Social isolation, rather than loneliness, is associated with cognitive decline in older adults: the China Health and Retirement Longitudinal Study

Association of social gatherings and physical exercise with depressive symptoms among middle-aged and older adults during the COVID-19 pandemic

Strict social isolation and physical distancing measures implemented during the COVID-19 pandemic had significant implications for the psychological well-being of middle-aged and older adults. This study aimed to investigate factors associated with depressive symptoms during the pandemic period among individuals who reported no significant depressive symptoms before the pandemic. Individuals from the Korean Longitudinal Study of Aging without a previous report of significant depressive symptoms across Waves 6 (2016) and 7 (2018) were investigated for the development of depressive symptoms in Wave 8 (2020). The multivariable logistic regression results revealed that both men and women who participated in social gatherings and physical exercise less than once a week were associated with an increase in the likelihood of depressive symptoms (odds ratio [OR] 2.88; 95% confidence interval [CI] 1.80-4.61 and OR 2.61; 95% CI 1.64-4.15, respectively for men and OR 2.58; 95% CI 1.80-3.70 and OR 1.51; 95% CI 1.02-2.23, respectively for women). In addition, unmarried men (OR 2.38; 95% CI 1.37-4.14) and women with one chronic disease (OR 1.98; 95% CI 1.14-3.43) or two or more chronic diseases (OR 2.28; 95% CI 1.31-3.99) reported a significant increase in the likelihood of depressive symptoms. Regular social gatherings and physical exercise were identified as key factors in mitigating depressive symptoms among middle-aged and older adults. The findings can inform the development of public health strategies that promote regular social interactions and physical activity to enhance the psychological resilience and overall well-being of middle-aged and older adults in the endemic era.

Exploring the differential impacts of social isolation, loneliness, and their combination on the memory of an aging population: A 6-year longitudinal study of the CLSA

Memory plays a crucial role in cognitive health. Social isolation (SI) and loneliness (LON) are recognized risk factors for global cognition, although their combined effects on memory have been understudied in the literature. This study used three waves of data over six years from the Canadian Longitudinal Study on Aging to examine whether SI and LON are individually and jointly associated with memory in community-dwelling middle-aged and older adults (n = 14,208). LON was assessed with the question: "In the last week, how often did you feel lonely?". SI was measured using an index based on marital/cohabiting status, retirement status, social activity participation, and social network contacts. Memory was evaluated with combined z-scores from two administrations of the Rey Auditory Verbal Learning Test (immediate-recall, delayed-recall). We conducted our analyses using all available data across the three timepoints and retained participants with missing covariate data. Linear mixed models were used to regress combined memory scores onto SI and LON, adjusting for sociodemographic, health, functional ability, and lifestyle variables. Experiencing both SI and LON had the greatest inverse effect on memory (least-squares mean: -0.80 [95 % confidence-interval: -1.22, -0.39]), followed by LON alone (-0.73 [-1.13, -0.34]), then SI alone (-0.69 [-1.09, -0.29]), and lastly by being neither lonely nor isolated (-0.65 [-1.05, -0.25]). Sensitivity analyses confirmed this hierarchy of effects. Policies developed to enhance memory in middle-aged and older adults might achieve greater benefits when targeting the alleviation of both SI and LON rather than one or the other individually.

Associations between sensory impairment and functional limitations among older Chinese adults: mediating roles of social isolation and cognition

BACKGROUND

The high prevalence of sensory impairment and functional limitations in older adults is a significant concern, yet there is limited understanding of the relationship between these two conditions. Therefore, the objective of this study was to investigate the pathways connecting sensory impairment and functional limitations by examining serial multiple mediating effects of social isolation and cognition in older adults.

METHODS

Using the China Health and Retirement Longitudinal Study dataset, a sample of 4871 older adults was selected. The study variables included sensory impairment, functional limitations, social isolation and cognition, and other covariates. A hierarchical multiple linear regression model was used to assess the association between sensory impairment and functional limitations. Mediation analysis was conducted to explore the sequential multiple mediating effects of social isolation and cognitive function in the relationship between sensory impairment and functional limitations.

RESULTS

Our findings revealed a significant and positive association between sensory impairment and functional limitations (B = 0.615, 95% CI: 0.397, 0.834). After adjusting for social isolation and cognitive function, the impact of sensory impairment on functional limitations accounted for 87.19% of the total effect. Additionally, approximately 12.81% of the significant relationship between dual sensory impairment and functional limitations was mediated by social isolation and cognitive function. A serial multiple mediating pathway (sensory impairment → social isolation → cognition → functional limitations) was identified, with a coefficient of 0.013 (95% CI: 0.006, 0.020).

CONCLUSIONS

Our study provides evidence for the mediating effects of social isolation and cognition in the relationship between sensory impairment and functional limitations. Given the prevalence of functional limitations among older adults with sensory impairment, it is crucial to consider social isolation and cognitive function in efforts to reduce the burden of disability care. Future validation of these findings through longitudinal studies is necessary.

Development and validation of a risk prediction model for older adults with social isolation in China

BACKGROUND

Older adults are vulnerable to social isolation due to declining physical and cognitive function, decreased interpersonal interactions, and reduced outdoor activities after retirement. This study aimed to develop and validate a predictive model to assess the risk of social isolation among older adults in China.

METHODS

Using data from the 2011 China Health and Retirement Longitudinal Study (CHARLS). The study cohort was randomly divided into training and validation groups in a 70:30 ratio. We used least absolute shrinkage and selection operator (LASSO) regression analysis with tenfold cross-validation to identify optimal predictive factors and examined the correlates of social isolation using logistic regression. A nomogram was constructed for the predictive model, and its accuracy was assessed using calibration curves. The predictive performance of the model was assessed using area under the receiver operating characteristic (ROC) curve and decision curve analysis (DCA).

RESULTS

From the 2011 CHARLS database, 4,747 older adults were included in the final analysis, of whom 1,654 (34.8%) experienced social isolation. Multifactorial logistic regression identified educational level, marital status, gender, physical activity, physical self -maintenance ability, and number of children as predictive factors for social isolation. The predictive model achieved an AUC of 0.739 (95%CI = 0.722-0.756) in the training set and 0.708 (95%CI = 0.681-0.735) in the validation set. The Hosmer-Lemeshow test yielded P values of 0.111 and 0.324, respectively (both P > 0.05), indicating significant agreement between the nomogram and observed outcomes. The nomogram showed excellent predictive ability according to ROC and DCA.

CONCLUSIONS

The predictive model developed to assess the risk of social isolation in the Chinese older adults shows promising utility for early screening and intervention by clinical healthcare professionals.

Impact of social wellbeing on tooth loss and cognition: A scoping review

OBJECTIVE

The proposed explanations for the association between tooth loss and cognitive function have largely focused on systemic inflammation, mechanoreceptor feedback, and nutritive deficiencies. However, the role of social wellbeing in this relationship remains unknown. The aim of this scoping review is to explore the pathways linking different aspects of social function, collectively grouped under the umbrella of social wellbeing, to tooth loss and cognitive impairment.

DATA AND SOURCES

An electronic database search was performed in PubMed, Scopus, and Embase. Reference lists of relevant articles were also searched. Data on the associations between social wellbeing, cognitive function and tooth loss was charted in an extraction form and summarised qualitatively.

STUDY SELECTION

From the initial search of 3293 records, 71 studies were included in the present review. Forty-seven studies investigated the relationship between social wellbeing and cognition, 21 studies investigated the relationship between social wellbeing and tooth loss, and only 3 studies investigated all three variables.

CONCLUSION

This review demonstrates the need for further research on tooth loss, cognition and social wellbeing in tandem and describes potential psychological, biological, cognitive, and behavioural mechanisms interlinking these factors. While substantial evidence was found for the association between social relationships and cognition, fewer studies explored the potentially bidirectional relationship of social wellbeing and tooth loss.

CLINICAL SIGNIFICANCE

The implications of this review may guide clinicians to focus on the social consequences of tooth loss, which may have broader repercussions on cognitive health. The role of social support in helping older people cope with oral disease and the benefits of fostering positive lifestyle habits should not be underestimated.

The effect of social isolation on the cognitive ability of the oldest old in Chinese nursing homes in post-COVID-19: a moderated chain mediation model

Background

Both pre-or post-COVID-19, older adults residing in nursing homes are at significant risk for social isolation, which is negatively associated with cognitive ability. Currently, the elderly aged 80 years and older are the fastest-growing age group globally. The extent of social isolation within this group post-COVID-19 and its impact on cognitive abilities remain inadequately explored.

Objective

This research aimed to evaluate the prevalence of social isolation among the oldest old in Chinese nursing homes post-COVID-19 and to investigate the mediating and moderating roles of basic activities of daily living (BADL), depression, and subjective socioeconomic status in the relationship between social isolation and cognitive ability.

Methods

This cross-sectional study included 453 participants aged 80 years and older from 11 nursing homes in Ningbo, Zhejiang Province, China. Social isolation was assessed using the Lubben Social Network Scale-6 (LSNS-6), cognitive ability using the Mini-Mental State Examination (MMSE), BADL using the Barthel Index (BI), and depression using the Patient Health Questionnaire-9 items (PHQ-9). Mediation and moderation effects were statistically analyzed using SPSS 23.0 and PROCESS 3.5.

