The effects of loneliness, social isolation, and associated gender differences on the risk of developing cognitive impairment for Chinese oldest old

Association between loneliness and mild cognitive impairment in older adults: a meta-analysis of longitudinal studies

OBJECTIVES

Prior studies reporting the effects of loneliness on mild impairment cognitive (MCI) have generated inconsistent results. This meta-analysis aimed to investigate the longitudinal association between loneliness and risk of MCI among community-dwelling middle-aged and older adults.

METHOD

Five electronic databases were searched from inception to 9 May 2023. Eligible studies examined the longitudinal association between loneliness and cognitive outcomes, including incident MCI, cognitive impairment, and cognitive decline. Odds ratios (OR) and 95% confidence intervals (CIs) were calculated using random-effects or fixed-effects meta-analysis. Sensitivity analysis and subgroup analysis were conducted. Publication bias was examined using Egger's and Begg tests.

RESULTS

Eight studies were included. Among the 45,032 participants, 10,570 were diagnosed with MCI/cognitive decline. Loneliness was positively associated with an increased risk of MCI (overall OR = 1.14; 95% CI = 1.05, 1.23), with moderate heterogeneity (I2 = 44.2%). Sensitivity analysis have minimal influence on the aforementioned pooled effect. Subgroup analyses indicated stronger associations in studies which employed incident MCI as cognitive outcome (OR = 2.55, 95%CI = 1.31, 1.83), were conducted in non-Asia countries (OR = 1.52, 95%CI = 0.95, 1.20), and reported no depression adjustment (OR = 1.51, 95%CI = 1.04, 1.25). The association between loneliness and MCI was stronger among males compare to females. The Egger test and Begg test showed no evidence of significant publication bias (p = .493; p = .474).

CONCLUSION

The findings indicated that loneliness was associated with an increased risk of MCI. Future longitudinal studies should evaluate potential cases of MCI through comprehensive clinical assessments by practitioners to draw robust findings on the association of loneliness with MCI.

The association between perceived social functioning and heart rate variability is mediated by subclinical depressive symptomatology and moderated by gender

Chronic loneliness and low perceived social support have been recognized as risk factors for both mental and cardiovascular disorders. It has been proposed that their link to psychophysiological problems may involve changes in parasympathetic activity. However, the exact underlying psychopathological mechanisms and the moderating effects of gender are still not thoroughly examined. Thus, the present study investigated associations between perceived social functioning and resting vagal tone in the context of potential cognitive and subclinical mediators and gender differences. Three hundred twenty-five young adults (aged 18-35, 180 women) underwent an electrocardiogram measurement of 6-minute resting heart rate variability (HRV). They also completed questionnaires assessing loneliness, perceived social support, social cognitive biases, depressive and social anxiety symptoms, and general mental health. In men, HRV was significantly and negatively associated with poorer perceived social functioning, depressive symptoms, and self-reported social cognitive biases, while in women, there was a quadratic link between HRV and depressive symptoms and HRV and general mental health. Moderated mediation analysis revealed that depressive symptoms fully mediated the relationship between perceived social functioning and HRV in men. The results suggest that decreased resting vagal tone in lonely individuals is linked to depressive symptomatology rather than to specific social cognitive biases and that this association is significant only in men.

Exploring the associations between structural and functional aspects of social relationships and cognition in very old age

OBJECTIVES

Few studies have examined the associations between social relationships and cognition in very old adults (80+ years). Moreover, limited research has considered structural and functional aspects of social relationships together when exploring their associations with cognition. Therefore, the present study aimed to investigate the associations between structural and functional social aspects and cognition in very old age.

METHOD

The sample comprised 518 two-wave participants of the NRW80+ Study, who showed no indication of dementia and an average age of 85 years at baseline (range: 80-97 years). They were assessed twice over an approximate 2-year interval. Multilevel linear growth curve analysis was employed to model cognitive development over very old age and to examine the associations between structural and functional aspects of social relationships and cognitive development. It was controlled for demographic and health characteristics.

