Liver Stiffness, Patient-Reported Fatigue, and Pruritus in Primary Biliary Cholangitis and Primary Sclerosing Cholangitis: A Cross-Sectional Study

Background: Fatigue and pruritus are common and disabling in primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC), but their severity is not reliably explained by standard biochemical markers. Whether liver stiffness measured by transient elastography reflects these symptoms remains unclear. This study examined associations between liver stiffness and fatigue and pruritus in PBC and PSC, and between routine biochemical measures and symptom burden. Methods: This cross-sectional analysis included 107 patients (56 PBC, 51 PSC) from a prospective autoimmune liver disease registry. Fatigue was assessed with the CLDQ-29 fatigue domain and pruritus with the CLDQ-29 pruritus item or the itch visual analog scale. Multivariable linear and ordered logistic regression examined associations between liver stiffness and fatigue and pruritus, adjusted for disease type, age, and sex. Spearman correlations assessed associations between liver stiffness and clinical and laboratory variables, with Benjamini–Hochberg correction. Receiver operating characteristic analysis assessed discrimination. Results: Patients with PBC were older (59 vs. 51 years; p < 0.001) and more often female (96.4% vs. 56.9%; p < 0.001) than those with PSC. Liver stiffness (6.0 vs. 6.8 kPa; p = 0.101), fatigue scores, pruritus scores, and itch VAS were similar between groups. Liver stiffness was not associated with fatigue (β = 0.005; p = 0.835) or pruritus (OR = 0.97; p = 0.190) after adjustment; only age was associated with fatigue (β = 0.021; p = 0.020). Among laboratory measures, only ALP remained correlated with liver stiffness after correction (ρ = 0.309; adjusted p = 0.027). In PSC alone, higher liver stiffness was associated with worse pruritus (ρ = −0.37; p = 0.009), a finding not seen in PBC. Liver stiffness alone showed limited discrimination for fatigue (AUC 0.46) and pruritus (AUC 0.56); a model with disease type, age, and sex improved discrimination modestly for fatigue (AUC 0.60) but not for pruritus (AUC 0.57). Conclusions: Liver stiffness was not associated with fatigue or pruritus in the overall cohort of patients with PBC and PSC, and a possible association with pruritus in PSC needs confirmation. Patient-reported outcomes should be assessed alongside biochemical and elastographic measures, and how they relate to objective measures of disease remains an open question.