Excess mortality on the liver transplant waiting list: Unintended policy consequences and model for End‐Stage Liver Disease (MELD) inflation

Abstract

The Model for End-Stage Liver Disease (MELD) allocation system for liver transplantation provides "exceptions" for diseases such as hepatocellular carcinoma (HCC). It was the aim of this study to assess equipoise between exception candidates and nonexception candidates on the waiting list and to assess if the exception system contributes to steadily increasing regional MELD at transplant. In all, 78,595 adult liver transplant candidates between January 2005 and December 2012 were analyzed. Yearly trends in waiting list characteristics and transplantation rates were analyzed for statistical association with MELD exceptions. Regional variations in these associations and the effect of exceptions on regional MELD scores at transplant were also analyzed. 27.29% of the waiting list was occupied by candidates with exceptions. Candidates with exceptions fared much better on the waiting list compared to those without exceptions in mean days waiting (HCC 237 versus non-HCC 426), transplantation rates (HCC 79.05% versus non-HCC 40.60%), and waiting list death rates (HCC 4.49% versus non-HCC 24.63%). Strong regional variation in exception use occurred but exceptions were highly correlated with waiting list death rates, transplantation rates, and MELD score at removal in all regions. In a multivariate model predicting MELD score at transplant within regions, the percentage of HCC MELD exceptions was the strongest independent predictor of regional MELD score at transplant. Conclusion: Liver transplant candidates with MELD exceptions have superior outcomes compared to nonexception candidates and the current MELD exception system is largely responsible for steadily increasing MELD scores at transplant independent of geography. (HEPATOLOGY 2015;61:285-291) See Editorial on Page 28 T he advent of the Model for End-Stage Liver Disease (MELD) allocation system 1 for deceased donor liver transplant recipients in February 2002 profoundly changed the organ allocation system in the U.S. It was understood at the time, however, that MELD would not reflect mortality risk in certain diseases. These diseases were generally not associated with progressively worsened liver function but had a high risk of death or eventual mortality without transplant. Of these "exceptional" diseases, the most prevalent was hepatocellular carcinoma (HCC).Built into the MELD allocation system was an "exception" to the MELD score for HCC and this exception was designed to give extra MELD points to those transplant candidates with early HCC in order to allow them to compete fairly for deceased donor liver grafts despite having relatively preserved liver function in many cases. Fundamentally, the exception system was designed to allow equal access to liver transplantation between candidates with progressive liver dysfunction and those with morbid conditions who's risk of death was not reflected by the calculated MELD score. After 3 years of adjustments in the number of MELD points assigned to candidates with Abbreviations: HCC, hepatocellular carcinoma; MELD, M...

Intravenous immunoglobulins in liver transplant patients: Perspectives of clinical immune modulation

“…Direct clinical implications of the organ shortage, like pre-LT rising transfusion need, prolonged waiting times and increasing MELD scores, have shown to promote the risk of immunologic imbalance [127,134,148] . This could be one explanation for the reported outcome deterioration in the MELD era [5,[10][11][12][13][14] . As a consequence, pre-LT immunologic screening has been recently recommended, particularly in high-risk liver patients [137,138,149] .…”

“…As a result, donors' and recipients' selection criteria were considerably expanded and numbers of LTs performed were significantly increasing in recent years. Due to a dramatic donor organ shortage, growing waiting lists, prolonged waiting times and increasing pre-LT mortality rates have been reported [4][5][6] . To respond to this challenging situation, the model of end-stage liver disease (MELD) score was implemented to give priority to the most urgent patients on the waiting lists.…”

Model for end‐stage liver disease‐based allocation system: On the right path, but not there yet

“…3 Interestingly, the American situation regarding patients enlisted to transplant with exceptions to the MELD-based system is quite similar to the Brazilian one, which can be exemplified by the percentage of enlisted patients with HCC, 19.00% in the American study 1 and 19.60% in the post-MELD era of the Brazilian study.…”

“…This letter regards the interesting article published by Northup et al 1 The researchers demonstrated that, under the Model for End-Stage Liver Disease (MELD)-based allocation system for liver transplantation, patients with exceptions to this system, especially those with hepatocellular carcinoma (HCC), have a great advantage over nonexception candidates in waiting list mortality and in access to transplant, leading to inequity.…”

“…Differently from Northup et al, 1 we used an intention-totransplant approach, evaluating survival of patients enlisted to transplantation, regardless of being transplanted. 3 We estimated long-term survival of transplant candidates using the parametric models that best fitted their Kaplan-Meier's survival curve (Gompertz's model for pre-MELD era and normal-log model for post-MELD era), demonstrating that patients enlisted to transplant during the pre-MELD era had an estimated 5-year survival of 43.17% and a 10-year survival of 41.75% independently of being transplanted, whereas those enlisted during the post-MELD era had estimated survivals of 53.54% and 44.64%, respectively.…”