Association between atherogenic index of plasma control level and incident cardiovascular disease in middle-aged and elderly Chinese individuals with abnormal glucose metabolism.

BACKGROUND: The atherogenic index of plasma (AIP) and cardiovascular disease (CVD) in participants with abnormal glucose metabolism have been linked in previous studies. However, it was unclear whether AIP control level affects the further CVD incidence among with diabetes and pre-diabetes. Therefore, our study aimed to investigate the association between AIP control level with risk of CVD in individuals with abnormal glucose metabolism. METHODS: Participants with abnormal glucose metabolism were included from the China Health and Retirement Longitudinal Study. CVD was defined as self-reporting heart disease and/or stroke. Using k-means clustering analysis, AIP control level, which was the log-transformed ratio of triglyceride to high-density lipoprotein cholesterol in molar concentration, was divided into five classes. The association between AIP control level and incident CVD among individuals with abnormal glucose metabolism was investigated multivariable logistic regression analysis and application of restricted cubic spline analysis. RESULTS: 398 (14.97%) of 2,659 participants eventually progressed to CVD within 3 years. After adjusting for various confounding factors, comparing to class 1 with the best control of the AIP, the OR for class 2 with good control was 1.31 (95% CI, 0.90-1.90), the OR for class 3 with moderate control was 1.38 (95% CI, 0.99-1.93), the OR for class 4 with worse control was 1.46 (95% CI, 1.01-2.10), and the OR for class 5 with consistently high levels was 1.56 (95% CI, 1.03-2.37). In restricted cubic spline regression, the relationship between cumulative AIP index and CVD is linear. Further subgroup analysis demonstrated that the similar results were observed in the individuals with agricultural Hukou, history of smoking, diastolic blood pressure ≥ 80mmHg, and normal body mass index. In addition, there was no interaction between the AIP control level and the subgroup variables. CONCLUSIONS: In middle-aged and elderly participants with abnormal glucose metabolism, constant higher AIP with worst control may have a higher incidence of CVD. Monitoring long-term AIP change will contribute to early identification of high risk of CVD among individuals with abnormal glucose metabolism.

Association between triglyceride glucose-waist height ratio index and cardiovascular disease in middle-aged and older Chinese individuals: a nationwide cohort study.

BACKGROUND: The triglyceride-glucose (TyG) index and its combination with obesity indicators can predict cardiovascular diseases (CVD). However, there is limited research on the relationship between changes in the triglyceride glucose-waist height ratio (TyG-WHtR) and CVD. Our study aims to investigate the relationship between the change in the TyG-WHtR and the risk of CVD. METHODS: Participants were from the China Health and Retirement Longitudinal Study (CHARLS). CVD was defined as self-reporting heart disease and stroke. Participants were divided into three groups based on changes in TyG-WHtR using K-means cluster analysis. Multivariable binary logistic regression analysis was used to examine the association between different groups (based on the change of TyG-WHtR) and CVD. A restricted cubic spline (RCS) regression model was used to explore the potential nonlinear association of the cumulative TyG-WHtR and CVD events. RESULTS: During follow-up between 2015 and 2020, 623 (18.8%) of 3312 participants developed CVD. After adjusting for various potential confounders, compared to the participants with consistently low and stable TyG-WHtR, the risk of CVD was significantly higher in participants with moderate and increasing TyG-WHtR (OR 1.28, 95%CI 1.01-1.63) and participants with high TyG-WHtR with a slowly increasing trend (OR 1.58, 95%CI 1.16-2.15). Higher levels of cumulative TyG-WHtR were independently associated with a higher risk of CVD events (per SD, OR 1.27, 95%CI 1.12-1.43). CONCLUSIONS: For middle-aged and older adults, changes in the TyG-WHtR are independently associated with the risk of CVD. Maintaining a favorable TyG index, effective weight management, and a reasonable waist circumference contribute to preventing CVD.

Association between the cumulative average triglyceride glucose-body mass index and cardiovascular disease incidence among the middle-aged and older population: a prospective nationwide cohort study in China.

