Stroke is a severe cerebrovascular disease. This study aimed to determine the association between triglyceride‑glucose (TyG) index and stroke among middle-aged and elderly Chinese. Data was extracted from China Health and Retirement Longitudinal Study survey 2015 and survey 2018. Logistic regression, trend test and subgroup analysis were conducted to assess the association. Possible nonlinear relationships were explored with restricted cubic spline (RCS). Propensity score matching (PSM) was conducted to attenuate the effect of confounding factors. ORs of stroke was positively associated with TyG index. The ORs in RCS analysis also increased with the rising TyG, though p for non-linearity was bigger than 0.05. After PSM, the ORs in the full adjusted models were 1.28 (1.01, 1.62). TyG was suggested as an independent risk factor for stroke in the middle aged and elderly Chinese.

OBJECTIVE: To investigate the associations between the most popular social media platform WeChat usage and cognitive performance among the middle-aged and older Chinese population using data from a nationally representative survey.
METHODS: In total, 17,472 participants (≥ 45 years old) from the China Health and Retirement Longitudinal Study (CHARLS, Wave 4, 2018) were analyzed. Cognitive performance including episodic memory and executive function was assessed using Mini-Mental Status Examination (MMSE). Other confounding variables included socio-economic characteristics, medical status, and lifestyle-related information. Multiple linear regression models were used to test the association between cognitive performance and WeChat usage by introducing covariates hierarchically. Subgroup analyses of age and gender were conducted to estimate the robustness of the primary findings.
RESULTS: After adjusting for multiple confounders across all linear models, WeChat usage is significantly associated with executive function, episodic memory, and global cognitive performance (all p values<0.05). Such results remained robust in subgroup analyses, stratified by age and gender, and also verified according to longitudinal analyses. Compared to \'Chat-only\' users who only used WeChat for online interpersonal communication, further usage of WeChat functions such as using \'Moments\' appeared to be significantly associated with better cognitive performance, especially for episodic memory.
CONCLUSIONS: Social media usage is significantly and positively associated with better cognitive performance among the middle-aged and older Chinese population. Along with point-to-point messaging, using \'Moments\' and extended social media platform functions may correlate to better cognitive performance.

BACKGROUND: In the context of the present global aging phenomenon, the senior population and pace of aging in China have emerged as prominent issues on the worldwide stage. Frailty, a complicated condition that is closely linked to the clinical syndrome of advancing age, poses a considerable health risk to older individuals. Frailty status was assessed by the frailty index (FI) ranging from 0 to 1, pre-frailty was defined as >0.10 to <0.25, and frailty was defined as ≥0.25. To look at the connection between modifiable risk factors and frailty progression among individuals in the pre-frailty population.
METHODS: Using pre-frailty patients as characterized by the 32-frailty index, the study focused on middle-aged and elderly persons from China and ultimately recruited 5,411 participants for analysis. The relationship between modifiable factors and changes in pre-frailty status throughout follow-up was investigated. Modifiable factors were body mass index (BMI), abdominal obesity, smoking status, alcohol use, and sleep status. We employed logistic regression to examine the relationships between modifiable risk factors and changes in pre-frailty status, as well as the associations between modifiable factors scores and the corresponding pre-frailty progression. Additionally, we generated the modifiable factors scores and examined how these related to modifications in the pre-frailty stage.
RESULTS: In this study, after a mean follow-up of 6 years, (OR = 0.59, 95%CI: 0.48-0.71) for BMI ≥ 25 kg/m2 and (OR = 0.74, 95%CI: 0.63-0.89) for concomitant abdominal obesity were significantly associated with lower reversal to a healthy state; (OR = 1.24, 95%CI:1.07-1.44) and (OR = 1.25, 95%CI: 1.10-1.42) for the group that negatively progressed further to frailty were significantly associated with increased frailty progression profile. Subsequently, investigation of modifiable factor scores and changes of pre-frailty status found that as scores increased further, frailty developed (OR = 1.12, 95%CI:1.05-1.18), with scores of 3 and 4 of (OR = 1.38, 95%CI: 1.08-1.77) and (OR = 1.52, 95%CI:1.09-2.14). Finally, we also performed a series of stratified analyses and found that rural unmarried men aged 45 to 60 years with less than a high school degree were more likely to develop a frailty state once they developed abdominal obesity.
CONCLUSIONS: In pre-frailty individuals, maintaining more favorable controllable variables considerably enhances the chance of return to normal and, conversely, increase the risk of progressing to the frailty.

