Transplantation of Kidneys from Black Cardiac-Death Donors Provide Black Recipients with the Best Long-Term Survival
Contrary to prevailing assumptions, Johns Hopkins researchers have shown that kidneys recovered from black donors who died from cardiac death offer the best survival rate for black recipients of a deceased-donor kidney.
This discovery, released online this week and appearing in the October 2008 issue of the Journal of the American Society of Nephrology, challenges the long-held belief that kidneys from white brain-death donors offers the best deceased-donor transplant survival rate for either black or white recipients.
“Our findings indicate that increased use of kidneys from cardiac-death donors could help reduce the organ shortage and improve outcomes for black kidney transplant recipients,” says lead author Jayme Locke, M.D., M.P.H., of the Department of Surgery at Johns Hopkins.
Locke and a team of Johns Hopkins researchers examined the outcomes of more than 25,000 black adults who received a deceased-donor kidney transplant between 1993 and 2006.
Results showed that black recipients who received a kidney from a black cardiac-death donor had a 70 percent reduction in the risk of kidney loss and a 59 percent reduction in risk for death when compared to black recipients who received a kidney from a white brain-death donor.
“Our data is consistent with the previous observation that black recipients seem to do better with kidneys from white brain-death donors than they do with kidneys from black brain-death donors or white cardiac-death donors, however, the fact that black recipients have the best outcomes with kidneys from black cardiac-death donors is significant,” says co-lead author Daniel Warren, Ph.D., of the Department of Surgery at Johns Hopkins.
He says that the exact mechanisms responsible for racial differences in outcomes after kidney transplantation are not known, however, the results suggest that the genetic background of the donor and recipient likely have a significant impact on long-term outcomes.
“We believe that an improved understanding of the molecular consequences of cardiac and brain death is critical to improving outcomes for all kidney transplant recipients and warrants further investigation,” he added.
There are currently more than 70,000 Americans waiting for kidney transplants. Only about 600 deceased-donor kidneys donated after cardiac death are currently used for transplantation versus 7,000 donated after brain death.
This discrepancy is due in part to the belief that kidneys that are exposed to cardiac death generally suffer more damage than kidneys that are exposed to brain death.
“Our results show this is not always true, and that is significant news for all patients waiting for a kidney,” says Locke.
Other researchers who worked on this study from Johns Hopkins include Robert Montgomery, M.D., Ph.D.; Andrew Cameron, M.D.; Joseph Melancon, M.D.; Dorry Segev, M.D.; Andrew Singer, M.D., Ph.D.; Christopher Simpkins, M.D., M.P.H.; Andrea Zachary, Ph.D.; Francesca Dominici, Ph.D.; Mary Leffell, Ph.D.; and Deborah McRann, B.S.N.