Cognability: An Ecological Theory of neighborhoods and cognitive aging

An exploration of neighborhood characteristics, psychosocial resilience resources, and cognitive functioning among midlife and older black adults

OBJECTIVES

While existing research has shown that Black adults have worse cognitive functioning than their White counterparts, the psychosocial correlates of cognitive functioning for Black older adults are understudied. The objective of this study was to investigate the relationships among perceived neighborhood characteristics, psychosocial resilience resources, and cognitive functioning among midlife and older Black adults.

METHODS

Data were from 3,191 Black adults ages 51+ in the 2008-2016 waves of the Health and Retirement Study to examine associations among neighborhood characteristics, psychosocial resilience (sense of purpose, mastery, and social support), and cognitive functioning among Black adults. Multilevel linear regression models assessed direct effects of neighborhood characteristics and psychosocial resources on cognitive functioning. We then tested whether psychosocial resources moderated the association between neighborhood characteristics and cognitive functioning.

RESULTS

Mean levels of cognitive functioning, sense of purpose, social support, and mastery were significantly related to neighborhood disorder and discohesion. Regression results showed that levels of neighborhood disorder and high discohesion were significantly associated with cognitive functioning. Sense of purpose was positively associated with cognitive functioning, net of neighborhood characteristics. However, only social support moderated the association between neighborhood discohesion and cognition.

CONCLUSIONS

These findings demonstrate the importance of examining psychosocial and contextual risk and resilience resources among midlife and older Black adults. This work may inform the development of cognitive behavioral interventions aimed at increasing sense of purpose to promote and enhance cognitive resiliency among Black adults. Altogether, this work may have implications for policy aimed at advancing cognitive health equity.

Neighborhood Resources and Health Outcomes Among Stroke Survivors in a Population-Based Cohort

BACKGROUND

Stroke survivors believe neighborhood resources such as community centers are beneficial; however, little is known about the influence of these resources on stroke outcomes. We evaluated whether residing in neighborhoods with greater resource density is associated with favorable post-stroke outcomes.

METHODS AND RESULTS

We included Mexican American and non-Hispanic White stroke survivors from the Brain Attack Surveillance in Corpus Christi project (2009-2019). The exposure was density of neighborhood resources (eg, community centers, restaurants, stores) within a residential census tract at stroke onset. Outcomes included time to death and recurrence, and at 3 months following stroke: disability (activities of daily living/instrumental activities of daily living), cognition (Modified Mini-Mental State Exam), depression (Patient Health Questionnaire-8), and quality of life (abbreviated Stroke-Specific Quality of Life scale). We fit multivariable Cox regression and mixed linear models. We considered interactions with stroke severity, ethnicity, and sex. Among 1786 stroke survivors, median age was 64 years (interquartile range, 56-73), 55% men, and 62% Mexican American. Resource density was not associated with death, recurrence, or depression. Greater resource density (75th versus 25th percentile) was associated with more favorable cognition (Modified Mini-Mental State Exam mean difference=0.838, 95% CI=0.092, 1.584) and among moderate-severe stroke survivors, with more favorable functioning (activities of daily living/instrumental activities of daily living=-0.156 [95% CI, -0.284 to 0.027]) and quality of life (abbreviated Stroke-Specific Quality of Life scale=0.194 [95% CI, 0.029-0.359]).

CONCLUSIONS

We observed associations between greater resource density and cognition overall and with functioning and quality of life among moderate-severe stroke survivors. Further research is needed to confirm these findings and determine if neighborhood resources may be a tool for recovery.

Perceived but not objective measures of neighborhood safety and food environments are associated with longitudinal changes in processing speed among urban older adults

BACKGROUND

Although a growing body of literature documents the importance of neighborhood effects on late-life cognition, little is known about the relative strength of objective and subjective neighborhood measures on late-life cognitive changes. This study examined effects of objective and subjective neighborhood measures in three neighborhood domains (neighborhood safety, physical disorder, food environments) on longitudinal changes in processing speed, an early marker of cognitive aging and impairment.

