Target risk factors for dementia prevention: a systematic review and Delphi consensus study on the evidence from observational studies

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").

Effect of depressive disorder on cognitive decline

This study longitudinally investigates the effect of depressive disorder on psychiatric disorder in middle aged and aged population from the Korean Longitudinal Study of Aging. Data from the Korean Longitudinal Study of Aging (KLoSA) from 2006 to 2016 was assessed using longitudinal data analysis and 7515 research samples were included after excluding those with cognitive decline and missing information at baseline (2006). To analyze the association between depressive disorder on cognitive decline in middle aged and aged population, generalized estimating equation (GEE) model and chi-square test were used. The association between depressive symptom during a week and center for epidemiological studies depression (CESD) on cognitive decline was statistically significant, respectively with the following Odds ratio (OR) predicting decreased MMSE score: OR = 0.89 (p < .0001) for 5-7 days vs. less than a day and B = 0.91 (p < .0001) for depression (8-10) vs. healthy (zero). In terms of cognitive decline, depressive symptom was higher for 5-7 days (OR = 3.79, p < .0001) compared to less than a day. This study shows a statistically significant association between depressive disorder and cognitive decline in a Korean middle aged and aged population. These findings suggest the importance of managing depressive disorder for incident cognitive decline.

Analyzing Mortality Risk and Medical Burden among Patients with Traumatic Brain Injury and Subsequent Dementia

We used the National Health Insurance Research Database of Taiwan to determine whether patients with posttraumatic dementia (PTD) exhibit increased mortality and medical burden than those without it. Patients ≥20 years of age having head injury admission (per the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes 850–854, 959.01) between 2000 and 2012 were enrolled as traumatic brain injury (TBI) cohort. A PTD cohort (with ICD-9-CM codes 290, 294.1, 331.0) and a posttraumatic nondementia (PTN) cohort were established and compared in terms of age, sex, and comorbidities. We calculated adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) of all-cause mortality risk, number of hospital days, and frequency of medical visits in these cohorts. Patients with PTD had a higher mortality rate than did patients with TBI alone (rate per 1000 person-years: 12.00 vs. 6.32), with an aHR of 1.54 (95% CI: 1.32–1.80). Patients with PTD who were aged ≥65 years (aHR = 1.54, 95% CI: 1.31–1.80) or male (aHR = 1.78, 95% CI: 1.45–2.18) exhibited greatly increased risks of mortality. Furthermore, patients with PTD had 19.9 more hospital days and required medical visits 4.49 times more frequently compared with the PTN cohort. Taiwanese patients with PTD had increased mortality risk and medical burden compared with patients who had TBI only. Our findings provide crucial information for clinicians and the government to improve TBI and PTD outcomes.

A modified Delphi and cross-sectional survey to facilitate selection of optimal outcomes and measures for a systematic review on geriatrician-led care models

OBJECTIVE

The objective of this study was to identify relevant outcomes and measures to inform a systematic review (SR) on the comparative effectiveness of geriatrician-led care models.

STUDY DESIGN AND SETTING

In the modified Delphi to select outcomes for inclusion in the SR, knowledge users (KUs) from Ontario, Alberta, and Saskatchewan rated outcome importance using a Likert scale. A survey was then completed by geriatricians to determine optimal measures for selected outcomes. Findings were analyzed using frequencies, means, and standard deviations (SDs).

RESULTS

Thirty-three KUs (patients, caregivers, policymakers and geriatricians) rated 27 outcomes in round 1 of the modified Delphi. Top-rated outcomes included function (mean 6.85 ± SD 0.36), cognition (6.47 ± SD 0.72), and quality of life (6.38 ± SD 0.91). Twenty-three KUs participated in round 2 and rated 24 outcomes. Top-rated outcomes in round 2 were function (6.87 ± SD 0.34), quality of life (6.45 ± SD 1.10), and cognition (6.43 ± SD 0.73). The survey was completed by 22 geriatricians and the highest ranked measures were Activities of Daily Living (function), Mini-Mental State Examination (cognition), and the Medical Outcomes Study SF-36 (quality of life).

CONCLUSION

We identified the most relevant outcomes and measures for patients, caregivers, policymakers, and geriatricians, allowing us to tailor the SR to KU needs.

Sex-specific incident dementia in patients with central nervous system trauma

Introduction

Despite evidence that central nervous system (CNS) trauma, including traumatic brain injury and spinal cord injury, can cause sustained neurocognitive impairment, it remains unclear whether trauma-related variables are associated with incident dementia independently of other known risk factors.

Methods

All adults without dementia entering the health-care system with diagnoses of CNS trauma were examined for occurrence of dementia. All trauma-related variables were examined as predictors in sex-specific Cox regression models, controlling for other known risk factors.

Results

Over a median follow-up of 52 months, 32,834 of 712,708 patients (4.6%) developed dementia. Traumatic brain injury severity and spinal cord injury interacted with age to influence dementia onset; women were at a greater risk of developing dementia earlier than men, all other factors being equal.

Discussion

Risk stratification of patients with CNS trauma by sex is vital in identifying those most likely to develop dementia and in understanding the course and modifying factors.

Relationships between Social Capital, Social Capital Satisfaction, Self-Esteem, and Depression among Elderly Urban Residents: Analysis of Secondary Survey Data

The role that psychological variables play in depression among elderly urban residents has received little research attention. Therefore, the purpose of this study was to examine the relationships between social capital, social capital satisfaction, self-esteem, and depression among elderly urban residents. We used the responses provided by 701 elderly persons to scales assessing social capital (i.e., network, trust), social capital satisfaction, self-esteem, and depression, as part of the Korea Welfare Panel Study (KOWEPS). We conducted a confirmatory factor analysis and tested the validity of a proposed statistical model using structural equation modeling (SEM). The results showed that trust in social capital, social capital satisfaction, and self-esteem were significantly related to depression. Further, social capital satisfaction and self-esteem fully and partially mediated the relationship between trust and depression, respectively. These findings serve as an empirical base upon which social welfare policies can be founded that benefit elderly urban residents with weak social capital, low social capital satisfaction, and poor self-esteem.

Predictors of dementia misclassification when using brief cognitive assessments

BACKGROUND

Brief cognitive assessments can result in false-positive and false-negative dementia misclassification. We aimed to identify predictors of misclassification by 3 brief cognitive assessments; the Mini-Mental State Examination (MMSE), Memory Impairment Screen (MIS) and animal naming (AN).

METHODS

Participants were 824 older adults in the population-based US Aging, Demographics and Memory Study with adjudicated dementia diagnosis (DSM-III-R and DSM-IV criteria) as the reference standard. Predictors of false-negative, false-positive and overall misclassification by the MMSE (cut-point <24), MIS (cut-point <5) and AN (cut-point <9) were analysed separately in multivariate bootstrapped fractional polynomial regression models. Twenty-two candidate predictors included sociodemographics, dementia risk factors and potential sources of test bias.

RESULTS

Misclassification by at least one assessment occurred in 301 (35.7%) participants, whereas only 14 (1.7%) were misclassified by all 3 assessments. There were different patterns of predictors for misclassification by each assessment. Years of education predicts higher false-negatives (odds ratio [OR] 1.23, 95% confidence interval [95% CI] 1.07-1.40) and lower false-positives (OR 0.77, 95% CI 0.70-0.83) by the MMSE. Nursing home residency predicts lower false-negatives (OR 0.15, 95% CI 0.03-0.63) and higher false-positives (OR 4.85, 95% CI 1.27-18.45) by AN. Across the assessments, false-negatives were most consistently predicted by absence of informant-rated poor memory. False-positives were most consistently predicted by age, nursing home residency and non-Caucasian ethnicity (all p < 0.05 in at least 2 models). The only consistent predictor of overall misclassification across all assessments was absence of informant-rated poor memory.

