Prognostic factors for transplant-free survival in patients with secondary sclerosing cholangitis associated with critical illness

Objective: Secondary sclerosing cholangitis (SSC) represents a disease with a poor prognosis increasingly diagnosed in clinical settings. Notably, SSC in critically ill patients (SSC-CIP) is the most frequent cause. Variables associated with worse prognosis remain unclear. The primary aim of this study was to identify factors associated with transplant-free survival in SSC-CIP patients using readily available data.

Methods: A cohort of 47 patients diagnosed with SSC-CIP was retrospectively analysed for clinical, biochemical and endoscopic variables. Kaplan-Meier survival curves, log-rank tests and univariate Cox proportional hazards models were used to assess associations with transplant-free survival. A multivariable Cox regression model was constructed using Lasso regularisation and validated with Bootstrap resampling. Model performance was assessed using the C-statistic for discrimination.

Results: Kaplan-Meier analysis identified bile duct obstruction requiring stent placement, and cholangitis episodes, as significant prognostic factors. In univariable analysis, age over 47 years (HR 2.61 (95% CI 1.02, 7.06), p=0.04), at least one cholangitis episode (HR 2.46 (95% CI 1.005, 6.06), p=0.04), stent placement (HR 2.89 (95% CI 1.13, 7.38), p=0.03), lower albumin levels (HR 0.52 (95% CI 0.28, 0.97), p=0.04) and higher international normalised ratio (INR) (HR 3.22 (95% CI 1.09, 9.53), p=0.03) were significant. Multivariable analysis showed that age at diagnosis, albumin and INR were significant independent predictors. The C-index was 0.78 (95% CI 0.65, 0.91), surpassing the model of end-stage liver disease score's prognostic accuracy (Concordance Index at 3 years: 66.2% vs 74.9%).

Conclusion: These findings provide valuable insights for establishing standard exception criteria for this rare liver disease, which could lead to improved organ allocation. Further prospective multicentre studies are necessary to validate our findings.