Chinese Longitudinal Health Longevity Survey Research Articles

COPD and the risk of mild cognitive impairment and dementia: a cohort study based on the Chinese Longitudinal Health Longevity Survey.

BackgroundCOPD may lead to cognitive impairment or even dementia. However, the current conclusions are inconsistent with little evidence from prospective, large-sample studies. This study was designed to explore the association of COPD with mild cognitive impairment (MCI) and dementia risk based on a cohort study.Patients and methodsAll participants were from the Chinese Longitudinal Health Longevity Survey (CLHLS) 2011/2012 waves. The follow-up survey was conducted in 2014 and the incidence of MCI and dementia were recorded.ResultsDuring the 3-year follow-up period, 712 new cases of MCI and 83 new cases of dementia were diagnosed. The incidence of MCI and dementia were higher in those with COPD than those without COPD at baseline. Cox analysis showed that the HRs of COPD for MCI and dementia incidence were 1.486 (95% CI: 1.207–1.855) and 1.896 (95% CI: 1.079–3.330), respectively after adjusting for related covariates. For different baseline smoking status, those who were current smokers had the highest HRs of COPD for MCI and dementia.ConclusionBaseline COPD was independently associated with increased risk of MCI and dementia incidence among Chinese elderly, and the association was more pronounced among those who were current smokers.

Disability Transitions and Health Expectancies among Elderly People Aged 65 Years and Over in China: A Nationwide Longitudinal Study.

Disability has become a critical issue among elderly populations, yet limited large-scale research related to this issue has been conducted in China, an aging society. This study explored sex and urban-rural differences in disability transitions and life expectancies among older adults in China. Data were collected from the Chinese Longitudinal Health Longevity Survey (CLHLS), which enrolled people aged 65 and older and was conducted in randomly selected counties and cities across 22 provinces in China. Disability was diagnosed based on basic activities of daily living (BADLs) and instrumental activities of daily living (IADLs). Several individual characteristics were assessed, including sociodemographic factors (age, sex and region, etc.) and health behaviors (currently smoking, currently drinking, etc.). Multistate models were applied to analyze the transition rates among 4 states: no disability, mild disability, severe disability and death. The transition rates from disabled states to the no-disability state were found to decrease markedly with age. The rates of recovery from mild disability in rural areas were higher than those in urban areas. Rural elderly individuals lived shorter lives than their urban counterparts, but they tended to live with better functional status, spending a larger fraction of their remaining life with less severe disability. Based on these findings, devoting more attention and resources to rural areas may help less severely disabled people recuperate and prevent severe disability. The study provides insights into health plan strategies to help guide the allocation of limited resources.

Impact of the disability trajectory on the mortality risk of older adults in China

Using data from the Chinese Longitudinal Health Longevity Survey of 2005, 2008 and 2011, the authors compared the difference in the disability trajectory (DT) of survivor, decedent and dropped-out survey respondents and examined gender differences in DT using a group-based trajectory model, gender differences in the impact of DT on mortality risk (MR) among older adults, and mediating effects of resources and health status during late life through survival analysis. This analysis shows that the DTs of the survivors, decedents and dropped-out respondents differ remarkably. The trajectories of the decedents generally begin higher and increase more rapidly. Three types of DT exist for both genders: Type 1, the “independent type”; Type 2, the “low start, rapidly increasing in late life type”; and Type 3, the “high start, rapid development type”. Women are more likely to experience a DT of functional impairment. Men who experience the Type 3 trajectory suffer the highest MR, followed by those of the Type 1 and Type 2 trajectories. Women who experience the Type 3 trajectory suffer the highest MR, followed by those of the Type 2 and Type 1 trajectories. In addition, economic status, medical treatment, daily care by the family and chronic diseases mediate the impact of DT on MR for both genders, while the mediating effect of emotional support from children was only observed for women.

Re-Examining the Role of Engaging in Activities: Does its Effect on Mortality Change by Age among the Chinese Elderly?

Engaging in activities has been found beneficial overall to individuals’ well-being. What has not been systemically tested with large sample data is whether such benefits diminish at very old ages. This study uses the Chinese Longitudinal Health Longevity Survey (CLHLS) between 2002 and 2008 to test how the effect of engaging in activities on mortality changes by age among the elderly. Approximately half of the 16,064 people aged 65 and over interviewed in 2002 died within the following six-years. Two types of activities are examined: customary physical activities, such as such as doing housework and gardening, and social activities, such as playing cards and attending organized activities. The Cox model is applied to analyze the hazards of mortality. Both physical and social activities are found to reduce the hazards of mortality for the whole sample and both activities showed a negative interaction effect with age. As age increases, their beneficial effects decrease. These patterns are also evident in the sub-sample analysis by age and gender. Although many studies have shown the beneficial effect of engaging in activities for individuals’ well-being, as is well reported in the media, these results suggest a diminishing effect at old ages.

