Inequities of the Model for End-Stage Liver Disease: an examination of current components and future additions.

PURPOSE OF REVIEW: The aim of this article is to examine the limitations of the Model for End-Stage Liver Disease (MELD) components and summarize data on promising new predictor variables. RECENT
FINDINGS: Promising modifications to MELD have been aimed at identifying more accurate measurements of the current MELD components and at improving survival prediction in earlier stages of cirrhosis. Incorporation of new measurements of cholestasis, coagulopathy and renal dysfunction should improve accuracy and reliability of MELD in predicting mortality in end stage liver disease. Direct bilirubin may be a more specific surrogate marker of liver disease than total bilirubin and further investigation of its use in liver mortality risk models in warranted. The recently developed liver-specific international normalized ratio may mitigate thromboplastin-related variation in international normalized ratio measurements. The incorporation of more accurate assessments of renal function into MELD should improve prognostic accuracy and would avert systematic biases associated with serum creatinine. Hepatic venous pressure gradient and serum sodium are promising predictors of liver-related mortality that may warrant further consideration.
SUMMARY: Modification to MELD, particularly if intended for use in liver transplant allocation, should be based upon objective, reliable, reproducible and readily available predictors; and be able to withstand rigorous model development and validation.