The researchers, led by Mark S Roberts, set out to describe disease-specific survival and the clinical variables that predict survival, using a large national cohort of adult liver transplant recipients.
They used the United Network for Organ Sharing to gather data on 17,044 adult patients who had received an initial orthotopic liver transplant between 1990 and 1996, with follow-up through to 1999.
From this information, disease-specific Kaplan-Meier survival plots and Cox Proportional Hazard models were estimated, and differences in the clinical characteristics of patients at the time of transplantation by disease were examined.
The study shows that overall post-transplant survival currently exceeds 85% in the first year, and is approaching 75% at 5 years.
Unadjusted Kaplan-Meier survival is improved for recipients who are younger, female, and in better clinical condition.
The study also shows that survival is a function of disease and level of illness. Cancer and fulminant liver failure have the poorest prognosis, along with alcoholic liver disease and the hepatitidies.
At the other end of the scale, transplant recipients with primary biliary cirrhosis and sclerosing cholangitis have the best prognosis for survival.
Furthermore, recipients who were outpatients before transplantation can expect to survive for longer than those transplanted from the hospital or intensive care unit.
Although the model for end-stage liver disease (MELD) score was designed to predict pre-transplant survival, patients with higher MELD scores have poorer post-transplant survival, but the MELD score is less predictive than the specific disease.
85% in the first year75% at five years
The researchers also found that differences in disease-specific survival are partially explained by differences in disease severity at the time of transplantation.
Concluding their report, the authors state that their findings show that disease-specific survival models indicate that there remains tremendous variability in survival as a function of underlying liver disease.
They add that a significant portion of the difference in survival between diseases arises from differences in clinical characteristics at the time of transplantation.