Relationship between education and dementia: an updated systematic review

Lower Levels of Education Are Associated with Cognitive Impairment in the Old Order Amish

BACKGROUND

Lower education has been reported to be associated with dementia. However, many studies have been done in settings where 12 years of formal education is the standard. Formal schooling in the Old Order Amish communities (OOA) ends at 8th grade which, along with their genetic homogeneity, makes it an interesting population to study the effect of education on cognitive impairment.

OBJECTIVE

The objective of this study was to examine the association of education with cognitive function in individuals from the OOA. We hypothesized that small differences in educational attainment at lower levels of formal education were associated with risk for cognitive impairment.

METHODS

Data of 2,426 individuals from the OOA aged 54-99 were analyzed. The Modified Mini-Mental State Examination (3MS-R) was used to classify participants as CI or normal. Individuals were classified into three education categories: <8, 8, and >8 years of education. To measure the association of education with cognitive status, a logistic regression model was performed adding age and sex as covariates.

RESULTS

Our results showed that individuals who attained lowest levels of education (<8 and 8) had a higher probability of becoming cognitvely impaired compared with people attending >8 years (OR = 2.96 and 1.85).

CONCLUSION

Even within a setting of low levels of formal education, small differences in educational attainment can still be associated with the risk of cognitive impairment. Given the homogeneity of the OOA, these results are less likely to be biased by differences in socioeconomic backgrounds.

Association between the occurrence of albuminuria and the risk of early dementia among older people upon health examination: a community-based cohort study in Taiwan

OBJECTIVES

This study aimed to investigate the associations between biochemical markers, renal function, health behaviours and dementia among older people.

DESIGN

A retrospective cohort study.

SETTING

Community-based health examination database from Taipei city.

PARTICIPANTS

In total, 35 434 older people were included from February 2005 to December 2012. To assess changes in renal function, we selected participants who attended health examinations at least twice and responded to the AD8 questionnaire in 2012. We excluded those with dementia at baseline.

PRIMARY OUTCOME MEASURES

Early dementia was assessed using the AD8 questionnaire in 2012. Explanatory variables included demographic factors, health behaviours, biochemical markers and renal function. We used a Cox proportional hazard model to estimate the HR for early dementia onset.

RESULTS

Individuals with mild albuminuria (HR 1.228; 95% CI 1.066 to 1.414), lower eGFR (HR 1.549; 95% CI 1.319 to 1.820) and higher age (HR 1.022; 95% CI 1.015 to 1.028) were associated with a high risk of early dementia. Older people with no alcohol intake (HR 0.872; 95% CI 0.794 to 0.958), and higher education levels (HR 0.647; 95% CI 0.589 to 0.710) were at a low risk of early dementia.

CONCLUSIONS

Elevated mild albuminuria and low eGFR were associated with a high risk of early dementia in this community-based cohort. Routine health examinations for older people can help screen out the high-risk population, and clinical management might reduce or delay the risk of early dementia.

What does (low) education mean in terms of dementia risk? A systematic review and meta-analysis highlighting inconsistency in measuring and operationalising education

Low education is considered an important modifiable risk factor for dementia worldwide, despite the lack of a formal consensus definition of low education. The primary aim of this systematic review was to document and address the inconsistency in measuring and operationalising education in dementia studies. A secondary aim was to consider the dose of education required to reduce dementia risk. The protocol was registered at PROSPERO with registration ID CRD42018096168. CINAHL, Cochrane, PsycInfo, and Pubmed databases were searched using terms related to education, dementia and/or MCI, and incidence. Studies were eligible for inclusion if a risk ratio for education and any dementia, Alzheimer's Disease (AD), Vascular Dementia (VaD) or Mild Cognitive Impairment (MCI) was reported in a population cognitively healthy at baseline. Sample sizes for 65 studies meeting selection criteria ranged from 152 to 12,881, representing populations from 24 countries. Risk of bias, assessed using a tool designed specifically for dementia risk studies, was found to be medium or low for all studies. There were 23 continuous, 29 dichotomous, and 31 categorical operationalisations of education reported. Random effects meta-analyses from continuous operationalisations suggested each year of education reduced risk by eight percent for AD (95% CI:5-12%) and seven percent for any dementia (95% CI:6-9%). Dichotomous operationalisations indicated an increased risk for low education of 45% (95% CI:29-63%) for any dementia and 85% (95% CI:56-118%) for AD, however definitions of low education were heterogeneous, ranging from zero to 12 years. There were too few studies to produce summary ratios for VaD or MCI. We conclude that, while the evidence of an association between low education and dementia incidence is robust, inconsistency in the definition, measurement and operationalisation of education hinders the translation of this evidence into practical policy recommendations to reduce dementia risk.

Urban green space, tree canopy and 11-year risk of dementia in a cohort of 109,688 Australians

INTRODUCTION

Urban greening is a climate change-related policy with considerable health benefits. But do these benefits extend to prevention of dementia and, if so, which types of green space matter?

METHOD

Multilevel discrete time-to-event cohort study of incident Alzheimer's disease over 11 years among a baseline recruited between January 1, 2006 and December 31, 2009 (the Sax Institute's 45 and Up Study). Sampled participants for this study (N=109,688) were aged 45 years or older with no record of dementia up to 6 years before baseline, living in the cities of Sydney, Wollongong and Newcastle, Australia. Exposures were percentage total green space, tree canopy and open grass within 1.6-km road network distance buffers at baseline. Outcomes were time-to-first anti-dementia medication prescription (Department of Human Services) or dementia detected during hospitalisation or death up to 31 December 2016 (up to 11 years follow-up). Outcomes were analysed in parallel to triangulate on associations with green space, while testing for bias due to potential under-prescribing of anti-dementia medications. Models were adjusted for baseline person-level factors and area-level socioeconomic disadvantage.

RESULTS

Dementia detection varied by case ascertainment method. 1.55% (1,703/109,688) persons were detected using prescribed anti-dementia medications. 3.32% (3,639/109,688) persons were detected during hospitalisation or death via ICD-10 codes. Dementia incidence irrespective of outcome measurement was lower among females, younger participants, those living in couples, with higher qualifications and higher incomes. Dementia risk was lower with more tree canopy when the outcome was measured using hospital and death records (≥30% vs <10% tree canopy incidence hazard ratio (IHR) = 0.86, 95%CI 0.75, 0.99), after adjusting for person-level factors. The opposite association was observed when anti-dementia medications were used to detect dementia (≥30% vs <10% tree canopy IHR = 1.33, 95%CI 1.07, 1.66). Anti-dementia medication-based detection also indicated lower dementia risk with more open grass (≥20% vs <5% IHR = 0.83, 95%CI 0.67, 1.03). Anti-dementia medication prescribing was lower in the highest vs. lowest area-level disadvantage tertile (29.8% vs. 43.7%) among people diagnosed with dementia, indicating potential bias from geographic differences in prescribing practices. Adjusting for area-level disadvantage explained associations between tree canopy, open grass and dementia when detected by anti-dementia medication, but had negligible impact on negative (i.e. potentially protective) association between tree canopy and dementia detected by hospital and death records (≥30% vs <10% tree canopy hazard ratio 0.84, 95%CI 0.72, 0.99).

CONCLUSIONS

Increasing urban tree canopy cover may help to reduce the risk of dementia. Replication in contrasting contexts and mediation studies to assess pathways are warranted.

Prevention of dementia in an ageing world: Evidence and biological rationale

As the population ages, the number of people with dementia is expected to increase in the coming decades, with consequences at the societal and individual levels. In this narrative review, we provide a summary of the scientific evidence concerning dementia prevention, with a focus on the following three strategies: 1) Targeting the body to protect the brain, including prevention and treatment of cardiovascular morbidity; 2) Compensatory interventions to counteract brain ageing, including education and life-long engagement in cognitively and socially stimulating activities; and 3) Lifespan health promotion, such as a physically active lifestyle, smoking cessation, and a healthy and balanced diet. Next, we consider the biological mechanisms by which these strategies may act by taking into account the main pathways implicated in the development and progression of dementia: neurodegeneration, brain resilience, vascular damage, neuroinflammation, and oxidative stress. Based on the current evidence, and in line with the declining trends of dementia incidence in high-income countries, we conclude that timely multidomain preventive actions are promising strategies to reduce the dementia epidemic worldwide. There is still a considerable gap between the epidemiological evidence and its underlying biological mechanisms. Filling this gap will be crucial to move forward in dementia prevention worldwide.

