Category Archives: Kidney Exchange Media Reprints

Undercover Economist: Stakes in kidneys


By Tim Harford, July 13, 2007 8:56 am

Economics is all about realising gains from trade, but sometimes our qualms get in the way. For example, most of us have a spare kidney that – since kidneys tend to fail in pairs – is not terribly useful to us. A few – over 6,300 on the UK waiting list – could have their lives transformed if they could get hold of a compatible kidney. The few have so much to gain; the rest of us, not that much to lose. Donating a kidney is not risk-free: it kills three out of 10,000 donors, which is three times the death rate from pregnancy. The logic of economics is that there is a cash price at which both donor and recipient would walk away smiling.

Of course, it isn’t legal to complete this transaction – unless you happen to live in Iran, where recipients are allowed to provide cash compensation to donors. From a utilitarian cost-benefit viewpoint, the prohibition doesn’t make much sense. But then, neither did the outrage over the Dutch Big Donor Show, in which three desperately ill patients competed for the kidney of a terminally ill donor. In the end, of course, the show turned out to be a hoax; the patients were in on the stunt and the donor was an actress. At the awful news that none of these sick people would receive a cure, the world breathed a puzzling sigh of relief.

Since kidney trades are illegal, it’s hardly surprising that there is a severe shortage of kidneys. Four hundred Britons die each year while on the waiting list for an organ transplant. The shortage is getting worse as diabetes and hypertension damage more kidneys.

All is not lost. While most people feel queasy at the idea of exchanging a kidney for, say, £20,000, they are happy with the idea of exchanging a kidney for another kidney.

In such a kidney exchange, two pairs of friends agree a swap in search of more compatible kidneys: I donate a kidney to your friend if you donate a kidney to my friend.

Most people seem to think this is morally acceptable. Quite what the difference is between being paid in cash and being paid in kidney is a question I will leave to the philosophers. (It has only recently become legal in the US and the UK. It was not until March this year that the US Department of Justice clarified its opinion that while cash was “valuable consideration” and thus contravened the law, a kidney was not.)

However, those who have a pragmatic bent have turned their attention to making these kidney exchanges work better. The economists Al Roth, Tayfun Sonmez and Utku Unver have been working with transplant surgeons in New England to design a kidney exchange programme. Twenty-two transplants have taken place so far. The UK has a legislative framework in place to support something similar, and the first paired transplant is likely to take place over the next few months.

It is technically demanding to set up a kidney exchange, but getting it right should pay off. Think about an altruistic or “undirected” donor who offers to donate a kidney wherever it might be useful. Before the kidney exchange, that person’s kidney would help only one person. The carefully designed market now allows such a donation to set off a small avalanche of swaps.

Roth has turned his attention to three-way or even four-way swaps. His calculations have demonstrated that the four-way swap is unnecessary: three-way swaps solve almost all compatibility problems. Since a four-way swap means eight simultaneous operations, that is a relief.

Keynes once expressed a wish that economists could be as useful as dentists. Professor Roth and his colleagues have gone one better.

Tim Harford’s book, ‘The Undercover Economist’, is now out in paperback

Paired donations give organ transplants a brighter future (PPG), May 8, 2007

photo posted on

Rebecca Droke, Post-Gazette
After having renal failure caused by diabetes, Robb Wilson (here with his wife, Lora, at their Churchill home), received a kidney and pancreas transplant in 1999 from a donor who had died. His wife couldn’t donate one of her kidneys to her husband, but she later gave one in an altruistic donation to a stranger.

By Mark Roth Pittsburgh Post-Gazette

When Lora Wilson of Churchill decided to donate one of her kidneys last year to anyone who needed it, she got an unexpected reaction.

While most people supported her decision to become a living kidney donor, some were completely thrown by her wish to become an “altruistic” donor, giving her precious organ to someone she didn’t know.

“When I started telling people,” Ms. Wilson said, “some of them really couldn’t get the altruistic part. Sometimes I would tell somebody, and they would actually burst into gushing tears!”

As it turned out, the patient who got Lora Wilson’s kidney didn’t stay a stranger for long. Dolores Iannacone met Ms. Wilson after the surgery, when they were still in the hospital at UPMC Montefiore, and they now talk every week.

