Associations of environmental factors with elderly health and mortality in China

Perception matters: How air pollution influences life satisfaction in China

Academic studies on environmental pollution have convincingly acknowledged the salient relevance of ambient pollutant emissions on individual life satisfaction. However, an understanding of how the different dimensions of air pollution influence public self-assessment of their living condition is required. This research investigates whether objective pollutant emissions and subjective evaluation influence individual life satisfaction. The findings were based on data from the China Environment Yearbook and China Social Survey in 2019. The multi-level linear regression model found that air pollutants emissions, including particulate matter (PM) and sulfur dioxide (SO2), failed to explain the variations in public life satisfaction because of the lag effect of public perception. A significant nexus between perceived air pollution and public life satisfaction was observed at a significance level of 0.01. Specially, as the perceived air pollution by the public increased by one-point, life satisfaction decreased by 0.22 on a scale of 1-10, on average. Heterogeneous analysis based on income further suggested the salient negative effect of PM emissions on life satisfaction only occurred in the high-income group. The findings were robust after various methodological analyses. This study has theoretical implications for understanding the effects of air pollution on public subjective perception and provides guidance for how the government can manage the relationship between environmental governance and life satisfaction.

Air pollution and the burden of long-term care: Evidence from China

We examine the causal effects of PM2.5 exposure on the burden of long-term care (LTC) by matching a satellite-based PM2.5 (particulate matter smaller than 2.5 micrometers (μm) in diameter) dataset with a nationally representative longitudinal study in China from 2011 to 2018. We find significant adverse effects of PM2.5 exposure-instrumented by thermal inversions-on the LTC burden. A 10 μg/m3 increase in annual PM2.5 exposure increases average monthly hours of LTC and the associated financial costs by 28 h and CNY 452, respectively. The effects are greater for those who had never smoked nor experienced severe PM2.5 pollution (annual average PM2.5 > 35 μg/m3) in the previous 5 years. We also find that as PM2.5 increases, chronic diseases, particularly cardiovascular diseases, could lead to a higher likelihood of LTC dependency but reduce the total hours and costs of LTC provision. Finally, we find that PM2.5 reduces the total years of LTC need, suggesting that PM2.5 increases LTC costs by increasing the severity of LTC dependency, rather than the duration of LTC need. Our findings can assist policymakers in planning for LTC provisions and clean air policies.

Does the community service environment affect the willingness of older adults people to socialize for older adults care?

Population ageing is a significant trend in social development and will remain a fundamental national condition in China for the foreseeable future. Socialized older adults care has become a crucial strategy for China to address population ageing. However, the current levels of acceptance and willingness to seek socialized older adults care among older adults are relatively low. This study focuses on examining how the community environment and services influence older adults people's willingness to engage in social activities related to older adults care. Using data from the China Longitudinal Ageing Social Survey (CLASS) (N = 9,657), this study investigated the impact of the community service environment on older adults people's willingness to participate in social activities related to older adults care through a logit model. The study revealed that 9.15% of older adults (N = 9,657) in China are willing to engage in social activities related to older adults care. Furthermore, the individual characteristics and family support of older adults play a significant role in shaping their willingness to engage in older adults care. The provision of medical services, daily care services, and entertainment venues by the community positively influence older adults people's willingness to participate in social activities related to older adults care (p < 0.01), whereas psychological counselling services have a negative impact (p < 0.01). The impact of community services on older adults people's willingness to engage in social activities related to older adults care varies due to factors such as smoking and chronic diseases. These findings provide valuable insights for improving older adults' social engagement in China.

Environmental Temperature, Other Climatic Variables, and Cardiometabolic Profile in Acute Myocardial Infarction

Objectives: To evaluate CV profiles, periprocedural complications, and in-hospital mortality in acute myocardial infarction (AMI) according to climate. Methods: Data from 2478 AMI patients (1779 men; mean age 67 ∓ 13 years; Pasquinucci Hospital ICU, Massa, Italy; 2007-2018) were retrospectively analyzed according to climate (LAMMA Consortium; Firenze, Italy) by using three approaches as follows: (1) annual warm (May-October) and cold (November-April) periods; (2) warm and cold extremes of the two periods; and (3) warm and cold extremes for each month of the two periods. Results: All approaches highlighted a higher percentage of AMI hospitalization for patients with adverse CV profiles in relation to low temperatures, or higher periprocedural complications and in-hospital deaths. In warmer times of the cold periods, there were fewer admissions of dyslipidemic patients. During warm periods, progressive heat anomalies were characterized by more smoker (approaches 2 and 3) and young AMI patient (approach 3) admissions, whereas cooler times (approach 3) evidenced a reduced hospitalization of diabetic and dyslipidemic patients. No significant effects were observed for the heat index and light circulation. Conclusions: Although largely overlapping, different approaches identify patient subgroups with different CV risk factors at higher AMI admission risk and adverse short-term outcomes. These data retain potential implications regarding pathophysiological mechanisms of AMI and its prevention.

Cognitive performance and all-cause mortality in community dwellers of Amerindian ancestry living in rural Ecuador: A population-based, longitudinal prospective study

OBJECTIVE

There is limited information on mortality risk in individuals with cognitive impairment living in rural Latin America. In this study, we assess the association between cognitive impairment and all-cause mortality in adults of Amerindian ancestry living in rural Ecuador.

PATIENTS AND METHODS

Middle-aged and older adults enrolled in the population-based Three Villages Study cohort were followed prospectively in order to estimate mortality risk according to their baseline cognitive performance as determined by the Montreal Cognitive Assessment (MoCA). Results were adjusted for demographics, level of education, traditional cardiovascular risk factors, symptoms of depression, severe tooth loss, and oily fish intake (factors previously associated with mortality in the study population).

RESULTS

Analysis included 1022 individuals followed for an average of 7.8 ± 3.4 years. Mean MoCA score was 21.2 ± 5.4 points (median: 22 points), with 334 (32.7%) individuals showing cognitive impairment, as evidenced by a MoCA score ≤ 19 points (the cutoff for poor cognitive performance based on previous studies in the same population). A total of 150 (14.7%) individuals died during the follow-up. Crude mortality rate was 2.87 per 100 person-years (95% C.I.: 2.08 - 3.96). For individuals with normal cognition, the mortality rate was 1.21 (95% C.I.: 0.92 - 1.50) while for those with cognitive impairment the rate increased to 3.48 (95% C.I.: 2.73 - 4.23). A multivariate Cox-proportional hazards model, confirmed that individuals with cognitive impairment had a significantly higher mortality risk than those without cognitive impairment (HR: 1.52; 95% C.I.: 1.05 - 2.18).

CONCLUSIONS

Cognitive impairment is associated with mortality in the study population.

Particulate Matter in Human Elderly: Higher Susceptibility to Cognitive Decline and Age-Related Diseases

This review highlights the significant impact of air quality, specifically particulate matter (PM), on cognitive decline and age-related diseases in the elderly. Despite established links to other pathologies, such as respiratory and cardiovascular illnesses, there is a pressing need for increased attention to the association between air pollution and cognitive aging, given the rising prevalence of neurocognitive disorders. PM sources are from diverse origins, including industrial activities and combustion engines, categorized into PM10, PM2.5, and ultrafine PM (UFPM), and emphasized health risks from both outdoor and indoor exposure. Long-term PM exposure, notably PM2.5, has correlated with declines in cognitive function, with a specific vulnerability observed in women. Recently, extracellular vesicles (EVs) have been explored due to the interplay between them, PM exposure, and human aging, highlighting the crucial role of EVs, especially exosomes, in mediating the complex relationship between PM exposure and chronic diseases, particularly neurological disorders. To sum up, we have compiled the pieces of evidence that show the potential contribution of PM exposure to cognitive aging and the role of EVs in mediating PM-induced cognitive impairment, which presents a promising avenue for future research and development of therapeutic strategies. Finally, this review emphasizes the need for policy changes and increased public awareness to mitigate air pollution, especially among vulnerable populations such as the elderly.

The influence of environment and Earnings on Prolonged existence and human fertility: A Deeper Dive into Asia's environmentally vulnerable nations

This study inspects the impact of environmental deterioration and income on longevity and fertility in Asian countries, specifically the nations that are highly vulnerable to extreme weather. The study examines the data, covering two decades from 2000 to 2019. The empirical conclusions of the panel ARDL-PMG and the CS-ARDL econometric models indicate that environmental degradation leads to a decline in birth rate and life expectancy, while a rising income has a significant influence over longevity. However, increasing per capita income alone cannot solve the problem of population crisis in climatically susceptible countries. Therefore, the sample countries must prioritize climate action and formulate climate-resilient policies to add more years to the lives of their citizens. Similarly, for increasing childbirth the sample nations need to make peace with nature. The outcomes of this study are strong enough, as both the models support each other's findings, producing similar significant outcomes.

The impact of household wealth gap on individual's mental health

BACKGROUND

Improving the individual's mental health is important for sustainable economic and social development. Although some studies found that household wealth gap may affect individuals' mental health, few studies have clarified the causal relationship between household wealth gap between mental health in China. This study examines the impact of the household wealth gap on individuals' mental health using data from the 2012-2018 China Family Panel Survey.

