A new study on the determination of how livers are allocated for transplants examined the relationship between liver disease severity and quality of life, and found that the commonly used model for liver allocation is not a reliable indicator of general quality of life.
The results of this study appear in the February 2005 issue of Liver Transplantation, the official journal of the American Association for the Study of Liver Diseases (AASLD) and the International Liver Transplantation Society (ILTS). The journal is published on behalf of the societies by John Wiley & Sons, Inc. and is available online via Wiley InterScience.
Liver allocation is currently based on a patient's score on the Model for End-Stage Liver Disease (MELD), which uses results of three laboratory tests to predict short-term prognoses of liver disease. Because the MELD score is based on clinical findings, it is believed to be an accurate measure of liver disease severity. However, complications such as hepatic encephalopathy (which involves brain damage, personality changes, and intellectual impairment) and ascites (an accumulation of excess fluid in the abdomen), are not accounted for in the MELD score. MELD is now used in place of the Child-Turcotte-Pugh (CTP) model, which does take into account these complications and therefore is thought to be associated with quality of life.
Led by Sammy Saab, M.D., M.P.H., of the David Geffen School of Medicine at UCLA, the study included 150 adult patients awaiting their first liver transplant at the University of California Los Angeles between July 2003 and May 2004. Liver disease severity was assessed using both the CTP classification and the MELD score. In addition, patients completed two self-administered health-related quality of life questionnaires: the Medical Outcomes Short Form 36 (SF- 36) and the Chronic Liver Disease Questionnaire. The results showed that while quality of life is impaired in patients with end-stage liver disease, there is a poor correlation between quality of life scores and the severity of disease as measured by MELD.
"Patients consider quality of life in addition to survival when making healthcare decisions," note the authors. "In liver disease in particular, it is essential to understand the impact of their disease on their quality of life because of the prolonged wait for transplantation." They suggest that liver disease severity should not be assumed to be an accurate marker for quality of life and that future studies in patients awaiting liver transplants should include quality of life measures as well as survival.
An accompanying editorial by Richard B. Freeman, M.D. of the Division of Transplant Surgery at Tufts-New England Medical Center in Boston, MA, notes that while quality of life is an important component of healthcare decision-making, decisions about organ allocation must be considered within the context of the severe organ shortage. "In the current extremely constrained donor supply, the question is not whether an individual patient's HRQL [health-related quality of life] is poor enough to warrant intervention with transplantation but more directly, to whom, among all of the potential recipients of a given donor liver, should that donor liver be offered." He maintains that quality of life should not outweigh mortality risk in organ allocation decisions and that a patient must first be alive in order to measure his or her quality of life.
These articles are free and available at http://www.interscience.wiley.com/journal/livertransplantation.