Association between triglyceride-glucose index and carotid atherosclerosis detected by ultrasonography.

BACKGROUND: Several previous studies have indicated that the triglyceride-glucose index (TyG) index is associated with carotid atherosclerosis (CA); however, the evidence of the association is limited and inconsistent, which may result from small sample sizes or differences in study populations. Therefore, we examined the relation between the TyG index and CA in a large general population of Chinese middle-aged and elderly population. METHODS: A total of 59,123 middle-aged and elderly participants were enrolled. The TyG index was calculated as ln[fasting triglycerides (mg/dL)×fasting glucose (mg/dL)/2]. Logistic regression models were used to analyze the relationship between the TyG index as continuous variables and quartiles and CA. The relationships between the TyG index and CA according to sex, age groups, blood pressure groups and body mass index groups were also assessed. RESULTS: The multivariate logistic regression analysis showed that the TyG index was significantly associated with the prevalence of CA (OR: 1.48; 95% CI 1.39-1.56), carotid intima-media thickness (CMT) (1.55; 1.45-1.67), plaques (1.38; 1.30-1.47) and stenosis severity (> 50%) (1.33; 1.14-1.56). Compared with the quartile 1, quartile 4 was significantly associated with a higher prevalence of CA (1.59; 1.45-1.75), CMT (1.93; 1.82-2.18), plaques (1.36; 1.22-1.51) and stenosis severity (> 50%) (1.56; 1.20-2.04). Subgroup analyses showed significant associations between the continuous TyG index and the prevalence of CA, CMT, plaques and stenosis severity (> 50%) according to sex, with a higher prevalence of CA, CMT, and plaques among males, while a higher prevalence of stenosis severity in females (> 50%). For participants aged < 60 years old and with hypertension, the relationship between the TyG index and stenosis severity (> 50%) was not observed (1.47; 0.97-2.22 and 1.13; 0.91-1.41). For body mass index (BMI), the association was just observed among overweight participants (1.48; 1.17-1.86). In addition, similar results were also observed when the TyG index was used as a categorical variable. CONCLUSIONS: There is a positive association between the TyG index and CA. The association is higher in males and middle-aged individuals than those in females and elderly individuals. Besides, the relationship is stronger among individuals with normal blood pressure and underweight subjects.