METHODS

This study first used the two-way fixed effects model to investigate the impact of household wealth gap on individuals' mental health. Considering the endogeneity, the two-stage least square and propensity score matching were employed to examine the impact of household wealth inequality on individuals' mental health.

RESULTS

The results show that the household wealth gap has negative impact on individuals' mental health. A series of robustness tests support this conclusion. The results of heterogeneity analysis show that the impact of household wealth gap on mental health is more pronounced among middle-aged and elderly individuals, residents with lower education levels, and rural residents. The results of the mechanism analysis suggest that the household wealth gap may affect individuals' mental health by influencing the individual's health insurance investment and neighborhood relations. In addition, the household wealth gap not only significantly negatively affects individuals' mental health in the short term but also in the medium- to long-term.

CONCLUSION

These findings suggest that the government should take various measures to narrow the wealth inequality between families, which may effectively improve the mental health of residents.

Social determinants of health and disease in companion dogs: a cohort study from the Dog Aging Project

Exposure to social environmental adversity is associated with health and survival across many social species, including humans. However, little is known about how these health and mortality effects vary across the lifespan and may be differentially impacted by various components of the environment. Here, we leveraged a relatively new and powerful model for human aging, the companion dog, to investigate which components of the social environment are associated with dog health and how these associations vary across the lifespan. We drew on comprehensive survey data collected on 21,410 dogs from the Dog Aging Project and identified five factors that together explained 33.7% of the variation in a dog's social environment. Factors capturing financial and household adversity were associated with poorer health and lower physical mobility in companion dogs, while factors that captured social support, such as living with other dogs, were associated with better health when controlling for dog age and weight. Notably, the effects of each environmental component were not equal: the effect of social support was 5× stronger than financial factors. The strength of these associations depended on the age of the dog, including a stronger relationship between the owner's age and the dog's health in younger as compared to older dogs. Taken together, these findings suggest the importance of income, stability and owner's age on owner-reported health outcomes in companion dogs and point to potential behavioral and/or environmental modifiers that can be used to promote healthy aging across species.

Changes in Plant-based Dietary Quality and Subsequent Risk of Cognitive Impairment among Older Chinese Adults: A National Community-based Cohort Study

BACKGROUND

It is unclear how changes in plant-based dietary quality are linked to subsequent risk of cognitive impairment. This study aims to evaluate this relationship using data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS).

METHODS

A total of 6662 participants free of cognitive impairment in 2008 were included and followed up to 2018. Plant-based dietary quality was assessed by three indices: overall plant-based diet index (PDI), healthful plant-based diet index (hPDI), and unhealthful plant-based diet index (uPDI). Changes in plant-based diet quality from 2008 to 2011 were classified into quintiles. We assessed incident cognitive impairment (from 2011 to 2018) by using the Mini-Mental State Examination (MMSE). Cox proportional-hazards models were performed.

RESULTS

We recorded 1571 incident cases of cognitive impairment during a median of 10 years of follow-up. Compared with participants whose plant-based diet had no change or was relatively stable over three years, the full-adjusted hazard ratios (HRs) with 95% confidence intervals (CI) for cognitive impairment were 0.77 (0.64, 0.93), 0.72 (0.60, 0.86), and 1.50 (1.27, 1.77) among participants with a large increase in PDI, hPDI, and uPDI, respectively. The HRs with 95% CI were 1.22 (1.02, 1.44), 1.30 (1.11, 1.54), and 0.80 (0.67, 0.96) among participants with a large decrease in PDI, hPDI, and uPDI, respectively. Every 10-point increase in PDI and hPDI was associated with 26% and 30% lower risk of cognitive impairment, while every 10-point increase in uPDI was associated with 36% higher risk.

CONCLUSIONS

Older adults with increased adherence to an overall plant-based diet and a healthful plant-based diet over three years have a lower risk of cognitive impairment, while those with increased adherence to an unhealthy plant-based diet had a higher risk of cognitive impairment.

Impacts of health expenditures and environmental degradation on health status—Disability-adjusted life years and infant mortality

Introduction

Human health and well-being are intimately related to environmental quality. In this respect, the present study contributes to the existing health economic literature by examining whether public and private health expenditures (PPHE) moderate the incidences of environmental degradation on the health status in Saudi Arabia, particularly disability-adjusted life years (DALYs) and infant mortality.

Methods

Using the fully modified ordinary least squares (FMOLS) method.

Results and Discussion

The empirical results revealed that (i) unconditional positive impacts of CO2 emissions on increasing DALYs and infant mortality; (ii) conditional negative impacts of public health expenditures on DALYs and infant mortality in all the estimated models, whereas global and private expenditure contribute only on reducing infant mortality; (iii) public health expenditure is more effective than private health expenditure in reducing infant mortality; (iv) the effects of the interactions between the indicators of both health expenditures and CO2 emissions on DALYs and infant mortality are negative and significant only for the specifications relating to public health expenditures, indicating that this later could be employed as a policy or conditional variable that moderates the adverse impacts of carbon emissions on the population’s health status. Generally, the study presents an overview of environmental health change’s effects and examine how these effects may be reduced through increasing health spending. The study provides recommendations for addressing health status, health expenditures, and carbon emissions, all of which are directly or indirectly linked to the study.

Exploring the relationship between air quality and health shocks to the elderly: A retrospective cross-sectional study in China

Methods

We selected 5,172 microdata on individuals from the China Health and Retirement Longitudinal Study (CHARLS) 2018. The binary logit model, the ordered logit model, and the stepwise regression were employed to compare the effects of air pollution on self-rated health (SRH) and activities of daily living (ADL) in an elderly population. The effects on health shocks were explored in different age groups, different gender groups, different regions and different sources of pollutants, respectively.

Results

We found that air pollution significantly increased the risk of health shocks in the elderly population, especially in the 60–69 year age group, and the eastern/central region, where NO2 and O3 were important pollutant sources.

Conclusion

Targeted management of the environment is necessary to improve the health status of China's elderly population. In addition, paying attention to the health status of vulnerable populations is needed to achieve social equity.

Association Between Internet Use and Physical Health, Mental Health, and Subjective Health in Middle-aged and Older Adults: Nationally Representative Cross-sectional Survey in China

BACKGROUND

Internet use is an important means of accessing health-related information. Identifying the associations between internet use and health outcomes could provide insight into strategies for improving public health among middle-aged and older adults (45 years and up).

OBJECTIVE

This study aimed to examine the relationship between internet use and health outcomes in middle-aged and older adults.

METHODS

Data were obtained from the 2018 China Health and Retirement Longitudinal Study. Physical, mental, and subjective health were assessed using the Activities of Daily Living (ADL) Scale, the 10-item Center for Epidemiologic Studies Depression Scale, and the 3-level Self-Rated Health Scale, respectively. The chi-square test and rank sum test were used to explore whether internet use was associated with health status. A multivariate logistic regression model was used to determine this association further after controlling for the confounding factors.

RESULTS

Overall, 13% (1752/13,474) of the participants used the internet. Regression analyses revealed that the prevalence of depression (odds ratio [OR] 0.59, 95% CI 0.52-0.68; P<.001), negative self-rated health (OR 0.68, 95% CI 0.61-0.76; P<.001), and difficulty with ADL (OR 0.48, 95% CI 0.39-0.60; P<.001) in the participating middle-aged and older adult was lower in those using the internet than nonusers. After controlling for confounding factors, internet use was found to be negatively associated with difficulty with ADL (urban: OR 0.44, 95% CI 0.32-0.61; P<.001 vs rural: OR 0.55, 95% CI 0.41-0.75; P<.001), depression (urban: OR 0.69, 95% CI 0.57-0.84; P<.001 vs rural: OR 0.52, 95% CI: 0.43-0.63; P<.001), and self-rated health status (urban: OR 0.70, 95% CI 0.61-0.81; P<.001 vs rural: OR 0.67, 95% CI 0.57-0.78; P<.001) among middle-aged and older adults in both urban and rural areas.

CONCLUSIONS

Internet use had a positive effect on the physical and mental health of middle-aged and older adults who participated in this study. However, the internet usage rate remains low among older Chinese people. Therefore, the internet penetration rate should be a priority.

A Longitudinal Analysis of the Association Between Long-Term Exposure to Air Pollution and Cognitive Function Among Adults Aged 45 and Older in China

OBJECTIVES

Evidence suggests long-term exposure to fine particulate matter air pollution (PM2.5) is associated with a higher risk of cognitive impairment, especially among older adults. This study examines the relationship between PM2.5 exposure and cognitive function in China's aging population.

METHODS

We used longitudinal data from the China Health and Retirement Longitudinal Study (2011-2015) linked with historical PM2.5 concentrations (2000-2015) from remotely sensed satellite data. Growth curve models were applied to estimate associations between PM2.5 exposure (measured in intensity, duration, and a joint variable of intensity with duration for cumulative exposure) and cognitive function.

RESULTS

Relative to the lowest exposure group, exposure in the second group of PM2.5 intensity (35-50 μg/m3) is associated with poorer cognitive function, but higher levels of PM2.5 appear to be associated with better cognitive function, indicating a U-shaped association. Similar patterns are seen for fully adjusted models of PM2.5 duration: the second group (13-60 months) is associated with worse cognitive function than the first group (0-12 months), but coefficients are nonsignificant in longer duration groups. Joint analysis of PM2.5 intensity with duration suggests that duration may play a more detrimental role in cognitive function than intensity. However, we do not find a statistically significant association between PM2.5 exposure and the rate of cognitive decline.

