Social enrichment on the job: Complex work with people improves episodic memory, promotes brain reserve, and reduces the risk of dementia

Association between occupational complexity and cognitive function in older adults from Brazil and Mexico

More complex occupations during adulthood may be associated with better cognition in later life. We used data from the Brazilian Longitudinal Study of Aging (ELSI) and the Mexican Health and Aging Study (MHAS) to investigate the association between occupational complexity and cognitive function. Using a regression-based approach, participants were classified as cognitively impaired or not. Occupation was categorized into four levels using the 2008 International Standard of Classification of Occupations. We used logistic regression models for separate and pooled analysis. The odds of cognitive impairment decreased with higher occupation skill levels in the ELSI, but this trend was not seen in the MHAS, where the highest skill level was not associated with cognitive impairment. ELSI participants had a lower probability of cognitive impairment compared to MHAS participants with the same occupation skill level. The results of this study suggest that programs addressing the negative consequences of lower-complexity occupations need to be tailored to specific regional contexts, considering their unique socioeconomic, cultural, and occupational landscapes.

Factors associated with cognitive reserve according to education level

INTRODUCTION

We investigated distinctive factors associated with cognitive reserve (CR) based on education level.

METHODS

Among 1247 participants who underwent neuropsychological assessment, amyloid positron emission tomography, and brain magnetic resonance imaging, 336 participants with low education (≤6 years) and 697 with high education (≥12 years) were selected. CR was measured as the difference between the predicted and observed value of cognitive function based on cortical thickness. Multiple linear regression was conducted in each group after controlling for age and sex.

RESULTS

In the low-education group, low literacy, long sleep duration(>8 h/day), and diabetes were negatively associated with CR, whereas cognitive and physical activity were positively associated with CR. In the high-education group, cognitive activity was positively related to CR, whereas low literacy, long sleep duration (> 8 h/day), and depression were negatively related to CR.

DISCUSSION

This study provides insights into different strategies for enhancing CR based on educational background.

HIGHLIGHTS

Factors associated with cognitive reserve (CR) varied according to the education level. Diabetes and physical activity were associated with CR in the low-education group. Depression was related to CR in the high-education group. Low literacy, sleep duration, and cognitive activity were associated with CR in both groups. Dementia-prevention strategies should be tailored according to educational level.

Factors Affecting Resilience and Prevention of Alzheimer's Disease and Related Dementias

Alzheimer's disease (AD) is a devastating, age-associated neurodegenerative disorder and the most common cause of dementia. The clinical continuum of AD spans from preclinical disease to subjective cognitive decline, mild cognitive impairment, and dementia stages (mild, moderate, and severe). Neuropathologically, AD is defined by the accumulation of amyloid β (Aβ) into extracellular plaques in the brain parenchyma and in the cerebral vasculature, and by abnormally phosphorylated tau that accumulates intraneuronally forming neurofibrillary tangles (NFTs). Development of treatment approaches that prevent or even reduce the cognitive decline because of AD has been slow compared to other major causes of death. Recently, the United States Food and Drug Administration gave full approval to 2 different Aβ-targeting monoclonal antibodies. However, this breakthrough disease modifying approach only applies to a limited subset of patients in the AD continuum and there are stringent eligibility criteria. Furthermore, these approaches do not prevent progression of disease, because other AD-related pathologies, such as NFTs, are not directly targeted. A non-mutually exclusive alternative is to address lifestyle interventions that can help reduce the risk of AD and AD-related dementias (ADRD). It is estimated that addressing such modifiable risk factors could potentially delay up to 40% of AD/ADRD cases. In this review, we discuss some of the many modifiable risk factors that may be associated with prevention of AD/ADRD and/or increasing brain resilience, as well as other factors that may interact with these modifiable risk factors to influence AD/ADRD progression. [Color figure can be viewed at www.annalsofneurology.org] ANN NEUROL 2024;96:633-649.

Social and general cognition are uniquely associated with social connectedness in later life

The mechanisms by which older adults maintain large, complex social networks are not well understood. Prior work has primarily focused on general cognitive ability (e.g., executive function, episodic memory), largely overlooking social cognition-the ability to process, store, and remember social information. Because social cognition plays a key role in navigating social interactions and is distinct from general cognition, we examined whether general and social cognition uniquely predicted the nature of older adults' personal social networks. Our study leveraged comprehensive measures of general cognition (executive function, episodic memory), social cognition (face memory and dynamic measures of cognitive and affective theory of mind), and a rigorous measure of personal social networks from 143 community-dwelling older adults. We found that, when modeled together and controlling for sociodemographic variables, only executive function and dynamic cognitive theory of mind positively predicted having social networks with relatively unfamiliar, loosely connected others, accounting for 17% of the unique variance in older adults' social connectedness. Interestingly, having a social network comprised primarily of close, tightly knit relationships was negatively associated with affective theory of mind performance. Findings are discussed in the context of the social-cognitive resource framework-which suggests that social cognition may be more engaged in relatively unfamiliar, versus close, interactions. Specifically, our results show that social-cognitive processes may be relatively automatic for individuals whose primary social relationships are very close but may be more strongly engaged for individuals whose interactions include at least some relatively less close relationships. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

