Negative wealth shocks and subsequent depressive symptoms and trajectories in middle-aged and older adults in the USA, England, China, and Mexico: a population-based, multinational, and longitudinal study.

BACKGROUND: The association between negative wealth shocks and depression among middle-aged and older individuals remains unclear. Our study aimed to assess the association between negative wealth shocks and depression and its trajectories, and to explore cross-national differences in these associations. METHODS: Our sample included 21 999 participants, of which 9519 were from the Health and Retirement Study (2012-2020), 4936 from the English Longitudinal Study of Ageing (2012-2020), 2520 from the China Health and Retirement Longitudinal Study (2011-2020), and 5024 from the Mexican Health and Aging Study (2012-2021). We used latent class trajectory models to identify depressive trajectories, alongside mixed-model logistic regression and multinomial logistic regression to evaluate associations. RESULTS: In the USA (OR 1.73, 95% CI 1.40-2.16), England (OR 1.71, 95% CI 1.09-2.70), and China (OR 1.38, 95% CI 1.09-1.75), negative wealth shocks were associated with subsequent depressive symptoms, but not in Mexico (OR 1.06, 95% CI 0.86-1.29). Additionally, negative wealth shocks were associated with several depressive trajectories in the USA and China. This association occurred only in increasing-decreasing trajectory in England, while no significant association was found across any trajectory in Mexico. CONCLUSIONS: Negative wealth shocks were associated with subsequent depressive symptoms, with significant associations observed in some specific depressive trajectories. These associations exhibited cross-national differences, underscoring the importance of considering country-specific contexts when addressing the mental health impacts of wealth shocks.

Weight-adjusted waist index and disability: a cohort study from CHARLS.

BACKGROUND: The association between weight-adjusted waist index (WWI) and disability is unclear. This study aimed to assess the relationship between WWI and disability in middle-aged and elderly Chinese individuals and provide more predictive indicators for disability prevention. METHODS: In this study, 13,015 middle-aged and older adults aged 45 years and above who were surveyed in 2011 by the China Health and Aging Tracking Survey (CHARLS) database were selected, and 8344 respondents with complete data were included for cohort analysis after seven years of follow-up. Information on clinical demographic characteristics, anthropometric indices, assessment of disability, and related covariates were collected, and the presence or absence of disability was assessed by the disability scale. WWI was calculated by dividing the waist circumference (cm) by the square root of the body weight (kg). Cox proportional hazards model was used to analyze the association between WWI and disability after follow-up. RESULTS: Our study found that 2912 of 8344 participants had disability after seven years of follow-up, and disability incidence was approximately 34.9%. Age, sex, place of residence, chronic disease, depression, waist circumference, and WWI were significantly associated with disability in univariate analysis. Among them, there was a positive association between WWI as a continuous variable and incidence of disability (hazard ratio (HR) = 1.26, 95% CI: 1.22-1.31, p < 0.001). WWI was transformed into categorical variables using quartiles as cutoffs for disability regression analysis. After adjusting covariates, HR values in the 2nd, 3rd and 4th quantile showed an increasing trend compared with the 1st quantile, and the risk of disability among WWI subjects in the 4th quantile increased by 43% (95% CI: 1.24-1.64). P values for the trend test in the model were all < 0.001. In subgroup analyses, the positive association between WWI and risk of disability remained robust for sex, age, alcohol consumption, smoking status, education level, marital status, and place of residence after adjusting for all covariates considered in this study. CONCLUSIONS: WWI is a new and reliable obesity-related indicator that can be used for disability prevention. WWI can be detected and controlled for reducing the risk of disability.

The impact of long-term care insurance on healthcare utilization and expenditures among middle-aged and older Chinese adults: a quasi-experiment study.

