Baseline and Longitudinal Liver Stiffness Measurement Predict Outcomes in Primary Biliary Cholangitis: A Multicenter Study

BACKGROUND & AIMS: Liver stiffness measurement (LSM) using vibration-controlled transient elastography (VCTE) is a noninvasive tool for assessing severity in primary biliary cholangitis (PBC). While the baseline prognostic value of LSM has been recognized, the clinical significance of longitudinal LSM changes remains underexplored, especially in Asian populations. This study evaluated both baseline and dynamic LSM measurements for predicting adverse outcomes in PBC. METHODS: This multicenter retrospective cohort study analyzed 454 Japanese patients with PBC who underwent VCTE at seven tertiary centers. The primary outcome was a composite of liver-related events, liver transplantation, and all-cause mortality. Kaplan-Meier testing, Cox proportional hazards models, and receiver operating characteristic (ROC) curve analysis were adopted to assess the prognostic performance of baseline LSM and annual LSM changes (ΔLSM/year). RESULTS: During a median follow-up of 4.2 years, 14 patients (3.0%) either died or underwent liver transplantation, and 42 patients (9.3%) experienced liver-related events. Baseline LSM ≥ 8.0 kPa was independently associated with all-cause mortality (hazard ratio 4.79, 95% confidence interval 1.10-20.92). Patients with ΔLSM/year ≥ 2.1 kPa had significantly lower 5-year survival and event-free survival compared with those exhibiting slower disease progression. The area under the ROC curve values of baseline LSM for predicting liver-related events was high at 0.803. Furthermore, LSM ≥ 8.0 kPa stratifies prognosis even in patients who achieved normalization of alkaline phosphatase levels following treatment. CONCLUSIONS: Both baseline and longitudinal increases in LSM predict adverse outcomes in PBC and may signal the need for closer monitoring or early therapeutic intervention. TRAIL REGISTRATION: Approval number 5313.