2024 Alzheimer's disease facts and figures

This article describes the public health impact of Alzheimer's disease (AD), including prevalence and incidence, mortality and morbidity, use and costs of care and the ramifications of AD for family caregivers, the dementia workforce and society. The Special Report discusses the larger health care system for older adults with cognitive issues, focusing on the role of caregivers and non-physician health care professionals. An estimated 6.9 million Americans age 65 and older are living with Alzheimer's dementia today. This number could grow to 13.8 million by 2060, barring the development of medical breakthroughs to prevent or cure AD. Official AD death certificates recorded 119,399 deaths from AD in 2021. In 2020 and 2021, when COVID-19 entered the ranks of the top ten causes of death, Alzheimer's was the seventh-leading cause of death in the United States. Official counts for more recent years are still being compiled. Alzheimer's remains the fifth-leading cause of death among Americans age 65 and older. Between 2000 and 2021, deaths from stroke, heart disease and HIV decreased, whereas reported deaths from AD increased more than 140%. More than 11 million family members and other unpaid caregivers provided an estimated 18.4 billion hours of care to people with Alzheimer's or other dementias in 2023. These figures reflect a decline in the number of caregivers compared with a decade earlier, as well as an increase in the amount of care provided by each remaining caregiver. Unpaid dementia caregiving was valued at $346.6 billion in 2023. Its costs, however, extend to unpaid caregivers' increased risk for emotional distress and negative mental and physical health outcomes. Members of the paid health care and broader community-based workforce are involved in diagnosing, treating and caring for people with dementia. However, the United States faces growing shortages across different segments of the dementia care workforce due to a combination of factors, including the absolute increase in the number of people living with dementia. Therefore, targeted programs and care delivery models will be needed to attract, better train and effectively deploy health care and community-based workers to provide dementia care. Average per-person Medicare payments for services to beneficiaries age 65 and older with AD or other dementias are almost three times as great as payments for beneficiaries without these conditions, and Medicaid payments are more than 22 times as great. Total payments in 2024 for health care, long-term care and hospice services for people age 65 and older with dementia are estimated to be $360 billion. The Special Report investigates how caregivers of older adults with cognitive issues interact with the health care system and examines the role non-physician health care professionals play in facilitating clinical care and access to community-based services and supports. It includes surveys of caregivers and health care workers, focusing on their experiences, challenges, awareness and perceptions of dementia care navigation.

Lifetime occupational skill and later-life cognitive function among older adults in the United States, Mexico, India, and South Africa

INTRODUCTION

We conducted a cross-national comparison of the association between main lifetime occupational skills and later-life cognitive function across four economically and socially distinct countries.

METHODS

Data were from population-based studies of aging and their Harmonized Cognitive Assessment Protocols (HCAPs) in the US, South Africa, India, and Mexico (N = 10,037; Age range: 50 to 105 years; 2016 to 2020). Main lifetime occupational skill was classified according to the International Standard Classification of Occupations. Weighted, adjusted regression models estimated pooled and country-specific associations between main lifetime occupational skill and later-life general cognitive function in men and women.

RESULTS

We observed positive gradients between occupational skill and later-life cognitive function for men and women in the US and Mexico, a positive gradient for women but not men in India, and no association for men or women in South Africa.

DISCUSSION

Main lifetime occupations may be a source of later-life cognitive reserve, with cross-national heterogeneity in this association.

HIGHLIGHTS

No studies have examined cross-national differences in the association of occupational skill with cognition. We used data from Harmonized Cognitive Assessment Protocols in the US, Mexico, India, and South Africa. The association of occupational skill with cognitive function varies by country and gender.

Assessing Alzheimer's Disease Knowledge and Cognitive Risk Among a Rural Older Afro-Caribbean Cohort

PURPOSE

Older, rural Afro-Caribbeans are a growing subset of the Black population who face increased risk for Alzheimer's disease and related dementias (ADRD), but research targeting ADRD is scarce in this group. The purpose of this study was to investigate dementia risk among older Afro-Caribbeans living in a rural area. We also examined age, sex, and years of education, and knowledge about Alzheimer's disease as potential predictors of dementia risk.

DESIGN

A pre-post, correlational design was employed.

METHODS

Cognitive screenings were conducted using Nasreddine's Mini-MoCA, with tests of language fluency/orientation/recall, and linear regression analysis. A basic knowledge of Alzheimer's disease survey (BKAD) was also administered.

FINDINGS

A total of 55 Afro-Caribbean participants (67.0 +10.8y (M ± SD), 65.5% with 10y or less of education residing in a rural area within the last 20 years were included.Over 50% of the convenience sample scored in the cognitive risk range. Significant associations were found between Mini-MoCA Total and Language scores and education (p < 0.01). Further, there was a significant change from pretest to posttest in BKAD scores. BKAD pretest and posttest scores were also significantly higher for those without dementia risk based on the Mini-MoCA Total.

CONCLUSION

While the Mini-MoCA showed good reliability in less-educated older Afro-Caribbeans, scores were strongly dependent on years of education. Offering a limited intervention resulted in increased BKAD scores in this Afro-Caribbean sample, and a low BKAD score was associated with a higher dementia risk category.

CLINICAL EVIDENCE

This study contributes to the limited but growing body of research about Alzheimer's disease knowledge, cognitive risk, and dementia detection among Afro-Caribbeans. The use of language-neutral cognitive assessments is recommended among rural older immigrants.