By Edward Krudy
NEW YORK, Oct 15 (Reuters) – For Alvin Roth, joint winner of
the 2012 Nobel prize for economics, studying the economy is
about finding real-life solutions for real-life questions and
never more so than in a revolutionary new system to match kidney
donors with patients.
Roth and fellow laureate, the mathematician, Lloyd Shapley,
have seen their groundbreaking work used in such diverse areas
as matching up employers with job seekers, doctors with
residency programs, and students with schools.
But arguably its greatest impact has been matching kidney
donors to patients in a system that was first applied in New
England hospitals under the New England Program for Kidney
Exchange (NEPKE), a scheme Roth helped found in 2004-2005.
The computerized pairing of groups of donors and patients
that Roth’s models inspired has revolutionized the way kidney
transplants are handled in the United States and has actually
increased the possible number of transplants.
Throughout the United States nearly 2,000 patients have
received kidneys under the system developed on Roth and
Shapley’s models that would otherwise not have received them,
according to Ruthanne Hanto, who has worked with Roth since 2005
after being co-opted to manage NEPKE.
In 2003, the year before the system was implemented, there
were just 19 kidney transplants from live donors in the United
States nationally, said Hanto. That number rose to 34 when the
system was introduced in 2004. Last year it reached 443.
“The majority have been done with some kind of computer
matching,” said Hanto, who is now project manager of the United
Network for Organ Sharing (UNOS), a national kidney matching
organization that NEPKE operations were folded into.
UNOS administers a kidney pared donor program for the Organ
Procurement and Transplantation Network, a public-private
partnership established in 1984 that links all of the
professionals involved in the donation and transplantation
system.
“He (Roth) had a hand in having these nearly 2000
transplants occurring in some form, because without his initial
work none of the others would have been able to follow,” said
Hanto.
Before wide-scale kidney-pair donations, donors and patients
mostly worked through a single transplant center. A patient
would identify friends and family that were willing to donate.
But if those Kidney’s were not compatible with the patient the
transplant could not take place and they would have to go on the
waiting list for a deceased donor.
The system that Roth helped build uses complicated computer
algorithms that allows patients to effectively swap incompatible
donors with compatible ones from other donor-patient pairs. This
can be done with single or multiple pares or in chains of
unrelated donors and recipients.
Donors that were not used and were willing to donate to
someone they did not know were also not lost to the system as
they had been before, but could be matched up to other patients.
The system actually increases the number of kidney donations
that are possible because it means that only people who really
need deceased donors are given them while others are matched
with live donors.
“Paired kidney donation is one of the few things that has
happened in the recent decade or more that actually has come
along and said we are going to get more kidney transplants into
the system,” said Richard Formica, medical director of the
kidney transplant program at Yale University.
Formica, who has worked on a committee called the kidney
paired donation workgroup with Roth for about a year, says that
with pared donations the number of transplants could rise from
between 1,500 and 2,500 a year on top of the 15,000 transplants
currently undertaken in the United States.
Formica also points out that because more people are able to
have live donor transplants fewer have to return for second
transplants as kidneys from live donor tend to last longer.
“His algorithm allows us to see combinations that you
wouldn’t see,” said Formica. “It revolutionized the way we do
it.”
Roth’s award is a reminder of kind of hands on work done by
some economists that can often remain in the background while
most of the attention focuses on economists who tackle the big,
global policy issues du jour, such as eurozone debt crisis and
the financial meltdown.
“Economics is about the real world,” Roth told Reuters
shortly after finding out he had won the Nobel prize. “We are
interested in how people lead their lives and like to think of
economics as being not just a social science but a humanity.”
Roth works in a little known field known as market design
that he affectionately describes as modeling the various
“courtships” that occur when choice is not free, but depends on
a second element in a pair.
Both Formica and Hanto describe Roth as a man who is both
highly intelligent and good a describing his ideas in a way
people can follow.
“Al is great to work with. Obviously he is highly
intelligent, but very down to earth, which I think is a great
combination,” said Hanto. “He is obviously very good at building
a theory, but then taking that theory and putting into practice
and looking at the practical implications of it.”
For Hanto, the challenge now is uniting the three national
kidney pair donor systems into one unified system.
(Editing by Andre Grenon)
