MELD score versus conventional UNOS status in predicting short-term mortality after liver transplantation

The Model for End-stage Liver Disease (MELD) provides a score able to predict short-term mortality in patients awaiting liver transplantation (LT). In the early 2002, United Network for Organ Sharing (UNOS) has proposed to replace the conventional statuses 3, 2B, and 2A with a modified MELD score. However, the accuracy of the MELD model to predict post-transplantation outcome is fairly elusive. In the present study we investigated the predictive value of the MELD score for short-term patient and graft mortality in comparison with conventional UNOS status. Sixty-nine patients listed at UNOS status 3 (n = 5), 2B (n = 55) or 2A (n = 9) who underwent LT were enrolled according to strict criteria. No donor-related parameters affected 3-month patient survival. Through univariate Cox regression, pretransplantation international normalized ratio (P = 0.049) and activated partial thromboplastin time (P = 0.032) were significantly associated with 3-month patient survival, although not in the subsequent multivariate analysis. The overall MELD score was 17 +/- 6.63 (median: 16, range: 4-34), increasing from UNOS Status 3 to 2A (r(2) = 0.171, P = 0.0001). No significant difference occurred in the median MELD score between patients who underwent a second LT and those who did not (P =0.458). The inter-rate agreement between UNOS status and MELD score after categorization for clinical urgency showed a fair agreement (kappa = 0.244). The 3-month patient and graft mortality was 15.94% and 20.29% respectively. The concordance statistic did not find significance between UNOS status and MELD score for 3-month patient (P = 0.283) or graft mortality (P = 0.957), although the MELD score revealed a major sensitivity for short-term patient mortality (0.637; 95%CI: 0.513-0.75). These findings suggest the need to implement MELD model accuracy for both inter-rate agreement with UNOS Status and patient outcome.