Ms. Wilson, executive director of Pittsburgh Bone & Joint Surgeons in McKeesport, made her momentous decision largely because her husband, Robb, had received a kidney and pancreas transplant eight years ago that saved his life.

She represents a group of people who may help create the next big breakthrough in organ transplant surgery.

Listen in
Lora Wilson explains how she began thinking of becoming an altruistic donor after her mother died in August, 2005.
Lora Wilson gives some of her thoughts on the value of being an altruistic donor.
Robb Wilson tells a story of a woman who can’t bring herself to meet the recipients of her dead daughter’s organs, but is saving messages from them to give to her daughter’s children.

It’s known as paired kidney donation, an attempt to ride the crest of a growing wave of living kidney donors.

Most living kidney donors give their organs to people they know. But a large number who volunteer to donate can’t do so because their blood types or other biological factors make them a poor match with the person they know.

Paired kidney donation gets around that problem by swapping organs to create better matches. In the simplest form, one patient’s mismatched donor would give his kidney to another patient, and that recipient’s donor would give his organ to the first patient.

The doctors and other scientists who are promoting this kind of kidney swapping say it can work better if there are sometimes three or four pairs of people involved, and can be enhanced even further if an altruistic donor like Ms. Wilson can trigger a chain of organ exchanges.

In fact, going up to four-way exchanges can accommodate nearly every match possible in a large database of people, said Utku Unver, a University of Pittsburgh economist who helped pioneer computerized kidney matching with colleagues Alvin Roth of Harvard University and Tayfun Sonmez of Boston College.

Fewer than 200 paired kidney donations have taken place to date, but the networks being set up to promote such exchanges are growing rapidly, and some experts predict they could account for as many as 2,000 kidney transplants a year in the future.

Living kidney donors now comprise nearly 40 percent of the 17,000 transplants done each year in the United States. It’s the one area where there has been some success in erasing the chronic gap between people waiting to get organs and those willing to donate them.

While only a handful of living kidney donors have given their organs to people they didn’t know, as Lora Wilson did, they can have a disproportionate impact in creating optimal matches in a kidney exchange network.

That showed up in one recent computer matching run performed by the Alliance for Paired Donation, based in Toledo, Ohio.

Using software invented by Carnegie Mellon University computer scientists, the Alliance discovered that if it did not include any altruistic donors, it could find only one two-way exchange among its 100 patient-donor pairs, said Dr. Michael Rees, Alliance medical director.

But when it included the few altruistic donors, it was able to create one potential four-transplant chain, three three-transplant chains and four two-transplant chains, Dr. Rees said.

In a four-way chain, the altruistic donor’s kidney would go to pair A, whose kidney would go to pair B, whose kidney would go to Pair C, and that final pair’s kidney would then become available for another altruistic donation.

Ms. Wilson said her doctors suggested at one point that her kidney might be able to trigger such an exchange, but final blood tests ruled that out.

While doctors can match kidney patients and donors ahead of time based on their blood types and certain white blood cell markers, they still have to do a last-minute blood mixing test to see if the two people have strong antibody reactions to each other.

These 11th-hour “crossmatch” failures are another reason why kidney exchanges would work best with a larger database.

Although the chief motivation of kidney exchange programs is to increase the number of successful transplants, they also play off the hope that someone will be more willing to donate a kidney if his loved one will get one in return.

To make sure no one changes his mind at the last minute, the transplant surgeons doing exchanges plan them to start at the same time.

“These surgeons are literally on the cell phone with each other sometimes, saying ‘OK, I’m going to start now,’ ” said Dr. Tuomas Sandholm, one of the Carnegie Mellon scientists who developed new computer matching software.

The other big advantage: Living kidney donations last much longer than those that come from people who have died. The average cadaver kidney lasts about 11 years, while the average living kidney lasts 20 years.

The Alliance for Paired Donation is one of four voluntary kidney exchange networks in America.

The largest one, the Paired Donation Network, is also based in Ohio, and its new president, Dr. Ronald Shapiro, is director of pediatric kidney transplantation at Children’s Hospital here.

Pittsburgh’s CORE, the Center for Organ Recovery and Education, which coordinates organ transplants in this region, just started listing patient-donor pairs in October on the Paired Donation Network’s database, but has not arranged any local kidney exchanges yet.

