Liver stiffness measurement by VCTE improves prediction of cholangitis outcomes
Liver stiffness measurement (LSM) by vibration-controlled transient elastography (VCTE) is independently associated with primary biliary cholangitis (PBC) outcomes, a study has shown.
“Its value as a surrogate endpoint for clinical benefit in PBC should be considered,” the authors said.
An international, multicentre, retrospective follow-up study was conducted in 3,985 patients with PBC seen at 23 centres in 12 countries. Those with at least one reliable LSM by VCTE and a follow-up ≥1 year were eligible for inclusion. An independent derivation (n=2,740) and a validation (n=568) cohort were then formed.
Time to poor clinical outcomes, defined as liver related complications, liver transplantation, or death, was the primary outcome. The investigators determined the hazard ratios (HRs) and 95 percent confidence intervals (CIs) using a time-dependent multivariable Cox regression analysis.
LSM was independently predictive of poor clinical outcomes in the derivation (5,324 LSMs, mean follow-up 5.0 years) and validation cohorts (1,470 LSMs, mean follow 5.0 years). The adjusted HRs per additional kPa were 1.040 (95 percent CI, 1.026‒1.054) and 1.042 (95 percent CI, 1.029‒1.056), respectively (p<0.0001 for both).
At baseline, the adjusted C-statistics were 0.83 (95 percent CI, 0.79‒0.87) in the derivation cohort and 0.92 (95 percent CI, 0.89‒0.95) in the validation cohort. The log-HR between 5 and 30 kPa increased as a monotonic function of LSM.
The predictive value of LSM remained stable over time. Of note, LSM improved the prognostic capacity of the biochemical response criteria, fibrosis scores, and prognostic scores. The 8 and 15 kPa cutoffs reliably differentiated low-, medium-, and high-risk groups. Of the patients, 40 percent were deemed medium to high risk according to LSM.