BACKGROUND: Findings from earlier research have established that insulin resistance (IR) is implicated in atherosclerosis progression, representing a noteworthy risk factor for cardiovascular disease (CVD). Recently, the triglyceride glucose-body mass index (TyG-BMI) has been introduced as a straightforward and robust alternative indicator for early detection of IR. Nevertheless, there is a scarcity of studies that have examined the capability of TyG-BMI for predicting incident CVD. Consequently, the core objective of this study was to determine whether the cumulative average TyG-BMI correlated with CVD incidence. METHODS: All data was sourced from the China Health and Retirement Longitudinal Study (CHARLS). The exposure was the cumulative average TyG-BMI, determined by the average of TyG-BMI values for the baseline and follow-up investigations (Wave 1 in 2011, Wave 3 in 2015, respectively). The calculation of TyG-BMI involved a combination of triglyceride, fasting blood glucose, and body mass index. The primary outcome was incident CVD. Logistic regression analyses as well as restricted cubic spline (RCS) regression analyses were performed for examining the association between the cumulative average TyG-BMI and CVD incidence. RESULTS: In all, 5,418 participants were enrolled in our analysis, with 2,904 (53.6%) being female, and a mean (standard deviation, SD) age of 59.6 (8.8) years. The mean (SD) cumulative average TyG-BMI among all participants was 204.9 (35.7). Totally, during a 4-year follow-up, 543 (10.0%) participants developed CVD. The fully adjusted logistic regression analysis revealed a significant association between the cumulative average TyG-BMI and incident CVD [odds ratio (OR), 95% confidence interval (CI): 1.168, 1.040-1.310, per 1 SD increase]. The RCS regression analysis displayed a positive, linear association of the cumulative average TyG-BMI with CVD incidence (P for overall = 0.038, P for nonlinear = 0.436). CONCLUSIONS: Our study revealed a noteworthy correlation between the cumulative average TyG-BMI and incident CVD among the middle-aged and older population. The cumulative average TyG-BMI emerges as a valuable tool that may enhance the primary prevention and treatment of CVD.

Interacting and joint effects of triglyceride-glucose index (TyG) and body mass index on stroke risk and the mediating role of TyG in middle-aged and older Chinese adults: a nationwide prospective cohort study.

BACKGROUND: Individuals who are overweight or obese often develop insulin resistance, mediation of the association between body mass index (BMI) and stroke risk through the triglyceride-glucose index (TyG) seems plausible but has not been investigated. This study aims to examine whether TyG mediates associations of BMI with stroke risk and the extent of interaction or joint relations of TyG and BMI with stroke outcome. METHODS: The China Health and Retirement Longitudinal Study, initiated in 2011, is a nationally representative, ongoing prospective cohort study involving 8 231 middle-aged and older Chinese adults without a stroke history at baseline. Exposures examined include BMI and the TyG, the latter being the logarithmized product of fasting triglyceride and glucose concentrations. The primary study outcome is stroke incidence, as determined through self-reports, with a follow-up period extending from June 1, 2011, to June 30, 2018. RESULTS: Of the 8 231 participants, 3 815 (46.3%) were men; mean (SD) age was 59.23 (9.32) years. During a median follow-up of 7.1 years, 585 (7.1%) participants developed stroke. The TyG was found to mediate the association between BMI and incident stroke, proportions mediated were 16.3% for BMI in the 24.0-27.9 kg/m2 group and 53.8% for BMI ≥ 28.0 kg/m2 group. No significant multiplicative and additive interactions were found between BMI and TyG on incident stroke (Additive: RERI = 1.78, 95% CI - 1.29-4.86; Multiplicative, HR = 1.40, 95% CI 0.86-2.27). HRs for individuals with BMI ≥ 28.0 kg/m2 and quartile 4 of TyG compared with those with BMI < 24.0 kg/m2 and quartile 1 of TyG were 2.05 (95% CI 1.37-3.06) for incident stroke. Combining BMI and TyG enhanced predictive performance for stroke when compared to their individual (AUCBMI+TyG vs AUCBMI vs AUCTyG, 0.602 vs 0.581 vs 0.583). CONCLUSIONS: TyG appeared to be associated with stroke risk and mediates more than 50% of the total association between BMI and stroke in middle-aged and older Chinese adults. Public health efforts aiming at the reduction of body weight might decrease the stroke risk due to insulin resistance and the burden of stroke.

Assessment of six surrogate insulin resistance indexes for predicting cardiometabolic multimorbidity incidence in Chinese middle-aged and older populations: Insights from the China health and retirement longitudinal study.

AIMS: Insulin resistance (IR) is associated with cardiometabolic multimorbidity (CMM). We aimed to explore the predictive value of six surrogate IR indexes-Chinese visceral adiposity index (CVAI), lipid accumulation product (LAP), triglyceride-glucose (TyG), atherogenic index of plasma (AIP), TyG-body mass index (TyGBMI), and TyG-waist circumference (TyGwaist)-to establish the CMM incidence in Chinese middle-aged and older populations. MATERIAL AND METHODS: To estimate the odds ratio (OR) with a 95% confidence interval (95% CI) for incident CMM using six surrogates, we analysed data from the China Health and Retirement Longitudinal Study using multivariate logistic regression models. The nonlinear dose-response correlation was evaluated using restricted cubic spline analysis; predictive performance was assessed using receiver operator characteristic curves. RESULTS: Among 6451 eligible participants, 268 (4.2%) developed CMM during the 4-year follow-up period. The ORs (95% CI) for incident CMM increased with increasing CVAI quartiles (Q) [Q2: 1.71, 1.03-2.90; Q3: 2.72, 1.70-4.52; Q4: 5.16, 3.29-8.45; all p < 0.05] after full adjustment, with Q1 as the reference. Other indexes yielded similar results. These associations remained significant in individuals with a normal body mass index. Notably, CVAI, AIP, and TyG exhibited a linear dose-response relationship with CMM (Pnonlinear ≥0.05), whereas LAP, TyGBMI, and TyGwaist displayed significant nonlinear correlations (Pnonlinear <0.05). The area under the curve for the CVAI (0.691) was significantly superior to that of other indexes (all p < 0.05). CONCLUSIONS: The six IR surrogates were independently associated with CMM incidence. CVAI may be the most appropriate indicator for predicting CMM in middle-aged and older Chinese populations.