Two slightly older networks are the New England Program for Kidney Exchange, based in Boston, and a program run by Dr. Robert Montgomery at Johns Hopkins University in Baltimore.

Outside the country, there is a paired donation network in the Netherlands and a highly successful one in South Korea, which is known for its high rate of altruistic donors.

Most other organ donations are governed by a national organization known as UNOS, or the United Network for Organ Sharing. Toledo’s Dr. Rees would like to see UNOS set up a national database for kidney exchanges as well, but not yet.

“I don’t think UNOS is in a position to run it now,” he said, partly because its staff lacks the expertise, and partly because the existing networks can try out different strategies to find the best way of matching donors and recipients.

One reason UNOS has been slow to move into the kidney exchange arena is that until recently, it was unclear whether these swaps were legal.

To prohibit buying and selling organs, U.S. law says no “valuable consideration” can be given in exchange for an organ. The question in this case was whether giving one kidney for another violated that rule.

About a month ago, though, the Department of Justice ruled that kidney exchanges are legal, opening the way for a national network.

Dr. Steve Woodle, chief of transplant surgery at the University of Cincinnati and a founder of the Paired Donation Network, estimated that there may already be 3,500 to 8,000 Americans who have volunteered to donate a kidney to a friend or relative but are not compatible, and who could become part of a national database.

“The computer matching techniques are an important part of paired donation,” Dr. Woodle said, “but the most important part right now is getting the patients identified and educating the transplant groups” about how important kidney exchanges can be.

One vital part of the educational campaign may be letting potential donors know that today, the surgery to obtain a kidney is not only extremely safe, but can often be done laparascopically, by inserting tubes through tiny incisions.

That hastens recovery time and reduces pain, Pittsburgh’s Dr. Shapiro said, and may require a donor to be off work for only two to three weeks.

“It’s still major surgery, of course,” he said. “I tell patients that the first day after surgery they feel like a truck hit them; the second day like an SUV hit them; and the third day like a VW Beetle hit them; and then the fourth day they can go home.”

Tony Tye, Post-Gazette
Abeid “Bey” Johnson, 35, of Knoxville, is hoping to join Pittsburgh’s kidney exchange network, but first, he needs to find a donor who could give a kidney to someone else so that Mr. Johnson can get one in return. His mother and brother volunteered, but she was the wrong blood type and his brother turned out to have high blood pressure. Now, he is waiting to see if an aunt or a friend passes the screening tests to become a donor. Through performances by his singing group, Artistree, and other outreach efforts, Mr. Johnson has raised about $17,000 toward a kidney transplant. In the meantime, he goes to dialysis three days a week at Fresenius Medical Care in Mount Oliver.

Easing the Kidney Shortage: Wall St. Journal

In the Wall Street Journal on June 17, 2004 in an article title “Easing the Kidney Shortage” in his column CAPITAL, David Wessel writes:

Renal Donors Swap Recipients If Blood Types Don’t Match; Cheating on Priority Lists

June 17, 2004; Page B1

As of noon yesterday, 58,470 people in the U.S. were waiting for a kidney transplant. Most won’t get one this year. There aren’t enough donated kidneys to go around. Surgeons transplanted just 15,129 kidneys last year. Now a band of transplant surgeons and economists are trying to fix that by creating a moneyless market for exchanging kidneys. Most transplanted kidneys come from a person who has died, a supply that grows slowly because of ignorance about the need for donations or grieving relatives’ reluctance. But a kidney taken from a live donor works better, and almost everyone has a spare. As techniques improve for removing healthy kidneys and for suppressing the body’s tendency to reject a transplant, doctors increasingly turn to kidneys from living donors, usually relatives. Last year, 43% of kidneys transplanted in the U.S. came from living donors, up from 28% a decade ago. But a biological barrier often blocks a transplant from a relative. In about a third of all would-be pairs, blood types are incompatible. In others, the sick person has antibodies that can initiate a rejection of the donated organ. It’s heartbreaking “to have the treasure of the live donor and then have that not go forward because of a biological obstacle,” says Massachusetts General Hospital transplant surgeon Francis DelMonico.

Occasionally, transplant centers spot a way out: One New England father with blood type A couldn’t donate a kidney to his daughter with blood type B. So he gave a kidney to a teenager with blood type A, and the teenager’s sister gave a kidney for the man’s daughter. New England’s transplant centers have done six such exchanges. Baltimore’s Johns Hopkins University has done seven.

