Association of the triglyceride-glucose index and phlegm-dampness constitution with subclinical carotid atherosclerosis in overweight and obese individuals.

OBJECTIVE: This study aims to investigate the association between the triglyceride-glucose (TyG) index and Phlegm-dampness constitution (PDC), as well as their joint association, on subclinical carotid atherosclerosis (SCAS) in an overweight and obese population. METHODS: In this cross-sectional study, 217 overweight or obese participants were enrolled. The TyG index was categorized at the median into high and low TyG groups, and a four-category joint exposure variable was developed based on PDC status. Multivariable logistic regression was employed to assess the relationship between joint exposure and SCAS, with a stratified analysis conducted by PDC. RESULTS: SCAS was identified in 67 of 217 participants (30.9%). The TyG index (AUC 0.681) demonstrated superior performance compared to HOMA-IR (0.585) and BMI (0.515) in distinguishing SCAS. The AUC increased from 0.704 (base model: age, sex, BMI) to 0.779 after adding the TyG index (DeLong P = 0.005) and remained essentially unchanged after further adding PDC (0.783, DeLong P = 0.220). Among the four groups, the highest prevalence of SCAS was noted in the high TyG/PDC group (50.0%), while the lowest prevalence occurred in the low TyG/PDC group (12.0%). After adjusting for age, sex, and BMI, the odds of SCAS were significantly increased in the high TyG/PDC group (OR=4.83, 95% CI: 1.67-13.95). In stratified analysis, the TyG-SCAS association was numerically stronger in the PDC subgroup (OR=11.81) than in the non-PDC subgroup (OR=2.88), although the interaction was not significant (P = 0.252). CONCLUSION: The coexistence of a high TyG index and PDC was associated with markedly higher odds of SCAS. The finding that the TyG-SCAS association appeared stronger in the PDC subgroup is exploratory and requires validation in larger prospective studies.