Metabolic dysfunction, rather than obesity, is a risk factor for chronic kidney disease in Chinese population.

BACKGROUND: Metabolic dysfunction and obesity are closely related to chronic kidney disease (CKD). However, studies on the relationship between various metabolic syndrome-body mass index (MetS-BMI) phenotypes and the risk of CKD in the Chinese population have not yet been explored. MATERIALS AND METHODS: Data from the China Health and Retirement Longitudinal Study (CHARLS) 2015 were analyzed in this study. This study enrolled 12,054 participants. Participants were divided into six distinct groups according to their MetS-BMI status. Across the different MetS-BMI groups, the odd ratios (ORs) for CKD were determined using multivariable logistic regression models. RESULTS: The prevalence of CKD was higher in metabolically unhealthy groups than in the corresponding healthy groups. Moreover, the fully adjusted model showed that all metabolically unhealthy individuals had an increased risk of developing CKD compared to the metabolically healthy normal weight group (OR = 1.62, p = 0.002 for the metabolically unhealthy normal weight group; OR = 1.55, p < 0.001 for the metabolically unhealthy overweight group; and OR = 1.77, p < 0.001 for the metabolically unhealthy obesity group. CONCLUSIONS: This study is the first to evaluate the relationship between the MetS-BMI phenotype and renal prognosis in the Chinese population. Individuals with normal weights are at different risk of developing CKD depending on their different metabolic phenotypes.

Revisiting the association between grandparenting and mental health in China: New evidence from the harmonized CHARLS.

BACKGROUND: In the context of the global aging challenge, an increasing number of middle-aged and older adults (MAOAs) are engaging in grandparenting. However, the effect of grandparenting on the mental health of caregivers has shown inconsistent findings. To effectively promote healthy aging, it is imperative to adopt a comprehensive perspective and employ a rigorous approach to further investigate the relationship between these two social phenomena. METHODS: The data from the Harmonized China Health and Retirement Longitudinal Study were analyzed, focusing on MAOAs with at least one grandchild. Mental health assessments used the center for epidemiologic studies depression scale scale. The study employed a series of difference-in-differences (DID) models, especially complemented by propensity score matching, to evaluate the average treatment effect for the treated (ATT) on mental health of caregivers, considering covariates like personal and family characteristics. The intervention perspective includes both the provision and cessation of grandparenting. RESULTS: The study found that providing grandchildren care does not have a significant effect on the mental health of grandparents, in comparison to those who have never engaged in such care (ATT = -0.172, T = 0.65, p = 0.517 in the PSM-DID model). Furthermore, ceasing this care also appears to have no substantial effect on the mental health of the caregivers, relative to individuals who have consistently offered grandchildren care (ATT = 0.060, T = 0.26, p = 0.795 in the PSM-DID model). Furthermore, subsequent robustness analyses consistently supported these findings, even when considering data from different survey waves. CONCLUSIONS: In contrast to many prior studies that have reported either positive or negative effects, our research reveals that grandparenting exerts no significant effect on the mental health of MAOAs. Consequently, health practitioners and policymakers should carefully consider the diverse cultural context when tailoring interventions and support strategies.

Association of estimated cardiorespiratory fitness in middle-aged and elderly people with cardiovascular disease: Evidence from the China health and retirement longitudinal study.

BACKGROUND AND AIM: Cardiovascular diseases (CVD) is a major threat to public health, while cardiorespiratory fitness (CRF) is a key predictor of chronic disease. Given this, the purpose of this study was to investigate the relationship between estimated CRF (eCRF) and CVD in middle-aged and elderly Chinese people. METHODS AND RESULTS: The China Health and Retirement Longitudinal Study (CHARLS) with 4761 individuals were included in analysis. Participants were divided into three groups according to eCRF quantile in sex subgroups. Cox proportional hazards regression models were used to explore the correlation of eCRF with CVD (stroke or cardiac events). In total, 4761 participants were included in this cohort study (2500 [52.51%] women). During a 7-year follow-up from 2011 to 2018, 796 CVDs (268 Strokes and 588 cardiac events) were recorded. In multivariable-adjusted analyses, for per 1 SD increase of eCRF, the age-adjusted risk of CVD was reduced by about 18% (HR = 0.82; 95% CI, 0.72-0.93) in men, and was reduced by about 29% (HR = 0.71; 95% CI, 0.62-0.81) in women. Similar associations were also found between eCRF and stroke and cardiac events. Both subgroup and interaction analyses showed that the interaction of age had a statistically significant effect on CVD risk. CONCLUSION: ECRF was inversely associated with CVD risk (stroke or cardiac events) in both men and women. Remarkable sex and age differences exist in the effectiveness of increasing eCRF to reduce the risk of CVD. As a potential, efficient and cost-effective risk prediction tool, eCRF deserves further attention and wide application.

