Social Isolation and Loneliness as Risk Factors for Grip Strength Decline Among Older Women and Men in China

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.

The mediating effect of depressive symptoms on the association between childhood friendship and physical function in middle-aged and older adults: Evidence from the China Health and Retirement Longitudinal Study (CHARLS)

BACKGROUND

This study examines the extent to which depressive symptoms mediate the link between childhood friendship (CF) and physical function among middle-aged and older adults in China.

METHODS

China Health and Retirement Longitudinal Study (CHARLS) data were used; specifically, CHARLS life history survey (conducted from June 1-December 31, 2014) and follow-up health survey (conducted from July 1-September 30, 2015) data were used. The Sobel test, Bootstrap test and multivariable logistic regression were performed to examine the mediating role of depressive symptoms (measured by the 10-item Center for Epidemiologic Studies Depression Scale) in the association between CF (measured by a standardized retrospective questionnaire) and physical function, which was measured by basic activities of daily living (BADL) disability, instrumental activities of daily living (IADL) disability, and grip strength.

RESULTS

A total of 12,170 participants aged 45 years or older were included in this cross-sectional study. After controlling for covariates, low-quality CF was associated with an increased prevalence of BADL disability (OR = 1.18; 95 % CI = 1.05-1.32), IADL disability (OR = 1.25; 95 % CI = 1.12-1.40), and low grip strength (OR = 1.21; 95 % CI = 1.09-1.34). The proportion of the mediating effect of depressive symptoms was 48 % for CF and BADL, 40 % for CF and IADL, and 11 % for CF and grip strength. Depressive symptoms and worse CF have a joint effect on BADL disability (OR = 3.30; 95 % CI = 2.82-3.85), IADL disability (OR = 3.52; 95 % CI = 3.03-4.09), and low grip strength (OR = 1.65; 95 % CI = 1.43-1.92).

LIMITATIONS

Not all potential confounding factors (such as childhood behavioural problems, genetic factors, and memory function) were measured in the analysis, and there may have been recall bias in the retrospective collection of CF data.

CONCLUSIONS

Individuals with high-quality CF were more likely to have a decreased prevalence of impaired physical function in later life. Depressive symptoms acted as a mediator associated with the development of CF.

Association between muscle strength and cardiometabolic multimorbidity risk among middle-aged and older Chinese adults: a nationwide longitudinal cohort study

BACKGROUND

Cardiometabolic multimorbidity (CM) is emerging as a global health challenge. This study investigated the potential impact of muscle strength on the risk of CM in middle-aged and older Chinese adults.

METHODS

In total, 7610 participants were identified from the China Health and Retirement Longitudinal Study (CHARLS). Muscle strength was measured by absolute, relative grip strength (normalized for body mass index) and chair-rising time which were classified into three categories according to tertiles stratified by gender. Cox proportional hazards models were adopted to evaluate the effect of muscle strength on CM.

RESULTS

During follow-up, 235(3.76%) participants from none cardiometabolic diseases (CMD), 140 (19.23%) from diabetes, 119 (21.17%) from heart disease, and 22 (30.56%) from stroke progressed to CM. In participants who had low relative grip strength, CM was more likely to occur in individuals with heart disease at baseline (HR: 1.89, 95%CIs: 1.10 to 3.23). Those with high chair-rising time had a higher risk of CM than those with low chair-rising time in the individuals with diabetes (HR: 1.85, 95%CIs:1.20 to 2.86) and with heart disease (HR: 1.67, 95%CIs:1.04 to 2.70). However, we did not observe an association between muscle strength and CM in participants without CMD or with stroke at baseline.

CONCLUSIONS

In Chinese middle-aged and older adults, low relative grip strength was associated with a higher risk of CM in individuals with heart disease, while high chair-rising time was associated with a higher risk of CM in individuals with diabetes or heart disease.

The association of social isolation and loneliness with sarcopenia among the middle-aged and elderly in China

OBJECTIVES

This study examined the relationship of social isolation and loneliness on sarcopenia among Chinese middle-aged and elderly people.

METHODS

Social isolation, loneliness, and sarcopenia were measured at baseline. Follow-up measures of new-onset sarcopenia were obtained 4 years later. Then used logistic regression to evaluate the association between social isolation, loneliness and sarcopenia.