In the past year, Hopkins also has done two exchanges that involved three transplants each, an undertaking that requires six operating rooms and 60 medical professionals (see diagram2). In New England, Washington, D.C., and elsewhere, would-be donors unable to give a kidney to a loved one instead have given a kidney to a stranger. The loved one, in turn, is rewarded by being moved up on the waiting list for a dead person’s kidney.

Such swaps occur, though, only when the right combination appears or a flurry of e-mails among transplant centers produces the right mix. A highly organized system alerts transplant centers when a dead person’s kidney is available; there isn’t any system for a man who can’t give to, say, his wife, but wants to advertise his willingness to make a swap. Hopkins transplant surgeon Robert Montgomery figures that 2,000 or more people could get transplants each year if there were a national database of such donors.

Transplants are expensive: Johns Hopkins says the cost is roughly $120,000 when everything is included. Medicare usually foots the bill for patients without private insurance, though it doesn’t pay that much. Buying or selling a kidney in the U.S. is illegal.

Donors, recipients and relatives involved in three-way kidney transplant at Johns Hopkins Hospital in Baltimore last year

Lawyers and ethicists, after substantial deliberation, decided a few years ago that kidney swaps like those done in Boston and Baltimore are acceptable. And doctors agree on some simple rules: The donor must travel to the hospital where the recipient is; participants may keep identities private if they choose; all operations in a swap begin simultaneously to avoid anyone backing out halfway through the swap.

While the doctors were working all this out, Harvard economist Alvin Roth, a specialist in designing moneyless markets like the one that matches medical residents to teaching hospitals, was pondering the problem. He proposed to a visiting protégé, Utku Ünver of Istanbul’s Koc University, that the two teach a course using kidneys as an example. Thinking about kidney donors and recipients, it turned out, was similar to thinking about the way colleges allocate dorm rooms, a problem Mr. Ünver and colleagues had studied.

The result was an article published in the Quarterly Journal of Economics last month by the two men and a colleague from Koc, Tayfun Sönmez, that describes how to structure a kidney exchange to identify potential swaps among a large pool of people with rules that make it very hard for anyone to cheat.

Cheating is an issue in transplants. In Chicago, for instance, cardiac doctors have been accused by local prosecutors of overstating the severity of patients’ illnesses to move them up on the priority list for hearts. And rules, such as those that depend on how long one has been waiting for an organ, don’t always anticipate human cleverness; rules had to be changed, for instance, when doctors began to put babies on waiting lists for heart transplants before they were born.

The economists’ premise is simple: Don’t expect anyone to do anything that isn’t in his or her self-interest. As long as a computer can identify the one kidney in the pool that best suits a patient, the system is foolproof, the economists say.

Massachusetts General’s Dr. DelMonico admits to some skepticism when the economists approached him last fall. But the collaboration has blossomed over the past few months. Dr. DelMonico handles the intricacies of forging a consensus among the 14 transplant centers in New England and finding money to support a computerized system to implement the economists’ design.

Harvard tissue-typing specialist Susan Saidman, meanwhile, is working to perfect a computer system to simplify the process of checking to be sure potential recipients don’t have antibodies that could cause them to reject an otherwise suitable donor’s kidney.

The most compelling moment so far came when Dr. Saidman gave the economists details on 45 pairs in which the would-be donor was unable to give a kidney to the intended recipient. Even though each of the 45 had a donor willing to spare a kidney, all were stuck waiting for the right person to die. With swaps involving two kidneys, the economists found, eight transplants were possible. If swaps involving three kidneys were possible, then 11 transplants were possible.

The Boston Globe Cross-donor system planned for region’s kidney patients (BG) June 5, 2004

The Boston Globe

Cross-donor system planned for region’s kidney patients

By Scott Allen, Globe Staff, June 5, 2004

New England transplant surgeons, working with a Harvard economist, are planning a unique organ-trading system that could ease the shortage of kidneys available for transplant by giving willing donors a strong new incentive to give their kidneys to strangers.

Currently, hundreds or even thousands of potential organ recipients must join a long transplant waiting list even though friends or family members are willing to donate a kidney, because the would-be donors prove to be a poor match with the patient. The new system would take these willing donors and connect them with similarly mismatched donors elsewhere in New England, allowing them to cross-donate kidneys to each other’s friends or loved ones.