A predictive model for depression in Chinese middle-aged and elderly people with physical disabilities.

BACKGROUND: Middle-aged and older adults with physical disabilities exhibit more common and severe depressive symptoms than those without physical disabilities. Such symptoms can greatly affect the physical and mental health and life expectancy of middle-aged and older persons with disabilities. METHOD: This study selected 2015 and 2018 data from the China Longitudinal Study of Health and Retirement. After analyzing the effect of age on depression, we used whether middle-aged and older adults with physical disabilities were depressed as the dependent variable and included a total of 24 predictor variables, including demographic factors, health behaviors, physical functioning and socialization, as independent variables. The data were randomly divided into training and validation sets on a 7:3 basis. LASSO regression analysis combined with binary logistic regression analysis was performed in the training set to screen the predictor variables of the model. Construct models in the training set and perform model evaluation, model visualization and internal validation. Perform external validation of the model in the validation set. RESULT: A total of 1052 middle-aged and elderly persons with physical disabilities were included in this study, and the prevalence of depression in the elderly group > middle-aged group. Restricted triple spline indicated that age had different effects on depression in the middle-aged and elderly groups. LASSO regression analysis combined with binary logistic regression screened out Gender, Location of Residential Address, Shortsightedness, Hearing, Any possible helper in the future, Alcoholic in the Past Year, Difficulty with Using the Toilet, Difficulty with Preparing Hot Meals, and Unable to work due to disability constructed the Chinese Depression Prediction Model for Middle-aged and Older People with Physical Disabilities. The nomogram shows that living in a rural area, lack of assistance, difficulties with activities of daily living, alcohol abuse, visual and hearing impairments, unemployment and being female are risk factors for depression in middle-aged and older persons with physical disabilities. The area under the ROC curve for the model, internal validation and external validation were all greater than 0.70, the mean absolute error was less than 0.02, and the recall and precision were both greater than 0.65, indicating that the model performs well in terms of discriminability, accuracy and generalisation. The DCA curve and net gain curve of the model indicate that the model has high gain in predicting depression. CONCLUSION: In this study, we showed that being female, living in rural areas, having poor vision and/or hearing, lack of assistance from others, drinking alcohol, having difficulty using the restroom and preparing food, and being unable to work due to a disability were risk factors for depression among middle-aged and older adults with physical disabilities. We developed a depression prediction model to assess the likelihood of depression in Chinese middle-aged and older adults with physical disabilities based on the above risk factors, so that early identification, intervention, and treatment can be provided to middle-aged and older adults with physical disabilities who are at high risk of developing depression.

Analysis of depression incidence and influence factors among middle-aged and elderly diabetic patients in China: based on CHARLS data.

BACKGROUND: To investigate the incidence of depression in middle-aged and elderly patients with diabetes in China and the influencing factors to provide a theoretical basis to improve the mental health of middle-aged and elderly patients with diabetes and formulate prevention, control, and intervention strategies. METHODS: The sample of this study was obtained from the China Health and Aging Tracking Survey (CHARLS) 2018 survey data, and middle-aged and older patients with diabetes(responding "Yes" to the questionnaire: "Have you ever been told by a doctor that you have diabetes or elevated blood glucose [including abnormal glucose tolerance and elevated fasting glucose]?") aged ≥ 45 years were selected as study subjects (n = 2,613 ). Depressive symptoms of the study subjects were determined using the simplified version of the Depression Scale for Epidemiological Surveys scores(a score ≥ 10 was defined as depression), influence factors were analyzed using binary logistic regression, and proportion of depressive symptoms was standardized using the sex ratio of the seventh census. RESULTS: Among the 2,613 middle-aged and elderly patients with diabetes, 1782 (68.2%) had depressive symptoms and 831 (31.8%) had no depressive symptoms. There were 481 (27.0%) patients aged 45-59 years, 978 (54.9%) aged 60-74 years, and 323 (18.1%) aged ≥ 75 years. The depression rate among middle-aged and elderly Chinese patients with diabetes after standardization correction was 67.5%. Binary logistic regression results showed that age, education level, life satisfaction, marital satisfaction, self-rated health grade, somatic pain, visual impairment, physical disability, and the presence of comorbid chronic diseases were factors that influenced the onset of depression in middle-aged and elderly Chinese patients with diabetes (P < 0.05). CONCLUSION: According to a survey analysis of the CHARLS 2018 data, depression is influenced by a combination of factors among middle-aged and elderly patients with diabetes in China. Therefore, for this population, targeted prevention and control should be carried out for key populations, such as middle-aged and elderly people, poor physical health, and low life satisfaction and marital satisfaction, from various dimensions (e.g., demographic and sociological factors, physical health status, and life satisfaction and marital satisfaction).