BACKGROUND: Long-term care insurance (LTCI) is essential to alleviate the challenges of rapid aging. Research on LTCI in developing countries is limited and conclusions remain controversial. This study aims to empirically evaluate how the LTCI pilot in selected cities influences healthcare utilization and expenditures among middle-aged and older Chinese adults. METHODS: Data was from 2013, 2015, and 2018 China Health and Retirement Longitudinal Study. 167 LTCI and 8225 non-LTCI group participants were identified. Propensity score matching difference-in-difference method was used to evaluate the net effect of LTCI. The robustness of the findings was tested using a placebo test. RESULTS: In the pilot cities, around 17.8% of the population had LTCI coverage, with approximately 59.9% participating in urban employee medical insurance and 81.4% being urban residents. LTCI significantly reduced the monthly out-of-pocket outpatient expenditure by 313.764 yuan (P < 0.05), but had no significant effects on the inpatient utilization and expenditure. Further analysis of vulnerable subgroup revealed that LTCI decreased monthly outpatient visits frequency, total outpatient expenditure, and out-of-pocket outpatient expenditure by 0.523 times, 643.500 yuan, and 302.367 yuan, respectively (P < 0.05). Robustness tests confirmed the stability of these results. CONCLUSIONS: The LTCI coverage rate has remained low. While LTCI has contributed to reducing outpatient utilization and expenditure, its impact on controlling inpatient-related outcomes is limited. It is recommended to broaden LTCI coverage beyond existing participants to encompass more vulnerable populations, and improve awareness and quality of LTCI services to achieve a significant effect on inpatient care.

Medical service satisfaction and depression among middle-aged and older Chinese adults: moderating role of distinct Internet-using patterns.

BACKGROUND: Patient satisfaction is a powerful predictor of an individual's mental health, according to previous research. However, there has not been a thorough study on the relationship between depression and overall medical service satisfaction (OMSS) in middle-aged and older adults. Moreover, little is known about how different Internet-using patterns affect this relationship. METHODS: We selected 4,523 participants from the China Family Panel Studies (CFPS) 2020 dataset who were aged 45 and older. The relationship between OMSS and depression was examined using logistic regression analysis, distinct Internet-using patterns were investigated using latent class analysis, and the moderating effects of these patterns were examined using SPSS PROCESS macro analysis. RESULTS: The results showed OMSS was negatively related to depression in middle-aged and older adults (ß = -0.181, p < 0.001). For skilled Internet users, there was a significant positive moderating effect (ß = -0.272, SE = 0.096, p < 0.01), for unskilled users, there was a significant negative moderating effect (ß = 0.497, SE = 0.156, p < 0.01). Yet, there is no moderating effect of a controlled Internet-using pattern on the correlation between OMSS and depression. CONCLUSIONS: This study highlights the potential value of improving medical service satisfaction in reducing depressive symptoms in middle-aged and older adults. Additionally, in order to maximize the benefits of healthcare for mental health, the study suggests that Internet-using patterns could be a significant area for intervention.

Association of internet use and health service utilization with self-rated health in middle-aged and older adults: findings from a nationally representative longitudinal survey.

Objective: This study aims to explore the relationship between internet use and self-rated health among middle-aged and older adults and further investigates the mediating role of health service utilization between internet use and self-rated health, providing a reference for more effectively utilizing the internet to improve the health status of middle-aged and older adults. Method: We analyzed data from the 2018 and 2020 waves of the China Health and Retirement Longitudinal Study (CHARLS), this includes 10,011 in 2018 and 7,080 in 2020 over the age of 45. To explore the relationship between internet use and self-rated health, we employed propensity score matching (PSM) and instrumental variable regression analysis, accounting for a wide range of potential covariates. Additionally, the Sobel test was used to examine the mediating effect of health service utilization on this relationship. Results: According to the fully adjusted propensity score matching and instrumental variable regression model, internet use significantly enhanced self-rated health among middle-aged and older adults (ß = 0.348, P < 0.01; ß = 0.293, P < 0.1). However, subgroup analyses revealed that this positive effect was not significant among middle-aged and older adults who were divorced (ß = 0.190, P > 0.05), lived in special zone (ß = -1.379, P > 0.05), and lacked medical insurance (ß = 0.314, P > 0.05). Furthermore, mediation analysis revealed that inpatient services (ß = 0.0215, P < 0.01) acted as a mediator in the relationship between internet use and self-rated health. Conclusion: Internet use positively correlates with self-rated health among middle-aged and older adults. Additionally, the utilization of health services can significantly influence this relationship. These findings underscore the importance of developing targeted government strategies to promote internet access and create a supportive online environment, thereby enhancing the health outcomes of this demographic group.

