Education and Cognitive Decline: An Integrative Analysis of Global Longitudinal Studies of Cognitive Aging

How does urbanization affect the cognitive function among older adults: A geospatial analysis in China

There has been a plethora of studies on urbanization and older adults, and more recent ones on how older adults adapt to this process with their cognitive competence. Yet it has been unclear about the relationship between them, like how the level and rate of urbanization affect the cognitive function among older adults. This study sourced, formed, and analyzed a set of geospatial big datasets from different sources, such as the Chinese Longitudinal Healthy Longevity Survey (CLHLS) data, and the NPP/VIIRS nighttime light (NTL) data. Results showed a generally negative linear association between the rate of urbanization and cognitive performance among older adults in China. The "U" shaped non-linear relationship between urbanization level and cognitive function, as well as the tipping point, were identified. At the same time, it should be noted that mediators such as education, physical activity, social activity, and community elderly service might be able to mitigate these negative associations. Furthermore, older adults living in eastern regions or urban areas appeared to have better cognitive function than those living in mid-western regions or rural areas in China. The findings also pointed to the importance of focusing on older adults with poor cognitive health status in rapidly urbanizing areas.

Polygenic Resilience Scores are Associated with Lower Penetrance of Schizophrenia Risk Genes, Protection Against Psychiatric and Medical Disorders, and Enhanced Mental Well-Being and Cognition

In the past decade, significant advances have been made in finding genomic risk loci for schizophrenia (SCZ). This, in turn, has enabled the search for SCZ resilience loci that mitigate the impact of SCZ risk genes. Recently, we discovered the first genomic resilience profile for SCZ, completely independent from the established risk loci for SCZ. We posited that these resilience loci protect against SCZ for those having a heighted genomic risk for SCZ. Nevertheless, our understanding of genetic resilience remains limited. It remains unclear whether resilience loci foster protection against adverse states associated with SCZ risk related to clinical, cognitive, and brain-structural phenotypes. To address this knowledge gap, we analyzed data from 487,409 participants from the UK Biobank, and found that resilience loci for SCZ afforded protection against lifetime psychiatric (schizophrenia, bipolar disorder, anxiety, and depression) and non-psychiatric medical disorders (such as asthma, cardiovascular disease, digestive disorders, metabolic disorders, and external causes of morbidity and mortality). Resilience loci also protected against self-harm behaviors, improved fluid intelligence, and larger whole-brain and brain-regional sizes. Overall, this study sheds light on the range of phenotypes that are significantly associated with resilience loci within the general population, revealing distinct patterns separate from those associated with SCZ risk loci. Our findings indicate that resilience loci may offer protection against serious psychiatric and medical outcomes, co-morbidities, and cognitive impairment. Therefore, it is conceivable that resilience loci facilitate adaptive processes linked to improved health and life expectancy.

Is 70 the new 60? A longitudinal analysis of cohort trends inintrinsic capacity in England and China

To understand how the health of older adults today compares to that of previous generations, we estimated intrinsic capacity and subdomains of cognitive, locomotor, sensory, psychological and vitality capacities in participants of the English Longitudinal Study on Ageing (ELSA) and the China Health and Retirement Longitudinal Study (CHARLS). We applied multilevel growth curve models to examine change over time and cohort trends. We found that more recent cohorts entered older ages with higher levels of capacity, and their subsequent age-related declines were somewhat compressed compared to earlier cohorts. These improvements in capacity were large, with the greatest gains being in the most recent cohorts. For example, a 68-year-old ELSA participant born in 1950 had higher capacity than a 62-year-old born just 10 years earlier. Trends were similar for men and women, and findings were generally consistent across English and Chinese cohorts.

My Parent, Myself, or My Child: Whose Education Matters Most for Trajectories of Cognitive Aging in Middle Age?

The growing body of evidence linking intergenerational education and late-life cognitive decline is almost exclusively from high-income countries, despite rapid intergenerational changes in education in low- and middle-income countries (LMICs). We used data from the Mexican Health and Aging Study (n = 8,822), a cohort study of Mexican adults aged ≥50 years (2001-2018), to evaluate whether parental education (none vs. any formal schooling), one's own education (less than primary school vs. completion of primary school), or an adult child's education (less than high school vs. completion of high school) was associated with verbal memory z scores. We used linear mixed models with inverse probability of attrition weights. Educational attainment in all 3 generations was associated with baseline verbal memory scores, independent of the prior generation's education. Lower parental (β = -0.005, 95% confidence interval: -0.009, -0.002) and respondent (β = -0.013, 95% confidence interval: -0.017, -0.010) educational level were associated with faster decline in delayed (but not immediate) verbal memory z scores. Associations between adult child's education and respondent's verbal memory decline varied by exposure specification. The educational attainment of parents and adult children may influence the cognitive aging of middle-aged and older adults in LMICs. These results have important implications given recent structural shifts in educational attainment in many LMICs.

Mild cognitive impairment in pemphigus

BACKGROUND

Pemphigus is a group of autoimmune blistering disorders that have been associated with dementia in previous studies. Mild cognitive impairment (MCI) can be the first stage of progression into dementia. The objective of the present study was to evaluate the frequency of MCI in pemphigus patients compared to a control group.

METHODS

This case-control study included 80 patients with pemphigus referred to the dermatology clinics of Shohadaye Tajrish and Loghman Hakim hospitals, Tehran, Iran, in 2021. A group of 80 individuals without pemphigus who visited the same clinics for cosmetic consultation or interventions were regarded as controls. Age, sex, marital status, and education were recorded for all participants. Disease duration, medications, and severity were noted for pemphigus patients. The Persian version of the Montreal Cognitive Assessment (MoCA) test was used to assess cognitive function.

RESULTS

MCI was significantly more frequent in pemphigus patients than in controls (55% vs. 37.5%, P = 0.026). Furthermore, the total MoCA score was significantly lower in pemphigus patients compared to controls (23.98 ± 3.77 vs. 25.21 ± 3.45, P = 0.032); however, among MoCA's different domains, only the executive functions score was significantly lower in pemphigus patients (P = 0.010). After adjustment, multivariable logistic regression analysis revealed that every 1-year higher education in patients decreased the odds of MCI by 52% (adjusted odds ratio = 0.483, 95% confidence interval 0.326; 0.715, P < 0.001).

CONCLUSIONS

The frequency of MCI was found to be significantly higher, and overall scores of the MoCA test, as well as its executive function domain, were significantly lower among pemphigus patients in this study compared to the control group. Additionally, a higher level of education was associated with decreased odds of MCI in pemphigus patients. Identifying pemphigus patients with MCI through the use of the MoCA test can facilitate early intervention, enabling them to seek help and support.

Relationship between prognostic nutritional index and post-stroke cognitive impairment

BACKGROUND

The Prognostic Nutritional Index (PNI) has been described as a useful screening tool for patient prognosis in several diseases. As a potential diagnostic index, it has attracted the interest of many physicians. However, the correlation between the PNI and post-stroke cognitive impairment (PSCI) remains unclear.

METHODS

A total of 285 patients with acute ischemic stroke were included. PNI was assessed as serum albumin (g/L) + 5× lymphocyte count (109/L) and was dichotomized according to the prespecified cut-off points 48.43 for the high and low groups. PSCI was defined as Mini-Mental State Examination (MMSE) < 27 at the 6-10 months follow-up. Multiple logistic regression and linear regression analyses were performed to examine the association between PNI and cognitive outcomes.

RESULTS

A low PNI was independently associated with PSCI after adjusting for age, sex, education, National Institutes of Health Stroke Scale (NIHSS), deep white matter hyperintensity (DWMH), and stroke history (odds ratio [OR]: 2.158; 95% confidence interval [CI]: 1.205-3.863). The PNI scores were significantly associated with MMSE and attention domain (β = 0.113, p = 0.006; β = 0.109, p = 0.041, respectively). The PNI improved the model's discrimination when added to the model with other clinical risk factors.

CONCLUSIONS

A low PNI was independently associated with the occurrence of PSCI and the PNI scores were specifically associated with the scores of global cognition and attention domain. It can be a promising and straightforward screening indicator to identify the person with impaired immune-nutritional status at higher risk of PSCI.

ENHANCE: a comparative prospective longitudinal study of cognitive outcomes after 3 years of hearing aid use in older adults

Background

With an aging population, the prevalence of hearing loss and dementia are increasing rapidly. Hearing loss is currently considered the largest potentially modifiable risk factor for dementia. The effect of hearing interventions on cognitive function should therefore be investigated, as if effective, these may be successfully implemented to modify cognitive outcomes for older adults with hearing loss.

Methods

This prospective longitudinal observational cohort study compared outcomes of a convenience sample of prospectively recruited first-time hearing aid users without dementia from an audiology center with those of community-living older adults participating in a large prospective longitudinal cohort study with/without hearing loss and/or hearing aids. All participants were assessed at baseline, 18 months, and 36 months using the same measures.