METHODS

The analysis sample included 306 community-dwelling older adults enrolled in the Einstein Aging Study (mean age = 77, age range = 70 to 91; female = 67.7%; non-Hispanic White: 45.1%, non-Hispanic Black: 40.9%). Objective and subjective measures of neighborhood included three neighborhood domains (i.e., neighborhood safety, physical disorder, food environments). Processing speed was assessed using a brief Symbol Match task (unit: second), administered on a smartphone device six times a day for 16 days and repeated annually for up to five years. Years from baseline was used as the within-person time index.

RESULTS

Results from mixed effects models showed that subjective neighborhood safety (β= -0.028) and subjective availability of healthy foods (β= -0.028) were significantly associated with less cognitive slowing over time. When objective and subjective neighborhood measures were simultaneously examined, subjective availability of healthy foods remained significant (β= -0.028) after controlling for objective availability of healthy foods. Associations of objective neighborhood crime and physical disorder with processing speed seemed to be confounded by individual-level race and socioeconomic status; after controlling for these confounders, none of objective neighborhood measures showed significant associations with processing speed.

CONCLUSION

Subjective neighborhood safety and subjective availability of healthy foods, rather than objective measures, were associated with less cognitive slowing over time over a five-year period. Perception of one's neighborhood may be a more proximal predictor of cognitive health outcomes as it may reflect one's experiences in the environment. It would be important to improve our understanding of both objective and subjective neighborhood factors to improve cognitive health among older adults.

The Dynamic Model of Health Assets: a model development

AIM

Epidemiological research on resistance and resilience can build on models of health developed in health promotion. Nevertheless, these models need to be adjusted to approaches currently employed in epidemiology; namely, included concepts should be easy to operationalize, and links between them should be simple enough to enable statistical modeling. In addition, these models should include both individual and environmental assets. The objective of this study is to consolidate the current knowledge on health assets, adjust them to epidemiological research needs, and propose a new model of health assets for epidemiological studies on health.

DESIGN

The conceptual paper was conducted according to the guidelines for the model development.

METHODS

The development of the new model was made from the perspective of salutogenesis - the branch of health promotion studying the origins of health. The analysis of literature on health promotion, public health, and positive psychology was conducted to find the links connecting individual and environmental assets.

RESULTS

The newly developed Dynamic Model of Health Assets circularly links individual characteristics, actions, environments, and support. Each preceding component of the model contributes to the following one; each component also independently contributes to resistance and resilience. The new model may guide large-scale epidemiological research on resistance and resilience. The model's components are easy to operationalize; the model allows for constructing multilevel models and accounting for the dynamic nature of the relationships between components. It is also generic enough to be adjusted to studying contributors to resistance and resilience to different specific diseases.

CONCLUSION

The new model can guide epidemiological studies on resistance and resilience.

Dementia, dementia's risk factors and premorbid brain structure are concentrated in disadvantaged areas: National register and birth-cohort geographic analyses

INTRODUCTION

Dementia risk may be elevated in socioeconomically disadvantaged neighborhoods. Reasons for this remain unclear, and this elevation has yet to be shown at a national population level.

METHODS

We tested whether dementia was more prevalent in disadvantaged neighborhoods across the New Zealand population (N = 1.41 million analytic sample) over a 20-year observation. We then tested whether premorbid dementia risk factors and MRI-measured brain-structure antecedents were more prevalent among midlife residents of disadvantaged neighborhoods in a population-representative NZ-birth-cohort (N = 938 analytic sample).

RESULTS

People residing in disadvantaged neighborhoods were at greater risk of dementia (HR per-quintile-disadvantage-increase = 1.09, 95% confidence interval [CI]:1.08-1.10) and, decades before clinical endpoints typically emerge, evidenced elevated dementia-risk scores (CAIDE, LIBRA, Lancet, ANU-ADRI, DunedinARB; β's 0.31-0.39) and displayed dementia-associated brain structural deficits and cognitive difficulties/decline.

DISCUSSION

Disadvantaged neighborhoods have more residents with dementia, and decades before dementia is diagnosed, residents have more dementia-risk factors and brain-structure antecedents. Whether or not neighborhoods causally influence risk, they may offer scalable opportunities for primary dementia prevention.