Establishment of a mild cognitive impairment risk model in middle-aged and older adults: a longitudinal study.

BACKGROUND: Early identification individuals at high risk of mild cognitive impairment (MCI) is essential for prevention and intervention strategies of dementia, such as Alzheimer's disease. MCI prediction considering the interdependence of predictors in longitudinal data needs to be further explored. We aimed to employ machine learning (ML) to develop and verify a prediction model of MCI. METHODS: In a longitudinal population-based cohort of China Health and Retirement Longitudinal Study (CHARLS), 8390 non-MCI participants were enrolled. The diagnosis of MCI was based on the aging-associated cognitive decline (AACD), and 13 factors (gender, education, marital status, residence, diabetes, hypertension, depression, hearing impairment, social isolation, physical activity, drinking status, body mass index and expenditure) were finally selected as predictors. We implemented a long short-term memory (LSTM) to predict the MCI risks in middle-aged and older adults within 7 years. The Receiver Operating Characteristic curve (ROC) and calibration curve were used to evaluate the performance of the model. RESULTS: Through 7 years of follow-up, 1925 participants developed MCI. The model for all incident MCI achieved an AUC of 0.774, and its deployment to the participants followed 2, 4, and 7 years achieved results of 0.739, 0.747, and 0.750, respectively. The model was well-calibrated with predicted probabilities plotted against the observed proportions of cognitive impairment. Education level, gender, marital status, and depression contributed most to the prediction of MCI. CONCLUSIONS: This model could be widely applied to medical institutions, even in the community, to identify middle-aged and older adults at high risk of MCI.

Association of High-Density Lipoprotein Cholesterol with Sarcopenia in Chinese Community-Dwelling Middle-Aged and Older Adults: Evidence from 4-Year Longitudinal Study.

INTRODUCTION: There is inconsistent evidence on the associations between high-density lipoprotein cholesterol (HDL-C) and risk of sarcopenia. The aim of the study was to determine the evidence existing between HDL-C and sarcopenia in Chinese middle-aged and older adults. METHODS: We used a panel study design of the China Health and Retirement Longitudinal Study (CHARLS), with 7,415 participants (mean age 57.5 years) from 2011, 2013, and 2015. HDL-C was measured by colorimetric test of venous serum samples. Sarcopenia was defined as low muscle mass, plus low muscle strength, or low physical performance. Muscle mass was estimated by anthropometric measures. Muscle strength was measured by handgrip strength using dynamometer. Physical performance was measured by 5-time chair stand test, gait speed test, and short physical performance battery. RESULTS: With 961 (13.0%) sarcopenia cases, each 1-unit increase (1 SD = 15.4 mg/dL) of HDL-C levels was associated with 42% increased odds of incident sarcopenia (OR = 1.42, 95% confidence interval [CI] = 1.28-1.58) at 4-year follow-up. Females with high HDL-C levels (HDL-C >60 mg/dL) had a higher risk of sarcopenia (OR = 2.49, 95% CI = 1.76-3.52). The restricted cubic spline curves showed a J-shaped association between HDL-C and risk of sarcopenia in females. HDL-C was negatively associated with muscle mass (ß = -0.23, 95% CI = -0.27 to -0.20) and hand grip strength (ß = -0.05, 95% CI = -0.19 to 0.09). CONCLUSION: High HDL-C levels were associated with higher risk of sarcopenia among middle-aged and older Chinese adults, and appropriate control of its high levels informs the management of sarcopenia.

Blood Profiles of Community-Dwelling People with Sarcopenia: Analysis Based on the China Health and Retirement Longitudinal Study.

