK1 in vitro. Subsets of proteins, along with age and apolipoprotein E ɛ4 genotype distinguished amyloid pathology (A + T-N-, A+T+N-, A+T-N+, and A+T+N+) from no AD pathology (A-T-N-) with an area under the curve of 0.72, 0.81, 0.88, and 0.85, respectively. Furthermore, we found that some signature proteins (e.g., Complement C3 and albumin) were associated with cognitive score and AD diagnosis in both cohorts.

CONCLUSIONS

Our results add further evidence for a role of DKK regulation of Wnt signaling in AD and suggest that DKK1 induced signature proteins obtained in vitro could reflect theATNframework as well as predict disease severity and progression in vivo.

Validation of Plasma Proteomic Biomarkers Relating to Brain Amyloid Burden in the EMIF-Alzheimer's Disease Multimodal Biomarker Discovery Cohort

We have previously investigated, discovered, and replicated plasma protein biomarkers for use to triage potential trials participants for PET or cerebrospinal fluid measures of Alzheimer's disease (AD) pathology. This study sought to undertake validation of these candidate plasma biomarkers in a large, multi-center sample collection. Targeted plasma analyses of 34 proteins with prior evidence for prediction of in vivo pathology were conducted in up to 1,000 samples from cognitively healthy elderly individuals, people with mild cognitive impairment, and in patients with AD-type dementia, selected from the EMIF-AD catalogue. Proteins were measured using Luminex xMAP, ELISA, and Meso Scale Discovery assays. Seven proteins replicated in their ability to predict in vivo amyloid pathology. These proteins form a biomarker panel that, along with age, could significantly discriminate between individuals with high and low amyloid pathology with an area under the curve of 0.74. The performance of this biomarker panel remained consistent when tested in apolipoprotein E ɛ4 non-carrier individuals only. This blood-based panel is biologically relevant, measurable using practical immunocapture arrays, and could significantly reduce the cost incurred to clinical trials through screen failure.

Is there equity in initial access to formal dementia care in Europe? The Andersen Model applied to the Actifcare cohort

OBJECTIVES

In the current study, the Anderson model is used to determine equitable access to dementia care in Europe. Predisposing, enabling, and need variables were investigated to find out whether there is equitable access to dementia-specific formal care services. Results can identify which specific factors should be a target to improve access.

METHODS

A total of 451 People with middle-stage dementia and their informal carers from eight European countries were included. At baseline, there was no use of formal care yet, but people were expected to start using formal care within the next year. Logistic regressions were carried out with one of four clusters of service use as dependent variables (home social care, home personal care, day care, admission). The independent variables (predisposing, enabling, and need variables) were added to the regression in blocks.

RESULTS

The most significant predictors for the different care clusters are disease severity, a higher sum of (un)met needs, hours spent on informal care, living alone, age, region of residence, and gender.

CONCLUSION

The Andersen model provided for this cohort the insight that (besides need factors) the predisposing variables region of residence, gender, and age do play a role in finding access to care. In addition, it showed us that the numbers of hours spent on informal care, living alone, needs, and disease severity are also important predictors within the model's framework. Health care professionals should pay attention to these predisposing factors to ensure that they do not become barriers for those in need for care.

A metabolite-based machine learning approach to diagnose Alzheimer-type dementia in blood: Results from the European Medical Information Framework for Alzheimer disease biomarker discovery cohort

Introduction

Machine learning (ML) may harbor the potential to capture the metabolic complexity in Alzheimer Disease (AD). Here we set out to test the performance of metabolites in blood to categorize AD when compared to CSF biomarkers.

Methods

This study analyzed samples from 242 cognitively normal (CN) people and 115 with AD-type dementia utilizing plasma metabolites (n = 883). Deep Learning (DL), Extreme Gradient Boosting (XGBoost) and Random Forest (RF) were used to differentiate AD from CN. These models were internally validated using Nested Cross Validation (NCV).

Results

On the test data, DL produced the AUC of 0.85 (0.80–0.89), XGBoost produced 0.88 (0.86–0.89) and RF produced 0.85 (0.83–0.87). By comparison, CSF measures of amyloid, p-tau and t-tau (together with age and gender) produced with XGBoost the AUC values of 0.78, 0.83 and 0.87, respectively.

Discussion

This study showed that plasma metabolites have the potential to match the AUC of well-established AD CSF biomarkers in a relatively small cohort. Further studies in independent cohorts are needed to validate whether this specific panel of blood metabolites can separate AD from controls, and how specific it is for AD as compared with other neurodegenerative disorders.