Histories of neighborhood socioeconomic status contribute to race differences in later-life cognition

INTRODUCTION

Neighborhood characteristics are increasingly implicated in cognitive health disparities, but no research has investigated how the historical context of neighborhoods shapes these disparities.

METHODS

Four hundred sixty-four Black (55%) and White older adults (Mage = 63.6) were drawn from the Michigan Cognitive Aging Project, a community-based, prospective study of older adults. Participants' addresses at baseline (2017-2020) were geocoded and linked to 2000-2017 measures of neighborhood socioeconomic status (NSES): disadvantage [NDis] and affluence [NAff]. Latent class growth analysis (LCGA) characterized 18 interpolated year trajectories of NSES across 1344 census tracts. Path analysis examined whether NSES trajectory classes mediated the association between race and a global cognition composite.

RESULTS

LCGA identified three NDis and two NAff trajectory classes, which were associated with participant race. Only one NDis class was associated with cognition, and it mediated the association between the Black race and cognition.

DISCUSSION

Disinvestment in neighborhoods may be particularly salient in race disparities in cognitive function.

HIGHLIGHTS

Race is implicated in the likelihood of living in more disadvantaged neighborhoods. Historical trends in neighborhood disadvantage are associated with cognitive function in older adulthood. Identifying patterns of neighborhood change may inform neighborhood-level interventions.

Systematic Review of Longitudinal Evidence and Methodologies for Research on Neighborhood Characteristics and Brain Health

Objective: Synthesize longitudinal research evaluating neighborhood environments and cognition to identify methodological approaches, findings, and gaps. Methods: Included studies evaluated associations between neighborhood and cognition longitudinally among adults >45 years (or mean age of 65 years) living in developed nations. We extracted data on sample characteristics, exposures, outcomes, methods, overall findings, and assessment of disparities. Results: Forty studies met our inclusion criteria. Most (65%) measured exposure only once and a majority focused on green space and/or blue space (water), neighborhood socioeconomic status, and recreation/physical activity facilities. Similarly, over half studied incident impairment, cognitive function or decline (70%), with one examining MRI (2.5%) or Alzheimer's disease (7.5%). While most studies used repeated measures analysis to evaluate changes in the brain health outcome (51%), many studies did not account for any type of correlation within neighborhoods (35%). Less than half evaluated effect modification by race/ethnicity, socioeconomic status, and/or sex/gender. Evidence was mixed and dependent on exposure or outcome assessed. Conclusion: Although longitudinal research evaluating neighborhood and cognitive decline has expanded, gaps remain in types of exposures, outcomes, analytic approaches, and sample diversity.

Underlining neighbourhood perception: a possible risk factor for dementia that deserves more attention

This essay highlights the interplay between the neighbourhood structural environment and neighbourhood perceptions on dementia by articulating how an individual's perception of neighbourhood, with respect to their individual differences, may provide key insights to understand the link between the neighbourhood and dementia.

Neighborhood Features and Cognitive Function: Moderating Roles of Individual Socioeconomic Status

INTRODUCTION

There is an interest in exploring the associations between neighborhood characteristics and individual cognitive function; however, little is known about whether these relationships can be modified by individual socioeconomic status, such as educational attainment and income.

METHODS

Drawing from the 2010-2018 Health and Retirement Study, this study analyzed 10,621 older respondents (aged 65+) with a total of 33,931 person-waves. These respondents did not have dementia in 2010 and stayed in the same neighborhood throughout the study period. Cognitive function was measured with a 27-point indicator biennially, and neighborhood characteristics (i.e., walkability, concentrated disadvantage, and social isolation) were assessed in 2010. All analyses were performed in 2023.

RESULTS

Cognitive function is positively associated with neighborhood walkability and negatively related to concentrated disadvantage, suggesting that exposures to these neighborhood characteristics have long-lasting impacts on cognitive function. Furthermore, individual socioeconomic status modifies the relationship between neighborhood characteristics and cognitive function. Compared with those graduating from college, respondents without a bachelor's degree consistently have lower cognitive function but the educational gap in cognitive function narrows with increases in walkability (b= -0.152, SE=0.092), and widens when neighborhood concentrated disadvantage (b=0.212, SE=0.070) or social isolation (b=0.315, SE=0.125) rises. The income gap in cognitive function shrinks with increases in walkability (b= -0.063, SE=0.027).