Results

The mean age of the study sample was 87.1 ± 3.8 years, among whom 60.3% (n = 273) were female, and 56.1% experienced social isolation, with 41.1% and 63.1% being isolated from family and friends, respectively. Social isolation indirectly affected cognitive ability through BADL and depression, respectively, and through the chain mediation effect of BADL and depression. Subjective socioeconomic status moderated the relationships between social isolation and BADL and between social isolation and depression. However, no moderating effect of subjective socioeconomic status was found between social isolation and cognitive ability.

Conclusion

This study deepens our understanding of the current state of social isolation and its mechanisms of action in the oldest old post-COVID-19 and provides a new basis for future public health policy development and related research.

A prospective association between social isolation and cognitive performance among older adults in Europe: the role of loneliness and poor oral health

OBJECTIVES

The relationship between social isolation, loneliness, and tooth loss and cognition in older people is poorly understood. We examine how social isolation and cognitive performance are associated prospectively among older adults, as well as how tooth loss and loneliness are related to this association.

METHODS

Using data from 26,168 participants aged ≥50 from the Survey of Health, Ageing and Retirement in Europe (SHARE), we explored the association between social isolation, loneliness, tooth loss and cognition. We used bootstrapping with resampling strategies for testing a moderated mediating model.

RESULTS

Higher social isolation was associated with poorer cognitive performance (B = -0.20, 95% CI = -0.03, -0.01; R2 =0.60), an association mediated by the respondent's number of missing teeth (B = -0.001, 95% CI = -0.002, -0.001). Higher levels of social isolation were associated with a greater number of missing teeth, and a higher number of missing teeth was linked with poorer cognition. We also found that loneliness moderated the relationship between social isolation and both the number of missing teeth (B = -0.11, p  = 0.047) and cognitive performance.

CONCLUSION

In later life, social isolation and loneliness are associated with shoddy oral health and poor cognitive status. Clinicians and policymakers should be aware of both the association between social isolation and feelings of loneliness on dentition and oral health and their relationship to the cognitive status of older adults.

Analysis of changes in social isolation, loneliness, or both, and subsequent cognitive function among older adults: Findings from a nationwide cohort study

INTRODUCTION

The study aimed to investigate the associations of changes in social isolation, loneliness, or both, with cognitive function.

METHODS

Data were from 7299 older adults in the Chinese Longitudinal Healthy Longevity Survey. We defined four change patterns (no, incident, transient, and persistent) for social isolation and loneliness, and created nine-category variable to represent the joint changes. Tobit regression models and Cox models were performed.

RESULTS

Incident, transient, and persistent social isolation or loneliness may accelerate cognitive decline (p < 0.05). Incident, transient, and persistent social isolation were associated with higher cognitive impairment risk, while only persistent loneliness was associated with higher cognitive impairment risk (p < 0.001). Notably, short-term or persistent social isolation was associated with accelerated cognitive decline and incident cognitive impairment, regardless of different loneliness change status (p < 0.05).

DISCUSSION

Short-term or persistent social isolation and persistent loneliness may be a salient risk factor for cognitive decline and cognitive impairment.

HIGHLIGHTS

Incident, transient, and persistent social isolation were associated with accelerated cognitive decline and higher cognitive impairment risk. Persistent loneliness was associated with accelerated cognitive decline and higher cognitive impairment risk. Short-term or persistent social isolation with concurrent different loneliness change status accelerated cognitive decline and higher cognitive impairment risk.

Functional social isolation mediates the association between depression and executive function in older women: findings from the Canadian Longitudinal Study on Aging Comprehensive cohort

Depression and social isolation increase risk for executive function declines and are among the top five modifiable risk factors for dementia. However, the interrelationships between depression, social isolation and executive function are not well established. Further evidence is needed to inform strategies to promote executive function and independence in older age. We examined whether social isolation mediated the association between depression and executive function in community-dwelling middle-aged and older adults and whether this association was modified by age and sex. Adults aged 45 to 85 years from the Canadian Longitudinal Study on Aging (CLSA) Comprehensive cohort were followed over three years (complete case analysis, n = 14,133). Baseline depressive symptoms, a history of clinical depression, and functional social isolation (perceived lack of social support) were self-reported. Executive function at follow-up was a composite measure of five cognitive tests. Conditional process analysis assessed the mediating effects of functional social isolation across age group and sex, adjusted for sociodemographic and health covariates. Functional social isolation significantly mediated the association of depressive symptoms (proportion mediated [PM] = 8.0%) or clinical depression (PM = 17.5%) with executive function only among women aged 75+ years. Functional social isolation explains a proportion of the total effect of depressive symptoms or clinical depression on executive function in women aged 75 and older. Although reverse causation cannot be ruled out, our findings suggest that interventions that reduce functional social isolation or depression in older women may promote executive function.

Objective monitoring of loneliness levels using smart devices: A multi-device approach for mental health applications

Loneliness is linked to wide ranging physical and mental health problems, including increased rates of mortality. Understanding how loneliness manifests is important for targeted public health treatment and intervention. With advances in mobile sending and wearable technologies, it is possible to collect data on human phenomena in a continuous and uninterrupted way. In doing so, such approaches can be used to monitor physiological and behavioral aspects relevant to an individual's loneliness. In this study, we proposed a method for continuous detection of loneliness using fully objective data from smart devices and passive mobile sensing. We also investigated whether physiological and behavioral features differed in their importance in predicting loneliness across individuals. Finally, we examined how informative data from each device is for loneliness detection tasks. We assessed subjective feelings of loneliness while monitoring behavioral and physiological patterns in 30 college students over a 2-month period. We used smartphones to monitor behavioral patterns (e.g., location changes, type of notifications, in-coming and out-going calls/text messages) and smart watches and rings to monitor physiology and sleep patterns (e.g., heart-rate, heart-rate variability, sleep duration). Participants reported their loneliness feeling multiple times a day through a questionnaire app on their phone. Using the data collected from their devices, we trained a random forest machine learning based model to detect loneliness levels. We found support for loneliness prediction using a multi-device and fully-objective approach. Furthermore, behavioral data collected by smartphones generally were the most important features across all participants. The study provides promising results for using objective data to monitor mental health indicators, which could provide a continuous and uninterrupted source of information in mental healthcare applications.

Community support, social isolation and older adults' life satisfaction: evidence from a national survey in China

OBJECTIVES

Despite the recognized importance of community social service and community built facility for enhancing older adults' life satisfaction, the mechanisms underlying their relationship have not been thoroughly examined. This study aims to complement the existing knowledge by investigating the mediating role of social disconnectedness and loneliness in the association between community support and life satisfaction among older adults.

METHODS

Using data from the 2018 China Longitudinal Aging Social Survey, the study analyzes responses from 9,874 Chinese older adults (mean age = 71.30 years, SD = 7.30). We conducted descriptive statistics and Pearson's correlation to explore the variables. This study also used Mplus 8.0 to conduct a path analysis model that evaluated both the direct and indirect effects of community social service and built facility on life satisfaction. Social disconnectedness and loneliness were included as mediating variables in this model.

RESULTS

The present study results show that both community social service and community built facility are positively associated with life satisfaction among older adults, and community social service is more imporatant for enhancing the life satisfaction. In addition, these associations are mediated by social disconnectedness and loneliness.

CONCLUSION

Our research suggests that strengthening community social service programs and improving the built environment can reduce social disconnectedness and loneliness among older adults, ultimately enhancing their life satisfaction. Specifically, policymakers can invest in targeted interventions to enhance social connectedness and reduce loneliness, with the goal of improving the overall well-being of older adults.

Well-designed manufacturing work improves some cognitive abilities in individuals with cognitive impairments

Introduction

Employment is recognized as a fundamental human right, which correlates with better physical and mental health. Importantly, well-designed work, which considers the physical, social, and psychological impacts of work, can serve to enhance the cognitive abilities of workers. Although often overlooked, work for individuals with disabilities, including cognitive impairments, is equally important for their physical and mental well-being. What has not been established, however, is whether well-designed work can also enhance the cognitive abilities of individuals with cognitive impairments.

Methods

Using a longitudinal study design, we investigated the impact of well-designed work on the cognitive abilities of 60 participants (operators) at the AMIPI Foundation factories, which employ individuals with cognitive impairments to produce electrical cables and harnesses for the automobile industry. The same operators were assessed at three different time points: upon hiring (n = 60), and after working in the factory for 1 year (n = 41, since 19 left the factory) and 2 years (n = 28, since 13 more left the factory). We used five cognitive tests evaluating: (1) finger and manual dexterity, bimanual dexterity, and procedural memory using the Purdue Pegboard; (2) sustained and selective attention using the Symbol Cancellation Task; (3) short- and long-term declarative verbal memory and long-term verbal recognition memory using Rey's Audio-Verbal Learning Test; (4) short- and long-term visual recognition memory using the Continuous Visual Memory Test; and (5) abstract reasoning using Raven's Standard Progressive Matrices.

Results

We observed improvements in procedural memory, sustained and selective attention, and short- and long-term visual recognition memory after working in the factory for 1 or 2 years. We did not observe improvements in finger or manual dexterity or bimanual dexterity, nor short- or long-term declarative verbal memory or verbal recognition memory, nor abstract reasoning.

Discussion

We conclude that, in addition to improving physical and mental well-being, well-designed manufacturing work can serve as a training intervention improving some types of cognitive functioning in individuals with cognitive impairments.