The Relationship between Physical Exercise and Cognitive Function in Korean Middle Aged and Elderly Adults without Dementia

This study investigated the association between physical exercise and cognitive function in Koreans aged 45 years or above without dementia. Data from the 2006 to 2018 Korean Longitudinal Study of Aging (KLoSA) were used. The general characteristics of the study population were investigated using analysis of variance (ANOVA). The association between total exercise time per week and cognitive function, measured based on the Mini-Mental State Examination (MMSE) scores, was investigated using the generalized estimating equation (GEE) model. Subgroup analysis was conducted based on age, educational level, and marital status. A total of 8888 participants were investigated, of which 5173 (58.2%) individuals did not exercise regularly. Among participants who did exercise, 676 (7.6%) individuals were categorized into the Q1, 1157 (13.0%) into the Q2, 908 (10.2%) into the Q3, and 974 (11.0%) into the Q4 group. The mean MMSE score was 26.81 ± 3.17. Compared to the ‘no’ exercise group, better MMSE scores were found in the Q1 (β: 0.3523, p ≤ 0.0001), the Q2 (β: 0.2011, p ≤ 0.0001), the Q3 (β: 0.4075, p ≤ 0.0001), and the Q4 groups (β: 0.3144, p ≤ 0.0001) after adjustment. The magnitude of this association was stronger in participants aged 65 years or above and in single or separated individuals. The findings of this study confirm a positive association between physical exercise and MMSE scores in the middle aged and elderly.

Fine Particulate Matter Exposure and Cerebrospinal Fluid Markers of Vascular Injury

BACKGROUND

Cerebrovascular diseases play an important role in dementia. Air pollution is associated with cardiovascular disease, with growing links to neurodegeneration. Prior studies demonstrate associations between fine particulate matter (PM2.5) and biomarkers of endothelial injury in the blood; however, no studies have evaluated these biomarkers in cerebrospinal fluid (CSF).

OBJECTIVE

We evaluate associations between short-term and long-term PM2.5 exposure with CSF vascular cell adhesion molecule-1 (VCAM-1) and e-selectin in cognitively normal and mild cognitive impairment (MCI)/Alzheimer's disease (AD) individuals.

METHODS

We collected CSF from 133 community volunteers at VA Puget Sound between 2001-2012. We assigned short-term PM2.5 from central monitors and long-term PM2.5 based on annual average exposure predictions linked to participant addresses. We performed analyses stratified by cognitive status and adjusted for key covariates with tiered models. Our primary exposure windows for the short-term and long-term analyses were 7-day and 1-year averages, respectively.

RESULTS

Among cognitively normal individuals, a 5 μg/m3 increase in 7-day and 1-year average PM2.5 was associated with elevated VCAM-1 (7-day: 35.4 (9.7, 61.1) ng/ml; 1-year: 51.8 (6.5, 97.1) ng/ml). A 5 μg/m3 increase in 1-year average PM2.5, but not 7-day average, was associated with elevated e-selectin (53.3 (11.0, 95.5) pg/ml). We found no consistent associations among MCI/AD individuals.

CONCLUSIONS

We report associations between short-term and long term PM2.5 and CSF biomarkers of vascular damage in cognitively normal adults. These results are aligned with prior research linking PM2.5 to vascular damage in other biofluids as well as emerging evidence of the role of PM2.5 in neurodegeneration.

Longitudinal Associations of US Acculturation With Cognitive Performance, Cognitive Impairment, and Dementia

US Latinos, a growing, aging population, are disproportionately burdened by cognitive decline and dementia. Identification of modifiable risk factors is needed for interventions aimed at reducing risk. Broad sociocultural context may illuminate complex etiology among culturally diverse Latinos. Among 1,418 older (≥60 years), low-socioeconomic position (SEP) Latinos (predominantly of Mexican descent) in Sacramento, California, we examined whether US acculturation was associated with cognitive performance, cognitive decline, and dementia/ cognitive impairment without dementia over a 10-year period and whether education modified the associations (Sacramento Area Latino Study on Aging, 1998-2008). Analyses used linear mixed models, competing-risk regression, and inverse probability of censoring weights for attrition. Participants with high US acculturation had better cognitive performance (0.21 fewer cognitive errors at grand-mean-centered age 70 years) than those with low acculturation after adjustment for sociodemographic factors, practice effects, and survey language. Results may have been driven by cultural language use rather than identity factors (e.g., ethnic identity, interactions). Rate of cognitive decline and risk of dementia/cognitive impairment without dementia did not differ by acculturation, regardless of education (β = 0.00 (standard error, 0.00) and hazard ratio = 0.81 (95% confidence interval: 0.49, 1.35), respectively). High US acculturation was associated with better cognitive performance among these older, low-SEP Latinos. Acculturation may benefit cognition when SEP is low. Future studies should incorporate extended longitudinal assessments among more diverse groups.

Does the Type and Timing of Educational Attainment Influence Physical Health? A Novel Application of Sequence Analysis

Nontraditional education trajectories are common, but their influence on physical health is understudied. We constructed year-by-year education trajectories for 7,501 National Longitudinal Survey of Youth 1979 participants aged 14 to 48 years (262,535 person-years of education data from 1979 to 2014). We characterized trajectory similarity using sequence analysis and used hierarchical clustering to group similar educational trajectories. Using linear regression, we predicted physical health summary scores of the participants at age 50 years from the 12-item Short-Form Survey, adjusting for available confounders, and evaluated effect modification by sex, race/ethnicity, and childhood socioeconomic status. We identified 24 unique educational sequence clusters on the basis of highest level of schooling and attendance timing. General education development credentials predicted poorer health than did high school diplomas (β = -3.07, 95% confidence interval: -4.07, -2.07), and bachelor's degrees attained at earlier ages predicted better health than the same degree attained at later ages (β = 1.66, 95% confidence interval: 0.05, 3.28). Structurally marginalized groups benefited more from some educational trajectories than did advantaged groups (e.g., Black vs. White Americans with some college; those of low vs. high childhood socioeconomic status who received an associate's or bachelor's degree). Both type and timing of educational credentials may influence physical health. Literature to date has likely underestimated the impact of educational trajectories on health.

Gender and Educational Differences in the Association between Lifestyle and Cognitive Decline over 10 Years: The Doetinchem Cohort Study

BACKGROUND

Several modifiable risk factors for cognitive decline have been identified, but whether differences by gender and educational level exist is unclear.

OBJECTIVE

The present study aims to clarify this by prospectively investigating the relationship between health and lifestyle factors and cognitive functioning in different subgroups defined by gender and educational level.

METHODS

2,347 cognitive healthy individuals (mean age = 54.8, SD = 6.8, range: 41-71; 51.8% female; 26.2% low education) from the Doetinchem Cohort Study were examined for cognitive function at baseline, and at 5- and 10-year follow-up. Health- and lifestyle factors were captured by a poly-environmental risk score labelled 'LIfestyle for BRAin Health' (LIBRA). This score consists of 12 modifiable risk and protective factors for cognitive decline and dementia, with higher scores indicating greater risk (range: -2.7 to +12.7). Heterogeneity in associations between LIBRA and decline in verbal memory, cognitive flexibility, and mental speed between males and females and individuals with different levels of education were assessed in linear mixed models.

RESULTS

Overall, higher LIBRA scores predicted faster decline in verbal memory, cognitive flexibility, and mental speed over 10 years. Higher LIBRA scores were further associated with increased risk for incident cognitive impairment (one-point increase in LIBRA: HR = 1.09, 1.04-1.14, p = 0.001). In general, these effects were similar across gender and educational level.

CONCLUSION

A composite risk score comprising unhealthy lifestyle and relatively poor health in midlife is significantly associated with a worse course of cognition 10 years later. These associations were for the most part unrelated to gender or educational differences.

Inflammation in Alzheimer's Disease: Do Sex and APOE Matter?

BACKGROUND

Alzheimer's disease (AD) disproportionately affects females with steeper cognitive decline and more neuropathology compared to males, which is exacerbated in females carrying the APOEɛ4 allele. The risk of developing AD is also higher in female APOEɛ4 carriers in earlier age groups (aged 65-75), and the progression from cognitively normal to mild cognitive impairment (MCI) and to AD may be influenced by sex. Inflammation is observed in AD and is related to aging, stress, and neuroplasticity, and although studies are scarce, sex differences are noted in inflammation.

OBJECTIVE

The objective of this study was to investigate underlying physiological inflammatory mechanisms that may help explain why there are sex differences in AD and APOEɛ4 carriers.

