No Difference In Survival Rate For Children Of Different Races Undergoing Liver Transplantation
Two studies presented at the annual meeting of the American Association for the Study of Liver Diseases paint a different picture of survival based on racial group for adult and child recipients of liver transplants.
Researchers at the Baylor College of Medicine used a United Network for Organ Sharing dataset of 2700 pediatric liver transplant recipients age 17 years and under to determine if there were any differences in survival between racial groups -- Caucasians, Hispanics, African-Americans, and Asians. They looked at graft and patient survival for the period between 2002 and 2007, and found that, although there were differences in leading cause for inclusion on the transplant list, age at time of transplant, and sex of transplant recipients, there was no difference in either allograft or patient survival rate between the racial groups. Similarly, they found no difference in PELD/MELD score (a standard scoring system for disease severity) at time of transplant and percentage of patients undergoing multiorgan transplants.
"The finding that children in the current era have no disparities in outcomes was quite surprising, since our study is a small part of a larger research project that examined both adult and pediatric transplantation outcomes and found African-Americans faring significantly worse at three years following transplantation," said the study's presenter Natasha Becker, MD.
A study conducted by researchers at the Mayo Clinic also found differences in long-term survival rate among racial groups for adult transplant recipients. This study examined race of the transplant recipients, transplant centers, and payer status. All 11565 single-organ liver transplant recipients from 2003 to 2005 were included in one of four groups -- African-American, Caucasian, Asian/Pacific Islander, or other.
Researchers found no difference in short-term survival in patient and graft, but they did find significant differences after two years. The center in which the transplant was performed accounted for some of the discrepancy, but after controlling for that, African-Americans were found to have a lower patient and graft survival rate compared to the other three groups. The authors found no explanation for this based on transplant center, payer, or disease severity pretransplantation.
The Mayo Clinic researchers were also surprised by the results. "Since our previous study has demonstrated that race had no effect on posttransplantation survival in select, academic centers in the US," said Young-Suk Lim, MD, PhD, "we had hypothesized that the different outcome after liver transplantation between races in US would disappear after stratification by centers. But, lower long-term posttransplantation outcome of African-American remained after multivariable adjustment for center, payer, or pretransplantation disease severity."
"Perhaps elucidating the differences between the pediatric and adult populations will allow us to understand the disparities that are seen in the adult population," said Dr. Becker. Dr. Lim is also looking to future studies to explain the racial disparity, "We are in the process of investigating the issue of center-specific effect a bit deeper. If the center is not the reason, further investigation into potential genetic differences may be warranted."