CONCLUSIONS

Dementia is often misclassified when using brief cognitive assessments, largely due to test specific biases.

Interventions involving a major dietary component improve cognitive function in cognitively healthy adults: a systematic review and meta-analysis

Accumulating evidence suggests a role for diet in promoting brain health. The purpose of this systematic review was to (1) quantitatively assess whether interventions with a major dietary component can enhance cognition in cognitively healthy adults and (2) identify responsive domains of cognition to inform the design of future dietary trials. Electronic databases were systematically searched to find eligible randomized controlled trials that assessed the effect of interventions with a major dietary component on cognitive function or incident dementia in adults without known cognitive impairment. Standardized mean differences (SMDs) (95% confidence interval [CI]) were combined using a random-effects meta-analysis, and tests of homogeneity of variance were calculated. Two trials reported dementia outcomes and were qualitatively described. Fifteen trials encompassing 6480 participants were eligible for meta-analysis. Compared to control, intervention improved performance on measures of global cognition (SMD = 0.14, 95% CI 0.01-0.27, P = .05, I² 76%), executive function (SMD = 0.11, 95% CI 0.04-0.18, P = .003, I² 0%), and processing speed (SMD = 0.12, 95% CI 0.05-0.19, P = .001, I² 0%). There was no effect of intervention on delayed memory (SMD = 0.04, 95% CI -0.02 to 0.09, P = .18, I² 4%). Significant heterogeneity and funnel plot asymmetry were detected for global cognition, but removal of studies with high risk of bias did not change the pooled findings. Current evidence is limited but indicates that diverse interventions improve nonmemory cognitive functions during normal cognitive aging. Measures of executive function and processing speed should be considered as feasible end points in future dietary intervention trials.

Do Sociodemographic Factors and Urban Green Space Affect Mental Health Outcomes Among the Urban Elderly Population?

The mounting mental health issues faced by elderly urban residents increase the social and economic costs to society associated with dementia and depression. Therefore, it is necessary to identify the characteristics of elderly urban residents suffering from mental health issues, to address these issues more effectively. We used 2015 Community Health Survey data from the Korea Centers for Disease Control and Prevention to identify the demographic and social characteristics of 11,408 elderly urban residents in relation to stress levels and symptoms of depression in seven metropolitan areas in Korea, and to calculate the odds ratio for urban green space. We found that the prevalence of these mental health issues generally decreased in relation to the ratio of green space of an area. These findings suggest identifying elderly people who are vulnerable to certain mental health issues based on demographic and social characteristics and demonstrate that the ratio of urban green space within a community is an important component in improving mental health outcomes for elderly urban residents. These findings have policy implications for assisting elderly people vulnerable to certain mental health issues and for establishing a green welfare policy targeting this population.

Relevant factors of depression in dementia modifiable by non-pharmacotherapy: a systematic review

Depression in dementia patients is associated with complications such as decreased activities of daily living and decreased quality of life. Because pharmacotherapeutic treatments for depression in dementia patients may have a poor risk-benefit ratio, effective non-pharmacotherapeutic interventions are favourable. However, the development of effective treatments requires the identification of depression-associated factors that can be modified by non-pharmacotherapeutic means in dementia patients. This systematic literature review aimed to identify modifiable factors related to depression and confirm that these factors can be improved by non-pharmacotherapeutic interventions. We searched PubMed, SpringerLink, the Web of Science, and the Cochrane Library for articles published between June 2007 and June 2017. We included studies that investigated causes of depression in dementia patients and excluded studies with unclear dementia diagnostic criteria or operational definitions. Of 9004 records screened, 6 studies were included. The participants included community-dwelling individuals and long-term care facility residents. The severity of dementia varied from mild to severe. After reviewing the studies, we identified five modifiable relevant factors in community-dwelling individuals: (i) pain; (ii) neuropsychiatric symptoms; (iii) cognitive decline; (iv) social isolation; and (v) quality of life. In long-term care facility residents, we identified neuropsychiatric symptoms and quality of life as relevant factors. Our results indicated that non-pharmacological interventions that improve these factors may improve symptoms of depression. A longitudinal study is recommended to clarify the mechanisms underlying depression symptoms and treatment in dementia patients. In addition, further investigation is needed to elucidate the ways in which differing dementia types and severity affect symptoms of depression.

Smoking and Obesity as Risk Factors in Frontotemporal Dementia and Alzheimer's Disease: The HUNT Study

BACKGROUND

Few studies have assessed smoking and obesity together as risk factors for frontotemporal dementia (FTD) and Alzheimer's disease (AD).

OBJECTIVE

To study smoking and obesity as risk factors for FTD and AD.

METHODS

Ninety patients with FTD and 654 patients with AD were compared with 116 cognitively healthy elderly individuals in a longitudinal design with 15-31 years between measurements of risk factors before the dementia diagnosis.

RESULTS

There were no associations between smoking and FTD (p = 0.218; odds ratio [OR]: 0.990; 95% confidence interval [CI]: 0.975-1.006). There were significant associations between obesity and FTD (p = 0.049; OR: 2.629; 95% CI: 1.003-6.894). There were significant associations between both smoking (p = 0.014; OR: 0.987; 95% CI: 0.977-0.997) and obesity (p = 0.015; OR: 2.679; 95% CI: 1.211-5.928) and AD.

CONCLUSION

Our findings suggest that obesity is a shared risk factor for FTD and AD, while smoking plays various roles as a risk factor for FTD and AD.

Challenges and recommendations for the health-economic evaluation of primary prevention programmes for dementia

OBJECTIVE

We aimed to review health-economic evaluations of (hypothetical) intervention programmes for the primary prevention of dementia, and highlight challenges and provide recommendations for future research to estimate its cost-effectiveness.

METHODS

We searched the databases PubMed, MODEM, CEA and NHS for publications on the cost-consequence, -effectiveness, -utility or -benefit analysis of (hypothetical) interventions to reduce the risk of developing dementia for persons without dementia, and described the study characteristics.

RESULTS

Three publications described the evaluation of a hypothetical risk reduction due to physical activity or a multidomain intervention programme. Two studies reported a reduction of care costs. One study yielded two scenarios of increased care costs and one scenario of reduced care costs. Only one study reported the impact in QALY terms, and found a QALY gain.

CONCLUSION

A few studies have evaluated a hypothetical multidomain prevention intervention, and reported that primary dementia prevention is potentially cost-saving or cost-effective. Various challenges remain to evaluate the health-economic impact of prevention interventions, including extrapolation of short-term trial effects, care costs in the dementia-free and life years gained, and accurate representation of usual care. We recommend extensive sensitivity analyses to examine the impact of assumptions regarding these aspects on the outcomes of cost-effectiveness studies.

