Counterintuitive relationship between the triglyceride glucose index and diabetic foot in diabetes patients: A cross-sectional study

Abstract

Background Research has shown that insulin resistance (IR) is a known risk factor for diabetic foot (DF), and the triglyceride-glucose (TyG) index is a reliable and simple indicator of IR. However, less is known about the relationship between the TyG and the risk of DF. Here, we investigated the association between the TyG index and the prevalence of DF. Methods The eligible records from the Departments of Endocrinology of Shandong Provincial Hospital Affiliated to Shandong First Medical University were screened (from December 1, 2012, to December 31, 2021), and a total of 8866 patients were enrolled. The TyG index was calculated as ln[(fasting triglycerides (mg/dL)×fasting glucose (mg/dL)/2)]. The continuous variables between the DF and the non-DF groups were compared by Student’s t test or the Mann-Whitney U test, and categorical variables were compared by the chi-square test. Receiver operating characteristic curve (ROC) analysis was carried out to estimate the predictive value of the TyG index for DF. Logistic regression models were used to evaluate the associations between the quartiles of the TyG index and the risk of DF. Subgroup and sensitivity analyses were conducted. Results The TyG index was significantly lower in the DF group than in the no-DF group. The logistic regression revealed that an increased TyG index was associated with a lower risk of DF after adjusting for potential confounders. In addition, an ROC analysis indicated the discriminatory ability of the TyG index in DF presence with an area under the curve (AUC) of 0.661 (95% CI 0.642–0.680, P < 0.001). Subgroup and sensitivity analysis also supported these robust results. Conclusions The TyG index was inversely and dose-dependently associated with the risk of DF in diabetes patients, indicating that elevated TyG index was a protective factor for DF. Future studies are therefore warranted to confirm our finding and to explore the detailed pathological mechanism involved in this process.