Social networks and cognitive function in older adults: findings from the HAPIEE study

Dementia: Common Syndromes and Modifiable Risk and Protective Factors

Dementia is an umbrella term for multiple conditions that lead to progressive cognitive decline and impaired activities of daily living. Neuropsychological evaluation is essential for characterizing the distinct cognitive and behavioral profile that can aid in the diagnostic process and treatment planning for dementia. Modifiable risk factors for dementia such as nutrition, physical activity, sleep, cognitive and social engagement, and stress provide important avenues for prevention. Neurologists and other health care providers can help patients reduce their risk for dementia by providing them with education about modifiable factors and connecting them to resources to empower them to engage in brain-healthy behavior.

The Effects of Video Presence on Associative and Source Memory Among Younger and Older Adults in a Virtual Social Simulation

The current study aimed to examine how video presence in a simulated virtual socialization meeting would affect younger (n = 60) and older adults' (n = 65) associative and source memory. Participants were instructed to watch a simulated virtual meeting where speakers introduced themselves with a name and an occupation, half with their video on and the other half with their video off. Participants completed a recognition test of intact, rearranged, and new name-occupation pairs. For pairs recognized as old, participants were asked to identify whether the pair was presented with their video on or off. The associative memory accuracy (i.e., hit rate - false alarm rate) results showed a better performance in younger relative to older adults, but both age groups benefited equally from video presence. Source memory (i.e., video-on vs. video-off) results showed a significant benefit of video presence in older but not younger adults.

Trajectories of cognitive function development and predictive factors in disabled middle-aged and older adults

Objective

To explore the trajectories of cognitive function development and predictive factors in disabled middle-aged and older adults.

Methods

Utilizing data from 983 disabled middle-aged and older adults in the China Health and Retirement Longitudinal Study (CHARLS) from 2013 to 2020, latent growth mixture models were constructed to analyze the categories of cognitive function development trajectories and their predictive factors.

Results

The cognitive function trajectories of the disabled middle-aged and older adults were classified into three categories: rapid decline (32.6%), Slow decline (36.1%), and Stable (31.2%). Multinomial logistic regression analysis identified age, gender, residence, education, marital status, household income, sleep duration, depression, hearing ability, and social participation as predictors of these trajectories.

Conclusion

There is heterogeneity in the cognitive function development trajectories among disabled middle-aged and older adults. Healthcare professionals can implement targeted health management based on the characteristics of different groups to prevent the deterioration of cognitive function in this population.

The relationship between social frailty and cognitive impairment among older adults: the role of various types of internet use

Introduction

This study aimed to explore the role of internet use in the relationship between social frailty and cognitive function among Korean older adults.

Methods

A nationally representative survey of community-dwelling older adults in Korea was used in the analysis (N = 8,639).

Results

All types of internet use were significantly associated with cognitive impairment and played a significant role in the relationship between social frailty and cognitive impairment. The advantage of internet use for information searching (OR 0.40, 95% CI 0.35-0.46) was the greatest for cognitive function, followed by internet use for instrumental use (OR 0.59, 95% CI 0.53-0.66). Internet use for entertainment exhibited the greatest influence in the relationship between social frailty and cognitive impairment, with interpersonal communication ranking second in significance. Internet use regulates the relationship between social frailty and cognitive impairment in older adults. The influences of internet use vary depending on the type of online activity and the levels of social frailty.

Discussion

This highlights the importance of considering various forms of internet use when developing non-pharmacological interventions to mitigate the impact of social frailty on cognitive decline.

Relationship between domain-specific physical activity and cognitive function in older adults - findings from NHANES 2011-2014

Objective

To determine the relationship between domain-specific physical activity (PA) (e.g., occupational PA [OPA], transport-related PA [TPA], and recreational PA [RPA]) and cognitive function in older adults.

Methods

The data was obtained from the 2011-2014 cycle of the NHANES. We utilized weighted multivariate linear regression models among the included 2,924 people aged 60 years or older for our purposes.