DISCUSSION

Our findings are mixed and suggest that some categories of higher and longer exposure to PM2.5 are associated with poorer cognitive function, while that exposures do not hasten cognitive decline. However, more work is necessary to disentangle PM2.5 exposure from individuals' background characteristics, particularly those jointly associated with cognitive function and urban living.

High social risk and mortality. A prospective study in community-dwelling older adults living in a rural Ecuadorian village

High social risk has been associated with mortality, but information on this relationship in remote rural communities is limited. Using the social determinants of health (SDH) specified in the Gijon's social-familial evaluation scale (SFES), we aimed to assess mortality risk according to levels of social risk in community-dwelling older adults living in rural Ecuador. Following a longitudinal population-based design, this study prospectively followed 457 individuals for an average of 8.2 ± 2.6 years. A total of 115 (25.2 %) individuals died during the study years. The mean Gijon's SFES score was 9.4 ± 2.8 points among survivors versus 12.3 ± 4 points among those who died (p < 0.001). Separate models using individual SDH components as exposures showed that deficits in family situation, social relationships and support networks were significantly associated with mortality, whereas economic status and housing factors were not. A Cox-proportional hazard model, with the Gijon's SFES score stratified in tertiles, showed a more than 5-fold increase in mortality among individuals in the third tertile compared with those in first and second tertiles, after adjusting for relevant covariates (HR: 5.36; 95 % C.I.: 3.09 - 9.32). Study results indicate an important contribution of high social risk to mortality, and may help to identify potential interventional targets that are focused on encouraging social interactions, and that may reduce mortality in older adults living in remote settings.

The role of residential greenness levels, green land cover types and diversity in overweight/obesity among older adults: A cohort study

BACKGROUND

Few studies have investigated the effects of greenness exposure, green land cover types and diversity and their interaction with particulate matter (PM) to adiposity.

METHOD

Cohort data were collected from the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Baseline data on greenness levels, green land cover types and diversity were assessed by the Normalized Difference Vegetation Index (NDVI), three greenery types (trees, shrublands and grassland) and Shannon's diversity index, respectively. Body mass index (BMI) and waist circumference (WC) were separately used as dependent variables and represented for peripheral overweight/obesity and central obesity, respectively. The mixed Cox model with random intercept was used to estimate the effects of greenness levels, types and diversity on overweight/obesity using single and multiple exposure models. We also examined the interaction of PM and the aforementioned indicators on overweight/obesity on both additive and multiplicative scales.

RESULTS

Single exposure models showed that higher levels of residential greenness, tree coverage and ratio of trees to shrublands/grassland were inversely associated with peripheral overweight/obesity and central obesity. An increase in shrublands, grassland and diversity of green was related to lower odds of peripheral overweight/obesity. Multiple exposure models confirmed the association between greenness levels and peripheral overweight/obesity. Males, educated participants and elderly who lived in southern regions and areas with cleaner air environments acquired more benefits from greenspace exposure. Single and multiple exposure models indicated that an antagonistic effect of increasing PM and decreasing greenness levels on peripheral overweight/obesity and central obesity. Single exposure models showed the potential interaction of tree coverage, ratio of trees to grassland and PM_2.5 exposures on the risk of peripheral overweight/obesity.

CONCLUSION

Increasing residential greenness and diversity of green were associated with healthy weight status. The relationship between greenery and overweight/obesity varied, and the effects of greenspace exposure on overweight/obesity were associated with air pollution.

Associations between Frailty and Ambient Temperature in Winter: Findings from a Population-Based Study

Frailty is an accumulation of deficits characterized by reduced resistance to stressors and increased vulnerability to adverse outcomes. However, there is little known about the effect of ambient temperature in winter on frailty among older adults, a population segment with the highest frailty prevalence. Thus, the objective of this study is to investigate the associations between frailty and ambient temperature in winter among older adults. This study was based on the Chinese Longitudinal Healthy Longevity Survey (CLHLS) of older adults aged ≥65 years from the 2005, 2008, 2011, and 2014 waves. The 39-item accumulation of frailty index (FI) was used to assess the frailty status of the participants. The FI was categorized into three groups as follows: robust (FI ≤ 0.10), prefrail (FI > 0.10 to <0.25), and frail (FI ≥ 0.25). Generalized linear mixed models (GLMMs) were conducted to explore the associations between frailty and ambient temperature in winter. A generalized estimating equation (GEE) modification was applied in the sensitivity analysis. A total of 9421 participants were included with a mean age of 82.81 (SD: 11.32) years. Compared with respondents living in the highest quartile (≥7.5 °C) of average temperature in January, those in the lowest quartile (<−1.9 °C) had higher odds of prefrailty (OR = 1.35, 95% CI 1.17−1.57) and frailty (OR = 1.61, 95%CI 1.32−1.95). The associations were stronger among the low-education groups, agricultural workers before retirement, and non-current exercisers. Additionally, results from the GEE model reported consistent findings. Lower levels of ambient temperature in winter were associated with higher likelihoods of prefrailty and frailty. The findings on vulnerability characteristics could help improve public health practices to tailor cold temperature health education and warning information.

Associations of PM2.5 intensity and duration with cognitive impairment: A longitudinal analysis of middle-aged and older adults in China

Long-term exposure to air pollution is associated with a higher risk of cognitive impairment; however, the understanding of this association is incomplete. We aimed to explore the relationship between fine particulate matter (PM_2.5) exposure and cognitive function using a prospective cohort of ageing adults, including 19,389 respondents in four waves of the China Health and Retirement Longitudinal Study (CHARLS, 2011-2018) linked with the historical PM_2.5 concentrations (2000-2018) in China. By extending the measurement of PM_2.5 exposure from exposure intensity (averaged PM_2.5 concentrations) to exposure duration (the number of months with higher PM_2.5 concentrations), we employed two linear models, the fixed-effect and mixed-effect linear models, to estimate the associations between PM_2.5 exposure and cognitive impairment, with adjustments for individual and regional covariates. Our findings show that the higher PM_2.5 intensity was associated with worse cognitive function, but the associations were only statistically significant in a longer exposure period (more than one year), especially in the 10-year exposure (Coefficient: -0.13; 95% Confidence Interval: -0.22, -0.04). Similar patterns were seen for fully adjusted models of PM_2.5 duration: a longer duration in PM_2.5 exposure was associated with lower cognitive scores, and the duration with higher cut-off points had stronger effects on cognitive function except for the duration at 75 μg/m³, suggesting a possible coincidence of increasing air pollution and economic development. The stronger exposure to PM_2.5 was associated with poorer cognitive function among Chinese adults, while more work is necessary to explore the causal effect of air pollution, independent of individual and contextual background characteristics.

Associations between household solid fuel use and activities of daily living trajectories: A nationwide longitudinal study of middle and older adults in China

BACKGROUND

More studies focus on reporting the effects of ambient air pollution on physical activity while ignoring the hazards of indoor air pollution caused by household solid fuel use. Moreover, the impact of individual cognitive and depressive status on the health effects of air pollution is often overlooked.

OBJECTIVE

We examined the association between household solid fuel and activities of daily living (ADL) trajectories, and further examined this association in homogeneous subgroups of cognitive or depressive trajectories.

METHODS

Participants were from the China Health and Retirement Longitudinal Study, which conducted four waves of surveys from 2011 to 2018. We collected information on participants' household fuel use, then the ADL, cognitive and depressive performances were assessed in each wave. The latent growth mixture model (LGMM) was used to identify the optimal trajectory class for ADL, cognition, and depression. Then, the multinomial logistic regression was used to assess the association between solid fuel use and ADL trajectories in total population, as well as subgroups with different cognitive or depression trajectories. Furthermore, we examined the association between switching household fuel types and ADL trajectories across the four-wave survey.

RESULTS

The study sample included 7052 participants. We identified three ADL trajectory classes in total population: "Low-stable", "Moderate-anterior rise", and "Moderate-posterior rise". The multinomial logistic regression results showed that solid fuel use was associated with elevated odds for the adverse ADL trajectories, and this association was still shown in homogeneous subgroups of cognitive or depressive trajectories, while some effects were less significant. In addition, the risk of adverse ADL trajectories generally increases with the times of solid fuel use across the four-wave survey.

CONCLUSIONS

For middle and older adults in China, household solid fuel use was not conducive to physical activity development, which inspires that a further transformation to cleaner fuels is an important intervention.

Associations among drinking water quality, dyslipidemia, and cognitive function for older adults in China: evidence from CHARLS

BACKGROUND

The current study aimed to examine the association between drinking water quality and cognitive function and to identify the direct and indirect effects of drinking water quality and dyslipidemia on cognitive function among older adults in China.

METHODS

Primary data for the study were selected from China Health and Retirement Longitudinal Study (CHARLS, 2015) and 4,951 respondents aged 60 and above were included. Data on drinking water quality were selected from the 2015 prefectural water quality data from the Institute of Public and Environment Affairs in China and measured by the Blue City Water Quality Index. Dyslipidemia was measured by self-reported dyslipidemia diagnosis and lipid panel. Three composite measures of cognitive function included mental status, episodic memory, and global cognition. Mixed effects models were conducted to assess the associations between drinking water quality or dyslipidemia and cognitive function. The mediation effects of dyslipidemia were examined by path analyses.