RESULTS

In cross-sectional analysis, social isolation and loneliness are significantly associated with sarcopenia [OR = 1.88 (95% CI = 1.54-2.28)]. In longitudinal analysis, social isolation and loneliness are significantly associated with sarcopenia [OR = 1.09 (95% CI = 0.71-1.69)]. Social isolation and loneliness have a synergistic effect. Among them, individuals over 60 years old [OR = 2.01 (95% CI = 1.37-2.96)] and those without social support [OR = 2.64 (1.61-4.32), P-for interaction < 0.001] are at higher risk.

CONCLUSION

Social isolation and loneliness were significantly associated with sarcopenia, and there was a synergistic effect between social isolation and loneliness.

A Reciprocal Relationship between Formal and Informal Social Engagement and Handgrip Strength of Older Adults in South Korea

INTRODUCTION

The relationship between social engagement and handgrip strength has been underexplored. Further, no prior research examined a plausible reciprocal association between them.

METHODS

The study employed the seven waves of data (2006-2018) from the Korean Longitudinal Study of Aging (KLoSA) survey (7,927 respondents, mean age: 59 years old at wave 1 [71 years old at wave 7], women: 58%). It used ML-SEM, a cross-lagged panel model with fixed effects fitted by structural equation modeling with maximum likelihood estimation. In particular, the ML-SEM examined whether a reciprocal relationship existed between formal social engagement (number of association memberships and frequency of organizational activities)/informal social engagement (frequency of contact with familiar persons) and handgrip strength (the average of the four dynamometer measurements).

RESULTS

The empirical analyses identified a systematic reciprocal association between formal social engagement and handgrip strength. Specifically, formal social engagement was positively associated with handgrip strength over time (the number of association memberships standardized coefficient: 0.012*, the frequency of organizational activities standardized coefficient: 0.022***). Conversely, handgrip strength was positively related to the number of memberships (the handgrip strength standardized coefficient: 0.025*) and the frequency of organizational activities (the handgrip strength standardized coefficient: 0.042**).

CONCLUSION

The study thus supports the social causation proposition that formal social engagement in and through diverse associations may be positively associated with handgrip strength. It also validates the health selection argument that handgrip strength may increase the likelihood of formal social engagement.

Longitudinal associations of loneliness and social isolation with care dependence among older adults in Latin America and China: A 10/66 dementia research group population-based cohort study

OBJECTIVES

With increasing life expectancy and rapid ageing, there is an expanding number of older people who have functional declines, greater needs for care and support and who are at increased risk of insufficient social interaction. Longitudinal investigations on the interplay between loneliness, social isolation and care dependence remain limited. This study thus aimed to investigate the longitudinal reciprocal association between social isolation/loneliness and care dependence among older adults in Latin America and China.

METHODS

We analysed data from the population-based cohorts from the 10/66 Dementia Research Group (DRG) project (baseline 2003-07 and follow-up 2007-2010). The 10/66 DRG study recruited and followed up older adults aged 65 years or above in 11 catchment areas in Latin America and China. A total of 15,027 older adults from Latin America and China (mean age = 73.5, standard deviation = 6.5) were included in our analyses. Cross-lagged panel models were used to investigate potential reciprocal associations.

RESULTS

Loneliness was positively associated with care dependence at baseline (β = 0.11, p < 0.001 in Latin America; β = 0.16, p < 0.05 in China]. Social isolation consistently had a stronger positive association with care dependence across all study sites in both waves. Longitudinally, care dependence positively predicted loneliness (β = 0.10, p < 0.001) and social isolation (β = 0.05, p < 0.001) in Latin American study sites but not in China. Yet there was no statistical evidence of lagged effects of loneliness and social isolation on care dependence in all study countries.

CONCLUSIONS

Older people with care dependence are at risk of developing loneliness and social isolation. It is crucial to develop complex care models using a societal approach to address social and care needs holistically, especially for the older group with declining functional capacity. Future longitudinal research is required to explore the causal mechanisms of relationships and cultural differences, in order to inform the development of culturally appropriate care models.