Results

Participants were 160 audiology clinic patients (48.8% female patient; mean age 73.5 years) with mild-severe hearing loss, fitted with hearing aids at baseline, and 102 participants of the Australian Imaging, Biomarkers and Lifestyle Flagship Study of Aging (AIBL) (55.9% female patient; mean age 74.5 years). 18- and 36-month outcomes of subsets of the first participants to reach these points and complete the cognition assessment to date are compared. Primary comparative analysis showed cognitive stability for the hearing aid group while the AIBL group declined on working memory, visual attention, and psychomotor function. There was a non-significant trend for decline in visual learning for the AIBL group versus no decline for the hearing aid group. The hearing aid group showed significant decline on only 1 subtest and at a significantly slower rate than for the AIBL participants (p < 0.05). When education effects on cognitive trajectory were controlled, the HA group still performed significantly better on visual attention and psychomotor function (lower educated participants only) compared to the AIBL group but not on working memory or visual learning. Physical activity had no effect on cognitive performance trajectory.

Conclusion

Hearing aid users demonstrated significantly better cognitive performance to 3 years post-fitting, suggesting that hearing intervention may delay cognitive decline/dementia onset in older adults. Further studies using appropriate measures of cognition, hearing, and device use, with longer follow-up, are required.

Does education moderate gender disparities in later-life memory function? A cross-national comparison of harmonized cognitive assessment protocols in the United States and India

INTRODUCTION

We compared gender disparities in later-life memory, overall and by education, in India and the United States (US).

METHODS

Data (N = 7443) were from harmonized cognitive assessment protocols (HCAPs) in the Longitudinal Aging Study of India-Diagnostic Assessment of Dementia (LASI-DAD; N = 4096; 2017-19) and US Health and Retirement Study HCAP (HRS-HCAP; N = 3347; 2016-17). We derived harmonized memory factors from each study using confirmatory factor analysis. We used multivariable-adjusted linear regression to compare gender disparities in memory function between countries, overall and by education.

RESULTS

In the United States, older women had better memory than older men (0.28 SD-unit difference; 95% CI: 0.22, 0.35). In India, older women had worse memory than older men (-0.15 SD-unit difference; 95% CI: -0.20, -0.10), which attenuated with increasing education and literacy.

CONCLUSION

We observed gender disparities in memory in India that were not present in the United States, and which dissipated with education and literacy.

Association Between Body Mass Index and Cognitive Function Among Older Adults in India: Findings from a Cross-Sectional Study

OBJECTIVE

The study aimed to explore the association between body mass index (BMI) and cognitive function among older adults in India.

METHODS

Cross-sectional data on 21,000 older adults aged 60 years and older from the first wave of the Longitudinal Ageing Study of India (LASI), conducted in India during 2017-18, were used. Bivariate analysis and multivariate linear regression models were applied. The cognition tests include memory, orientation, arithmetic function, executive function, and object naming.

RESULTS

The mean overall cognition score was 24.6 in the study population. Further, BMI status showed a significant and positive association with cognition. The association of underweight with poor cognition (β=-0.72; 95% CI = -0.89, -0.54) whereas overweight (β = 0.57; 95% CI = 0.39, 0.75) and obese (β = 0.97; 95% CI = 0.68, 1.26) with better cognition remained statistically significant after adjusting for sociodemographic, health-related behavior, and health covariates. The mean cognition score of female older adults was always lower than male older adults with normal BMI, irrespective of their BMI categories.

CONCLUSIONS

This study shows that an underweight BMI is associated with poor cognition in both male and female older adults. In the context of providing health care for older individuals, underweight individuals should be given more attention in India.

Predicting attrition of men with a history of violence from randomised clinical trials

Preventing dropout (attrition) from clinical trials is vital for improving study validity. Dropout is particularly important in justice-involved populations as they can be very challenging to engage and recruit in the first instance. This study identifies factors associated with dropout in a double-blind, placebo-controlled randomised control trial of a selective serotonin reuptake inhibitor (SSRI) aimed at reducing reoffending in highly impulsive men with histories of violent offending. Age, education, social support, psychiatric history, and length of previous incarceration were identified as factors that predict attrition. These findings are consistent with previous research examining variables associated with attrition in clinical trials for community and offender populations. We also explored referral source and treatment allocation as attrition predictors. Although neither significantly predicted attrition, we identified that there are discernible differences in the median time to attrition among the referral source subgroups. Understanding factors that predict treatment completion and attrition will allow researchers to identify participants for whom additional provisions may optimise retention and inform development of targeted interventions.

Depressive Symptomatology as a Predictor of Cognitive Impairment: Evidence from the Korean Longitudinal Study of Aging (KLOSA), 2006-2020

Depressive symptoms are recognized as risk factors for cognitive impairment with intricate underlying biological mechanisms. We explored the link between depressive symptoms and cognitive impairment onset; we also assessed how this association is influenced by educational levels. This study included 5843 individuals aged ≥45 years, comprising 27,908 observations from 2006 to 2020. Based on repeated measurements of each participant, we estimated the association between depressive symptoms and cognitive impairment onset after a 2-year follow-up by using generalized estimating equations. The incidence rate was 9.4% among those individuals without depressive symptoms, which was in contrast with a rate of 21.0% among those individuals experiencing depressive symptoms. The odds ratio (OR) (95% confidence interval [CI]) for the association between depressive symptoms and cognitive impairment onset in the overall sample was 1.61 (1.47-1.76). This association was more pronounced among individuals with higher educational levels. Specifically, the OR (95% CI) of the association between depressive symptoms and cognitive impairment was highest among individuals with a college education (2.60 [1.78-3.81]), and the association was lowest among individuals with elementary or no education levels (1.45 [1.28-1.63]). Our findings highlight the idea that although individuals with higher educational backgrounds exhibit a diminished risk of cognitive impairment, the detrimental impacts of depressive symptoms on cognitive performance are particularly more pronounced within this group.

Effects of Cognitive Training on Alzheimer's Disease and Related Dementias: The Moderating Role of Social Determinants of Health

Objective: We examined whether social determinants of health (SDoH) are associated with Alzheimer's disease and related dementias (ADRD) risk and the effects of cognitive training over a 20-year follow-up period. Methods: Data were obtained from 1605 participants in ACTIVE. SDoH measures were created using baseline data at the individual and neighborhood level. Incident ADRD was defined using administrative claims data (1999-2019). Cause-specific hazard models estimated associations between SDoH and claims-based diagnosed ADRD. Results: Higher scores on neighborhood and built environment were associated with lower ADRD risk. Trained participants obtained a greater degree of protection from ADRD when they had higher scores for SDoH domains associated with health care and education access. However, there were fewer significant SDoH moderation effects on cognitive training than expected. Discussion: Future work should continue to explore culturally tailored cognitive training interventions to reduce ADRD risk associated with SDoH that disproportionately affects racially diverse aging populations.

Harmonisation of later-life cognitive function across national contexts: results from the Harmonized Cognitive Assessment Protocols

BACKGROUND

The Harmonized Cognitive Assessment Protocol (HCAP) is an innovative instrument for cross-national comparisons of later-life cognitive function, yet its suitability across diverse populations is unknown. We aimed to harmonise general and domain-specific cognitive scores from HCAP studies across six countries, and evaluate reliability and criterion validity of the resulting harmonised scores.

METHODS

We statistically harmonised general and domain-specific cognitive function scores across publicly available HCAP partner studies in China, England, India, Mexico, South Africa, and the USA conducted between October, 2015 and January, 2020. Participants missing all cognitive test items in a given HCAP were excluded. We used an item banking approach that leveraged common cognitive test items across studies and tests that were unique to studies. We generated harmonised factor scores to represent a person's relative functioning on the latent factors of general cognitive function, memory, executive function, orientation, and language using confirmatory factor analysis. We evaluated the marginal reliability, or precision, of the factor scores using test information plots. Criterion validity of factor scores was assessed by regressing the scores on age, gender, and educational attainment in a multivariable analysis adjusted for these characteristics.

FINDINGS

We included 21 144 participants from the six HCAP studies of interest (11 480 women [54·3%] and 9664 [45·7%] men), with a median age of 69 years (IQR 64-76). Confirmatory factor analysis models of cognitive function in each country fit well: 31 (88·6%) of 35 models had adequate or good fit to the data (comparative fit index ≥0·90, root mean square error of approximation ≤0·08, and standardised root mean residual ≤0·08). Marginal reliability of the harmonised general cognitive function factor was high (>0·9) for 19 044 (90·1%) of 21 144 participant scores across the six countries. Marginal reliability of the harmonised factor was above 0·85 for 19 281 (91·2%) of 21 142 participant factor scores for memory, 7805 (41·0%) of 19 015 scores for executive function, 3446 (16·3%) of 21 103 scores for orientation, and 4329 (20·5%) of 21 113 scores for language. In each country, general cognitive function scores were lower with older age and higher with greater levels of educational attainment.