Results

RPA and total PA according to WHO guidelines were associated with verbal fluency (RPA β: 1.400, 95% CI: 0.776, 2.024, p = 0.002; total PA β: 1.115, 95% CI: 0.571, 1.659, p = 0.001), processing speed and executive function (RPA β: 2.912, 95% CI. 1.291, 4.534, p = 0.005; total PA β: 2.974, 95% CI: 1.683, 4.265, p < 0.001) were positively correlated, and total PA was correlated with delayed memory performance (β: 0.254, 95% CI: 0.058, 0.449, p = 0.019). No significant association was observed between OPA, TPA, and various aspects of cognitive function among individuals over 60 years.

Conclusion

There was no noteworthy correlation discovered between OPA and TPA in relation to cognitive function. However, RPA and total PA exhibited significant associations with verbal fluency, processing speed, and executive function. Additionally, maintaining PA levels ranging from 600 to 1,200 MET-min/week would yield the most favorable outcomes for cognitive function.

The Relationship Between Social Isolation and Cognitive Frailty Among Community-Dwelling Older Adults: The Mediating Role of Depressive Symptoms

Purpose

Social isolation and depression have an impact on cognitive frailty. However, the underlying mechanisms between these variables have not been well defined. This study aims to investigate the mediating role of depressive symptoms in the association between social isolation and cognitive frailty among older adults in China.

Methods

From Mar 2023 to Aug 2023, a cross-sectional study was conducted with 496 community-dwelling older adults aged ≥60 years in Nanjing, Jiangsu Province, China. Demographic information was collected using the General Information Questionnaire. The Lubben Social Network Scale-6 (LSNS-6), Geriatric Depression Scale 15-item (GDS-15), Montreal Cognitive Assessment (MoCA), Clinical Dementia Rating (CDR), and FRAIL scale were used for the questionnaire survey. Multiple linear regression and binary logistic regression were utilized to explore the associations among social isolation, depressive symptoms, and cognitive frailty, and Bootstrap analysis was used to explore the mediating role of depressive symptoms in social isolation and cognitive frailty.

Results

Linear regression results revealed that social isolation was positively associated with depressive symptoms (β = 0.873, p < 0.001). Logistic regression analysis showed that social isolation (OR = 1.769, 95% CI = 1.018~3.075) and depressive symptoms (OR = 1.227, 95% CI = 1.108~1.357) were significantly associated with cognitive frailty. Mediation analysis demonstrated that depressive symptoms significantly mediated the relationship between social isolation and cognitive frailty, with an indirect effect of 0.027 (95% CI = 0.003~0.051), and the mediating effect accounted for 23.6% of the total effect.

Conclusion

Social isolation is associated with cognitive frailty in community-dwelling older adults, and depressive symptoms partially mediate the effect between social isolation and cognitive frailty. Active promotion of social integration among older individuals is recommended to enhance their mental health, reduce the incidence of cognitive frailty, and foster active aging.

A Systematic Review and Meta-Analysis of Social Cognition Among People Living with HIV: Implications for Non-Social Cognition and Social Everyday Functioning

Social cognition-the complex mental ability to perceive social stimuli and negotiate the social environment-has emerged as an important cognitive ability needed for social functioning, everyday functioning, and quality of life. Deficits in social cognition have been well documented in those with severe mental illness including schizophrenia and depression, those along the autism spectrum, and those with other brain disorders where such deficits profoundly impact everyday life. Moreover, subtle deficits in social cognition have been observed in other clinical populations, especially those that may have compromised non-social cognition (i.e., fluid intelligence such as memory). Among people living with HIV (PLHIV), 44% experience cognitive impairment; likewise, social cognitive deficits in theory of mind, prosody, empathy, and emotional face recognition/perception are gradually being recognized. This systematic review and meta-analysis aim to summarize the current knowledge of social cognitive ability among PLHIV, identified by 14 studies focused on social cognition among PLHIV, and provides an objective consensus of the findings. In general, the literature suggests that PLHIV may be at-risk of developing subtle social cognitive deficits that may impact their everyday social functioning and quality of life. The causes of such social cognitive deficits remain unclear, but perhaps develop due to (1) HIV-related sequelae that are damaging the same neurological systems in which social cognition and non-social cognition are processed; (2) stress related to coping with HIV disease itself that overwhelms one's social cognitive resources; or (3) may have been present pre-morbidly, possibly contributing to an HIV infection. From this, a theoretical framework is proposed highlighting the relationships between social cognition, non-social cognition, and social everyday functioning.