Loneliness shapes disparities in healthy life expectancy: a multi-state analysis from China

OBJECTIVES

To assess the influence of loneliness on the healthy life expectancy of older adults in China and its gender disparities across different health indicators, in order to provide insights for enhancing the health status and subjective well-being of the older population.

METHOD

We conducted a cohort analysis using four waves of weighted samples (2008, 2011, 2014, and 2018) from the Chinese Longitudinal Healthy Longevity Survey, encompassing 15,507 respondents aged 65-99. Physical and subjective health were assessed through activity of daily living (ADL) and self-rated health (SRH), respectively. Utilizing loneliness status as a time-variant variable, we employed the multi-state interpolated Markov Chain to explore the associations between loneliness and age-specific life expectancy (LE), healthy life expectancy (HLE), and the proportion of healthy life expectancy in life expectancy (HLE/LE).

RESULTS

Compared to the non-lonely population, both LE and HLE were lower among lonely individuals. Regarding gender differences, the HLE/LE for females in the lonely population was consistently lower than that for males. The impact of loneliness on the health of older adults varied by measurement indicators and gender. Specifically, based on ADL results, the decline in HLE/LE was greater for females, with a decline of 53.6% for lonely females compared to 51.7% for non-lonely females between the ages of 65 and 99. For males, the decline was 51.4% for lonely males and 51.5% for non-lonely males. According to SRH, the gender difference in the decline of HLE/LE due to loneliness was less apparent. For males, the change in HLE/LE for non-lonely individuals was 3.4%, compared to 4.2% for lonely individuals, whereas for females, the change was 3.7% for non-lonely individuals and 4.4% for lonely individuals.

CONCLUSION

Loneliness exerts varied effects on health across different measurement indicators and gender demographics. Targeted health promotion interventions are imperative to mitigate these negative impacts, particularly emphasizing the enhancement of subjective well-being and physical functioning, especially among older adult females.

Factors Leading to a Decrease in Grip Strength Among the Oldest Old: A Large, Representative, Longitudinal Survey

OBJECTIVES

Grip strength is an indicator for physical performance and highly correlated with general health among older adults. To date, there is limited knowledge regarding the factors contributing to grip strength exclusively among the oldest old based on data from large representative samples and also including institutionalized individuals. Consequently, the purpose of our current study was to address this gap in knowledge.

DESIGN

A large representative, longitudinal study.

SETTING AND PARTICIPANTS

Survey on quality of life and subjective well-being of the very old in North Rhine-Westphalia (NRW80+), including individuals ≥80 years (residing in institutionalized settings and living in private households) in North Rhine-Westphalia (n = 1824, mean age was 86.7 years, 80 to 104 years).

METHODS

In accordance with other large cohort studies, isometric grip strength was measured using a dynamometer (Smedley Dynamometer, 100 kg).

RESULTS

Linear fixed effects regressions showed that decreases in grip strength were significantly associated with increases in age (β = -0.70, P < .001), decreases in social network size (β = 0.08, P < .05), and worsening self-rated health (β = 0.80, P < .01). In contrast, decreases in grip strength were not significantly associated with changes in marital status, changes in living situation, changes in the number of chronic conditions, changes in depressive symptoms, and changes in health literacy.

CONCLUSIONS AND IMPLICATIONS

It has been shown that age, social network size, and self-rated health were associated with grip strength among the oldest old longitudinally. Our current study may assist in identifying individuals at risk for low grip strength. For example, efforts to maintain social contacts may be beneficial to maintain grip strength. This is relevant because low grip strength contributes to unfavorable outcomes such as poor quality of life, functional impairment, cognitive decline, and reduced longevity.

The relationship between handgrip strength and cognitive function among older adults in China: Functional limitation plays a mediating role

BACKGROUND

The deterioration of cognitive function with age has become a major public health issue. To date, the underlying mechanisms of the association between handgrip strength and cognitive function were poorly understood. This study aimed to examine the mediating effect of functional limitation in the longitudinal relationship between handgrip strength and subsequent cognitive function.

METHODS

This research recruited 4416 participants aged 60 and above from wave 2015 and 2018 of the China Longitudinal Study of Health and Retirement (CHARLS). We conducted the linear regression model and bootstrap analyses to test the mediating role of functional limitation in the relationship between handgrip strength and cognitive function.