Neuroimaging and Neurolaw: Drawing the Future of Aging

Human brain-aging is a complex, multidimensional phenomenon. Knowledge of the numerous aspects that revolve around it is therefore essential if not only the medical issues, but also the social, psychological, and legal issues related to this phenomenon are to be managed correctly. In the coming decades, it will be necessary to find solutions to the management of the progressive aging of the population so as to increase the number of individuals that achieve successful aging. The aim of this article is to provide a current overview of the physiopathology of brain aging and of the role and perspectives of neuroimaging in this context. The progressive development of neuroimaging has opened new perspectives in clinical and basic research and it has modified the concept of brain aging. Neuroimaging will play an increasingly important role in the definition of the individual's brain aging in every phase of the physiological and pathological process. However, when the process involved in age-related brain cognitive diseases is being investigated, factors that might affect this process on a clinical and behavioral level (genetic susceptibility, risks factors, endocrine changes) cannot be ignored but must, on the contrary, be integrated into a neuroimaging evaluation to ensure a correct and global management, and they are therefore discussed in this article. Neuroimaging appears important to the correct management of age-related brain cognitive diseases not only within a medical perspective, but also legal, according to a wider approach based on development of relationship between neuroscience and law. The term neurolaw, the neologism born from the relationship between these two disciplines, is an emerging field of study, that deals with various issues in the impact of neurosciences on individual rights. Neuroimaging, enhancing the detection of physiological and pathological brain aging, could give an important contribution to the field of neurolaw in elderly where the full control of cognitive and volitional functions is necessary to maintain a whole series of rights linked to legal capacity. For this reason, in order to provide the clinician and researcher with a broad view of the brain-aging process, the role of neurolaw will be introduced into the brain-aging context.

Health risk prediction models incorporating personality data: Motivation, challenges, and illustration

The age of "big data" in health has ushered in an era of prediction models promising to forecast individual health events. Although many models focus on enhancing the predictive power of medical risk factors with genomic data, a recent proposal is to augment traditional health predictors with psychosocial data, such as personality measures. In this article we provide a general overview of the medical risk prediction models and then discuss the rationale for integrating personality data. We suggest three principles that should guide work in this area if personality data is ultimately to be useful within risk prediction as it is actually practiced in the health care system. These include (a) prediction of specific, priority health outcomes; (b) sufficient incremental validity beyond established biomedical risk factors; and (c) technically responsible model-building that does not overfit the data. We then illustrate the application of these principles in the development of a personality-augmented prediction model for the occurrence of mild cognitive impairment, designed for a primary care setting. We evaluate the results, drawing conclusions for the direction an iterative, programmatic approach would need to take to eventually achieve clinical utility. Although there is great potential for personality measurement to play a key role in the coming era of risk prediction models, the final section reviews the many challenges that must be faced in real-world implementation. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Modifiable Risk Factors Explain Socioeconomic Inequalities in Dementia Risk: Evidence from a Population-Based Prospective Cohort Study

BACKGROUND

Differences in dementia risk across the gradient of socioeconomic status (SES) exist, but their determinants are not well understood.

OBJECTIVE

This study investigates whether health conditions and lifestyle-related risk factors explain the SES inequalities in dementia risk.

METHODS

6,346 participants from the English Longitudinal Study of Ageing were followed up from 2008/2009 until 2014/2015. We used Cox regression adjusted for age, gender, wealth/education, and clustering at the household level to examine the association between SES markers (wealth, education) and time to dementia in a structural equation model including potential mediation or effect modification by a weighted compound score of twelve modifiable risk and protective factors for dementia ('LIfestyle for BRAin health' (LIBRA) score).

RESULTS

During a median follow-up of 6 years, 192 individuals (3.0%) developed dementia. LIBRA scores decreased with increasing wealth and higher educational level. A one-point increase in the LIBRA score was associated with a 13% increase in dementia risk (hazard ratio (HR) = 1.13, 95% confidence interval 1.07-1.19). Higher wealth was associated with a decreased dementia risk (HR = 0.58, 0.39-0.85). Mediation analysis showed that 52% of the risk difference between the highest and lowest wealth tertile was mediated by differences in LIBRA (indirect effect: HR = 0.75, 0.66-0.85). Education was not directly associated with dementia (HR = 1.05, 0.69-1.59), but was a distal risk factor for dementia by explaining differences in wealth and LIBRA scores (indirect effect high education: HR = 0.92, 0.88-0.95).

CONCLUSION

Socioeconomic differences in dementia risk can be partly explained by differences in modifiable health conditions and lifestyle factors.

Modifiable Risk Factors Discriminate Memory Trajectories in Non-Demented Aging: Precision Factors and Targets for Promoting Healthier Brain Aging and Preventing Dementia

BACKGROUND

Non-demented cognitive aging trajectories are characterized by vast level and slope differences and a spectrum of outcomes, including dementia.

OBJECTIVE

The goal of AD risk management (and its corollary, promoting healthy brain aging) is aided by two converging objectives: 1) classifying dynamic distributions of non-demented cognitive trajectories, and 2) identifying modifiable risk-elevating and risk-reducing factors that discriminate stable or normal trajectory patterns from declining or pre-impairment patterns.

METHOD

Using latent class growth analysis we classified three episodic memory aging trajectories for n = 882 older adults (baseline Mage=71.6, SD=8.9, range = 53-95, female=66%): Stable (SMA; above average level, sustained slope), Normal (NMA; average level, moderately declining slope), and Declining (DMA; below average level, substantially declining slope). Using random forest analyses, we simultaneously assessed 17 risk/protective factors from non-modifiable demographic, functional, psychological, and lifestyle domains. Within two age strata (Young-Old, Old-Old), three pairwise prediction analyses identified important discriminating factors.

RESULTS

Prediction analyses revealed that different modifiable risk predictors, both shared and unique across age strata, discriminated SMA (i.e., education, depressive symptoms, living status, body mass index, heart rate, social activity) and DMA (i.e., lifestyle activities [cognitive, self-maintenance, social], grip strength, heart rate, gait) groups.

CONCLUSION

Memory trajectory analyses produced empirical classes varying in level and slope. Prediction analyses revealed different predictors of SMA and DMA that also varied by age strata. Precision approaches for promoting healthier memory aging-and delaying memory impairment-may identify modifiable factors that constitute specific targets for intervention in the differential context of age and non-demented trajectory patterns.

Prevalence of Depression, Anxiety and PTSD in People with Dementia: a Systematic Review and Meta-Analysis

There appears to be a link between depression/anxiety/PTSD and dementia, although the evidence is incomplete and the reason is unclear. Mental illness may cause dementia or may be prodromal or comorbid with dementia, or dementia may trigger a relapse of symptoms in individuals with a history of mental illness. This study examined the link between depression/anxiety/PTSD and dementia by evaluating the prevalence of these disorders in people with dementia, relative to their healthy peers. Existing meta-analyses have examined the prevalence of clinically-significant depression and anxiety in Alzheimer's disease (AD), and depression in frontotemporal dementia (FTD), but have not considered vascular dementia (VaD), dementia with Lewy bodies (DLB), PTSD, or anxiety in FTD. The current meta-analysis compared the prevalence of clinically-significant depression, anxiety and PTSD in the four most common types of dementia (AD, VaD, DLB, FTD) and in unspecified dementia to that of healthy controls (PROSPERO number: CRD42017082086). PubMed, EMBASE, PsycINFO and CINAHL database searches identified 120 eligible studies. Prevalence rates were calculated for depression and anxiety in AD, VaD, DLB, FTD, unspecified dementia, and controls. PTSD data were only available for unspecified dementia. Subgroup analyses indicated that depression, but not anxiety, was more prevalent in people with dementia compared to controls; however, the anxiety analyses were probably under-powered. The results support a link between depression and dementia; however, the link between anxiety or PTSD and dementia remains unclear due to insufficient data. Longitudinal data is now needed to clarify whether depression/anxiety/PTSD may be risk factors for dementia.