A longitudinal study of factors associated with cognitive frailty in middle-aged and elderly population based on the health ecology model

BACKGROUND

Cognitive frailty (CF) is an important geriatric syndrome and is reversible. It is crucial to develop preventive interventions for CF. We aimed to explore the associations between CF and its associated factors in Chinese aged 45 years and above.

METHODS

Based on the available data of 3 waves in China Health and Retirement Longitudinal Study from 2011 to 2015, 16,071 individuals aged 45 years and above from 3 waves were included. Based on the health ecology model, the associated factors were classified as downstream, midstream and upstream factors. Generalized hierarchical linear model including time level, individual level, and province level was applied to analyze the associations between factors and CF.

RESULTS

Multilevel factors have different effects on physical and cognitive function. In the downstream, old age, female, underweight, chronic diseases, and depression were risk factors of reversible CF and potentially reversible CF, and overweight was their protective factor. In the midstream, short or long night sleep duration was their risk factor, and > 30 and ≤ 60 min afternoon naps, alcohol drinking, and participation in social activities were their protective factors. In the upstream, living in rural areas was their risk factor, and high educational level, household consumption and GDP per capita were their protective factors.

CONCLUSIONS

Physical function and cognitive function are affected differently by multiple factors. The occurrence and development of physical frailty and cognitive impairment may have some common mechanisms. CF can be influenced by multilevel factors, and multilevel and comprehensive management of CF should be achieved.

KEY POINTS

Cognitive frailty was correlated with multilevel factors, including downstream, midstream, and upstream factors. It is crucial to focus on individual interventions such as physiological factors, psychological factors and health behaviors, especially the elderly, women and those with depression. Socioeconomic status was associated with the lower prevalence of cognitive frailty.

Social isolation and cognitive function in patients with schizophrenia: A two years follow-up study

Cognitive impairment is a core characteristic of schizophrenia. Social isolation has been linked to impaired cognitive function among the general population. In this longitudinal study, we examined the association between social isolation and cognitive function among inpatients with schizophrenia. Two waves of data (2019 and 2021) were collected from chronic psychiatric wards. A total of 166 inpatients completed all measurements at baseline and follow-up. Social isolation was measured by incorporating the frequency of social contact and participation, while cognitive functions were assessed by the Taiwan version of the Montreal Cognitive Assessment (MoCA-T). We used multiple linear regression to evaluate the link between baseline social isolation and cognitive function. For the total sample, social isolation was significantly related to poor language abilities (β = -0.17, p = 0.013) and delayed recall (β = -0.15, p = 0.023). Sex-stratified analysis showed that social isolation was significantly related to poor global cognitive function (β = -0.14, p = 0.021) and domain-specific cognitive functions including language abilities (β = -0.26, p = 0.003) and delayed recall (β = -0.19, p = 0.045) in male inpatients. No significant association was found between social isolation and global cognitive function or any cognitive domain (all ps > 0.05) for females. All associations were independent of loneliness and other covariates. These findings suggested that social isolation could predict poor subsequent cognitive function in inpatients with schizophrenia, especially in males. Interventions aimed at enhancing social connections could potentially improve cognitive function in this population.

Association of social isolation and loneliness with the risk of hypertension in middle aged and older adults: Findings from a national representative longitudinal survey

BACKGROUND

Social isolation and loneliness have been proved to be associated with many adverse health outcomes, but their influence on hypertension remains unclear. This study aimed to assess the relationship of social isolation and loneliness with hypertension risk among middle-aged and older adults in China.

METHODS

We used data from the 2011 and 2015 waves of the China Health and Retirement Longitudinal Study. Participants were assessed for social isolation and loneliness at baseline, and hypertension was identified by self-report and blood pressure measurement at follow-up in 2015. Binary logistic regression analyses were conducted to assess the association of social isolation and loneliness with the risk of hypertension.

RESULTS

A total of 3711 residents were included. 13.7 % of the participants had high level of social isolation and 18.1 % felt lonely. During the four-year follow up period, 651 participants developed hypertension. People with high level of social isolation had an increased risk of hypertension (odds ratio [OR]: 1.40, 95 % confidence interval [CI]: 1.09-1.79). Similar results were found between social isolation score and hypertension risk (OR: 1.14, 95 % CI: 1.04-1.26). No significant association between loneliness and hypertension or any interaction effect of social isolation and loneliness on hypertension were observed.

LIMITATIONS

Limited by the structure of questionnaire, some of the information was derived by self-report, which may lead to recalling bias.

CONCLUSION

Social isolation, rather than loneliness was associated with hypertension for middle aged and older adults. Social support needs to be strengthened for hypertension prevention in community.

Sedentary Behavior and Physical Frailty Among Rural Older Adults in China: The Moderating Effect of Social Isolation

OBJECTIVES

Few studies have explored the mechanisms underlying the relationship between sedentary behavior and physical frailty. The aim of this study was to investigate the moderating effect of social isolation on the association between sedentary behavior and physical frailty among older adults in rural China.

DESIGN

Cross-sectional study.

SETTING AND PARTICIPANTS

Data were from 3238 individuals aged ≥60 years from rural areas in China.

METHODS

Binary logistic regression was used to explore the association between sedentary behavior and physical frailty and the moderating effect of social isolation.

RESULTS

The prevalence of physical frailty was 18.7% among the older adults, and 17.0% of them were sedentary for ≥8 h/d. Compared with older adults with sedentary behavior for <4 h/d, participants with sedentary behavior for ≥8 h/d were more likely to suffer from physical frailty [odds ratio (OR), 2.26; 95% CI, 1.57-3.27]. We found that social isolation may aggravate this relationship (OR, 3.31; 95% CI, 2.06-5.32), especially for rural older adults who were sedentary for ≥8 h/day.

CONCLUSION AND IMPLICATIONS

More sedentary behavior was associated with higher risk of physical frailty, which was especially apparent among older adults with social isolation, suggesting that sedentary older people who experienced social isolation were more vulnerable to physical frailty. Decreasing sedentary behavior in older adults and encouraging them to participate in interactive social activities could help prevent physical frailty.

Intergenerational reciprocity and WHO function ability domains predict loneliness in older Chinese adults

OBJECTIVES

To examine loneliness in old age and whether intergenerational reciprocity and WHO functional ability predicted loneliness.

METHODS

Using the China Health and Retirement Longitudinal Study Wave 4 (2018) database (CHARLS), logistic regression models were adopted to investigate the relationships.

RESULTS

The prevalence of loneliness was 28% in older people in China. Corresponding to the five domains of functional abilities, providing financial support to adult children (adj. OR 0.83, 95% CI 0.70-0.99), self-perceived health (adj. OR 1.30, 95% CI 1.19-1.41), having a retirement pension (adj. OR 0.73, 95% CI 0.57-0.93), the ability to decide on taking medications (adj. OR 1.32, 95% CI 1.10-1.58), as well as being able to get up from a chair (adj. OR 1.15, 95% CI 1.02-1.3), and having paid work (adj. OR 0.72, 95% CI 0.54-0.95) were associated with less loneliness. On the contrary, infrequent contact (once a month) with adult children (adj. OR 1.18, 95% CI 1.01-1.38), troubling body pain (adj. OR 1.16, 95% CI 1.10-1.23) and falling since the last interview (adj. OR .23, 95% CI 1.04-1.45) were positively associated with loneliness.

CONCLUSIONS

In this study, functional abilities of meeting basic needs, making decisions, being mobile and contributing to the support of adult children and society were protective factors for experiencing loneliness in late life. We need to rethink interventions for addressing loneliness in the context of healthy ageing and specific cultural values, taking into account not only providing services to older adults but also supporting them to gain values by contributing to society.

Association between solid cooking fuel use and dementia in older Chinese adults: the mediating effect of depression

This study aimed to explore the association between household solid cooking fuel use and dementia prevalence and the mediating effect of depression on this association. A total of 3404 (2018) and 1379 (2015 to 2018) older participants (≥65) from the China Health and Retirement Longitudinal Study (CHARLS) were enrolled in the cross-sectional and retrospective longitudinal analyses, respectively. The results showed that solid cooking fuel use was associated with an increased dementia prevalence (adjusted OR = 1.44) from 2015 to 2018. The indirect effect of depression on this association explained 7.14% and 13.11% variances in the cross-sectional and longitudinal mediating model, respectively. Thus, household solid cooking fuel use is a risk factor for the development of dementia, and depressive symptoms partially accounted for this association. The use of improved cookstoves and clean fuel in households and air cleaners and early intervention in depression may reduce the incidence of dementia.

Social Isolation, Physical Activity, and Subsequent Changes in Cognition Among Middle- and Older-Aged Adults: Results From the Canadian Longitudinal Study on Aging

OBJECTIVE

The objectives of this study were to a) evaluate associations between social isolation and change in cognition over a 3-year period, and b) evaluate whether physical activity mediates the association between social isolation and cognition change.

METHODS

Using baseline and follow-up 1 data from the Canadian Longitudinal Study on Aging, latent change score models, incorporating direct and indirect pathways, were constructed to estimate the indirect effect of social isolation on cognitive change through physical activity. Multigroup models were constructed based on age group (45-65 versus 65+ years) and sex to allow for varying estimates across age and sex. The final analytic sample included 51,338 participants.

