Chinese Longitudinal Healthy Longevity Survey Research Articles

Bidirectional and dynamic relationships between social isolation and frailty among older adults in China

ObjectiveThis study aimed to investigate the bidirectional and dynamic relationships between Social Isolation (SI) and frailty among older adults in China. MethodsUsing data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS), this study utilized a Generalized Cross-Lagged Model (GCLM) to examine the temporal interrelationships between SI and frailty among individuals aged 65 years and older. ResultsThe findings revealed significant bidirectional associations between SI and frailty among older adults in China. The GCLM identified strong temporal dynamics in the relationships between SI and frailty, with both effects increasing and showing a "cumulative disadvantage" effect as older adults aged. ConclusionThis study underscores the significance of tailored interventions aimed at mitigating both SI and frailty among older adults in China, thus addressing the bidirectional impact. The findings emphasize the necessity for early intervention strategies to counteract the cumulative disadvantages associated with SI and frailty in later-life outcomes.

Living arrangements, health lifestyles, and health outcomes among Chinese oldest-old.

Prior literature has documented a strong correlation between living arrangements and older adults' health outcomes. However, few studies have explained why this association exists. This study took the health lifestyle theory approach and brought health lifestyles into the link between living arrangements and Chinese oldest-old health outcomes. It examined (1) whether healthy lifestyle behaviors among the oldest-old varied by household contexts and (2) whether the health disparities among the Chinese oldest-old in different household contexts could be partially explained by their healthy lifestyles. Using the most recent 2018 data released by the Chinese Longitudinal Healthy Longevity Survey (CLHLS), latent class analysis was applied to identify predominant health lifestyles among the Chinese oldest-old aged 85-105 years. Regression analyses were used to test the mediating effect of health lifestyles. Three distinct classes representing the health lifestyles of Chinese oldest-old emerged; health lifestyle patterns were found to vary by elders' living arrangements. The respondent's health lifestyles in diverse residential structures served as a mediator which can partially explain the health disparities among the oldest-old. The results suggested that health lifestyles can serve as a mediator to explain the association between oldest-old living arrangement patterns and their health outcomes. The findings highlighted the importance of family, lifestyles, and cultural contexts to the health of the oldest-old.

Latent transition analysis to explore patterns of physical functional decline among older adults in China: A national 6-year longitudinal study

Background and aimsMultiple limitations often co-occur and accumulate, leading to subsequent function decline. However, there is a scarcity of longitudinal studies examining the progression of physical function among the general population of older adults in China. This study aimed to define typical physical function status and its change, which were characterized by the coexistence and accumulation of diverse limitations targeting a Chinese sample of older adults. MethodsThis study used the three recent public data waves of the Chinese Longitudinal Healthy Longevity Survey during a 6-year follow-up period. 9765 individuals who were over 65 and participated in the 2011 survey were included. Latent transition analysis was used to identify the latent physical function status and explore the transition of older adults among different latent statuses. ResultsSeven latent statuses of physical function were identified, with visual impairment and related limitations being particularly prevalent among older adults. Upper limb mobility appeared to be a differentiated indicator of physical functional status. Physical function decline mainly started with the limitations in squatting, carrying weights and walking, then to the status with intact upper limb mobility and hearing function only, or converted directly into the latter, then to complete dysfunction. ConclusionsOur findings suggest some indicative limitations and critical steps in the process of functional decline among older adults. These results may provide insight for researchers and policymakers to develop tailored preventive and rehabilitation care and provide support for physically limited elderly according to their latent status and course of functional decline.

Interrelation of Chronic Lung Disease and Cardiovascular Disease: Based on Two National Prospective Cohort Studies.

