TyG Index Shows Strong Association with Microcirculatory Resistance in Diabetic STEMI Patients Post-PCI: Study

The research suggests that the TyG index, a simple yet effective marker of insulin resistance, could be a valuable predictor of elevated AMR in this cohort.

AMR, a key factor influencing coronary microvascular dysfunction, has long been associated with poor outcomes in STEMI patients. In patients with T2DM, the presence of microvascular damage complicates the treatment and recovery process, potentially leading to a worse prognosis following pPCI. The TyG index, calculated using fasting triglyceride and glucose levels, is increasingly recognized as a marker for assessing insulin resistance and metabolic dysfunction.

Against the above background, Li Zhu, Department of Cardiology, The Affiliated Taizhou People’s Hospital of Nanjing Medical University, Taizhou, Jiangsu, People’s Republic of China, and colleagues aimed to investigate the relationship between the TyG index and the AMR in patients with type 2 diabetes mellitus and ST-segment elevation myocardial infarction.

For this purpose, the researchers consecutively recruited 168 patients with type 2 diabetes mellitus and STEMI who underwent primary percutaneous coronary intervention at Taizhou People’s Hospital between January 2022 and December 2023. The patients were divided into two groups based on their microcirculatory resistance: a low AMR group (AMR < 2.5) and a high AMR group (AMR ≥ 2.5). The TyG index was calculated using the following formula: ln [plasma triglyceride (mg/dL) × fasting blood glucose (mg/dL)/2].

The study led to the following findings:

• The study included 81 patients in the low AMR group and 87 in the high AMR group, with the TyG index significantly higher in the high AMR group.
• Multivariable logistic regression analysis showed a significant association between the TyG index and high AMR after adjusting for confounding factors (odds ratio: 2.449).
• The area under the curve (AUC) for the TyG index in predicting high AMR was 0.650, with a cut-off value of 9.57.

The researchers acknowledged several limitations in their study. It was a single-center, retrospective analysis, which could introduce selection bias and limit the generalizability of the findings. Additionally, the small sample size constrained the statistical power to detect subtle associations. The measurement of AMR using a single angiographic view, though validated, may also limit the accuracy of the results.

The researchers further noted, "Fluctuations in triglyceride and fasting blood glucose levels during hospitalization or follow-up were not assessed, which could influence microcirculatory resistance. While the TyG index is convenient for clinical use, it is less specific than direct insulin measurement methods."

They concluded, "Although the TyG index appears linked to microcirculatory resistance in diabetic STEMI patients, further research in larger, more diverse cohorts is needed to confirm these findings and explore the mechanisms underlying insulin resistance and microcirculatory dysfunction."

Reference:

Wang, G., Xu, C., Wang, J., Teng, Z., Sha, X., Xu, K., Wang, R., & Zhu, L. (2025). Triglyceride-glucose index is associated with microcirculatory resistance in patients with type 2 diabetes and STEMI undergoing primary PCI. Scientific Reports, 15(1), 1-9. https://doi.org/10.1038/s41598-025-89269-6