Cognitive functioning transitions, health expectancies, and inequalities among elderly people in China: A nationwide longitudinal study

A Multi-State Model Study of the Disability-Free Life Expectancy Among Older Adults with Chronic Multimorbidity Based on CHARLS - China, 2011-2020

What is already known about this topic?

Chronic disease multimorbidity is prevalent among older Chinese people, seriously affecting their well-being and quality of life.

What is added by this report?

This study estimated the impact of multimorbidity on the risk of health state transitions and health expectancy among older adults in China. It used population-representative, long-term longitudinal data and multi-state Markov modeling along with microsimulation methods.

What are the implications for public health practice?

The study results suggest that the Chinese government should strengthen the prevention and management of multimorbidity and accelerate the transition from chronic disease management to multimorbidity management.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

Urbanicity-Perspectives from Neuroscience and Public Health: A Scoping Review

Urban residency is associated with exposure to environmental factors, which can influence health in many ways. Neuroscientific research, as well as Public Health research, aim towards broadening evidence in the field of Urban Health. However, it is unclear whether the association between urban living and mental illnesses is causal rather than explainable by other selective effects. This review seeks to gather information on the current evidence regarding urban living and neurological outcomes to demonstrate how Public Health and Neuroscience could complement each other in the field of Urban Health. A scoping review was conducted in four electronic databases according to the PRISMA-statement guidelines. 25 empirical studies were included. Outcomes such as schizophrenia and psychotic disorders, social and cognitive functioning were scrutinised. Evidence was found for alteration of brain functioning and brain structure. Most studies researching cognitive functioning or cognitive decline displayed possible protective effects of urban living compared to rural living. The different study designs in Public Health and Neuroscience could profit from each other. Although the comparability of studies is limited by the inconsistent assessments of urbanity. Synergies and potentials to combine aspects of Public Health and Neuroscience in the field of Urban Health to improve population health became apparent.

Socioeconomic Disparities in Disability-Free Life Expectancy and Life Expectancy Among Older Chinese Adults From a 7-Year Prospective Cohort Study

Objectives: We examined the magnitude and determinants of socioeconomic disparities in disability-free life expectancy and life expectancy at age 65 (DFLE₆₅ and LE₆₅) in China.

Methods: Data from Chinese Longitudinal Healthy Longevity Survey collected during 2011–2018 (8,184 participants aged ≥65) were used. Socioeconomic status (SES) was measured by economic status (ES), and education, respectively. Multistate Markov models and microsimulations were fitted to estimate DFLE₆₅ and LE₆₅.

Results: LE₆₅ between high- and low-ES groups differed by 2.20 years for males and 2.04 years for females. The DFLE₆₅ disparity in ES was 1.51 and 1.29 years for males and females, respectively. Not undergoing physical examinations, inadequate fruit/vegetable intake, and stress contributed to 35.10% and 57.36% of DFLE₆₅ disparity in ES, as well as 26.36% and 42.65% of LE₆₅ disparity for males and females, respectively. These disparities in education and ES were of a similar magnitude, while the above factors contributed little to education disparity.

Conclusion: Socioeconomic disparities in DFLE₆₅ and LE₆₅ existed in China. Physical examination, fruit/vegetable intake and stress partly explained these disparities.

Derivation and Validation of the Cognitive Impairment Prediction Model in Older Adults: A National Cohort Study

Objective

This prediction model quantifies the risk of cognitive impairment. This aim of this study was to develop and validate a prediction model to calculate the 6-year risk of cognitive impairment.

Methods

Participants from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) 2008–2014 and 2011–2018 surveys were included for developing the cognitive impairment prediction model. The least absolute shrinkage and selection operator, clinical knowledge, and previous experience were performed to select predictors. The Cox proportional hazard model and Fine-Gray analysis adjusting for death were conducted to construct the model. The discriminative ability was measured using C-statistics. The model was evaluated externally using the temporal validation method via the CLHLS 2002–2008 survey. A nomogram was conducted to enhance the practical use. The population attributable fraction was calculated.

Results

A total of 10,053 older adults were included for model development. During a median of 5.68 years, 1,750 (17.4%) participants experienced cognitive impairment. Eight easy-to-obtain predictors were used to develop the model. The overall proportion of death was 43.3%. The effect of age on cognitive impairment reduced after adjusting the competing risk of death. The Cox and Fine–Gray models showed a similar discriminative ability, with average C-statistics of 0.71 and 0.69 in development and external validation datasets, respectively. The model performed better in younger older adults (65–74 years). The proportion of 6-year cognitive impairment due to modifiable risk factors was 47.7%.

Conclusion

This model could be used to identify older adults aged 65 years and above at high risk of cognitive impairment and initiate timely interventions on modifiable factors to prevent nearly half of dementia.

Future life expectancy with disability among elderly Chinese individuals: a forecast based on trends in stroke and dementia

OBJECTIVES

This study aims to predict the life expectancy with disability (LED) of the elderly in China from 2010 to 2030 based on trends in stroke and dementia.

STUDY DESIGN

This was a prospective cohort study.

METHODS

Data for 28,667 eligible individuals aged 65+ years were derived from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) from 2002 to 2014. A discrete-time probabilistic Markov model was constructed with nine different health states characterized by the presence or absence of stroke, dementia, disability, or death. Binomial logistic regression was used to estimate the probability of state transition every 3 years based on the survey interval in the CLHLS. The number of disabled individuals was predicted in 2030 using Chinese population data from World Population Prospects 2019 and trends in the incidence and mortality for stroke and dementia as recorded in the CLHLS. A multistate life table was used to predict LED in 2030.