[Relationship Between Physical Activity and Depressive Symptoms Among Middle-Aged and Older Adults in Chengdu,Sichuan,China].

Objective To investigate the current status of physical activity and depressive symptoms among middle-aged and older adults in Chengdu,Sichuan and explore the relationship between physical activity and depressive symptoms. Methods Multi-stage proportional stratified random sampling was employed to select middle-aged and older adults aged ≥45 years as the participants,and face-to-face interviews were carried out to collect data.Logistic regression was adopted to explore the relationship between physical activity and depressive symptoms in middle-aged and older adults.The trend test was performed for the relationship between different levels of physical activity and depressive symptoms.The subgroup analysis and the test for multiplicative interactions were conducted for the relationship between physical activity and depressive symptoms. Results A total of 4376 middle-aged and older adults were included.Among them,14.58% (638/4376),25.98% (1137/4376),and 27.83% (1218/4376) had depressive symptoms,failed to reach the guideline-recommended standards of physical activity,and were at low levels of physical activity,respectively.There was a negative association between reaching guideline-recommended physical activity standard and depressive symptoms in middle-aged and older adults (OR=0.713,95%CI=0.589-0.861,P<0.001).In addition,moderate levels (OR=0.714,95%CI=0.586-0.871,P=0.001) and high levels of physical activity (OR=0.705,95%CI=0.548-0.906,P=0.006) had negative associations with the presence of depressive symptoms.The trend test revealed that the negative association between physical activity and depressive symptoms in middle-aged and older adults enhanced as the level of physical activity increased (Pfor trend=0.001).The subgroup analysis and the test for multiplicative interactions revealed that neither reaching guideline-recommended physical activity standards or not nor the physical activity level had an interaction with each of the subgroups (all Pfor interaction>0.05). Conclusion The current status of depressive symptoms among middle-aged and older adults in Chengdu,Sichuan needs to be ameliorated.A negative association existed between reaching the guideline-recommended physical activity standard and presence of depressive symptoms,and the negative association enhanced as the physical activity level elevated.

Association between City-Level Particulate Matter Exposure and Frailty among Middle-Aged and Older Adults in China.

INTRODUCTION: The effects of exposure to particulate matter and frailty, as well as its exposure-response relationship, have not been effectively explored. This study aimed to explore the association between long-term exposure to particulate matter and frailty state and each dimension in Chinese middle-aged and older adults, in addition to the exposure-response relationship. METHODS: The data were obtained from the National Urban Air Quality Real-Time Dissemination Platform and China Health and Retirement Longitudinal Study (CHARLS). Frailty was measured by a frailty index containing 39 indicators. Annual averages of seven pollutants were calculated from hourly monitoring data. We used multilevel regression modeling to explore the association between long-term exposure to particulate matter and frailty. Meanwhile, we explored the exposure-response relationship based on a multilevel generalized summation model. We performed a sensitivity analysis using a multi-pollution model and a quantile-based g-computation (QGC) model. RESULTS: A total of 15,611 participants were included in the analysis. We find that long-term exposure to PM2.5 was associated with an increased risk of pre-frailty and frailty (all p < 0.05). PMc and PM10 exhibited similar associations. The exposure-response relationship between PM2.5 showed a linear relationship, whereas the exposure-response relationship between PM10, PMc showed a nonlinear relationship. Elevated PM2.5 concentrations showed significant positive associations with the number of chronic disease score, IADL score, and functional limitation status score (all p < 0.05). PM10 and PMc showed similar positive correlations. These results remained robust after sensitivity analyses using a multi-pollution model and QGC model. CONCLUSION: Chronic exposure to particulate matter was significantly associated with increased risk of frailty. The exposure-response relationship between PM2.5 concentration and frailty showed a linear relationship, and the exposure-response relationship between PM10 and PMc showed a nonlinear relationship. Exposure to a mixture of pollutants carried a higher risk of frailty than exposure to a single pollutant.

Association between long-term exposure to PM2.5 chemical components and metabolic syndrome in middle-aged and older adults.