Since 2001, New England doctors have performed six of these paired exchanges, including one last year when two women each successfully donated a kidney to the other’s husband at Massachusetts General Hospital. But the idea’s effectiveness is limited by the difficulty of finding well-matched patients and donors.

To overcome this, Harvard economist Alvin Roth developed a new computerized donor tracking system that could allow doctors to arrange scores of exchanges per year in New England alone, over time significantly reducing a regional kidney waiting list that now stands at 2,237. In a limited test of his system, Roth found eight matches from 45 potential donors who had previously been rejected. Applied nationally, Roth believes the system could potentially save thousands of lives.

”This could be quite a substantial increase in the number of live donors,” said Dr. Francis L. Delmonico, medical director of the New England Organ Bank in Boston, which manages the region’s organ supply.

The paired-exchange system appears to be surmounting the ethical concerns that have sunk other ideas for fostering more organ donation. Congress long ago barred financial incentives to encourage donors, but medical ethicists are also concerned about any system that pressures people to undergo a risky operation that does not benefit their own health. Though most organ donors recover fully, an estimated one in 3,000 die and all of them lose their backup kidney in the event they develop kidney disease themselves.

Writing in The New England Journal of Medicine recently, Delmonico argued that organ exchanges can be ”models of altruism” as long as everyone knows the risks and no money is involved. A transplant surgeon at Mass. General, he has proposed Roth’s matching system to the panel of surgeons that sets kidney transplant policy in New England.

”I don’t think that there are any ethical issues” to expanding the number of trades, said Dr. Paul Morrissey of Rhode Island Hospital, chairman of the Renal Transplant Oversight Committee. ”It’s just setting up the mechanism to carry it out.”

Even tough critics such as Dr. Lainie Friedman Ross, medical ethicist at the University of Chicago, agree that the paired-exchange system can be fair. Ross has faulted other approaches for discriminating against one group of patients in favor of another, but she said she’s ”totally in favor” of Roth’s system.

The paired-exchange system comes 50 years after Dr. Joseph Murray carried out the nation’s first kidney transplant at what is now Brigham and Women’s Hospital, using a kidney taken from the patient’s identical twin to avoid organ rejection. Today, in part to antirejection drugs, surgeons can often transplant kidneys between perfect strangers even if the donor’s tissue is a poor match.

As a result, almost a quarter of live donors are not related to the patient who gets their kidney.

Roth estimates that nearly half of willing donors do not donate because their blood type doesn’t match the patient or the patient’s immune system would attack the donated organ, and because there is currently no system for keeping track of rejected donors.

Roth’s system would change that by entering potential donors’ names into a computer database and searching for a match. Long interested in improving the transplant system, Roth has written a detailed paper with two other economists outlining how the system will work.

With the kidney transplant waiting list now up to 61,000 across the country, transplant surgeons and patient groups will be watching the New England experiment closely. Morrissey said the system is sure to save lives, but ”whether it adds 15 transplants a year or 150 remains to be seen.”

In recent years, surgeons have become increasingly desperate for transplant organs, with some even suggesting that people get paid to fill out an organ donor card.

So far, the handful of paired exchanges completed in New England have created happy endings for people who were increasingly hopeless.

For instance, Susanna Polletta of Watertown, Conn., had wanted to donate a kidney to her husband, Rosario, whose kidneys were gradually failing as a result of a long battle with lupus.

But both her blood and tissue types were a complete mismatch for him, so Rosario remained on a transplant waiting list for years, relying on home dialysis to keep his body going.

By chance, Rosario’s doctor at Mass. General, Nina Rubin, was treating another man who had the same problem: Tracy Scott of Chichester, N.H., was languishing on the transplant waiting list even though his wife, Robin, was ready and willing to donate a kidney. Then Rubin discovered that Robin’s kidney was a match for Rosario while Susanna’s matched Tracy’s. ”It was like a miracle,” said Rosario Polletta.

On Feb. 25, 2003, the women donated their kidneys to the two men, and, 15 months later, all four have resumed their normal lives.

”I probably have more energy now than I did when I was 30,” said Polletta, now 47.

Scott Allen can be reached at 

© Copyright 2004 The New York Times Company