RESULTS

Indirect effects of social isolation on cognition through physical activity were evident in men and women 65+ years old for memory change ( = -0.005 [99.9% confidence interval = -0.007 to -0.002], p < .001 in both groups) and in male adults 65+ years old for executive function change ( = -0.01 [99.9% confidence interval = -0.02 to -0.006], p < .001). Statistically significant indirect effects were not observed for adults between 45 and 65 years old.

CONCLUSIONS

Social isolation is associated with diminished physical activity, and in turn, diminished physical activity is associated with decline in memory in older women and men, with larger declines in executive function in older men. Public health initiatives to promote physical activity-perhaps incorporating social interaction-among older adults experiencing social isolation could be one way to mitigate the negative impact of social isolation on cognitive health.

Utility of Goal Attainment Scaling (GAS) in evaluating a multicomponent exercise programme for community-dwelling pre-frail older adults

OBJECTIVES

This study aimed to investigate the effectiveness of Goal Attainment Scaling (GAS) in assessing an intervention for pre-frail senior citizens. Additionally, the study aimed to explain how the GAS goals were established based on the International Classification of Functioning, Disability and Health (ICF) categories, including body function, activity and participation and environmental factors.

METHODS

In this study, 220 pre-frail older adults were randomly selected to participate in a controlled trial. The intervention group engaged in multicomponent exercise three times a week, once at a community health service location and twice at home. The control group received advice on physical activity but did not have supervised exercise. Participants in both groups selected individualised GAS goals from 23 goals developed based on ICF by focus group discussion. The study used generalised estimating equations to analyse the differences between the groups.

RESULTS

The study included 144 participants, 72 in the exercise group and 72 in the control group. The top three individualised goals for all participants were vestibular functions (53.5%), pain management (43.1%) and lifting and carrying objects (31.9%). Both groups saw a significant increase in GAS scores at week 8 and week 24 of the intervention (p<0.05), but the exercise group showed a more significant improvement (p<0.05). The participants living alone were associated with lower postintervention improvements in the GAS scores. In contrast, the participants who were using a smartphone were likely to get higher postintervention improvements in the GAS scores.

CONCLUSIONS

GAS can be a valuable tool for setting and evaluating individualised and meaningful goals in body functions, activity and participation and environmental factors. The multicomponent exercise interventions can help pre-frail older adults achieve their expected goals as measured by the GAS.

The risk of developing dementia in the COVID-19 pandemic; a cohort study

OBJECTIVES

The effects of the COVID-19 pandemic on cognitive decline are not fully understood. Higher social activity and relationships have been associated with decreased risk of dementia. We hypothesised that risk of transition to dementia would increase after the start of the first national lockdown.

METHODS

We obtained data from the Brains for Dementia (BDR) cohort, which has collected roughly annual data on 3726 older adults with and without dementia since 2008. Data continued to be collected during the lockdowns, although by telephone and/or video call instead of in person. Individuals diagnosed with dementia at study entry were excluded from this study as were individuals with only one visit. Cognitive status was classified using the Clinical Dementia Rating (CDR) global score. Poisson regression with cubic splines to account for differences in age was used to compare the incidence of dementia before and after March 1st 2020.

RESULTS

Out of 2242 individuals, 208 individuals developed dementia before and 50 developed dementia after 01/03/20. The incidence rate ratio of developing dementia after 01/03/20 was 0.847 (0.538-1.335) p = 0.570. In our secondary analysis we found that the positive association between mild cognitive impairment (MCI) and dementia incidence decreased after 1/3/20 (interaction effect p = 0.031).

CONCLUSION

The incidence of dementia as defined using the CDR global score did not change significantly after the first lockdown began, but we found evidence that lockdown decreased the positive association between MCI and dementia incidence. This may reflect that individuals were progressing to dementia more rapidly and thus missing the MCI stage or that assessing patients over the phone made diagnosing MCI more challenging.

The longitudinal bidirectional association between sarcopenia and cognitive function in community-dwelling older adults: Findings from the China Health and Retirement Longitudinal Study

Background

Although an association between sarcopenia and cognitive function has been demonstrated, the directional association remains unclear. The present study aimed to evaluate the longitudinal reciprocal relationship and identify the possible temporal sequence between sarcopenia and cognitive function in older Chinese adults.

Methods

Data were collected from the China Health and Retirement Longitudinal Study (CHARLS) baseline survey in 2011 and the follow-up survey in 2015. Cognitive function was measured by episodic memory and executive function. Sarcopenia status (non-sarcopenia, possible sarcopenia and sarcopenia) was defined based on the Asian Working Group for Sarcopenia 2019 criteria. Linear regression analysis and ordinal logistic regression analysis were employed to investigate the relationship between baseline sarcopenia status and follow-up cognition, as well as the association of baseline cognition with follow-up sarcopenia status, respectively. A cross-lagged panel analysis was performed to simultaneously evaluate the bidirectional association and the strength of the temporal relationship.

Results

Of 2689 participants, the median age was 65.0 years and 1249 (46.5%) were female. After adjusting for potential confounders and baseline measurements, baseline sarcopenia status was dose-dependently associated with subsequent cognitive scores (β = -0.45; P for trend = 0.001), and baseline cognitive scores (in tertiles) were also dose-dependently associated with subsequent sarcopenia status (odds ratio (OR) = 0.86; P for trend = 0.017). The cross-lagged panel analysis indicated that the standardised effect size of sarcopenia status on cognitive function (β = -0.09; P < 0.001) is larger relative to the effect of cognitive function on sarcopenia status (β = -0.05; P = 0.019).

Conclusions

There is a longitudinal, bidirectional relationship between sarcopenia status and cognitive function in older Chinese adults. Sarcopenia is likely the driving force in these dynamic associations. These findings imply that interventions in either sarcopenia or cognitive decline may have the ability to generate reciprocal benefits over time. More research is warranted to confirm these findings and to further elucidate underlying causal pathways.

Gender-specific moderating role of abdominal obesity in the relationship between handgrip strength and cognitive impairment

BACKGROUND & AIMS

Both low handgrip strength (HGS) and abdominal obesity (AO) are associated with cognitive impairment. However, it remains unclear whether low HGS and AO interact to affect cognition, and whether the synergistic effect varies by gender. This study aimed to examine whether the association between low HGS and incident cognitive impairment was moderated by AO among Chinese older men and women.

METHODS

We used the data of participants (≥60 years) from four waves (2011-2018) of the China Health and Retirement Longitudinal Study. We defined low HGS as the maximal HGS of <28 kg in men and <18 kg in women, and AO as waist circumference of ≥90 cm for men and ≥80 cm for women. Cognitive impairment was defined as a global cognitive score in the lowest 10th percentile. For each gender, we used subdistribution hazards model to estimate subdistribution hazard ratios (SHRs) for the association of low HGS and AO with incident cognitive impairment, treating mortality as the competing event and controlling for other covariates. Multiplicative interaction was assessed through a cross-product interaction term of low HGS and AO in the model. Additive interaction between low HGS and AO was evaluated by calculating the relative excess risk due to interaction (RERI) and attributable proportion due to interaction (AP).

RESULTS

We included 3704 participants (Mean age: 66.9 ± 5.81; 54.9% male). During the 7-year follow-up, 1133 events of interest occurred (731 cognitive impairments and 402 deaths). Incidence rates of cognitive impairment and mortality were 4.1 (95% CI: 3.8 to 4.4) and 2.2 (95% CI: 2.0 to 2.5) per 100 person-years. There were positive multiplicative (SHR for the product term = 1.974, 95% CI: 1.114 to 3.500) and additive interactions (RERI = 1.056, 95% CI: 0.027 to 2.086, AP = 0.454, 95% CI: 0.158 to 0.750) of low HGS and AO on the risk of cognitive impairment among older men. Male participants with both low HGS and AO showed an increased risk of cognitive impairment (SHR = 2.325, 95% CI: 1.498 to 3.609) compared with those without either. There was no evidence of interaction among older women (SHR for the product term = 1.151, 95% CI: 0.725 to 1.825; RERI = 0.044, 95% CI: -0.524 to 0.613; AP = 0.039, 95% CI: -0.458 to 0.536).

CONCLUSIONS

Low HGS and AO may interact to synergistically increase the risk of cognitive impairment among Chinese older men. Screening the highest-risk subpopulation, who may benefit most from neurocognitive prevention strategies, may maximize potential public health gains.

Daytime napping, biological aging and cognitive function among middle-aged and older Chinese: insights from the China health and retirement longitudinal study

Objective

The complicated association of daytime napping, biological aging and cognitive function remains inconclusive. We aimed to evaluate the cross-sectional and longitudinal associations of daytime napping and two aging measures with cognition and to examine whether napping affects cognition through a more advanced state of aging.

Methods

Data was collected from the China Health and Retirement Longitudinal Study. Napping was self-reported. We calculated two published biological aging measures: Klemera and Doubal biological age (KDM-BA) and physiological dysregulation (PD), which derived information from clinical biomarkers. Cognitive z-scores were calculated at each wave. Linear mixed models were used to explore the longitudinal association between napping, two aging measures, and cognitive decline. Mediation analyses were performed to assess the mediating effects of biological age acceleration on the association between napping and cognition.

