Aspartate aminotransferase‐to‐platelet ratio index outperforms Fibrosis‐4 in 2843 Korean patients with metabolic dysfunction‐associated steatotic liver disease

Abstract Aim The definition of metabolic dysfunction‐associated steatotic liver disease (MASLD) has recently been proposed. We aim to investigate the diagnostic efficacy of noninvasive fibrosis markers in predicting liver fibrosis in patients with nonalcoholic fatty liver disease (NAFLD), metabolic dysfunction‐associated fatty liver disease (MAFLD), and MASLD. Methods This retrospective study involved 2843 patients diagnosed with steatotic liver disease at six tertiary hospitals in South Korea. Liver fibrosis was assessed using vibration‐controlled transient elastography, and various noninvasive markers, including the aspartate aminotransferase‐to‐platelet ratio index (APRI), Fibrosis‐4 index (FIB‐4), NAFLD fibrosis score (NFS), and serum Mac‐2‐binding protein glycosylation isomer were analyzed. Results Among 1106 patients, 79.9% met criteria for NAFLD, MAFLD, and MASLD. The APRI had area under the receiver operating characteristic curve (AUC) values of 0.819, 0.821, and 0.818 for liver fibrosis ≥F2, and 0.819, 0.824, and 0.884 for liver fibrosis ≥F3, and 0.890, 0.884, and 0.889 for fibrosis ≥F4 in NAFLD, MAFLD, and MASLD, respectively. The FIB‐4 index showed AUC values of 0.776, 0.793, and 0.778 for fibrosis ≥F2, 0.788, 0.814, and 0.79 for fibrosis ≥F3, and 0.846, 0.859, and 0.856 for fibrosis ≥F4. The APRI consistently had the highest AUC values, except in individuals older than 64 years for fibrosis ≥F4. Conclusions The APRI was the most effective noninvasive fibrosis marker across NAFLD, MAFLD, and MASLD, particularly in age‐stratified analyses. Further research is needed to establish standardized cut‐off values and enhance the clinical utility of these markers in managing liver fibrosis.