How Loneliness Gets Under the Skin: Inflammation Mediates the Relationship Between Loneliness and Gait Speed

OBJECTIVE

Loneliness is linked to interleukin 6 (IL-6), a marker of systemic inflammation, which chronically has deleterious effects on physical and mental health across the adult life span. This study investigated cross-sectional relationships among loneliness, IL-6, demographics, multimorbidity, depression, obesity, friendship quantity, and slowed gait.

METHODS

Data from the Midlife Development in the United States Biomarker Project, a national adult sample ( N = 822; age range, 26-78 years) was used for this study. The PROCESS macro tested the hypothesis that IL-6 would mediate the relationship between loneliness and gait, after adjusting for demographic and health risk factors.

RESULTS

Age ( β = 0.292, p < .001), sex ( β = 0.197, p < .001), body mass index (BMI, β = 0.374, p < .001), waist-hip ratio ( β = 0.242, p < .001), and loneliness ( β = 0.089, p = .025) but not multimorbidity ( β = 0.043, p = .20), depression history ( β = 0.022, p = .47), depression symptoms ( β = 0.036, p = .28), and number of friends ( β = 0.022, p = .46) contributed to the variance in IL-6. Serial mediation analyses supported the chained effect of loneliness on walking time through BMI and IL-6. Results also showed specific indirect effects of BMI and IL-6 on walking time, suggesting more than one pathway by which loneliness influences health.

CONCLUSIONS

These results suggest that loneliness may increase the risk of systemic inflammation, leading to slowed gait and adverse health outcomes. Psychosocial interventions that address loneliness may provide an optimal treatment target for reducing inflammation and preventing declines in health.

Executive function mediates age-related variation in social integration in female vervet monkeys (Chlorocebus sabaeus)

In humans, social participation and integration wane with advanced age, a pattern hypothesized to stem from cognitive or physical decrements. Similar age-related decreases in social participation have been observed in several nonhuman primate species. Here, we investigated cross-sectional age-related associations between social interactions, activity patterns, and cognitive function in 25 group-living female vervets (a.k.a. African green monkeys, Chlorocebus sabaeus) aged 8-29 years. Time spent in affiliative behavior decreased with age, and time spent alone correspondingly increased. Furthermore, time spent grooming others decreased with age, but the amount of grooming received did not. The number of social partners to whom individuals directed grooming also decreased with age. Grooming patterns mirrored physical activity levels, which also decreased with age. The relationship between age and grooming time was mediated, in part, by cognitive performance. Specifically, executive function significantly mediated age's effect on time spent in grooming interactions. In contrast, we did not find evidence that physical performance mediated age-related variation in social participation. Taken together, our results suggest that aging female vervets were not socially excluded but decreasingly engaged in social behavior, and that cognitive deficits may underlie this relationship.

The influence of social participation and depressive symptoms on cognition among middle-aged and older adults

Background

The global aging phenomenon has raised concerns about the cognitive abilities of older individuals. This study aimed to explore the relationship between social participation, depressive symptoms, and cognitive function among middle-aged and older adults.

Methods

This study utilized data from the China Longitudinal Study of Health and Retirement (CHARLS) from wave 1 to wave 4. We used linear regression and generalized estimation equations to investigate the correlation between social participation, depressive symptoms, and cognitive function. Moreover, three models were constructed by adjusting covariates, and we used the sobel test and bootstrap method to analyze the mediating effects of depressive symptoms on social activities and cognitive function.

Results

The results of both linear regression and generalized estimation equation showed that social participation had a positive correlation with cognitive function (P < 0.05), and the impact of social participation on cognition increased with the number of social activity types. Meanwhile, depressive symptoms had a negative association with cognitive function (P < 0.05). Furthermore, there was no interaction between social participation and depressive symptoms on cognitive function. Finally, after adjusting the model, social participation could affect cognitive function by affecting depressive symptoms (P < 0.05).

