The effect of changes of model for end-stage liver disease score during waiting time on post-liver transplant mortality

Abstract

Model for End-Stage Liver Disease (MELD) score is found to be a robust predictor of mortality while on waiting list for liver transplantation. However, studies have shown inconsistent results for transplant MELD as a predictor of posttransplant mortality. To find whether utilization of MELD at listing, at transplant, or Δ MELD while waiting can predict outcome at a national transplant center, which is not part of an organ sharing network. Retrospective analysis of patients listed for liver transplantation at the New Zealand Liver Transplant Unit (NZLTU) with calculation of MELD score at the time of listing and at transplant with/without adjustment points for hepatocellular carcinoma (HCC). Between 1998 and 2005, 264 adult patients were listed for liver transplantation. Median age at transplant was 49years (range 16-70) and 65% were male. The most common etiology was viral hepatitis (50%). A total of 48 patients (20%) had known HCC. MELD scores (adjusted and nonadjusted) at listing and at transplantation were similar across all primary liver diseases (P=0.88, 0.93, respectively). Adjusted MELD scores were significantly higher in patients listed for HCC compared to those without HCC (P<0.001; hazard ratio 1.33; 95% confidence interval=1.21-1.46). MELD scores at transplant did not correlate with either 3 or 12months mortality (P=0.336, 0.228, respectively). This finding was consistent whether the change of MELD during waiting time was >1 point or less (P=0.67). Waiting time does not appear to influence posttransplant survival (P=0.75). In a country with a single transplant center and organ retrieval organization, the addition of MELD score to current minimal listing criteria does not improve prioritization of patients on the waiting list or predict posttransplant survival. Also, adjusting MELD score for HCC would unfairly disadvantage patients listed without HCC.