Chronic lung diseases (CLDs) and cardiovascular diseases (CVDs) are the main chronic diseases responsible for a considerable burden of disease. This study aimed to estimate the interrelation of CLDs and CVDs using two Chinese national longitudinal cohort studies. The China Health and Retirement Longitudinal Study (CHARLS) and Chinese Longitudinal Healthy Longevity Survey (CLHLS) were used in this study with 15,052 and 9,765 participants, respectively. The Cox proportional risk model was used to estimate the interrelation between CLDs and CVDs. Mediating effects were performed to detect possible influencing pathways between CLDs and CVDs. The association of CLDs with CVDs was identified in 1,647 participants (10.9%) with newly diagnosed CVDs in CHARLS and 332 participants (11.6%) in CLHLS. The Cox proportional risk model showed that CLDs were a significant predictor of CVDs (HR 1.49, 95% CI 1.27-1.76) after adjusting for covariates, and the hazard ratios of stroke and CVDs excluding stroke were (HR 1.02, 95% CI 0.79-1.31) and (HR 1.76, 95% CI 1.46-2.13), respectively. These association were mediated by body mass index (BMI) and Center for Epidemiological Studies Depression Scale (CES-D-10) scores. No significant association was found in CHARLS and CLHLS regarding CVDs with CLDs. In CHARLS, CVDs was a significant predictor of CLDs (HR 1.40, 95% CI 1.09-1.79). Chronic lung disease was associated with increased incidence of CVDs in middle-aged and older people in the community population and vice versa. Body mass index and depressive symptoms might be mediated by the effect of CLD on CVD.

Changes in physical activity and all-cause mortality in the oldest old population: Findings from the Chinese Longitudinal Healthy Longevity Survey (CLHLS)

BackgroundInsufficient or decreasing physical activity is common in older adults. Most studies on physical activity changes and mortality were conducted in adults younger than 80 years old in developed countries. We aimed to investigate the relationship between changes in physical activity and longevity in the oldest old (80 years or older) population using the Chinese Longitudinal Healthy Longevity Survey. MethodsParticipants aged 80 or older at baseline were categorized into four groups: 1) remaining physically inactive (n = 14,287), 2) remaining physically active (n = 5411), 3) shifting from being inactive to active (n = 1364), and 4) shifting from being active to inactive (n = 1401). We fitted accelerated failure time Weibull survival regression models, adjusting for baseline sociodemographics, lifestyle factors and disease status. We further examined whether the associations differed by subgroups. ResultsA total of 15,707 participants died during follow-up (median duration of follow-up = 3.0 years). Compared with participants who remained physically inactive, those who remained active (fully adjusted event time ratio (ETR): 1.14, 95%CI: 1.11–1.17) or shifted from being inactive to active (fully adjusted ETR: 1.14, 95%CI: 1.08–1.20) had statistically significant longer survival time. No significant association was observed between remaining physically inactive and shifting from being active to inactive. Subgroup analyses showed consistent associations in nearly all strata. ConclusionMaintaining frequent physical activity or shifting from being physically inactive to active was consistently associated with longer survival time in the oldest old population. Our findings provide evidence for encouraging older adults to regularly engage in physical activity to gain longevity benefits.

Healthy lifestyle in late-life, longevity genes, and life expectancy among older adults: a 20-year, population-based, prospective cohort study

Lifestyle and longevity genes have different and important roles in the human lifespan; however, the association between a healthy lifestyle in late-life and life expectancy mediated by genetic risk is yet to be elucidated. We aimed to investigate the associations of healthy lifestyle in late-life and genetic risk with life expectancy among older adults. A weighted healthy lifestyle score was constructed from the following variables: current non-smoking, non-harmful alcohol consumption, regular physical activity, and a healthy diet. Participants were recruited from the Chinese Longitudinal Healthy Longevity Survey, a prospective community-based cohort study that took place between 1998 and 2018. Eligible participants were aged 65 years and older with available information on lifestyle factors at baseline, and then were categorised into unhealthy (bottom tertile of the weighted healthy lifestyle score), intermediate (middle tertile), and healthy (top tertile) lifestyle groups. A genetic risk score was constructed based on 11 lifespan loci among 9633 participants, divided by the median and classified into low and high genetic risk groups. Stratified Cox proportional hazard regression was used to estimate the interaction between genetic and lifestyle factors on all-cause mortality risk. Between Jan 13, 1998, and Dec 31, 2018, 36 164 adults aged 65 years and older were recruited, among whom a total of 27 462 deaths were documented during a median follow-up of 3·12 years (IQR 1·62-5·94) and included in the lifestyle association analysis. Compared with the unhealthy lifestyle category, participants in the healthy lifestyle group had a lower all-cause mortality risk (hazard ratio [HR] 0·56 [95% CI 0·54-0·57]; p<0·0001). The highest mortality risk was observed in individuals in the high genetic risk and unhealthy lifestyle group (HR 1·80 [95% CI 1·63-1·98]; p<0·0001). The absolute risk reduction was greater for participants in the high genetic risk group. A healthy lifestyle was associated with a gain of 3·84 years (95% CI 3·05-4·64) at the age of 65 years in the low genetic risk group, and 4·35 years (3·70-5·06) in the high genetic risk group. A healthy lifestyle, even in late-life, was associated with lower mortality risk and longer life expectancy among Chinese older adults, highlighting the importance of a healthy lifestyle in extending the lifespan, especially for individuals with high genetic risk. National Natural Science Foundation of China. For the Mandarin translation of the abstract see Supplementary Materials section.