RESULTS

After adjusting the confounders, handgrip strength was positively associated with subsequent cognitive function (β = 0.12, P < 0.001) and was negatively associated with functional limitation (β = -0.14, P < 0.001). The mediation effect of functional limitation accounted for 23.33 % of the total effect regarding the handgrip strength with cognitive function, and the magnitude of mediation effect was a*b = 0.021 (95%CI: 0.017-0.027).

LIMITATIONS

The variable of functional limitations was self-reported. And this study did not analyse the severity and duration of handgrip strength loss and functional limitations, which may lose some information.

CONCLUSIONS

Our findings revealed that handgrip strength not only directly influenced cognitive function among older individuals but also indirectly via functional limitation over 3-year follow-up. Physical exercise targeting handgrip strength and functional limitation may be an effective approach to prevent and delay cognitive decline.

Association Between Types of Loneliness and Risks of Functional Disability in Older Men and Women: A Prospective Analysis

OBJECTIVE

To examine the association between types of loneliness (transient, incident, and chronic) and the risk of functional disability.

METHODS

Data were from the Health and Retirement Study 2006/2008-2016/2018. A total of 7,148 adults aged ≥50 was included. Functional status was measured by activities of daily living (ADL) and instrumental activities of daily living (IADL). Loneliness was assessed using the 3-item UCLA Loneliness Scale. We defined loneliness as no/transient/incident/chronic loneliness based on the pattern and duration of loneliness across 2006/2008 and 2010/2012. We applied multivariate Cox proportional hazard models with the new-onset ADL/IADL disability as outcome.

RESULTS

Overall, 69.3% respondents showed no loneliness; while 10.3%, 8.9%, and 11.5% showed transient, incident, and chronic loneliness, respectively. A total of 1,298 (18.16%) and 1,260 (17.63%) functionally normal respondents developed ADL and IADL disability during 36,294 person-years of follow-up, respectively. After adjusting for socio-demographic, behavioral, and health factors, chronic loneliness was associated with higher risks of ADL (hazard ratio [HR] = 1.37, 95% confidence interval [CI] = 1.16-1.63, p <0.001, χ2 = 3.60, degree of freedom [df] = 1) and IADL disability (HR = 1.25, 95% CI = 1.09-1.44, p = 0.002, χ2 = 3.17, df = 1) compared to no loneliness. By contrast, no significant associations between transient loneliness and ADL (HR = 1.17, 95% CI = 0.88-1.57, p = 0.273, χ2 = 1.10, df = 1) or IADL disability (HR = 1.16, 95% CI = 0.97-1.39, p = 0.112, χ2 = 1.59, df = 1) were found. Chronic loneliness was not associated with the risk of IADL disability in men (HR = 1.13, 95% CI = 0.91-1.40, p = 0.263, χ2 = 1.12, df = 1).

CONCLUSION

Chronic loneliness, rather than transient loneliness, is an independent risk factor for functional disability in middle-aged and older adults, especially for women.

The effect of internet use on depressive symptoms in middle-aged and older adults with functional disability: the mediating role of social isolation

Objective

The popularization of the internet provides the possibility to improve the depressive symptoms (DS) and social isolation of middle-aged and older adults with functional disability. There was a significant correlation between internet use and DS in middle-aged and older adults with functional disability, but the relationship between internet use, social isolation, and DS remains to be confirmed.

Methods

Data were obtained from 7,955 middle-aged and older adults aged 45 years and older from the 2018 China Health and Retirement Longitudinal Study (CHARLS). Multiple linear regression models were used to analyze the association between internet use and DS, and the Sobel test was used to explore mediating models.

Results

Results showed that internet use was negatively associated with DS among Chinese middle-aged and older adults. Among them, social needs (B = -0.770, p = 0.041), and information reception (B = -1.067, p = 0.007) were significantly related to DS in middle-aged and older adults. Only information reception (B = -3.161, p = 0.031) was significantly related to DS among middle-aged and older adults with functional disability. Social isolation partially mediated the association between internet use and DS in middle-aged and older adults without functional disability, whereas it was fully mediated in middle-aged and older adults with functional disability.

Conclusion

This study indicates that when formulating health policies to promote the mental health of Chinese middle-aged and older adults, the use of the internet should not be overlooked.