RESULTS

A larger social network size (ß = 0.05, 95% CI [0.02, 0.08], p = 0.002) and frequent compared with occasional, seldom, and no contact with others (ß = 0.16, 95% CI [0.03, 0.28], p = 0.013) were associated with higher global cognition in the fully-controlled model. Model comparisons further revealed that structural aspects better predicted global cognition in very old age compared to functional aspects (χ2(2) = 16.17, p < 0.001).

CONCLUSION

The findings underline the positive association between structural aspects of social relationships and global cognition in very old age. They also highlight the need for interventions promoting a socially active lifestyle to prevent cognitive decline in this vulnerable age group.

Bidirectional and Dynamic Relationships Between Social Isolation and Loneliness Among Older Adults in China

OBJECTIVES

This study aimed to investigate the bidirectional associations and temporal dynamics between social isolation (SI) and loneliness among older adults.

DESIGN

This is a prospective cohort study.

SETTING AND PARTICIPANTS

With the global phenomenon of population aging, there has been a significant increase in the prevalence of SI and loneliness among older adults. These factors exert substantial impacts on the health and well-being of this population. Consequently, it is imperative to implement more effective interventions targeting SI and combating loneliness in order to enhance the overall health and well-being of older adults.

METHODS

Data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) were analyzed, focusing on individuals aged 65 and older. Generalized Cross-Lagged Modeling (GCLM) was used to assess these associations.

RESULTS

The findings reveal significant cross-lagged effects between SI and loneliness over the course of 16 years. Higher levels of SI at 1 time point predict increased loneliness scores in subsequent periods, and greater levels of loneliness at 1 time point predict higher SI scores in future periods. Notably, the impact of SI on loneliness is found to be larger and more enduring compared to the influence of loneliness on SI. These cross-lagged effects persist over an extended period, indicating a long-term reciprocal relationship between SI and loneliness among older adults.

CONCLUSIONS AND IMPLICATIONS

This study provides valuable insights into the bidirectional associations between SI and loneliness among older adults. Given that the effect of SI dominates, the findings suggest that public health strategies aimed at promoting health and well-being should prioritize interventions that enrich older adults' social networks. Emphasizing early interventions aimed at enhancing social networks is essential for promoting healthy aging and overall well-being.

Bidirectional and dynamic relationships between social isolation and activities of daily living among older adults in China

Background

Social isolation and disability in performing activities of daily living are increasingly recognised as significant public health concerns globally. We aimed to investigate their bidirectional associations and the related temporal dynamics in Chinese older adults.

Methods

We retrieved data from the six waves of the Chinese Longitudinal Healthy Longevity Survey (2002-18) and used generalised cross-lagged modelling (GCLM) to assess the bidirectional associations between social isolation and disability in performing activities of daily living.

Results

We found that higher levels of social isolation were predictive of increased scores in disabilities in performing activities of daily living. Conversely, disabilities in performing activities of daily living showed less predictive power in relation to social isolation. The temporal dynamics analysis indicated a peak in the bidirectional associations after approximately six years, followed by decreasing trends.

Conclusions

Our results indicate that social isolation is dominant in the bidirectional relationship. Efforts focusing on reducing it can potentially minimise disabilities in performing activities of daily living among older adults. Reinstating preventive interventions beyond the six-year mark could help maintain their effectiveness.

Hearing Impairment and Cognitive Function: Mediating Role of Social Isolation and Depression

ObjectivesTo examine the relationship between hearing impairment and cognitive function and the mediating role of social isolation and depression. Methods: Data came from the 2018 China Health and Retirement Longitudinal Study wave. A self-reported item, a composite index, the 10-item Center for Epidemiological Studies Depression Scale, and the Mini-Mental State Exam were used to measure hearing impairment, social isolation, depression, and cognitive function, respectively. Mediation analysis was performed. Results: 6799 participants were included. For participants reporting mild hearing impairment and severe hearing impairment, there were significant direct and indirect effects on cognitive function. Social isolation mediated 2.75% and 6.33% of the relationship between mild hearing impairment, severe hearing impairment, and cognitive function, respectively. The direct effect of hearing impairment outweighed the mediation effect of social isolation on cognitive function. Conclusions: Decreased cognitive function linked to hearing impairment might benefit from addressing hearing impairment and social isolation in older adults.