Association Between Living Arrangements and Psychological Well-Being Among Older Adults in Rural China: Activities of Daily Living Disability as a Moderator

This study investigated the association between living arrangements and psychological well-being (PWB) among older adults in rural China and whether activities of daily living (ADL) disability moderate this association. The study data were drawn from the sixth to eighth waves of the Chinese Longitudinal Healthy Longevity Survey. The baseline sample included 4,042 individuals aged 65 years and above. PWB was measured using seven mood-related and personality-related questions. ADL disability was measured using Katz’s 6 items of ADL. Living arrangements were categorized into six categories. Linear mixed-effect models were used to examine the association between older adults’ living arrangements and PWB as well as the moderating effect of ADL disability on this relationship. The results showed that compared with living alone, living with spouse only, and living with spouse and children were positively associated with PWB (β = .621, p &lt; .01; β = .527, p &lt; .05), and living with children (no spouse) was negatively associated with PWB (β = −.564, p &lt; .001). ADL disability was negatively associated with PWB (β = −.457, p &lt; .01). Living with children (no spouse) × ADL disability had a positive interaction effect (β = .278, p &lt; .05). These findings suggest that living alone and living with children (no spouse) are not conducive to PWB among older adults in rural China, and ADL disability reduces the negative effects of living with children (no spouse) on PWB. Our findings provide a crucial direction for PWB interventions aimed at older adults in rural China.

Changing Trends and the Effectiveness of Informal Care Among Rural Elderly Adults in China

The economic and social transformation of rural areas, coupled with the decline of family-based elderly care and increasing health risks, necessitates in-depth research on the effectiveness of informal care for rural elderly adults. Utilizing 10-year, four-period follow-up data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) between 2008 and 2018, this study empirically examines the changing trends and heterogeneity of informal care. In addition, this paper identifies factors impacting on the satisfaction of rural informal care services, providing a comprehensive understanding of the effectiveness of these services for different segments of the rural elderly adults. The results indicate that the changing trends of informal care for rural elderly adults follows a differential pattern, with over 60% relying on their children, and 7.79% to 13.27% on their spouses. Only a small fraction of elderly individuals relies on institutional care and market-oriented care, with percentages below 2% and 3%, respectively. While over 95% of rural elderly adults express satisfaction with their informal care services, less than 50% are fully satisfied, and the proportion of dissatisfied elderly adults is increasing annually. Key variables impacting on the effectiveness of informal care services include marital status, health status, living arrangement, care intensity, care expenditures, pension insurance, and daily community care support. Policy options such as financial support for informal care, enhancement of the old-age security system, and the establishment socialized formal care can help alleviate the burden of informal care for rural elderly adults.

Community-based service, psychological resilience and life satisfaction among Chinese older adults: A longitudinal study

Previous research has suggested that community-based service is beneficial in promoting older adults’ life satisfaction. However, there is limited knowledge of the mediating mechanisms that foster this relationship. Thus, the current study aims to explore the mediating role of psychological resilience in the association between community-based service and life satisfaction among older adults. Using data collected over four rounds of the Chinese Longitudinal Healthy Longevity Survey (CLHLS), this study analyzes the responses of 1439 older adults in China. The results reveal that community-based service is positively related to life satisfaction among older adults. Furthermore, psychological resilience partially mediates this association, highlighting its potential role in promoting life satisfaction. These findings contribute to a deeper theoretical understanding of the mechanisms underlying the relationship between community-based service and older adults’ life satisfaction while offering practical implications for enhancing the life satisfaction of older adults in China.

The Association Between Trajectories of Perceived Unmet Needs for Home and Community-Based Services and Life Satisfaction Among Chinese Older Adults: The Moderating Effect of Psychological Resilience.

