Although age isn’t considered when matching kidney donors with their recipients, it should be

Nov 1 2004

Although age isn’t considered when matching kidney donors with their recipients, it should be, according to a new study being presented at the American Society of Nephrology’s 37th Annual Meeting and Scientific Exposition in St. Louis, Missouri.

The research demonstrates the impact of matching donors and recipients by age that would take increased advantage of the potential lifetime of a transplanted kidney. It found that matching young kidneys to young recipients could potentially extend the life of a young patient by close to two and a half years.

This is the first time a study has compared the ages of donor kidneys with their recipients to determine how to maximize the use of a donated kidney. The age of the donated kidney greatly affects how long the transplanted organ will survive. An average younger donor kidney transplant lasts over ten years in younger recipients.

“It is surprising that the age of the kidney donor and its recipient has never been taken into consideration in the matching process, given that donated kidneys are a scarce, life-saving resource,” says Herwig-Ulf Meier-Kriesche, Department of Medicine, University of Florida, Gainesville, Florida. “Doing this would help extend lives and reduce the number of patients on the transplant waiting list, which is growing exponentially in size.”

Matching the age of kidney donors to recipients is contrary to the current donor matching system in the United States that gives optimal young kidneys to recipients who die long before the kidney would stop functioning. At the same time, young patients are given old kidneys, which deteriorate long before the patient dies, requiring them to return to dialysis or be re-transplanted, which further increases the number of patients on the burgeoning waiting list.

The research examined over 74,000 deceased donor kidney transplants between 1990-2002. The age of the donors and their recipients were compared to determine how to best use the survival time of a transplanted kidney according to age.

Findings showed that 6,850 graft years could have been saved over this twelve year period if young donor kidneys (ages 15-50) were matched with young recipients under the age of 60 and older kidneys (age 50+) were given to older patients over the age of 60. For the 9,250 transplants that would have been affected by this reallocation, this would have saved 6,850 graft years over this twelve-year period, which would have increased the life of each transplant patient by an average of nine months. When projected over the lifetime of a transplanted kidney, the kidney could survive three more years, amounting to 27,750 more graft years.

This new allocation model shows that if all young kidneys now going to old recipients in the United States would go to young patients, in exchange for the same number of old kidneys going to older recipients, then it would potentially extend the life of the younger population by close to two and a half years.

The study results will be presented at a news briefing from 12:15 – 1:15 p.m. on Saturday, October 30 in Room 276 of the America’s Center. The study abstract, “Shifting the Transplant Kidney Allocation by Recipients Life Expectancy Can Significantly Increase The Populations Cumulative Graft Survival” (SU-FC104) will be presented during a Free Communications session on Sunday, October 31 at 4:10 p.m. in Room 276 of the America’s Center.

The ASN is a not-for-profit organization of 9,000 physicians and scientists dedicated to the study of nephrology and committed to providing a forum for the promulgation of information regarding the latest research and clinical findings on kidney diseases. ASN’s Renal Week 2004, the largest nephrology meeting of its kind, will provide a forum for more than 12,000 nephrologists to discuss the latest findings in renal research and engage in educational sessions relating advances in the care of patients with kidney and related disorders from October 27- November 1, 2004 at the America’s Center in St. Louis, Missouri.

http://www.asn-online.org/