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.