A validation study of the ICECAP-O in informal carers of people with dementia from eight European Countries

PURPOSE

The pressure on healthcare budgets remains high, partially due to the ageing population. Economic evaluation can be a helpful tool to inform resource allocation in publicly financed systems. Such evaluations frequently use health-related outcome measures. However, in areas such as care of older people, improving health outcomes is not necessarily the main focus of care interventions and broader outcome measures, including outcomes for those providing informal care, may be preferred when evaluating such interventions. This paper validates a recently introduced well-being measure, the ICECAP-O, in a population of informal carers for people with dementia from eight European countries.

METHODS

Convergent and discriminant validity tests were performed to validate the ICECAP-O using data obtained in a sample of 451 respondents from Germany, Ireland, Italy, the Netherlands, Norway, Portugal, Sweden and the UK. These respondents completed a number of standardized questionnaires within the framework of the Actifcare project.

RESULTS

The ICECAP-O performed well among informal carers, in terms of both convergent and discriminant validity. In the multivariate analysis, it was found to be significantly associated with the age of the person with dementia, EQ-5D-5L health problem index of the person with dementia, carer-patient relationship, care recipient CDR, carer LSNS Score, the PAI score, and Perseverance Time.

CONCLUSION

The ICECAP-O appears to be a valid measure of well-being in informal carers for people with dementia. The ICECAP-O may therefore be useful as an outcome measure in economic evaluations of interventions aimed at such informal carers, when these aim to improve well-being beyond health.

Biomarker-based prognosis for people with mild cognitive impairment (ABIDE): a modelling study

BACKGROUND

Biomarker-based risk predictions of dementia in people with mild cognitive impairment are highly relevant for care planning and to select patients for treatment when disease-modifying drugs become available. We aimed to establish robust prediction models of disease progression in people at risk of dementia.

METHODS

In this modelling study, we included people with mild cognitive impairment (MCI) from single-centre and multicentre cohorts in Europe and North America: the European Medical Information Framework for Alzheimer's Disease (EMIF-AD; n=883), Alzheimer's Disease Neuroimaging Initiative (ADNI; n=829), Amsterdam Dementia Cohort (ADC; n=666), and the Swedish BioFINDER study (n=233). Inclusion criteria were a baseline diagnosis of MCI, at least 6 months of follow-up, and availability of a baseline Mini-Mental State Examination (MMSE) and MRI or CSF biomarker assessment. The primary endpoint was clinical progression to any type of dementia. We evaluated performance of previously developed risk prediction models-a demographics model, a hippocampal volume model, and a CSF biomarkers model-by evaluating them across cohorts, incorporating different biomarker measurement methods, and determining prognostic performance with Harrell's C statistic. We then updated the models by re-estimating parameters with and without centre-specific effects and evaluated model calibration by comparing observed and expected survival. Finally, we constructed a model combining markers for amyloid deposition, tauopathy, and neurodegeneration (ATN), in accordance with the National Institute on Aging and Alzheimer's Association research framework.

FINDINGS

We included all 2611 individuals with MCI in the four cohorts, 1007 (39%) of whom progressed to dementia. The validated demographics model (Harrell's C 0·62, 95% CI 0·59-0·65), validated hippocampal volume model (0·67, 0·62-0·72), and updated CSF biomarkers model (0·72, 0·68-0·74) had adequate prognostic performance across cohorts and were well calibrated. The newly constructed ATN model had the highest performance (0·74, 0·71-0·76).

INTERPRETATION

We generated risk models that are robust across cohorts, which adds to their potential clinical applicability. The models could aid clinicians in the interpretation of CSF biomarker and hippocampal volume results in individuals with MCI, and help research and clinical settings to prepare for a future of precision medicine in Alzheimer's disease. Future research should focus on the clinical utility of the models, particularly if their use affects participants' understanding, emotional wellbeing, and behaviour.

FUNDING

ZonMW-Memorabel.

Discovery and validation of plasma proteomic biomarkers relating to brain amyloid burden by SOMAscan assay

Introduction

Plasma proteins have been widely studied as candidate biomarkers to predict brain amyloid deposition to increase recruitment efficiency in secondary prevention clinical trials for Alzheimer's disease. Most such biomarker studies are targeted to specific proteins or are biased toward high abundant proteins.

Methods

4001 plasma proteins were measured in two groups of participants (discovery group = 516, replication group = 365) selected from the European Medical Information Framework for Alzheimer's disease Multimodal Biomarker Discovery study, all of whom had measures of amyloid.