INTRODUCTION: Routine blood factors can be economical and easily accessible candidates for sarcopenia screening and monitoring. The associations between sarcopenia and routine blood factors remain unclear. This study aimed to examine sarcopenia and blood factor associations based on a nation-wide cohort in China. METHODS: A total of 1,307 participants and 17 routine blood indices were selected from two waves (year 2011 and year 2015) of the China Health and Retirement Longitudinal Study (CHARLS). The diagnosis of sarcopenia was based on the criteria proposed by the Asian Working Group for Sarcopenia (AWGS 2019). Generalized mixed-effects models were performed for association analyses. A logistic regression (LR) model was conducted to examine the predictive power of identifying significant blood factors for sarcopenia. RESULTS: A higher sarcopenia risk was cross-sectionally associated with elevated blood concentrations of high-sensitivity C-reactive protein (hsCRP) (OR = 1.030, 95% CI [1.007, 1.053]), glycated hemoglobin (HbA1c) (OR = 1.407, 95% CI [1.126, 1.758]) and blood urea nitrogen (BUN) (OR = 1.044, 95% CI [1.002, 1.089]), and a decreased level of glucose (OR = 0.988, 95% CI [0.979, 0.997]). A higher baseline hsCRP value (OR = 1.034, 95% CI [1.029, 1.039]) and a greater over time change in hsCRP within 4 years (OR = 1.034, 95% CI [1.029, 1.039]) were associated with a higher sarcopenia risk. A higher BUN baseline value was related to a decreased sarcopenia risk over time (OR = 0.981, 95% CI [0.976, 0.986]), while a greater over time changes in BUN (OR = 1.034, 95% CI [1.029, 1.040]) and a smaller over time change in glucose (OR = 0.992, 95% CI [0.984, 0.999]) within 4 years were also related to a higher sarcopenia risk. LR based on significant blood factors (i.e., hsCRP, HbA1c, BUN, and glucose), and sarcopenia status in year 2015 yielded an area under the curve of 0.859 (95% CI: 0.836-0.882). CONCLUSION: Routine blood factors involved in inflammation, protein metabolism, and glucose metabolism are significantly associated with sarcopenia. In clinical practice, plasma hsCRP, BUN, blood sugar levels, sex, age, marital status, height, and weight might be helpful for sarcopenia evaluation and monitoring.

Cumulative residual cholesterol predicts the risk of cardiovascular disease in the general population aged 45 years and older.

BACKGROUND: Numerous studies have affirmed a robust correlation between residual cholesterol (RC) and the occurrence of cardiovascular disease (CVD). However, the current body of literature fails to adequately address the link between alterations in RC and the occurrence of CVD. Existing studies have focused mainly on individual RC values. Hence, the primary objective of this study is to elucidate the association between the cumulative RC (Cum-RC) and the morbidity of CVD. METHODS: The changes in RC were categorized into a high-level fast-growth group (Class 1) and a low-level slow-growth group (Class 2) by K-means cluster analysis. To investigate the relationship between combined exposure to multiple lipids and CVD risk, a weighted quantile sum (WQS) regression analysis was employed. This analysis involved the calculation of weights for total cholesterol (TC), low-density lipoprotein (LDL), and high-density lipoprotein (HDL), which were used to effectively elucidate the RC. RESULTS: Among the cohort of 5,372 research participants, a considerable proportion of 45.94% consisted of males, with a median age of 58. In the three years of follow-up, 669 participants (12.45%) had CVD. Logistic regression analysis revealed that Class 2 individuals had a significantly reduced risk of developing CVD compared to Class 1. The probability of having CVD increased by 13% for every 1-unit increase in the Cum-RC according to the analysis of continuous variables. The restricted cubic spline (RCS) analysis showed that Cum-RC and CVD risk were linearly related (P for nonlinearity = 0.679). The WQS regression results showed a nonsignificant trend toward an association between the WQS index and CVD incidence but an overall positive trend, with the greatest contribution from TC (weight = 0.652), followed by LDL (weight = 0.348). CONCLUSION: Cum-RC was positively and strongly related to CVD risk, suggesting that in addition to focusing on traditional lipid markers, early intervention in patients with increased RC may further reduce the incidence of CVD.

Triglyceride-glucose index in the prediction of new-onset arthritis in the general population aged over 45: the first longitudinal evidence from CHARLS.

OBJECTIVE: Insulin resistance (IR) imposes a significant burden on inflammatory diseases, and the triglyceride-glucose (TyG) index, which is an easily accessible indicator for detecting IR, holds great application potential in predicting the risk of arthritis. The aim of this study is to analyze the association between the TyG index and the risk of new-onset arthritis in the common population aged over 45 using a prospective cohort study design. METHOD: This population-based cohort study involved 4418 participants from the China Health and Retirement Longitudinal Study (from Wave 1 to Wave 4). Multivariate logistic regression models were employed to investigate the association between the TyG index and new-onset arthritis, and RCS analyses were used to investigate potential non-linear relationships. Moreover, decision trees were utilized to identify high-risk populations for incident arthritis. RESULT: Throughout a 7-year follow-up interval, it was found that 396 participants (8.96%) developed arthritis. The last TyG index quartile group (Q4) presented the highest risk of arthritis (OR, 1.39; 95% CI, 1.01, 1.91). No dose-response relationship between the TyG index and new-onset arthritis was identified (Poverall=0.068, Pnon-linear=0.203). In the stratified analysis, we observed BMI ranging from 18.5 to 24 exhibited a heightened susceptibility to the adverse effects of the TyG index on the risk of developing arthritis (P for interaction = 0.035). CONCLUSION: The TyG index can be used as an independent risk indicator for predicting the start of new-onset arthritis within individuals aged 45 and above within the general population. Improving glucose and lipid metabolism, along with insulin resistance, may play a big part in improving the primary prevention of arthritis.

Association between sleep duration and possible sarcopenia in middle-aged and elderly Chinese individuals: evidence from the China health and retirement longitudinal study.

