Joint Associations of Cumulative Triglyceride-Glucose-A Body Shape Index and Frailty Trajectories With Incident Cardiovascular Disease in Middle-Aged and Older Chinese Adults.

Higher cumulative TyG-ABSI was independently associated with higher risk of incident CVD in middle-aged and older Chinese adults.

• Each 1-SD increase in cumulative TyG-ABSI was associated with higher CVD risk (HR 1.16, 95% CI 1.06-1.26).
• Cumulative TyG-ABSI was calculated as the mean of fasting measurements in 2011 and 2015.
• Among 3026 participants, 606 met the study definition of incident CVD.

Membership in the higher frailty trajectory was independently associated with greater incident CVD risk.

• The higher frailty trajectory had an HR of 1.91 (95% CI 1.53-2.39).
• Frailty trajectories were identified from frailty-index measurements in 2011, 2013, and 2015 using latent class linear mixed models.

Joint classification by cumulative TyG-ABSI and frailty trajectory showed a graded gradient of CVD risk.

• Relative to low TyG-ABSI/lower frailty, HRs were 1.26 (95% CI 1.04-1.53) for high TyG-ABSI/lower frailty.
• The HR was 1.87 (95% CI 1.34-2.61) for low TyG-ABSI/higher frailty.
• The HR was 2.43 (95% CI 1.79-3.29) for high TyG-ABSI/higher frailty.

No statistically significant multiplicative or additive interaction was found between cumulative TyG-ABSI and frailty trajectory.

• Multiplicative and additive interactions were not significant.
• The joint pattern was described as a cumulative risk gradient without statistical synergy.

The study used discrete-time survival modeling because exact CVD onset dates were unavailable, and the outcome was survey-ascertained.

• Data came from the China Health and Retirement Longitudinal Study.
• Incident CVD was a newly reported physician diagnosis of heart disease or stroke in 2018 or 2020.
• Complementary log-log discrete-time survival models with cluster-robust standard errors were used.

The authors conclude the findings support complementary risk stratification but not a validated clinical threshold or causal effect.

• The findings are observational.
• The outcome was survey-ascertained rather than clinically adjudicated.