Conclusion

The study emphasizes the mediating role of depressive symptoms in the relationship between social participation and cognitive function. Notably, no interaction was observed between social participation and depressive symptoms. These findings highlight the potential of active social participation in reducing depressive symptoms and enhancing cognitive function in middle-aged and older adults.

Association of social integration with cognitive function trajectories among Chinese older adults: evidence from the China health and retirement longitudinal study (CHARLS)

Background

The prevalence of cognitive impairment among older adults remains high. It has been proven that social integration is related to cognitive function. However, limited research has examined the association of social integration and its different dimensions with cognitive function trajectories of older adults.

Methods

The data were from the China Health and Retirement Longitudinal Study (CHARLS) spanning 2013 (T1) to 2018 (T3). A total of 3,977 older adults were included in the final analysis. Cognitive function was measured with items from an adapted Chinese version of the Mini-Mini-Mental Mental State Examination (MMSE), while the measurement of social integration included three dimensions: economic integration, relational integration and community integration. A group-based trajectory model (GBTM) was used to identify cognitive trajectory groups among participants and an unordered multinomial logistic regression was employed to explore the association of baseline social integration and its three dimensions with cognitive function trajectories.

Result

Three cognitive function trajectory groups were identified: low-decline group (24.1%), medium-decline group (44.2%) and high-stable group (31.7%). Comparing to the medium-decline trajectory group, older adults with higher social integration scores were more likely to be in the high-stable trajectory group (OR = 1.087, 95%CI: 1.007 ~ 1.174), while less likely to be in the low-decline group (OR = 0.806, 95%CI: 0.736 ~ 0.882). Among the different dimensions of social integration, older adults with higher community integration scores were more likely to be in the high-stable trajectory group (OR = 1.222, 95%CI: 1.026 ~ 1.456); Older adults with higher relational integration scores were less likely to be in the low-decline trajectory group (OR = 0.816, 95%CI: 0.734 ~ 0.906). The economic integration was not found to correlate with the cognitive function trajectories. Stratified analyses revealed that the association between community integration and cognitive trajectories was only significant among older adults aged 60 to 69, and the association between relational integration and cognitive trajectories was only significant among older adults who was agricultural household registration.

Conclusion

The developmental trajectories of cognitive function among Chinese older adults are heterogeneous. Social integration is significantly related to the trajectories of cognitive function in Chinese older adults. Measures should be taken to promote social integration of Chinese older adults to reduce the decline of cognitive function.

Correlation between air pollution and cognitive impairment among older individuals: empirical evidence from China

BACKGROUND

Little information is available regarding the impact of air pollution on cognitive impairment in older individuals in developing countries. This study empirically tested the impacts of the air quality index (AQI), air pollution intensity (quantified by the number of days of extreme air pollution in a year), and different pollutants on the cognitive abilities of older Chinese individuals.

METHODS

A panel of 28,395 participants spanning 122 cities in 2015 and 2018 was used, based on 3-year follow-up survey data from the China Health and Retirement Longitudinal Study (CHARLS) database. Data from the two phases of the CHARLS microsurvey were combined with relevant statistical data on air pollution in each region in the current year. These two surveys were used to investigate changes in basic health and macro-environmental indicators in older individuals in China, and a mean difference test was conducted. We then reduced the sample selection error by controlling for environmental migration and used two-way fixed and instrumental variable methods for endogenous treatment to avoid the estimation error caused by missing variables.

RESULTS

Air pollution had a significantly negative effect on the cognitive abilities of older individuals (odds ratio [OR]: 1.4633; 95% confidence interval [95% CI]: 1.20899-1.77116). Different pollution intensities(only AQI value is greater than 200 or more) had apparent effects on cognitive impairment, with an OR of approximately 1.0. Sulfur dioxide had significantly negative effects on cognitive ability, with OR of 1.3802 (95% CI: 1.25779-1.51451). Furthermore, air pollution impact analysis showed heterogeneous results in terms of age, sex, education, and regional economic development level. In addition, social adaptability (calculated using social participation, learning, adaptability, and social support) not only had a significant positive effect on the cognitive abilities of older individuals, but also regulated the cognitive decline caused by air pollution.