Results

Participants aged over 45 years were included in the analyses. Non-nappers had greater KDM-BA and PD [LS means (LSM) = 0.255, p = 0.007; LSM = 0.085, p = 0.011] and faster cognitive decline (LSM = -0.061, p = 0.005)compared to moderate nappers (30-90 min/nap). KDM-BA (β = -0.007, p = 0.018) and PD (β = -0.034, p < 0.001) showed a negative association with overall cognitive z scores. KDM-BA and PD partially mediated the effect of napping on cognition.

Conclusion

In middle-aged and older Chinese, compared to moderate nappers, non-nappers seem to experience a more advanced state of aging and increased rates of cognitive decline. The aging status possibly mediates the association between napping and cognition. Moderate napping shows promise in promoting healthy aging and reducing the burden of cognitive decline in Chinese middle-aged and older adults.

The effects of loneliness and social isolation on cognitive impairment-free life expectancy in older adults

OBJECTIVES

This article aimed to examine the effects of social connection comprising loneliness and social isolation on cognitive impairment-free life expectancy (CIFLE).

METHODS

Data on 28,563 older adults (aged 65+) were drawn from the Chinese Longitudinal Healthy Longevity Survey with a median follow-up of 4.00 years. Multistate Markov models were used to estimate the independent and joint effects of social connection with CIFLE. Cognitive impairment was measured by the modified Mini-Mental State Examination.

RESULTS

For men and women, respectively, reduced CIFLEs at age 65 associated with loneliness were 0.95 (95% CI: 0.41-1.48) and 1.35 (95%: CI 0.77-1.90) years, and those associated with social isolation were 2.23 (95% CI: 1.67-2.78) and 2.49 (95% CI: 1.67-3.30) years. Compared with those with neither loneliness nor social isolation ('neither' group), older adults at age 65 with both loneliness and social isolation ('both group') lost CIFLEs of 2.68 (95% CI: 1.89-3.48) and 3.51 (95% CI, 2.55-4.47) years for men and women, respectively. Similar patterns were observed in the oldest-old adults (age 85 or over). A growth trend transpired in the difference of the proportion of the remaining CIFLE between 'neither' group and 'both' group with age.

CONCLUSION

Loneliness and social isolation are associated with decreased CIFLE in older Chinese adults. Policy makers and the public must be informed that early identification and management of loneliness and social isolation, especially when coexisting, are crucial.

Social Isolation, Sleep Disturbance, and Cognitive Functioning (HRS): A Longitudinal Mediation Study

BACKGROUND

Social isolation is prevalent and associated with dementia, yet the directionality and mechanisms are less understood. This study examined the association between social isolation and cognitive functioning and explored the mediating role of sleep disturbance on the social isolation-cognition relationship.

METHODS

Data from 5 753 dementia-free Americans aged ≥50 of 2006 (T1), 2010 (T2), and 2014 (T3) waves of the Health and Retirement Study. Social isolation was measured by the Steptoe Social Isolation Index. Cognitive functioning was measured by the Telephone Interview of Cognitive Status. Sleep disturbance was measured with the modified Jenkins Sleep Scale. We used cross-lagged panel models to determine the associations between social isolation, sleep disturbance, and cognitive functioning.

RESULTS

Social isolation is significantly associated with subsequent cognitive functioning (T1 to T2: β = -0.055, standard error [SE] = 0.014, p < .001; T2 to T3: β = -0.044, SE = 0.016, p < .001). Lower cognitive functioning is significantly associated with greater subsequent social isolation (T1 to T2: β = -0.101, SE = 0.020, p < .001; T2 to T3: β = -0.058, SE = .011, p < .001). Sleep disturbance at T2 partially mediated the effect of social isolation (T1) on cognitive functioning (T3), accounting for 6.2% of the total effect (β = -0.003, SE = 0.001, p < .01).

CONCLUSIONS

Social isolation may deteriorate cognitive functioning and vice versa. The association between social isolation and cognition is partially explained by sleep disturbance.

Sociodemographic features associated with the MoCA, SPPB, and GDS scores in a community-dwelling elderly population

BACKGROUND

An accurate evaluation of cognitive function, physical health, and psychological health is fundamental for assessing health problems in the elderly population, and it is important to identify the necessity of early therapeutic intervention. The objective of this study was to evaluate the states of mental and physical functions and to investigate the relationships between sociodemographic features and these functions in a community-dwelling elderly population.

METHODS

This community-based cross-sectional study was conducted in a suburban district of Shanghai, China. A total of 1025 participants aged 60-89 years underwent investigations of demographic and lifestyle features and a multidimensional geriatric evaluation comprising the Montreal Cognitive Assessment (MoCA), Short Physical Performance Battery (SPPB), and Geriatric Depression Scale (GDS).

RESULTS

The results of the multivariate linear regression models demonstrated that the MoCA and SPPB scores decreased with advancing age (all P < 0.01). However, the GDS score did not exhibit an age-related decrease (P = 0.09). Both sex and living alone influenced the MoCA score (P < 0.01 and P = 0.04, respectively), SPPB score (P < 0.01 and P = 0.04, respectively), and GDS score (P < 0.01 and P < 0.01, respectively). A higher education level was related to better MoCA and SPPB scores (all P < 0.01). Furthermore, age and sex had interactive effects on the MoCA score (P = 0.03) and SPPB score (P < 0.01). The kernel-weighted local polynomial smoothing curves exhibited similar trends.

CONCLUSIONS

It is imperative to develop a more sensitive evaluation of physical function, and to encourage various intellectually and emotionally stimulating social activity strategies to promote healthy aging, especially in elderly women and those living alone who have a low education level.

Later-life depressive symptoms during the Covid-19 pandemic: Investigations of individual, cumulative, and synergistic effects of social isolation

OBJECTIVES

This study examines associations between social isolation and depressive symptoms among Hong Kong Chinese adults aged 65 and older by investigating the distinct effects of individual indicators, cumulative index, and typologies of social isolation during the Covid-19 pandemic.

METHODS

We used a sample of 260 older adults from a cross-sectional, city-wide online survey targeting 1,109 aged 45+ adults through purposive sampling. Seven indicators of social isolation (not married; living alone; not engaging in social/organizational activities; no social contact with friends or families; lack of family and friends networks; loneliness) using Cornwell & Waite's framework were selected to construct three unique types of social isolation measures. We used latent class analysis (LCA) and regression models to examine the effects of varied typologies of social isolation on depressive symptoms.

RESULTS

Individual model of social isolation showed that lack of social contact and feeling lonely were significant predictors of depressive symptoms. A strong linear-trend gradient effect of cumulative social isolation on depressive symptoms was also observed. The LCA model identified four typologies of social isolation (socially isolated; living alone but socially engaged; married but lacking social ties, and not socially isolated); those in the 'socially isolated' and 'married but lacking social ties' groups had the most depressive symptoms.

CONCLUSION

Three operationalizations of social isolation demonstrated different utilities and implications in assessing the impacts of social isolation on depressive symptoms. Social contacts and loneliness, rather than living status or other characteristics of isolation, were the factors most strongly associated with depressive symptoms. Support programs should target lonely older adults who lack social engagement opportunities, as they are at increased risk of depression.

Are loneliness and social isolation equal threats to health and well-being? An outcome-wide longitudinal approach

The detrimental effects of loneliness and social isolation on health and well-being outcomes are well documented. In response, governments, corporations, and community-based organizations have begun leveraging tools to create interventions and policies aimed at reducing loneliness and social isolation at scale. However, these efforts are frequently hampered by a key knowledge gap: when attempting to improve specific health and well-being outcomes, decision-makers are often unsure whether to target loneliness, social isolation, or both. Filling this knowledge gap will inform the development and refinement of effective interventions. Using data from the Health and Retirement Study (13,752 participants (59% women and 41% men, mean [SD] age = 67 [10] years)), we examined how changes in loneliness and social isolation over a 4-year follow-up period (from t0:2008/2010 to t1:2012/2014) were associated with 32 indicators of physical-, behavioral-, and psychosocial-health outcomes 4-years later (t2:2016/2018). We used multiple logistic-, linear-, and generalized-linear regression models, and adjusted for sociodemographic, personality traits, pre-baseline levels of both exposures (loneliness and social isolation), and all outcomes (t0:2008/2010). We incorporated data from all participants into the overall estimate, regardless of whether their levels of loneliness and social isolation changed from the pre-baseline to baseline waves. After adjusting for a wide range of covariates, we observed that both loneliness and social isolation were associated with several physical health outcomes and health behaviors. However, social isolation was more predictive of mortality risk and loneliness was a stronger predictor of psychological outcomes. Loneliness and social isolation have independent effects on various health and well-being outcomes and thus constitute distinct targets for interventions aimed at improving population health and well-being.