How common are neurocognitive disorders in patients with chronic kidney disease and diabetes? Results from a cross-sectional study in a community cohort of patients in North Wales, UK

OBJECTIVE

Chronic kidney disease (CKD) affects nearly 9% of global populations and is strongly associated with older age. Neurocognitive disorders (NCDs), which include mild cognitive impairment and dementia, are rising as a result of ageing populations throughout the world. This investigation's aim is to report the frequency of mild to major NCD in a clinical cohort of adults with mild to moderate CKD and diabetes.

SETTING

Glan Clwyd District general Hospital, North Wales, UK.

PARTICIPANTS

We enrolled 178 patients with CKD and diabetes, aged 55 years and over with an estimated glomerular filtration rate <60 >15 mL/min/1.73 m², attending a specialist renal and diabetic outpatient clinic.

OUTCOME MEASURES

Frequency of mild and major NCD and the association with the stage of CKD was assessed in all patients attending the specialist clinic. The diagnosis of NCD was based on patient and informant interview, case note review, neuropsychological assessment and application of Diagnostic and Statistical Manual of Mental Disorders version 5.

RESULTS

This investigation found 86/178 (48%) of the cohort with an NCD ranging from mild (n=49) to major symptoms (n=37). No association was found with NCD and the stage of CKD. Mild and major NCD was associated poorer outcomes in several cognitive domains, including, language, executive, memory, fluency and attention function (p<0.05).

CONCLUSIONS

This is the first UK investigation to report that cognitive changes occur in a significant number of older adults with CKD and diabetes. The unexpected finding was that prior to cognitive assessment, not any of the cohort had a pre-existing diagnosis of cognitive impairment, suggesting that the current prevalence and incidence rates of NCD in the general population are possibly significantly underestimated. Our findings also suggest that the cognitive function of patients with CKD should be screened and monitored routinely as part of their overall care management.

Primary prevention of dementia: from modifiable risk factors to a public brain health agenda?

INTRODUCTION

With large numbers of people affected, no treatment in sight and continuing demographic change, the prevention of dementia is becoming a central public health issue.

METHODS

We conducted a systematic meta-review including systematic reviews and meta-analyses of longitudinal observational studies on modifiable risk and protective factors for dementia published over the last 5 years.

RESULTS

Compelling evidence on a number of modifiable risk factors, mostly lifestyle factors, is available from longitudinal observational studies to inform primary preventive efforts.

DISCUSSION

Evidence stemming from preventive RCTs is limited. However, multi-domain interventions addressing a variety of risk factors at once seem promising with regard to high-risk individuals (selective preventive approach). However, we argue that it is time to move forward and discuss a public brain health agenda as a universal preventive approach. Based on a risk reduction strategy, the public brain health agenda suggests the following ten key actions: (1) increase physical activity, (2) foster social integration, (3) improve education and foster lifelong learning, (4) provide mentally stimulating workplaces, (5) foster a cognitively active lifestyle, (6) propose a healthy Mediterranean-like diet, (7) reduce alcohol consumption, (8) stop smoking, (9) prevent, diagnose and treat chronic conditions, and (10) reduce anticholinergic medication in the elderly.

Thirty-year trends in dementia: a nationwide population study of Swedish inpatient records

Background

The continuous growth of the current dementia epidemic is contingent on the stability of age- and sex-specific trends over time. However, recent evidence suggests declining or stable trends. The aim of this study was to evaluate the real-world changes in the burden of dementia in older adults in Sweden from 1987 to 2016 by estimating age- and sex-specific incidence of dementia diagnosis in hospital inpatient records (dementia incidence). Differences in trends by sex, age, and educational levels were also examined.

Methods

The entire Swedish population aged 65 years and older was followed up from 1987 to 2016. Age-, sex-, and education-stratified dementia incidence rates for every follow-up year were estimated using the National Patient Register. Hazard ratio of receiving a dementia diagnosis in the inpatient records per 1 calendar year increase was estimated with discrete time logistic models with a complementary log–log link.

Results

After increase, especially in those >85 years of age, dementia incidence started to decrease in the last 5 years of the study period. After 2011, 1 calendar year increase was associated with lower hazard ratio of receiving a hospital diagnosis of dementia. The decrease had the highest magnitude in 70–74-year-olds (−5.5%), followed by 75–79-year-olds (−4.5%) and 80–84-year-olds (−4.0%). The decrease was present in both sexes and at all educational levels up to 90 years of age. Age was associated with the level of dementia incidence, and the trends differed by age group. Educational gradient was observed. University-educated older adults had the lowest rates of dementia. However, the trend over time did not substantially differ by sex or educational level.

Conclusion

Our results provide more evidence that dementia incidence may be declining. They also suggest that at least in hospitals, the number of new patients with dementia may decrease in the future.

Validity and reliability of the Brazilian Portuguese version of the Australian National University - Alzheimer's Disease Risk Index (ANU-ADRI)

The ANU-ADRI is a self-report tool that assesses risk for Alzheimer’s Disease (AD).

Occupational cognitive complexity in earlier adulthood is associated with brain structure and cognitive health in midlife: The CARDIA study

OBJECTIVE

In line with cognitive reserve theory, higher occupational cognitive complexity is associated with reduced cognitive decline in older adulthood. How and when occupational cognitive complexity first exerts protective effects during the life span remains unclear. We investigated associations between occupational cognitive complexity during early to midadulthood and brain structure and cognition in midlife.

METHOD

Participants were 669 adults from the Coronary Artery Risk Development in Young Adults study (aged 18-30 years at baseline, 52% female, 38% Black). We calculated scores reflecting occupational cognitive complexity using Census Occupation Codes (years 10 and 15) and Occupational Information Network (O*NET) data. At year 25, participants had structural brain magnetic resonance imaging, diffusion tensor imaging, and cognitive testing (Rey Auditory Verbal Learning Test, Digit Symbol Substitution Test, Stroop). In adjusted mixed models, we examined associations between occupational cognitive complexity during early to midadulthood and midlife brain structure, specifically gray matter volume and white matter fractional anisotropy, and cognition in midlife (all outcomes converted to z-scores).

RESULTS

Higher occupational cognitive complexity was associated with greater white matter fractional anisotropy (estimate = 0.10, p = .01) but not gray matter volume. Higher occupational cognitive complexity was associated with better Digit Symbol Substitution Test (estimate = 0.13, p < .001) and Stroop (estimate = 0.09, p = .01) performance but not Rey Auditory Verbal Learning Test performance.