CONCLUSIONS

Air pollution affects cognitive impairment in older individuals, especially in those with lower education levels, and living in economically underdeveloped areas. This effect is synchronous and has a peak at an AQI of > 200.

Examining the social networks of older adults receiving informal or formal care: a systematic review

PURPOSE

To address the care needs of older adults, it is important to identify and understand the forms of care support older adults received. This systematic review aims to examine the social networks of older adults receiving informal or formal care and the factors that influenced their networks.

METHODS

A systematic review was conducted by searching six databases from inception to January 31, 2023. The review included primary studies focusing on older adults receiving long-term care, encompassing both informal and formal care. To assess the risk of bias in the included studies, validated appraisal tools specifically designed for different study types were utilized. Network analysis was employed to identify the grouping of study concepts, which subsequently formed the foundation for describing themes through narrative synthesis.

RESULTS

We identified 121 studies relating to the formal and informal care of older adults' networks. A variety of social ties were examined by included studies. The most commonly examined sources of care support were family members (such as children and spouses) and friends. Several factors were consistently reported to influence the provision of informal care, including the intensity of networks, reciprocity, and geographical proximity. In terms of formal care utilization, older age and poor health status were found to be associated with increased use of healthcare services. Additionally, physical limitations and cognitive impairment were identified as factors contributing to decreased social engagement.

CONCLUSION

This review found that older people were embedded within a diverse network. The findings of this review emphasize the importance of recognizing and incorporating the diversity of social networks in care plans and policies to enhance the effectiveness of interventions and improve the overall well-being of older adults.

Investigating Heterogeneity in the Relationship Between Marital Satisfaction and Cognitive Health by Gender and Across the Cognitive Function Distribution

Background and Objectives

Marital satisfaction has been established as an essential factor for promoting health and well-being in older adults. However, it is unclear whether marital satisfaction is also associated with cognitive health in this population. This study aimed to investigate the longitudinal association between marital satisfaction and cognitive function, while also exploring variations in this relationship by gender and across the cognitive function distribution.

Research Design and Methods

This study used 6 waves of the Korean Longitudinal Study of Ageing (KLoSA) and employed gender-stratified unconditional quantile regression (UQR) models with fixed effects (FE) to estimate the association between marital satisfaction and cognitive function across different quantiles of the cognitive function distribution. FE models controlled for unobserved individual-level confounders such as genetics, cognitive and noncognitive skills, and early childhood social and cultural background.

Results

The results of this study revealed that marital satisfaction was positively associated with cognitive function (b = 0.305), and this association was stronger in older men than in older women (b = 0.392 for older men vs b = 0.181 for older women). The UQR-FE models suggested that stronger association between marital satisfaction and cognitive function was observed among older men with lower cognitive function (b = 0.817 for 10th percentile vs b = 0.118 for 90th percentile). Among older women, no clear patterns of heterogeneity were found across the cognitive function distribution.

Discussion and Implications

The findings of this study highlight a significant degree of heterogeneity in the relationship between marital satisfaction and cognitive function among older men, with stronger associations observed in the lower percentiles of the cognitive function distribution. Interventions aimed at improving marital quality could be an effective strategy for promoting cognitive health in older adults, with an approach tailored to the individual's characteristics.

Lifestyle Enrichment in Later Life and Its Association With Dementia Risk

Importance

Lifestyles enriched with socially and mentally stimulating activities in older age may help build cognitive reserve and reduce dementia risk.

Objective

To investigate the association of leisure activities and social networks with dementia risk among older individuals.

Design, Setting, and Participants

This longitudinal prospective cohort study used population-based data from the ASPREE Longitudinal Study of Older Persons (ALSOP) for March 1, 2010, to November 30, 2020. Community-dwelling individuals in Australia aged 70 years or older who were generally healthy and without major cognitive impairment at enrollment were recruited to the ALSOP study between March 1, 2010, and December 31, 2014. Data were analyzed from December 1, 2022, to March 31, 2023.