INTERPRETATION

We statistically harmonised cognitive function measures across six large population-based studies of cognitive ageing. These harmonised cognitive function scores empirically reflect comparable domains of cognitive function among older adults across the six countries, have high reliability, and are useful for population-based research. This work provides a foundation for international networks of researchers to make improved inferences and direct comparisons of cross-national associations of risk factors for cognitive outcomes in pooled analyses.

FUNDING

US National Institute on Aging.

Conceptualizing healthy cognitive aging: the role of time and variability

The interest in healthy cognitive aging (HCA) has increased substantially over the past decade. Researchers are interested in exploring how health can be promoted and cognitive decline mitigated when pathology is not present. Identifying the necessary strategies is crucial as the gradual accumulation of small declines can lead to negative effects on quality of life over time. However, the conceptualization of HCA is not agreed upon. In fact, authors often turn to the use of traditional pathology screeners in the context of HCA because of their clear threshold results and their wide use in the different fields. This leads to the assumption that individuals are either cognitively unhealthy and therefore may have some form of dementia or are dementia-free and cognitively healthy. We believe that this view is an overly simplistic approach to the understanding of the aging process. In this work, we explore how HCA has been defined and conceptualized within the different fields. We further discuss how time and variability are key concepts that are often missing when studying HCA and propose a definition that aims to unify the findings from the multidisciplinary research that studies HCA and simplify the translation of knowledge. Incorporating these two novel dimensions to the study of HCA has already been proposed methodologically but has yet been discussed at the conceptual level. We believe that the proposed new approach will allow the identification of individual factors that cause changes in cognitive health and will help build new cognitive health strategies and mitigate further declines.

Association between self-perceived hearing status and cognitive impairment in the older Brazilian population: a population-based study

Cognitive health plays an important role in the quality of life and autonomy of older adults. and it is influenced by hearing ability. This article aims to analyze the association between self-perceived hearing status and cognitive impairment in Brazilian older adults. This cross-sectional population-based study was conducted with 4,977 older adults who participated in ELSI Brazil 2015. The cognitive impairment status (outcome. categorized as "yes" and "no") and variable of interest (self-perceived hearing status. categorized as "good" "fair" and "poor") were obtained using a self-report method. The following domains were considered for cognition: temporal orientation. memory (short and long term). and language (recent and late). Poisson regression with robust variance estimation was used to assess the self-perceived hearing status-cognitive impairment association in the crude and adjusted analyses. Sociodemographic. lifestyle. and medical history variables were used to adjust the analyses. We found that 31.8% of the participants reported fair or poor hearing and 42% had cognitive impairment. In the adjusted analysis. older adults with poor hearing were revealed to have a stronger association with cognitive impairment than their peers with good hearing. Therefore. in older Brazilian adults. lower self-perceived hearing status is associated higher levels of cognitive impairment.

The indirect effect of cognitive reserve on the relationship between age and cognition in pathological ageing: A cross-sectional retrospective study in an unselected and consecutively enrolled sample

Cognitive reserve (CR) allows individuals to maintain cognitive functionality even in the presence of pathologies. The compensation hypothesis suggests that CR plays an indirect role between age and cognitive decline, contrasting the negative effect of ageing on cognition. We test this hypothesis in an unselected and consecutively enrolled sample of memory clinic attendees (n = 134) who completed the CR Index questionnaire and three neuropsychological tests assessing global cognition (MMSE, FAB, CDT). Participants were divided into two groups based on standard diagnostic criteria (DSM-5): those who were cognitively impaired (n = 92) and those who were preserved (n = 42). A principal component analysis was used to extract a composite measure of global cognitive functioning from the three neuropsychological tests, and mediation analysis was used to examine the relationship between CR, age and global cognitive functioning in the two groups. Results revealed that: (i) age had a significant direct negative effect on the global cognitive score in both groups; (ii) the three socio-behavioural proxies of CR together suppress the direct negative relationship between age and global cognitive score in cognitively impaired patients but not in cognitively preserved participants. This study confirms the association between CR, age and cognition and allows us to validate its role in a population with cognitive impairment and extend findings to a low-to-middle educated population. These results hold important implications for public health and wellness promotion, emphasising the beneficial role of maintaining healthy and active physical, cognitive and social lifestyles.

Global rural health disparities in Alzheimer's disease and related dementias: State of the science

INTRODUCTION

Individuals living in rural communities are at heightened risk for Alzheimer's disease and related dementias (ADRD), which parallels other persistent place-based health disparities. Identifying multiple potentially modifiable risk factors specific to rural areas that contribute to ADRD is an essential first step in understanding the complex interplay between various barriers and facilitators.

METHODS

An interdisciplinary, international group of ADRD researchers convened to address the overarching question of: "What can be done to begin minimizing the rural health disparities that contribute uniquely to ADRD?" In this state of the science appraisal, we explore what is known about the biological, behavioral, sociocultural, and environmental influences on ADRD disparities in rural settings.

RESULTS

A range of individual, interpersonal, and community factors were identified, including strengths of rural residents in facilitating healthy aging lifestyle interventions.

DISCUSSION

A location dynamics model and ADRD-focused future directions are offered for guiding rural practitioners, researchers, and policymakers in mitigating rural disparities.

HIGHLIGHTS

Rural residents face heightened Alzheimer's disease and related dementia (ADRD) risks and burdens due to health disparities. Defining the unique rural barriers and facilitators to cognitive health yields insight. The strengths and resilience of rural residents can mitigate ADRD-related challenges. A novel "location dynamics" model guides assessment of rural-specific ADRD issues.

Determinants of cognitive and brain resilience to tau pathology: a longitudinal analysis

Mechanisms of resilience against tau pathology in individuals across the Alzheimer's disease spectrum are insufficiently understood. Longitudinal data are necessary to reveal which factors relate to preserved cognition (i.e. cognitive resilience) and brain structure (i.e. brain resilience) despite abundant tau pathology, and to clarify whether these associations are cross-sectional or longitudinal. We used a longitudinal study design to investigate the role of several demographic, biological and brain structural factors in yielding cognitive and brain resilience to tau pathology as measured with PET. In this multicentre study, we included 366 amyloid-β-positive individuals with mild cognitive impairment or Alzheimer's disease dementia with baseline 18F-flortaucipir-PET and longitudinal cognitive assessments. A subset (n = 200) additionally underwent longitudinal structural MRI. We used linear mixed-effects models with global cognition and cortical thickness as dependent variables to investigate determinants of cognitive resilience and brain resilience, respectively. Models assessed whether age, sex, years of education, APOE-ε4 status, intracranial volume (and cortical thickness for cognitive resilience models) modified the association of tau pathology with cognitive decline or cortical thinning. We found that the association between higher baseline tau-PET levels (quantified in a temporal meta-region of interest) and rate of cognitive decline (measured with repeated Mini-Mental State Examination) was adversely modified by older age (Stβinteraction = -0.062, P = 0.032), higher education level (Stβinteraction = -0.072, P = 0.011) and higher intracranial volume (Stβinteraction = -0.07, P = 0.016). Younger age, higher education and greater cortical thickness were associated with better cognitive performance at baseline. Greater cortical thickness was furthermore associated with slower cognitive decline independent of tau burden. Higher education also modified the negative impact of tau-PET on cortical thinning, while older age was associated with higher baseline cortical thickness and slower rate of cortical thinning independent of tau. Our analyses revealed no (cross-sectional or longitudinal) associations for sex and APOE-ε4 status on cognition and cortical thickness. In this longitudinal study of clinically impaired individuals with underlying Alzheimer's disease neuropathological changes, we identified education as the most robust determinant of both cognitive and brain resilience against tau pathology. The observed interaction with tau burden on cognitive decline suggests that education may be protective against cognitive decline and brain atrophy at lower levels of tau pathology, with a potential depletion of resilience resources with advancing pathology. Finally, we did not find major contributions of sex to brain nor cognitive resilience, suggesting that previous links between sex and resilience might be mainly driven by cross-sectional differences.

Assessing the Global Cognition of Community-Dwelling Older Adults Using Motor and Sensory Factors: A Cross-Sectional Feasibility Study

Impairments in gait, postural stability, and sensory functions were proved to be strongly associated with severe cognitive impairment such as in dementia. However, to prevent dementia, it is necessary to detect cognitive deterioration early, which requires a deeper understanding of the connections between the aforementioned functions and global cognition. Therefore, the current study measured gait, postural, auditory, and visual functions and, using principal component analysis, explored their individual and cumulative association with global cognition. The global cognitive function of 82 older Korean males was determined using the Montreal Cognitive Assessment. The motor and sensory functions were summarized into seven independent factors using factor analysis, followed by age and education-level-adjusted linear regression model analysis. The seven factors obtained using factor analysis were gait speed, gait stability, midstance, general auditory ability, auditory recognition, overall visual ability, and postural stability. The linear regression model included years of education, gait stability, postural stability, and auditory recognition, and was able to explain more than half of the variability in cognitive score. This shows that motor and sensory parameters, which are obtainable through wearable sensors and mobile applications, could be utilized in detecting cognitive fluctuations even in the early stages of cognitive deterioration.