METHODS

We investigated, using the ADNI database, the effect of sex and APOE genotype (non-carriers or carriers of 1 and 2 APOEɛ4 alleles) and sex and diagnosis (cognitively normal (CN), MCI, AD) on CSF (N = 279) and plasma (N = 527) markers of stress and inflammation.

RESULTS

We found CSF IL-16 and IL-8 levels differed by sex and APOE genotype, as IL-16 was higher in female APOEɛ4 carriers compared to non-carriers, while the opposite pattern was observed in males with IL-8. Furthermore, females had on average higher levels of plasma CRP and ICAM1 but lower levels of CSF ICAM1, IL-8, IL-16, and IgA than males. Carrying APOEɛ4 alleles and diagnosis (MCI and AD) decreased plasma CRP in both sexes.

CONCLUSION

Sex and APOE genotype differences in CSF and plasma inflammatory biomarkers support that the underlying physiological changes during aging differ by sex and tissue origin.

Functional genomics, genetic risk profiling and cell phenotypes in neurodegenerative disease

Human genetics provides unbiased insights into the causes of human disease, which can be used to create a foundation for effective ways to more accurately diagnose patients, stratify patients for more successful clinical trials, discover and develop new therapies, and ultimately help patients choose the safest and most promising therapeutic option based on their risk profile. But the process for translating basic observations from human genetics studies into pathogenic disease mechanisms and treatments is laborious and complex, and this challenge has particularly slowed the development of interventions for neurodegenerative disease. In this review, we discuss the many steps in the process, the important considerations at each stage, and some of the latest tools and technologies that are available to help investigators translate insights from human genetics into diagnostic and therapeutic strategies that will lead to the sort of advances in clinical care that make a difference for patients.

Combining Cognitive Markers to Identify Individuals at Increased Dementia Risk: Influence of Modifying Factors and Time to Diagnosis

OBJECTIVE

We investigated the extent to which combining cognitive markers increases the predictive value for future dementia, when compared to individual markers. Furthermore, we examined whether predictivity of markers differed depending on a range of modifying factors and time to diagnosis.

METHOD

Neuropsychological assessment was performed for 2357 participants (60+ years) without dementia from the population-based Swedish National Study on Aging and Care in Kungsholmen. In the main sample analyses, the outcome was dementia at 6 years. In the time-to-diagnosis analyses, a subsample of 407 participants underwent cognitive testing 12, 6, and 3 years before diagnosis, with dementia diagnosis at the 12-year follow-up.

RESULTS

Category fluency was the strongest individual predictor of dementia 6 years before diagnosis [area under the curve (AUC) = .903]. The final model included tests of verbal fluency, episodic memory, and perceptual speed (AUC = .913); these three domains were found to be the most predictive across a range of different subgroups. Twelve years before diagnosis, pattern comparison (perceptual speed) was the strongest individual predictor (AUC = .686). However, models 12 years before diagnosis did not show significantly increased predictivity above that of the covariates.

CONCLUSIONS

This study shows that combining markers from different cognitive domains leads to increased accuracy in predicting future dementia 6 years later. Markers from the verbal fluency, episodic memory, and perceptual speed domains consistently showed high predictivity across subgroups stratified by age, sex, education, apolipoprotein E ϵ4 status, and dementia type. Predictivity increased closer to diagnosis and showed highest accuracy up to 6 years before a dementia diagnosis. (JINS, 2020, 00, 1-13).

Assessment of Lifestyle Experiences across Lifespan and Cognitive Ageing in the Indian Context

With rising numbers of elderly and dementia in developing societies, there is a need to understand factors protective against dementia. Evidence suggests that lifetime cognitive activities including education, occupation, and complex leisure activities contribute to cognitive reserve. However, these factors are understudied in India. This paper describes the validation of the Lifetime of Experiences Questionnaire (LEQ), a comprehensive measure of complex lifetime activities, to the Indian cultural context. It also examines the relationship between lifetime experiences and cognition among 52 healthy elderly and 30 dementia patients. High inter-rater (κ=0.923, p < 0.001), test-retest (ρ: 0.905 to 0.986) reliability, and internal consistency were found for LEQ-total (0.992) and sub-scores. Literate dementia patients (25) scored significantly lower mid-life (27.5 vs. 23.3), late-life (28.5 vs. 22.5) and total LEQ (83.5 vs. 20.9) scores than literate healthy group (37). LEQ scores positively correlated with global cognition, and domains of attention and memory on the Addenbrooke’s Cognitive Examination, in healthy and dementia groups. Moreover, LEQ scores correlated positively with age at onset of dementia and negatively with clinical dementia rating (CDR) scores. Our study demonstrates that lifetime activities, especially mid-life experiences, play a protective role in development of late-life dementia, and need to be advocated to preserve late-life cognition.

The effect of scalp electroacupuncture combined with Memantine in patients with vascular dementia: A retrospective study

Currently there is no effective treatment for vascular dementia (VaD). Pharmacological treatment often lead to severe complications and require drug dosage adjustment. This study investigated the effect of scalp electroacupuncture combined with Memantine in VaD. The safety and antioxidative effect of scalp electroacupuncture were also explored.A retrospective study was conducted and data of inpatients of Linyi Central Hospital with VaD between June 2017 and May 2018 were collected and sorted. The patients were divided into scalp electroacupuncture-medication (A), scalp electroacupuncture (B) and medication (control) (C) groups, in which Memantine was prescribed as medication. Cognitive function, activities of daily living and quality of life assessed by Montreal Cognitive Assessment (MoCA), Barthel index and dementia quality of life questionnaire; the contents of superoxide dismutase, lipid peroxide and nitric oxide in blood samples; and adverse reaction were compared.Data from a total of 150 patients were collected (Group A, n = 55; Group B, n = 50; Group C, n = 45). The post-treatment/follow-up Montreal Cognitive Assessment, Barthel index and dementia quality of life questionnaire scores were significantly improved in all groups compared to pre-treatment (groups A and B, P<.01; group C, P<.05). The improvements were significant for groups A vs C, B vs C (P<0.01, both), and group A vs B (P<.05). The post-treatment/follow-up levels of lipid peroxide and nitric oxide decreased significantly while superoxide dismutase increased significantly in groups A and B compared to pre-treatment (P<.01, both). The differences were significant for groups A vs C, and B vs C (P < .01, both), but not significant between groups A and B (P > .05). There were no significant adverse events occurred during the study and follow-up.In combined treatment, scalp electroacupuncture works in parallel with Memantine and significantly increase the therapeutic effect in VaD with no significant adverse events. Scalp electroacupuncture may have the potential to serve as an option or alternative treatment for VaD. Scalp electroacupuncture may alleviate VaD symptoms through its antioxidative mechanism.

Change Over Time in Caregiving Networks for Older Adults With and Without Dementia

OBJECTIVES

We provide national estimates of caregiving networks for older adults with and without dementia and examine how these networks develop over time. Most prior research has focused on primary caregivers and rarely on change over time.

METHOD

We identify a cohort of older adults continuously followed in the National Health and Aging Trends Study between 2011 and 2015 and receiving help from family members or unpaid caregivers in 2015 (n = 1,288). We examine differences by dementia status in network size, types of assistance and task sharing, and composition-differentiating between "specialist" and "generalist" caregivers helping in one versus multiple activity domains. Multinomial regression is used to estimate change over time in network task sharing and composition.

RESULTS

In 2015, older adults with dementia had larger caregiving networks involving more task sharing than those without dementia and more often relied on generalist caregivers, especially the subset assisting with medical, household, and mobility or self-care activities. Uniformly greater reliance over time on these more intensely engaged generalist caregivers chiefly accounts for larger dementia networks.

DISCUSSION

Findings lend support to the need for caregiver training on managing multiple task domains and-for dementia caregivers in particular-task-sharing skills. More generally, the design of new approaches to better support older adults and their caregivers should consider the complexity, heterogeneity, and change over time in caregiving networks.

Analysis of Benzodiazepine Prescription Practices in Elderly Appalachians with Dementia via the Appalachian Informatics Platform: Longitudinal Study

BACKGROUND

Caring for the growing dementia population with complex health care needs in West Virginia has been challenging due to its large, sizably rural-dwelling geriatric population and limited resource availability.

OBJECTIVE

This paper aims to illustrate the application of an informatics platform to drive dementia research and quality care through a preliminary study of benzodiazepine (BZD) prescription patterns and its effects on health care use by geriatric patients.