Results

A panel of proteins (n = 44), along with age and apolipoprotein E (APOE) ε4, predicted brain amyloid deposition with good performance in both the discovery group (area under the curve = 0.78) and the replication group (area under the curve = 0.68). Furthermore, a causal relationship between amyloid and tau was confirmed by Mendelian randomization.

Discussion

The results suggest that high-dimensional plasma protein testing could be a useful and reproducible approach for measuring brain amyloid deposition.

Optimizing access to and use of formal dementia care: Qualitative findings from the European Actifcare study

This paper reports on qualitative data from the Actifcare study investigating experiences, attitudes, barriers and facilitators concerning access to and use of formal care. A total of 85 semi-structured in-depth interviews were conducted in eight European countries. Results were analysed with a deductive content analysis, first within country and then integrated in a cross-national analysis. Overall, analysis of the in-depth interviews revealed two major themes with five subcategories. The results can be summarised in an optimal pathway for access to dementia care. This pathway includes fixed factors such as disease-related factors and system-related factors. In addition there are personal factors that are subject to change such as attitudes towards care. An important finding consisted of the necessity of having sufficient information about the disease and available care and having a key contact person to guide you through the process of finding suitable care while monitoring your needs. In addition, it is important to involve your social network as they can take on care-giving tasks. It is helpful to have a diagnosis (in most countries). Concerning decision-making, the person closest to the person with dementia is in the majority of cases the one who makes the ultimate decision to access and use services and he/she should therefore be supported in this process. These results provide insight into the factors that influence the pathway to formal care use and help professionals to enhance access to formal dementia care by focusing on factors that can be modified.

Vascular risk factors are associated with longitudinal changes in cerebrospinal fluid tau markers and cognition in preclinical Alzheimer's disease

INTRODUCTION

Vascular factors increase the risk of Alzheimer's disease (AD). We investigated the associations between such factors, longitudinal AD cerebrospinal fluid biomarkers, and cognition.

METHODS

433 cognitively normal participants were classified into four biomarker groups using their baseline amyloid (A+/-) and tau status (T+/-). 184 participants had undergone serial cerebrospinal fluid collection. Frequencies of risk factors and the Framingham Risk Score (FRS) were compared, and we tested the influence of risk factors on change in biomarker concentrations and cognition.

RESULTS

The absence of obesity, presence of hypertension, and a high FRS were associated with an increase in tau levels, particularly in A+T+ individuals. Risk factors were not associated with amyloid. Depression was associated with higher cognitive scores, whereas high FRS was associated with lower scores and a faster decline.

DISCUSSION

Our results demonstrate that vascular risk factors may enhance neurodegeneration but not amyloid accumulation in preclinical AD.

Dementia awareness and risk perception in middle-aged and older individuals: baseline results of the MijnBreincoach survey on the association between lifestyle and brain health

BACKGROUND

The total number of people with dementia is increasing worldwide, due to our aging society. Without a disease-modifying drug available, risk reduction strategies are to date the only promising way to reduce dementia incidence in the future. Substantial evidence exists that lifestyle factors contribute to the risk of dementia, such as physical exercise, mental activity and (non-)smoking. Still, most people seem unaware of a relationship between lifestyle and brain health. This paper investigates dementia literacy and knowledge of modifiable risk and protective factors of dementia in a Dutch population-based sample.

METHODS

An online-survey was carried out among 590 community-dwelling people between 40 and 75 years old in the Province of Limburg, the Netherlands. The total group comprises both of a provincial sample (n = 381) and a sample of three specific districts within the province (n = 209). Dementia awareness and knowledge about 12 risk and protective factors was assessed with items derived from the British Social Attitudes (BSA) survey, supplemented with custom items developed by the research team.

RESULTS

The majority of participants (56%) were unaware of a relationship between lifestyle and dementia risk. Most individuals identified low cognitive activity, physical inactivity and unhealthy diet as dementia risk factors. Particular gaps in knowledge existed with regard to major cardiovascular risk factors such as hypertension, hypercholesterolemia and coronary heart disease. Although the level of awareness varied by age and level of education, most people (70%) were eager to learn more about the topic of brain health, and indicated to be interested in using eHealth (54%) to measure or improve brain health.

CONCLUSIONS

Most people still are unaware of the relation between lifestyle and brain health, indicating the need for public health campaigns. Increasing awareness in the general population about the presence of modifiable dementia risk and protective factors is a crucial first step prior to implementation of preventative measures. Targeting specific subgroups, such as individuals with low socioeconomic status and low health literacy, is essential for the reach and effect of a prevention campaign. Outcome of this study was the rationale for an awareness campaign in The Netherlands, called "MijnBreincoach" ("MyBraincoach").