Background: Previous studies indicated that exposure to ambient fine particulate matter (PM2.5) could increase the risk of metabolic syndrome (MetS). However, the specific impact of PM2.5 chemical components remains uncertain. Methods: A national cross-sectional study of 12,846 Chinese middle-aged and older adults was conducted. Satellite-based spatiotemporal models were employed to determine the 3-year average PM2.5 components exposure, including sulfates (SO4 2-), nitrates (NO3 -), ammonia (NH4 +), black carbon (BC), and organic matter (OM). Generalized linear models were used to investigate the associations of PM2.5 components with MetS and the components of MetS, and restricted cubic splines curves were used to establish the exposure-response relationships between PM2.5 components with MetS, as well as the components of MetS. Results: MetS risk increased by 35.1, 33.5, 33.6, 31.2, 32.4, and 31.4% for every inter-quartile range rise in PM2.5, SO4 2-, NO3 -, NH4 +, OM and BC, respectively. For MetS components, PM2.5 chemical components were associated with evaluated risks of central obesity, high blood pressure (high-BP), high fasting glucose (high-FBG), and low high-density lipoprotein cholesterol (low-HDL). Conclusion: This study indicated that exposure to PM2.5 components is related to increased risk of MetS and its components, including central obesity, high-BP, high-FBG, and low-HDL. Moreover, we found that the adverse effect of PM2.5 chemical components on MetS was more sensitive to people who were single, divorced, or widowed than married people.

How spousal cognitive functioning affects the level of depression in middle-aged and older adults: An instrumental variable study based on CHARLS in China.

A better understanding of the causal relationship between spousal cognitive functioning and depression levels among middle-aged and older adults is vital for effective health policymaking under the globally severe aging challenge. However, the related evidence is often limited by potential omitted-variable bias and reverse causation. This study uses an instrumental variables approach, namely the two-stage least squares (2SLS) method, to examine the impact of spousal cognitive functioning on depression levels among middle-aged and older adults in China. The data were sourced from the China Health and Retirement Longitudinal Study (CHARLS) of 2020, including a total of 3,710 couples aged 45 years and above. Depression levels were measured using the Center for Epidemiologic Studies Depression Scale (CES-D-10), while cognitive functioning was assessed using the Mini-Mental State Examination (MMSE). Spousal social participation was employed as the instrumental variable to address omitted-variable bias and reverse causation. Additionally, an interaction effect test between gender and spousal cognitive functioning was conducted. The results show that for each one-point increase in the spouse's MMSE score, the CES-D-10 score of middle-aged and older adults decreased by 17.1% to 68.2%. The OLS results indicated that women, rural residents, and middle-aged individuals were more sensitive to these changes. The interaction effect test results confirmed that women were more affected by changes in spousal cognitive functioning. However, after a more reliable 2SLS analysis, the results for age groups shifted, showing that middle-aged individuals were more sensitive to these changes, with a decrease in depression levels reaching 70.0%, compared to 60.2% for the elderly group. Nonetheless, given the prevalence of depression among the elderly, the impact of spousal cognitive decline on depression in this group should not be overlooked. Our findings highlight the importance of spousal cognitive health in managing depression among both middle-aged and older adults, with particular attention to women and rural populations.

Mediation analysis of cognitive function in the relationship between pulmonary function and depression among middle-aged and older adults.

AIM: This study aims to explore the association between declining lung function and depression in middle-aged and older adults, with a special focus on the mediating role of cognitive function. METHODS: This study utilizes self-reported and physical examination data from 5345 individuals participating in the 2015 cycle of the China Health and Retirement Longitudinal Study (CHARLS) to explore the role of cognitive function changes in mediating the effects of diminished lung function on depression among middle-aged and older adults. RESULTS: Multivariate linear regression analysis revealed a positive correlation between pulmonary and cognitive functions (ß = 0.003, 95% CI: 0.002∼0.003, P < 0.01) and a negative correlation between cognitive function and depression (ß = -0.279, 95% CI: -0.330-0.228, P < 0.01). Cognitive function plays a mediating role in linking pulmonary function with depression, exhibiting a mediation effect of -0.0007 and a total effect of -0.0046, wherein the mediation effect contributes to 15.22% of the total effect. For females, the mediating effect of cognitive function was stronger (ß = -0.0013, 95% CI: -0.0018∼-0.0008, P < 0.01) than it was for males (ß = -0.0006, 95% CI: -0.0009∼-0.0003, P < 0.01). CONCLUSIONS: The study underscores the importance of monitoring lung and cognitive functions as interconnected factors contributing to the mental health of middle-aged and older adults. It suggests that interventions aimed at improving pulmonary health and cognitive function may help mitigate depressive symptoms among middle-aged and older adults. Further research is warranted to validate these findings across diverse cultural and demographic settings. Geriatr Gerontol Int 2024; ••: ••-••.