RESULTS

Exposure to high quality drinking water was significantly associated with higher scores in mental status, episodic memory, and global cognition (β = 0.34, p < 0.001 for mental status; β = 0.24, p < 0.05 for episodic memory; β = 0.58, p < 0.01 for global cognition). Respondents who reported dyslipidemia diagnosis had higher scores in the three composite measures of cognitive function (β = 0.39, p < 0.001 for mental status; β = 0.27 p < 0.05 for episodic memory; β = 0.66, p < 0.001 for global cognition). An elevated blood triglycerides was only associated with higher scores in mental status (β = 0.21, p < 0.05). Self-reported dyslipidemia diagnosis was a suppressor, which increased the magnitude of the direct effect of drinking water quality on mental status, episodic memory, and global cognition.

CONCLUSION

Drinking water quality was associated with cognitive function in older Chinese and the relationship was independent of natural or socioeconomic variations in neighborhood environments. Improving drinking water quality could be a potential public health effort to delay the onset of cognitive impairment and prevent the dementia pandemic in older people.

Plant-based dietary patterns and cognitive function: A prospective cohort analysis of elderly individuals in China (2008-2018)

INTRODUCTION

Plant-based diets confer health benefits, especially on the prevention of noncommunicable diseases. The relationship between plant-based dietary patterns on cognitive function as a neurological outcome needs more evidence. We aimed to assess the associations between plant-based dietary patterns and cognitive function among Chinese older adults.

METHODS

We used four waves (2008-2018) of the Chinese Longitudinal Healthy Longevity Survey. We included 6136 participants aged 65 years and older with normal cognition at baseline. We constructed an overall plant-based diet index (PDI), healthful plant-based diet index (hPDI), and unhealthful plant-based diet index (uPDI) from questionnaires. We used the Mini-Mental State Examination (MMSE) to assess cognitive function. We used the multivariable-adjusted generalized estimating equation to explore the corresponding associations.

RESULTS

The multivariable-adjusted models showed inverse associations between plant-based dietary patterns and cognitive function. The highest quartiles of PDI and hPDI were associated with a 55% (odds ratio [OR] = 0.45, 95% CI: 0.39, 0.52) decrease and a 39% (OR = 0.61, 95% CI: 0.54, 0.70) decrease in the odds of cognitive impairment (MMSE < 24), compared with the lowest quartile. In contrast, the highest quartile of uPDI was associated with an increased risk (OR = 2.03, 95% CI: 1.79, 2.31) of cognitive impairment. We did not observe pronounced differences by selected socioeconomic status, physical activity, residential greenness, and APOE ε4 status.

CONCLUSIONS

Our findings suggested that adherence to healthy plant-based dietary patterns was associated with lower risks of cognitive impairment among older adults, and unhealthy plant-based dietary patterns were related to higher risks of cognitive impairment.

The superposition effects of air pollution on government health expenditure in China- spatial evidence from GeoDetector

Background

As the fifth-largest global mortality risk factor, air pollution has caused nearly one-tenth of the world’s deaths, with a death toll of 5 million. 21% of China’s disease burden was related to environmental pollution, which is 8% higher than the US. Air pollution will increase the demand and utilisation of Chinese residents’ health services, thereby placing a greater economic burden on the government. This study reveals the spatial impact of socioeconomic, health, policy and population factors combined with environmental factors on government health expenditure.

Methods

Spearman’s correlation coefficient and GeoDetector were used to identify the determinants of government health expenditure. The GeoDetector consist of four detectors: factor detection, interaction detection, risk detection, and ecological detection. One hundred sixty-nine prefecture-level cities in China are studied. The data sources are the 2017 data from China’s Economic and Social Big Data Research Platform and WorldPOP gridded population datasets.

Results

It is found that industrial sulfur dioxide attributed to government health expenditure, whose q value (explanatory power of X to Y) is 0.5283. The interaction between air pollution factors and other factors will increase the impact on government health expenditure, the interaction value (explanatory power of × 1∩× 2 to Y) of GDP and industrial sulfur dioxide the largest, whose values is 0.9593. There are 96 simple high-risk areas in these 169 areas, but there are still high-risk areas affected by multiple factors.

Conclusion

First, multiple factors influence the spatial heterogeneity of government health expenditure. Second, health and socio-economic factors are still the dominant factors leading to increased government health expenditure. Third, air pollution does have an important impact on government health expenditure. As a catalytic factor, combining with other factors, it will strengthen their impact on government health expenditure. Finally, an integrated approach should be adopted to synergisticly governance the high-risk areas with multi-risk factors.

The effects of greenness exposure on hypertension incidence among Chinese oldest-old: a prospective cohort study

BACKGROUND

Although the oldest-old (those aged over 80 years) are vulnerable to environmental factors and have the highest prevalence of hypertension, studies focusing on greenness exposure and the development of hypertension among them are insufficient. The aim of this study was to explore the association between residential greenness and hypertension in the oldest-old population.

METHODS

This cohort study included data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS). The oldest-old were free of hypertension at baseline (2008), and hypertension events were assessed by follow-up surveys in 2011, 2014, and 2018. The one-year averages of the normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI) at 500-m buffer before the interview year of incident hypertension or last censoring interview were collected at the level of 652 residential units (district or county). The linear or nonlinear association between greenness and hypertension incidence was analyzed using the Cox proportional hazards model with penalized splines. The linear links between greenness and hypertension incidence were determined using the Cox proportional hazards model included a random effect term.

RESULTS

Among 5253 participants, the incidence rate of hypertension was 7.25 (95% confidence interval [CI]: 6.83-7.67) per 100 person-years. We found a nonlinear association between greenness exposure and hypertension risk, and the exposure-response curve showed that 1 change point existed. We examined the linear effect of greenness on hypertension by categorizing the NDVI/EVI into low and high-level exposure areas according to the change point. We found more notable protective effects of each 0.1-unit increase in greenness on hypertension incidence for participants living in the high-level greenness areas (hazard ratio (HR) = 0.60; 95% CI: 0.53-0.70 for NDVI; HR = 0.46; 95% CI: 0.37-0.57 for EVI). In contrast, no significant influence of greenness exposure on hypertension risk was found for participants living in the low-level greenness areas (HR = 0.77; 95% CI: 0.38-1.55 for NDVI; HR = 0.73; 95% CI: 0.33-1.63 for EVI).

CONCLUSIONS

Greenness exposure is nonlinearly associated with hypertension risk among the oldest-old, presenting its relationship in an inverse "U-shaped" curve. Greenness is a protective factor that decreases the risk of hypertension.

Green Space, Air Pollution, Weather, and Cognitive Function in Middle and Old Age in China

Prior research has shown that environmental hazards, such as limited green space, air pollution, and harmful weather, have the strong adverse impact on older adults' cognitive function; however, most of the studies were conducted in developed countries and limited to cross-sectional analyses. China has the largest aging population in the world so the research evidence from it can offer an insight to the study in other developing countries facing similar issues and inform future public health policy and disease control. This study examined the long-term impact of environmental factors, namely, green space coverage, air pollution, and weather conditions on cognitive function using a nationally representative sample consisting of adults aged 45 years and older selected from the China Health and Retirement Longitudinal Study (CHARLS 2011–2018), the China City Statistical Yearbook, and other sources. Multilevel growth curve models were utilized for analysis and the mediator effects of physical activity and social engagement on the relationship between environmental factors and cognitive function were examined. Findings of this study showed that after controlling for sociodemographic characteristics, annual precipitation of 80 cm or more, living in areas with July temperature of 28°C or higher, urban community, and green space coverage were positively associated with cognition score at the baseline and lower precipitation, urban community, and greater green space coverage were associated with slower cognitive decline over a 7-year period. The impact of gross domestic product (GDP) seemed to take into effect more and more over time. These effects did not substantially change after weekly total hours of physical activities and levels of social engagement were added. More research on the mechanisms of the effect of environmental factors on cognition is needed such as the subgroup analyses and/or with more aspects of environmental measures.

Climatic influences on cardiovascular diseases

Classical risk factors only partially account for variations in cardiovascular disease incidence; therefore, also other so far unknown features, among which meteorological factors, may influence heart diseases (mainly coronary heart diseases, but also heart failure, arrhythmias, aortic dissection and stroke) rates. The most studied phenomenon is ambient temperature. The relation between mortality, as well as cardiovascular diseases incidence, and temperature appears graphically as a ‘‘U’’ shape. Exposure to cold, heat and heat waves is associated with an increased risk of acute coronary syndromes. Other climatic variables, such as humidity, atmospheric pressure, sunlight hours, wind strength and direction and rain/snow precipitations have been hypothesized as related to fatal and non-fatal cardiovascular diseases incidence. Main limitation of these studies is the unavailability of data on individual exposure to weather parameters. Effects of weather may vary depending on other factors, such as population disease profile and age structure. Climatic stress may increase direct and indirect risks to human health via different, complex pathophysiological pathways and exogenous and endogenous mechanisms. These data have attracted growing interest because of the recent earth’s climate change, with consequent increasing ambient temperatures and climatic fluctuations. This review evaluates the evidence base for cardiac health consequences of climate conditions, and it also explores potential further implications.