Association between serum albumin and cognitive performance in elderly Chinese

Objective: To explore association between serum albumin level and cognitive performance in elderly Chinese. Methods: All the subjects aged ≥65 years in the 8 longevity areas in Chinese longitudinal health longevity survey (CLHLS) were invited to participate the biomedical indepth CLHLS study, information about subjects' demographic characteristics, lifestyle, prevalence of diseases and health status was collected through household-interview. The cognitive performance was assessed with Mini Mental State Evaluation (MMSE) scale. Health examination was conducted by medical personnel and fasting venous blood samples were collected to detect the levels of triglycerides, total cholesterol, fasting glucose, creatine and blood albumin. MMSE score was compared and the trend was analyzed with generalized linear model. Association between albumin concentration and cognitive impairment was analyzed by logistic regression model. Results: Generalized linear model showed that adjusted MMSE score increased from 23.22 in the lowest quartile group to 25.07 in the highest quartile group (P for linear trend <0.001). Logistic regression analysis results showed that the higher albumin level was associated with the lower risk of cognitive impairment (P< 0.001), the OR decreased linearly with the increasing level of albumin (P<0.01), with the OR (95%CI) for the lower, higher and highest quartile groups was 0.64(0.45-0.91), 0.60(0.40-0.89) and 0.43(0.27-0.69), respectively, compared with the lowest quartile group. Conclusion: High level of serum albumin was associated with low risk of cognitive impairment.

Self-Rated Health, Interviewer-Rated Health, and Their Predictive Powers on Mortality in Old Age.

This study examines the potential use of interviewer-rated health (IRH) as a complementary measure of self-rated health (SRH) through a systematic comparison of their components and mortality-predictive powers in the Chinese elderly population. This study used a nationwide dataset with more than 12,000 adults aged 65 or older drawn from the 2005 and 2008 waves of the Chinese Longitudinal Health Longevity Survey (CLHLS). Disability, cognitive function, chronic disease conditions, psychological well-being, and health behaviors influenced both the SRH and IRH of Chinese older adults; these factors, especially disabilities, explained a large portion of the association between SRH and mortality. However, the impact of these factors on the association between IRH and mortality was limited. Furthermore, when both SRH and IRH were included in the analytical models, the association between SRH and mortality disappeared, while the association between IRH and mortality still persisted. Although there is some difference between IRH and SRH, IRH captures similar health information as SRH and is strongly predictive of mortality independent of SRH; thus, IRH could be a good supplementary measurement for well-adopted SRH.

Trajectory of physical health, cognitive status, and psychological well-being among Chinese elderly

This study investigates the trajectory of various dimensions of health status among the Chinese elderly in their late years. We used growth-curve analyses on a subsample (n≈2000) of the elderly from the Chinese Longitudinal Health Longevity Survey (CLHLS) who had longitudinal information from 1998 to 2005. Analyses controlled for a large set of individual and family characteristics. Our findings indicate that elderly who had relatively advantaged childhood socioeconomic status (SES) and who regularly engaged in physical and/or leisure activities had significantly healthier well-being than their respective counterparts on all dimensions considered. In addition, regularly participating in physical and/or leisure activities was associated with slow deterioration of health well-being among the Chinese elderly. The results indicate the potential benefits of engaging in physical and/or leisure activities, and consequently, the importance of implementing programs that promote such activities among elders in China.

Chinese Older Adults Taking Care of Grandchildren: Practices and Policies for Productive Aging

Older adults around the world provide care and support for their family, relatives, and friends. This not only generates immense economic and social value, but is also an important aspect of productive aging. This paper analyzes data from the 2005 Chinese Longitudinal Health Longevity Survey (CLHLS), the 2008 Chinese Residents’ Time Use Survey, and a study conducted by the author (Sun Popul J 4:14–18, 2006). In rural China, because the young labor force works in cities, a large number of “left-behind children” live with their grandparents. Such cross-generational families made up over a quarter of rural households in 2005. In the cross-generational family, the role and value of caregiving for grandchildren by elderly grandparents has been strengthened, as has the burden of care placed upon them. Based on an analysis of the policies and practices of productive aging, this paper seeks to raise awareness of the enormous caregiving contributions made by older adults. Collecting information on older adult caregiving will help inform a policy framework to provide professional and systematic support, so that family and social care systems can operate effectively.

Sleeping at the Century Mark

Sleeping at the Century Mark

Air Pollution, Economic Development of Communities, and Health Status Among the Elderly in Urban China

In Western societies, the impact of air pollution on residents' health is higher in less wealthy communities. However, it is not clear whether such an interaction effect applies to developing countries. The authors examine how the level of community development modifies the impact of air pollution on health outcomes of the Chinese elderly using data from the third wave of the Chinese Longitudinal Health Longevity Survey in 2002, which includes 7,358 elderly residents aged 65 or more years from 735 districts in 171 cities. The results show that, compared with a 1-point increase in the air pollution index in urban areas with a low gross domestic product, a similar increase in the air pollution index in areas with a high gross domestic product is associated with more difficulties in activities of daily living (odds ratio = 1.41, 95% confidence interval (CI): 1.09, 1.83), instrumental activities of daily living (linear coefficient = 0.98, 95% CI: 0.58, 1.37), and cognitive function (linear coefficient = 2.67, 95% CI: 1.97, 3.36), as well as a higher level of self-rated poor health (odds ratio = 2.20, 95% CI: 1.68, 2.86). Contrary to what has been found in the West, Chinese elderly who live in more developed urban areas are more susceptible to the effect of air pollution than are their counterparts living in less developed areas.