Quantifying the metabolic-inflammatory axis: synergistic value of TyG index and FAI in assessing CAD risk among MAFLD patients

Background: This study evaluated coronary inflammation and insulin resistance (IR) using pericoronary fat attenuation index (FAI) and triglyceride-glucose (TyG) index, and assessed their associations with coronary heart disease (CHD) and functional ischemia in patients with metabolic dysfunction-associated fatty liver disease (MAFLD). Methods: A total of 435 patients (174 MAFLD, 261 MAFLD+CHD) were included. The MAFLD+CHD group was stratified by CT-derived fractional flow reserve (CT-FFR) into >0.80 and ≤0.80 subgroups. FAI and CT-FFR were automatically calculated using AI-based software; Independent risk factors were identified using multivariable logistic regression analysis, based on which a nomogram was constructed. The predictive performance of the nomogram was evaluated using ROC curves, calibration curves, and decision curve analysis (DCA), with internal validation performed via the Bootstrap method. The predictive accuracy of the nomogram was also compared with that of FAI and the TyG index. Restricted cubic spline (RCS) models were employed to explore the potential nonlinear relationship between the TyG index and FAI, as well as the dose-response associations of these indices with disease risk. Results: Multivariate logistic regression showed that TyG index and FAI were independent risk factors for CHD and coronary functional ischemia (P