CONCLUSIONS

Occupational cognitive complexity earlier in adulthood is associated with better white matter integrity, processing speed, and executive function in midlife. These associations may capture how occupational cognitive complexity contributes to cognitive reserve. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Early Manifestations of Brain Aging in Mice Due to Low Dietary Folate and Mild MTHFR Deficiency

Folate is an important B vitamin required for methylation reactions, nucleotide and neurotransmitter synthesis, and maintenance of homocysteine at nontoxic levels. Its metabolism is tightly linked to that of choline, a precursor to acetylcholine and membrane phospholipids. Low folate intake and genetic variants in folate metabolism, such as the methylenetetrahydrofolate reductase (MTHFR) 677 C>T polymorphism, have been suggested to impact brain function and increase the risk for cognitive decline and late-onset Alzheimer's disease. Our study aimed to assess the impact of genetic and nutritional disturbances in folate metabolism, and their potential interaction, on features of cognitive decline and brain biochemistry in a mouse model. Wild-type and Mthfr^+/- mice, a model for the MTHFR 677 C>T polymorphism, were fed control or folate-deficient diets from weaning until 8 and 10 months of age. We observed short-term memory impairment measured by the novel object paradigm, altered transcriptional levels of synaptic markers and epigenetic enzymes, as well as impaired choline metabolism due to the Mthfr^+/- genotype in cortex or hippocampus. We also detected changes in mRNA levels of Presenillin-1, neurotrophic factors, one-carbon metabolic and epigenetic enzymes, as well as reduced levels of S-adenosylmethionine and acetylcholine, due to the folate-deficient diet. These findings shed further insights into the mechanisms by which genetic and dietary folate metabolic disturbances increase the risk for cognitive decline and suggest that these mechanisms are distinct.

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.

Physical fitness and dementia risk in the very old: a study of the Lothian Birth Cohort 1921

BACKGROUND

Previous studies have demonstrated that individual measures of fitness - such as reduced pulmonary function, slow walking speed and weak handgrip - are associated with an increased risk of dementia. Only a minority of participants included in these studies were aged over 80. The aim of this study was therefore to investigate the association between physical fitness and dementia in the oldest old.

METHODS

Subjects (n = 488) were enrolled in the Lothian Birth Cohort 1921 and aged 79 at baseline. Dementia cases arising after enrolment were determined using data from death certificates, electronic patient records and clinical reviews. Fitness measures included grip strength, forced expiratory volume in 1 s (FEV₁) and walking speed over 6 m, measured at 79 years. Dementia risk associated with each fitness variable was initially determined by logistic regression analysis, followed by Cox regression analysis, where death was considered as a competing risk. APOE ε4 status, age, sex, height, childhood IQ, smoking, history of cardiovascular or cerebrovascular disease, hypertension and diabetes were included as additional variables. Cumulative incidence graphs were calculated using Aalen-Johansen Estimator.

RESULTS

Although initial results indicated that greater FEV₁ was associated with an increased risk of dementia (OR (odds ratio per unit increase) 1.93, p = 0.03, n = 416), taking into account the competing risk of mortality, none of the fitness measures were found to be associated with dementia; FEV₁ (HR (hazard ratio per unit increase) 1.30, p = 0.37, n = 416), grip strength (HR 0.98, p = 0.35, n = 416), walking speed (HR 0.99, p = 0.90, n = 416). The presence of an APOE ɛ4 allele was however an important predictor for dementia (HR 2.85, p < 0.001, n = 416). Cumulative incidence graphs supported these findings, with an increased risk of dementia for APOE ɛ4 carriers compared with non-carriers. While increased FEV₁ was associated with reduced risk of death, there was no reduction in risk for dementia.

CONCLUSIONS

In contrast to previous studies, this study found that lower fitness beyond age 79 was not a risk factor for subsequent dementia. This finding is not explained by those with poorer physical fitness, who would have been more likely to develop dementia, having died before onset of dementia symptoms.

Chronic consumption of a western diet modifies the DNA methylation profile in the frontal cortex of mice

In our previous work in mice, we have shown that chronic consumption of a Western diet (WD; 42% kcal fat, 0.2% total cholesterol and 34% sucrose) is correlated with impaired cognitive function. Cognitive decline has also been associated with alterations in DNA methylation. Additionally, although there have been many studies analyzing the effect of maternal consumption of a WD on DNA methylation in the offspring, few studies have analyzed how an individual's consumption of a WD can impact his/her DNA methylation. Since the frontal cortex is involved in the regulation of cognitive function and is often affected in cases of cognitive decline, this study aimed to examine how chronic consumption of a WD affects DNA methylation in the frontal cortex of mice. Eight-week-old male mice were fed either a control diet (CD) or a WD for 12 weeks, after which time alterations in DNA methylation were analyzed. Assessment of global DNA methylation in the frontal cortex using dot blot analysis revealed that there was a decrease in global DNA methylation in the WD-fed mice compared with the CD-fed mice. Bioinformatic analysis identified several networks and pathways containing genes displaying differential methylation, particularly those involved in metabolism, cell adhesion and cytoskeleton integrity, inflammation and neurological function. In conclusion, the results from this study suggest that consumption of a WD alters DNA methylation in the frontal cortex of mice and could provide one of the mechanisms by which consumption of a WD impairs cognitive function.

Greater Cognitive Deficits with Sleep-disordered Breathing among Individuals with Genetic Susceptibility to Alzheimer Disease. The Multi-Ethnic Study of Atherosclerosis

RATIONALE

There are conflicting findings regarding the link between sleep apnea and cognitive dysfunction.

OBJECTIVES

Investigate associations between indicators of sleep-disordered breathing (SDB) and cognitive function in the Multi-Ethnic Study of Atherosclerosis and assess effect modification by the apolipoprotein ε-4 (APOE-ε4) allele.

METHODS

A diverse population (N = 1,752) underwent type 2 in-home polysomnography, which included measurement of percentage sleep time less than 90% oxyhemoglobin saturation (%Sat < 90%) and apnea-hypopnea index (AHI). Epworth Sleepiness Scale score (ESS) and sleep apnea syndrome (SAS; AHI ≥ 5 and ESS > 10) were also analyzed. Cognitive outcomes included the Cognitive Abilities Screening Instrument; Digit Symbol Coding (DSC) test; and Digit Span Tests (DST) Forward and Backward.

RESULTS

Participants were 45.4% men, aged 68.1 years (SD, 9.1 yr) with a median AHI of 9.0 and mean ESS of 6.0. Approximately 9.7% had SAS, and 26.8% had at least one copy of the APOE-ε4 allele. In adjusted analyses, a 1-SD increase in %Sat < 90% and ESS score were associated with a poorer attention and memory assessed by the DST Forward score (β = -0.12 [SE, 0.06] and β = -0.13 [SE, 0.06], respectively; P ≤ 0.05). SAS and higher ESS scores were also associated with poorer attention and processing speed as measured by the DSC (β = -0.69 [SE, 0.35] and β = -1.42 [SE, 0.35], respectively; P < 0.05). The presence of APOE-ε4 allele modified the associations of %Sat < 90% with DST forward and of ESS with DSC (P_interaction ≤ 0.05).

CONCLUSIONS

Overnight hypoxemia and sleepiness were associated with cognition. The average effect estimates were small, similar to effect estimates for several other individual dementia risk factors. Associations were strongest in APOE-ε4 risk allele carriers. Our results (1) suggest that SDB be considered among a group of modifiable dementia risk factors, and (2) highlight the potential vulnerability of APOE-ε4 risk allele carriers with SDB.

