Background: Cardiovascular disease (CVD) is closely associated with the triglyceride glucose (TyG) index and its related indicators, particularly its combination with obesity indices. However, there is limited research on the relationship between changes in TyG-related indices and CVD, as most studies have focused on baseline TyG-related indices. Methods: The data for this prospective cohort study were obtained from the China Health and Retirement Longitudinal Study. The exposures were changes in TyG-related indices and cumulative TyG-related indices from 2012 to 2015. The K-means algorithm was used to classify changes in each TyG-related index into four classes (Class 1 to Class 4). Multivariate logistic regressions were used to evaluate the associations between the changes in TyG-related indices and the incidence of CVD. Results: In total, 3243 participants were included in this study, of whom 1761 (54.4%) were female, with a mean age of 57.62 years at baseline. Over a 5-year follow-up, 637 (19.6%) participants developed CVD. Fully adjusted logistic regression analyses revealed significant positive associations between changes in TyG-related indices, cumulative TyG-related indices and the incidence of CVD. Among these changes in TyG-related indices, changes in TyG-waist circumference (WC) showed the strongest association with incident CVD. Compared to the participants in Class 1 of changes in TyG-WC, the odds ratio (OR) for participants in Class 2 was 1.41 (95% confidence interval (CI) 1.08–1.84), the OR for participants in Class 3 was 1.54 (95% CI 1.15–2.07), and the OR for participants in Class 4 was 1.94 (95% CI 1.34–2.80). Moreover, cumulative TyG-WC exhibited the strongest association with incident CVD among cumulative TyG-related indices. Compared to the participants in Quartile 1 of cumulative TyG-WC, the OR for participants in Quartile 2 was 1.33 (95% CI 1.00–1.76), the OR for participants in Quartile 3 was 1.46 (95% CI 1.09–1.96), and the OR for participants in Quartile 4 was 1.79 (95% CI 1.30–2.47). Conclusions: Changes in TyG-related indices are independently associated with the risk of CVD. Changes in TyG-WC are expected to become more effective indicators for identifying individuals at a heightened risk of CVD.

Background: Frailty is a common characteristic of older people with the ageing process. We aimed to develop and validate a dynamic statistical prediction model to calculate the risk of death in people aged ≥65 years, using a longitudinal frailty index (FI). Methods: One training dataset and three validation datasets from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) were used in our study. The training dataset and validation datasets 1 to 3 included data from 9,748, 7,459, 9,093 and 6,368 individuals, respectively. We used 35 health deficits to construct the FI and a longitudinal FI based on repeated measurement of FI at every wave of the CLHLS. A joint model was used to build a dynamic prediction model considering both baseline covariates and the longitudinal FI. Areas under time-dependent receiver operating characteristic curves (AUCs) and calibration curves were employed to assess the predictive performance of the model. Results: A linear mixed-effects model used time, sex, residence (city, town, or rural), living alone, smoking and alcohol consumption to calculate a subject-specific longitudinal FI. The dynamic prediction model was built using the longitudinal FI, age, residence, sex and an FI–age interaction term. The AUCs ranged from 0.64 to 0.84, and both the AUCs and the calibration curves showed good predictive ability. Conclusions: We developed a dynamic prediction model that was able to update predictions of the risk of death as updated measurements of FI became available. This model could be used to estimate the risk of death in individuals aged >65 years.

Objectives Frailty is a state of decreased resilience when a person is exposed to an apparently innocuous stressor that is associated with numerous adverse outcomes. The aim is to examine frailty prevalence in China by demographic and investigate the correlation between frailty and outcome. Design Cohort study. Setting Community-dwelling adults from 28 Chinese provinces. Methods The participants were 2,273 adults aged ≥65 years from the China Health and Retirement Longitudinal Study. Frailty was scored on the FRAIL scale. We estimated frailty prevalence in the overall sample. The association of frailty with adverse outcomes was evaluated by multinomial logistic regression analysis. Results We found that 17.0% of adults aged ≥65 years were frail. Frail individuals had a higher prevalence of comorbidities, falls, and need for medical care than non-frail individuals. The multinomial logistic regression analysis demonstrated that frail status (OR = 2.061, 95% CI: 1.422–2.985) and pre-frail status (OR = 1.540, 95% CI: 1.135–2.089) were associated with falls in the previous two years. Serious falls in the previous two years were related to pre-frailty (OR = 1.815, 95% CI: 1.153–2.859) and frailty (OR = 2.797, 95% CI: 1.655–4.727). In addition, frail individuals were found to be at higher risk for outpatient visits over the previous month (OR = 2.091, 95% CI: 1.502–2.911) and readmission over the previous year (OR = 2.033, 95% CI: 1.480–2.792) in the analysis. Conclusions Pre-frailty and frailty were positively associated with major adverse outcomes, including falls and serious falls; they were also associated with more frequent outpatient visits and readmissions in the past.