Objective To investigate the association between the triglyceride-glucose (TyG) index and the occurrence of carotid atherosclerotic plaque (CAP) in a population with varying characteristics.

Methods A total of 1, 019 residents from Liuzhou City, Guangxi Zhuang Autonomous Region, who met the inclusion and exclusion criteria between 2019 and 2023, were selected as study participants. General data and laboratory biochemical indices of the participants were collected, and they were categorized into 309 cases in the CAP group and 710 cases in the normal group based on carotid ultrasound results. The correlation between the TyG index and the occurrence of CAP in the population with varying characteristics was analyzed using LASSO regression, multifactorial logistic regression, and linear trend tests.

Results LASSO regression identified eight variables to construct the subgroups for analysis: age, smoking, hypertension, low-density lipoprotein cholesterol (LDL-C), body mass index (BMI), high-density lipoprotein cholesterol (HDL-C), sex, and drinking. Subgroup analysis results indicated an association between the TyG index and the occurrence of CAP in individuals under 60 years of age, those with drinking, and those who were overweight or obese. Furthermore, an interaction was observed between the TyG index and factors such as drinking, overweight or obesity. The results of multivariate logistic regression showed that, after adjusting for confounders, the occurrence of CAP was 2.118 and 2.408 times higher at Level 3 and Level 4 of the TyG index, respectively, compared with the Level 1 of TyG index in overweight or obese populations (P < 0.05). Moreover, the results of the linear trend test revealed a linear relationship between the TyG index and CAP (P_trend < 0.05).

Conclusion There is a positive correlation between the TyG index and CAP among overweight or obese individuals, suggesting that this group may be the key population for using the TyG index to evaluate the occurrence of CAP.