Changes to Kidney Allocation Anticipated
by William Bry, M.D., surgical director, Kidney Transplant Program, California Pacific Medical Center
To address inadequacies in how kidneys from deceased donors are currently allocated, the United Network for Organ Sharing (UNOS) is working with transplant professionals and patients nationwide to implement a better system. These FAQs provide more details about the forthcoming changes.
Q. Why is a new kidney allocation system being created?
A. Transplant professionals and patients have long advocated for a national change in how kidneys from deceased donors are allocated. Currently healthier kidneys are being given to recipients with shorter expected survivals and vice versa. Also, not enough medical criteria are being used to judge which kidneys are best for which patients, thereby limiting the overall success rate of kidney transplantation. Dissatisfaction is so great with the existing national system that two-thirds of the country—including Northern California—uses local allocation criteria instead of the national rules.
Q. What will the new system look like?
A. Donor kidneys will be ranked in quality by 13 different criteria that affect how long the kidney should last once transplanted. These criteria will comprise a donor profile index (DPI)—a score between 0 to 100. Zero indicates a kidney that has the longest expected survival (from a young, healthy donor), while 100 indicates poorer survival (from an older donor with many of the 13 negative attributes). A patient and his/her doctor can specify what kidney index scores he/she is willing to accept. The better the DPI specified, the longer the wait.
Once the new system takes effect, individuals on the kidney transplant waiting list will be ranked by their expected survival after transplantation. This equation will be based on factors including age, number of years on dialysis, diabetes and weight, among others. The amount of time spent on the waiting list will also play a role in one’s ranking. With the new system, one’s wait time will start either when he/she starts dialysis or his/her kidney function drops below 20%.
Q. Who will be offered any particular kidney?
A. Kidney transplant outcomes show that the success of a transplant is closely tied to a similarity in age between donor and recipient. Therefore, the current proposal is to offer kidneys from donors within fifteen years of the potential candidate’s age. So a 45-year old dialysis patient would receive a kidney from a donor between the ages of 30 and 60, while a 55-year old patient would have a deceased donor between the ages of 40 and 70. An additional policy which should further improve outcomes states that the best 20% of donor kidneys will be preserved for the 20% of wait listed patients with the longest expected post-transplant survivals.
Q. How will the new system change who gets transplanted?
A. It is predicted that fewer elderly patients (> 64 years) and fewer diabetic patients will receive transplants.
Q. What is the next step?
A. This proposal will go to the UNOS Board of Directors. If approved, the policy will have two rounds of public comment. Modifications to the policy may result from the outcomes of these reviews. Patients are encouraged to participate in the public comment phase. All told, the process may take 18 to 24 months.
Q. How will I know my status on the wait list?
A. When the new system is launched, a calculator tool will enable individuals to estimate their wait time for a kidney and their estimated lifespan either with a transplant or with dialysis only. When the patient enters his/her age and medical information, he/she will receive a graph comparing outcomes with a variety of options.
article from April 2010 Kidney Review newsletter