FROM THE JOURNAL OF HEPATOLOGY
Uncapping the current Model for End-Stage Liver Disease score may provide a better path toward making sure that patients most in need of a liver transplant get one, results from a large, long-term analysis showed.
Established in 2002, the Model for End-Stage Liver Disease (MELD) scoring system “was arbitrarily capped at 40 based on the presumption that transplanting patients with MELD greater than 40 would be futile,” researchers led by Mitra K. Nadim, MD , reported in the September 2017 issue of the Journal of Hepatology (67[3]:517-25. doi: 10.1016/j.jhep.2017.04.022). “As a result, patients with MELD greater than 40 receive the same priority as patients with MELD of 40, differentiated only by their time on the wait list.”
Despite the cap at 40, they went on to note that the number of patients transplanted with a MELD score greater than 40 has increased by nearly threefold since 2002, with the greatest rates seen in Organ Procurement and Transplantation Network (OPTN) regions 5 and 7. Region 5 includes Arizona, California, Nevada, New Mexico, and Utah, while region 7 includes Illinois, Minnesota, North Dakota, South Dakota, and Wisconsin. To determine the effect of capping the MELD score, Dr. Nadim of the division of nephrology and hypertension at the University of Southern California, Los Angeles, and her associates used United Network for Organ Sharing (UNOS) data to identify 65,776 patients listed for a liver transplant from February 2002 to December 2012. They followed the patients for 30 days to analyze the wait-list mortality and post-transplant outcomes of adult patients with MELD scores greater than 40, compared with patients who had MELD scores equal to 40.
The mean age of patients was 53 years, and most were white men. The researchers reported that 3.3% of wait-listed patients had a MELD score of 40 or greater at registration, while 7.3% had MELD scores increase to 40 or greater after wait-list registration. In all, 30,369 patients (40.6%) underwent liver transplantation during the study period. Of these, 2,615 (8.6%) had a MELD score of 40 or greater at the time of their procedure. Compared with patients who had a MELD score of 40, those who had a MELD score of greater than 40 had an increased risk of death within 30 days, and the risk increased with rising scores. Specifically, the hazard ratio was 1.4 for those with a MELD score of 40-44, an HR of 2.6 for those with a MELD score of 45-49, and an HR of 5.0 for those with a MELD score of 50 or greater. There were no survival differences between the two groups at 1 and 3 years, but there was a survival benefit associated with liver transplantation as the MELD score increased above 40, the investigators reported.
“The arbitrary capping of the MELD at 40 has resulted in an unforeseen lack of objectivity for patients with MELD [score of greater than] 40 who are unjustifiably disadvantaged in a system designed to prioritize patients most in need,” they concluded. “Uncapping the MELD score is another necessary step in the evolution of liver allocation and patient prioritization.” They added that a significant number of patients with a MELD score of 40 or greater “likely suffer from acute-on-chronic liver failure (ACLF), a recently recognized syndrome characterized by acute liver decompensation, other organ system failures, and high short-term mortality in patients with end-stage liver disease. A capped MELD score fails to capture acute liver decompensation adequately, and data suggest that a model incorporating sudden increases in MELD predicts wait-list mortality better.”
Dr. Nadim and her associates acknowledged certain limitations of the study, including its retrospective design “and that factors relating to a patient’s suitability for transplantation or to a center’s decision to accept or reject a liver allograft, both of which affect graft and patient survival, were not accounted for in the analysis. Despite these limitations, the study results have important implications for improving the current liver allocation policy.”
The study was supported in part by the Health Resources and Services Administration. The researchers reported having no relevant financial disclosures.
PRIMARY SOURCE: J Hepatol. 2017;67[3]:517-25. doi: 1016/j.jhep.2017.04.022