Harmonization of Later-Life Cognitive Function Across National Contexts: Results from the Harmonized Cognitive Assessment Protocols (HCAPs)

Background

The Harmonized Cognitive Assessment Protocol (HCAP) is an innovative instrument for cross-national comparisons of later-life cognitive function, yet its suitability across diverse populations is unknown. We aimed to harmonize general and domain-specific cognitive scores from HCAPs across six countries, and evaluate precision and criterion validity of the resulting harmonized scores.

Methods

We statistically harmonized general and domain-specific cognitive function across the six publicly available HCAP partner studies in the United States, England, India, Mexico, China, and South Africa (N=21,141). We used an item banking approach that leveraged common cognitive test items across studies and tests that were unique to studies, as identified by a multidisciplinary expert panel. We generated harmonized factor scores for general and domain- specific cognitive function using serially estimated graded-response item response theory (IRT) models. We evaluated precision of the factor scores using test information plots and criterion validity using age, gender, and educational attainment.

Findings

IRT models of cognitive function in each country fit well. We compared measurement reliability of the harmonized general cognitive function factor across each cohort using test information plots; marginal reliability was high (r> 0·90) for 93% of respondents across six countries. In each country, general cognitive function scores were lower with older ages and higher with greater levels of educational attainment.

Interpretation

We statistically harmonized cognitive function measures across six large, population-based studies of cognitive aging in the US, England, India, Mexico, China, and South Africa. Precision of the estimated scores was excellent. This work provides a foundation for international networks of researchers to make stronger inferences and direct comparisons of cross-national associations of risk factors for cognitive outcomes.

Funding

National Institute on Aging (R01 AG070953, R01 AG030153, R01 AG051125, U01 AG058499; U24 AG065182; R01AG051158).

Quantile partially linear additive model for data with dropouts and an application to modeling cognitive decline

The National Alzheimer's Coordinating Center Uniform Data Set includes test results from a battery of cognitive exams. Motivated by the need to model the cognitive ability of low-performing patients we create a composite score from ten tests and propose to model this score using a partially linear quantile regression model for longitudinal studies with non-ignorable dropouts. Quantile regression allows for modeling non-central tendencies. The partially linear model accommodates nonlinear relationships between some of the covariates and cognitive ability. The data set includes patients that leave the study prior to the conclusion. Ignoring such dropouts will result in biased estimates if the probability of dropout depends on the response. To handle this challenge, we propose a weighted quantile regression estimator where the weights are inversely proportional to the estimated probability a subject remains in the study. We prove that this weighted estimator is a consistent and efficient estimator of both linear and nonlinear effects.

Urbanicity and cognitive functioning in later life

Introduction

Prior research has shown disparities in cognitive functioning across the rural-urban continuum. We examine individual- and contextual-level factors to understand how and why urbanicity shapes cognitive functioning across older adulthood.

Methods

Using a nationally representative sample from 1996 to 2016 waves of the Health and Retirement Study (HRS) and growth curve models, we assess urban-suburban-exurban differences in older adult cognitive functioning.

Results

Results demonstrate that older adult men and women living in exurban areas, and older adult men in suburban areas, have lower cognitive functioning scores compared to their urban peers. Educational attainment and marital status contribute to but do not fully explain these differences. There were no differences in the trajectory over age, suggesting that urbanicity disparities in cognition occur earlier in life, with average differences remaining the same across older adulthood.

Discussion

Differences in cognitive functioning across urbanicity are likely due to factors accumulating prior to older adulthood.

Why Are Old-Age Disabilities Decreasing in Sweden and Denmark? Evidence on the Contribution of Cognition, Education, and Sensory Functions

OBJECTIVES

Improvements in educational attainment, cognitive and sensory functions, and a decline in the prevalence of disabilities have been observed in older adults in Sweden and Denmark. In the present study, it was investigated whether better cognition, higher educational attainment, and improved sensory function among older adults aged 60 and older in these countries have contributed to decreasing rates of old-age disabilities.

METHODS

The analyses were based on repeated cross-sectional data from the Survey of Health, Ageing, and Retirement in Europe for the 2004-2017 period. Descriptive data were used to benchmark the declining prevalence of disabilities, improving cognitive and sensory functions, and increased educational level. The association between time and disabilities was analyzed with logistic regression models, and the contribution of the improved cognitive function, education, and sensory function to the declining prevalence of old-age disabilities was estimated using the Karlson-Holm-Breen method for mediation analysis.

RESULTS

The analysis suggests that the declining prevalence of old-age disabilities in Sweden and Denmark between 2004 and 2017 can largely be attributed to improved cognitive function and vision and to a lesser extent by education and hearing ability.

DISCUSSION

These findings raise important questions about the causal mechanisms producing the associations between cognition, education, and sensory functions and disability in older age. Future studies should explore the causal nature of the associations between these mediators and old-age disabilities. In addition, they should explore whether these findings differ across regional and cultural contexts and over different time periods.

Early- to late-life environmental factors and late-life global cognition in septuagenarian and octogenarians: The SONIC study

This study aimed to evaluate cognitively stimulating environments throughout life and to examine direct and indirect associations between these environments and late-life cognition. Early-life education, three domains of work complexity (data, people, and things) based on the longest-held occupation, and engagement in late-life leisure activities (LAs) were assessed. A structural equation model was developed using cross-sectional data of 1721 Japanese older adults in 70 ± 1 and 80 ± 1 years. The model confirmed significant direct effects of work complexity with data and late-life LAs on late-life cognitive performance. The associations of education and work complexity with late-life cognition were mediated through the subsequent environment(s). However, the total effects of work complexity with people and things on late-life cognition were insignificant. The findings suggest that cognitively stimulating activities in adulthood and beyond may lead to individual differences in late-life global cognition. In addition, antecedent complex environments might make subsequent life environments more cognitively stimulating. The results are discussed from the perspectives of cognitive plasticity and environmental complexity.

Cognitive decline and dementia in women after menopause: Prevention strategies

Worldwide, cognitive decline and dementia are becoming one of the biggest challenges for public health. The decline in cognition and the development of dementia may be caused by predisposing or trigger factors. There is no consensus over whether the drop in estrogen levels after menopause is a risk factor for cognitive decline and dementia. This article discusses the prevention of cognitive decline and dementia in women after menopause, both primary prevention (essentially pharmacological intervention) and secondary prevention (chiefly diet and weight reduction). Further study is required to clarify whether menopausal hormone therapy (MHT) has a role in dementia.

The Association of Obesity and Overweight with Executive Functions in Community-Dwelling Older Women

Among the risk factors reported for cognitive decline, the literature highlights changes in body composition. Thus, the aim of the present study was to examine the relationship between obesity/overweight and executive functions in cognitively normal older adult women. This cross-sectional study included 224 individuals (60-80 years), stratified into normal weight (n = 45), overweight (n = 98), and obesity (n = 81). As outcomes, body mass index (BMI), waist circumference (WC), and Trail Making Test Parts A and B were assessed. We found positive correlations of BMI and WC with completion times of TMT-A and TMT-B, and a negative correlation of BMI and WC with education. ANCOVA showed an association between higher BMI and slower completion time of TMT-A, TMT-B, and ΔTMT (B-A). Impairment of executive functions of cognitively normal older women may be positively associated with obesity and negatively associated with years of education. The findings may contribute to designing strategies that make it possible to prevent cognitive decline in women during aging.

Effects of the Multicomponent Cognitive Training Program BrainProtect in Cognitively Healthy Adults: A Randomized Controlled Trial

BACKGROUND

Cognitive integrity is a fundamental driver of health. The exact structure of strategies against cognitive impairment is still under debate.

OBJECTIVE

To compare the short-term effects of a multicomponent cognitive training (BrainProtect) with those of general health counseling (GHC) on cognitive abilities and health-related quality of life (HRQoL) in healthy adults in Germany.

METHODS

In this parallel randomized controlled trial (RCT), 132 eligible cognitively healthy adults (age ≥50 years, Beck Depression Inventory ≤9/63; Montreal Cognitive Assessment ≥26/30) were randomized to either GHC (N = 72) or to intervention with BrainProtect (intervention group, IG; N = 60). IG participants received 8 weekly sessions of 90 min of the group-based BrainProtect program focusing on executive functions, concentration, learning, perception, and imagination, plus nutritional and physical exercise units. Before and after intervention, all participants underwent neuropsychological testing and HRQoL evaluation, blinded for pretest.