Development of a risk score for the prediction of incident dementia in older adults using a frailty index and health checkup data: The JAGES longitudinal study

In Japan, the prevalence of dementia is expected to reach 4.7 million by 2025. This study aimed to develop a risk score for the prediction of incident dementia in community-dwelling older adults. In this longitudinal observational study, we used data from the Japan Gerontological Evaluation Study (JAGES) conducted in K City. We performed Cox regression analyses to develop three risk score models for the prediction of incident dementia in older adults using a frailty index and health checkup data. Analyses of the area under the receiver operating characteristic curve were conducted to compare the models' predictive abilities. We identified 6656 (9.2%) individuals who developed incident dementia during the observation period. The C-statistics of the risk scores ranged from 0.733 to 0.790. The risk score models were able to predict incident dementia in older adults and may help non-medical professionals detect dementia risk at an early stage.

Brain complications of diabetes mellitus: a cross-sectional study of awareness among individuals with diabetes and the general population in Ireland

AIMS

To identify awareness of potential brain complications of diabetes among individuals with diabetes and the public.

METHODS

For this observational, cross-sectional survey study, we recruited consecutive adult attendees of a specialist diabetes clinic and two primary care practices. Primary care attendees represented members of the general population of Ireland. An interviewer-administered questionnaire was used to gather data on respondents' awareness of brain complications of diabetes and modifiable risk factors for dementia. Multivariable logistic regression was undertaken to identify variables independently associated with awareness.

RESULTS

Respondents included a total of 502 adults: 250 in the diabetes group (37% women, mean age 63 ± 14 years, 88% with Type 2 diabetes) and 252 in the general population group (51% women, mean age 47 ± 17 years, 7% with Type 2 diabetes). The diabetes group had significantly greater awareness of diabetes complications, except for depression, compared with the general population group. In the group as a whole, respondent awareness of dementia (35%) and memory problems (47%) as potential complications of diabetes was poor compared with awareness of kidney (84%) and eye damage (84%). Respondents were 1.5 times more likely to identify that individuals can modify their risk of developing Type 2 diabetes than their risk of dementia.

CONCLUSIONS

This study shows that there is poor awareness of brain complications of diabetes among individuals with diabetes and the general population in Ireland. The results suggest a need for expansion of public awareness campaigns and diabetes education programmes to promote awareness of the brain complications of diabetes and of the modifiable risk factors for dementia, as part of a life-course approach to dementia prevention.

Modifiable dementia risk score to study heterogeneity in treatment effect of a dementia prevention trial: a post hoc analysis in the preDIVA trial using the LIBRA index

Background

Selecting high-risk participants for dementia prevention trials based on a modifiable dementia risk score may be advantageous, as it increases the opportunity for intervention. We studied whether a multi-domain intervention can prevent all-cause dementia and cognitive decline in older people across three different levels of a modifiable dementia risk score.

Methods

Prevention of Dementia by Intensive Vascular Care (preDIVA) is a randomised controlled trial studying the effect of multi-domain vascular care during 6–8 years on incident all-cause dementia in community-dwelling people aged 70–78 years. For this post hoc analysis, we stratified preDIVA participants in tertiles based on their baseline LIfestyle for BRAin Health (LIBRA) index, a modifiable dementia risk score. With Cox proportional hazards regression, the intervention effect on dementia was assessed. The effect on cognition was measured every 2 years with the Mini-Mental State Examination and Visual Association Test.

Results

Dementia developed in 220 of 3274 (6.7%) participants. In participants with a low, intermediate and high LIBRA index, the hazard ratio (HR) of the intervention on incident dementia was respectively 0.71 (95% CI 0.45–1.12), 1.06 (95% CI 0.66–1.69) and 1.02 (95% CI 0.64–1.62). Also, when adding the non-modifiable risk factors age, education and sex to the index, results were comparable (respectively HR 0.88, 95% CI 0.54–1.43; HR 0.91, 95% CI 0.57–1.47; HR 0.92, 95% CI 0.59–1.41). There was no statistically significant intervention effect on cognition during follow-up across the LIBRA groups.

Conclusions

In the preDIVA study population aged 70–78 years, the LIBRA modifiable dementia risk score did not identify a (high-)risk group in whom the multi-domain intervention was effective in preventing dementia or cognitive decline.

Trial registration

International Standard Randomised Controlled Trial Number registry, ISRCTN29711771. Registered on 14 February 2006.

Electronic supplementary material

The online version of this article (10.1186/s13195-018-0389-4) contains supplementary material, which is available to authorized users.

Visual Evaluation of Medial Temporal Lobe Atrophy as a Clinical Marker of Conversion from Mild Cognitive Impairment to Dementia and for Predicting Progression in Patients with Mild Cognitive Impairment and Mild Alzheimer's Disease

BACKGROUND/AIMS

To evaluate whether visual assessment of medial temporal lobe atrophy (vaMTA) can predict 2-year conversion from mild cognitive impairment (MCI) to dementia and progression of MCI and Alzheimer's disease dementia as measured by the Clinical Dementia Rating Scale Sum of Boxes score (CDR-SB).

METHODS

vaMTA was performed in 94 patients with MCI according to the Winblad criteria and in 124 patients with AD according to ICD-10 and NINCDS-ADRDA criteria. Demographic data, the Consortium to Establish a Registry for Alzheimer's Disease 10-word delayed recall, APOE ɛ4 status, Cornell Scale for Depression in Dementia, and comorbid hypertension were used as covariates.

RESULTS

vaMTA was associated with MCI conversion in an unadjusted model but not in an adjusted model (p = 0.075), where delayed recall and APOE ɛ4 status were significant predictors. With CDR-SB change as the outcome, an interaction between vaMTA and diagnosis was found, but in the adjusted model only delayed recall and age were significant predictors. For vaMTA below 2, the association between vaMTA and CDR-SB change differed between diagnostic groups. Similar results were found based on a trajectory analysis.

CONCLUSION

In adjusted models, memory function, APOE ɛ4 status and age were significant predictors of disease progression, not vaMTA. The association between vaMTA and CDR-SB change was different in patients with MCI and Alzheimer's disease dementia.

The effect of lifestyle on late-life cognitive change under different socioeconomic status

This study aimed to identify lifestyle factors associated with cognitive change and to explore whether the effect of lifestyle varies by socioeconomic status (SES). Participants aged 65 years and older were recruited from elderly health checkup programs from 2011 to 2013 in Taiwan. Neuropsychological tests, including tests of global cognition, logical memory, executive function, verbal fluency and attention, were administered at baseline (N = 603) and 2 years later (N = 509). After literature review, 9 lifestyle factors and 3 SES indicators were chosen and their effects on cognitive change were evaluated using linear regression adjusting for age, sex, education, APOE ε4 status, and baseline cognitive score. Five lifestyle factors (high vegetable and fish intake, regular exercise, not smoking, and light to moderate alcohol consumption) and 3 SES indicators [annual household income (> 33,333 USD vs. less), occupational complexity (high vs. low mental demanding job), and years of education (> 12 years vs. less)] were found to be protective against cognitive decline (P < 0.1 in any cognitive domains, ß ranging from 0.06 to 0.38). After further adjusting for all the lifestyle and SES factors, fish intake, higher income and occupational complexity remained protective. Significant interactions were found between a healthful lifestyle (defined as having ≥ 3 healthful lifestyle factors) and income on changes of global cognition and verbal fluency (P_interaction = 0.02 and 0.04). The protective effect of a healthful lifestyle was observed only among participants with lower income in global cognition and logical memory [ß = 0.17, 95% confidence interval (CI) = 0.07–0.26; ß = 0.30, 95% CI = 0.14–0.46]. To the best of our knowledge, this study for the first time explored how the interactions of lifestyle and SES affect cognitive change. Our findings will aid in developing dementia prevention programs and reduce health inequalities.