METHODS

The Maier Institute Data Mart, which contains clinical and billing data on patients aged 65 years and older (N=98,970) seen within our clinics and hospital, was created. Relevant variables were analyzed to identify BZD prescription patterns and calculate related charges and emergency department (ED) use.

RESULTS

Nearly one-third (4346/13,910, 31.24%) of patients with dementia received at least one BZD prescription, 20% more than those without dementia. More women than men received at least one BZD prescription. On average, patients with dementia and at least one BZD prescription sustained higher charges and visited the ED more often than those without one.

CONCLUSIONS

The Appalachian Informatics Platform has the potential to enhance dementia care and research through a deeper understanding of dementia, data enrichment, risk identification, and care gap analysis.

Education and Cognitive Functioning Across the Life Span

Cognitive abilities are important predictors of educational and occupational performance, socioeconomic attainment, health, and longevity. Declines in cognitive abilities are linked to impairments in older adults' everyday functions, but people differ from one another in their rates of cognitive decline over the course of adulthood and old age. Hence, identifying factors that protect against compromised late-life cognition is of great societal interest. The number of years of formal education completed by individuals is positively correlated with their cognitive function throughout adulthood and predicts lower risk of dementia late in life. These observations have led to the propositions that prolonging education might (a) affect cognitive ability and (b) attenuate aging-associated declines in cognition. We evaluate these propositions by reviewing the literature on educational attainment and cognitive aging, including recent analyses of data harmonized across multiple longitudinal cohort studies and related meta-analyses. In line with the first proposition, the evidence indicates that educational attainment has positive effects on cognitive function. We also find evidence that cognitive abilities are associated with selection into longer durations of education and that there are common factors (e.g., parental socioeconomic resources) that affect both educational attainment and cognitive development. There is likely reciprocal interplay among these factors, and among cognitive abilities, during development. Education-cognitive ability associations are apparent across the entire adult life span and across the full range of education levels, including (to some degree) tertiary education. However, contrary to the second proposition, we find that associations between education and aging-associated cognitive declines are negligible and that a threshold model of dementia can account for the association between educational attainment and late-life dementia risk. We conclude that educational attainment exerts its influences on late-life cognitive function primarily by contributing to individual differences in cognitive skills that emerge in early adulthood but persist into older age. We also note that the widespread absence of educational influences on rates of cognitive decline puts constraints on theoretical notions of cognitive aging, such as the concepts of cognitive reserve and brain maintenance. Improving the conditions that shape development during the first decades of life carries great potential for improving cognitive ability in early adulthood and for reducing public-health burdens related to cognitive aging and dementia.

Regional hyperperfusion in cognitively normal APOE ε4 allele carriers in mid-life: analysis of ASL pilot data from the PREVENT-Dementia cohort

BACKGROUND

Regional cerebral hypoperfusion is characteristic of Alzheimer's disease (AD). Previous studies report conflicting findings in cognitively normal individuals at high risk of AD. Understanding early preclinical perfusion alterations may improve understanding of AD pathogenesis and lead to new biomarkers and treatment targets.

METHODS

3T arterial spin labelling MRI scans from 162 participants in the PREVENT-Dementia cohort were analysed (cognitively normal participants aged 40-59, stratified by future dementia risk). Cerebral perfusion was compared vertex-wise according to APOE ε4 status and family history (FH). Correlations between individual perfusion, age and cognitive scores (COGNITO battery) were explored.

RESULTS

Regional hyperperfusion was found in APOE ε4+group (left cingulate and lateral frontal and parietal regions p<0.01, threshold-free cluster enhancement, TFCE) and in FH +group (left temporal and parietal regions p<0.01, TFCE). Perfusion did not correlate with cognitive test scores.

CONCLUSIONS

Regional cerebral hyperperfusion in individuals at increased risk of AD in mid-life may be a very early marker of functional brain change related to AD. Increased perfusion may reflect a functional 'compensation' mechanism, offsetting the effects of early neural damage or may itself be risk factor for accelerating spread of degenerative pathology.

Education, intelligence and Alzheimer's disease: evidence from a multivariable two-sample Mendelian randomization study

OBJECTIVES

To examine whether educational attainment and intelligence have causal effects on risk of Alzheimer's disease (AD), independently of each other.

DESIGN

Two-sample univariable and multivariable Mendelian randomization (MR) to estimate the causal effects of education on intelligence and vice versa, and the total and independent causal effects of both education and intelligence on AD risk.

PARTICIPANTS

17 008 AD cases and 37 154 controls from the International Genomics of Alzheimer's Project (IGAP) consortium.

MAIN OUTCOME MEASURE

Odds ratio (OR) of AD per standardized deviation increase in years of schooling (SD = 3.6 years) and intelligence (SD = 15 points on intelligence test).

RESULTS

There was strong evidence of a causal, bidirectional relationship between intelligence and educational attainment, with the magnitude of effect being similar in both directions [OR for intelligence on education = 0.51 SD units, 95% confidence interval (CI): 0.49, 0.54; OR for education on intelligence = 0.57 SD units, 95% CI: 0.48, 0.66]. Similar overall effects were observed for both educational attainment and intelligence on AD risk in the univariable MR analysis; with each SD increase in years of schooling and intelligence, odds of AD were, on average, 37% (95% CI: 23-49%) and 35% (95% CI: 25-43%) lower, respectively. There was little evidence from the multivariable MR analysis that educational attainment affected AD risk once intelligence was taken into account (OR = 1.15, 95% CI: 0.68-1.93), but intelligence affected AD risk independently of educational attainment to a similar magnitude observed in the univariate analysis (OR = 0.69, 95% CI: 0.44-0.88).

CONCLUSIONS

There is robust evidence for an independent, causal effect of intelligence in lowering AD risk. The causal effect of educational attainment on AD risk is likely to be mediated by intelligence.

Education and the moderating roles of age, sex, ethnicity and apolipoprotein epsilon 4 on the risk of cognitive impairment

BACKGROUND

We examined how the relationship between education and latelife cognitive impairment (defined as a Mini Mental State Examination score below 24) is influenced by age, sex, ethnicity, and Apolipoprotein E epsilon 4 (APOE*4).

METHODS

Participants were 30,785 dementia-free individuals aged 55-103 years, from 18 longitudinal cohort studies, with an average follow-up ranging between 2 and 10 years. Pooled hazard ratios were obtained from multilevel parametric survival analyses predicting cognitive impairment (CI) from education and its interactions with baseline age, sex, APOE*4 and ethnicity. In separate models, education was treated as continuous (years) and categorical, with participants assigned to one of four education completion levels: Incomplete Elementary; Elementary; Middle; and High School.

RESULTS

Compared to Elementary, Middle (HR = 0.645, P = 0.004) and High School (HR = 0.472, P < 0.001) education were related to reduced CI risk. The decreased risk of CI associated with Middle education weakened with older baseline age (HR = 1.029, P = 0.056) and was stronger in women than men (HR = 1.309, P = 0.001). The association between High School and lowered CI risk, however, was not moderated by sex or baseline age, but was stronger in Asians than Whites (HR = 1.047, P = 0.044), and significant among Asian (HR = 0.34, P < 0.001) and Black (HR = 0.382, P = 0.016), but not White, APOE*4 carriers.

CONCLUSION

High School completion may reduce risk of CI associated with advancing age and APOE*4. The observed ethnoregional differences in this effect are potentially due to variations in social, economic, and political outcomes associated with educational attainment, in combination with neurobiological and genetic differences, and warrant further study.

Vision impairment and cognitive function among urban-dwelling malaysians aged 55 years and over from the Malaysian Elders Longitudinal Research (MELoR) study

INTRODUCTION

Published literature on vision impairment and cognitive function amongst older Malaysians remains scarce. This study investigates the association between vision impairment and cognitive function in an older Malaysian population.

METHODS

Subjects aged 55 years and above from the Malaysian Elders Longitudinal Research (MELoR) study with available information on vision and Montreal Cognitive Assessment (MoCA) scores were included. Data were obtained through a home-based interview and hospital-based health check by trained researchers. Visual acuity (VA) was assessed with logMAR score with vision impairment defined as VA 6/18 or worse in the better-seeing eye. Cognition was evaluated using the MoCA-Blind scoring procedure. Those with a MoCA-Blind score of <19/22 were considered to have cognitive impairment.

