There are significantly more patients needing a transplanted kidney than there are willing donors. A study published last month in the Journal of the American Medical Association estimated that there were 90,000 candidates for transplantation as of the beginning of 2012. Yet the number of deceased donor transplantations has hovered around 11,000 in recent years.
That gap is being filled increasingly by matching up living donors—who often have a family member who needs a kidney—with recipients who can physiologically accept the donated kidney. Family and friends of a transplant candidate often can't donate directly to the candidate because the kidney is incompatible. But if donors and recipients are pooled, matches or chains can be created that increase the total number of possible transplants.
The number of paired kidney donations has risen in each of the past nine years and has grown from essentially nothing in the past 12. There were 521 paired kidney donations in 2012, up from 442 in 2011 and only two in 2000, according to data from the Organ Procurement and Transplantation Network.
But Segev and two co-authors argued in a recent report in the American Journal of Transplantation that too few transplant centers are actively participating in formal kidney exchanges. The researchers found that 161, or 77%, of 207 U.S. transplant centers did at least one kidney exchange in the three years through 2011. Yet, they found that a small number of the centers were doing a large amount of the total number of kidney exchanges. Half of all paired kidney donations were being performed by only 22 transplant centers, according to the study.
Transplant centers face logistical and financial hassles that may be slowing their participation in kidney pairing and chains, but those obstacles should not be insurmountable, Segev said. Insurance coverage can be difficult to manage. With a paired donation, the recipient's insurer pays for the donor's costs, but if that donor lives in another state, that creates network payment issues, he said.
And, driven by revenue concerns, some transplant center executives may want to match only patients within their own program to maximize the number of transplants it performs. That approach is misguided because it means fewer patients will get the transplants, and fewer transplants means higher costs, said Dr. John Milner, a transplant surgeon at the Loyola University Medical Center, Maywood, Ill., and a member of the medical board of the not-for-profit National Kidney Registry, the largest paired kidney transplant program.
Milner, who participated in a chain of 30 kidney transplants last year involving 17 hospitals, said a transplant center receives roughly $100,000 to perform a kidney transplant, but as they do more transplants the marginal cost drops. Once a center has covered its sizable fixed costs, more of that revenue is profit, which creates an incentive to keep transplants in-house, Milner said.
But the patient and society would gain from getting more transplants done and by doing them sooner. The cost of the transplant is recovered in about two years, primarily through reduced dialysis costs, said Alvin Roth, the Craig and Susan McCaw professor of economics at Stanford University and a winner of the 2012 Nobel Memorial Prize in Economic Sciences for research that contributed to kidney exchange programs. The more centers and patients participating, the better off everyone would be, Roth said. “This is one of the cases where the best treatment is also the cheapest,” he said.
Segev said there is some talk about the federal government creating a single reimbursement approach for paired kidney donation, which could encourage participation by clearing some of the insurance-related obstacles.
Others would like to see a single, national paired kidney program created. Ruthanne Leishman, kidney paired donation program manager for a pilot program at the OPTN, said she thinks that having a single program running the matching would maximize the number of successful matches and transplants. But she noted that others feel that innovation would be stifled by not having competing programs.
It's unclear how many additional transplants could take place if more centers participated in kidney pair programs. Segev's study suggested that there could be 1,000 more transplants a year, but Milner estimated it to be more like 2,000 or 3,000 a year.
Regardless of the exact number that would benefit, more patients in the pool of potential matches would produce greater results, Milner said. “We need everyone to know and participate.”