Changes in Liver Stiffness, Measured by Magnetic Resonance Elastography, Associated With Hepatic Decompensation in Patients With Primary Sclerosing Cholangitis.

Background & Aims: Single measurements of liver stiffness (LS) by magnetic resonance elastography (MRE) have been associated with outcomes of patients with primary sclerosing cholangitis (PSC), but the significance of changes in LS over time are unclear. We investigated associations between changes in LS measurement and progression of PSC.

Methods: We performed a retrospective review of 204 patients with patients who underwent 2 MREs at a single center between January 1, 2007 and December 31, 2018. We collected laboratory data and information on revised Mayo PSC risk and model for end-stage liver disease scores, the PSC risk estimate tool, and levels of aspartate transferase at the time of each MRE. The ΔLS/time was determined by the change in LS between the second MRE compared to the first MRE divided by the time between examinations. The primary endpoint was development of hepatic decompensation (ascites, variceal hemorrhage or hepatic encephalopathy).

Results: The median LS measurement was 2.72 kPa (interquartile range, 2.32-3.44 kPa) and the overall change in LS was 0.05 kPa/y. However, ΔLS/y was 10-fold higher in patients anticipated to have cirrhosis (0.31 kPa/y) compared to patients with no fibrosis (0.03 kPa/y). The median LS increased over time in patients who ultimately developed hepatic decompensation (0.60 kPa/y; interquartile range, 0.21-1.26 kPa/y) vs but remained static in patients who did not (reduction of 0.04/y; interquartile range, reductions of 0.26 to 0.17 kPa/y) (P < .001). The ΔLS/y value associated with the highest risk of hepatic decompensation was Δ0.34 kPa/y (hazard ratio [HR], 13.29; 95% CI, 0.23-33.78). After we adjusted for baseline LS and other risk factors, including serum level of alkaline phosphatase and the Mayo PSC risk score, ΔLS/y continued to be associated with hepatic decompensation. The optimal single LS cut-off associated with the hepatic decompensation was 4.32 kPa (HR, 60.41; 95% CI, 17.85-204.47). A combination of both cut-off values was associated with risk of hepatic decompensation (concordance score, 0.93; 95% CI, 0.88-0.98) CONCLUSIONS: A single LS measurement and changes in LS over time are independently associated with hepatic decompensation in patients with PSC. However, changes in LS occur slowly in patients without advanced fibrosis or hepatic decompensation.