Thursday, May 16, 2024

Increasing the supply of transplantable organs, in the long term, and sooner.

 Here's an article on the website of The American Council on Science and Health, on technologies that might eventually replace the need for human organ transplants, and on policies to increase their supply while still needed.

We Urgently Need More Organs For Transplantation. Science And Policy Can Come To The Rescue. By Henry I. Miller, MS, MD and Sally Satel, MD

"Both scientific and policy advancements could provide desperately needed organs for transplantation. For example, there have been some promising early studies using kidneys from pigs genetically engineered to prevent rejection, but a policy change – paying human donors for donating organs – could be implemented immediately and would be a game changer.

...

"[A] sector of medicine that desperately needs breakthroughs is the transplantation of solid organs, which are in severely short supply. Currently, more than 100,000 Americans are waiting for transplants, and due to a shortage of hearts, lungs, livers, and kidneys, at least 17 die each day. Donor organs — from a living person or cadaver — must match the rejection recipient’s tissue type and size; they are often not perfect. By one estimate, approximately half of transplanted organs are rejected by recipients’ bodies within 10-12 years, despite a constantly expanding understanding of what causes rejection. Another obstacle is that the organ procurement system in the U.S. is inefficient, inconsistent, and unaccountable – in short, a mess that causes preventable deaths.

"We are making progress, but too slowly. Two new high-tech approaches to providing organs for transplantation might ultimately both eliminate the need for organ donors and reduce the risk of tissue rejection. And there is also a low-tech approach that would require only a tweak in healthcare policy.

"Organs produced by 3D bioprinting"

...

"Organs from genetically modified pigs"


...

"The low-tech policy approach

"Although friends and relatives and even the occasional “good Samaritan” donor can donate kidneys, they must be given without compensation. Under section 301(a) of the National Organ Transplant Act of 1984 (NOTA), it is a federal crime for “any person to knowingly acquire, receive, or otherwise transfer any human organ for valuable consideration for use in human transplantation if the transfer affects interstate commerce.”  Therefore, we propose a federal tax credit for living donors willing to save the life of a stranger. The value of the reward should be between $50,000 and $100,000, which physicians and others who endorse donor compensation believe would be sufficient to address the organ shortage. An economic analysis published in 2022 estimated that a reward of $77,000 could encourage sufficient donations to save 47,000 patients annually.

"The credit would be universally available—refundable in cash for people who do not owe income tax, not phased out at high-income levels, and available under the alternative minimum tax. NOTA’s restriction on payments by organ recipients and other private individuals and organizations would not change—it would still be illegal for recipients to buy organs.

"A qualified organ donation would be subject to stringent safeguards. As all donors are now, prospective compensated donors would be carefully screened for physical and emotional health. A minimum six-month waiting period before the donation would filter out impulsive donors and donations by financially desperate individuals seeking instant cash.

"In addition to saving lives, the credit would save the government money, perhaps as much as $14 billion per year, by reducing expenditures on dialysis. Thus, donors would receive financial compensation from the government for contributing to the public good and bearing the risk of a surgical operation to remove the organ.

"This would be a compassionate and pragmatic policy. Moreover, it could be implemented immediately, rapidly clearing much of the backlog of Americans waiting for organs in advance of the longer-term high-tech approaches.

"The organ shortage kills thousands of Americans every year. We must do all we can to alleviate it now."


HT: Frank McCormick

Wednesday, May 15, 2024

Interviews with school choice stakeholders

 Here's a paper about school choice in New Orleans, organized around interviews with New Orleans "Experts and Administrators" on the one hand and "Activists and Educators" on the other. 

Akchurin, Maria, and Gabriel Chouhy. "Designing Better Access to Education? Unified Enrollment, School Choice, and the Limits of Algorithmic Fairness in New Orleans School Admissions." Qualitative Sociology (2024): 1-43.

Abstract: "Economic sociologists have long recognized that markets have moral dimensions, but we know less about how everyday moral categories like fairness are reconciled with competing market principles like efficiency, especially in novel settings combining market design and algorithmic technologies. Here we explore this tension in the context of education, examining the use of algorithms alongside school choice policies. In US urban school districts, market design economists and computer scientists have applied matching algorithms to build unified enrollment (UE) systems. Despite promising to make school choice both fair and efficient, these algorithms have become contested. Why is it that algorithmic technologies intended to simplify enrollment and create a fairer application process can instead contribute to the perception they are reproducing inequality? Analyzing narratives about the UE system in New Orleans, Louisiana, USA, we show that experts designing and implementing algorithm-based enrollment understand fairness differently from the education activists and families who use and question these systems. Whereas the former interpret fairness in narrow, procedural, and ahistorical terms, the latter tend to evaluate fairness with consequentialist reasoning, using broader conceptions of justice rooted in addressing socioeconomic and racial inequality in Louisiana, and unfulfilled promises of universal access to quality schools. Considering the diffusion of “economic styles of reasoning” across local public education bureaucracies, we reveal how school choice algorithms risk becoming imbued with incommensurable meanings about fairness and justice, compromising public trust and legitimacy. The study is based on thirty interviews with key stakeholders in the school district’s education policy field, government documents, and local media sources."


