Loneliness mediates the relationships between perceived neighborhood characteristics and cognition in middle-aged and older adults

Does Neighborhood Socioeconomic Status Alter Memory Change Associated with a Cancer Diagnosis? Preliminary Evidence from the US Health and Retirement Study

BACKGROUND

Neighborhood disadvantage has been linked to cognitive impairment, but little is known about the effect of neighborhood disadvantage on long-term cancer-related memory decline.

METHODS

Incident cancer diagnosis and memory (immediate and delayed recall, combined with proxy-reported memory) were assessed at biennial interviews in the US Health and Retirement Study (N = 13,293, 1998-2016). Neighborhood disadvantage was measured using the National Neighborhood Data Archive disadvantage index, categorized into tertiles (T1: least disadvantaged-T3: most disadvantaged). Linear mixed-effects models estimated the standardized memory trajectories in participants with or without cancer, by neighborhood disadvantage.

RESULTS

Living in more disadvantaged neighborhoods was associated with worse mean memory function and steeper memory declines, regardless of cancer status. An incident cancer diagnosis was associated with an acute memory drop for those living in least disadvantaged neighborhoods but not more disadvantaged neighborhoods [T1: -0.05, 95% confidence interval (CI): -0.08, -0.01; T3: -0.13, 95% CI: -0.06, 0.03]. Cancer survivors in the least disadvantaged neighborhoods had a slight memory advantage in the years prior to diagnosis (T1: 0.09, 95% CI: 0.04, 0.13) and after diagnosis (T1: 0.07, 95% CI: 0.01, 0.13).

CONCLUSIONS

An incident cancer diagnosis among those living in the least disadvantaged neighborhoods was associated with an acute memory drop at the time of diagnosis and a long-term memory advantage before and after diagnosis compared with cancer-free individuals in similar neighborhoods.

IMPACT

These findings could inform interventions to promote cancer survivor's long-term aging. Future studies should investigate the social and biological pathways through which neighborhood socioeconomic status could influence cancer-related memory changes.

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.

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.

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.].

Association between loneliness and its components and cognitive function among older Chinese adults living in nursing homes: A mediation of depressive symptoms, anxiety symptoms, and sleep disturbances

OBJECTIVE

This study aimed to investigate the associations between loneliness and its components and cognitive function among older Chinese adults living in nursing homes and to test whether depressive symptoms, anxiety symptoms, and sleep disturbances mediate these associations.

METHODS

The sample comprised 228 Chinese individuals aged ≥ 65 years living in nursing homes who were free of dementia and psychiatric or serious somatic diseases. Loneliness was evaluated using the UCLA Loneliness Scale. Global cognitive function was assessed using the Beijing version of the Montreal Cognitive Assessment. Multivariable linear regression analyses were performed to examine the associations between loneliness and its components and global cognitive function. A mediation analysis was used to test the potential mediating effects of depressive symptoms, anxiety symptoms, and sleep disturbances.

RESULTS

The mean (SD) age of the participants was 80.8 (6.3) years, and 58.3% were women. Compared with the lowest quartile of loneliness degree, the multivariable-adjusted beta coefficient (95% confidence interval [95% CI]) for the highest quartile was -1.32 (-2.61 to -0.02) (P for trend = 0.03). Loneliness components, personal feelings of isolation and the lack of relational connectedness but not the lack of collective connectedness, were also inversely associated with cognitive function. Significant indirect effects on cognitive function were observed for loneliness and its two components (personal feelings of isolation and the lack of relational connectedness) in mediating pathways via depressive symptoms, anxiety symptoms, and sleep disturbances (all p < 0.05).

CONCLUSIONS

A higher degree of loneliness and its two components, personal feelings of isolation and the lack of relational connectedness, are associated with worse cognitive function among Chinese residents in nursing homes. Depressive symptoms, anxiety symptoms, and sleep disturbances may at least partially mediate these associations.