Ageing accounts for much of the association between decreasing grip strength and subsequent loneliness: the English Longitudinal Study of Ageing

BACKGROUND

Loneliness at older ages has been associated with higher morbidity and mortality. One of the risk factors for loneliness may be age-related decline in skeletal muscle strength, which may limit the possibilities for engagement in usual social activities and maintaining relationships. We aimed to identify if decrease in grip strength is an independent determinant of subsequent change in loneliness.

METHODS

Prospective cohort study of participants aged 50 years or older living in private households and provided data in the English Longitudinal Study of Ageing waves 2 (2004/2005), 4 (2008/2009) and 6 (2012/2013) (n=6118). We used fixed effects linear models to estimate β coefficients and 95% confidence intervals.

RESULTS

The adjusted estimates for a 5-kilogramme decrease in grip strength and loneliness score (ranging from 3 to 9) are β 0.04 and 95% CI -0.003 to 0.08 among men and β 0.03 and 95% CI -0.02 to 0.09 among women. In age-stratified analysis, a statistically significant association was observed among men below the age of 80 years (0.04, 0.0001 to 0.08) but not among older men (0.04, -0.28 to 0.35), and among women below the age of 80 years (0.03, -0.002 to 0.09) or above (-0.02, -0.32 to 0.28).

CONCLUSION

Muscle strength declines with age and may help explain the greater social isolation that occurs at older ages. Decline in strength was only independently associated with modestly increased loneliness among men younger than 80 years of age, indicating its limitation as a potential marker of loneliness risk.

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.

Cumulative loneliness and subsequent memory function and rate of decline among adults aged ≥50 in the United States, 1996 to 2016

INTRODUCTION

The study objective was to investigate the association between loneliness duration and memory function over a 20-year period.

METHODS

Data were from 9032 adults aged ≥50 in the Health and Retirement Study. Loneliness status (yes vs. no) was assessed biennially from 1996 to 2004 and its duration was categorized as never, 1 time point, 2 time points, and ≥3 time points. Episodic memory was assessed from 2004 to 2016 as a composite of immediate and delayed recall trials combined with proxy-reported memory. Mixed-effects linear regression models were fitted.

RESULTS

A longer duration of loneliness was associated with lower memory scores (P < 0.001) and a faster rate of decline (P < 0.001). The association was stronger among adults aged ≥65 than those aged <65 (three-way interaction P = 0.013) and was stronger among women than men (three-way interaction P = 0.002).

DISCUSSION

Cumulative loneliness may be a salient risk factor for accelerated memory aging, especially among women aged ≥65.

HIGHLIGHT

A longer duration of loneliness was associated with accelerated memory aging. The association was stronger among women than men and among older adults than the younger. Reducing loneliness in mid- to late life may help maintain memory function.

Social Relationships and Onset of Functional Limitation among Older Adults with Chronic Conditions: Does gender matter?

Objectives

This study aimed to examine the longitudinal association between social relationships and physical functioning among community-dwelling older adults with chronic conditions.

Methods

Self-reported questionnaires were distributed and collected between 2014 and 2017 from participants ≥65 years old. The Index of Social Interaction was used to evaluate social relationships and the instrumental activities of daily living (IADL) subscale of the Tokyo Metropolitan Institute of Gerontology Index of Competence was used to examine functional status.

Results

A total of 422 participants (190 males and 232 females) were included in the final analysis. High social relationships demonstrated significant adverse effects (odds ratio [OR] = 0.77, 95% confidence interval [CI]: 0.64-0.93) on the decline of IADL in the overall sample, particularly for females (OR = 0.71, 95% CI: 0.55-0.93) but not as much for males (P = 0.131).

Conclusion

This finding suggests that functional limitation was influenced by social relationships among disabled older adults and the influence of social relationships on functional limitation differed based on gender.

Dual Sensory Impairment as a Predictor of Loneliness and Isolation in Older Adults: National Cohort Study

BACKGROUND

Loneliness and social isolation are global public health challenges. Sensory impairments (SIs) are highly prevalent among older adults but are often ignored as a part of normal aging. Identifying the role of SIs in loneliness and social isolation could provide insight into strategies for improving public health among older adults.