CONCLUSIONS

The moderating role of socioeconomic status indicates that low-socioeconomic status older adults who also live in disadvantaged neighborhoods face a higher risk of poor cognitive function. Low-education and low-income aging adults may have the most to gain from investments to improve neighborhood characteristics.

A Framework for Assessing the Effects of Climate Change on Dementia Risk and Burden

Alzheimer's disease and related dementias (ADRD) represent a public health crisis poised to worsen in a changing climate. Substantial dementia burden is modifiable, attributable to risk rooted in social and environmental conditions. Climate change threatens older populations in numerous ways, but implications for cognitive aging are poorly understood. We illuminate key mechanisms by which climate change will shape incidence and lived experiences of ADRD, and propose a framework for strengthening research, clinical, and policy actions around cognitive health in the context of climate change. Direct impacts and indirect risk pathways operating through built, social, interpersonal, and biomedical systems are highlighted. Air pollution compromises brain health directly and via systemic cardiovascular and respiratory ailments. Flooding and extreme temperatures constrain health behaviors like physical activity and sleep. Medical care resulting from climate-related health shocks imposes economic and emotional tolls on people living with dementia and caregivers. Throughout, inequitable distributions of climate-exacerbated risks and adaptive resources compound existing disparities in ADRD incidence, comorbidities, and care burden. Translational research, including work prioritizing underserved communities, is crucial. A mechanistic framework can guide research questions and methods and identify clinical- and policy-level intervention loci for prevention and mitigation of climate-related impacts on ADRD risk and burden.

Effects of neighborhood built environment on cognitive function in older adults: a systematic review

BACKGROUND

In the background of an aging population, the risk of cognitive impairment in the older population is prominent. Exposure to complex neighborhood built environments may be beneficial to the cognitive health of older adults, and the purpose of this study was to systematically review the scientific evidence on the effects of neighborhood built environments on cognitive function in older adults.

METHODS

Keywords and references were searched in Web of Science, Pubmed, PsycINFO, and MEDLINE. Studies examining the relationship between the built environment and cognitive function in older adults were included. The neighborhood built environment as an independent variable was classified according to seven aspects: density, design, diversity, destination accessibility, public transportation distance, blue/green space, and built environment quality. The cognitive function as the dependent variable was classified according to overall cognitive function, domain-specific cognitive function, and incidence of dementia. The quality of the included literature was assessed using the National Institutes of Health's Observational Cohort and Cross-Sectional Study Quality Assessment Tool.

RESULTS

A total of 56 studies were included that met the inclusion criteria, including 31 cross-sectional studies, 23 longitudinal studies, 1 cross-sectional study design combined with a case-control design, and 1 longitudinal study design combined with a case-control design. Most of the studies reviewed indicate that the built environment factors that were positively associated with cognitive function in older adults were population density, street connectivity, walkability, number of public transportation stops around the residence, land use mix, neighborhood resources, green space, and quality of the neighborhood built environment. Built environment factors that were negatively associated with cognitive function in older adults were street integration, distance from residence to main road. The relationship between residential density, destination accessibility, and blue space with cognitive function in older adults needs to be further explored.

CONCLUSION

Preliminary evidence suggests an association between the neighborhood built environment and cognitive function in older adults. The causal relationship between the built environment and cognitive function can be further explored in the future using standardized and combined subjective and objective assessment methods, and longitudinal or quasi-experimental study designs. For public health interventions on the cognitive health of older adults, it is recommended that relevant authorities include the neighborhood built environment in their intervention programs.