BACKGROUND: Sarcopenia is a common cause of disability in the aging population, and managing sarcopenia is an important step in building intrinsic capacity and promoting healthy aging. A growing body of evidence suggests that sleep deprivation may be a mediator of the development of sarcopenia. The purpose of this study was to explore the longitudinal association between sleep duration and possible sarcopenia using data from a national sample. METHODS: Two waves of data from the CHARLS database for 2011 and 2015 were used in this study. All possible sarcopenia participants met the Asia Working Group for Sarcopenia 2019 (AWGS 2019) diagnostic criteria. Sleep duration was assessed using a self-report questionnaire, and sleep duration was categorized as short (≤ 6 h), medium (6-8 h), or long (> 8 h) based on previous studies. Longitudinal associations between sleep duration and possible sarcopenia will be calculated by univariate and multifactorial logistic regression analyses and expressed as odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: A total of 5654 individuals participated in the follow-up study, with a prevalence of possible sarcopenia of 53.72% (578) in the short sleep duration group, 38.29% (412) in the medium sleep duration group, and 7.99% (86) in the long sleep duration group. According to the crude model of the second-wave follow-up study, short sleep durations were significantly more strongly associated with possible sarcopenia than were medium and long sleep durations (OR: 1.35, 95% CI: 1.17-1.55, P = 0.000). The association between short sleep duration and possible sarcopenia was maintained even after adjustment for covariates such as age, gender, residence, education level, BMI, smoking status, alcohol consumption and comorbidities (OR: 1.18, 95% CI: 1.02-1.36, P = 0.029). In the subgroup analysis, short sleep duration was associated with low grip strength (OR: 1.20, 95% CI: 1.02-1.41, P = 0.031). CONCLUSIONS: Sleep deprivation may be closely associated with the development of possible sarcopenia in middle-aged and elderly people, which provides new insights and ideas for sarcopenia intervention, and further studies are needed to reveal the underlying mechanisms involved.

Association between obesity, physical activity, and cognitive decline in Chinese middle and old-aged adults: a mediation analysis.

BACKGROUND AND OBJECTIVES: Epidemiological evidence on obesity and cognitive decline in middle and old-aged individuals is controversial and the effect of physical activity in this chain is sparse and limited. This study aimed to characterize the association between obesity and cognitive decline and the mediating role of physical activity. METHODS: Data from China Health and Retirement Longitudinal Study (CHARLS) were used, including 7,392 participants aged ≥ 45 years between 2011 and 2018. Cognitive function was assessed via episodic memory and mental status. The total score of cognitive function was the sum of the above two dimensions (0-31 points). The Group-based trajectory modeling (GBTM) was applied to identify the potential heterogeneity of longitudinal changes in cognitive function. Multivariable ordinal logistic regression was used to investigate associations between obesity and cognitive trajectories, taking body mass index (BMI) as the indicator of obesity. Mediation analysis was performed to examine the potential causal chain in which physical activity mediates the relationship between BMI and cognitive decline. RESULTS: Of the 7,392 analyzed patients (mean [SD] age, 58.0 [8.5] years; 3,916 [53%] male), the median (interquartile range [IQR]) of BMI was 23.4 (21.1-26.0). Four trajectories were identified by the GBTM model, including the high stable (14.9%), the middle stable (46.0%), the middle decline (29.9%), and the low decline groups (9.2%). After controlling potential confounders, obesity was associated with the low decline groups compared with normal weight (adjusted OR 0.81; 95% CI, 0.70-0.94). Mediation analyses showed that only vigorous physical activity significantly explained 5.94% (95% CI, 0.29-11.60%) of the relationship between obesity and cognitive decline. Sensitivity analyses in different subgroups showed comparable results. CONCLUSION: This study suggests that vigorous physical activity mediates less than 10% of the association between obesity and cognitive decline in middle and old-aged adults. Further studies are warranted to explore the potential factors related to the obesity paradox in the cognitive field.

The effects of cognitive leisure activities on frailty transitions in older adults in China: a CHARLS-Based longitudinal study.