This study examined whether trajectories of perceived unmet needs for Home and Community-Based Services (HCBS) were associated with life satisfaction among Chinese older adults and whether the association was moderated by psychological resilience. Data came from five waves (2005-2018) of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Latent class growth analysis revealed three distinct trajectories of perceived unmet HCBS needs: "increasing" (n = 977, 36.24%), "persistent" (n = 570, 21.14%), and "decreasing" (n = 1149, 42.62%). Multiple regression estimates showed that the increasing group was associated with lower life satisfaction, and the association was moderated by psychological resilience, especially for older adults who were male, living in rural, and oldest-old. Results indicate that inequalities in cumulative exposure to perceived unmet HCBS needs may further lead to increasing inequalities in life satisfaction. Interventions focused on minimizing the provision-need gap of HCBS and enhancing personal resilience should be considered to improve the life satisfaction of older adults.

Serum Vitamin D3 Concentration, Sleep, and Cognitive Impairment among Older Adults in China.

Cognitive decline in older adults has become one of the critical challenges to global health. This study aims to examine both cross-sectional and longitudinal associations of levels of serum 25-hydroxyvitamin D3 (25(OH)D3) (briefed as VD3) concentration and sleep quality/duration, especially their interactions, with risk of cognitive impairment among older adults in China. We utilized a special subsample of adults aged 65-105 years (individuals = 3412, observations = 4816) from eight provinces in China derived from the 2011/2012 and 2014 waves of the Chinese Longitudinal Healthy Longevity Survey. Cognitive impairment was measured by the Mini-Mental State Examination scale. Sleep quality was classified as good versus fair/poor, and sleep duration was classified into short (<7 h), normal (≥7 but <9 h), and long (≥9 h). The VD3 concentration was divided into three levels: deficiency (VD3 < 25 nmol/L), insufficiency (25 nmol/L ≤ VD3 < 50 nmol/L), and sufficiency (VD3 ≥ 50 nmol/L). A wide set of covariates that include demographics, socioeconomic status, family support, health practice, and health conditions was adjusted for robust findings. Multilevel random intercept logit regression models were used to examine the cross-sectional associations between VD3, sleep, and cognitive impairment, whereas logit regression models were applied to investigate the longitudinal associations. In the cross-sectional analyses, when all covariates were adjusted, VD3 sufficiency was significantly associated with a 33% lower risk of cognitive impairment compared with VD3 deficiency; good sleep quality was associated with 34% lower odds of cognitive impairment compared with fair/poor sleep quality; sleep hours were not associated with cognitive impairment, although a long sleep duration (≥9 h) was associated with 30% higher odds of being cognitively impaired when baseline health was not controlled. Interaction analyses reveal that VD3 sufficiency could help to additionally reduce the risk of cognitive impairment for good sleep quality and normal sleep hours. In the longitudinal analyses, the association of VD3 sufficiency remains significant, whereas sleep quality and sleep duration were not significant associates. Good sleep quality, normal sleep hours, and VD3 sufficiency are positively associated with good cognitive function. VD3 sufficiency could enhance the associations between sleep and cognitive impairment.

Living arrangements and depression of the older adults– evidence from the Chinese longitudinal healthy longevity survey

BackgroundThe mental health and living arrangements of older adults are worthy of attention. Previous studies have pointed out that the living arrangements may be related to older adults’ depression. However, it has not been found that studies concern the relationship between actual living arrangements, living arrangement preferences, and the fit between living arrangement preferences and reality and depression in older adults, so we carried out this study.MethodsThe data from the Chinese longitudinal healthy longevity survey were used in this study. With the older adults’ depression as the dependent variable and the living arrangement related variables as the independent variable, we constructed three binary-logistic regression analysis models to explore the potential relationship between living arrangement related variables and depression in older adults.ResultsWe found that the actual living arrangements, living arrangement preferences, and the fit between living arrangement preferences and reality are significantly correlated with depression in older adults. Specifically, older adults living alone or only with the spouse are at greater risk of depression. Older adults who prefer living alone or only with the spouse are at relatively low risk of depression. Older adults whose living arrangement preferences do not match reality have a higher risk of depression.ConclusionThe living arrangement related variables are significantly correlated with depression in older adults. In addition to the actual living arrangements, living arrangement preferences and whether the living arrangement preferences fit with reality are also related to the depression of older adults.