Social Infrastructure Availability and Suicide Rates among Working-Age Adults in the United States

Social infrastructure (SI) may buffer against suicide risk by improving social cohesion, social support, and information and resource sharing. This study uses an ecological approach to examine the relationship between county-level SI availability and suicide rates among working-age adults (ages 25-64) in the United States, a population for whom suicide rates are high, rising, and geographically unequal. Mortality data are from the National Vital Statistics System for 2016-2019. SI data are from the National Neighborhood Data Archive for 2013-2015 and capture the availability of typically free SI (e.g. libraries, community centers) and commercial SI (e.g. coffee shops, diners, entertainment venues). Results from negative binomial models show that suicide rates are significantly lower in counties with more SI availability, net of county demographic, socioeconomic, and health care factors. This relationship held for both typically free and commercial SI. Policymakers should consider strengthening existing and developing new social infrastructure, particularly in counties with less educated populations, as part of a broader strategy to reduce suicide rates in the United States.

Neighborhood Built Environments and Health in Later Life: A Literature Review

Objectives: This literature review aims to assess the current state of the field linking neighborhood environments to later-life health and wellbeing. Methods: We used electronic databases (e.g., PubMed, Google Scholar, and ProQuest) to search for studies published between 2010 and 2022 examining associations between neighborhood built environmental variables and later-life physical, cognitive, mental, and social health outcomes. Results: Among 168 studies reviewed, the majority were quantitative (n = 144) and cross-sectional (n = 122). Neighborhood environmental variables significantly associated with later-life health outcomes included population density/rurality, walkability/street connectivity, access to services and amenities, neighborhood quality and disorder, and parks/green/blue/open space. Neighborhoods operated through behavioral and biological pathways including hazardous exposures, affective states (e.g., stress and restoration), and lifestyle (e.g., exercise, socialization, and diet). Discussion: Neighborhoods and healthy aging research is a burgeoning interdisciplinary and international area of scholarship. Findings can inform upstream community interventions and strengthen clinical care.

Neighborhood Cohesion Across the Life Course and Effects on Cognitive Aging

OBJECTIVES

Greater neighborhood cohesion is associated with better cognitive function in adulthood and may serve as a protective factor against cognitive impairment and decline. We build on prior work by examining the effects of perceived neighborhood cohesion across the life course on level and change in cognitive function in adulthood.

METHODS

Utilizing longitudinal data from the Health and Retirement Study (1998-2016) and its Life History Mail Survey, we leveraged data from 3,599 study participants (baseline age: 51-89) who participated in up to 10 waves. Respondents provided retrospective ratings of neighborhood cohesion at childhood (age 10), young adulthood (age at the first full-time job), early midlife (age 40), and concurrently at baseline (i.e., late midlife/adulthood); they completed the modified version of the Telephone Interview for Cognitive Status. We fit a univariate latent growth curve model of change in cognitive function across waves and tested whether neighborhood cohesion during each recollected life stage predicted level and change in cognitive function.

RESULTS

Greater neighborhood cohesion during childhood and late midlife/adulthood each predicted higher cognitive function at baseline but not the rate of cognitive decline. The final model showed that greater neighborhood cohesion in childhood and in late midlife/adulthood remained significantly associated with higher baseline cognitive function, even after accounting for one another.

DISCUSSION

Findings provide insight into life-course neighborhood contextual influences on cognitive aging. Our results emphasize the need for more research to understand the life-course dynamics between neighborhood environments and cognitive aging.

Characteristics of urban neighbourhood environments and cognitive age in mid-age and older adults

In this cross-sectional study, we examined the extent to which features of the neighbourhood natural, built, and socio-economic environments were related to cognitive age in adults (N = 3418, Mage = 61 years) in Australia. Machine learning estimated an individual's cognitive age from assessments of processing speed, verbal memory, premorbid intelligence. A 'cognitive age gap' was calculated by subtracting chronological age from predicted cognitive age and was used as a marker of cognitive age. Greater parkland availability and higher neighbourhood socio-economic status were associated with a lower cognitive age gap score in confounder- and mediator-adjusted regression models. Cross-sectional design is a limitation. Living in affluent neighbourhoods with access to parks maybe beneficial for cognitive health, although selection mechanisms may contribute to the findings.