Perceived Environmental Attributes: Their Impact on Older Adults' Mental Health in Malaysia

In Malaysia, the population of older adults will increase in the coming years. In this context, there is a requirement to build an age-friendly environment to enable the elderly to age healthily. Many studies have shown that a built environment that allows older adults to age in place improves their mental health. However, person-environment analysis that considers mental well-being has remained rare for older adults living in Malaysia. This study examines the relationship between Malaysian seniors’ perceptions of their surroundings at home and in the neighborhood and their mental health. Using stratified sampling, 510 seniors aged 60 and over were interviewed. The results showed that accessibility (p-value 0.033, 95% CI for coefficients 0.006, 0.146), environmental qualities (0.015, 0.014, 0.129) and neighborhood problems (0.000, −0.299, −0.146) were significant determinants of elderly people’s mental health. With respect to respondents’ socio-demographic characteristics, female elderly (0.000, 0.616, 0.782), older adults with an elementary education (0.000, 0.263, 0.685) or a college degree (0.026, 0.019, 0.294), being married (0.005, 0.047, 0.259), the ability to drive (0.000, 0.993, 1.315), the number of dependents in the family (0.003, −0.060, −0.012), and homeownership (0.000, −0.602, −0.271) were significantly related to mental well-being.

Effect of Environmental Planning on Elderly Individual Quality of Life in Severe Cold Regions: A Case Study in Northeastern China

With the development of urbanization and the ageing population, the improvement of the urban environment and the quality of life (QOL) of the elderly in cities with a cold climate have become critical issues to be addressed. However, only a few studies have focused on this aspect. According to a review of the literature, the contents of the built environment (BE) in severe cold regions are defined as thirteen key factors of four categories (density, environmental aesthetics, outdoor environment, and accessibility) and the QOL of old people consists of three aspects (residential, health, and social satisfaction). This study explores how BE variables are associated with the QOL of older adults by using ordered logit and gologit2 models. The data consist of the results of 1945 questionnaires from field surveys in 11 different residential areas, across two cities in northeastern China. The results show: (1) Walkability in winter, distance to a public park of 400–1000 m, outdoor shelters and seating, less than five buses available, and a mixture of evergreen and deciduous trees are five of the most important variables of BE that have a significant positive impact on QOL compared with other climatic regions; (2) “Pocket parks” and pedestrian walkway safety are appropriate approaches to improve wellbeing under local economic conditions. For public transportation, metro and rail transit systems are encouraged, and some rules are needed to reduce the number of buses in harsh weather conditions; (3) Compared with spatial distribution in other climates, the scope of a 15 min city should be less than 1km in severe cold areas. From the findings, we conclude that there are six possible pattern languages to improve the urban environment, and they can provide information for further study on environmental planning in severe cold regions.

Interaction between plant-based dietary pattern and air pollution on cognitive function: a prospective cohort analysis of Chinese older adults

BACKGROUND

Air pollution is a risk factor for poor cognitive function, while a plant-based dietary pattern is associated with better cognitive function. We aimed to explore their interaction with cognitive function among older adults.

METHODS

We used a prospective cohort of old individuals, including 6525 participants of the Chinese Longitudinal Healthy Longevity Survey (CLHLS), aged 65-110 years and with normal cognition at baseline. Air pollution measurement was derived using satellite-derived annual average fine particulate matter (PM2.5) concentrations based on residential locations. Plant-based diet index (PDI) was calculated using survey responses to assess the dietary pattern. Repeated measures of the Mini-Mental State Examination (MMSE) were utilized to assess cognitive function. We applied the Cox proportional hazard regression to explore the associations and further stratified the analysis by PDI.

FINDINGS

During a median of 5·6-year follow-up, 1537 (23·6%) out of 6525 participants with normal cognition at baseline developed poor cognitive function (MMSE <18). Living in areas with the highest quintile of cumulative PM2.5 was associated with a 46% increase in the risk of developing poor cognitive function (hazard ratio (HR): 1·46, 95% confidence interval (CI): 1·20, 1·77), compared to those living in areas with the lowest quintile. We observed a significant interaction between cumulative PM2.5 and PDI (p-interaction: 0·04), with the corresponding associations of cumulative PM2.5 being more pronounced among participants with lower PDI (HR: 1·68, 95% CI: 1·26, 2·24) than those with higher PDI (HR: 1·28, 95% CI: 0·98, 1·68).

INTERPRETATION

Plant-based dietary pattern may attenuate detrimental impacts of PM2.5 on cognitive function among older adults. Adherence to the plant-based dietary pattern could be used to prevent adverse neurological effects caused by air pollution, especially in developing regions.

Role of brain extracellular vesicles in air pollution-related cognitive impairment and neurodegeneration

A relationship between environmental exposure to air pollution and cognitive impairment and neurological disorders has been described. Previous literature has focused on the direct effects of the air pollution components on neuronal and glial cells, as well as on involvement of oxidative stress and neuroinflammation on microglia and astrocyte reactivity. However, other mechanisms involved in the air pollution effects on central nervous system (CNS) toxicity can be playing critical roles. Increasingly, extracellular vesicle's (EVs) mediated intercellular communication is being recognized as impacting the development of cognitive impairment and neurological disorders like Alzheimer's disease and others. Here we describe the available evidence about toxic air pollutants and its components on brain, an involvement of brain cells specific and EVs types (based in the origin or in the size of EVs) in the initiation, exacerbation, and propagation of the neurotoxic effects (inflammation, neurodegeneration, and accumulation of neurotoxic proteins) induced by air pollution in the CNS. Additionally, we discuss the identification and isolation of neural-derived EVs from human plasma, the most common markers for neural-derived EVs, and their potential for use as diagnostic or therapeutic molecules for air pollution-related cognitive impairment and neurodegeneration.

The Association Between Long-Term Exposure to Particulate Matter and Incidence of Hypertension Among Chinese Elderly: A Retrospective Cohort Study

Background and Objectives: Studies that investigate the links between particulate matter ≤2. 5 μm (PM_2.5) and hypertension among the elderly population, especially those including aged over 80 years, are limited. Therefore, we aimed to examine the association between PM_2.5 exposure and the risk of hypertension incidence among Chinese elderly. Methods: This prospective cohort study used 2008, 2011, 2014, and 2018 wave data from a public database, the Chinese Longitudinal Healthy Longevity Survey, a national survey investigating the health of those aged over 65 years in China. We enrolled cohort participants who were free of hypertension at baseline (2008) from 706 counties (districts) and followed up in the 2011, 2014, and 2018 survey waves. The annual PM_2.5 concentration of 706 counties (districts) units was derived from the Atmospheric Composition Analysis Group database as the exposure variable, and exposure to PM_2.5 was defined as 1-year average of PM_2.5 concentration before hypertension event occurrence or last interview (only for censoring). A Cox proportional hazards model with penalized spline was used to examine the non-linear association between PM_2.5 concentration and hypertension risk. A random-effects Cox proportional hazards model was built to explore the relationship between each 1 μg/m³, 10 μg/m³ and quartile increment in PM_2.5 concentration and hypertension incidence after adjusting for confounding variables. The modification effects of the different characteristics of the respondents were also explored. Results: A total of 7,432 participants aged 65-116 years were enrolled at baseline. The median of PM_2.5 exposure concentration of all the participants was 52.7 (inter-quartile range, IQR = 29.1) μg/m³. Overall, the non-linear association between PM_2.5 and hypertension incidence risk indicated that there was no safe threshold for PM_2.5 exposure. The higher PM_2.5 exposure, the greater risk for hypertension incidence. Each 1 μg/m³ [adjusted hazard ratio (AHR): 1.01; 95% CI: 1.01-1.02] and 10 μg/m³ (AHR: 1.12; 95% CI: 1.09-1.16) increments in PM_2.5, were associated with the incidence of hypertension after adjusting for potential confounding variables. Compared to first quartile (Q1) exposure, the adjusted HRs of hypertension incidence for the Q2, Q3 and Q4 exposure of PM_2.5 were 1.31 (95% CI: 1.13-1.51), 1.35 (95% CI: 1.15-1.60), and 1.83 (95% CI: 1.53-2.17), respectively. The effects appear to be stronger among those without a pension, living in a rural setting, and located in central/western regions. Conclusion: We found no safe threshold for PM_2.5 exposure related to hypertension risk, and more rigorous approaches for PM_2.5 control were needed. The elderly without a pension, living in rural and setting in the central/western regions may be more vulnerable to the effects of PM_2.5 exposure.

Alzheimer's Disease: Pathogenesis and Therapeutic Interventions

BACKGROUND

Alzheimer's Disease (AD) is the most common cause of dementia. Genetics, excessive exposure to environmental pollutants, as well as unhealthy lifestyle practices are often linked to the development of AD. No therapeutic approach has achieved complete success in treating AD; however, early detection and management with appropriate drugs are key to improving prognosis.

INTERVENTIONS

The pathogenesis of AD was extensively discussed in order to understand the reasons for the interventions suggested. The interventions reviewed include the use of different therapeutic agents and approaches, gene therapy, adherence to healthy dietary plans (Mediterranean diet, Okinawan diet and MIND diet), as well as the use of medicinal plants. The potential of nanotechnology as a multidisciplinary and interdisciplinary approach in the design of nano-formulations of AD drugs and the use of Superparamagnetic Iron Oxide Nanoparticles (SPIONs) as theranostic tools for early detection of Alzheimer's disease were also discussed.