Aging to 24 months increased C57BL/6J mouse social sniffing and hippocampal Neto1 levels, and impaired female spatial learning

Understanding how natural aging impacts rodent performance in translational behavior tests is critical to teasing apart impairments due to age-related decline from neurodegenerative disorder modeling. Reduced neuropilin and tolloid-like 1 (NETO1), an accessory protein of ionotropic glutamate receptors involved in synaptic plasticity, was associated with Alzheimer's disease, yet aging effects on Neto1 remain unclear. For these reasons, our goal was to characterize how Neto1 expression corresponded with social, repetitive, and spatial learning behaviors and stress response across the C57BL/6J mouse lifespan. We measured social preferences in three-chamber tests, and motor stereotypies by marble burying. Cognitive flexibility is typically assessed in the Morris water maze (MWM), wherein C57BL/6J mice exhibit deficits with age. However, fatigue or locomotor impairment may confound interpretation of MWM performance. Therefore, we used a less arduous water T-maze (WTM) to compare spatial learning flexibility in 2, 9-15, and 24-month-old male and female mice to test the hypothesis that deficits would emerge with age. In both sexes, 9-15-month-olds made more chamber entries during social preference tests, while 2-month-olds did less social sniffing than aged mice. No age or sex differences emerged in marble burying or serum corticosterone measurements. In 24-month-olds hippocampal Neto1was increased relative to 2-month-olds, and male cognitive flexibility was strong, while spatial learning and reversal learning of 24-month-old females was impaired in WTM irrespective of Neto1 expression. The WTM is a useful alternative assessment for cognitive flexibility deficits in aged mice, and the role of hippocampal Neto1 in promoting social sniffing is of interest.

Physical Mobility, Social Isolation and Cognitive Function: Are There Really Gender Differences?

OBJECTIVE

This study aimed to examine the mediating role of social isolation between physical mobility and cognitive function, and whether there are gender differences in the above mediating effects among Chinese older adults.

METHODS

This is a prospective and cohort study. We obtained data from the 2011 (Time 1, T1), 2015 (Time 2, T2) and 2018 (Time 3, T3) waves of China Health and Retirement Longitudinal Study, including 3,395 participants aged 60 years or above. Cognition was evaluated by Telephone Interview of Cognitive Status, words recall, and figure drawing, which was widely used in previous research. We used a cross-lagged model to test the hypothesis that social isolation mediated the association between physical mobility and cognitive function among Chinese older adults.

RESULTS

The total effects of T1 physical mobility limitations on T3 cognitive function (β = -0.055, bootstrap p < 0.001) were significantly negative. Social isolation played a mediating role among both males and females (male: β = -0.008, bootstrap p = 0.012; female: β = -0.006, bootstrap p = 0.023), demonstrating that the mediating effect of social isolation between physical mobility and cognitive function was not gender specific.

CONCLUSION

This study confirmed that social isolation mediated the association between physical mobility and cognitive function among both Chinese male and female older adults. These findings indicate that reversing social isolation can be a priority intervention target for cognitive decline prevention and promote successful ageing, particularly among older adults with impaired physical mobility.

Effects of long-term individual housing of middle-aged female Octodon degus on spatial learning and memory in the Barnes maze task

Introduction

Prolonged social isolation is a form of passive chronic stress that has consequences on human and animal behavior. The present study was undertaken to elucidate whether the long-term isolation would precipitate age-related changes in anxiety and spatial learning and memory in degus.

Methods

We investigated the effects of long-term social isolation on anxiety levels in the light-dark test, and spatial orientation abilities in the Barnes maze. Middle-aged female Octodon degus were allocated to either group-housed (3 animals per cage) or individually-housed for 5 months.

Results

Under this experimental condition, there were no significant group differences in the anxiety level tested in the light-dark test and in the motivation to escape from the Barnes maze. There were no significant differences in cortisol levels between individually- and group-housed animals. On the last acquisition training day of spatial learning, individually- housed animals had a significantly higher number of correct responses and a smaller number of reference and working memory errors than the group-housed animals. In addition, isolated animals showed a tendency for reference and working memory impairment on the retention trial, while group-housed degus showed improvement in these parameters.

Discussion and conclusion

The present study indicates that prolonged social isolation during adulthood in female degus has a dual effect on spatial orientation. Specifically, it results in a significant improvement in acquisition skills but a slight impairment in memory retention. The obtained cognitive changes were not accompanied by modification in anxiety and cortisol levels.

Association of social isolation and cognitive performance: a longitudinal study using a four-wave nationwide survey

BACKGROUND

This study aimed to examine the bidirectional relationship between social isolation and cognitive performance among Chinese middle-aged and older adults.

METHODS

We used four waves of data from the China Health and Retirement Longitudinal Study. A latent growth model (LGM) was applied to examine the association between social isolation and cognitive performance across different characteristics.

RESULTS

In the analysis, we ultimately included 9,367 participants after excluding respondents with missing key variables. Social isolation and cognitive performance showed significant differences across time. After adjusting for the confounders, there was a significant association between higher social isolation and poor cognitive performance (β = -1.38, p < 0.001), and higher levels of social isolation resulted in a more pronounced decline in cognition over time (β = 0.17, p < 0.001). Additionally, the path coefficient between the initial level of cognition at baseline and the slope of social isolation was - 0.07 (p < 0.001) and 0.01 (p = 0.021), respectively. For the correlation between slopes, our study found that females' cognition scores were more susceptible to social isolation (β = - 2.78, p < 0.001). Similarly, regarding cognition scores, the influence of social isolation was greater among people with education below the primary level (β = - 2.89, p = 0.002) or a greater number of chronic diseases (β = - 2.56, p = 0.001).

CONCLUSION

Our findings support the bidirectional association between social isolation and cognition. Specifically, higher baseline social isolation and its rate of increase over time contribute to an intensification of cognitive decline at follow-up. Besides, poorer cognitive performance predicted higher social isolation.

Constructing the concept of healthy ageing and examining its association with loneliness in older adults

BACKGROUND

World Health Organization (WHO) has defined healthy ageing by highlighting five functional ability domains to (meet basic needs, make decisions, be mobile, build and maintain relationships, and contribute to society), which also emphasized the importance of addressing loneliness as priorities within United Nations Decade of Healthy Ageing initiative. However, the level and determinants of healthy ageing and its association with loneliness are rarely examined. This study aimed to construct a healthy ageing index to verify the WHO healthy ageing framework, measure five domains of functional ability of older adults and examine the relationship between functional ability domains and loneliness.

METHODS

A total of 10,746 older adults from the 2018 China Health and Retirement Longitudinal Study (CHARLS) were included. A healthy ageing index ranging from 0 to 17 was constructed using 17 components related to functional ability domains. Univariate and multivariate logistic regression analyses were utilized to determine the association between loneliness and healthy ageing. The STROBE guidelines with the RECORD statement for observational studies using routinely collected health data were observed.

RESULTS

The factor analysis verified the five functional ability domains for healthy ageing. After adjusting for confounders, being mobile, building and maintaining relationships, and learning, growing and making decisions were significantly associated with lesser loneliness among participants.

CONCLUSIONS

The healthy ageing index of this study can be utilized and further modified with respect to large-scale research with relevant healthy ageing topics. Our findings will support healthcare professionals to provide patient-centered care when identifying their comprehensive abilities and needs.

Social distancing, emotional suffering, and cognitive performance in mature and older adults: a literature review

Variables related to social distancing can have negative effects on the emotional well-being and cognition of adults and the elderly.

Objective

The aim of this study was to analyze the available studies that address the relationship between situations of social distancing, socioemotional aspects, and cognition in the lives of mature and older adults.

Methods

A literature review study was carried out between December 2021 and January 2022, involving the SciELO, PubMed, and ScienceDirect databases, with studies published between February 2018 and December 2021.

Results

A total of 754 studies were identified, and after selection, 18 were included. Notably, 16 showed significant effects of social distancing on cognition and socioemotional aspects, that is, the greater the social distancing, the lower the capacity for cognitive performance and the higher the index of symptoms of depression and anxiety, for example.

Conclusions

Greater engagement in social activities and a closer contact with friends and family are protective factors against symptoms of depression and anxiety and cognitive decline.

Comparing the role of social connectivity with friends and family in depression among older adults in China: evaluating the moderating effect of urban-rural status

Background

Social connectivity and support can reduce depressive symptoms. Few studies have examined urban-rural differences in the relationship between social support and depressive symptoms in the context of urbanization for Chinese older adults. The overall aim of this study is to examine urban-rural differences in the relationship between family support and social connectivity on depression among Chinese older adults.

Methods

This cross-sectional study used data from the 2010 Sample Survey on Aged Population in Urban/Rural China (SSAPUR). Depressive symptoms were measured using the Geriatric Depression Scale short-form (GDS-15). Family support was measured by structural, instrumental, and emotional support. Social connectivity was measured using the Lubben Social Network Scale-6 (LSNS-6). Descriptive analysis was conducted using chi-square and independent t-tests to examine urban-rural differences. Adjusted multiple linear regressions were conducted to examine the moderating effect of urban-rural status on the association between types of family support and social connectivity with depressive symptoms.

Results

In rural areas, respondents who felt their children exhibited filial piety (β = -1.512, p < 0.001) and had more social connectivity with family (β = -0.074, p < 0.001) were more likely to report fewer depression symptoms. In urban areas, respondents who received instrumental support from their children (β = -1.276, p < 0.01), who thought their children exhibited filial piety (β = -0.836, p < 0.01), and who had more social connectivity with friends (β = -0.040, p < 0.01) were more likely to report fewer depression symptoms. In the fully adjusted regression model, social connectivity with family was associated with decreased depressive symptoms, although to a lesser degree among urban-dwelling older adults (urban-rural interaction effect, β = 0.053, p < 0.05). Social connectivity with friends was similarly associated with decreased depressive symptoms, although this effect was greater among urban-dwelling older adults (urban-rural interaction effect, β = -0.053, p < 0.05).