RESULTS

Data was available for 1144 participants, mean (SD) age = 68.57 (±7.23) years. Vision impairment was present in 143 (12.5 %) and 758 (66.3 %) had MoCA-Blind score of <19. Subjects with vision impairment were less likely to have a MoCA-Blind score of ≥19 (16.8 % vs 36.2 %, p < 0.001). Vision impairment was associated with poorer MoCA-Blind scores after adjustments for age, gender, and ethnicity (β = 2.064; 95 % CI, -1.282 to 3.320; P = 0.003). In those who had > 6 years of education attainment, vision impairment was associated with a significant reduction of cognitive function and remained so after adjustment for age and gender (β = 1.863; 95 % CI, 1.081-3.209; P = 0.025).

CONCLUSION

Our results suggest that vision impairment correlates with cognitive decline. Therefore, maintaining good vision is an important interventional strategy for preventing cognitive decline in older adults.

The Association between Neighborhood Amenities and Cognitive Function: Role of Lifestyle Activities

Many of the modifiable risk factors for dementia are lifestyle-related, and multidomain interventions tailored to individual lifestyles are recommended to prevent cognitive decline and dementia. However, studies of the relationship between the environment and cognitive function have shown that cognitive disorders and dementia are more prevalent in rural areas than in urban areas. The purpose of this study was to clarify the role of lifestyle activities on the association between neighborhood amenities and cognitive function. Our data were measured between August 2011 and February 2012. Participants comprised 3786 older adults (mean age: 71.5 years, standard deviation (SD) = ±5.2). We categorized neighborhood amenities as institutional resources that promote cognitively beneficial activities such as physical activity. We calculated the Walk Score^® for all participants using their home address and divided them into three groups. We assessed their 12 lifestyle activities performed outdoors. Cognitive function was measured via Mini-Mental Status Exam, word list memory, attention, executive function, and processing speed. We found that participants who were more likely to report many lifestyle activities were more likely to have normal cognition, even in areas where neighborhood amenities were scarce. The clinical significance of this study is that increased lifestyle activity contributes to the prevention of cognitive decline.

A Multi-method Investigation of the Personality Correlates of Functional Ability in Older Adults

OBJECTIVES

This study evaluated the role of personality in predicting functional ability (FA) in older adults using self-report, collateral report, and performance-based measures of FA.

METHODS

Participants included older adults (N = 131) who completed a personality measure (NEO-FFI), a self-report of FA (OARS ADL), and participated in a performance-based assessment of FA (DAFS-R). In addition, each participant had a collateral complete a collateral report of FA (OARS ADL). Bivariate correlations were computed to assess how Five Factor Model traits were related to self-report, collateral, and performance-based measures of FA.

RESULTS

Neuroticism was negatively related to self-reported FA (r = - .27) and collateral-reported FA (r = - .18) and Conscientiousness was positively related to self-reported FA (r = .25). None of the traits were significantly related to the performance-based measure of FA.

CONCLUSIONS

These results suggest that personality traits can impact self-reported FA in older adults and underscore the importance of assessing FA in older adults using multiple methods, particularly performance-based measures.

CLINICAL IMPLICATIONS

Clinicians should consider how personality may impact FA in older adults and multiple methods of FA performance should be examined to better tailor recommendations.

Trends and predictions for survival and mortality in individuals with Down syndrome in Brazil: A 21-year analysis

BACKGROUND

Regional heterogeneities and sociodemographic characteristics affect mortality and population survival in Brazil. However, for individuals with Down syndrome (DS) this information remains unknown. In this study, we analysed survival and mortality rates among DS individuals in the five Brazilian geographic regions. In addition, we investigated whether there is an association between mortality and sociodemographic factors across administrative regions.

METHODS

Data between 1996 and 2016, comprising 10 028 records of deaths of individuals with DS, were collected from database records of the Department of Informatics of the Unified Health System. Data on race/ethnicity, sex, age and years of schooling were defined for the association analyses. Survival data were analysed according to the Kaplan-Meier method and Cox regression model.

RESULTS

The number of deaths among people with DS has increased in recent years. Children are more susceptible to death, especially in the first years of life. Individuals living in the northern region, Indigenous women and people with no years of schooling have higher mortality. In the Southeast and South region, for White and Yellow, survival is related to a higher level of education. Ethnic factors and years of schooling influence risk for mortality across the administrative regions.

CONCLUSIONS

These findings show that sociodemographic characteristics affect survival and are associated with the risk of mortality for people with DS. In addition, this suggests that differences in access to health services among Brazilian regions, especially in the first years of life, may affect the survival of individuals with DS.

Cognitive Impairment in Old Age

Abstract. A decline in cognitive functioning is part of physiological aging. Accelerated cognitive decline is frequently linked to pathological changes, mostly due to Alzheimer’s Disease (AD), but is present also in Mild Cognitive Impairment (MCI) which is a predictor of transition to dementia. This review aims to summarize possible preventive biological and psychological treatments in different stages of lifespan to avoid more rapid cognitive decline and prevent pathological aging. Psychophysiological approaches aim to prevent brain damage and inflammation, two factors playing probably a major role in middle and old age. Interventions on working memory and imagery, using “cognitive reserve,” are beneficial for tolerating neuropathological age-related changes. Some controversial results are outlined, suggesting explanations for the inconsistency of findings. Although clear evidence from interventional studies is lacking, it seems that multi-domain interventions should be recommended to avoid or delay cognitive decline.

Imaging the aging brain: study design and baseline findings of the SENIOR cohort

Background

Current demographic trends point towards an aging society entailing increasing occurrence and burden of neurodegenerative diseases. In this context, understanding physiological aging and its turning point into neurodegeneration is essential for the development of possible biomarkers and future therapeutics of brain disease.

Methods

The SENIOR study represents a longitudinal, observational study including cognitively healthy elderlies aged between 50 and 70 years old at the time of inclusion, being followed annually over 10 years. Our multimodal protocol includes structural, diffusion, functional, and sodium magnetic resonance imaging (MRI) at 3 T and 7 T, positron emission tomography (PET), blood samples, genetics, audiometry, and neuropsychological and neurological examinations as well as assessment of neuronal risk factors.

Results

One hundred forty-two participants (50% females) were enrolled in the SENIOR cohort with a mean age of 60 (SD 6.3) years at baseline. Baseline results with multiple regression analyses reveal that cerebral white matter lesions can be predicted by cardiovascular and cognitive risk factors and age. Cardiovascular risk factors were strongly associated with juxtacortical and periventricular lesions. Intra-subject across-test variability as a measure of neuropsychological test performance and possible cognitive marker predicts white matter volume and is significantly associated with risk profile. Division of the cohort into subjects with a higher and lower risk profile shows significant differences in intra-subject across-test variability and volumes as well as cortical thickness of brain regions of the temporal lobe. There is no difference between the lower- and higher-risk groups in amyloid load using PET data from a subset of 81 subjects.

Conclusions

We here describe the study protocol and baseline findings of the SENIOR observational study which aim is the establishment of integrated, multiparametric maps of normal aging and the identification of early biomarkers for neurodegeneration. We show that intra-subject across-test variability as a marker of neuropsychological test performance as well as age, gender, and combined risk factors influence neuronal decline as represented by decrease in brain volume, cortical thickness, and increase in white matter lesions. Baseline findings will be used as underlying basis for the further implications of aging and neuronal degeneration as well as examination of brain aging under different aspects of brain pathology versus physiological aging.

Diagnostic accuracy of the repeatable battery of the assessment of neuropsychological status update, Spanish version, in predicting Alzheimer's disease among Hispanic older adults in the United States reporting memory problems

Objectives: There are few standardized, Spanish-language diagnostic tools to help identify Hispanic persons at early stages of Alzheimer's disease (AD). This study evaluated the accuracy of the Spanish version of the Repeatable Battery for the Assessment of Neuropsychological Status-Update (RBANS) in predicting AD in older Hispanic adults in the United States reporting memory problems.Methods: We analyzed data from age, sex, and education level propensity score-matched Hispanic memory clinic patients with (n = 38) and without (n = 38) a clinical diagnosis of AD. Estimates of diagnostic accuracy included sensitivity, specificity, predictive value, and receiver operating characteristic analysis.Results: After controlling for sex and matched pairs, the Total Scale score [area under curve (AUC) = 0.7417] and the Immediate (AUC = 0.7258) and Delayed (AUC = 0.7735) Memory index scores provided better estimates of diagnostic accuracy than Language, Attention, and Visuospatial/Constructional index scores. A minus 2-standard deviation (SD) cut point enhanced the predictive probability of the Delayed Memory index score. A cut point of -1.5 SD optimized the predictive probability of the Total Scale score.Conclusions: These results suggest that optimal cutoff values for the RBANS Delayed Memory index and Total Scale scores that may help identify Hispanic patients with AD as part of a comprehensive diagnostic AD assessment.