OBJECTIVE

This study aims to analyze the effects of SIs on loneliness and social isolation among older adults in rural and urban China.

METHODS

This cohort study of 3069 older adults (aged 60+) used data from 4 waves (2011, 2013, 2015, and 2018) of the China Health and Retirement Longitudinal Study (CHARLS), a nationally representative survey of adults aged 45 years or older. SIs include hearing impairment (HI), vision impairment (VI), and dual sensory impairment (DSI). DSI is defined as the co-occurrence of VI and HI. Participants with complete data on hearing, vision, social isolation, and loneliness were included in the analysis. Generalized estimating equation models adjusted for covariates were used to examine the relationships of DSI with loneliness and social isolation among older adults.

RESULTS

Older adults in rural areas have higher prevalence of DSI, loneliness, and social isolation than their urban counterparts. In rural areas, participants with VI only (odds ratio [OR] 1.34, 95% CI 1.12-1.62; P=.002), HI only (OR 1.32, 95% CI 1.02-1.71; P=.03), and DSI (OR 1.84, 95% CI 1.56-2.18; P<.001) were more likely to experience loneliness compared with participants without SIs. DSI showed a statistically significant association with loneliness compared with VI only (OR 1.37, 95% CI 1.22-1.54; P<.001) and HI only (OR 1.39, 95% CI 1.13-1.72; P=.002). In urban areas, participants with VI only (OR 2.44, 95% CI 1.57-3.80; P<.001), HI only (OR 2.47, 95% CI 1.41-4.32; P=.002), and DSI (OR 1.88, 95% CI 1.24-2.85; P=.003) were more likely to experience loneliness compared with participants without SIs. DSI was not associated with the increased likelihood of loneliness compared with HI only or VI only. SIs were not associated with social isolation among older adults in urban and rural areas. Until 2018, 86.97% (2669/3069) reported VI, but only 27.11% (832/3069) and 9.45% (290/3069) were treated with glasses and cataract surgery, respectively; besides, 75 individuals received both glasses and cataract surgery treatment. The prevalence of HI was 74.39% (2283/3069) in 2018, but only 0.72% (22/3069) were treated with a hearing aid.

CONCLUSIONS

SIs are associated with an increased risk of loneliness rather than social isolation. A compounded risk of DSI on loneliness exists in rural areas rather than in urban areas. These findings expand our knowledge about the effects of SIs on loneliness and social isolation in non-Western populations. Interventions targeting HI only and DSI might be particularly effective for mitigating loneliness of older adults in urban and rural areas, respectively. Considering the high prevalence and low treatment rate of SIs, measures should be taken to make treatment more accessible.

Loneliness and physical function impairment: Perceived health status as an effect modifier in community-dwelling older adults in Ghana

Background

Methods

Results

Conclusions

The Association between Social Participation and Loneliness of the Chinese Older Adults over Time-The Mediating Effect of Social Support

Based on activity theory, this paper employed data from the 2013, 2015, and 2018 waves of the China Health and Retirement Longitudinal Survey, and adopted Hierarchical Linear Modeling and longitudinal mediation analysis to explore the temporal variation characteristics of loneliness and the influence of social participation on loneliness in Chinese Older Adults, as well as the mechanism of them. The study found that loneliness among older adults overall was at a moderate level from 2013 to 2018 and increased over time, which may be related to decreasing social participation from year to year. Decreased social participation was associated with increased loneliness over time (β = -0.060, p < 0.001) and lower social support (β = 0.109, p < 0.001), which was associated with more loneliness (β = -0.098, p < 0.001). In addition, social support played a significant mediating role in the realization of social participation in alleviating loneliness. Social participation can not only directly reduce loneliness, but also reduce loneliness by increasing social support.