Sleep Duration and Frailty Risk among Older Adults: Evidence from a Retrospective, Population-Based Cohort Study

OBJECTIVES

Frailty and sleep duration complaints are both prevalent and often coexist among older adults. The purpose of this study was to examine the prospective association between sleep duration and frailty risk in a nationally representative cohort study.

DESIGN

Prospective cohort study, ten-year follow-up.

SETTING

Community-based setting in 23 provinces of China.

PARTICIPANTS

A total of 7623 older adults age 65 and over without frailty at baseline were included in the analysis.

MEASUREMENTS

The participants were divided into three groups according to self-reported sleep duration: short (≤6 hours per day), middle (>6 but <10 hours per day) and long (≥10 hours per day). Frailty was measured according to the accumulation of health deficits by the construction of a frailty index of 38 items with 0.25 as the cutoff. A Cox proportional hazard model, a competing risk model and a generalized estimating equation (GEE) model with multiple adjustments were performed to evaluate the association between sleep duration and frailty risk.

RESULTS

During a median follow-up period of 4.4 years (IQR 2.9-9.0), 2531 (33.2%) individuals developed frailty. Compared with participants with middle sleep duration, the risk of frailty was increased among participants with long sleep duration (HR 1.26, 95% CI 1.14-1.38) in the fully adjusted Cox proportional hazard model. However, short sleep duration was insignificantly associated with frailty risk. The competing risk model and the GEE model yielded similar results.

CONCLUSION

Long sleep duration is significantly associated with frailty incidence among older adults even after adjustment for confounding factors. This study provides reinforcing longitudinal evidence for the need to design sleep quality improvement interventions in health care programs to prevent frailty among older adults.

Residential elevation and its effects on hypertension incidence among older adults living at low altitudes: a prospective cohort study

Background

Research on the relationship between residential altitude and hypertension incidence has been inconclusive. Evidence at low altitudes (i.e., <1,500 m) is scarce, let alone in older adults, a population segment with the highest hypertension prevalence. Thus, the objective of this study is to determine whether hypertension risk may be affected by altitude in older adults living at low altitudes.

Methods

This prospective cohort study collected data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS). We selected 6,548 older adults (≥65 years) without hypertension at baseline (2008) and assessed events by the follow-up surveys done in 2011, 2014, and 2018 waves. The mean altitude of 613 residential units (county or district) in which the participants resided was extracted from the Digital Elevation Model (DEM) of the National Aeronautics and Space Administration (NASA) and was accurate to within 30 m. The Cox regression model with penalized splines examined the linear or nonlinear link between altitude and hypertension. A random-effects Cox regression model was used to explore the linear association between altitude and hypertension.

Results

The overall rate of incident hypertension was 8.6 per 100-person years. The median altitude was 130.0 m (interquartile range [IQR] = 315.5 m). We observed that the exposure–response association between altitude and hypertension incidence was not linear. The shape of the exposure–response curve showed that three change points existed. Hypertension risk increased from the lowest to the first change point (247.1 m) and slightly fluctuated until the last change point (633.9 m). The risk decreased above the last change point. According to the categories stratified by the change points, altitude was only significantly associated with hypertension risk (hazard ratio [HR] = 1.003; 95% confidence interval [CI] = 1.002–1.005) under the first change point (247.1 m) after adjusting for related covariates.

Conclusion

Our study found that the association between altitude and hypertension risk might not be linear. We hope the further study can be conducted to confirm the generality of our findings.

Supplementary information

The online version contains supplementary material available at https://doi.org/10.1265/ehpm.22-00001.

The impact of environmental pollution on the physical health of middle-aged and older adults in China

While several studies have demonstrated the negative impacts of environmental pollution on population health, in general, few studies have examined the potential differential effects on the physical health of middle-aged and older populations, i.e., 45 years and older. Given the twin concerns of environmental pollution and population aging in China, this article employed a fixed effects model to infer the impact of environmental pollution on public health with a particular focus on middle-aged and older adults. The analyses were based on data from the 2011 to 2018 waves of the CHARLS and pollutant data from prefecture-level cities. The results showed that both the level and intensity of environmental pollution significantly increased the risk of chronic diseases and negatively impacted the physical health of middle-aged and older adults. Environmental pollution had its greatest negative effect on the physical health of the elderly, urban residents, residents of the Eastern region, and those with lower incomes than their counterparts. We further found that the potential channels of health effect were through reduced physical exercise and sleep duration and an increase in depressive symptoms, and the pollution prevention actions alleviated the health deterioration of environmental pollution for the middle-aged and the elderly. It is imperative for the government to urgently reinforce policy enforcement to decrease air and water pollution and enhance the ability to circumvent pollution for the lower socioeconomic groups.

Cognitive impairment and all-cause mortality among Chinese adults aged 80 years or older

OBJECTIVES

The oldest-old (aged ≥80 years) are the fastest growing population segment and age is related to cognitive impairment. We aimed to estimate the association between cognitive impairment and all-cause mortality, in addition to the relationship with different cognitive subdomains among the oldest-old in China.

METHODS

We analyzed 25,285 participants recruited from 22 out of 30 provinces in the Chinese Longitudinal Healthy Longevity Survey (CLHLS) from 1998 to 2008, with mortality follow-up until 2014. Cognitive function was measured by the Chinese-version 30-item Mini-Mental State Examination (MMSE), classified as no (MMSE score: 25-30), mild (18-24), moderate (10-17), and severe (0-9) impairment. We used time-dependent Cox model to evaluate the relationship between time-varying cognition and mortality.

RESULTS

The relationship between cognition and mortality showed a dose-response pattern among the overall population. Compared to those with no impairment, participants with moderate (HR = 1.41, 95% CI 1.28-1.56) and severe (HR = 1.77, 95% CI 1.59-1.96) cognitive impairment showed increased mortality risk. Impairment in the subdomain of orientation was independently associated with increased mortality risk (HR = 1.20, 95% CI 1.05-1.36) among participants without overall cognitive impairment. Urban and rural residents had similar mortality risk.

CONCLUSIONS

A consistent dose-response pattern existed between cognitive impairment and all-cause mortality. Orientation was associated with mortality in the population without cognitive impairment. Similar mortality regardless of residence areas indicated scarce health care and treatment for cognitive impairment in China from 1998 to 2014.

Cooking with biomass fuels increased the risk for cognitive impairment and cognitive decline among the oldest-old Chinese adults (2011-2018): A prospective cohort study

BACKGROUNDS

While the pernicious effects of outdoor air pollution on cognitive ability have been previously examined, evidence regarding household air pollution is scarce.

METHODS

Using data from the Chinese Longitudinal Healthy Longevity Survey, we explored the relationship between cooking with biomass fuel and cognitive impairment and cognitive decline using a Cox proportional hazards model. We further assessed the correlation of biomass fuels and cognitive score using a generalized estimating equation. Cognitive ability was measured based on the Chinese version of the Mini-Mental State Examination (MMSE) and cognitive impairment was defined as MMSE < 24 points and cognitive decline was defined as a reduction of MMSE ≥ 3 points. On follow-up, we investigated the effect of switch-cooking combustibles on cognitive ability.

RESULTS

The mean (SD) age of 4161 participants was 81.7 (10.0) years old. The reported cooking with biomass fuels was correlated with an elevated risk of cognitive impairment (hazard ratio (HR): 1.19, 95% confidence interval (CI): 1.04, 1.37) and cognitive decline (HR: 1.18, 95% CI: 1.04, 1.33). Besides, cooking with biomass fuels was related to a decrease in cognitive score (β: -0.43, 95% CI: -0.73, -0.14). In comparison to persistent biomass fuel users, participants who reported changing their primary cooking fuels from biomass to clean fuels exhibited a reduced risk of cognitive impairment (HR: 0.68, 95% CI: 0.57, 0.82) and cognitive decline (HR: 0.66, 95% CI: 0.56, 0.76) and a higher cognitive score (β: 0.72, 95% CI: 0.17, 1.26). Cooking without ventilated cookstoves was associated with a higher risk of cognitive impairment (HR: 1.31, 95% CI: 1.10, 1.58) and cognitive decline (HR: 1.18, 95% CI: 1.02, 1.38), regardless of types of cooking fuels. Interaction and stratified analyses showed relatively poor cognitive ability in participants who engaged in irregular exercise or were not living with family members.

CONCLUSIONS

Cooking with biomass fuels was correlated with a higher risk of cognitive impairment and cognitive decline. Among the oldest-old population, this risk may, however, be lower for those changing their primary cooking fuels from biomass to clean fuels.