RESULTS

No significant training effect was observed for the primary endpoint of global cognition as assessed by CERAD-Plus-z Total Score (p = 0.113; ηp2 = 0.023). Improvements in several cognitive subtests were shown in the IG (N = 53) compared to the GHC (N = 62) without adverse events. Differences reached significance for verbal fluency (p = 0.021), visual memory (p = 0.013), visuo-constructive functions (p = 0.034), and HRQoL (p = 0.009). Significance was lost after adjustment, though several changes were clinically relevant.

CONCLUSION

BrainProtect did not significantly impact global cognition in this RCT. Nevertheless, the results of some outcomes indicate clinically meaningful changes, so that a strengthening of the cognitive performance by BrainProtect cannot be excluded. Further studies with larger sample size are needed to confirm these findings.

Cognitive Aging in Same- and Different-Sex Relationships: Comparing Age of Diagnosis and Rate of Cognitive Decline in the Health and Retirement Study

INTRODUCTION

The ongoing marginalization of lesbian, gay, and bisexual people has been hypothesized to produce poorer late-in-life cognitive outcomes, according to mechanisms posited by minority stress and allostatic load theories. Yet the existence of those outcomes remains understudied, and results of existing studies have been contradictory. Using a population-based longitudinal aging study, this paper will compare age at diagnosis of Alzheimer's disease (AD) or a related dementia and rates of cognitive decline between participants in same-sex relationships (SSRs) and different-sex relationships (DSRs).

METHODS

The study used longitudinal cognitive-health data from the Health and Retirement Study (HRS; 1998-2018; N = 26,344) to analyze the onset of cognitive impairment and AD/dementia and the rates of cognitive change between participants in SSRs and those in DSRs. We hypothesized that SSR participants would have worse overall cognitive functioning in old age and would experience earlier onset of cognitive impairment. Using multiple regression, we compared the ages at which participants in SSRs and DSRs first reported AD or dementia diagnoses and the ages at which they first scored below cutoffs for cognitive impairment, not dementia (CIND) and possible dementia as determined using the cognitive assessment. The study then compared rates of cognitive decline over time across the SSR and DSR groups, including stratified analyses by education, race/ethnicity, wealth, and sex/gender.

RESULTS

Participants in SSRs reported dementia diagnoses (β = -12.346; p = 0.001), crossed the threshold into CIND (β = -8.815; p < 0.001) and possible dementia (β = -13.388; p < 0.001) at a younger age than participants in DSRs. When adjusted for covariates, participants in SSRs also had lower cognition at baseline (β = 0.745; p = 0.003), though having slower rates of cognitive decline when SSR was interacted with time (β = 0.066; p = 0.003). In separate analyses, cognitive differences for SSR participants were only found in participants without undergraduate degrees, with below-median household incomes, and women.

CONCLUSION

Our findings support theories suggesting that marginalization and stigma cause premature cognitive impairment. Findings also suggest that higher education might mitigate the adverse effects of sexuality-minority status on cognitive aging. Results do not support these theories' claims of more rapid cognitive decline; the lower slopes of cognitive decline with time are compatible with the possibility of slower rates of decline for aging individuals in SSRs.

Nutritional status, alcohol-tobacco consumption behaviour and cognitive decline among older adults in India

Cognition capacity is essentially age-dependent and it is associated with the overall well-being of an individual. The public health aspects of cognitive research primarily focus on the possible delaying of cognitive decline among the older adult population. In this context, using the most recent round of the Longitudinal Ageing Study in India, 2017-2018 data, this study examines the cognition capacity among older adults aged 45 and above subject to their nutritional health and health behaviour (tobacco and alcohol consumption). It is observed that almost one in every tenth individual (10%) above 45 years of age in India shows low cognition scores. Low cognition is much more prevalent among 60 + females than males. Around one-fifth of the underweight older adults (18%) demonstrate low cognition capacity among them. Of those older adults who consume only tobacco, 11% of them demonstrate low cognition than the rest. The partial proportional odds model estimation shows that older adults are at higher risk of developing low cognition with increasing age and beyond age 65, the individuals carry a critically higher risk to experience low cognition. The estimation also shows that with increasing age older adults are higher likely to experience poor cognition independent of nutritional status, but underweight older adults are comparatively more likely to experience low cognition followed by normal and overweight older adults. In terms of alcohol-tobacco consumption behaviour, older adults who consume both are more likely to experience low cognition with increasing age followed by 'only alcohol consumers', and 'only tobacco consumers'.

Factors leading to the trajectory of cognitive decline in middle-aged and older adults using group-based trajectory modeling: A cohort study

Currently, studies exploring factors associated with the cognition at some time point and no study identifying the trajectories of cognitive changes and factors might associate with the trajectories of cognitive changes in people. This study was to identify factors associated with the trend of cognitive decline in middle-aged and older people. In this cohort study, the data of 6954 subjects were collected from China Health and Retirement Longitudinal Survey database. Group-based trajectory modeling was applied for identifying three different trajectories of cognitive function change [high initial level and slow decline group (n = 1024), moderate initial level and moderate decline group (n = 2673) and low initial level and rapid decline (LRD) group (n = 3277)]. Univariate and multivariate logistic regression analysis was conducted to identify variables influencing factors of the trajectories of cognitive function in middle-aged and older people. The follow-up interval was 2 years from 2011 to 2015, and 3 years from 2015 to 2018 via face-to-face interview. High initial level and slow decline group versus LRD group, age (OR = 2.591, 95% CI: 1.962-3.421), gender (OR = 1.398, 95% CI: 1.133-1.725), education (OR = 0.051, 95% CI: 0.039-0.068), place of residence (OR = 2.768, 95% CI: 1.663-4.606), disabled (OR = 1.557, 95% CI: 1.189-2.039), family annual income (OR = 0.757, 95% CI: 0.618-0.929), sleep duration (OR = 1.266, 95% CI: 1.023-1.567), instrumental activity of daily living impairment (OR = 2.513, 95% CI: 1.947-3.245), community activities participation (OR = 0.611, 95% CI: 0.500-0.748), depression (OR = 1.471, 95% CI: 1.185-1.828), and systolic blood pressure (OR = 1.005, 95% CI: 1.001-1.009) were factors influencing the trajectories of cognitive function. Comparing moderate initial level and moderate decline group and LRD group, age (OR = 1.245, 95% CI: 1.052-1.474), gender (OR = 1.244, 95% CI: 1.062-1.458), education (OR = 0.244, 95% CI: 0.190-0.314), marital status (OR = 1.291, 95% CI: 1.079-1.546), place of residence (OR = 1.677, 95% CI: 1.358-2.071), disability (OR = 1.396, 95% CI: 1.180-1.652), smoking (OR = 1.249, 95% CI: 1.071-1.457), family annual income (OR = 0.863, 95% CI: 0.768-0.970), sleep duration (OR = 1.215, 95% CI: 0.973-1.541), instrumental activity of daily living impairment (OR = 1.309, 95% CI: 1.098-1.560), community activities participation (OR = 0.804, 95% CI: 0.718-0.900) and depression (OR = 1.383, 95% CI: 1.217-1.571) were factors associated with the trajectories of cognitive function changes. Middle-aged and older adults who had characteristics associated with increased risk of cognitive decline might be provided with timely interventions.

Connectivity between default mode and frontoparietal networks mediates the association between global amyloid-β and episodic memory

Βeta-amyloid (Aβ) is a neurotoxic protein that deposits early in the pathogenesis of preclinical Alzheimer's disease. We aimed to identify network connectivity that may alter the negative effect of Aβ on cognition. Following assessment of memory performance, resting-state fMRI, and mean cortical PET-Aβ, a total of 364 older adults (286 with clinical dementia rating [CDR-0], 59 with CDR-0.5 and 19 with CDR-1, mean age: 74.0 ± 6.4 years) from the OASIS-3 sample were included in the analysis. Across all participants, a partial least squares regression showed that lower connectivity between posterior medial default mode and frontoparietal networks, higher within-default mode, and higher visual-motor connectivity predict better episodic memory. These connectivities partially mediate the effect of Aβ on episodic memory. These results suggest that connectivity strength between the precuneus cortex and the superior frontal gyri may alter the negative effect of Aβ on episodic memory. In contrast, education was associated with different functional connectivity patterns. In conclusion, functional characteristics of specific brain networks may help identify amyloid-positive individuals with a higher likelihood of memory decline, with implications for AD clinical trials.

Perceived ethnic discrimination and cognitive function: A 12-year longitudinal study of Mexican-origin adults

OBJECTIVES

Hispanic/Latinx adults are at increased risk for cognitive impairment, and it is critically important to identify modifiable risk factors for cognitive impairment in this population. We addressed two key questions: (1) How does perceived discrimination change across middle adulthood? And, (2) how are discrimination and the trajectory of discrimination associated with cognitive function?