The Influence of Interpersonal Behaviors and Population Density on Grip Strength of Elderly People: An Analysis of the Direct vs. Indirect Effects via Social Participation

The impact of social participation (SP) on the health of the elderly has been widely recognized, and urban-rural differences in social participation have attracted attention. However, few studies discussed the impact of social participation on specific health indicators and the further subdivision of urban-rural differences. This research aims to use the dimensions of interpersonal behaviors and population density rather than simple urban-rural distinctions to justify community differences and compare these differences' direct and indirect effects on grip strength. This study used 15,871 respondents aged over 50 years from the China Health and Retirement Longitudinal Study (CHARLS). An SEM (Structural Equation Modeling) analysis was used to explore the joint effect of interpersonal behavior and population density on social participation and the consequent impact on changes in grip strength and compare the differences among different genders, ages, wealth levels, and family relationships. The results indicated that community differences characterized by interpersonal behavior and population density have direct effects on grip strength and indirect effects on it through social participation. The conclusion is that the frequency of social activities, such as mah-jong and dancing in the Metropolitan Fringe and county-level cities is higher than that in Metropolitan centers. The high frequency of these activities has a positive and indirect impact on grip strength, and community differences have a more significant impact on women's social participation than men. However, the direct effect of community differences as defined by interpersonal communication and population density on grip strength is greater than the indirect effect of other factors through social participation.

Social Isolation Is Associated With Rapid Kidney Function Decline and the Development of Chronic Kidney Diseases in Middle-Aged and Elderly Adults: Findings From the China Health and Retirement Longitudinal Study (CHARLS)

Background: There is limited evidence on the relationship between social isolation and renal outcomes. To address this gap, this study estimated the prospective relationship of social isolation with rapid kidney function decline and the development of chronic kidney disease (CKD) in middle-aged and elderly Chinese with normal kidney function. Methods: We analyzed data from 3,031 participants aged ≥ 45 years with baseline estimated glomerular filtration rates (eGFR) ≥ 60 ml/min/1.73 m². All data were obtained from the 2011 and 2015 waves of the Chinese Longitudinal Study of Health and Retirement (CHARLS). eGFR was estimated based on a combination of serum creatinine and cystatin C. The primary outcome was rapid decline in renal function, as defined by an eGFR decrease of > 5 ml/min/1.73 m² per year, while the secondary outcome was the development of CKD, as defined by an eGFR decrease to a level < 60 ml/min/1.73 m². Results: During the follow-up of 4 years, 258 (8.5%) participants experienced a rapid decline in renal function, while 87 (2.9%) developed CKD. In the fully adjusted model, high social isolation was significantly related to an increased risk of experiencing a rapid decline in renal function (OR 1.805, 95% CI 1.310-2.487) and CKD onset (OR 1.842, 95% CI 1.084-3.129). Among the five components of social isolation, being unmarried, not participating in social activities, and living alone independently predicted declined renal function. Conclusions: Social isolation is significantly associated with the risk of rapid eGFR decline and CKD onset in middle-aged and older adults with normal kidney function in China.

Own health, spousal health and transitions in loneliness among middle-aged and older adults in China

This study examines the effects of own and spousal health on transitions in loneliness over time among married middle-aged and older adults in China, and explores the possible gender differences in these effects using data from the three waves of the China Health and Retirement Longitudinal Study (2011–2015). The sample includes 6,422 men and 6,391 women who were married and aged 45 and older at the baseline survey. Middle-aged and older adults with poorer physical and emotional health statuses are more likely to transition into and less likely to transition out of loneliness in a two-year period. Spouse's emotional health also affects both types of transition in loneliness and spouse's functional limitation affects transition into loneliness through spouse's emotional health. In addition, for married men, their own functional limitation is significantly associated with their transitions into and out of loneliness. For married women, their spouse's functional limitation is significantly associated with their transition into loneliness and this is mainly through its association with spouse's emotional health. Also, for married women, their spouse's emotional health is significantly associated with their transition out of loneliness. Social interventions to reduce feelings of loneliness need to take a couple approach and consider both spouses’ health problems and how they may affect their daily activities and their interactions with each other and with others.

Impact of Social Isolation on Physical Functioning Among Older Adults: A 9-Year Longitudinal Study of a U.S.-Representative Sample

INTRODUCTION

Social isolation among older adults is associated with poor health and premature mortality, but its impact on physical functioning is not fully understood. Previous studies have typically relied on community samples, cross-sectional data, and suboptimal prospective designs. This study generates more robust evidence by investigating the longitudinal associations between social isolation and physical functioning in a large panel of older adults.