Patterns of Social Isolation and Low Social Support and Frailty Trajectories Among Chinese Older Adults

Objectives: This study aims to identify patterns of social isolation and low social support, and discover their associations with frailty trajectories among Chinese older adults. Methods: The paper used five waves of the Chinese Longitudinal Healthy Longevity Survey (CLHLS, 2005-2018). The latent class analysis, multi-trajectory modeling, and the multinomial logistic regression approaches were used to perform the analysis. Results: The paper identified five types of social isolation and low social support, and three typical frailty trajectories. Patterns of social isolation and low social support were associated with frailty trajectories among older adults. Conclusions: Distinct patterns of social isolation and low social support were significantly correlated with frailty trajectories. To improve frailty trajectories among older adults, interventions such as Healthy China 2030 should prioritize addressing the interplay between social isolation and low social support.

Association between sensation, perception, negative socio-psychological factors and cognitive impairment

Background

Evidence has suggested that sensation and socio-psychological factors may be associated with cognitive impairment separately in older adults. However, the association between those risk factors and cognitive impairment is still unknown.

Objective

To investigate the association between sensation, perception, negative socio-psychological factors, and cognitive impairment in institutionalized older adults.

Methods

From two public aged care facilities, 215 participants were investigated. The Mini-mental State Examination was applied to assess cognitive function. The sensory function was bifurcated into auditory and somatosensory realms which were evaluated using pure tone audiometry and Nottingham Sensory Assessment, respectively. Albert's test, left and right resolution, and visuospatial distribution were used to evaluate perception. Depression and social isolation were selected as negative socio-psychological factors and were evaluated by the Geriatric Depression Scale and the Lubben Social Network Scale. The multivariate analysis was performed utilizing binary logistic regression.

Results

Participants with moderately severe or severe hearing loss exhibited significant cognitive impairment compared to those with mild hearing loss. It was observed that perceptual dysfunction and depression were independently related to cognitive impairment. However, there was no significant association between somatosensory function, social isolation, and cognitive impairment in the institutionalized older adults.

Conclusion

More profound hearing loss, abnormal perception, and depression are associated with cognitive impairment in older adults. Subsequent research endeavors should delve into the causal mechanisms underpinning these associations and explore whether combined interventions have the potential to postpone the onset of cognitive impairment.

Unmet needs and depression among spousal caregivers: the mediating role of marital satisfaction

OBJECTIVES

Previous research has identified that unmet needs are associated with adverse mental health outcomes in older adults. However, the unmet needs of older adults' spousal caregivers are unknown. The present study examined the association between unmet needs and depression among spousal caregivers, and whether marital satisfaction mediated this association.

METHODS

We included 1,856 participants who provided care to their spouses with difficulties in activities of daily living (ADL) and instrumental activities of daily living (IADL) from the 2018 China Health and Retirement Longitudinal Survey. Unmet needs of spousal caregivers were assessed as the total number of ADL/IADL tasks with which respondents had unmet needs. Path models were conducted to evaluate the associations between unmet needs, marital satisfaction, and depression. Subgroup analyses by sex were conducted to examine the sex differences regarding the associations.

RESULTS

Spousal caregivers with more unmet ADL/IADL needs reported higher levels of depression (p < 0.001). Additionally, for wife caregivers, unmet ADL/IADL needs were associated with lower marital satisfaction, and lower marital satisfaction was associated with higher degrees of depression, indicating that marital satisfaction partially mediated the association between unmet needs and depression (p < 0.01). However, marital satisfaction did not mediate the association between unmet needs and depression among husband caregivers.

CONCLUSIONS

The mediating effect of marital satisfaction on the association between unmet needs and depression only existed in wife caregivers. Social services should be provided to meet the needs of caregivers with ADL/IADL difficulties, and interventions should be implemented to promote the marital satisfaction of wife caregivers.

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.