Utility of MELD and Child-Turcotte-Pugh scores and the Canadian waitlisting algorithm in predicting short-term survival after liver transplant.

Background: The Model for End-Stage Liver Disease (MELD) and Child-Turcotte-Pugh (CTP) scores are important predictors for survival after liver transplantation (LT). The objective of this study was to compare the utility of MELD and CTP scores with Canadian waitlisting algorithm in transplantation (CanWAIT) status for predicting 90-day survival after LT.

Methods: Retrospectively, we analyzed all 228 liver transplants performed in adults by the Atlantic Liver Transplant Program since 1985. These cases included combined transplants, retransplants and those after fulminant liver failure. MELD and CTP scores were calculated, and CanWAIT status and waiting time on the day of LT determined. We used c-statistic for 90-day outcome as the endpoint (survival), comparing areas under the receiver operating characteristic (ROC) curves for MELD and CTP scores and CanWAIT status.

Results: Mean (and standard deviation [SD]) MELD score was 18 (SD 12); CTP score, 10 (SD 3); and waiting time, 97 (SD 132) days. At the time of LT, 54% were in CanWAIT status 1; 4% in 1T; 14% in 2; 11% in 3; 6% in 3F; 4% in 4; and 7% in status 4F. Overall 90-day survival was 80% (95% confidence interval [CI] 75%-85%), exceeding the predicted survival by MELD scale with transplant of only 51% (CI 47%-55%). By c-statistic, CanWAIT is a clinically relevant predictor of 90-day outcomes in LT. By multivariate regression analysis, only CanWAIT status and age were found to have independent associations for short-term outcomes after LT.

Interpretation: CanWAIT status stratifies LT patients better and predicts short-term outcome more accurately than MELD or CTP scores, and so should not be replaced by MELD or CTP scores. This observation should be confirmed by a prospective and multicentre study in Canada.