BACKGROUND: In an effort to identify factors associated with frailty transitions that trigger a significant difference in preventing and postponing the progression of frailty, questions regarding the role of cognitive leisure activities on various aspects of older adults' health were raised. However, the relationship between cognitive leisure activities and frailty transitions has rarely been studied. METHODS: A total of 5367 older Chinese adults aged over 60 years from the China Health and Retirement Longitudinal Study (CHARLS) were selected as participants. The 2nd wave of the CHARLS in 2013 was selected as the baseline, and sociodemographic and health-related status baseline data were collected. The FRAIL Scale was used to measure frailty, while cognitive leisure activities were measured by the Cognitive Leisure Activity Index (CLAI) scores, which consisted of playing mahjong or cards, stock investment, and using the internet. After two years of follow-up, frailty transition from baseline was assessed at the 3rd wave of the CHARLS in 2015. Ordinal logistic regression analysis was used to examine the relationship between cognitive leisure activities and frailty transitions. RESULTS: During the two-year follow-up of 5367 participants, the prevalence of frailty that improved, remained the same and worsened was 17.8% (957/5367), 57.5% (3084/5367) and 24.7% (1326/5367), respectively. Among all participants, 79.7% (4276/5367), 19.6% (1054/5367), and 0.7% (37/5367) had CLAI scores of 0, 1, and 2 to 3, respectively. In the univariate analysis, there was a statistically significant association between a score of 2 to 3 on the Cognitive Leisure Activity Index and frailty transitions (odds ratio [OR] = 1.93, 95% CI 0.03 to 1.29, p = .04), while all other covariates were not significantly different across the three groups. After adjusting for covariates, participants with more cognitive leisure activities had a higher risk of frailty improvement than those without cognitive leisure activities (odds ratio [OR] = 1.99, 95% CI 1.05 to 3.76, p = .04). CONCLUSIONS: Cognitive leisure activities were positively associated with the risk of frailty improvement in older adults, mainly when participating in multiple such activities. Older adults may be encouraged to participate in a wide variety of cognitive leisure activities to promote healthy aging.

U-shaped relationship between non-high-density lipoprotein cholesterol and cognitive impairment in Chinese middle-aged and elderly: a cross-sectional study.

BACKGROUND: The relationship between blood lipids and cognitive function has long been a subject of interest, and the association between serum non-high-density lipoprotein cholesterol (non-HDL-C) levels and cognitive impairment remains contentious. METHODS: We utilized data from the 2011 CHARLS national baseline survey, which after screening, included a final sample of 10,982 participants. Cognitive function was assessed using tests of episodic memory and cognitive intactness. We used multiple logistic regression models to estimate the relationship between non-HDL-C and cognitive impairment. Subsequently, utilizing regression analysis results from fully adjusted models, we explored the nonlinear relationship between non-HDL-C as well as cognitive impairment using smooth curve fitting and sought potential inflection points through saturation threshold effect analysis. RESULTS: The results showed that each unit increase in non-HDL-C levels was associated with a 5.5% reduction in the odds of cognitive impairment (OR = 0.945, 95% CI: 0.897-0.996; p < 0.05). When non-HDL-C was used as a categorical variable, the results showed that or each unit increase in non-HDL-C levels, the odds of cognitive impairment were reduced by 14.2%, 20.9%, and 24% in the Q2, Q3, and Q4 groups, respectively, compared with Q1. In addition, in the fully adjusted model, analysis of the potential nonlinear relationship by smoothed curve fitting and saturation threshold effects revealed a U-shaped relationship between non-HDL-C and the risk of cognitive impairment, with an inflection point of 4.83. Before the inflection point, each unit increase in non-HDL-C levels was associated with a 12.3% decrease in the odds of cognitive impairment. After the tipping point, each unit increase in non-HDL-C levels was associated with an 18.8% increase in the odds of cognitive impairment (All p < 0.05). CONCLUSION: There exists a U-shaped relationship between non-HDL-C and the risk of cognitive impairment in Chinese middle-aged and elderly individuals, with statistical significance on both sides of the turning points. This suggests that both lower and higher levels of serum non-high-density lipoprotein cholesterol increase the risk of cognitive impairment in middle-aged and elderly individuals.

The mediating role of children's intergenerational support in association between grandparenting and cognitive function among middle-aged and older Chinese: findings from the CHARLS cohort study.

OBJECTIVES: With the world's population increasing in age, there has been a significant rise in the prevalence of cognitive impairment and dementia among individuals. This study aims to investigate the association between grandparenting and cognitive function among middle-aged and older Chinese using data from 2011 to 2018 China Health and Retirement Longitudinal Study (CHARLS). Additionally, the study seeks to explore the potential mediating effect of intergenerational support from children on this relationship, using data from the CHARLS 2011 database. METHODS: 5254 participants were recruited at the baseline survey in CHARLS 2011. Subsequently, a follow-up survey was conducted over 8 years, from CHARLS 2011 to 2018, with 1472 individuals completing the follow-up survey. The CHARLS included surveys on grandparenting and cognitive assessments. Grandparenting was categorized as yes and no. The assessment of cognitive function involved the evaluation of episodic memory and mental intactness. The present study used cross-sectional and longitudinal analyses to examine the relationship between grandparenting and cognitive function. The bootstrap method assessed the mediating effect of children's intergenerational support. RESULTS: The results of both cross-sectional and longitudinal studies indicated a positive association between grandparenting and cognitive function in middle-aged and older Chinese (B = 0.138, p < 0.05; B = 0.218, p < 0.05). Children's emotional and economic support played intermediary roles between grandparenting and cognitive function. CONCLUSION: The results emphasized the significance of policymakers considering the consequences of intergenerational care and family support when formulating and executing social service policies targeted at the middle-aged and older population in China.