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An analysis of data two years since implementation of the kidney allocation system (KAS) shows a number of longer-term patterns, with success in a number of key system goals.

Trends include the following:

• Deceased donor kidney transplants have increased 9.1 percent since KAS implementation; deceased donation also has continued to increase substantially from 2014 through 2016. This rise is not necessarily attributable to KAS.
• There was no substantial change in transplant volume in any region post-KAS Year 2 versus post-KAS Year 1.
• From Year 1 to Year 2 after KAS implementation, the percentage of kidney recipients age 18 to 49 decreased slightly and transplants for recipients age 50 and older increased slightly.
• Kidney transplant percentages by recipient ethnicity are now more similar to the ethnic makeup of waiting list candidates. This is a noticeable difference from pre-KAS kidney allocation, and it is one of the expected outcomes of KAS.
• Longevity matching (matching kidneys most likely to function the longest with recipients likely to need them the longest) continues to perform as intended. More than half of adult recipients with an Estimated Post-Transplant Survival (EPTS) score between zero and 20 percent (indicating the longest potential need) received kidneys with a Kidney Donor Profile Index (KDPI) score between zero and 20 percent (indicating the longest potential function).
• Significant “bolus effects” occurred for candidates who received additional transplant priority under KAS, including those with very high immune sensitivity and those with lengthy dialysis times prior to transplant listing. Many of these candidates received a transplant soon after the new policy was implemented because of the increased priority they received. Transplants have declined as fewer candidates remain on the waiting list, but the percentage of transplants going to these groups is still higher than the rate prior to KAS.
• The percentage of transplant recipients experiencing delayed graft function (DGF) increased initially post-KAS but has since declined slightly, though still remains higher than pre-KAS. This finding may be influenced by the bolus effect for recipients who have been on dialysis longer-term.
• The kidney discard rate after KAS has also remained higher than the period before KAS implementation – 19.9 percent in Year 2 post-KAS. Discard rates are largely linked to KDPI scores; less than three percent of kidneys with a KDPI of zero to 20 are discarded, compared to 60 percent of kidneys with a KDPI between 86 and 100 percent.
• Rates of patient survival under KAS have decreased slightly but remain very high. The overall rate of kidney graft survival (organ function post-transplant) also has shown some decrease. The difference in graft survival rates is affected to some degree by factors such as recipient age and the amount of time the kidney is preserved between recovery and transplantation. Since recipient immune sensitivity and dialysis duration also relate to outcomes, and since more highly sensitized candidates and longer-term dialysis candidates received transplants soon after KAS implementation, the “bolus effects” described earlier may also affect post-transplant patient and graft survival rates.

The OPTN/UNOS Kidney Transplantation Committee will continue to analyze these trends carefully, as well as other data that will be available longer-term.

These recent findings are based on limited data. They must be interpreted cautiously and further tracked to assess whether observed trends will be sustained.

Richmond, Va. – The OPTN/UNOS Board of Directors, at its meeting June 5 and 6, approved a national system to assign liver allocation priority for candidates with exceptional medical conditions.

“While there have been review boards in each region to consider individual exception scores for liver candidates for a number of years, this has sometimes led to differences in how much priority candidates may get from one area to another,” said Stuart Sweet, M.D., Ph.D., OPTN/UNOS Board President. “The new system will create more consistency and will also scale its criteria to balance the priority between exception candidates and those with standard scores. This is a crucial step forward in addressing geographic disparities in liver transplant access. ”

The majority of liver transplant candidates receive an allocation score based on either the Model for End-Stage Liver Disease (MELD) or the Pediatric End-Stage Liver Disease (PELD) model. These scores estimate candidates’ short-term risk of death without receiving a liver transplant. While MELD and PELD provide reliable estimates for most liver candidates, others have diseases or unusual complications that the formulas do not capture as well. These candidates receive an “exception score” comparable to the degree of illness of MELD and PELD candidates.

The newly approved National Liver Review Board (NLRB) will replace the individual review boards in each of the 11 OPTN regions. Reviewers will be drawn from a nationwide pool of liver transplant physicians and surgeons, who will review exception requests on an anonymous basis for candidates not listed at the transplant program of any of the reviewers. The policy also establishes standard allocation point thresholds for a number of common medical conditions needing an exception score, as well as guidance documents for NLRB members to consult when considering a non-standard exception.

While no Board action was planned or taken to address liver distribution, the OPTN/UNOS Liver and Intestinal Organ Transplantation Committee briefed the board on its development of a new policy proposal intended to reduce geographic disparity in liver candidates’ medical urgency scores at transplant. The committee is not currently considering an 8-district concept circulated for public comment in 2016.

In other action, the Board approved a guidance document to help transplant professionals discuss with transplant candidates the option of potentially receiving a transplant from a donor at potentially increased risk for disease transmission based on Public Health Service criteria.

United Network for Organ Sharing (UNOS) serves as the Organ Procurement and Transplantation Network (OPTN) by contract with the U.S. Department of Health and Human Services, Health Resources and Services Administration, Division of Transplantation. The OPTN brings together medical professionals, transplant recipients and donor families to develop national organ transplantation policy.

UNOS has been named a Top Workplace program in the Richmond, Va. region. The announcement was made March 6 in the Richmond Times-Dispatch.

For the fourth consecutive year, UNOS is recognized as one of the top 10 among mid-sized companies (125 to 399 employees) based on employees’ responses to an annual survey.

The top winners in each of the four categories based on company size will be announced at the Top Workplace 2017 program May 4 at the University of Richmond and in a special section of The Times-Dispatch to be published May 5.

The program is conducted by the Richmond Times-Dispatch and Workplace Dynamics, LLC.