Examining air pollution (PM10), mental health and well-being in a representative German sample

There is a growing debate on the role of the physical environment and what constitute risk and protective factors for mental health. Various forms of air pollution have shown links to physical and mental health concerns and considering that Germany does not meet the WHO air quality standards-poor air quality affects a large proportion of Germans and is more important now than ever. This study investigates the physical environmental factor, air pollution, measured by particulate matter of particles with an aerodynamic diameter smaller than 10 µm (PM10) and effects on determinants of mental health and well-being (life satisfaction, stress resilience, anxiety, depression, and self-esteem). A representative sample of N = 3020 German adults with 54% females (46% males) and an age range between 18 and 92 years (M = 49.04, S.D. ± 17.27) was used. Multivariate linear regression analyses show that higher life satisfaction, more self-esteem and higher stress resilience are predicted by less air pollution (PM10). Individual income, age, and gender were taken into account for each regression model. Gender specific sub-analyses revealed similar predictions for PM10 and stress resilience whereas PM10 and self-esteem were only significantly associated for females. Associations between mental health or well-being determinants and air pollution (PM10) are found in the representative German sample.

Exposure to Air Pollution in Relation to Risk of Dementia and Related Outcomes: An Updated Systematic Review of the Epidemiological Literature

BACKGROUND

Dementia is a devastating neurologic condition that is common in older adults. We previously reviewed the epidemiological evidence examining the hypothesis that long-term exposure to air pollution affects dementia risk. Since then, the evidence base has expanded rapidly.

OBJECTIVES

With this update, we collectively review new and previously identified epidemiological studies on air pollution and late-life cognitive health, highlighting new developments and critically discussing the merits of the evidence.

METHODS

Using a registered protocol (PROSPERO 2020 CRD42020152943), we updated our literature review to capture studies published through 31 December 2020, extracted data, and conducted a bias assessment.

RESULTS

We identified 66 papers (49 new) for inclusion in this review. Cognitive level remained the most commonly considered outcome, and particulate matter (PM) remained the most commonly considered air pollutant. Since our prior review, exposure estimation methods in this research have improved, and more papers have looked at cognitive change, neuroimaging, and incident cognitive impairment/dementia, though methodological concerns remain common. Many studies continue to rely on administrative records to ascertain dementia, have high potential for selection bias, and adjust for putative mediating factors in primary models. A subset of 35 studies met strict quality criteria. Although high-quality studies of fine particulate matter with aerodynamic diameter ≤ 2.5 μ m (PM 2.5 ) and cognitive decline generally supported an adverse association, other findings related to PM 2.5 and findings related to particulate matter with aerodynamic diameter ≤ 10 μ m (PM 10 , NO 2 , and NO x ) were inconclusive, and too few papers reported findings with ozone to comment on the likely direction of association. Notably, only a few findings on dementia were included for consideration on the basis of quality criteria.

DISCUSSION

Strong conclusions remain elusive, although the weight of the evidence suggests an adverse association between PM 2.5 and cognitive decline. However, we note a continued need to confront methodological challenges in this line of research. https://doi.org/10.1289/EHP8716.

Self-reported hearing difficulty increases 3-year risk of incident cognitive impairment: The role of leisure activities and psychological resilience

OBJECTIVE

Although hearing difficulty is associated with cognitive impairment, little is known about the potential mechanisms involved. This study assessed the mediating effects of leisure activities and psychological resilience on the association between hearing difficulty and cognitive impairment.

METHODS

Two waves of Chinese Longitudinal Healthy Longevity Survey (2011-2014) were used in the current analysis. Hearing difficulty, leisure activities and psychological resilience were measured at baseline. Cognitive function was assessed using the Chinese version of the Mini-Mental State Examination. The data were analyzed using generalized structural equation modeling with adjustment for confounding factors.

RESULTS

Of the 4267 participants at baseline, 33.5% (1430) reported hearing difficulty. The incidence of cognitive impairment was 15.3% (651) during the 3-year follow-up. Hearing difficulty increased the risk of cognitive impairment (odds ratio [OR] = 1.59, 95% confidence intervals [CI]: 1.26-1.92). Leisure activities and psychological resilience partly mediated the association between hearing difficulty and cognitive impairment. Hearing difficulty was negatively related to leisure activities (β = -0.23, 95% CI: -0.41 to -0.05) and psychological resilience (β = -0.34, 95% CI: -0.57 to -0.11). Furthermore, leisure activities (OR = 0.92, 95% CI: 0.89-0.96) and psychological resilience (OR = 0.95, 95% CI: 0.93-0.98) would significantly decrease the risk of cognitive impairment.

CONCLUSIONS

Hearing difficulty was associated with the incidence of cognitive impairment in older adults. Leisure activities and psychological resilience mediated the relationship. Participation in leisure activity and promoting psychological resilience may be candidate interventions in preventing cognitive impairment among the individuals with hearing difficulty.

How Does an Environmental Amenity Attract Voluntary Migrants? Evidence from Ambient Air Quality in China

Recent studies have shown that air quality is an important amenity for population relocation in China. However, much of Chinese internal migration occurs due to non-discretionary reasons, such as government policies, family considerations, and military personnel reassignments. As such, estimates of the impact of environmental amenities on migration that do not control for migration reasons may be biased. Using the 2015 China Migrants Dynamic Survey, this paper estimates the impact of ambient air pollution on voluntary migration to other provinces for work. We find that more polluted days (air quality index (AQI) > 150) at the original residence leads to a significant increase in labor out-migration to a province with better air quality, providing evidence of the current migration trend leading to declining populations in China’s megacities. Our findings indicate that environmental migration is more favored among households that are less educated, are older, work overtime, and have lower income, suggesting that environmental migration may result from environmental health inequalities in socially disadvantaged families.

Is the 2003 SARS epidemic over? Long-term effects of epidemic exposure on mortality among older adults

Infectious diseases put health of millions at risk and induce large socioeconomic costs each year. However, the long-term effects of exposure to infectious diseases on the elderly have received minimal attention. Using data from the Chinese Longitudinal Healthy Longevity Survey, this study adopts a differences-in-differences strategy to evaluate the long-term effects of epidemic exposure on old-age mortality. We find that intense exposure to the severe acute respiratory syndrome (SARS) epidemic led to an increase in old-age mortality after the SARS outbreak. We provide some suggestive evidence that exposure to SARS increased psychological stress and limitations in physical activities among old people.

Age-friendly neighbourhoods and depression among older people in China: Evidence from China Family Panel Studies

BACKGROUND

Older population with depression symptoms reached about 64 million in China. Under the World Health Organization's (WHO) age-friendly communities framework, this study explored relationships between neighbourhood environment characteristics and depressive symptoms among community-dwelling older adults in China.

METHODS

Data were obtained from the China Family Panel Studies (CFPS), a national multi-stage probability sample in China. The final analytic sample comprised 5,641 older adults in China. Neighbourhood environment characteristics were measured in three ways: objective facilities, interviewers' evaluation, and respondents' own perceptions on the neighbourhood environment. Depressive symptoms were measured by the 20-item version of the Center for Epidemiologic Studies Depression Scale (CES-D). Multilevel regression models were applied.

RESULTS

Neighbourhoods with more exercise and recreational facilities, better interviewers' evaluations, and better objective respondents' perceptions on neighbourhood environment at a neighbourhood level were significantly negatively associated with depressive symptoms, but these association were influenced by respondents' demographic characteristics, socioeconomic status and respondents' own perceptions of neighbourhood environment at the individual level. On the other hand, respondents' subjective positive perceptions of neighbourhood environment at the individual level were also significantly negatively associated with depressive symptoms.

LIMITATIONS

The actual conditions of affordability, accessibility and utilization of public facilities and social services within neighbourhoods were not known.

CONCLUSIONS

This research extended the current knowledge of the associations between neighbourhoods and mental health among older adults, to promote ageing in place in China. Great importance should be attached to the improvement of both physical and social aspects of the neighbourhoods to develop age-friendly communities.

Toileting Disability Among Older Adults in China and Role of Environmental Factors

Objectives: We investigated the risk factors associated with toileting disability among older adults in China, focusing on environmental factors (physical, social, and external supports). Methods: Data were drawn from the WHO's SAGE wave 1. We proposed a conceptual framework to guide the selection of risk factors, and implemented logistic regressions separately for urban and rural subpopulations. Results: In both subsamples, older adults who relied on assistive devices were about three times more likely to be toileting-disabled. Rural residents using non-flush toilets were 1.94 more likely to have difficulty toileting than those using flush system toilets. Sharing toilets and did not feel safe in homes were also positively associated with toileting disability. For urban residents, low neighborhood trust was weakly predictive of higher odds of toileting disability. Discussion: This study highlights the importance of environmental factors in explaining toileting disability, and the potential for related policy interventions in developing countries.

The development of Need-Threat Internal Resiliency Theory in COVID-19 crisis utilizing deductive axiomatic approach

Resiliency for older people represents the capacity to return to equilibrium when difficulties arise and was found as integral predictor of their health status. This study aims to develop a theory that attempts to explain the older adults' resiliency perspectives during crisis and how it has affected their well-being and quality of life as population group. Deductive theory generation using axiomatic approach was adopted resulting to five axioms that served as basis for the generation of three propositions such as: (1) An older person's health needs have tendencies to develop into a health threat, (2) when the threat is perceived, older persons developed a sense of internal control and adaptation to the changes it creates known as internal resiliency, and (3) internal resiliency can influence the quality of life in old age. The evolved theory suggests that in times of crisis (e.g., COVID-19 pandemic), health needs develop into a health threat that compels older persons to develop internal resiliency in order to preserve their integrity, wellbeing and quality of life. This study widens the nursing perspectives in addressing older persons' resiliency by the unique condition at which older clients are placed affecting both the pathological nature of the illness as well as the preventive interventions which the society is forced to implement.