The dynamics of biomarkers across the clinical spectrum of Alzheimer's disease

Background

Quantifying changes in the levels of biological and cognitive markers prior to the clinical presentation of Alzheimer’s disease (AD) will provide a template for understanding the underlying aetiology of the clinical syndrome and, concomitantly, for improving early diagnosis, clinical trial recruitment and treatment assessment. This study aims to characterise continuous changes of such markers and determine their rate of change and temporal order throughout the AD continuum.

Methods

The methodology is founded on the development of stochastic models to estimate the expected time to reach different clinical disease states, for different risk groups, and synchronise short-term individual biomarker data onto a disease progression timeline. Twenty-seven markers are considered, including a range of cognitive scores, cerebrospinal (CSF) and plasma fluid proteins, and brain structural and molecular imaging measures. Data from 2014 participants in the Alzheimer’s Disease Neuroimaging Initiative database is utilised.

Results

The model suggests that detectable memory dysfunction could occur up to three decades prior to the onset of dementia due to AD (ADem). This is closely followed by changes in amyloid-β CSF levels and the first cognitive decline, as assessed by sensitive measures. Hippocampal atrophy could be observed as early as the initial amyloid-β accumulation. Brain hypometabolism starts later, about 14 years before onset, along with changes in the levels of total and phosphorylated tau proteins. Loss of functional abilities occurs rapidly around ADem onset. Neurofilament light is the only protein with notable early changes in plasma levels. The rate of change varies, with CSF, memory, amyloid PET and brain structural measures exhibiting the highest rate before the onset of ADem, followed by a decline. The probability of progressing to a more severe clinical state increases almost exponentially with age. In accordance with previous studies, the presence of apolipoprotein E4 alleles and amyloid-β accumulation can be associated with an increased risk of developing the disease, but their influence depends on age and clinical state.

Conclusions

Despite the limited longitudinal data at the individual level and the high variability observed in such data, the study elucidates the link between the long asynchronous pathophysiological processes and the preclinical and clinical stages of AD.

The Role of Occupation in Explaining Cognitive Functioning in Later Life: Education and Occupational Complexity in a U.S. National Sample of Black and White Men and Women

OBJECTIVE

Positive associations between education and late-life cognition have been widely reported. This study examines whether occupational complexity mediates the relationship between education and late-life cognition, and whether the magnitude of mediation differs by race, gender, or education level.

METHODS

Data were from a population-based cohort of non-Hispanic Blacks and Whites aged ≥45 years (n = 7,357). Education was categorized as less than high school, high school, some college, and college or higher. Using linear regression, we estimated the direct effect of each successive increase in education on cognitive functioning and indirect effects via substantive complexity of work.

RESULTS

Occupational complexity significantly mediated 11%-22% of the cognitive gain associated with higher levels of education. The pattern of mediation varied between White men and all other race-gender groups: among White men, the higher the education, the greater the mediation effect by occupational complexity. Among Black men and women of both races, the higher the education, the smaller the mediation effect.

DISCUSSION

Higher levels of education may provide opportunity for intellectually engaging environments throughout adulthood in the form of complex work, which may protect late-life cognition. However, this protective effect of occupational complexity may not occur equally across race-gender subgroups.

Effects of sex, race, ethnicity, and education on online aging research participation

INTRODUCTION

This study aimed to identify the relationship of sociodemographic variables with older adults participation in an online registry for recruitment and longitudinal assessment in cognitive aging.

METHODS

Using Brain Health Registry (BHR) data, associations between sociodemographic variables (sex, race, ethnicity, education) and registry participation outcomes (task completion, willingness to participate in future studies, referral/enrollment in other studies) were examined in adults aged 55+ (N = 35,919) using logistic regression. All models included sex, race, ethnicity, education, age, and subjective memory concern.

RESULTS

Non-white race, being Latino, and lower educational attainment were associated with decreased task completion and enrollment in additional studies. Results for sex were mixed.

DISCUSSION

The findings provide novel information about engagement in online aging-related registries, and highlight a need to develop improved engagement strategies targeting underrepresented sociodemographic groups. Increasing registry diversity will allow researchers to refer more representative populations to Alzheimer's and related dementias prevention and treatment trials.

Area deprivation amplifies racial inequities in premature mortality: Analysis of 242,667 deaths in Washington State, USA 2011-15

Racial and socioeconomic inequalities in health are consistently reported, but less is known about the interplay between racial and deprivation-related inequities. We used geographically-localized data on all deaths recorded in Washington state 2011 to 2015 (n = 242,667 decedents) and multi-level regression models to examine premature (<65 years) mortality by race and neighborhood deprivation separately and in combination. White versus non-white inequities in premature mortality did not vary substantially with increasing levels of deprivation. However, most non-white races from deprived neighborhoods had odds of premature mortality between three and eight times that of more-affluent whites. These findings may reflect the compounding of disadvantage stemming from social and environmental risk factors.

Association between exposure to air pollution and thalamus volume in adults: A cross-sectional study

Background

Air pollution has been associated with cognitive function and brain volume. While most previous research has examined the association between air pollution and brain volume in cortical structures or total brain volume, less research has investigated associations between exposure to air pollution and subcortical structures, including the thalamus. Further, the few available previous studies investigating associations between air pollution and thalamic volume have shown mixed results.

Methods

In this study, we evaluated the association between PM_2.5, PM_2.5–10, PM₁₀, nitrogen dioxide, and nitrogen oxides and volume of the thalamus in adults using the UK Biobank resource, a large community-based sample, while adjusting for multiple covariates that could confound an association between air pollution and thalamic volume.

Results

In adjusted models, the left but not right thalamus volume was significantly inversely associated with PM_2.5–10, although there were no significant associations between PM_2.5, PM₁₀, nitrogen dioxide, and nitrogen oxides with either left or right thalamic volumes. In addition, interactions between age and PM_2.5–10 and PM₁₀ were inversely associated with thalamic volume, such that thalamic volume in older people appeared more vulnerable to the adverse effects of PM_2.5–10 and PM₁₀, and interactions between educational attainment and PM_2.5, nitrogen dioxide, and nitrogen oxides and between self-rated health and PM_2.5–10 were positively associated with thalamic volume, such that higher educational attainment and better self-rated health appeared protective against the adverse effects of air pollution on the thalamus.

Conclusion

These findings suggest a possible association between thalamic volume and air pollution particularly in older people and in people with comparatively low educational attainment at levels of air pollution found in the United Kingdom.

Motoric Cognitive Risk Syndrome: A Risk Factor for Cognitive Impairment and Dementia in Different Populations

Changes in gait, especially decreased gait velocity, may be a harbinger of cognitive decline in aging. Motoric cognitive risk syndrome (MCR), a pre-dementia syndrome combining slow gait and cognitive complaints, is a powerful clinical tool used to identify older adults at a high risk of developing dementia. The mean prevalence of MCR worldwide, including in a Korean cohort, was around 10%. The reported risk factors for incident MCR include older age, low education, cardiovascular disease, obesity, physical inactivity, and depression. In addition to dementia, MCR is also a risk factor for other age-related adverse conditions such as falls, disability, frailty, and mortality. The use of MCR has advantages over other pre-dementia syndromes in being much simpler to implement and requires fewer resources. Identification of mechanisms responsible for MCR may help in developing interventions to reduce the growing burden of dementia and disability worldwide.

Impact of modifiable risk factors on Alzheimer's disease: A two-sample Mendelian randomization study

With the steadily increasing prevalence of Alzheimer's disease (AD) and great difficulties encountered for AD drug development presently, much interest has been devoted to identifying modifiable risk factors to lower the risk of AD, while the causal associations between risk factors and AD remain inconclusive. The present study conducted a comprehensive evaluation of the causal associations between risk factors and AD development by taking the recent advancements of Mendelian randomization (MR). Inverse variance weighted (IVW), MR-Egger, weighted median, and weighted mode were used for complementary calculation. A total of 45 risk factors and corresponding studies were covered in the study. This two-sample MR (2SMR) analysis provided a suggestive association between genetically predicted higher years of schooling and reduced risks of AD, and each standard deviation (3.71 years) increased in years of schooling was associated with a 41% reduction in the risk of AD (IVW, OR: 0.59, 95% CI: 0.45-0.77). At the same time, it was genetically predicted that urate might be a risk factor in AD, and it was found that each standard deviation increase in urate levels (1.33 mg/dL) was associated with a 0.09-fold increase in the risk of AD (IVW, OR: 1.09, 95% CI: 1.01-1.18). To summarize, the 2SMR analysis indicated a suggestive association between genetically predicted higher years of schooling and reduced risks of AD, and between genetically predicted higher urate levels and increased risks of AD. The findings provide useful clues to help combat AD and warrants future studies.