RESULTS

It is predicted that disability in those aged 65+ years in China will increase from 11.4 million in 2010 to 34.8 million in 2030. Cases associated with stroke and dementia are predicted to increase by 297.9% and 167.8%, respectively, for the 65-79 years age group, and by 402.1% and 247.0%, respectively, for the 80+ year age group. Life expectancy (LE) and LED for 65-year-old individuals are predicted to be 16.1 and 2.2 years in 2030, respectively, with increases of 11.8% and 57.1%, respectively.

CONCLUSIONS

LED in the elderly is predicted to increase more rapidly than LE from 2010 to 2030, both stroke and dementia increasing the risk of disability.

Inequalities in cognitive impairment among older adults in China and the associated social determinants: a decomposition approach

Background

Despite there is growing evidence focusing on health inequalities in China, socioeconomic inequalities in cognitive impairment among older adults have received little attention. This study aims to measure socioeconomic inequalities in cognitive impairment among Chinese older adults, and determine the contributing social factors to the inequalities.

Methods

A cross-sectional analysis was performed using data from the 2018 Chinese Longitudinal Healthy Longevity Survey (CLHLS). A total of 10,556 older adults aged 65 and over were included in the study. The prevalence of cognitive impairment was measured by using the Chinese version of the Mini-Mental State Examination. The socioeconomic inequalities in cognitive impairment were illustrated and quantified by the concentration curve and normalized concentration index. Multivariate logistic regression was conducted to identify the associated factors of cognitive impairment. And decomposition analysis was further applied to decompose the contribution of each determinant to the observed inequalities in cognitive impairment.

Results

The study indicated that the prevalence of cognitive impairment among Chinese older adults was 18.95%. The overall concentration index for cognitive impairment was − 0.046, which suggested a higher concentration of cognitive impairment among socioeconomically disadvantaged older adults. The results showed the prevalence of cognitive impairment was associated with sex, age, marital status, education level, occupation, economic status, emotional support, financial support, living arrangement, and participation in informal activities. Decomposition results further revealed the contributions of the determinants to the inequalities in cognitive impairment. Specifically, age (131.61%), marital status (85.68%), emotional support (84.85%), education level (39.73%), occupation (21.24%), sex (17.25%), financial support (− 4.19%), economic status (1.02%), living arrangement (0.88%), and informal activities (0.30%) have varying degrees of contributions to the inequality in cognitive impairment.

Conclusion

This study sheds light on the pro-rich inequality in cognitive impairment among older adults in China. It suggests that policymakers should pay more attention to older adults who are female, old-old, widowed, illiterate, economically disadvantaged, with no social support, and less socially involved. Also, more targeted interventions should be undertaken to improve the socioeconomic conditions of these vulnerable individuals and strengthen their ability to cope with the risk of cognitive impairment.

Trajectories of cognitive function and their determinants in older people: 12 years of follow-up in the Chinese Longitudinal Healthy Longevity Survey

BACKGROUND

Cognitive decline in advanced age is closely related to dementia. The trajectory of cognitive function in older Chinese is yet to be fully investigated. We aimed to investigate the trajectories of cognitive function in a nationally representative sample of older people living in China and to explore the potential determinants of these trajectories.

METHODS

This study included 2,038 cognitively healthy persons aged 65-104 years at their first observation in the Chinese Longitudinal Healthy Longevity Survey from 2002 to 2014. Cognitive function was measured using the Chinese version of the Mini-Mental State Examination (MMSE). Group-based trajectory modeling was used to identify potential heterogeneity of longitudinal changes over the 12 years and to investigate associations between baseline predictors of group membership and these trajectories.

RESULTS

Three trajectories were identified according to the following types of changes in MMSE scores: slow decline (14.0%), rapid decline (4.5%), and stable function (81.5%). Older age, female gender, having no schooling, a low frequency of leisure activity, and a low baseline MMSE score were associated with the slow decline trajectory. Older age, body mass index (BMI) less than 18.5 kg/m2, and having more than one cardiovascular disease (CVD) were associated with the rapid decline trajectory.

CONCLUSION

Three trajectories of cognitive function were identified in the older Chinese population. The identified determinants of these trajectories could be targeted for developing prevention and intervention strategies for dementia.

Frailty syndrome and cognitive impairment in older adults: systematic review of the literature

OBJECTIVE

to synthesize the knowledge about the association of frailty syndrome and cognitive impairment in older adults.

METHOD

the Joanna Briggs Institute's systematic review of etiology and risk factors was adopted. The search for the studies was conducted by two independent reviewers in the databases MEDLINE, Embase, CINAHL and LILACS and by manual search was performed by tow reviewers independently. The measures of association Odds Ratio and Relative Risk were used in the meta-analysis. The software R version 3.4.3 and the meta-analysis package Metafor 2.0 were used for figure analysis.

RESULTS

three studies identified the association of frailty syndrome and cognitive impairment through Odds Ratio values show that frail older adults are 1.4 times more likely to present cognitive impairment than non-frail older adults. Four studies analyzed the association through the measure of Relative Risk and found no statistical significance, and four studies used mean values.

CONCLUSION

despite of the methodological differences of the studies and the lack of definition of an exact proportion in the cause and effect relationship, most studies indicate Frailty Syndrome as a trigger for Cognitive decline.