[Needs for Care and Service Use in Dementia: Baseline Assessment of Portuguese Participants in the Actifcare Cohort Study]

INTRODUCTION

People with dementia and their relatives should have timely access to formal care in the community. The EU-Actifcare project analysed access to and use of formal services, as related to unmet needs for care. We describe the cohort study implementation and baseline results in Portugal, with a focus on needs for care and service use assessments.

MATERIAL AND METHODS

Our convenience sample consisted of 66 dyads of community-dwelling people with mild to moderate dementia and no significant use of formal services, and their informal carers. Measures included the Camberwell Assessment of Need for the Elderly and Resources Utilization in Dementia.

RESULTS

People with dementia had unmet needs (mean 1.1; SD 1.7), mainly regarding company (23%), psychological distress (20%), and daily activities (14%). Family caregivers spent 150 minutes/day (median) providing support, and 44% had psychological distress unmet needs. Problems with access to or use of formal services, when present, were frequently due to attitudes or lack of knowledge of any or both members of the dyad.

DISCUSSION

The recruitment process was challenging, since the inclusion criteria were restrictive. Not claiming generalizability, we recruited a typical sample of Portuguese people with mild to moderate dementia and no significant formal community support. Levels and type of unmet needs found in some participants would call for formal support, were it not for problems regarding access or use.

CONCLUSION

There are difficulties regarding timely access and effective use of formal care in dementia, along with relevant unmet needs.

Relationship quality and sense of coherence in dementia: Results of a European cohort study

OBJECTIVE

Quality of life of people with dementia and their family carers is strongly influenced by interpersonal issues and personal resources. In this context, relationship quality (RQ) and sense of coherence (SOC) potentially protect and promote health. We aimed to identify what influences RQ in dyads of people with dementia and their carers and to examine differences in their perspectives.

METHODS

Cross-sectional data were used from the Actifcare cohort study of 451 community-dwelling people with dementia and their primary carers in eight European countries. Comprehensive assessments included the Positive Affect Index (RQ) and the Orientation to Life Questionnaire (SOC).

RESULTS

Regression analyses revealed that RQ as perceived by people with dementia was associated with carer education, stress, and spouse caregiving. RQ as perceived by carers was associated with carer stress, depression, being a spouse, social support, reported neuropsychiatric symptoms of dementia, and carer SOC. Neuropsychiatric symptoms and carer stress contributed to discrepancies in RQ ratings within the dyad. The only factor associated with both individual RQ ratings and discrepancies was carer stress (negative feelings subscore). No significant differences in the overall perception of RQ were evident between spouses and adult children carers, but RQ determinants differed between the two.

CONCLUSIONS

In this European sample, carer SOC was associated with carer-reported RQ. RQ determinants differed according to the perspective considered (person with dementia or carer) and carer subgroup. A deeper understanding of RQ and its determinants will help to tailor interventions that address these distinct perspectives and potentially improve dementia outcomes.

Cerebrospinal fluid biomarkers of neurodegeneration, synaptic integrity, and astroglial activation across the clinical Alzheimer's disease spectrum

INTRODUCTION

We investigated relations between amyloid-β (Aβ) status, apolipoprotein E (APOE) ε4, and cognition, with cerebrospinal fluid markers of neurogranin (Ng), neurofilament light (NFL), YKL-40, and total tau (T-tau).

METHODS

We included 770 individuals with normal cognition, mild cognitive impairment, and Alzheimer's disease (AD)-type dementia from the EMIF-AD Multimodal Biomarker Discovery study. We tested the association of Ng, NFL, YKL-40, and T-tau with Aβ status (Aβ- vs. Aβ+), clinical diagnosis APOE ε4 carriership, baseline cognition, and change in cognition.

RESULTS

Ng and T-tau distinguished between Aβ+ from Aβ- individuals in each clinical group, whereas NFL and YKL-40 were associated with Aβ+ in nondemented individuals only. APOE ε4 carriership did not influence NFL, Ng, and YKL-40 in Aβ+ individuals. NFL was the best predictor of cognitive decline in Aβ+ individuals across the cognitive spectrum.

DISCUSSION

Axonal degeneration, synaptic dysfunction, astroglial activation, and altered tau metabolism are involved already in preclinical AD. NFL may be a useful prognostic marker.