Longitudinal associations between leisure activities and subjective happiness among middle-aged and older adults people in China: national cohort study.

Background: Leisure activities serve as key measures to enhance the subjective happiness of middle-aged and older adults individuals and to positively address the challenges of an aging society; however, the trajectory of changes in their participation in leisure activities and how these changes relate to shifts in subjective happiness have not been adequately explored. Methods: This study selected data from the China Health and Aging Longitudinal Study (CHARLS), which included a total of 5,190 middle-aged and older adults people. Linear and nonlinear latent growth models, parallel latent growth models and cross-lagged models were constructed to investigate the influence and lagged relationship between the trajectory of changes in the level of participation in leisure activities on the trajectory of changes in the subjective well-being of middle-aged and older adults people. Results: The initial level of physical activity participation of middle-aged and older adults people significantly predicted the initial level (ß = 1. 203, p < 0.001) and rate of change (ß = -0.138, p = 0.016) of their subjective well-being, and the trajectory of change of middle-aged and older adults people's physical activity also significantly predicted the rate of change of their subjective well-being (ß = 0.582, p = 0.003). Meanwhile, the initial level of social activity of middle-aged and older adults people also effectively predicted the initial level of their subjective well-being (ß = 0.048, p < 0.001). At the same time, the covariates (gender, age, level of education, marital status, chronic disease) also predicted the initial level and rate of change of leisure activity participation level and subjective well-being. Finally, the cross-lagged model test confirmed the predictive effect of leisure activity participation level on subjective well-being of middle-aged and older adults people. Conclusion: This study confirms that the level of participation in leisure activities of Chinese middle-aged and older adults people has a significant predictive effect on their subjective happiness and that there is a significant correlation between the trajectory of changes in the level of participation in leisure activities and the trajectory of changes in subjective happiness.

Dietary vitamin K intake is associated with decreased neurofilament light chain among middle-aged and older adults from the NHANES.

Purpose: Neurofilament-light chain (NfL) is associated with neurodegenerative diseases, which are increasingly prevalent with aging. Vitamin K has been shown a neuroprotective effect. Therefore, we aimed to explore the potential relationship between dietary vitamin K intake and serum NfL. Methods: This study was conducted on the 2013-2014 cycles of the National Health and Nutrition Examination Survey, a multi-site population-based study of the US general population. Serum NfL level was measured using a highly sensitive immunoassay. Dietary vitamin K intake was estimated from two-day dietary recall interviews, and its relationship with NfL was determined using linear regression models. Results: The study included a total of 1,533 participants with a median age of 46 years, comprising 801 women (52.2%) and 732 men (47.8%). The median dietary intake of vitamin K was 81.6 µg/d, and the median serum NfL was 12 pg./mL. After adjusting for potential confounding factors in the full model, individuals with higher dietary vitamin K intake had lower serum NfL levels (Q4 vs. Q1, ß = -4.92, 95%CI: -7.66, -2.19, p = 0.002). A non-linear negative dose-response association is found between dietary vitamin K intake and serum NfL levels (P for non-linearity = 0.008); this association reaches a plateau when the dietary vitamin K intake is higher than 200 µg/d. According to the results of stratified analysis, the relationship between dietary vitamin K intake and serum NfL levels was stronger in the population of middle-aged and older adults. Conclusion: The present study suggested a negative association between dietary vitamin K intake and serum NfL levels in the general US population, especially in middle-aged and older adults. This study might offer a novel nutritional idea for the primary prevention and mechanism exploration of neurodegenerative diseases.

