Association between Triglyceride-glucose index and carotid artery plaque in young and middle-aged occupational population

Background: China has the world’s highest rail transportation density, and the health of railway workers, therefore, deserves public attention. The triglyceride glucose (TyG) index has been proposed as a surrogate indicator of insulin resistance. However, there are limited studies on the association between the TyG index and carotid artery plaque (CAP) in railway workers. Methods: This cross-sectional study was conducted among southwest China railway workers. 3,169 workers were divided into four groups according to TyG index quartiles. The CAP was assessed by carotid doppler ultrasound. Logistic regression and restricted cubic spline were used to estimate the association between TyG index and CAP, and subgroup analysis was performed by age, blood pressure, metabolic dysfunction-associated fatty liver disease (MAFLD), smoking, drinking, and physical activity. Results: Compared with participants in the lowest quartile, those with high TyG index quartiles were more likely to have a higher prevalence of CAP, with 11.63%, 14.11%, 20.20% and 18.56% from quartile 1 st [Q1] to quartile 4 th [Q4]. When the TyG index was treated as a continuous variable, the multi-adjusted logistic regression models showed that the TyG index was positively associated with the risk of CAP (OR: 1.26, 95% CI: 1.08,1.47). With increasing TyG index tertiles, TyG index as a categorical variable, the risk of CAP increased substantially with ORs (95% CIs) of 1.24 (0.92,1.69) for Q2, 1.78 (1.32,2.41) for Q3, 1.56 (1.14,2.15) for Q4 compared with the lowest quartile of TyG index. Conclusion: The TyG index, especially in high quartiles, was associated with CAP in the railway workers. Monitoring the TyG index was a good risk management strategy of CAP.