Prognostic Value of the FIB-3 Index in Patients With Hepatic Encephalopathy Receiving Rifaximin: A Multicenter Retrospective Analysis.

AIMS: This study investigated the prognostic performance of the FIB-3 index, composed of aspartate aminotransferase, alanine aminotransferase, and platelet count, in patients with decompensated cirrhosis and overt hepatic encephalopathy receiving rifaximin therapy. METHODS: Between March 2017 and March 2024, 235 patients were included in this multicenter retrospective study. The discriminatory performance of the FIB-3 index for predicting 48-month survival was compared with that of the FIB-4 index, aMAP score, MELD 3.0 score, and Child-Pugh classification. RESULTS: The AUROCs for the FIB-3 index, FIB-4 index, aMAP score, MELD 3.0 score, and Child-Pugh classification were 0.63, 0.58, 0.57, 0.71, and 0.70, respectively. Using the FIB-3 index as the reference model, no statistically significant differences in AUROC were observed between the FIB-3 index and the other models (p = 0.05, 0.2, 0.1, and 0.1, respectively). In the NRI analysis, the FIB-3 index demonstrated significantly better discriminatory performance than the FIB-4 index (p < 0.001) but poorer discriminatory performance than Child-Pugh classification (p < 0.001), whereas no significant differences were observed compared with the aMAP or MELD 3.0 scores (p = 0.2 and 0.1, respectively). In the IDI analysis, the FIB-3 index showed significantly better discriminatory performance than the FIB-4 index (p = 0.02) but poorer discriminatory performance than the MELD 3.0 score and Child-Pugh classification (p = 0.004 and p < 0.001, respectively). CONCLUSIONS: The FIB-3 index showed better prognostic discrimination than the FIB-4 index and may serve as a simple age-independent fibrosis-related marker that complements established liver function-based prognostic models.