Differences in access to liver transplantation: Disease severity, waiting time, and transplantation center volume

Background: The Model for End-Stage Liver Disease (MELD) score has been used since February 2002 to allocate livers for transplantation from deceased donors according to medical need. Allocation based on MELD scores should ensure that sicker patients receive transplants first regardless of transplantation center volume. Objective: To determine whether the MELD score at transplantation and waiting time of liver transplant recipients differs by transplantation center volume. Design: Analysis of the Organ Procurement and Transplantation Network database. Centers were classified according to the volume of transplantations performed in 2005: high ( >= 100 transplantations), medium (50 to 99 transplantations), and low (<50 transplantations). Setting: Transplantation centers in the United States. Patients: 20 075 transplant recipients between 27 February 2002 and 30 April 2006. Measurements: MELD scores and waiting times of liver transplant recipients. Results: Transplant recipients at high-volume centers had lower MELD scores (35.1% with MELD scores <= 18 vs. 22.7% and 27.0% at medium- and low-volume centers, respectively; P< 0.001), and the median MELD score was 22 compared with 24 at both medium- and low-volume centers. Despite having lower MELD scores, recipients at high-volume centers also experienced shorter waiting times (median waiting time, 69 days vs. 98 days and 94 days at medium-and low-volume centers, respectively; P < 0.001). Limitations: The definition of transplantation center volume was subjective. The recent implementation of MELD precluded analysis of differences in long-term outcomes related to waiting time or center volume. Conclusions: The MELD scores and waiting time of liver transplant recipients differed by transplantation center volume. High-volume centers have shorter waiting times and perform more transplantations for less sick patients. The reasons for these differences are unclear but warrant further investigation.