Prevalence of dementia in mainland China, Hong Kong and Taiwan: an updated systematic review and meta-analysis

BACKGROUND

There are several existing systematic reviews of prevalence of dementia for mainland China, Hong Kong and Taiwan, but several studies have been newly reported. The aim of this study is to update prevalence data in this region and test for variation across geographical areas and time periods using the new dataset.

METHODS

Twenty prevalence studies identified from World Alzheimer Report 2015 (January 2011-March 2015) and an updated search (March 2015-February 2017) were added to the original dataset (N = 76). Meta-regression was used to investigate geographical variation and time trends, taking methodological factors and characteristics of study population into account, and to estimate prevalence and number of people with dementia by geographical area.

RESULTS

Compared with northern China, the prevalence of dementia was lower in the central China [-1.0; 95% confidence interval (CI):-2.2, 0.3], south China (-1.7; 95% CI: -3.1, -0.3), Hong Kong and Taiwan (-3.0; 95% CI: -5.0, -1.0) but appeared to be higher in western China (2.8; 95% CI: 0.1, 5.5) after adjusting for methodological variation. The increasing trend from pre-1990 to post-2010 periods was considerably attenuated when taking into account methodological factors and geographical areas. The updated estimated number of people with dementia in all these areas is 9.5 million (5.3%; 95% CI: 4.3, 6.3) in the population aged 60 or above.

CONCLUSIONS

Geographical variation in dementia prevalence is confirmed in this update, whereas evidence on increasing trends is still insufficient. Differing societal development across areas provides an opportunity to investigate risk factors at the population level operating across diverse life course experiences. Such research could advance global primary prevention of dementia.

Does incipient dementia explain normal cognitive decline determinants? Lothian birth cohort 1921

The presence of an apolipoprotein E (APOE) ε4 allele, lower physical fitness, smoking, and lower serum vitamin B-12 have been reported as contributing to poorer cognitive function in LBC1921 at age 79, after adjusting for childhood intelligence. Because incident dementia was not previously ascertained within LBC1921, it is possible that preclinical or unrecognized cases at age 79 influenced findings. Dementia cases arising over approximately 16 years of follow-up were determined by a consensus using evidence from electronic medical records, death certificates, and clinical reviews. The analyses from the original reports were repeated after the exclusion of those who had developed dementia. In a subsequent set of analyses, the authors considered the potential impact of terminal decline, excluding those participants who died within 4 years of baseline testing. Positive APOE ε4 status was found to be associated with poorer Logical Memory (Wechsler, 1987) at age 79 (F(1, 355) = 8.16, p = .005, ηp2 = 0.022; n = 359) and lower Moray House Test (Scottish Council for Research in Education, 1933) score at age 79 (F(1, 357) = 4.27, p = .04, ηp2 = 0.012; n = 363). Lower age 79 IQ was associated with smoking (F(2, 360) = 3.67, p = .026, ηp2 = 0.020; n = 367), lower vitamin B-12 (Sβ = 0.11, p = .014; n = 367), and poorer physical fitness (Sβ = 0.21, p < .001; n = 359). Only the relationship with physical fitness remained significant after excluding those who died within 4 years of baseline (Sβ = 0.203, p < .001; n = 310). Unrecognized dementia had little or no effect on determinants of lifetime cognitive ageing in LBC1921. Terminal decline may have accounted for the associations with age 11 to age 79 cognitive change. (PsycINFO Database Record

APOEε4 Genotype and Hypertension Modify 8-year Cortical Thinning: Five Occasion Evidence from the Seattle Longitudinal Study

We investigated individual differences in longitudinal trajectories of brain aging in cognitively normal healthy adults from the Seattle Longitudinal Study covering 8 years of longitudinal change (across 5 occasions) in cortical thickness in 249 midlife and older adults (52-95 years old). We aimed to understand true brain change; examine the influence of salient risk factors that modify an individual's rate of cortical thinning; and compare cross-sectional age-related differences in cortical thickness to longitudinal within-person cortical thinning. We used Multivariate Multilevel Modeling to simultaneously model dependencies among 5 lobar composites (Frontal, Parietal, Temporal, Occipital, and Cingulate [CING]) and account for the longitudinal nature of the data. Results indicate (1) all 5 lobar composites significantly atrophied across 8 years, showing nonlinear longitudinal rate of cortical thinning decelerated over time, (2) longitudinal thinning was significantly altered by hypertension and Apolipoprotein-E ε4 (APOEε4), varying by location: Frontal and CING thinned more rapidly in APOEε4 carriers. Notably, thinning of parietal and occipital cortex showed synergistic effect of combined risk factors, where individuals who were both APOEε4 carriers and hypertensive had significantly greater 8-year thinning than those with either risk factor alone or neither risk factor, (3) longitudinal thinning was 3 times greater than cross-sectional estimates of age-related differences in thickness in parietal and occipital cortices.

Conditions Associated with Essential Tremor in Veterans: A Potential Role for Chronic Stress

Background

Increased depression, hearing loss, dementia, alcoholism, and mortality in essential tremor patients remain unexplained. We investigated whether conditions associated with tremor are linked to chronic stress.

Methods

The FY2013 Veterans Affairs database was queried for 38 selected dual diagnosis combinations in 5,854,223 veterans aged 21–95 years.

Results

Post-traumatic stress disorder, anxiety, and depression were the most common psychiatric diagnoses in tremor patients, with the odds ratio exceeding 2 in all 15-year cohorts. Depending on age, patients with essential tremor were more likely than those without to have obsessive–compulsive disorder, bipolar illness, schizophrenia, use tobacco and abuse alcohol, have hypertension, obesity, hyperlipidemia, diabetes, vitamin D deficiency, coronary and cerebrovascular diseases, congestive heart failure, stroke, asthma, hypothyroidism, irritable bowel syndrome, renal insufficiency, alcoholic liver disease, hearing loss, glaucoma, macular degeneration, migraine, epilepsy, idiopathic polyneuropathy, history of head trauma, and ‘Alzheimer’s dementia. In contrast, lung and colorectal cancer, amyotrophic lateral sclerosis, psychostimulant abuse, and rheumatoid arthritis were not more common.

Discussion

Post-traumatic stress disorder, anxiety, and depression, strongly associated with essential tremor, are known risk factors for poor health habits, tobacco use and alcohol abuse; collectively these are risk factors for vascular disease, with further negative health consequences for multiple organ systems. As essential tremor is associated with all these conditions, we propose that chronic stress is not only responsible for the conditions associated with tremor but in some cases itself directly and indirectly induces essential tremor, so that tremor and poor health share a common cause.

Long-term risk of dementia among people with traumatic brain injury in Denmark: a population-based observational cohort study

BACKGROUND

Traumatic brain injury (TBI) has been associated with increased risk of dementia; however, large-scale studies with long follow-up have been scarce. We investigated the association between TBI, including severity and number of TBIs, and the subsequent long-term risk of dementia.