Conclusion

The results of this study suggested that older adults both in rural and urban areas with family support and social connectivity were associated with fewer depression symptoms. Differences observed in the role of family and friend social connectivity by urban-rural status may provide practical information for developing targeted social support strategies for improving depressive symptoms among Chinese adults, and call for further mixed-methods research to disentangle mechanisms behind these differing associations.

Race and Apolipoprotein E-e4 Allele Status Differences in the Association Between Loneliness and Cognitive Decline

OBJECTIVE

This study aimed to examine race and apolipoprotein E-e4 allele (APOE-e4) status differences in the longitudinal associations between loneliness and cognitive decline.

METHODS

The study sample is composed of participants ( N = 7696, 64% Black participants and 36% White participants) from the Chicago Health and Aging Project, a population-based cohort study. Mixed-effects regression models were conducted to examine the longitudinal associations between loneliness on global cognitive function and individual tests of cognitive function. Models were also stratified by race and APOE-e4.

RESULTS

A greater percentage of Black participants (17%) reported loneliness at baseline visit compared with White participants (12%). Black and White participants who were lonely individuals had a similar rate of decline in global cognitive function at 0.075 (95% confidence interval [CI] = -0.082 to -0.068) standard deviation unit (SDU) per year for Black participants and at 0.075 (95% CI = -0.086 to -0.063) SDU per year for White participants. Lonely participants with APOE-e4 had a higher rate of global cognitive decline at -0.102 (95% CI = -0.115 to -0.088) SDU per year than for lonely participants without APOE-e4 at -0.052 (95% CI = -0.059 to -0.045) SDU per year.

CONCLUSIONS

The burden of loneliness and its relation to cognitive decline is higher among participants with APOE-e4 compared with those without APOE-e4. Loneliness is associated with cognitive decline in both Black and White participants.

Is there a correlation between sensory impairments and social isolation in middle-aged and older Chinese population? Cross-sectional and longitudinal evidence from a nationally representative survey

Purpose

The aim of this study is to investigate the cross-sectional and longitudinal associations between sensory impairments (SIs) including single vision impairment (SVI), single hearing impairment (SHI), and dual sensory impairments (DSI) with social isolation in the middle-aged and older Chinese population.

Methods

Data were obtained from the China Health and Retirement Longitudinal Survey (CHARLS). In total, 11,674 Chinese older adults aged over 45 were included at baseline 2011, and 6,859 participants who accomplished all four interviews from 2011 to 2018 were adapted for longitudinal analyses. Sensory status and social isolation measurements including social disconnectedness and self-perceived loneliness were collected. Assessment of social disconnectedness included the number of types of social activities in which they participated and the frequency of such participation. Loneliness referred to the subjective perception of loneliness. Other covariates included socio-demographic characteristics, medical conditions, and lifestyle-related factors. The impacts of baseline sensory status on social disconnectedness and loneliness were assessed using univariate and multivariate generalized linear models. A generalized linear model with generalized estimation equations (GEE) was used to assess the association between time-varying sensory statuses with social disconnectedness or loneliness over 8 years after being adjusted with multi-confounding factors.

Results

Participants with SIs had significantly higher levels of social disconnectedness and self-perceived loneliness, compared to those who were free of SI. All kinds of SIs were significantly associated with loneliness according to both cross-sectional and longitudinal data. The correlations between DSI and social disconnectedness or loneliness at baseline and over 8 years were also noticed. SHI was found to be significantly associated with both frequency and types of social activities according to cross-sectional data and with the frequency of social activity participation in longitudinal analysis. SVI was only associated with the types of social activities at baseline (all p-values &lt; 0.05).

Conclusion

Sensory impairments, especially dual sensory impairments, have explicitly detrimental effects on social isolation among the older Chinese population. Over time, single hearing impairment specifically jeopardizes their frequency rather than types of social activities participation.

Association between multimorbidity and memory-related diseases among middle-aged and older adults: Evidence from the China Health and Retirement Longitudinal Study

Objectives

This study aimed to examine the cross-sectional and longitudinal association between multimorbidity and memory-related diseases (MDs) among Chinese middle-aged and older adults.

Methods

This study included 8,338 subjects who participated in the China Health and Retirement Longitudinal Study (CHARLS). Logistic regression and Cox proportional hazards regression models were used to explore the association and effect of multimorbidity on MDs.

Results

The overall prevalence of MDs was 2.52%, and the mean multimorbidity number was 1.87. In a cross-sectional analysis, compared with the no multimorbidity group, groups of multimorbidity with four or more non-communicable diseases (NCDs) were more likely to have MDs (OR: 6.49, 95%CI: 4.35–9.68). Within 2.7 years of follow-up, 82 cases of MDs (1.12%) were reported, and participants with multimorbidity were more likely to have new-onset MDs than participants without multimorbidity (HR: 2.93, 95%CI: 1.74–4.96).

Conclusion

Multimorbidity is associated with MDs among Chinese middle-aged and older adults. This relationship gradually strengthens with the severity of multimorbidity, which indicates that early prevention for people with multimorbidity may reduce the risk of MDs.

Association of polypharmacy and motoric cognitive risk syndrome in older adults: A 4-year longitudinal study in China

BACKGROUND

Polypharmacy is related to motoric cognitive risk (MCR) syndrome is not fully understood. Therefore, our aim was to fill this gap in knowledge.

METHODS

This population-based prospective longitudinal study used data from the China Health and Retirement Longitudinal Study. It included 3827 dementia-free older adults (age >60 years) who were followed from 2011 to 2015. Data on subjective cognitive complaints, walking speed, and polypharmacy were reported by the participants. The cross-sectional relationship between polypharmacy and the MCR at baseline was examined using multinomial logistic regression, and Cox regression will be used to analyze the impact of polypharmacy on MCR over a four-year period.

RESULTS

At baseline, 492 (12.9%) participants had been diagnosed with MCR. With 4 years of follow-up, 304 (12.5%) were classified as having incident MCR. Controlling for microsystem factors, polypharmacy (OR: 1.273, 95 % CI: 1.051-1.541; p < .05) was associated with MCR at baseline and every unit increase in polypharmacy was linked to a 53.8% (HR:1.538, 95 % CI: 1.227-1.927; p < .001) increase more likely to developing incident MCR. They adjusted for meso/ exosystem and macrosystem factors, and these associations remained significant, coping resources are believed to have a role in the relationships between polypharmacy and MCR in older persons.

CONCLUSION

Polypharmacy is significantly associated with MCR incidence during 4 years of follow-up in older adults. Future studies should independently confirm this observation for potentially bringing clinical benefits to older people with polypharmacy.

The impact of loneliness and social isolation on the development of cognitive decline and Alzheimer's Disease

Alzheimer's Disease (AD) is the leading cause of dementia, observed at a higher incidence in women compared with men. Treatments aimed at improving pathology in AD remain ineffective to stop disease progression. This makes the detection of the early intervention strategies to reduce future disease risk extremely important. Isolation and loneliness have been identified among the major risk factors for AD. The increasing prevalence of both loneliness and AD emphasizes the urgent need to understand this association to inform treatment. Here we present a comprehensive review of both clinical and preclinical studies that investigated loneliness and social isolation as risk factors for AD. We discuss that understanding the mechanisms of how loneliness exacerbates cognitive impairment and AD with a focus on sex differences will shed the light for the underlying mechanisms regarding loneliness as a risk factor for AD and to develop effective prevention or treatment strategies.

The Buffering Role of Self-compassion in the Association Between Loneliness with Depressive Symptoms: A Cross-Sectional Survey Study Among Older Adults Living in Residential Care Homes During COVID-19

The coronavirus disease 2019 (COVID-19) pandemic is an ongoing geriatric health emergency with a substantial increase in the prevalence of medical and mental health issues, particularly among older adults living in residential care homes. The knowledge of the risk and protective factors related to the psychological impact of the COVID-19 pandemic on older adults living in residential care homes is based on limited data. This study aimed to investigate whether loneliness mediates the effects of fear generated by a pandemic on depression. Additionally, we hypothesized that self-compassion moderates the effect of loneliness on depression. A sample comprised 323 older adults (females: n = 141, males: n = 182) with mean age = 74.98 years (standard deviation = 6.59, age 65-90) completed a survey comprising the Fear of COVID-19 Scale, De Jung Gierveld Loneliness Scale, the nine-item Patient Health Questionnaire, and the Self-compassion Scale. The results revealed that the total effect of fear on depression was statistically significant, with a medium effect size (Cohen's f 2 = .14) and this association was partially mediated by loneliness (β = .11, SE = .04, P < .001, t = 2.91, 95% CI 0.04-0.19). The self-compassion also moderated the loneliness effect on depression. The findings of this study support COVID-19 evidence, indicating that a greater level of fear generated by the pandemic is linked to depression and loneliness. The findings support the notion that self-compassion mitigates the adverse effects of stressful events in older adults. Customized self-compassion programs may be effective loneliness-mitigating interventions for older adults living in residential care homes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11469-023-01014-0.

Can afternoon napping protect against the negative effect of short or long sleep duration on cognitive function? A prospective study

OBJECTIVES

Afternoon napping has been found to be able to compensate for the negative health effects of less optimal nighttime sleep duration. Our study aimed to investigate whether napping can protect against the negative effects of short or long sleep duration on cognitive function among middle-aged and older adults.