"Designing and implementing algorithm-based UE systems entails complex moral and political considerations, including questions about how to operationalize what is fair when giving priority to some students over others. The designers and supporters of these systems argue that, by automating and randomizing assignments to oversubscribed schools, UE algorithms are not only efficient, but also impartial and, therefore, value-neutral. Yet as policy instruments, their use is explicitly predicated on normative grounds: centralized enrollment platforms seek to make choice more transparent and fair, which in practice means weakening the influence of social privileges in access to educational opportunities. But even if UE systems constitute powerful technologies that deliver simple and efficient enrollment across the board, providing greater access to school choice, is it possible that they still end up eroding public trust and contributing to the perception they are reproducing inequality? And if so, why?

,,,

"We argue that a crucial reason why technically irreproachable policy instruments like UE algorithms may fall short of eliciting sufficient moral consensus and become enmeshed in political disputes is that core values like fairness are defined and interpreted differently across the contexts where such instruments are created and used.

...

"We examine the multivalent meanings of algorithmic fairness through a study of OneApp, the unified enrollment system developed more than a decade ago in New Orleans, Louisiana (NOLA).Footnote1 Well-known as a national exemplar of market-based school reform, New Orleans is unique in that all the city’s public-school students now attend charter schools, a radical experiment widely celebrated by the school reform movement that has nevertheless elicited heated debate. Our study shows that a paradigmatic clash has emerged between how fairness in the enrollment process is understood “from above” and “from below.” Fairness tends to be interpreted in narrow, procedural, and ahistorical terms by education experts who design and shepherd UE through implementation, even if many do imbue UE with the normative purpose of limiting the influence of social privilege in access to school choice. By contrast, education activists tend to evaluate fairness with consequentialist reasoning and in terms of broader conceptions of justice rooted in addressing the history of socioeconomic and racial inequality in New Orleans, and the unfulfilled promise of access to quality schools for all. From a top-down perspective, then, UE algorithms are seen as a positive step towards making the school system a more equitable marketplace. In this view, an algorithm-based enrollment system plays a critical role in the democratization of choice. Seen from below by those left out, however, the same algorithms legitimize an inherently unjust market system where chance still determines (unequal) access to educational opportunity. Moreover, the fact that parents need to participate in an algorithmic process instead of directly enrolling their kids in a good-quality neighborhood school signals the absence of real equity.

...

"promoting choice options such as charter schools has yielded benefits to both students who enroll in them and—via competitive effects—those who attend schools nearby (Berends 2015; Jabbar et al. 2022) in some (but not all) cases. On the other hand, researchers have also warned that choice policies can exacerbate existing inequalities, insofar as access to valued information, social networks, and resources are crucial for capitalizing on the new opportunities that become available in a more competitive marketplace

...

“market design” is perhaps the specialization area that most enthusiastically embodies the “performative” aspect of economics practice—the idea that economists not only describe markets but also perform them through sociotechnical devices (Caliskan and Callon 2009; Callon 1998; MacKenzie and Millo 2003).  ... For too long, the design of “fair”, “efficient”, and “transparent” UE algorithms has remained a technical matter in the hands of experts, not an object of study worth analyzing from sociological, political, or even philosophical standpoints.

...

"Interviews consisted of a semi-structured component following an interview guide and a component relying on vignettes designed to compare how our interviewees conceptualize fairness across the same four scenarios. After the first part of the interview, we typically took turns reading vignettes aloud and asking the same set of follow-up questions to our respondents. For example, the first scenario describes Malcolm, a hypothetical student whose family uses OneApp to apply to elementary school and he gets his fifth-choice school, which is rated a C. We then ask respondents to evaluate whether Malcolm has been treated fairly, gradually adding new information about his socioeconomic status, racial background, and disability status.

...

"In this study, we do not rely on statistical sampling logic and do not seek to make generalizable claims about perceptions of fairness regarding OneApp among all administrators or all NOLA families using this UE system. Instead, we aim to show how studying an algorithmic tool reveals how experts and community leaders embedded in the same education policy field have different ways of conceptualizing and talking about fairness. 

...