Hypotension and cognitive impairment among the elderly: Evidence from the CLHLS.

While high blood pressure has been linked to cognitive impairment, the relationship between low blood pressure, especially hypotension, and cognitive impairment has not been well studied. Therefore, this study aimed to assess the prevalence of hypotension and cognitive impairment in the seniors of China, and the association between hypotension and cognitive function impairment. The data was derived from the 2018 wave of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Systolic blood pressures (SBP) and diastolic blood pressures (DBP) were measured by objective examination. The Chinese version of the Mini-Mental State Examination (CMMSE) was used to evaluate the cognitive impairment of the elderly. Generalized linear models were conducted to evaluate the association of hypotension with cognitive impairment. The prevalence of hypotension and cognitive impairment in the Chinese elderly were 0.76% and 22.06%, respectively. Participants with hypotension, lower SBP, and lower DBP, had odds ratios of 1.62, 1.38, and 1.48 for cognitive impairment, respectively. Besides, the CMMSE scores decreased by 2.08, 0.86, and 1.08 in the elderly with hypotension, lower SBP, and DBP, compared with those with non-hypotension, higher SBP, and DBP, respectively. Subgroup analyses showed that the association of cognitive impairment with hypotension was stronger in Chinese elderly who had decreased activity of daily living. Moreover, there was statistical evidence of a nonlinear dose-response relationship of SBP and DBP with cognitive impairment (Pnonlinear < 0.05). Hypotension was a potential risk factor for cognitive impairment of the Chinese elderly, especially for those having decreased activity of daily living. Blood pressure management should be conducted to prevent them from cognitive impairment.

Association of living arrangements with all-cause mortality among older adults: a propensity score–matched cohort study

BackgroundMany studies exist on the living arrangements and health status of older adults, but the findings have been inconsistent. Therefore, we examined the relationship between living arrangements and all-cause mortality in older adults.MethodsThis perspective study was based on the Chinese Longitudinal Healthy Longevity Survey (CLHLS) from 2011 to 2018. We used a sample aged 65 years and over included in the study in 2011. Propensity score matching was performed to minimize bias and Cox proportional hazards regression models were conducted.ResultsA total of 7,963 participants were included. Of these, 1,383 were living alone, 6,424 were living with families, and 156 were living in nursing homes. In the propensity score-matched cohort, older adults living alone had a significantly lower risk of all-cause mortality than those living with families (hazard ratio 0.85; 95% confidence intervals 0.76 to 0.95). Living alone was prominently associated with a decline in mortality compared with living in nursing homes (hazard ratio 0.61; 95% confidence intervals 0.44 to 0.84). There was no significant difference in mortality between living in nursing homes and living with families (hazard ratio 1.19; 95% confidence intervals 0.89 to 1.60). Subgroup analyses indicated that there was no significant interaction with age, sex, education, or residence.ConclusionsThe risk of all-cause mortality was significantly lower in older adults living alone than in those living with families or living in nursing homes. This article’s findings suggest the need to adopt multiple approaches to meet the needs of senior care services.

Impact of access to childhood health services on healthy life expectancy of the older population.

Life course theory provides new perspectives on the impact of early experiences on health in old age, where unfortunate childhood experiences can alter an individual's health trajectory. This study aims to calculate the healthy life expectancy of the older population in China under different childhood experiences, and to explore the influence of childhood medical and health services on the health level of older adults. Differences in healthy life expectancy of the older population under different childhood experiences were analyzed using the multi-state life table method to calculate the healthy life expectancy by sex and place of birth, based on the cohort data of Chinese Longitudinal Healthy Longevity Survey (CLHLS) from 2008 to 2018. The probability of the transition risk from health to non-health gradually increased with age, while the probability of the transition risk from non-health to health decreased with age; In both urban and rural areas, on the probability of the transition risk from health to non-health, the older adults who were able to receive timely medical and health services in childhood were lower than those who failed to receive medical services in time (Z = -5.833, P < 0.05), but the probability of the transition risk from non-health to health was the opposite (Z = -5.334, P < 0.05); The probability of the transition risk from health to death is also higher in older adults who were unable to receive timely medical care in childhood (Z = -5.88, P < 0.05); The healthy life expectancy and its proportion in the remaining life expectancy of older people who received medical and health services in time during childhood were significantly higher than those of their peers (Z = -5.88, P < 0.05). The lack of medical services in childhood has a negative effect on the health of older adults. The healthy life expectancy and its proportion of remaining life expectancy were higher for rural older adults than for urban older adults under the same health care conditions in childhood; the health benefits of good access to health care environment or conditions in childhood were greater for rural older females.

