Prognostic Significance of Bile Duct Loss in Early-Stage Primary Biliary Cholangitis: A Long-Term Observational Study.

Background & aims: Primary biliary cholangitis (PBC) is a chronic, slowly progressive, and autoimmune liver disease. This study aimed to establish the clinicopathological features that accurately predict long-term prognosis in patients with early-stage PBC.

Methods: The present long-term (8.8 years), multicenter, and retrospective investigation enrolled 274 treatment-naïve PBC patients who had undergone liver biopsy. Among them, 207 patients with albumin-bilirubin (ALBI) grade 1 were categorized as clinical early-stage, and 230 patients with Nakanuma stage 1/2 were classified as pathological early-stage. The prognostic factors related to the time to liver-related events (LRE) were statistically evaluated.

Results: Cox regression analysis identified Nakanuma bile duct loss score of ≥ 1 as a significant independent factor associated with LRE development in clinical early-stage PBC patients (hazard ratio [HR] 12.89, 95% confidence interval [95% CI] 1.60-103.96, P = 0.016). Kaplan-Meier testing revealed that the cumulative incidence of LRE was significantly higher in patients with bile duct loss score of ≥ 1 than in those with bile duct loss score 0 (log-rank test; P < 0.001). Similarly, bile duct loss score could predict LRE in pathological early-stage PBC patients, as confirmed by both multivariable Cox regression (HR 6.60, 95% CI 1.37-31.86, P = 0.019) and Kaplan-Meier (log-rank test; P < 0.001) analyses.

Conclusions: Nakanuma bile duct loss score may be a valuable prognostic indicator in the early clinical and pathological stages of PBC.