Association of Perceived Neighborhood Environments With Cognitive Function in Older Adults

The current study examined the associations between perceptions of the social and physical neighborhood environments and cognitive function in older adults. This cross-sectional study analyzed 821 adults aged ≥65 years from the Adult Changes in Thought study. Perceived neighborhood attributes were measured by the Physical Activity Neighborhood Environment Scale. Cognitive function was assessed using the Cognitive Ability Screening Instrument. The associations were tested using multivariate linear regression. One point greater perceived access to public transit was associated with 0.56 points greater cognitive function score (95% confidence interval [CI] [0.25, 0.88]), and an additional one point of perceived sidewalk coverage was related to 0.22 points higher cognitive function score (95% CI [0.00, 0.45]) after controlling for sociodemographic factors. The perception of neighborhood attributes alongside physical infrastructure may play an important role in supporting older adults' cognitive function. [Journal of Gerontological Nursing, 49(8), 35-41.].

An Examination of the Joint Effect of the Social Environment and Air Pollution on Dementia Among US Older Adults

Evidence suggests exposure to air pollution increases the risk of dementia. Cognitively stimulating activities and social interactions, made available through the social environment, may slow cognitive decline. We examined whether the social environment buffers the adverse effect of air pollution on dementia in a cohort of older adults.

Methods

This study draws from the Ginkgo Evaluation of Memory Study. Participants aged 75 years and older were enrolled between 2000 and 2002 and evaluated for dementia semi-annually through 2008. Long-term exposure to particulate matter and nitrogen dioxide was assigned from spatial and spatiotemporal models. Census tract-level measures of the social environment and individual measures of social activity were used as measures of the social environment. We generated Cox proportional hazard models with census tract as a random effect and adjusted for demographic and study visit characteristics. Relative excess risk due to interaction was estimated as a qualitative measure of additive interaction.

Results

This study included 2,564 individuals. We observed associations between increased risk of dementia and fine particulate matter (µg/m3), coarse particulate matter (µg/m3), and nitrogen dioxide (ppb); HRs per 5 unit increase were 1.55 (1.01, 2.18), 1.31 (1.07, 1.60), and 1.18 (1.02, 1.37), respectively. We found no evidence of additive interaction between air pollution and the neighborhood social environment.

Conclusions

We found no consistent evidence to suggest a synergistic effect between exposure to air pollution and measures of the social environment. Given the many qualities of the social environment that may reduce dementia pathology, further examination is encouraged.

Availability of healthy foods, fruit and vegetable consumption, and cognition among urban older adults

BACKGROUND

. Although prior studies have examined the associations between neighborhood characteristics and cognitive health, little is known about whether local food environments, which are critical for individuals' daily living, are associated with late-life cognition. Further, little is known about how local environments may shape individuals' health-related behaviors and impact cognitive health. The aim of this study is to examine whether objective and subjective measures of healthy food availability are associated with ambulatory cognitive performance and whether behavioral and cardiovascular factors mediate these associations among urban older adults.

METHODS

. The sample consisted of systematically recruited, community-dwelling older adults (N = 315, mean age = 77.5, range = 70-91) from the Einstein Aging Study. Objective availability of healthy foods was defined as density of healthy food stores. Subjective availability of healthy foods and fruit/vegetable consumption were assessed using self-reported questionnaires. Cognitive performance was assessed using smartphone-administered cognitive tasks that measured processing speed, short-term memory binding, and spatial working memory performance 6 times a day for 14 days.

RESULTS

. Results from multilevel models showed that subjective availability of healthy foods, but not objective food environments, was associated with better processing speed (estimate= -0.176, p = .003) and more accurate memory binding performance (estimate = 0.042, p = .012). Further, 14~16% of the effects of subjective availability of healthy foods on cognition were mediated through fruit and vegetable consumption.

CONCLUSIONS

. Local food environments seem to be important for individuals' dietary behavior and cognitive health. Specifically, subjective measures of food environments may better reflect individuals' experiences regarding their local food environments not captured by objective measures. Future policy and intervention strategies will need to include both objective and subjective food environment measures in identifying impactful target for intervention and evaluating effectiveness of policy changes.