Sociodemographic Factors Predict Incident Mild Cognitive Impairment: A Brief Review and Empirical Study

ObjectivesMild cognitive impairment (MCI) is a transitional stage between normal cognitive aging and dementia that increases the risk of progressive cognitive decline. Early prediction of MCI could be beneficial for identifying vulnerable individuals in the community and planning primary and secondary prevention to reduce the incidence of MCI. DesignA narrative review and cohort study. Setting and ParticipantsWe review the MCI prediction based on the assessment of sociodemographic factors. We included participants from 3 surveys: 8915 from wave 2011/2012 of the China Health and Retirement Longitudinal Study (CHARLS), 9765 from the 2011 Chinese Longitudinal Healthy Longevity Survey (CLHLS), and 1823 from the 2014 Rugao Longevity and Ageing Study (RuLAS). MethodsWe searched in PubMed, Embase, and Web of Science Core Collection between January 1, 2019, and December 30, 2022. To construct the composite risk score, a multivariate Cox proportional hazards regression model was used. The performance of the score was assessed using receiver operating characteristic (ROC) curves. Furthermore, the composite risk score was validated in 2 longitudinal cohorts, CLHLS and RuLAS. ResultsWe concluded on 20 articles from 892 available. The results suggested that the previous models suffered from several defects, including overreliance on cross-sectional data, low predictive utility, inconvenient measurement, and inapplicability to developing countries. Our empirical work suggested that the area under the curve for a 5-year MCI prediction was 0.861 in CHARLS, 0.797 in CLHLS, and 0.823 in RuLAS. We designed a publicly available online tool for this composite risk score. Conclusions and ImplicationsAttention to these sociodemographic factors related to the incidence of MCI can be beneficially incorporated into the current work, which will set the stage for better early prediction of MCI before its incidence and for reducing the burden of the disease.

Predicting unmet activities of daily living needs among the oldest old with disabilities in China: a machine learning approach.

The ageing population in China has led to a significant increase in the number of older persons with disabilities. These individuals face substantial challenges in accessing adequate activities of daily living (ADL) assistance. Unmet ADL needs among this population can result in severe health consequences and strain an already burdened care system. This study aims to identify the factors influencing unmet ADL needs of the oldest old (those aged 80 and above) with disabilities using six machine learning methods. Drawing from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) 2017-2018 data, we employed six machine learning methods to predict unmet ADL needs among the oldest old with disabilities. The predictive effects of various factors on unmet ADL needs were explored using Shapley Additive exPlanations (SHAP). The Random Forest model showed the highest prediction accuracy among the six machine learning methods tested. SHAP analysis based on the Random Forest model revealed that factors such as household registration, disability class, economic rank, self-rated health, caregiver willingness, perceived control, economic satisfaction, pension, educational attainment, financial support given to children, living arrangement, number of children, and primary caregiver played significant roles in the unmet ADL needs of the oldest old with disabilities. Our study highlights the importance of socioeconomic factors (e.g., household registration and economic rank), health status (e.g., disability class and self-rated health), and caregiving relationship factors (e.g., caregiver willingness and perceived control) in reducing unmet ADL needs among the oldest old with disabilities in China. Government interventions aimed at bridging the urban-rural divide, targeting groups with deteriorating health status, and enhancing caregiver skills are essential for ensuring the well-being of this vulnerable population. These findings can inform policy decisions and interventions to better address the unmet ADL needs among the oldest old with disabilities.