METHODS

We did a nationwide population-based observational cohort study in Denmark using information on citizens from national registries. We used the Danish Civil Registration System to establish a population-based cohort consisting of all people born in Denmark who were living in the country on Jan 1, 1995, and who were at least 50 years old at some point during follow-up (between 1999 and 2013). We obtained information on TBIs from the Danish National Patient Register (NPR), and obtained information on dementia by combining data recorded in the NPR, the Danish Psychiatric Central Register, and the Danish National Prescription Registry (DNPR). The long-term risk of dementia after TBI was established using survival analysis. We used three prespecified models for each of the three analyses: different time periods since the TBI, multiple TBIs, and sex. The first model adjusted for sociodemographic factors, the second model added medical and neurological comorbidities, and the third added psychiatric comorbidities.

FINDINGS

We used data from a cohort of 2 794 852 people for a total of 27 632 020 person-years (mean 9·89 years per patient) at risk of dementia. 132 093 individuals (4·7%) had at least one TBI during 1977-2013, and 126 734 (4·5%) had incident dementia during 1999-2013. The fully adjusted risk of all-cause dementia in people with a history of TBI was higher (hazard ratio [HR] 1·24, 95% CI 1·21-1·27) than in those without a history of TBI, as was the specific risk of Alzheimer's disease (1·16, 1·12-1·22). The risk of dementia was highest in the first 6 months after TBI (HR 4·06, 3·79-4·34) and also increased with increasing number of events (1·22, 1·19-1·25 with one TBI to 2·83, 2·14-3·75 with five or more TBIs). Furthermore, TBI was associated with a higher risk of dementia (1·29, 1·26-1·33) in people with TBI than in individuals with a non-TBI fracture not involving the skull or spine. The younger a person was when sustaining a TBI, the higher the HRs for dementia when stratified by time since TBI.

INTERPRETATION

TBI was associated with an increased risk of dementia both compared with people without a history of TBI and with people with non-TBI trauma. Greater efforts to prevent TBI and identify strategies to ameliorate the risk and impact of subsequent dementia are needed.

FUNDING

Lundbeck Foundation.

Modifiable Risk Factors for Prevention of Dementia in Midlife, Late Life and the Oldest-Old: Validation of the LIBRA Index

BACKGROUND

Recently, the LIfestyle for BRAin health (LIBRA) index was developed to assess an individual's prevention potential for dementia.

OBJECTIVE

We investigated the predictive validity of the LIBRA index for incident dementia in midlife, late life, and the oldest-old.

METHODS

9,387 non-demented individuals were recruited from the European population-based DESCRIPA study. An individual's LIBRA index was calculated solely based on modifiable risk factors: depression, diabetes, physical activity, hypertension, obesity, smoking, hypercholesterolemia, coronary heart disease, and mild/moderate alcohol use. Cox regression was used to test the predictive validity of LIBRA for dementia at follow-up (mean 7.2 y, range 1-16).

RESULTS

In midlife (55-69 y, n = 3,256) and late life (70-79 y, n = 4,320), the risk for dementia increased with higher LIBRA scores. Individuals in the intermediate- and high-risk groups had a higher risk of dementia than those in the low-risk group. In the oldest-old (80-97 y, n = 1,811), higher LIBRA scores did not increase the risk for dementia.

CONCLUSION

LIBRA might be a useful tool to identify individuals for primary prevention interventions of dementia in midlife, and maybe in late life, but not in the oldest-old.

Perspectives on Communicating Biomarker-Based Assessments of Alzheimer's Disease to Cognitively Healthy Individuals

In clinical trials which target pathophysiological mechanisms associated with Alzheimer's disease, research participants who are recruited based on biomarker test results should be informed about their increased risk of developing Alzheimer's dementia. This paper presents the results of a qualitative focus group study of attitudes and concerns toward learning information about biomarker-based risk status among healthy research participants in the United Kingdom and Spain and people with dementia and their supporters/caregivers from countries represented in the European Working Group of People with Dementia of Alzheimer Europe. The study identified expectations related to learning risk status and preferences related to the content, quality, and follow-up of the disclosure process. The latter emphasize distinctions between risk and diagnoses, the importance of clear information about risk, and suggestions for risk reduction, as well as expectations for follow up and support. The implications of these preferences for practice are discussed. Providing details of research participants' experience and views may serve as a guide for the development of processes for the responsible disclosure of Alzheimer's disease biomarkers.

Asymmetry of Hippocampus and Amygdala Defect in Subjective Cognitive Decline Among the Community Dwelling Chinese

Background: Subjective cognitive decline (SCD) may be the first clinical sign of Alzheimer's disease (AD). SCD individuals with normal cognition may already have significant medial temporal lobe atrophy. However, few studies have been devoted to exploring the alteration of left-right asymmetry with hippocampus and amygdala in SCD. The aim of this study was to compare SCD individuals with amnestic mild cognitive impairment (MCI) patients and the normal population for volume and asymmetry of hippocampus, amygdala and temporal horn, and to assess their relationship with cognitive function in elderly population living in China. Methods: 111 SCD, 30 MCI, and 67 healthy controls (HC) underwent a standard T1-weighted MRI, from which the volumes of the hippocampus and amygdala were calculated and compared. Then we evaluated the pattern and extent of asymmetry in hippocampus and amygdala of these samples. Furthermore, we also investigated the relationship between the altered brain regions and cognitive function. Results: Among the three groups, SCD showed more depressive symptoms (p < 0.001) and higher percentage of heart disease (16.4% vs. 35.1%, p = 0.007) than controls. In terms of brain data, significant differences were found in the volume and asymmetry of both hippocampus and amygdala among the three groups (P < 0.05). In logistic analysis controlled by age, gender, education level, depression symptoms, anxiety symptom, somatic disease and lifestyle in terms of smoking, both SCD and MCI individuals showed significant decreased right hippocampal and amygdala volume than controls. For asymmetry pattern, a ladder-shaped difference of left-larger-than-right asymmetry was found in amygdala with MCI>SCD>HC, and an opposite asymmetry of left-less-than-right pattern was found with HC>SCD>MCI in hippocampus. Furthermore, correlation was shown between the volume of right hippocampus and right amygdala with MMSE and MoCA in SCD group. Conclusion: Our results supported that SCD individuals are biologically distinguishable from HC, and this may relate to cognitive impairment, although more longitudinal studies are need to investigate this further.Moreover, different levels of asymmetry in hippocampus and amygdala might be a potential dividing factor to differentiate clinical diagnosis.

Lifestyle for Brain Health (LIBRA): a new model for dementia prevention

OBJECTIVE

Modifiable risk factors for dementia were recently identified and compiled in a systematic review. The 'Lifestyle for Brain Health' (LIBRA) score, reflecting someone's potential for dementia prevention, was studied in a large longitudinal population-based sample with respect to predicting cognitive change over an observation period of up to 16 years.

METHODS

Lifestyle for Brain Health was calculated at baseline for 949 participants aged 50-81 years from the Maastricht Ageing Study. The predictive value of LIBRA for incident dementia and cognitive impairment was examined by using Cox proportional hazard models and by testing its relation with cognitive decline.

RESULTS

Lifestyle for Brain Health predicted future risk of dementia, as well as risk of cognitive impairment. A one-point increase in LIBRA score related to 19% higher risk for dementia and 9% higher risk for cognitive impairment. LIBRA predicted rate of decline in processing speed, but not memory or executive functioning.

CONCLUSIONS

Lifestyle for Brain Health (LIBRA) may help in identifying and monitoring risk status in dementia-prevention programmes, by targeting modifiable, lifestyle-related risk factors. Copyright © 2017 John Wiley & Sons, Ltd.