METHODS

We used data from 1,110 Mexican-origin adults between 26 and 62 years old (63% female; 85% born in Mexico). Participants completed a perceived ethnic discrimination scale five times across 12 years and completed cognitive assessments in the last wave, which were composited into a measure of overall cognitive function. We used latent growth curve models to estimate the longitudinal trajectory of perceived ethnic discrimination and growth mixture models to identify sub-groups of change trajectories. We evaluated whether patterns of perceived discrimination trajectories, baseline, intermediary, and concurrent discrimination predicted cognitive function at the last wave.

RESULTS

Perceived ethnic discrimination decreased over time on average. Significant individual differences in within-person change revealed two change trajectory classes: Stable Low and High Declining. The Stable Low class had better cognitive performance compared to the High Declining class, but this effect was not robust to educational attainment. Perceived discrimination at the last wave was associated with worse cognitive function, and this effect remained after accounting for covariates.

CONCLUSIONS

This study is among the first to evaluate changes in perceived ethnic discrimination in a sample of Mexican-origin adults and their associations with cognitive function. The results highlight the need for more research to better understand the role of discrimination and other social stressors on cognitive health outcomes.

Validity and reliability of the Baecke questionnaire against accelerometer-measured physical activity in community dwelling adults according to educational level

Baecke questionnaire have been widely used to assess physical activity. However, the role of educational level on validity and reliability of Baecke questionnaire is still not stablished, being a factor that can potentially influence the accuracy of self-reported measures. The present study aimed to verify the validity and reliability of Baecke questionnaire for the measurement of physical activity in community dwelling adults according to education level. The sample included 251 adults (42.4±17.0 years, 55% of women). Physical activity was self-reported by Baecke questionnaire and objectively measured by accelerometer. The education level (EL) was classified by years of study into low (<8 years), medium (8–11 years) and high (>11 years). A 7-day test-retest reliability was analyzed by intraclass correlation coefficient. The relationship, agreement and validity of the Baecke questionnaire against accelerometry were analyzed by Spearman’s correlation, Kappa index, and ROC curve, respectively. The reliability of Baecke questionnaire were r = 0.97 (high EL), r = 0.78 (medium EL), and r = 0.68 (low EL). Sensitivity and specificity were 77% and 71% in high EL, 54% and 80% in medium EL and 33% and 89% in the low EL. Baecke questionnaire proved to be reliable and a valid measurement of habitual physical activity in adults with medium and high EL.

Analysis of risk factors for the development of cognitive dysfunction in patients with cerebral small vessel disease and the construction of a predictive model

Background

Cognitive dysfunction in cerebral small vessel disease (CSVD) is a common cause of vascular dementia. The purpose of this study was to find independent risk factors for the development of cognitive dysfunction in patients with CSVD and establish a risk prediction model, in order to provide a reference for clinical diagnosis and treatment of such patients.

Methods

In this study, clinical data of patients with CSVD admitted to the Department of Neurology in Gansu Provincial Hospital from December 2019 to December 2021 were collected, and 159 patients were finally included after strict screening according to the inclusion and exclusion criteria. There were 43 patients with normal function and 116 patients with cerebral small vessel disease cognitive impairment (CSVDCI). The logistic multivariable regression model was used to screen out the independent risk factors of cognitive dysfunction in patients with CSVD, and the nomogram of cognitive dysfunction in patients with CSVD was constructed based on the results of the logistic multivariable regression analysis. Finally, the accuracy of the prediction model was evaluated by C-index, calibration curve, receiver operating characteristic (ROC) curve, and decision curve analysis (DCA).

Results

The results of multivariable logistic regression analysis showed that hypertension (OR = 2.683, 95% CI 1.119–6.432, P = 0.027), homocysteine (Hcy) (OR = 1.083, 95% CI 1.026–1.143, P = 0.004), total CSVD MRI Score (OR = 1.593, 95% CI 1.025–2.475, P = 0.039) and years of schooling (OR = 0.883, 95% CI 0.798–0.978, P = 0.017) were independent risk factors for the development of cognitive dysfunction in patients with CSVD. The C-index of this prediction model was 0.806 (95% CI 0.735–0.877), and the calibration curve, ROC curve, and DCA curve all showed good predictive power in the nomogram.

Conclusions

The nomogram constructed in this study has high accuracy and clinical utility in predicting the occurrence of cognitive dysfunction in patients with CSVD. For patients with CSVD with the above risk factors, active clinical intervention and prevention are required during clinical consultation and disease management to avoid cognitive impairment as much as possible.

Bayesian Shared Frailty Models for Time to First Birth of Married Women in Ethiopia: Using EDHS 2016

Introduction

The primary effect of the fertility process is the birth of the first child. The ages at which women establish marital union and give their first birth depend on and result in varying demographic features. This research demonstrates how to examine the effect of numerous factors on married women's delay to first birth in Ethiopia using Bayesian parametric models with gamma shared frailty distribution.

Methods

This study analyzed data from the 2016 EDHS on factors related to the time of married women to first birth. A sample of 8810 married women from all parts of Ethiopia participated in the study. The Akaike information criterion (AIC) and Bayesian information criterion (BIC) were used to compare several parametric models with gamma shared frailty distributions to find the best model (BIC). Finally, when the prior data was taken into account, the chosen model was proven to be accurate (Bayesian approach).

Results

The median survival time for the first birth after marriage is 24 years (95% CI; 23.4, 25.3). The result shows that the place of residence, the access to media, the level of education of the mother, the education level of the husband, the use of the head of the contraceptives, and the sex of the household are statistically associated with the time to first birth of married women. The Weibull-gamma shared frailty model under the Bayesian approach was found to be the best model that fit the time to first birth data in this study. The result also showed that there is heterogeneity between regions of married women.

Conclusion

To slow the increase in the Ethiopian population, families must be taught how to use contraception, and rural populations must be educated on the necessity of increasing the length of the first birth gap rather than encouraging early marriage. In general, attempts to reduce fertility by raising the age of the first marriage must consider the social and cultural settings in which marriage takes place. On the other hand, the campaign against early marriage should focus on the sociocultural, physiological, and psychological effects, as well as the reduction of reproduction.

Protective effects of education on the cognitive decline in a mental rotation task using real models: a pilot study with middle and older aged adults

Mental rotation is the ability to rotate objects in one's mind. Large age-related decreases in accuracy and processing time are often found in studies using paper-and-pencil or computerized mental rotation tests. For older participants, these tests are often too difficult. In the present study, real models consisting of cube figures were used to assess the mental rotation performance of middle and older aged adults. It should be investigated whether these tests were comparable to paper-and-pencil or chronometric tests and if very old participants were able to solve them. Eighty-four participants (49 females) between 40 and 90 years took part and were divided into middle (40-68 years) and older aged (69-90 years) and groups with higher (with college degree) and lower education (without college degree). For accuracy, main effects of gender and age group as well as interactions of age group and education were found. Younger participants outperformed older ones only in the group with lower education. For processing time, a main effect of age group as well as an interaction of age group and education was found. The age-related cognitive decline in the higher educated group was moderate, while a large effect appeared for the group without college degree. Age and gender effects of our new test with real objects were comparable to paper-pencil and computerized tests. Furthermore, a protective effect of education on the cognitive decline in mental rotation performance is discussed.

Association of Education and Intracranial Volume With Cognitive Trajectories and Mortality Rates Across the Alzheimer Disease Continuum

Objective

To investigate relationships of education and intracranial volume (ICV) (factors related to cognitive and brain reserve, respectively) with cognitive trajectories and mortality in individuals with biomarker-defined Alzheimer disease (AD).

Methods

We selected 1,298 β-amyloid–positive memory clinic patients with subjective cognitive decline (SCD, n = 142), mild cognitive impairment (MCI, n = 274), or AD dementia (n = 882) from the Amsterdam Dementia Cohort. All participants underwent baseline MRI and neuropsychological assessment, and 68% received cognitive follow-up (median 2.3 years, interquartile range 2.4). Mortality data were collected from the Central Public Administration. In the total sample and stratified by disease stage (i.e., SCD/MCI vs dementia), we examined education and ICV as predictors of baseline and longitudinal cognitive performance on 5 cognitive domains (memory, attention, executive, language, and visuospatial functions; linear mixed models) and time to death (Cox proportional hazard models). Analyses were adjusted for age, sex, whole brain gray matter atrophy, and MRI field strength.

Results

Education and ICV showed consistent positive associations with baseline cognition across disease stages. Longitudinally, we observed a relationship between higher education and faster cognitive decline among patients with dementia on global cognition, memory, executive function, and language (range β = −0.06 to −0.13; all p < 0.05). Furthermore, in the total sample, both higher education and larger ICV were related to lower mortality risk (hazard ratio 0.84 and 0.82, respectively; p < 0.05).

Discussion

In this β-amyloid–positive memory clinic sample, both cognitive and brain reserve were positively associated with baseline cognition, whereas only education was related to longitudinal cognition (i.e., accelerated decline among more highly educated patients with dementia). Higher education and ICV both moderately attenuated overall mortality risk in AD.

