Abstract
Abdominal aortic calcification (AAC) is a well-established predictor of cardiovascular morbidity and mortality. Although insulin resistance (IR) is implicated in vascular calcification, evidence on the association between IR surrogates and severe AAC remains limited. A cross-sectional analysis of 1230 participants was conducted using data from the 2013 to 2014 National Health and Nutrition Examination Survey (NHANES). Multiple regression and generalized additive models (GAM) were employed to evaluate the associations between IR surrogates (TyG index, homeostasis model assessment of insulin resistance (HOMA-IR), and METS-IR) and severe AAC. The predictive performance of the triglyceride glucose (TyG) index and its derived indicators in predicting severe AAC was assessed using receiver operating characteristic (ROC) curves and the area under the curve (AUC). Multiple regression analysis revealed a positive association between TyG index (calculated from fasting triglyceride and glucose levels) and severe AAC risk (OR = 1.642, 95% CI: 1.050, 2.570, P = .030) after adjusting for confounders. This association persisted even after adjusting for metabolic syndrome and log (HOMA-IR). Trend tests and GAM confirmed a linear dose-response relationship between the TyG index and severe AAC. Subgroup analysis revealed that this relationship was stronger in women. ROC and AUC analyses demonstrated that the TyG index could reliably predict severe AAC (AUC = 0.858). No significant association was found between HOMA-IR, METS-IR, and severe AAC. An elevated TyG index was associated with an increased risk of severe AAC, independent of metabolic syndrome. These findings underscore the critical importance of managing the TyG index to reduce the risk of severe AAC and have important implications for clinical practice and epidemiological studies.