Stratification of Perioperative Mortality and Long-Term Survival in Liver Transplant Recipients at Listing: Validity of The Liver Transplant Risk Score (LTRS) in a European Cohort

Abstract

Introduction: The liver transplant risk score (LTRS) was developed to objectively stratify the risk of postoperative mortality in patients undergoing liver transplantation at the time of their evaluations. The primary aim of this study was to validate the LTRS in adult patients transplanted in Europe. Methods: The LTRS was estimated for all recipients of deceased donor liver transplants in Europe between 2002 and 2013 using the European Liver Transplant Registry. MELD score, body mass index, age, and presence of renal failure were used to calculate the LTRS at the time of listing. Postoperative mortality rates at the 30-day, 90-day, 1-year, and 5-year time points were compared amongst groups stratified by the LTRS. Results: The study population was represented by 12,063 patients. The range of the LTRS spanned from 0 (best prognosis) to >5 points (worst prognosis). Overall postoperative mortality at 90-days was 6.8%, and 10.7% at 1-year. For patients with an LTRS=0, 90-day mortality was 5.1% versus 12.9% for patients with LTRS >5 (P<0.001). At 1-year, the mortality rate was 8.4% for patients with an LTRS=0 versus 38.7% for patients with LTRS>5 (P<0.001). The C-statistics for 90-day and 1-year mortality were 0.64 (95% CI 0.62-0.66; P<0.001) and 0.65 (95% CI 0.64-0.67; P<0.001) respectively. Conclusion: Postoperative mortality of European liver transplant recipients can be estimated using the LTRS. Our findings validate the utility of the LTRS as a tool that could reduce variability in the identification of patients at increased risk of poor outcomes after liver transplantation.