"For instance, when we described the experience of a hypothetical student, Malcolm, whose parents used OneApp to apply to elementary school last year, many respondents rejected the notion of procedural fairness outright. In the scenario, Malcolm and his family had secured a spot in a school with the letter grade C that was their fifth preference. When we asked our respondents whether Malcolm had been treated fairly, one respondent from an education justice organization replied, “No, I don’t think it’s fair and it makes me wonder what is a better way because [the explanation we hear is], ‘We need more quality seats.’ I’m like, ‘Oh really? How are we going to get there?’ Because we want more quality seats” 

#########

The article goes on to point out that the school district hasn't published the algorithm code or flow charts, which adds to suspicions of unfairness.  My inclination is that such things should be in the public domain, which might help the discussion focus on the very different issues of how schools are assigned, and why not all schools are first rate.


Tuesday, May 14, 2024

Simulating European kidney exchange, by Druzsin, Biró, Klimentova, and Fleiner

There are a big variety of procedures used for kidney exchange in Europe.  Here are a set of simulations meant to explore their effects.

Druzsin, Kristóf, Péter Biró, Xenia Klimentova, and Rita Fleiner. "Performance evaluation of national and international kidney exchange programmes with the ENCKEP simulator." Central European Journal of Operations Research (2024): 1-21.

"we are aware of four international KEPs running worldwide:

  • Czech-Austrian-Israeli collaboration,

  • KEPSAT involving Italy, Portugal, Spain,

  • STEP, run by Scandiatransplant,

  • NZKX by Australia and New Zealand.

One of the main aspects that can differ in between international KEPs is collaboration polices. In KEPSAT each of the three countries conducts a national matching run first, and only after that they seek for international cycles in the remaining pools. The other three international KEPs merge their pools and conduct one single matching run."

#######

Not surprisingly, maximizing domestic kidney exchange first leaves only hard to match pairs, which limits the effectiveness of international cooperation.  A 2023 paper from Portugal reports that, since 2017, only three Portuguese pairs were matched in the KEPSAT program with Spain and Italy.

Tuesday, March 12, 2024

Monday, May 13, 2024

Talks to doctors and students in Italy

 I just returned from a busy trip to Italy, that began with a talk to physicians in Rome about kidney exchange, after which I moved on to talk to students in Padua.

Both were fun in different ways.  Here are some of the students gathered for a spritz after one of my talks in Padua.





Sunday, May 12, 2024

Richard Slayman: first recipient of pig kidney transplant dies after two months. (RIP)

 Here's the story from the Guardian:

Pig kidney ‘xenotransplant’ patient dies two months later. No indication that Richard ‘Rick’ Slayman’s receipt of genetically modified kidney caused his death, says Massachusetts transplant team

"The first recipient of a genetically modified pig kidney transplant has died about two months later, with the hospital that performed the surgery saying it did not have any indication the transplant was the cause.

...

"In a statement, Slayman’s family thanked his doctors. “Their enormous efforts leading the xenotransplant gave our family seven more weeks with Rick, and our memories made during that time will remain in our minds and hearts,” the statement said.

"They said Slayman underwent the surgery in part to provide hope for the thousands of people who need a transplant to survive. “Rick accomplished that goal and his hope and optimism will endure forever.”

"In April, New Jersey woman Lisa Pisano also received a genetically modified pig kidney as well as a mechanical pump to keep her heart beating.

########

I'm not aware of any medical journal reports so far on these transplants--reporting has just been by press release...

Saturday, May 11, 2024

Jim Simons (1938-2024)

 Jim Simons, the great investor and philanthropist of math and computer science, died yesterday.

Here's the announcement from the Simons Foundation.

Simons Foundation Co-Founder, Mathematician and Investor Jim Simons Dies at 86

And here's the NYT:

Jim Simons, Math Genius Who Conquered Wall Street, Dies at 86. Using advanced computers, he went from M.I.T. professor to multibillionaire. His Medallion fund had 66 percent average annual returns for decades.


Friday, May 10, 2024

Kidney exchange in Germany?

 A draft law to make kidney exchange legal in Germany, and to allow nondirected donation, is making some progress: here (with the help of Google Translate) is a news story on the proposed new law.

Living kidney donation should be made easier

"In order to reduce the organ shortage in Germany, Federal Health Minister Karl Lauterbach (SPD) wants to make living kidney donations easier. This emerges from a draft amendment to the Transplantation Act. The Star first reported.

"According to the draft, the previously prescribed “proximity ratio” for so-called cross donations will no longer apply in the future. To date, couples in which one person wants to donate a kidney to the other but this is not possible due to incompatibility are only allowed to “cross-donate” with another couple in a comparable situation if there is a close relationship between the couples. This is intended to prevent organ trafficking and commercialization.

"In the future, this cross donation could be made without proximity, thereby significantly expanding the circle of recipients. According to the draft bill, the donation should be anonymous and organized by transplant centers. The aim of anonymity is to prevent money from being paid for an organ.

"Anonymous kidney donations should also be possible in principle. In the future, people in Germany could donate a kidney for selfless reasons without knowing who it is going to. In countries like the USA, this option has existed for a long time."


HT: Dorothea Kubler