Race influences liver transplant survival in US

NEW YORK, Jan 25 (Reuters Health) - Black and Asian Americans have a poorer prognosis after liver transplant compared with white and Hispanic patients, according to findings from a US study.

Researchers report that certain health factors, such as the underlying reason for the transplant, may partly explain the racial differences. However, there is a "clear need" to fully investigate the reasons, they conclude in the January 26th issue of The Lancet.

The study, based on national data for the years 1988 to 1996, showed that African Americans and Asian Americans were less likely to be alive 2 and 5 years after liver transplantation compared with whites and Hispanics.

In addition, blacks were nearly twice as likely to reject their new organs than patients of other races were. Twelve percent of African Americans had chronic organ rejection, compared with 6% to 7% among the other races.

Dr. Paul J. Thuluvath of Johns Hopkins University in Baltimore, Maryland, led the study.

According to his team, higher rates of chronic organ rejection among African Americans have been blamed on poorer compliance with medication and inadequate insurance coverage. But, Thuluvath and colleagues write, "there is no convincing evidence to support these suggestions."

Instead, the researchers speculate, some yet unidentified immune system factors might be at work. And, they add, most available immune-suppressing anti-rejection drugs were tested largely among whites. "There might be a need to test these drugs more rigorously in minorities," they write.

As for Asian Americans, those who had the liver infection hepatitis B had a lower survival rate compared with hepatitis B-infected patients of other races. The infection was the most common cause of chronic liver disease among Asian-American transplant patients.

Overall, 2-year survival rates were 74% and 69% among black and Asian patients, respectively. For whites and Hispanics, the rates were 83% and 79%, according to the report. Even when other factors were considered, African Americans were more than one-third more likely to die within 2 years, and Asian American were one-quarter more likely.

Five-year survival rates for the two races were also considerably lower. And according to Thuluvath's team, organ rejection and other factors such as the severity of patients' illness prior to transplant--which was generally greater among African Americans--cannot explain the lower 5-year survival.

"Our study suggests that there is a clear need for prospective studies to examine our observations further," the investigators write.

Until then, the researchers add, any reasons for the racial differences seen in this study "will remain speculative."

"Moreover," they conclude, "the higher rate of chronic rejection in African Americans suggests that there should be more rigorous drug trials in this patient population."

SOURCE: The Lancet 2002;359:287-293.