Cognitive Function among World Trade Center-Exposed Community Members with Mental Health Symptoms

The World Trade Center Environmental Health Center (WTC EHC), is a federally designated clinical center of excellence for surveillance and treatment of WTC disaster exposed community members (WTC Survivors). Cognitive impairment (CI) has been extensively described in WTC responders and a concern for progressive impairment in all WTC disaster exposed groups has been raised. Cognitive status, however, has not been systematically characterized in the WTC Survivor population. We describe cognitive status in a subgroup of the Survivor population referred for mental health evaluation (N = 480) in the WTC EHC as measured by scores on the Montreal Cognitive Assessment (MoCA) instrument, and examine their association with WTC exposures and individual-level covariates including PTSD and depression screening inventory scores. In regression analyses, probable cognitive impairment (MoCA score < 26) was found in 59% of the study subjects and was significantly associated with age, race/ethnicity, education, income, depression and PTSD scores. Being caught in the dust cloud on 11 September 2011 was significantly associated with cognitive impairment even after controlling for the above. These data suggest an association with cognitive dysfunction in WTC Survivors with exposure to the toxic dust/fumes and psychological stress from the 9/11 terrorist attack and warrant further systematic study.

A comparison over 2 decades of disability-free life expectancy at age 65 years for those with long-term conditions in England: Analysis of the 2 longitudinal Cognitive Function and Ageing Studies

BACKGROUND

Previous research has examined the improvements in healthy years if different health conditions are eliminated, but often with cross-sectional data, or for a limited number of conditions. We used longitudinal data to estimate disability-free life expectancy (DFLE) trends for older people with a broad number of health conditions, identify the conditions that would result in the greatest improvement in DFLE, and describe the contribution of the underlying transitions.

METHODS AND FINDINGS

The Cognitive Function and Ageing Studies (CFAS I and II) are both large population-based studies of those aged 65 years or over in England with identical sampling strategies (CFAS I response 81.7%, N = 7,635; CFAS II response 54.7%, N = 7,762). CFAS I baseline interviews were conducted in 1991 to 1993 and CFAS II baseline interviews in 2008 to 2011, both with 2 years of follow-up. Disability was measured using the modified Townsend activities of daily living scale. Long-term conditions (LTCs-arthritis, cognitive impairment, coronary heart disease (CHD), diabetes, hearing difficulties, peripheral vascular disease (PVD), respiratory difficulties, stroke, and vision impairment) were self-reported. Multistate models estimated life expectancy (LE) and DFLE, stratified by sex and study and adjusted for age. DFLE was estimated from the transitions between disability-free and disability states at the baseline and 2-year follow-up interviews, and LE was estimated from mortality transitions up to 4.5 years after baseline. In CFAS I, 60.8% were women and average age was 75.6 years; in CFAS II, 56.1% were women and average age was 76.4 years. Cognitive impairment was the only LTC whose prevalence decreased over time (odds ratio: 0.6, 95% confidence interval (CI): 0.5 to 0.6, p < 0.001), and where the percentage of remaining years at age 65 years spent disability-free decreased for men (difference CFAS II-CFAS I: -3.6%, 95% CI: -8.2 to 1.0, p = 0.12) and women (difference CFAS II-CFAS I: -3.9%, 95% CI: -7.6 to 0.0, p = 0.04) with the LTC. For men and women with any other LTC, DFLE improved or remained similar. For women with CHD, years with disability decreased (-0.8 years, 95% CI: -3.1 to 1.6, p = 0.50) and DFLE increased (2.7 years, 95% CI: 0.7 to 4.7, p = 0.008), stemming from a reduction in the risk of incident disability (relative risk ratio: 0.6, 95% CI: 0.4 to 0.8, p = 0.004). The main limitations of the study were the self-report of health conditions and the response rate. However, inverse probability weights for baseline nonresponse and longitudinal attrition were used to ensure population representativeness.

CONCLUSIONS

In this study, we observed improvements to DFLE between 1991 and 2011 despite the presence of most health conditions we considered. Attention needs to be paid to support and care for people with cognitive impairment who had different outcomes to those with physical health conditions.

Effects of Cognitive Reserve in Alzheimer's Disease and Cognitively Unimpaired Individuals

The concept of cognitive reserve (CR) has been proposed as a protective factor that modifies the effect of brain pathology on cognitive performance. It has been characterized through CR proxies; however, they have intrinsic limitations. In this study, we utilized two different datasets containing tau, amyloid PET, and T1 magnetic resonance imaging. First, 91 Alzheimer's disease (AD) continuum subjects were included from Alzheimer's Disease Neuroimaging Initiative 3. CR was conceptualized as the residual between actual cognition and estimated cognition based on amyloid, tau, and neurodegeneration. The proposed marker was tested by the correlation with CR proxy and modulation of brain pathology effects on cognitive function. Second, longitudinal data of baseline 53 AD spectrum and 34 cognitively unimpaired (CU) participants in the MEMORI dataset were analyzed. CR marker was evaluated for the association with disease conversion rate and clinical progression. Applying our multimodal CR model, this study demonstrates the differential effect of CR on clinical progression according to the disease status and the modulating effect on the relationship between brain pathology and cognition. The proposed marker was associated with years of education and modulated the effect of pathological burden on cognitive performance in the AD spectrum. Longitudinally, higher CR marker was associated with lower disease conversion rate among prodromal AD and CU individuals. Higher CR marker was related to exacerbated cognitive decline in the AD spectrum; however, it was associated with a mitigated decline in CU individuals. These results provide evidence that CR may affect the clinical progression differentially depending on the disease status.

How Welfare Regimes Moderate the Associations Between Cognitive Aging, Education, and Occupation

OBJECTIVES

Previous studies have shown the importance of individual markers of cognitive reserve, such as education and occupation, for cognitive health in old age. However, there has been only little investigation so far on how this relationship varies across contexts.

METHODS

We analyzed data from the Survey of Health, Ageing, and Retirement in Europe, using second-order latent growth models, to assess the moderating role of welfare regimes on the relationship between education and occupation skill level in explaining overall cognitive functioning and decline in old age. Our sample includes 13 European countries using data from 5 regular waves of the survey (2004-2007 and 2011-2015) and 2 retrospective ones (2008-2009 and 2017). Cognitive functioning was modeled as a latent variable measured by immediate and delayed recall, verbal fluency, and numeracy.

RESULTS

74,193 participants were included from the survey. Our analysis showed that the association of education with cognition was weaker overall in Scandinavian countries, but stronger in Southern European countries, relative to Bismarckian ones. However, educational differences in the decline of cognition were more pronounced only in Scandinavian compared to Bismarckian countries. Additionally, higher-skilled occupations in Scandinavian countries had better overall functioning compared to the same occupations in Bismarckian countries, but there was no difference in the decline in cognitive functioning.

DISCUSSION

Our findings indicate that the associations of cognitive functioning and its decline with individuals' cognitive reserve markers (education and occupational skill level) vary according to welfare regimes, showing the importance of contextual factors in cognitive aging processes.

Trends in Dementia Prevalence, Incidence, and Mortality in the United States (2000-2016)

Objectives: The prevalence of dementia has declined in the United States; how this parallels to changes in incidence and mortality, and how improvements in educational attainment may have influences these trends, is not known. Methods: Using the Health and Retirement Study (2000-2016), we estimated logistic regression models to examine trends in dementia prevalence and incidence, and mortality for those with and without dementia. Results: The relative decline was about 2.4% per year for dementia prevalence and 1.9% for dementia incidence. Mortality declined similarly for those with and without dementia. Improved educational attainment accounted for decline in incidence, some of the decline in prevalence, and had a negligible role in mortality. Discussion: The declines in dementia incidence provide evidence that dementia prevalence should continue to decline in the near future. These declines are most likely largely driven by continued improvements in older adult education.

Cross-sectional associations of housework with cognitive, physical and sensorimotor functions in younger and older community-dwelling adults: the Yishun Study

OBJECTIVES

Regular moderate-to-vigorous intensity recreational physical activity (PA) improves physical and cognitive functions. However, the age-associated relationships between non-recreational PA and functional ability remain less explored. We examined the associations between housework and functional health among younger and older Singaporean community-dwelling adults.

DESIGN

Cross-sectional study.

SETTING AND PARTICIPANTS

Younger (<65 years, n=249) and older (≥65 years, n=240) community-dwelling adults were randomly recruited from a large residential town in Singapore.

OUTCOME MEASURES

Physical function was assessed using Short Physical Performance Battery (SPPB), repeated-chair-sit-to-stand and gait speed. Cognitive and sensorimotor functions were assessed using Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and Physiological Profile Assessment (PPA), respectively.

METHODS

Light housework (LH) and heavy housework (HH), recreational, and occupational and transport-related PAs were assessed using PA questionnaires. Participants were dichotomised into low-volume and high-volume LH and HH groups. Results were adjusted for level of recreational and other non-recreational PAs.

