Association of inflammatory biomarkers and pericoronary fat attenuation index with coronary functional ischemia in patients with metabolic dysfunction-associated fatty liver disease

Patients with metabolic dysfunction-associated fatty liver disease (MAFLD) and coronary heart disease (CHD) exhibit systemic and coronary inflammation. However, the value of integrating systemic inflammatory biomarkers and the pericoronary fat attenuation index (FAI) for identifying functional coronary ischemia remains unclear. This study aimed to identify factors associated with functional coronary ischemia and to develop an exploratory risk stratification tool. A total of 261 consecutive patients with MAFLD and CHD were retrospectively enrolled between June 2019 and July 2025. Patients were divided according to computed tomography-derived fractional flow reserve (CT-FFR) values into CT-FFR > 0.80 and CT-FFR ≤ 0.80 groups. Least absolute shrinkage and selection operator (LASSO) regression and multivariable logistic regression were performed to identify independent factors associated with the outcome and to construct a nomogram. Model performance was evaluated using receiver operating characteristic (ROC) curves, calibration curves, decision curve analysis (DCA), and clinical impact curves (CIC), with nested internal validation that repeated the entire model-building process in each resample. LASSO regression retained 10 variables. In multivariable analysis, hypertension, alanine aminotransferase (ALT), low-density lipoprotein cholesterol (LDL-C), white blood cell count (WBC), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), FAI, and triglycerides (TG) were independent risk factors and high-density lipoprotein cholesterol (HDL-C) was protective ( P < 0.05). The nomogram showed good discrimination (apparent AUC = 0.9146, 95% CI: 0.8825–0.9466; nested optimism-corrected AUC 0.8874; nested 10-fold cross-validated AUC 0.8711) and no evidence of miscalibration in the development sample. Systemic inflammatory biomarkers combined with FAI are independently associated with CT-FFR-defined functional coronary ischemia in patients with MAFLD and CHD. The resulting nomogram is an exploratory risk stratification tool that requires external, prospective multicenter validation before any clinical application.