UNASSIGNED: Cardiometabolic disease is skyrocketing to epidemic proportions due to the high prevalence of its components and the aging of the worldwide population. More efforts are needed to improve cardiometabolic health. The aim of this nationally representative study based on the China Health and Retirement Longitudinal Study (CHARLS, 2014-2018) was to examine the association between reproductive factors and cardiometabolic disease among Chinese women aged ≥45 years.
UNASSIGNED: The CHARLS is an ongoing longitudinal study initiated in 2011, and the latest follow-up was completed in 2018. In total, 6,407 participants were analyzed. Effect-sizes are expressed as odds ratios (OR) and 95% confidence intervals (CI). Confounding was considered from statistical adjustment, subsidiary exploration, and unmeasured confounding assessment aspects.
UNASSIGNED: Of 6,407 accessible participants, 60.9% were recorded as having one or more of five predefined cardiovascular or metabolic disorders. Compared to those with two children, participants who had 0-1 child were found to have a lower risk of cardiometabolic disease (OR = 0.844, 95% CI: 0.714-0.998), and those who had ≥3 children had a greater risk (OR = 1.181, 95% CI: 1.027-1.357). Age at menarche of 16-18 years was a protective factor compared with ≤16 years of age (OR = 0.858, 95% CI: 0.749-0.982). In contrast, participants with a history of abortion were 1.212 times more likely to have cardiometabolic disorders (OR = 1.212, 95% CI: 1.006-1.465). The likelihood for the presence of unmeasured confounding was low, as reflected by E-values.
UNASSIGNED: Our findings demonstrate that number of children, age at menarche, and history of abortion were associated with a significant risk of cardiometabolic disease among Chinese women aged ≥45 years.

Objectives: This study examined the association between self-reported visual difficulty and age-related cognitive declines among older Chinese adults and how the timing of visual difficulty onset plays a role in cognitive trajectories. Methods: Data were drawn from the 2011-2018 wave of the China Health and Retirement Longitudinal Study, involving 9974 respondents aged 60 years or older (mean age 65.44 years, range 60-101 years). Results: At baseline, 14.16% respondents had self-reported visual difficulty. Growth curve models showed that Chinese older adults with visual difficulty experienced a faster decline in cognitive function compared to those without visual difficulty (β = -0.02, p < .01). Older adults who began experiencing visual difficulty between 61 and 75 years of age had steeper cognitive declines compared to those with earlier or later onset (β = -0.05, p < .01). Discussion: Older adults with self-reported visual difficulty experience faster rates of cognitive decline. Future research should explore potential factors that underlie the association between onset timing of visual difficulty and cognitive function.

This study aimed to examine the risk and protective factors associated with depression in middle-aged and older Chinese adults with activity limitations. Data were obtained from the 2018 Wave 4 Survey of the China Health and Retirement Longitudinal Study. In the logistic regression analysis, health and functioning, losing a child, and a perceived lack of future assistance with daily activities increased the odds of depression. Conversely, receiving adequate assistance with daily activities lessened the depressive impacts of activity limitations, as indicated by a significant interaction effect. Enhanced long-term support for individuals with disabilities is necessary to improve mental health.

BACKGROUND: There is little epidemiological evidence on the relationship of dynapenic abdominal obesity (DAO) and the development of functional disability, particularly in Asian populations. We aimed to investigate the association of DAO with new-onset functional disability in Chinese adults.
METHODS: A total of 7881 participants aged ≥45 years from China Health and Retirement Longitudinal Study (CHARLS) in 2011 and 2015 were included in the study. Dynapenia and abdominal obesity were respectively defined based on handgrip strength (<28 kg for male and <18 kg for female) and waist circumference (≥ 90 cm for male and ≥85 cm for female). The sample was divided into four groups: non-dynapenic/non-abdominal obesity (ND/NAO), non-dynapenic/abdominal obesity (ND/AO), dynapenic/non-abdominal obesity (D/NAO) and dynapenic/abdominal obesity (D/AO). Functional status was assessed by basic activities of daily living (BADL) or instrumental activities of daily living (IADL). Logistic regression model was used to explore the longitudinal association between dynapenic abdominal obesity and incident functional disability.
RESULTS: After a 4-year follow-up, 1153 (14.6 %) developed BADL disability and 1335 (16.9 %) developed IADL disability. The multivariable-adjusted odds ratios (95 % CIs) for the D/AO versus ND/NAO were 2.21 (1.61-3.03) for BADL disability, and 1.68 (1.23-2.30) for IADL disability. In addition, DAO was associated with an increased risk for functional dependency severity (odds ratio, 2.08 [95 % CI, 1.57-2.75]).
CONCLUSIONS: DAO was significantly associated with greater risk of functional disability among Chinese middle-aged and older adults. Our findings indicated that interventions targeted DAO might be effective in the primary prevention of functional disability.