Association of waist-calf circumference ratio, waist circumference, calf circumference, and body mass index with all-cause and cause-specific mortality in older adults: a cohort study

BackgroundWaist circumference (WC), calf circumference (CC), and body mass index (BMI) have been independently linked to mortality. However, it's not yet clear how the waist-calf circumference ratio (WCR) relates to mortality. This study aims to investigate the relationship between WCR, WC, CC, and BMI with all-cause and cause-specific mortality in older adults.MethodsIn the 2014 Chinese Longitudinal Healthy Longevity Survey, 4627 participants aged 65 years and older were included, and they were subsequently followed up in 2018. Cox proportional hazards models were utilized to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause and cause-specific mortality, based on WCR, WC, CC, and BMI.ResultsDuring a median follow-up of 3.4 years, 1671 deaths (36.1%) occurred. Compared to the second quartile of WCR, the highest quartile had a higher risk of mortality from all causes (HR 1.42, 95%CI 1.24–1.64), cardiovascular disease (CVD) (HR 1.88, 95%CI 1.38–2.56), and other causes (HR 1.37, 95%CI 1.15–1.63). The first and fourth quartiles of WC had HRs of 2.19 (1.00–4.79) and 2.69 (1.23–5.89), respectively, for cancer mortality. The highest quartile of CC was associated with a lower risk of all-cause and other-cause mortality, whereas the lowest quartile was associated with a higher risk of all-cause, CVD, and other-cause mortality compared to the second CC quartile. Additionally, the lowest quartile of BMI was associated with a higher risk of all-cause and respiratory disease mortality. Interaction analyses showed that the effects of CC on all-cause and CVD mortality were more pronounced in adults aged ≥ 80 years (P-interaction < .05).ConclusionsHigher WCR and lower CC increased the risk of all-cause, CVD, and other-cause mortality. Lower BMI was associated with higher all-cause and respiratory disease mortality risk, while WC only predicted cancer mortality.

Urban overall and visible greenness and diabetes among older adults in China

Neighborhood greenness has been shown to reduce diabetes risk, however, no studies have compared the effects of overall greenness with visible greenness, which is crucial for understanding how greenness influences diabetes risk. Our study aims to explore the associations between greenness matrix and diabetes, as well as the potential effect modifications and mediating factors. We used logistic regressions to examine the cross-sectional associations of the satellite-based Normalized Difference Vegetation Index (NDVI) and street view-based Green View Index (GVI) with diabetes in 3,924 urban older adults enrolled in the 2017–2018 wave of Chinese Longitudinal Healthy Longevity Survey (CLHLS). We conducted the stratified analyses by age, sex, household income and education. Mediation analyses were also performed to see whether physical activity, BMI, air pollution, and social interaction mediate the associations. Significant associations with diabetes were only observed for NDVI but not for GVI. Participants in the highest quartile of NDVI and GVI had 52% (95 % CI: 48%, 63%) and 14% (-10%, 44%) lower odds of reporting having diabetes diagnosed by a doctor. The protective effects of NDVI were more pronounced in the young old (≥75–95 years) and high-education or high-income groups. No difference between males and females were observed. Air pollution (e.g., PM2.5, NO2 and O3) partially mediated the associations, but physical activity, BMI, and social interaction may not mediate the associations. Our findings indicate beneficial associations between overall greenness but not visible greenness surrounding residences with diabetes in older urban residents in China, especially for old adults with higher education or household income levels. Environmental factors (e.g., air pollution) but not individual behavioural characteristics are the potential underlying mechanisms.

The Dunning–Kruger effect: subjective health perceptions on smoking behavior among older Chinese adults

BackgroundThe intrinsic damage and external hazards of smoking are major risk factors for poorer health and are recognized as a global health issue of concern in geriatric health. This study aims to assess the Dunning–Kruger effect through the influence of subjective health perceptions on smoking behavior in older adults.MethodsThis study used data from the 2018 Chinese Longitudinal Healthy Longevity Survey (N = 9,683) provided by the Center for Healthy Aging and Development Studies at Peking University. A binary logistic model was used to examine whether the Dunning–Kruger effect affects smoking behavior in older adults, and a linear probability model was used as a commentary baseline model for logistic regression to prevent measurement bias. In addition, a mediating analysis was used to examine the mechanisms through which the Dunning–Kruger effect occurs.ResultsOlder adults often overestimated their current health status and underestimated the health risks of smoking, causing the Dunning–Kruger effect to arise from their inadequate self-perceived health (i.e., older adults are more likely to smoke when they have better self-rated health or when hypertension, cardiopathy, stroke, and diabetes have little or no impact on their daily lives). These observations can be explained by the older adults’ subjective health perceptions arising from their ingenuous understanding of their health, which indirectly influences their smoking behavior to some extent.ConclusionOlder adults’ self-perceived health was associated with smoking behavior. Public health institutions should improve older adults’ health perceptions so that they objectively understand their own health status.