Background/aims: Recently, the Korean Association for the Study of the Liver (KASL) introduced a noninvasive test-based approach that uses the fibrosis-4 (FIB-4) index followed by vibration-controlled transient elastography (VCTE) to identify high-risk patients with metabolic-associated steatotic liver disease (MASLD). In this study, the KASL two-step approach was validated by assessing the risk of liver-related event (LRE) development.
Methods: We retrospectively analyzed 8,131 patients with MASLD who underwent VCTE between 2012 and 2020. The index date was defined as the date of the VCTE measurement. Using the KASL two-step approach (FIB-4 index and subsequent VCTE), patients were stratified into four groups (low-, intermediate-low-, intermediate-high-, and high-risk groups). Outcomes, including LREs such as decompensation (DCC) or hepatocellular carcinoma (HCC) were evaluated.
Results: During the follow-up (median 46.6 months), 86 (1.1%) patients developed LREs (39 [0.5%] with DCC and 47 [0.6%] with HCC). The KASL two-step approach classified 67.6%, 17.7%, 5.7% and 9.0% of patients in the low-, intermediate-low-, intermediate-high-, and high-risk groups, respectively. The cumulative incidences of LREs increased proportionally according to risk stratification (0.07%, 0.10%, 0.29%, and 1.51% at 3 years and 0.35%, 0.26%, 1.94% and 5.46% at 5 years). The overall accuracy in predicting LREs ranged from 67.7-99.8%. The FIB-4 index and subsequent Agile3+, Agile 4, or FibroScan aspartate aminotransferase scores showed similar predictive abilities compared to the KASL approach.
Conclusion: The KASL two-step approach is an effective and practical method for risk stratification in patients with MASLD, optimizing patient care through early identification of high-risk individuals.