BACKGROUND: Cardiovascular disease (CVD) caused by air pollution poses a considerable burden on public health. We aim to examine whether lifestyle factors mediate the associations of air pollutant exposure with the risk of CVD and the extent of the interaction between lifestyles and air pollutant exposure regarding CVD outcomes.
METHODS: We included 7000 participants in 2011-2012 and followed up until 2018. The lifestyle evaluation consists of six factors as proxies, including blood pressure, blood glucose, blood lipids, body mass index, tobacco exposure, and physical activity, and the participants were categorized into three lifestyle groups according to the number of ideal factors (unfavorable, 0-1; intermediate, 2-4; and favorable, 5-6). Satellite-based spatiotemporal models were used to estimate exposure to ambient air pollutants (including particles with diameters ≤ 1.0 μm [PM1], ≤ 2.5 μm [PM2.5], ≤ 10 μm [PM10], nitrogen dioxide [NO2], and ozone [O3]). Cox regression models were used to examine the associations between air pollutant exposure, lifestyles and the risk of CVD. The mediation and modification effects of lifestyle categories on the association between air pollutant exposure and CVD were analyzed.
RESULTS: After adjusting for covariates, per 10 μg/m3 increase in exposure to PM1 (HR: 1.09, 95% CI: 1.05-1.14), PM2.5 (HR: 1.04, 95% CI: 1.00-1.08), PM10 (HR: 1.05, 95% CI: 1.03-1.08), and NO2 (HR: 1.11, 95% CI: 1.05-1.18) was associated with an increased risk of CVD. Adherence to a healthy lifestyle was associated with a reduced risk of CVD compared to an unfavorable lifestyle (HR: 0.65, 95% CI: 0.56-0.76 for intermediate lifestyle and HR: 0.41, 95% CI: 0.32-0.53 for favorable lifestyle). Lifestyle played a significant partial mediating role in the contribution of air pollutant exposure to CVD, with the mediation proportion ranging from 7.4% for PM10 to 14.3% for PM2.5. Compared to an unfavorable lifestyle, the relative excess risk due to interaction for a healthier lifestyle to reduce the effect on CVD risk was - 0.98 (- 1.52 to - 0.44) for PM1, - 0.60 (- 1.05 to - 0.14) for PM2.5, - 1.84 (- 2.59 to - 1.09) for PM10, - 1.44 (- 2.10 to - 0.79) for NO2, and - 0.60 (- 1.08, - 0.12) for O3.
CONCLUSIONS: Lifestyle partially mediated the association of air pollution with CVD, and adherence to a healthy lifestyle could protect middle-aged and elderly people from the adverse effects of air pollution regarding CVD.

OBJECTIVE: The aim of present study was to evaluate the combined effect of hypertension and activities of daily living (ADL)/instrumental activities of daily living (IADL) with the risk of CVD, stroke and cardiac events.
METHODS: A total of 14,083 participants aged 45 years or older from the China Health and Retirement longitudinal study were included in current study. Participants were divided into 4 groups according to hypertension and ADL/IADL status. Cox proportional hazards regression model was used to explore the associations between hypertension, ADL/IADL and new-onset CVD, stroke and cardiac events.
RESULTS: During the 7-year follow-up, a total of 2,324 respondents experienced CVD (including 783 stroke and 1,740 cardiac events). Individuals with limitations in ADL alone, or with hypertension alone, or with both limitations in ADL and hypertension were associated with increased risk of CVD, with the adjusted hazard ratios (95% confidence intervals) were 1.17(1.00-1.35), 1.36(1.24-1.49) and 1.44(1.23-1.68), respectively. Those with limitations in ADL and hypertension also had higher risk of stroke (hazard ratios = 1.64; 1.26-2.14) and cardiac events (hazard ratios = 1.37; 1.14-1.64). Similarly, individuals with both limitations in IADL and hypertension were associated with increased risk of CVD (hazard ratios = 1.34; 1.15-1.57), stroke (hazard ratios = 1.50; 1.17-1.95) and cardiac events (hazard ratios = 1.27; 1.06-1.53).
CONCLUSIONS: Hypertension and limitations in ADL/IADL jointly increased the risk of CVD, stroke and cardiac events.

Obesity and insulin resistance are well-known important risk factors for hypertension. This study aimed to investigate the mediating effect of the triglyceride-glucose index (TyG) in the association between Chinese visceral obesity index (CVAI) and hypertension among Chinese middle-aged and older adults.
A total of 10,322 participants aged 45 years and older from CHARLS (2011-2018) were included. Baseline data were collected in 2011 and hypertension incidence data were gathered during follow-up in 2013, 2015 and 2018. Multivariate logistic regression models were constructed to investigate the association of CVAI and TyG with the incidence of hypertension. Additionally, mediation analyses were conducted to evaluate the mediating role of the TyG index in the relationship between CVAI and hypertension. Subgroup analysis was also performed.
A total of 2,802 participants developed hypertension during the follow-up period. CVAI and TyG index were independently and significantly associated with hypertension incidence. Increasing quartiles of CVAI and TyG index were associated with high hypertension incidence in middle-aged and older adults. The TyG index was identified as a mediator in the relationship between CVAI and hypertension incidence, with a mediation effect (95% confidence interval) was 12.38% (6.75, 31.81%).
Our study found that CVAI and TyG were independently associated with hypertension incidence. TyG played a partial mediating effect in the positive association between CVAI and hypertension incidence.