Multidimensional healthy life expectancy of the older population in China

Research on healthy life expectancy (HLE) that considers cognitive impairment has been inadequate, particularly in the context of less developed countries. Using data from the China Health and Retirement Longitudinal Study, our study fills this research gap by computing active life expectancy (ALE), cognitive-impairment-free life expectancy (CIFLE), and active and cognitive-impairment-free life expectancy (ACIFLE) for China's older population, using multistate life tables. Results show that at age 60, the three life expectancies were 19.4 years (ALE), 9.5 years (CIFLE), and 8.8 years (ACIFLE) during the period 2011-13. HLE exhibits significant differentials by sex, urban/rural residence, educational level, marital status, and health status at age 60. Among China's older people, males and those living in urban areas experience higher CIFLE, and those who live with a spouse, are more educated, and are healthy at age 60 expect more years in good health according to all three HLE measures.Supplementary material for this article is available at: https://doi.org/10.1080/00324728.2021.1914854.

Residential proximity to major roadways and cognitive function among Chinese adults 65 years and older

Emerging evidence in North America and Europe suggests that traffic-related air pollution (TRAP) adversely affects cognition. However, little is known about this relationship in people living in low- and middle-income countries (LMICs). It is also unknown whether indoor air pollution can modify the effect of TRAP. We derived data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS), a prospective cohort study, including 11,187 individuals of 82.0 years old (53.9% female). We ascertained residential proximity to major roadways based on self-reports and assessed cognitive function using the Mini-Mental State Examination (MMSE). We used cooking fuel type and home ventilation as proxies for indoor air pollution. We examined the associations between major road proximity and cognitive impairment using multivariable logistic regressions, controlling for demographic, lifestyle, socioeconomic status, and chronic conditions. We did subgroup analyses and assessed the potential interaction effect. The prevalence of cognitive impairment was 33.4%. The adjusted odds ratios of cognitive impairment were 1.20 (1.05, 1.35), 1.26 (1.09, 1.46), 0.99 (0.84, 1.17), and 1.05 (0.88, 1.25) for individuals living <50 m, 50-100 m, 101-200 m, and 201-300 m compared to those living >300 m from a major roadway. In dichotomized analyses, the risk (OR) associated with living closer to roadways was greater in participants who did not implement any ventilation during cooking (compared to those using natural or mechanical ventilation, 1.86 [1.31-2.65] vs. 1.16 [1.03-1.26], P for interaction = 0.001) and in solid fuel users (compared to clean fuel users, 1.37 [1.13-1.67] vs. 1.13 [1.04-1.21], P for interaction = 0.028). The associations were robust in a set of sensitivity analyses. The results suggested that living closer to major roadways was associated with an increased risk for cognitive impairment in older adults in China, indicating an adverse TRAP effect. Indoor air pollution appeared to enhance the TRAP effect synergistically.

A critical review of the epidemiological evidence of effects of air pollution on dementia, cognitive function and cognitive decline in adult population

Dementia is arguably the most pressing public health challenge of our age. Since dementia does not have a cure, identifying risk factors that can be controlled has become paramount to reduce the personal, societal and economic burden of dementia. The relationship between exposure to air pollution and effects on cognitive function, cognitive decline and dementia has stimulated increasing scientific interest in the past few years. This review of the literature critically examines the available epidemiological evidence of associations between exposure to ambient air pollutants, cognitive performance, acceleration of cognitive decline, risk of developing dementia, neuroimaging and neurological biomarker studies, following Bradford Hill guidelines for causality. The evidence reviewed has been consistent in reporting associations between chronic exposure to air pollution and reduced global cognition, as well as impairment in specific cognitive domains including visuo-spatial abilities. Cognitive decline and dementia incidence have also been consistently associated with exposure to air pollution. The neuro-imaging studies reviewed report associations between exposure to air pollution and white matter volume reduction. Other reported effects include reduction in gray matter, larger ventricular volume, and smaller corpus callosum. Findings relating to ischemic (white matter hyperintensities/silent cerebral infarcts) and hemorrhagic (cerebral microbleeds) markers of cerebral small vessel disease have been heterogeneous, as have observations on hippocampal volume and air pollution. The few studies available on neuro-inflammation tend to report associations with exposure to air pollution. Several effect modifiers have been suggested in the literature, but more replication studies are required. Traditional confounding factors have been controlled or adjusted for in most of the reviewed studies. Additional confounding factors have also been considered, but the inclusion of these has varied among the different studies. Despite all the efforts to adjust for confounding factors, residual confounding cannot be completely ruled out, especially since the factors affecting cognition and dementia are not yet fully understood. The available evidence meets many of the Bradford Hill guidelines for causality. The reported associations between a range of air pollutants and effects on cognitive function in older people, including the acceleration of cognitive decline and the induction of dementia, are likely to be causal in nature. However, the diversity of study designs, air pollutants and endpoints examined precludes the attribution of these adverse effects to a single class of pollutant and makes meta-analysis inappropriate.

Bathing and toileting difficulties of older adults in rural China: the role of environment

BACKGROUND

For older adults, difficulties in bathing and toileting are often the most prevalent in the index of Activities of daily living (ADL). This study aims to examine how environmental factors are associated with difficulty of bathing and toileting among older adults in rural China.

METHOD

The data are from the 2014 Thousand-Village Survey (TVS), a national survey of Chinese rural residents of old age. The sample consists of 10,689 subjects, 55 years or older, from 536 villages across all provinces of China. Logistic regressions were applied to examine how difficulty of bathing and toileting was related to environmental factors such as geographic location, neighbourhood amenity, and related facilities of bathing and toileting.

RESULTS

Older adults living in the Southern regions of China had lesser difficulty in bathing and toileting than those living in Northern China, controlling for other confounders. Better neighbourhood conditions also reduced the likelihood of having such disabilities. Persons who bathed indoors without showering facilities, in public facilities, and outdoors were significantly more likely to have bathing disability than those who showered indoors with facility. Rural older adults who used pedestal pans and indoor buckets for toileting were more likely to have toileting disability than those who used indoor squatting facilities.

CONCLUSION

Environmental barriers were associated with functional disability among older adults in rural China, but the disabled individuals may change their environments to adapt to their functional capabilities. Our findings suggest that it is imperative to promote the use of showering facilities and pedestal pans for toileting in rural China.

Poverty increases the risk of incident cognitive impairment among older adults: a longitudinal study in China

Objectives: With a longitudinal design, we aimed to investigate the relationship between poverty and the risk of incident cognitive impairment in China.Methods: We used three waves of the Chinese Longitudinal Healthy Longevity Survey (2008-2014). Cognitive impairment was assessed using the Chinese version of the Mini Mental State Examination. Poverty was measured according to the latest national poverty line settled at an annual per-capita income of 2300 yuan (approximately equivalent to 1.25 dollar/day) in 2011 in China. A marginal structural model was utilized to explore the association between poverty and the risk of incident cognitive impairment. The subgroup analyses were also conducted in this study.Results: The cumulative incidence of cognitive impairment over 6 years was 30.69% (1936/6309). Poverty increased 34% risk of incident cognitive impairment in the elderly (odds ratio = 1.34, 95% confidence interval (CI): 1.15-1.56) after controlling behavioral factors and health status covariates. Participants who were male (OR = 1.38, 95% CI: 1.08-1.76), lived in urban areas (OR = 1.55, 95% CI: 1.22-1.98), and were married (OR = 1.72, 95% CI: 1.28-2.32) had higher poverty risks on incident cognitive impairment in subgroup analyses.Conclusions: Our results provide empirical support for the ongoing discussion about how economic hardship impacts of cognitive functioning, and highlight the negative health risks that economically disadvantaged individuals may experience.

Air Pollution and Dementia: A Systematic Review

Background:

Both air pollution and dementia are current and growing global issues. There are plausible links between exposure to specific air pollutants and dementia.

Objective:

To systematically review the evidence base with respect to the relationship between air pollution and later cognitive decline and dementia.

Methods:

Medline, Embase, and PsychINFO^® were searched from their inception to September 2018, for publications reporting on longitudinal studies of exposure to air pollution and incident dementia or cognitive decline in adults. Studies reporting on exposure to tobacco smoke including passive smoking or on occupational exposure to pollutants were excluded. Using standard Cochrane methodology, two readers identified relevant abstracts, read full text publications, and extracted data into structured tables from relevant papers, as defined by inclusion and exclusion criteria. Papers were also assessed for validity. CRD42018094299

Results:

From 3,720 records, 13 papers were found to be relevant, with studies from the USA, Canada, Taiwan, Sweden, and the UK. Study follow-up ranged from one to 15 years. Pollutants examined included particulate matter ≤2.5 μ (PM_2.5), nitrogen dioxide (NO₂), nitrous oxides (NO_x), carbon monoxide (CO), and ozone. Studies varied in their methodology, population selection, assessment of exposure to pollution, and method of cognitive testing. Greater exposure to PM_2.5, NO₂/NO_x, and CO were all associated with increased risk of dementia. The evidence for air pollutant exposure and cognitive decline was more equivocal.

Conclusion:

Evidence is emerging that greater exposure to airborne pollutants is associated with increased risk of dementia.