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

Objective: To explore the trajectories of cognitive function development and predictive factors in disabled middle-aged and older adults. Methods: Utilizing data from 983 disabled middle-aged and older adults in the China Health and Retirement Longitudinal Study (CHARLS) from 2013 to 2020, latent growth mixture models were constructed to analyze the categories of cognitive function development trajectories and their predictive factors. Results: The cognitive function trajectories of the disabled middle-aged and older adults were classified into three categories: rapid decline (32.6%), Slow decline (36.1%), and Stable (31.2%). Multinomial logistic regression analysis identified age, gender, residence, education, marital status, household income, sleep duration, depression, hearing ability, and social participation as predictors of these trajectories. Conclusion: There is heterogeneity in the cognitive function development trajectories among disabled middle-aged and older adults. Healthcare professionals can implement targeted health management based on the characteristics of different groups to prevent the deterioration of cognitive function in this population.

Association between functional dependence and cardiovascular disease among middle-aged and older adults: Findings from the China health and retirement longitudinal study.

Background: The effect of different functional dependency types on cardiovascular disease (CVD) is largely unknown. Here, we aimed to investigate the association between functional dependence and CVD among middle-aged and older adults by conducting a cross-sectional and longitudinal study. Methods: The study sample comprised 16,459 individuals of ≥40 years (including 10,438 without CVD) who had participated in the 2011 China Health and Retirement Longitudinal Study (CHARLS). Functional dependence was categorized based on the "interval-of-need" method, while CVD was defined as physician-diagnosed heart disease or stroke. Cox proportional hazard regression was employed to assess the effects of functional dependence on CVD. Moreover, patients were grouped according to the functional status changes, and the impact of these changes on CVD was observed. Heterogeneity, subgroup, and interaction analyses were used to evaluate the consistency of the study findings. Finally, a mediation analysis was performed to estimate the potential mediation effects on the relationship between functional dependence and CVD risk. Results: CVD prevalence in the overall study population was 13.73 % (2260/16,459), while its prevalence among individuals with functional independence, low dependency, medium dependency, and high dependency was 9.60 % (1085/11,302), 14.25 % (119/835), 17.72 % (115/649), and 25.01 % (941/3763), respectively. Additionally, medium (odds ratio: 1.33, 95 % confidence interval: 1.06-1.68) and high functional dependency (1.55, 95 % CI: 1.38-1.75) were associated with CVD. A total of 2987 (28.62 %) participants with CVD were identified during the 9-year follow-up, with 4.85 % (145/2987) of the CVD cases being attributed to functional dependence. The individuals with medium (HR: 1.20, 95 % CI: 1.01-1.44) and high functional dependency (1.25, 95 % CI: 1.14-1.37) were more likely to develop CVD than their peers with functional independence. Furthermore, persistent functional dependence (HR: 1.72, 95 % CI: 1.52-1.94) and transition from functional independence to dependence (1.79, 95 % CI: 1.61-1.98) were associated with a higher CVD risk than continuous functional independence. Hypertension and diabetes may partially mediate CVD caused by functional dependence. Conclusion: Functional dependence is associated with high CVD risk. Therefore, appropriate healthcare attention must be directed towards functionally dependent populations to protect their cardiovascular health.

Socioeconomic status and depression in later life: longitudinal mediation effects of activities of daily living.