METHODS

A total of 8107 participants (men, 53.19%) aged 45 and older from the China Health and Retirement Longitudinal Study were followed prospectively for 7 years. The primary outcome was cognitive function (episodic memory and mental status). Afternoon napping was categorized into three groups including non- (0 min), moderate (1-30 min) and long (>30 min) duration. Nighttime sleep was also categorized into three groups including short (<7 h), normal (7-8 h), and long (>8 h) duration. Linear mixed models were used with napping and sleep duration at baseline as predictors. Potential confounders including baseline cognitive function were adjusted.

RESULTS

Shorter sleep duration (B = -0.01, p = 0.048) was independently associated with a faster decline in episodic memory. For participants with shorter sleep duration, either non-napping (B = -0.03, p = 0.017) or longer napping (B = -0.04, p = 0.018) showed a significant decline of episodic memory. For participants with longer sleep duration, non-napping was associated with a significant decline of episodic memory (B = -0.07, p = 0.003).

CONCLUSIONS

This study found that moderate napping could protect against the negative effects of short or long sleep duration on episodic memory, which implied that middle-aged and older adults who have a less optimal sleep duration might benefit from moderate napping for their cognitive function.

Examining the Combined Effects of Social Isolation and Loneliness on Memory: A Systematic Review

BACKGROUND

Some research suggests social isolation and loneliness are important risk factors for reduced successful aging and cognitive health. However, findings are inconsistent and no prior systematic review has investigated whether social isolation and loneliness are associated with the memory domain of cognition. This review examined whether social isolation and loneliness individually and jointly affected the memory of middle- and older-aged adults.

METHODS

We used PubMed, PsycInfo, and Scopus to search for comparative studies that examined the impact of both loneliness and social isolation (e.g., social activity, social networks) on memory (including all subtypes) in populations aged ≥ 45 years. Three raters performed data extraction and risk of bias assessment using the Joanna Briggs Institute checklist. Data were synthesized narratively following the Synthesis without Meta-Analysis guideline.

RESULTS

In 12 included articles, higher levels of loneliness and social isolation (combining a range of different indicators) were associated with lower memory performance, where the interaction between loneliness and social isolation had the largest adverse effect on memory, followed by social isolation alone, and followed by loneliness alone. However, substantial heterogeneity was observed in the composition of the two most common indicators of social isolation (social network size, social activity participation), with the magnitude of most results being clinically non-important. Most articles had moderate risk of bias.

CONCLUSION

This review found an inverse association between social isolation/loneliness and memory, and outlines future steps to systematically combine the two constructs and measure social isolation in a consistent, multi-modal format.

Are social isolation and loneliness associated with cognitive decline in ageing?

Objective

Social isolation and loneliness are associated with poor health (immunity, inflammation, etc.) in ageing. The purpose of this scoping review was to investigate the link between social isolation, loneliness (as distinct constructs, in contrast to previous published work) and cognition in cognitively healthy older adults.

Method

We followed PRISMA-ScR guidelines. Our search, conducted between January 2017 and April 2021, yielded 2,673 articles, of which, twelve longitudinal studies were finally identified as meeting the inclusion criteria. Multiple cognitive functions (short-term and episodic memory, attention, and global cognitive functioning) were measured.

Results

The results showed that both social isolation and loneliness were associated with poor cognition in ageing, with depression as a possible mediator between loneliness and poor cognition. Some studies also suggested that the link between social isolation, loneliness and cognitive decline may be bidirectional.

Conclusion

We conclude that both social isolation and loneliness may have a different impact on cognition. While depression may be an important mediator between loneliness and cognitive decline, the lack of cognitive stimulation may be a greater mediator between social isolation and cognitive health.

Loneliness and mood disorders: consequence, cause and/or unholy alliance?

PURPOSE OF REVIEW

People with persistent depressive disorders and with bipolar disorder are more likely to feel lonely than people in the general population. This evidence update focused on studies in the last 2 years, characterized by the COVID-19 pandemic and consequent social distancing directives.

RECENT FINDINGS

Longitudinal studies identified that people who feel lonely are more likely to become depressed or to experience relapse of mood disorders. There is emerging evidence that feelings of loneliness or mandatory social isolation can precede manic episodes. Hence the relationship between loneliness and mood disorders is complex and bidirectional. Interventions were developed to reduce loneliness in people with mental health problems, including depressive disorders, through cognitive modification and/or supported socialisation. No loneliness-focused interventions have been specifically tailored to people with bipolar disorder.

SUMMARY

Studies carried out before and during the COVID-19 pandemic found that feelings of loneliness can be both consequences and precursors of persistent depression and bipolar disorder. Mood symptoms and loneliness have a cumulative negative effect on physical and mental health outcomes. Conceptual overlaps and relations between loneliness and mood symptoms should be clarified in qualitative studies. Theory-driven intervention models should be developed and tested in methodologically robust studies.

Pexidartinib (PLX3397) through restoring hippocampal synaptic plasticity ameliorates social isolation-induced mood disorders

Social behavior is essential for the well-being and survival of individuals. However, social isolation is a serious public health issue, especially during the COVID-19 pandemic, affecting a significant number of people worldwide, and can lead to serious psychological crises. Microglia, innate immune cells in the brain, are strongly implicated in the development of psychiatry. Although many microglial inhibitors have been used to treat depression, there is no literature report on pexidartinib (PLX3397) and social isolation. Herein, we adopted PLX3397 to investigate the role of microglia in the modulation of social isolation. Our results found that social isolation during adolescence caused depressive-like, but not anxiety-like behavior in mice in adulthood, with enhanced expression of the microglial marker Iba1 in the hippocampus. In addition, treatment with PLX3397 reduced the expression of the microglial marker Iba1, decreased the mRNA expression of IL-1β, increased the mRNA expression of Arg1, elevated the protein levels of DCX and GluR1 and restored the dendritic spine branches and density, ultimately mitigating depressive-like behavior in mice. These findings suggest that inhibition of microglia in the hippocampus could ameliorate mood disorders in mice, providing a new perspective for the treatment of psychiatric disorders such as depression.

Use of Telecommunication and Diabetes-Related Technologies in Older Adults With Type 1 Diabetes During a Time of Sudden Isolation: Mixed Methods Study

BACKGROUND

The COVID-19 lockdown imposed a sudden change in lifestyle with self-isolation and a rapid shift to the use of technology to maintain clinical care and social connections.

OBJECTIVE

In this mixed methods study, we explored the impact of isolation during the lockdown on the use of technology in older adults with type 1 diabetes (T1D).

METHODS

Older adults (aged ≥65 years) with T1D using continuous glucose monitoring (CGM) participated in semistructured interviews during the COVID-19 lockdown. A multidisciplinary team coded the interviews. In addition, CGM metrics from a subgroup of participants were collected before and during the lockdown.

RESULTS

We evaluated 34 participants (mean age 71, SD 5 years). Three themes related to technology use emerged from the thematic analysis regarding the impact of isolation on (1) insulin pump and CGM use to manage diabetes, including timely access to supplies, and changing Medicare eligibility regulations; (2) technology use for social interaction; and (3) telehealth use to maintain medical care. The CGM data from a subgroup (19/34, 56%; mean age 74, SD 5 years) showed an increase in time in range (mean 57%, SD 17% vs mean 63%, SD 15%; P=.001), a decrease in hyperglycemia (>180 mg/dL; mean 41%, SD 19% vs mean 35%, SD 17%; P<.001), and no change in hypoglycemia (<70 mg/dL; median 0.7%, IQR 0%-2% vs median 1.1%, IQR 0%-4%; P=.40) during the lockdown compared to before the lockdown.

CONCLUSIONS

These findings show that our cohort of older adults successfully used technology during isolation. Participants provided the positive and negative perceptions of technology use. Clinicians can benefit from our findings by identifying barriers to technology use during times of isolation and developing strategies to overcome these barriers.

Association between frailty and cognitive function in older Chinese people: A moderated mediation of social relationships and depressive symptoms

BACKGROUND

To date, few studies have focused on examining either the direct or indirect effect of physical frailty on cognitive impairment. This study aimed to investigate the moderating effects of social relationships, including their individual components in the role of depressive symptoms as a mediator between frailty and cognitive impairment.

METHODS

This study included a total of 7525 Chinese older adults from the 2017-2018 wave of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Mediation analyses and moderated mediation effect analysis fully adjusted for all potential confounding factors were conducted.

RESULTS

Significant correlations were found between frailty, depression, social relationships, and cognitive function. Depression partially mediated the association of frailty with cognitive function [B = -0.198; 95 % confidence interval (CI): (-0.258, -0.143)]. Social relationships moderated the effect of frailty on cognitive function through both path b (depression-cognitive function) [B = 0.137; 95 % CI: (0.045, 0.230)], and path c' (frailty-cognitive function) [B = 0.870; 95 % CI: (0.562, 1.178)]. In addition, social activities and social networks moderated both the direct and indirect effect of the moderated mediation model. Social support only moderated the direct effect.

LIMITATIONS

The cross-sectional design of this study precludes any conclusion from the results as to the causality of cognitive impairment.

CONCLUSIONS

Social relationships moderated both the direct and indirect effects of depressive symptoms on the association between frailty and cognitive impairment. The findings suggest that interventions, such as paying attention to the mental health of old people and improving the quality of social relationships, may help break the link between frailty and cognitive impairment.