Reduced Predictive Performance of the FIB-4 Index in Chronic Hepatitis B Patients With Concurrent Metabolic Dysfunction-Associated Liver Disease

The coexistence of chronic hepatitis B (CHB) and metabolic dysfunction–associated liver disease (MASLD) gained recognition, but the diagnostic performance of non-invasive markers regarding it remains underexplored. This study aimed to evaluate the utility of the FIB-4 index for fibrosis prediction in CHB patients and investigate its performance in the distinct subgroup of CHB-MASLD. A prospective study from 2021 to 2022 included 109 CHB and 64 CHB-MASLD patients. All underwent liver stiffness measurement via elastography and FIB-4 calculation. MASLD criteria were defined, creating CHB-alone and CHB-MASLD groups. FIB-4 values were compared to the liver stiffness measurements. Statistical analyses included t-tests, ROC curves, and correlation assessments. No significant age, gender, or ethnicity differences were observed between the CHB and CHB-MASLD groups. CHB-MASLD patients exhibited higher BMI, dysglycemia, and dyslipidemia. HBeAg negativity and nucleoside/tide treatment rates were comparable. FIB-4 and APRI scores were elevated in CHB-MASLD. ROC analysis revealed an AUC of 0.86 for FIB-4 in the CHB group, with an optimal cutoff of 1.95. Subgroup analysis by BMI showed consistent FIB-4 performance. In the CHB-MASLD group, the ROC curve showed an AUC of 0.61 (p = 0.12), indicating non-significance. Our study affirms FIB-4's robust performance in predicting fibrosis in CHB patients across varied BMI profiles. Yet, challenges surface when applying FIB-4 to those with concurrent CHB and MASLD. These limitations stress the urgency of refined fibrosis prediction tools, essential for navigating the complex interplay of viral and metabolic factors in the CHB–MASLD population.