Background: The Triglyceride-glucose (TyG) index, as a surrogate marker of insulin resistance, is independently associated with the severity of coronary artery lesions and the prognosis of coronary heart disease. The investigation aimed to explore the relationship between the TyG index and recurrent revascularization in individuals with type 2 diabetes mellitus (T2DM) resulting from the progression of lesions or in-stent restenosis (ISR) after percutaneous coronary intervention (PCI). Method: A total of 633 patients who met the inclusion and exclusion criteria were enrolled and divided into three groups based on the tertiles of the TyG index. The primary endpoint was recurrent revascularization resulting from the progression of lesions or ISR. All-cause death was considered as the competing risk event. Competing risk analysis and Cox regression analysis for predicting recurrent revascularization after PCI were conducted stepwise. Variables were standardized to make the hazard ratio (HR), subdistribution hazard ratio (SHR) and corresponding 95% CI more consistent prior to being used for fitting the multivariate risk model. The predictive ability of the TyG index was evaluated using several measures, including the ROC curve, likelihood ratio test, Akaike’s information criteria, category-free continuous net reclassification improvement (cNRI > 0), and integrated discrimination improvement (IDI). Internal validation was conducted through bootstrapping with 1000 resamples. Results: During a median follow-up period of 18.33 months, a total of 64 (10.11%) patients experienced recurrent revascularization, including 55 cases of lesion progression and 9 cases of in-stent restenosis. After controlling for competitive risk events, the TyG index was independently associated with a higher risk of recurrent revascularization [SHR:1.4345, (95% CI 1.1458–1.7959), P = 0.002]. The likelihood ratio test and Akaike’s information criteria showed that the TyG index significantly improves the prognostic ability. Additionally, adding the TyG index improved the ability of the established risk model in predicting recurrent revascularization, indicated by a C-index of 0.759 (95% CI 0.724–0.792, P < 0.01), with a cNRI > 0 of 0.170 (95% CI 0.023–0.287, P < 0.05), and an IDI of 0.024 (95% CI 0.009–0.039, P = 0.002). These results remained consistent when the models containing TyG index were confirmed using an internal bootstrap validation method. Conclusion: The findings highlight the potential of the TyG index as a predictor of recurrent revascularization. Lesion progression emerged as the primary contributor to recurrent revascularization instead of in-stent restenosis. The incorporation of the TyG index into risk prediction models is likely to be beneficial for accurate risk stratification in order to improve prognosis.

Nutritional status is associated with prognosis in acute coronary syndrome (ACS) patients. Although the Global Registry of Acute Coronary Events (GRACE) risk score is regarded as a relevant risk predictor for the prognosis of ACS patients, nutritional variables are not included in the GRACE score. This study aimed to compare the prognostic ability of the Geriatric Nutritional Risk Index (GNRI) and Prognostic Nutritional Index (PNI) in predicting long-term all-cause death in ACS patients undergoing percutaneous coronary intervention (PCI) and to determine whether the GNRI or PNI could improve the predictive value of the GRACE score. A total of 799 patients with ACS who underwent PCI from May 2018 to December 2019 were included and regularly followed up. The performance of the PNI in predicting all-cause death was better than that of the GNRI [C-index, 0.677 vs. 0.638, p = 0.038]. The addition of the PNI significantly improved the predictive value of the GRACE score for all-cause death [increase in C-index from 0.722 to 0.740; IDI 0.006; NRI 0.095; p < 0.05]. The PNI was superior to the GNRI in predicting long-term all-cause death in ACS patients undergoing PCI. The addition of the PNI to the GRACE score could significantly improve the prediction of long-term all-cause death.

Background: Despite percutaneous coronary intervention (PCI) for revascularization, patients with acute coronary syndrome (ACS) still face residual risks of adverse outcomes. Insulin resistance (IR) and renal impairment are independent predictors of poor prognosis in these patients, yet their interaction and underlying mechanisms linked to post-PCI outcomes remain incompletely elucidated. Methods: A retrospective cohort study was conducted involving patients with ACS who underwent PCI at the Third People’s Hospital of Chengdu from July 2018 to December 2020. Insulin resistance (IR) was quantified using the triglyceride–glucose (TyG) index, and renal function was evaluated via the estimated glomerular filtration rate (eGFR). The primary endpoint was major adverse cardiovascular events (MACEs), a composite of all-cause death, non-fatal myocardial infarction, non-fatal stroke, and unplanned revascularization. Multivariable Cox proportional hazards regression and mediation analyses were applied to explore the associations of TyG index and eGFR with patient prognosis, and to quantify the mediating effect of eGFR on the relationship between TyG index and prognosis. Results: A total of 1340 patients with ACS were included in the final analysis. Over a median follow-up duration of 31.02 (interquartile range [IQR]: 27.34–35.03) months, 124 patients (9.25%) experienced MACEs. After adjusting for potential confounders, both the TyG index and eGFR were identified as significant independent predictors of MACEs in the overall population and across predefined subgroups. Specifically, each one-unit increase in the TyG index was associated with a 73.8% higher risk of MACEs (HR 1.738; 95% CI 1.273–2.372), whereas each ten-unit decrease in eGFR was linked to a 12.7% increased MACEs risk (HR 1.127; 95% CI 1.032–1.232). Importantly, after further adjustment for confounders, eGFR significantly mediated 9.63% of the total effect of the TyG index on MACEs risk. Conclusions: Renal impairment partially mediates the association between IR and adverse cardiovascular outcomes in ACS patients undergoing PCI. This finding underscores the clinical importance of the metabolic–cardiorenal axis in this population, suggesting that a comprehensive assessment targeting both IR and renal function-related pathways may enhance risk-stratification accuracy and optimize therapeutic strategies for ACS patients.