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MELD Exceptions and Rates of Waiting List Outcomes

A B Massie1, B Caffo, S E Gentry

  • 1Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA.

American Journal of Transplantation : Official Journal of the American Society of Transplantation and the American Society of Transplant Surgeons
|September 17, 2011
PubMed

Insights

Model for End-stage Liver Disease (MELD) exceptions for liver transplants are increasing and benefit patients. However, varying exception rates across organ procurement organizations (OPOs) may indicate geographic inequity in liver allocation.

Area of Science:

  • Transplantation science
  • Health services research
  • Organ allocation policy

Background:

  • The Model for End-stage Liver Disease (MELD) score is used for deceased donor liver allocation.
  • Exceptions to MELD-based allocation exist for patients with scores not reflecting true mortality risk.
  • Variations in exception practices among organ procurement organizations (OPOs) and over time are not well understood.

Purpose of the Study:

  • To investigate differences in MELD exception practices among OPOs.
  • To determine if the use of MELD exceptions has increased over time.
  • To assess whether patients receiving MELD exceptions have better outcomes compared to non-exception patients.

Main Methods:

  • Analysis of longitudinal data for 88,981 adult liver candidates from the United Network for Organ Sharing (2002-2010).
  • Examined proportions of Hepatocellular Carcinoma (HCC) and other MELD exceptions at OPO and regional levels.
  • Used multinomial logistic regression to compare waitlist mortality and transplant odds for exception vs. non-exception patients.

Main Results:

  • Significant variation in HCC and other exception rates existed across OPOs and regions.
  • The proportion of patients receiving HCC and other exceptions increased significantly from 2002 to 2008.
  • MELD exceptions (HCC and other) were associated with decreased waitlist mortality risk and increased odds of transplant.

Conclusions:

  • MELD exception policies provide advantages to patients, potentially improving transplant access and survival.
  • Geographic disparities in MELD exception rates among OPOs may indicate or create inequities in liver allocation.
  • Further research is needed to address the observed geographic variations in exception practices.

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