RESULTS

Among older but not younger adults, RBANS scores were 8% and 5% higher in high HH and LH groups compared with low HH and LH groups, respectively (p=0.012 and p=0.016). Specifically, HH was associated with 14% higher attention score (p=0.014), and LH was associated with 12% and 8% higher immediate and delayed memory scores, respectively (p<0.001 and p=0.004). In older adults, sit-to-stand time and PPA scores were 8% and 23% lower in the high HH group than the low HH group, respectively (p=0.011 and p=0.040). SPPB and gait speed did not differ with age or HH. LH was not associated with physical or sensorimotor function.

CONCLUSIONS

Among older adults, housework is associated with higher cognitive function, specifically in attention and memory. Associations of housework with physical function and sensorimotor performance were intensity dependent. Housework PA is positively associated with functional health among community-dwelling older adults, independent of recreation and other non-recreational PAs. Further longitudinal and intervention studies are needed to establish causality.

Protective factors for subjective cognitive decline individuals: trajectories and changes in a longitudinal study with Italian elderly

BACKGROUND AND PURPOSE

Many different factors have been hypothesized to modulate cognition in an aging population according to their functioning at baseline.

METHODS

This retrospective study quantifies the relative contribution of age and sex as demographic factors, comorbidity, education and occupation (classified with the International Standard Classification of Occupation 2008) as cognitive reserve proxies in accounting for cognitive aging. All participants (3081) were evaluated at baseline with a complete neuropsychological test battery (T1) and those with unimpaired profiles were classified as subjective cognitive decline, those mildly impaired as mild neurocognitive decline and those severely impaired as major neurocognitive decline. From the first assessment 543 individuals were assessed a second time (T2), and 125 a third time (T3). Depending on whether they maintained or worsened their profile, based on their initial performance, participants were then classified as resistant or declining.

RESULTS

At baseline, all individuals showed education and occupation as the best predictors of performance, in addition to age. Furthermore, across assessments, the resistant had higher levels of education and occupation than the declining. In particular, the education and occupation predicted cognitive performance in all groups considered, from the subjective cognitive decline to the one with the most severely impaired participants.

CONCLUSIONS

This study highlights the role of working activity in protecting from cognitive decline across all fragile elderly groups and even more so the individuals who are at very high risk of decline.

Status and Factors of Cognitive Function Among Older Adults in Urban China

The present study aimed to examine the current status and influencing mechanisms of different demographic factors associated with cognitive function in urban Chinese older adults. A total of 644 older adults from 14 communities in urban China (e.g., Shanghai, Beijing, and Wuxi) were investigated by using the Mini-Mental State Examination and the Repeatable Battery for the Assessment of Neuropsychological Status. The results indicated that the overall cognitive function of older adults in urban China was normal. We found an aging effect on cognitive level, and cognitive function declined more rapidly after age 80. Older age, unmarried status, and lower occupational cognitive requirements increased the likelihood of cognitive risk. Higher educational levels and active engagement in exercise may contribute to cognitive reserve and have a protective effect on cognitive decline in late life. Further study is needed to develop appropriate interventions to improve the mental health of older people.

Adherence to Mediterranean Diet and Cognitive Abilities in the Greek Cohort of Epirus Health Study

The Mediterranean diet is commonly proposed as a major modifiable protective factor that may delay cognitive impairment in the elderly. The aim of the study was to investigate the cross-sectional association of adherence to the Mediterranean diet with cognitive abilities in a younger Greek population. A total of 1201 healthy adults aged 21-77 years (mean: 47.8) from the Epirus Health Study cohort were included in the analysis. Adherence to the Mediterranean diet was measured using the 14-point Mediterranean Diet Adherence Screener (MEDAS) and cognition was measured using the Trail Making Test, the Verbal Fluency test and the Logical Memory test. Statistical analysis was performed using multiple linear regression models adjusted for age, sex, education, body mass index, smoking status, alcohol consumption and physical activity. Overall, no association was found between the MEDAS score and cognitive tests, which could be explained by the young mean age and high level of education of the participants. Future studies should target young and middle-aged individuals to gain further understanding of the association between Mediterranean diet and cognition in this age group.

A Multimodal Risk Network Predicts Executive Function Trajectories in Non-demented Aging

Background: Multiple modalities of Alzheimer's disease (AD) risk factors may operate through interacting networks to predict differential cognitive trajectories in asymptomatic aging. We test such a network in a series of three analytic steps. First, we test independent associations between three risk scores (functional-health, lifestyle-reserve, and a combined multimodal risk score) and cognitive [executive function (EF)] trajectories. Second, we test whether all three associations are moderated by the most penetrant AD genetic risk [Apolipoprotein E (APOE) ε4+ allele]. Third, we test whether a non-APOE AD genetic risk score further moderates these APOE × multimodal risk score associations. Methods: We assembled a longitudinal data set (spanning a 40-year band of aging, 53-95 years) with non-demented older adults (baseline n = 602; Mage = 70.63(8.70) years; 66% female) from the Victoria Longitudinal Study (VLS). The measures included for each modifiable risk score were: (1) functional-health [pulse pressure (PP), grip strength, and body mass index], (2) lifestyle-reserve (physical, social, cognitive-integrative, cognitive-novel activities, and education), and (3) the combination of functional-health and lifestyle-reserve risk scores. Two AD genetic risk markers included (1) APOE and (2) a combined AD-genetic risk score (AD-GRS) comprised of three single nucleotide polymorphisms (SNPs; Clusterin[rs11136000], Complement receptor 1[rs6656401], Phosphatidylinositol binding clathrin assembly protein[rs3851179]). The analytics included confirmatory factor analysis (CFA), longitudinal invariance testing, and latent growth curve modeling. Structural path analyses were deployed to test and compare prediction models for EF performance and change. Results: First, separate analyses showed that higher functional-health risk scores, lifestyle-reserve risk scores, and the combined score, predicted poorer EF performance and steeper decline. Second, APOE and AD-GRS moderated the association between functional-health risk score and the combined risk score, on EF performance and change. Specifically, only older adults in the APOEε4- group showed steeper EF decline with high risk scores on both functional-health and combined risk score. Both associations were further magnified for adults with high AD-GRS. Conclusion: The present multimodal AD risk network approach incorporated both modifiable and genetic risk scores to predict EF trajectories. The results add an additional degree of precision to risk profile calculations for asymptomatic aging populations.

The extra costs associated with a cognitive impairment: Estimates from 15 OECD countries

BACKGROUND

The objective of this study is to estimate the additional income required of a household containing an older adult member living with a cognitive impairment (CI) consistent with dementia (CID).

METHODS

Secondary analyses were provided of data from the Survey of Health Aging and Retirement in Europe incorporating data of adults' age 65 years old and older across 15 OECD countries in 2013. We also analyzed longitudinal data of a smaller subset of respondents interviewed in a previous survey wave in 2011. We used OLS regression and the Standard of Living (SOL) approach to estimating the extra costs of disability.

RESULTS

Households containing a member experiencing a CID are estimated to require 48% more income to maintain their SOL compared to similar households not including an adult with CID. Those with CI without dementia are estimated to have lower costs (14%). Those with longer-term CID are estimated to incur greater costs than those with a more recent onset of a CI. The extra costs are estimated to be lower in countries with more formalized public long-term care arrangements. We further identified out of pocket costs for home care services as a likely expenditure item driving these cost estimates.

CONCLUSIONS

Results suggest that caring for a person living with dementia can lead to considerable expenses. These additional direct costs associated with dementia provide insights for households in anticipating the risks of financial insecurity as they grow older. Future research is needed to identify the consumption items driving these estimates.

APOE E2/E2 Is Associated with Slower Rate of Cognitive Decline with Age

BACKGROUND

The E4 allele of the APOE gene is known to be associated with cognitive impairment. However, a limited number of studies have examined the association between the E2 allele and longitudinal changes of cognitive function.

OBJECTIVE

To determine whether rates of cognitive change differ in carriers of the APOE E2 allele compared to other genotypes.

METHODS

We conducted a secondary analysis of data from two ongoing longitudinal cohort studies, the Long Life Family Study (LLFS) and New England Centenarian Study (NECS). We included participants who had APOE genotyping data, data from longitudinal administrations of the Telephone Interview for Cognitive Status (TICS), and age, sex, and education available. We assessed whether cognitive change as measured by rate of decline in TICS score differed among people with different APOE genotypes. We used a hierarchical mixed effect model with APOE genotypes, their interactions with age, and potential confounders.

RESULTS

After adjusting for sex and education, in carriers of the common E3/E3 genotype, TICS score decreased by 0.15 points per year of age. In those with the E2/E2 genotype, TICS score decreased by 0.05 points per year of age, a significantly slower rate of decline (p = 0.017). We observed no protective effect of the E2/E3 genotype on cognitive decline.

CONCLUSION

These results suggest a protective effect of the E2/E2 genotype on a measure of global cognitive function.