BACKGROUND: Socioeconomic status (SES) is associated with both depression and activities of daily living (ADL and IADL). However, the role of ADL as a biological mechanism in the relationship between SES and late-life depression, examined through longitudinal data, remains understudied. This study explored the longitudinal mediation effects of basic ADL or IADL on the SES-depression link in older adults. METHODS: Data from the China Health and Retirement Longitudinal Study (N = 4104) were utilized. Mediation analysis was performed using parallel process latent growth curve modeling. RESULTS: The average age of participants was 57.76 years, and 55.7% being females. Significant linear growth over time was observed in ADL, IADL, and depression. Adjusting for covariates, SES was positively linked to the initial levels (intercepts) of ADL (ßiADL=-0.100[-0.143, -0.057]), IADL (ßiIADL=-0.140[-0.185, -0.095]), and depression (ßiDEP=-0.103[-0.158, -0.048]). However, SES showed no significant correlation with the rate of change (slopes) in ADL, IADL, or depression (P > 0.05). The intercepts of ADL (ßiDEP = 0.566[0.503, 0.629]) and IADL (ßiDEP = 0.607[0.544, 0.670]) were positively correlated with the depression intercept but negatively with the depression slope. Conversely, the slopes of ADL and IADL were positively associated with the depression slope. These results suggest a negative indirect relationship between SES and the initial level of depression, but a positive indirect relationship with the rate of increase in depression through ADL (or IADL) intercept. CONCLUSIONS: Higher SES is associated with a lower initial risk of depression and ADL difficulties. However, this same higher SES may relate to a faster increase in ADL difficulties and depression among middle-aged and older adults. The findings underscore the need for increased governmental healthcare funding and improved healthcare accessibility. Additionally, maintaining adequate sleep and physical activity can help prevent disability and reduce depression risk later in life, particularly among older adults with lower SES.

The lifestyle of new middle-aged and older adults in Taiwan described by wearable device: age and gender differences.

Studies of lifestyle through comprehensive objective and subjective measurements of health outcomes are lacking. An examination of lifestyle factors in middle-aged and older adults in terms of age, gender, and the interaction effect of age and gender from physiological and psychological perspectives are imperative. Recent advances in technology such as actigraphy have facilitated objective measurements. This exploratory study contributes to research on age and gender interactions on circadian rhythm, physical activity, sleep, and psychological variables by employing wrist accelerometers to measure behavioral circadian rhythm objectively and by using questionnaires to assess psychological status subjectively. The data were drawn from 218 participants aged 50 and older from the "Middle-aged and older adults Chinese Health and Actigraphy in Taiwan (MOCHA-T)". The results: (1) older adult group is associated with declined physical activity (MVPA time 79.9 min VS. 107.9 min, p = .002), worse sleep efficiency (78.1% VS. 81.9%, p = .008), and earlier lifestyle (Acrophase 14.19 h VS. 14.69 h, p = .01) comparing to middle-aged group. (2) Women have a more regular lifestyle (Interdaily stability 0.6 VS. 051, p < 0.001), higher physical activity (MVPA time 105.7 min VS. 79.3 min, p = .004), and better sleep efficiency (81.6% VS. 77.8%, p = .011) than men. (3) Significant age-by-gender interactions existed in life satisfaction (p = .025), relative amplitude (p = .016), and total wake time (p = .038). Furthermore, aging was associated with significant increases in life satisfaction among men as well as significant decreases in relative amplitude and reductions in the total wake time among women. In conclusion, aging exerted differential effects on life satisfaction in men as well as relative amplitude and the total wake time in women. This result highlights disparities in lifestyle arising from interconnected social and biological challenges.

Mediating Effects of Information Access on Internet Use and Multidimensional Health Among Middle-Aged and Older Adults: Nationwide Cross-Sectional Study.

BACKGROUND: With the exacerbation of population aging, the health issues of middle-aged and older adults have increasingly become a focus of attention. The widespread use of the internet has created conditions for promoting the health of this demographic. However, little is known about the effects of information access in promoting the relationship between internet use and the health of middle-aged and older adults. OBJECTIVE: This study aims to examine the relationship between internet use and multidimensional health in middle-aged and older adults, as well as the mediating effect of information access. Moreover, this study will explore the relationship between other dimensions of internet use (purposes and frequency) and health. METHODS: Data were sourced from the China General Social Survey conducted in 2018. Health outcomes, including self-rated, physical, and mental health, were assessed using the 5-level self-rated health scale, the 5-level basic activities of daily living scale, and the 5-level depression scale, respectively. The ordinal logistic regression model was used to examine the relationship between internet use and health among middle-aged and older adults. Additionally, the Karlson-Holm-Breen decomposition method was used to examine the mediation effect of information access. To address endogeneity issues, the two-stage least squares approach was applied. RESULTS: In our sample, nearly half (n=3036, 46.3%) of the respondents use the internet. Regression analyses revealed that internet use was positively associated with self-rated health (odds ratio [OR] 1.55, 95% CI 1.39-1.74; P<.001), physical health (OR 1.39, 95% CI 1.25-1.56; P<.001), and mental health (OR 1.33, 95% CI 1.19-1.49; P<.001) of middle-aged and older adults. Various dimensions of internet use positively contribute to health. In addition, information access significantly mediated the relationship between internet use and self-rated health (ß=.28, 95% CI 0.23-0.32), physical health (ß=.40, 95% CI 0.35-0.45), and mental health (ß=.16, 95% CI 0.11-0.20). Furthermore, there were significant differences in the relationship between internet use and health among advantaged and disadvantaged groups. CONCLUSIONS: The study showed that different dimensions of internet use are associated with better self-rated health, better physical health, and better mental health in middle-aged and older adults. Information access mediates the relationship between internet use and health. This result emphasizes the significance of promoting internet access as a means to enhance the health of middle-aged and older adults in China.

