Model for End-stage Liver Disease: Did the New Liver Allocation Policy Affect Waiting List Mortality?—Invited Critique

Austin et al present an analysis that evaluated the impact of the MELD-based allocation policy on access to liver transplantation and posttransplantation outcomes. They used a statistical method based on a large national database that accounts for seasonal trends. Their primary end point was to establish whether the DHHS directive of decreasing waiting list mortality was achieved as a result of MELD implementation. The authors used the 1999-2004 Organ Procurement and Transplantation Network files, which permitted collection of more than 2 years of time points before and after the February 27, 2002, MELD intervention. Their model revealed a steady postintervention decline in waiting list mortality by 0.09 death per 1000 registrants per month after an initial increase of 2.2 deaths per 1000 registrants per month after MELD implementation. Between March 1999 and February 2002, a 3% decline in the death rate occurred, corresponding to an identical 0.09 death per 1000 registrants per month before MELD implementation. The 2005 Organ Procurement and Transplantation Network STAR annual report reveals that the death rate has been declining since 1995 and in fact remained relatively flat after 2002. This steady decline in death rate despite an increase in the number of patients on the waiting list can be attributed to a 34% increase in the number of transplantations performed since 1999, independent of any impact MELD implementation had. Another point made by the authors is that MELD implementation had no impact on survival after transplantation. Although the registry data support this finding, patient diagnoses at transplantation were altered after implementation. The authors make reference to the increase in the number of patients with hepatocellular carcinoma who undergo transplantation, who typically have lower calculated MELD scores and hence better outcomes. The percentage of patients with hepatocellular carcinoma who undergo transplantation increased from 5.8% in 1999 to 14.1% in 2004.¹ Significant geographic variation is evident, and in some centers, this variation has increased to more than 50%.² The impact MELD has on survival remains a controversial subject, and the better outcomes in patients with hepatocellular carcinoma may be balanced by reported negative correlations with higher MELD scores, especially in patients with hepatitis C virus.³