Exposures

A total of 19 measures of leisure activities and social networks assessed at baseline were classified using exploratory factor analysis.

Main Outcomes and Measures

Dementia was adjudicated by an international expert panel according to Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) criteria. Cox proportional hazards regression examined dementia risk over 10 years, adjusting for education, socioeconomic status, and a range of health-related factors.

Results

This study included 10 318 participants. Their median age was 73.8 (IQR, 71.6-77.2) years at baseline, more than half (52.6%) were women, and most self-identified as White (98.0%). In adusted analyses, more frequent engagement in adult literacy activities (eg, writing letters or journaling, using a computer, and taking education classes) and in active mental activities (eg, playing games, cards, or chess and doing crosswords or puzzles) was associated with an 11.0% (adjusted hazard ratio [AHR], 0.89 [95% CI, 0.85-0.93]) and a 9.0% (AHR, 0.91 [95% CI, 0.87-0.95]) lower risk of dementia, respectively. To a lesser extent, engagement in creative artistic activities (craftwork, woodwork, or metalwork and painting or drawing) (AHR, 0.93 [95% CI, 0.88-0.99]) and in passive mental activities (reading books, newspapers, or magazines; watching television; and listening to music or the radio) (AHR, 0.93 [95% CI, 0.86-0.99]) was also associated with reduced dementia risk. In contrast, interpersonal networks, social activities, and external outings were not associated with dementia risk in this sample.

Conclusions and Relevance

These results suggest that engagement in adult literacy, creative art, and active and passive mental activities may help reduce dementia risk in late life. In addition, these findings may guide policies for geriatric care and interventions targeting dementia prevention for older adults.

Social support and cognitive function in Chinese older adults who experienced depressive symptoms: is there an age difference?

Objective

This study examined the moderating effect of overall social support and the different types of social support on cognitive functioning in depressed older adults. We also investigated whether the moderating effect varied according to age.

Methods

A total of 2,500 older adults (≥60 years old) from Shanghai, China were enrolled using a multistage cluster sampling method. Weighted linear regression and multiple linear regression was utilized to analyze the moderating effect of social support on the relationship between depressive symptoms and cognitive function and to explore its differences in those aged 60-69, 70-79, and 80 years and above.

Results

After adjusting for covariates, the results indicated that overall social support (β = 0.091, p = 0.043) and support utilization (β = 0.213, p < 0.001) moderated the relationship between depressive symptoms and cognitive function. Support utilization reduced the possibility of the cognitive decline in depressed older adults aged 60-69 years (β = 0.310, p  < 0.001) and 80 years and above (β = 0.199, p  < 0.001), while objective support increased the possibility of cognitive decline in depressed older people aged 70-79 years (β = -0.189, p  < 0.001).

Conclusion

Our findings highlight the buffering effects of support utilization on cognitive decline in depressed older adults. We suggest that age-specific measures should be taken when providing social support to depressed older adults in order to reduce the deterioration of cognitive function.

The Molecular Effects of Environmental Enrichment on Alzheimer's Disease

Environmental enrichment (EE) is an environmental paradigm encompassing sensory, cognitive, and physical stimulation at a heightened level. Previous studies have reported the beneficial effects of EE in the brain, particularly in the hippocampus. EE improves cognitive function as well as ameliorates depressive and anxiety-like behaviors, making it a potentially effective neuroprotective strategy against neurodegenerative diseases such as Alzheimer's disease (AD). Here, we summarize the current evidence for EE as a neuroprotective strategy as well as the potential molecular pathways that can explain the effects of EE from a biochemical perspective using animal models. The effectiveness of EE in enhancing brain activity against neurodegeneration is explored with a view to differences present in early and late life EE exposure, with its potential application in human being discussed. We discuss EE as one of the non pharmacological approaches in preventing or delaying the onset of AD for future research.