Incidence of dementia in the oldest-old and its relationship with age: The Monzino 80-plus population-based study

INTRODUCTION

Relationship between age and dementia at extreme old ages is still an open question, yet population-based studies in this high-risk age segment are rare.

METHODS

The Monzino 80-plus is a population-based study among residents 80 years and older in the Varese province, Italy. Of 1371 eligible individuals, 1294 (94.4%), of whom 64 are centenarians, were included in the incidence study.

RESULTS

Since 2002, 584 new cases of all-cause dementia were identified over 15 years. The overall incidence rate was 7.9 per 100 person-years. Dementia risk rose with age (IRR: 1.06), with the cubic model providing the best fit (R²  = 0.91-0.96). Cumulative incidences of dementia unadjusted and adjusted for competing mortality risk progressively diverged with age.

CONCLUSION

Dementia incidence also keeps rising in nonagenarians and centenarians. Slowing down in growing risk of developing dementia with age is mainly attributable to increasing competing risk of death and resulting selective survival of individuals at lower risk of dementia.

Five Hundred Patients with Memory Loss in One Clinic in India: Does the Prevalence Vary Between Communities?

This observational study reports on the cause of memory loss in 500 consecutive patients. It confirms the previously reported finding in a smaller sample of 100 patients. There have been several publications suggesting that the prevalence of dementia is lower in certain communities but the reason is not known. This study was conducted to see if it could explain the variation between communities. Also, the observation that dementia with Lewy bodies (24.4%) outnumbers cases of Alzheimer’s disease (5.8%) has not been reported by any other investigators and needs to be verified. This finding could open a new topic of research and also help in the management of patients.

IGEMS: The Consortium on Interplay of Genes and Environment Across Multiple Studies - An Update

The Interplay of Genes and Environment across Multiple Studies (IGEMS) is a consortium of 18 twin studies from 5 different countries (Sweden, Denmark, Finland, United States, and Australia) established to explore the nature of gene-environment (GE) interplay in functioning across the adult lifespan. Fifteen of the studies are longitudinal, with follow-up as long as 59 years after baseline. The combined data from over 76,000 participants aged 14-103 at intake (including over 10,000 monozygotic and over 17,000 dizygotic twin pairs) support two primary research emphases: (1) investigation of models of GE interplay of early life adversity, and social factors at micro and macro environmental levels and with diverse outcomes, including mortality, physical functioning and psychological functioning; and (2) improved understanding of risk and protective factors for dementia by incorporating unmeasured and measured genetic factors with a wide range of exposures measured in young adulthood, midlife and later life.

Alzheimer's Disease Diagnosis and Severity Level Detection Based on Electroencephalography Modulation Spectral "Patch" Features

Over the last two decades, electroencephalography (EEG) has emerged as a reliable tool for the diagnosis of cortical disorders such as Alzheimer's disease (AD). Typically, resting-state EEG (rsEEG) signals have been used, and traditional frequency bands (delta, theta, alpha, beta and gamma) have been explored. Recent studies, however, have suggested that non-conventional bands may lead to improved diagnostic performance. In this work, we propose a new type of features derived from the 2-dimensional modulation spectral domain representation of the rsEEG signal in order to characterize the neuromodulatory deficit emergent with AD. The proposed features are computed as the power in specific "patches" or regions of interest in the power modulation spectrogram, which are shown to be highly discriminant of AD severity levels. The proposed features were compared with traditional features used in the rsEEG AD monitoring literature. Results showed the proposed features not only achieving improved performance at discriminating between healthy normal elderly controls (Nold) and AD patients with varying severity levels, but also at monitoring severity levels (i.e., mild AD versus moderate AD). Moreover, the proposed features were shown to outperform traditional rsEEG features. Finally, we validated the biological origin of the proposed features by using source localization and comparing the obtained results with ones reported in the AD literature.

Socio-economic status and dementia onset among older Japanese: A 6-year prospective cohort study from the Japan Gerontological Evaluation Study

OBJECTIVES

Lower socio-economic status (SES) may be associated with dementia later in life, but there is inconsistent evidence supporting this claim. We aim to examine the association between three SESs (education, job, and income indicators) and dementia onset in older adults.

METHODS

Study design was a 6-year prospective cohort study. Participants included a total of 52 063 community-dwelling adults aged 65 years or older without long-term care needs from the Japan Gerontological Evaluation Study. Outcome variable was dementia onset. Explanatory variables were educational years, the longest job held, and equivalised household income. We performed Cox proportional hazard analysis by gender with multiple imputation.

RESULTS

During the follow-up period, 10.5% of participants acquired dementia. The adjusted risks of dementia incidence of the participants with less than 6 years of education were 1.34 times (95% confidence interval [CI], 1.04-1.73) in men and 1.21 (1.00-1.45) times in women higher than those with more than 13 years of education. Females with less than 1.99 million yen (hazard ratio = 0.83, 0.72-0.96) of equivalised income were less likely to acquire dementia than those with four million yen or higher.

CONCLUSIONS

Educational attainment had a robust impact on dementia onset compared with the other SES factors in both genders of older Japanese people. Securing an education for children could be crucial to prevent dementia later in life. The longest job held was less likely to be risks of dementia incidence, compared with the other two factors.

Transcriptional Networks of Microglia in Alzheimer's Disease and Insights into Pathogenesis

Microglia, the main immune cells of the central nervous system, are increasingly implicated in Alzheimer's disease (AD). Manifold transcriptomic studies in the brain have not only highlighted microglia's role in AD pathogenesis, but also mapped crucial pathological processes and identified new therapeutic targets. An important component of many of these transcriptomic studies is the investigation of gene expression networks in AD brain, which has provided important new insights into how coordinated gene regulatory programs in microglia (and other cell types) underlie AD pathogenesis. Given the rapid technological advancements in transcriptional profiling, spanning from microarrays to single-cell RNA sequencing (scRNA-seq), tools used for mapping gene expression networks have evolved to keep pace with the unique features of each transcriptomic platform. In this article, we review the trajectory of transcriptomic network analyses in AD from brain to microglia, highlighting the corresponding methodological developments. Lastly, we discuss examples of how transcriptional network analysis provides new insights into AD mechanisms and pathogenesis.

Examining the Reserve Hypothesis in Parkinson's Disease: A Longitudinal Study

BACKGROUND

Whether reserve plays a role in Parkinson's disease (PD) patients has received less attention than in dementia and has been mainly examined in relation with cognitive function.

OBJECTIVE

To investigate whether reserve plays a role in the severity and progression of motor, cognitive, and nonmotor PD symptoms by examining whether education level (proxy of reserve) is associated with baseline performance and rate of progression.

METHODS

We used data from a longitudinal cohort of PD patients (≤5-year disease duration at baseline) annually followed up to 5 years (n = 393; 41% women; mean age = 62.3 years, standard deviation = 10.0; mean disease duration = 2.6 years, standard deviation = 1.5). We examined the relationship of education with time to reach Hoehn and Yahr stage ≥3 using Cox regression and with baseline severity and progression of motor (Movement Disorder Society-Unified Parkinson's Disease Rating Scale parts II and III, gait speed), cognitive (Mini-Mental State Examination), and nonmotor (depression, anxiety, nonmotor symptoms scale, quality of life) symptoms using mixed models.

RESULTS

Education level was not associated with age at onset or diagnosis. Compared with the low-education group, the incidence of Hoehn and Yahr ≥3.0 was 0.42 times lower (95% confidence interval, 0.22-0.82, P = 0.012) in the high-education group. Higher education was associated with better baseline motor function (P < 0.001), but not with the rate of motor decline (P > 0.15). Similar results were observed for cognition. Education was not associated with nonmotor symptoms.

CONCLUSIONS

Higher education is associated with better baseline motor/cognitive function in PD, but not with rate of decline, and with a lower risk of reaching Hoehn and Yahr ≥3 during the follow-up. Our observations are consistent with a passive reserve hypothesis for motor/cognitive symptoms. © 2019 International Parkinson and Movement Disorder Society.