METHODS

Analyses were based on 9 waves of data (2011-2019) from a sample of adults aged ≥65 years from the U.S. National Health and Aging Trends Study (N=12,427 individuals; 54,860 person-year observations) and within-individual fixed-effect panel regression models. Analyses were conducted in 2020. Social isolation was measured using the Social Isolation Index, and physical functioning was measured through the Short Physical Performance Battery.

RESULTS

In fully adjusted fixed-effect regression models, each 1-unit increase in the Social Isolation Index resulted in an average decrease of 0.27 units in the Short Physical Performance Battery (95% CI= -0.31, -0.24). This relationship was moderated by age, with the Social Isolation Index bearing a significantly and substantially stronger influence on the Short Physical Performance Battery at older ages than at younger ages.

CONCLUSIONS

This study confirms that social isolation is associated with deficits in physical functioning among older adults in the U.S. using more robust data and methods than earlier studies. These findings highlight the importance of incorporating strategies to reduce social isolation in policies aimed at promoting successful aging.

Association Between Muscle Strength and Cystatin C-Based Estimated Glomerular Filtration Rate Among Middle-Aged and Elderly Population: Findings Based on the China Health and Retirement Longitudinal Study (CHARLS), 2015

Background

Patients with chronic kidney disease (CKD) are prone to muscle strength degeneration. However, the relationship between mild-to-moderate renal insufficiency and low muscle strength remains unclear. As cystatin C is not subject to muscular conditions and is a sensitive serum marker in preclinical renal disease, we aimed to investigate the association between estimated glomerular filtration rate (eGFR) based on cystatin C and muscle strength in the Chinese population.

Methods

This was a cross-sectional study enrolling 12,398 Chinese participants aged above 45 years (5762 men and 6636 women) from the 2015 China Health and Retirement Longitudinal Study. Handgrip strength (HGS) was used to assess muscle strength. Locally weighted scatterplot smoothing (LOWESS) curves were employed to visualize the relationships between eGFR and HGS. Multivariable logistic regression was conducted to analyze the correlation between kidney function and low muscle strength.

Results

Significant differences in HGS by CKD stage were observed in both sexes after adjusting for age and body mass index. LOWESS curves demonstrated concomitant decreases in HGS and kidney function at eGFR levels below 120 mL/min/1.73 m² in both sexes. According to multivariate logistic regression, participants with CKD stages 2 (odds ratio [OR]: 1.256, 95% confidence interval [CI]: 1.120–1.409), 3 (OR: 2.725, 95% CI: 2.2585–3.288), and 4–5 (OR: 3.069, 95% CI 1.747–5.392) had higher risk of low muscle strength than those who were normal or had CKD stage 1 after adjusting for demographic and clinical variables.

Conclusion

Our study illustrated that CKD stage was independently associated with low muscle strength in Chinese middle-aged and elderly populations.

Social isolation and cognitive decline among older adults with depressive symptoms: prospective findings from the China Health and Retirement Longitudinal Study

OBJECTIVES

Identifying potentially modifiable risk factors of cognitive decline among people with depressive symptoms could provide insight into strategies for improving treatment effect of depression and prevention of dementia. Quite a few studies have examined the association between social isolation and cognitive function directly among depressed older adults and the results are still mixed. The aim is to examine the association of social isolation and cognitive decline among older adults with depressive symptoms in a non-Western country.

METHODS

This study used data from the China Health and Retirement Longitudinal Study (CHARLS). Depressive symptoms were measured by the Chinese version of the 10-item Center for Epidemiological Studies Depression Scale (CESD-10) (elevated depressive symptom cutoff≥10). Social isolation was assessed based on responses to four items: marital status, residence, contact with children, and social activity. Lagged dependent variable regressions adjusted for confounding factors were used to evaluate the association between baseline social isolation and follow-up cognitive function.

RESULTS

A number of 2,507 participants [mean age (SD)=61.37 (7.26); male, 41.0%] with increased depressive symptoms were available for the present study. Baseline social isolation was significantly associated with 4-year episodic memory (β=-0.08, p<0.001) in depressed women, but not men (β=-0.03, p=0.350). No significant association between baseline social isolation and follow-up mental status was found for women (β=-0.04, p=0.097) or men (β=0.01, p=0.741).

DISCUSSION

This longitudinal study found that social isolation was significantly associated with memory decline over 4 years among depressed women (but not men) in China.