Race Not a Factor in Liver Transplant Survival

ROCHESTER, Minn., Nov. 2 -- Race did not determine 10-year survival of liver transplant patients treated at four academic centers, a finding contrary to a previous major national analysis that favored Caucasian survival.
Action Points
Explain to patients that this study found no link between race and outcome following liver transplantation, but other published studies have reported a link.
Discuss the possibility that, as the authors suggest, the findings of this study reflect a select population, such as patients treated at top centers, and may not be generalizable to national outcomes.
The 10-year survival probability was 54.4% for African-Americans (95% CI 41.1-72.1%) versus 50.7% for Caucasians (95% CI 46.5-55.3) and 55.7% for other races (95% CI 41.5 74.8), according to W. Ray Kim, M.D., of the Mayo Clinic, and colleagues. The study was published in the November issue of Hepatology.
The finding emerged from an analysis of data from 2,823 orthotopic liver transplant patients who were prospectively enrolled in two multicenter databases. The patients were treated from 1985 through 2000.
Although there was no association between race and survival during the entire study period, non-Caucasian race was associated with a worse survival among non-black minority patients who received transplants before 1994 (HR=1.60, P 0.01), the investigators wrote. But this association was attenuated when diagnoses (hepatitis B and hepatocellular carcinoma) were included in the model, (HR=1.39, P =0.04).
Athough the results directly contradicted a published report that used the United Network Organ Sharing (UNOS) database, Dr. Kim defended his findings. "An examination of our Kaplan-Meier curves and multivariable HRs indicated that the lack of a difference between Caucasian and African races that we observed was not a result of insufficient power," even though his sample size was much smaller --135 African-American patients versus 1,042 in the UNOS data.
Moreover, he said that a post hoc sample size calculation confirmed that "our sample size had enough power to detect a difference of 10% in survival, which was about the size of the difference in outcome in the UNOS report."
There was, however, a major difference between the two studies. Patients in the Kim study were from "select, high-volume academic centers, which would be expected to provide better outcomes than the national average."
In addition to the 135 African-American patients, the Kim study included data on 2,448 Caucasians and 240 minority non-black patients.
Dr. Kim and colleagues collected demographic data as well as liver disease diagnoses, and post-transplant follow-up on all patients.
They compared survival across races and found that survival was slightly higher for non-Caucasians at one year and 10 years, while Caucasians had a slight survival edge at five years -- but none of the differences was statistically significant.
Among the findings:
At one year, survival for African-Americans was 90.8% versus 86.5% for Caucasians, and 84.4% for other minorities.
The five-year survival probability was 69.2% for African-Americans (95% CI: 60.1-79.7) versus 72.2% (95% CI 70.1-74.4); and 67.5% for other races (95% CI60.5-75.3).
There was no difference in patient survival (P=0.162) or graft survival (P=0.582) among the racial groups.
Compared with recipients with viral hepatitis, patients with cholestatic disease or other liver disease categories had significantly better survival (P0.01).
"As proof of principle, our data, although put together from difference databases from different time periods, indicted that [orthotopic liver transplantation] recipients of a minority race, especially the African race, should not necessarily be expected to have poorer survival than Caucasians," Dr. Kim concluded.
Dr. Kim reported no potential conflicts of interest. The study was supported by grants from the National Institute of Diabetes and Digestive and Kidney Diseases. Additional source: HepatologySource reference: Lee, TH et al "Survival After Liver Transplantation: Is Racial Disparity Inevitable?" Hepatology 2007; 46:1491-1497