The MMSE should not be the sole indicator of fitness to drive in mild Alzheimer's dementia

Since Alzheimer’s disease may affect driving performance, patients with Alzheimer’s disease are assessed on fitness to drive. On-road driving assessments are widely used, and attempts have also been made to develop strategies to assess fitness to drive in a clinical setting. Preferably, a first indication of fitness to drive is obtained quickly after diagnosis using a single test such as the Mini-Mental State Examination (MMSE). The aim of this study is to investigate whether the MMSE can be used to predict whether patients with Alzheimer’s disease will pass or fail an on-road driving assessment. Patients with Alzheimer’s disease (n = 81) participated in a comprehensive fitness-to-drive assessment which included the MMSE as well as an on-road driving assessment [PLoS One 11(2):e0149566, 2016]. MMSE cutoffs were applied as suggested by Versijpt and colleagues [Acta Neurol Belg 117(4):811–819, 2017]. All patients with Alzheimer’s disease who scored below the lower cutoff (MMSE ≤ 19) failed the on-road driving assessment. However, a third of the patients with Alzheimer’s disease who scored above the upper cutoff (MMSE ≥ 25) failed the on-road driving assessment as well. We conclude that the MMSE alone has insufficient predictive value to correctly identify fitness to drive in patients with very mild-to-mild Alzheimer’s disease implicating the need for comprehensive assessments to determine fitness to drive in a clinical setting.

Lack of associations between modifiable risk factors and dementia in the very old: findings from the Cambridge City over-75s cohort study

OBJECTIVES

To investigate the association between modifiable risk and protective factors and severe cognitive impairment and dementia in the very old. Additionally, the present study tests the predictive validity of the 'LIfestyle for BRAin health' (LIBRA) score, an index developed to assess an individual's dementia prevention potential.

METHOD

Two hundred seventy-eight individuals aged 85 years or older from the Cambridge City over-75s cohort study were followed-up until death. Included risk and protective factors were: diabetes, heart disease, hypertension, depression, smoking, low-to-moderate alcohol use, high cognitive activity, and physical inactivity. Incident severe cognitive impairment was based on the Mini-Mental State Examination (score: 0-17) and incident dementia was based on either post-mortem consensus clinical diagnostic assessments or death certificate data. Logistic regressions were used to test whether individual risk and protective factors and the LIBRA score were associated with severe cognitive impairment or dementia after 18 years follow-up.

RESULTS

None of the risk and protective factors or the LIBRA score was significantly associated with increased risk of severe cognitive impairment or dementia. Sensitivity analyses using a larger sample, longer follow-up period, and stricter cut-offs for prevalent cognitive impairment showed similar results.

CONCLUSION

Associations between well-known midlife risk and protective factors and risk for severe cognitive impairment or dementia might not persist into very old age, in line with suggestions that targeting these factors through lifestyle interventions should start earlier in life.

Association Between Later Life Lifestyle Factors and Alzheimer's Disease Biomarkers in Non-Demented Individuals: A Longitudinal Descriptive Cohort Study

BACKGROUND

Lifestyle factors have been associated with the risk of dementia, but the association with Alzheimer's disease (AD) remains unclear.

OBJECTIVE

To examine the association between later life lifestyle factors and AD biomarkers (i.e., amyloid-β 1-42 (Aβ42) and tau in cerebrospinal fluid (CSF), and hippocampal volume) in individuals with subjective cognitive decline (SCD) and mild cognitive impairment (MCI). In addition, to examine the effect of later life lifestyle factors on developing AD-type dementia in individuals with MCI.

METHODS

We selected individuals with SCD (n = 111) and MCI (n = 353) from the DESCRIPA and Kuopio Longitudinal MCI studies. CSF Aβ42 and tau concentrations were assessed with ELISA assay and hippocampal volume with multi-atlas segmentation. Lifestyle was assessed by clinical interview at baseline for: social activity, physical activity, cognitive activity, smoking, alcohol consumption, and sleep. We performed logistic and Cox regression analyses adjusted for study site, age, gender, education, and diagnosis. Prediction for AD-type dementia was performed in individuals with MCI only.

RESULTS

Later life lifestyle factors were not associated with AD biomarkers or with conversion to AD-type dementia. AD biomarkers were strongly associated with conversion to AD-type dementia, but these relations were not modulated by lifestyle factors. Apolipoprotein E (APOE) genotype did not influence the results.

CONCLUSIONS

Later life lifestyle factors had no impact on key AD biomarkers in individuals with SCD and MCI or on conversion to AD-type dementia in MCI.