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 and appearing in the
October issue of the Journal of the
American Society of Nephrology, challenges the
long-held belief that kidneys from white brain-death
donors offer 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," said lead
author Jayme Locke, of the Department
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,"
said co-lead author Daniel Warren, also of the
Department of Surgery.
Warren 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
"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 said.
There are currently more than 70,000 Americans waiting
for kidney transplants. Only about
600 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
exposed to brain death.
"Our results show this is not always true, and that is
significant news for all patients waiting for
a kidney," Locke said.
Other Johns Hopkins researchers who worked on this
study are Robert Montgomery, Andrew
Cameron, Joseph Melancon, Dorry Segev, Andrew Singer,
Christopher Simpkins, Andrea Zachary,
Francesca Dominici, Mary Leffell and Deborah McRann.