The Association between Physical Activity and Cognitive Function: Data from the China Health and Nutrition Survey

Background

Decreased cognitive function is a common problem in the old adults, which has high risk of progression to Alzheimer's diseases (AD) and other dementias. This study was aimed at finding out the association between physical activity and cognitive function.

Methods

In total, 1514 participants with the age ≥ 55 years old registered in the China Health and Nutrition Survey (CHNS) database were selected in this study. The association between physical activity and cognitive function was analyzed via the generalized additive model. The association between the variables and the cognitive function score was expressed as β coefficient with 95% confidence intervals (CIs).

Results

After adjusting age, ethnicity, stratum, marital status, education, memory status, and memory changes, the cognitive function score was increased by 0.011 points for every 1-point increase in domestic score (β = 0.011, P = 0.043). Subgroup analysis indicated that in the female group, for every 1-point increase in the domestic score, the cognitive function score increased by 0.019 points (β = 0.019, P = 0.017). In people with good memory status, each 1-point increase in domestic score increased the cognitive function score of 0.020 points (β = 0.020, P = 0.017).

Conclusions

The decreased cognitive function was correlated with decreased domestic physical activity. The increased domestic physical activity was associated with an increased cognitive function in females and people with good memory status. The findings might offer a reference for deep understanding of the association between physical activity and cognitive function.

Association Between Social Network and Cognitive Function: A Cross-Sectional Assessment From the Cardiovascular and Metabolic Diseases Etiology Research Center Cohort (2013-2018)

BACKGROUND

This study aimed to investigate how social networks are associated with cognitive function in the middle-aged and elderly Korean population.

METHODS

A total of 7,704 individuals over the age of 50 were included from the baseline recruitment of the Cardiovascular and Metabolic Diseases Etiology Research Center cohort from the years 2013 to 2018. Egocentric social network characteristics including network size, intimacy, and frequency of face-to-face meetings were measured as exposures, and the Korean version of Mini-Mental State Examination (K-MMSE) score was measured to reflect general cognitive function as an outcome. We also stratified the analysis by income level into tertiles, with income caps of 42,000 thousand won and 72,000 thousand won. A general linear regression model was used, adjusting for age, gender, socioeconomic factors, lifestyle factors, depressive symptoms, and study settings.

RESULTS

Social network properties were positively associated with cognitive function in both men and women. However, the specific estimates varied according to gender and income level. In men, frequency was most significantly associated with cognitive function (standardized β = 0.093, p-value <0 .0001). In women, the strength of the association with cognitive function was found in size (standardized β = 0.055, p-value = 0.001). The effect modification of income level could be seen in the association between frequency and cognitive function. The strongest association between frequency and cognitive function was found in the middle income group in men (standardized β = 0.114, p-value = 0.0063), and the low income group in women (standardized β = 0.076, p-value = 0.0039).

CONCLUSION

There were positive associations between social network properties (i.e., size, intimacy, and frequency of face-to-face meetings) and cognitive function. The degree of association varied according to social network properties, gender, and income level. Overall, among social network properties, social network size was an important factor in the cognition of women, whereas frequency was important in the cognition of men.

Association of Physical Activity With Cognitive Function Among Older Adults in Rural Sichuan, China

The purpose of this study was to explore the relationship between total physical activity and different dimensions of cognitive function (orientation, attention, and memory) among older adults in rural Sichuan, China. This cross-sectional study involved 715 older adults (average age of 72 years). Total PA was measured by the Physical Activity Scale for the Elderly, and cognitive function was assessed by the Telephone Interview for Cognitive Status (TICS) questionnaire. The multivariate linear regression analysis indicated that total PA and household PA were significantly associated with the overall Telephone Interview for Cognitive Status score (β = 0.143, p < .001; β = 0.115, p = .002, respectively), the orientation dimension (β = 0.142, p < .001; β = 0.131, p = .001, respectively), and the memory dimension (β = 0.179, p < .001; β = 0.134, p = .001, respectively). The study showed a positive association between total PA, household PA, and cognitive function in older adults, especially in the orientation dimension and the memory dimension of cognitive function.