The impact of internet device diversity on depressive symptoms among middle-aged and older adults in China: A cross-lagged model of social participation as the mediating role.

BACKGROUND: Depressive symptoms is more prevalent in middle-aged and older populations, and the development of Internet technology has brought new challenges and opportunities for the mental health of this group. This study aims to explore the bidirectional relationship between Internet device diversity and levels of depressive symptoms through longitudinal data analysis, as well as investigate the mediating role of social participation. METHODS: Data for the analysis was retrieved from the China Health and Retirement Longitudinal Study (CHARLS) in 2015, 2018, and 2020, which included 9259 middle-aged and older adults. The sum of the number of devices mentioned by each participant was calculated to assess the diversity of internet device use, a weighted total score of how frequently and to what extent individuals had participated in various social activities in the past month was calculated to measure the social engagement, and the Center for Epidemiological Studies Depression Scale was used to calculate depressive symptoms. A cross-lagged mediation model and bivariate correlation analysis were employed to examine the longitudinal relationships among depressive symptoms, internet device diversity, and social participation. Age, gender, highest education level, marital status, drinking status, smoking history, self-rated health, sleep duration, and chronic health conditions were adjusted as covariates. RESULTS: The results from the three waves of longitudinal data revealed mutual predictive relationships among internet device diversity, social participation, and depressive symptoms. The mediating effect was significant (ß = -0.612, 95 % CI -0.796 to -0.429), with significant gender differences observed. Furthermore, our findings indicated that social participation functioned as a protective factor against depressive symptoms, and the association between social participation and depressive symptoms was not a straightforward linear relationship. This suggests that participation in social activities (either high or low) is associated with a lower risk of depressive symptoms compared to no social participation, with no gender differences. CONCLUSIONS: This study suggests that there is a relationship between internet device diversity and lower levels of depressive symptoms among middle-aged and older adults in China. Social participation mediates the relationship between internet device diversity and depressive symptoms, and different levels of social engagement have different effects on depressive symptoms. It is recommended to increase support for social participation among middle-aged and older adults, strengthen structural social capital, and better leverage the use of the internet to reduce depressive symptoms levels and promote the physical and mental well-being of this population.

Internet access during COVID-19 and depressive symptoms in middle-aged and older adults: Evidence from a quasi-experimental study in China.

BACKGROUND: Amid the COVID-19 pandemic, the mental health of middle-aged and older adults has become an increasing concern, and the role of the internet in addressing this public health crisis has drawn the attention of researchers. This study evaluated the impact of internet access during COVID-19 on depressive symptoms among middle-aged and older adults. METHODS: Data were derived from China Health and Retirement Longitudinal Study (CHARLS) 2018 and 2020. Difference-in-differences analysis was performed to compare changes in depressive symptoms between the internet users during COVID-19 and those who didn't have access to the internet before and during the pandemic. RESULTS: We found that internet access during COVID-19 pandemic significantly reduced middle-aged and older adults' depressive symptoms. Further investigation identified the underlying mechanisms through which internet access helps in alleviating depressive symptoms by reducing the likelihood of experiencing negative emotions about COVID-19. Heterogeneity analyses showed that rural residents and middle-aged individuals benefited more from internet access during the pandemic. CONCLUSIONS: Since internet access can alleviate middle-aged and older adults' depressive symptoms amidst public health crisis, policy makers should focus on enhancing their access to the internet.