Sex-specific relationship of cardiometabolic syndrome with lower cortical thickness

OBJECTIVE

To investigate whether cardiometabolic factors were associated with age-related differences in cortical thickness in relation to sex.

METHODS

In this cross-sectional study, we enrolled 1,322 cognitively normal elderly (≥65 years old) individuals (774 [58.5%] men, 548 [41.5%] women). We measured cortical thickness using a surface-based analysis. We analyzed the associations of cardiometabolic risk factors with cortical thickness using multivariate linear regression models after adjusting for possible confounders and interactions with age.

RESULT

Among women, hypertension (β = -1.119 to -0.024, p < 0.05) and diabetes mellitus (β = -0.920, p = 0.03) were independently associated with lower mean cortical thickness. In addition, there was an interaction effect between obesity (body mass index [BMI] ≥27.5 kg/m²) and age on cortical thickness in women (β = -0.324 to -0.010, p < 0.05), suggesting that age-related differences in cortical thickness were more prominent in obese women compared to women with normal weight. Moreover, low education level (<6 years) was correlated with lower mean cortical thickness (β = -0.053 to -0.046, p < 0.05). Conversely, among men, only being underweight (BMI ≤18.5 kg/m², β = -2.656 to -0.073, p < 0.05) was associated with lower cortical thickness.

CONCLUSIONS

Our findings suggest that cortical thickness is more vulnerable to cardiometabolic risk factors in women than in men. Therefore, sex-specific prevention strategies may be needed to protect against accelerated brain aging.

Cognitive impairment in patients with rheumatoid arthritis

BACKGROUND

Neurological manifestations of Rheumatoid Arthritis (RA) are usually uncommon. However, a number of recent studies have reported that the burden of cognitive impairment in RA could be significant. We sought to explore the prevalence and clinical predictors of cognitive impairment in persons with RA.

METHODS

This is a cross-sectional case-control study with patients with RA. Different trained and blinded interviewers registered clinical-epidemiological data and applied a standardized neurological assessment for each subject of the study. At baseline, functional limitations were characterized using the Health Assessment Questionnaire (HAQ). Cognitive impairment was evaluated with the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) while neuropsychiatric symptoms were investigated with the Hospital Anxiety and Depression Scale (HADS). Using a proper statistical analysis, we compared the neurological outcomes between case and controls and we determined the clinical predictors of cognitive decline.

RESULTS

A total of 210 patients with RA and 70 healthy controls were included in our study. More than two thirds of our patients were classified as cognitively impaired. The mean MMSE and MoCA scores were significantly lower in RA subjects compared to the control group (p < 0.001). Neuropshychiatric impairment was more prevalent in RA patients (59.5%) than in controls (17.1%) as well (p < 0.001). Greater functional limitations were correlated with worse MMSE, MoCA and HADS scores (p < 0.001).

CONCLUSION

The findings of this study suggest that there is evidence of cognitive impairment in adults with RA.

Marital status and cognitive impairment in the United States: evidence from the National Health and Aging Trends Study

PURPOSE

We provide population-based longitudinal evidence of marital status differences in the risk of cognitive impairment and dementia in the United States.

METHODS

Data were from the longitudinal National Health and Aging Trends Study, 2011-2018. The sample included 7508 respondents aged 65 years and older who contributed 25,897 person-year records. We estimated discrete-time hazard models to predict the risk of dementia and cognitive impairment, not dementia (CIND), as well as impairment in three major cognitive domains: memory, orientation, and executive function.

RESULTS

Relative to their married counterparts, divorced and widowed elders had higher odds of dementia and CIND, as well as higher odds of impairment in each of the cognitive domains. Never-married elders had higher odds of impairment in memory and orientation than their married counterparts but did not differ significantly in the odds of impaired executive function, dementia, or CIND. Cohabiting elders did not differ significantly from married respondents on any measure of cognitive impairment. We found no gender differences in the associations between marital status and the measures of cognitive impairment.

CONCLUSIONS

Marital status is a potentially important but overlooked social risk/protective factor for cognitive impairment. Divorced and widowed older adults are particularly vulnerable to cognitive impairment.

Making DEEP Sense of Lifestyle Risk and Resilience

To effectively promote life-long health and resilience against – for example – neurodegenerative diseases, evidence-based recommendations must acknowledge the complex multidimensionality not only of the diseases but also of personal lifestyle. In a straightforward descriptive and heuristic framework, more than 50 potential lifestyle factors cluster around diet (D), education (E), exercise (E), and purpose (P), unveiling their many relationships across domains and scales. The resulting systematics and its visualization might be a small but helpful step toward the development of more comprehensive, interdisciplinary models of lifestyle-dependent risk and resilience and a means to explain the opportunities and limitations of preventive measures to the public and other stakeholders. Most importantly, this perspective onto the subject implies that not all lifestyle factors are created equal but that there is a hierarchy of values and needs that influences the success of lifestyle-based interventions.

Association between polypharmacy and dementia - A systematic review and metaanalysis

Objective: The association between polypharmacy and dementia is controversial. This systematic review and meta-analysis aims to summarize existing literature concerning the association between polypharmacy and dementia. Methods: A systematic literature review was performed by searching the EMBASE, PubMed, Scopus and International Pharmaceutical Abstract databases using terms related to polypharmacy and dementia. A meta-analysis was performed using random effect models. Results: Seven studies were included in this meta-analysis. The included studies were of medium to high quality with a potential for publication bias. A strong association between polypharmacy and dementia was found (pooled adjusted risk ratio (aRR) = 1.30 (95% CI: 1.16-1.46), I² = 68%). Excessive polypharmacy was also strongly associated with dementia (pooled aRR = 1.52 (95% CI: 1.39-1.67), I² = 24%). Conclusion: Pooled risk estimates from this meta-analysis showed that polypharmacy was associated with dementia. Although the causality of the relationship cannot be concluded from this analysis, the finding encourages the use of multidimensional assessment tools for dementia that includes the number of medications as a component.

Associations Among Health Insurance Type, Cardiovascular Risk Factors, and the Risk of Dementia: A Prospective Cohort Study in Korea

Due to an aging population, dementia incidence has rapidly increased in South Korea, heaping psychological and economic burdens upon families and the society. This study was aimed at investigating the associations of health insurance type and cardiovascular risk factors with the risk of dementia. The study was performed using data from 15,043 participants aged 60 years and above, enrolled in the Seoul Dementia Management Project in 2008 and followed up until 2012. Factors such as demographic data, health insurance type, lifestyle factors, and cardiovascular risk factors were subjected to Cox proportional hazard regression analysis to identify their associations with dementia incidence. During the follow-up, 495 participants (3.3%) developed dementia. Medical Aid beneficiaries were associated with an increase in the risk of dementia (hazard ratio [HR] 1.77, 95% confidence interval [CI] 1.421–2.215). Upon analyzing a composite cardiovascular risk score derived from all five cardiovascular risk factors, the risk for dementia incidence in participants increased from 1.56 for the presence of three risk factors to 2.55 for that of four risk factors (HR 2.55, 95% CI 1.174–5.546), compared with those who had no risk factors. The Medical Aid beneficiaries of health insurance type and the presence of multiple cardiovascular risk factors were found to be associated with a higher risk of dementia incidence.

Early Secure Attachment as a Protective Factor Against Later Cognitive Decline and Dementia

The etiology of neurodegenerative disorders such as dementia is complex and incompletely understood. Interest in a developmental perspective to these pathologies is gaining momentum. An early supportive social environment seems to have important implications for social, affective and cognitive abilities across the lifespan. Attachment theory may help to explain the link between these early experiences and later outcomes. This theory considers early interactions between an infant and its caregiver to be crucial to shaping social behavior and emotion regulation strategies throughout adult life. Furthermore, research has demonstrated that such early attachment experiences can, potentially through epigenetic mechanisms, have profound neurobiological and cognitive consequences. Here we discuss how early attachment might influence the development of affective, cognitive, and neurobiological resources that could protect against cognitive decline and dementia. We argue that social relations, both early and late in life, are vital to ensuring cognitive and neurobiological health. The concepts of brain and cognitive reserve are crucial to understanding how environmental factors may impact cognitive decline. We examine the role that attachment might play in fostering brain and cognitive reserve in old age. Finally, we put forward the concept of affective reserve, to more directly frame the socio-affective consequences of early attachment as protectors against cognitive decline. We thereby aim to highlight that, in the study of aging, cognitive decline and dementia, it is crucial to consider the role of affective and social factors such as attachment.