Saturday, February 24, 2007

Kidney Allocation and Age

UNOS held a public forum on proposed changes to the kidney allocation system on February 8, 2007, in Dallas. For those who didn't attend, the slides presented at the meeting are available, as well as a more understandable but narrowly-focused summary from the PKD Foundation. Approximately 200 people attended in person and an additional 150 attended by web conference or phone, and they had a lot to talk about.

The proposed change that has been focused on the most is incorporating age into the allocation system. To be specific, the changes would incorporate the age of adult candidates as one factor in prioritizing the allocation of standard criteria donor (SCD) kidneys. All of those qualifiers are important, since reading most accounts could lead people to believe:

  • that older age doesn't currently play a factor in candidacy for transplantation (it does, in evaluating and deciding to list patients for transplant),
  • that younger age isn't currently used in the allocation system (it is, in that children are given extra "points" in the current system),
  • that all kidneys available will be allocated through this system (they won't, since expanded criteria donor [ECD] kidneys will be allocated purely on waiting time), or
  • that age will be the only factor used in allocation (it won't be, it will be one of many factors).

The current system strives to be as fair as possible. Fairness coexists with utility, which depends on "matching" donors and recipients into combinations most likely to have the best outcomes. Over the years, the importance of "matching" based on HLA antigens has decreased, but the logic of matching based on age is still solid. A 25-year-old kidney in a 75-year-old patient is likely to outlive its recipient, still having years of potential function when the recipient dies of other causes. The current system has no way to account for this form of "matching." Kidneys from donors over the age of 60 are considered expanded criteria donor (ECD) kidneys, as well as those from donors over the age of 50 with less-than-ideal conditions. While these kidneys may be less likely to last for decades than standard critera donor (SCD) kidneys, older recipients are also often less likely to live as long, which lessens the chance that donated kidneys will outlive their recipients. ECD kidneys will still be allocated primarily by waiting time, so older recipients will still be able to receive kidneys based on their waiting time, kidneys that could likely work well for them.

Most of the news coverage of this story seems to be from Chicago, starting with an article in the Chicago Tribune the morning after the public forum. The article is clear and reasonably balanced, though a bit opposed. Two patients with polycystic kidney disease were interviewed for the article--Jack Fassnacht wondering if the new proposal is "suggesting the life of a 30-something has more value than the life of a 50-something" and Norma Knowles asking ""Who's to say an older person's five years of life are any less important than a younger person's nine years?" Both of these are impossible questions to answer, and the new proposal is NOT attempting to answer them. It measures each additional year of adult life as equal, whether your 20th, 50th, or 80th, basing its priority on whether one is likely to see that year. Some are wondering whether UNOS is valuing one person's 30th year over another's 70th year, which is dicey, but the converse of valuing one person's 70th year over another's 30th year is even less justifiable.

These issues were more recently tackled in a Chicago Sun-Times column by Sue Ontiveros. She presents a much firmer defense of the advantages of the current system and those advantaged by it. She argues:

  • that "the person who most needs a new kidney is selected first" (unlikely, since there are no measures of "need" or medical urgency in the current system),
  • that a new system could later incorporate gender or race (these factors have been analyzed and excluded), and
  • that "no one has said that the current criteria for choosing kidney transplant recipients isn't working." (very unlikely, since someone is always saying that the current criteria aren't working!).

Most flabbergasting to me is that she argues that the proposed change is "telling people it pays to be young and ill" and not "rewarding" her for maintaining the function of her native kidneys. First, I don't know of anyone with kidney disease who would think "hey, if my kidneys fail sooner, I'll have a better chance of getting a new one!" Accusations of personal responsibility cut both ways, when those that have congenital or immunologic diseases consider diabetes and hypertension to be purely the result of lifestyle. I think it's fairer to say that end-stage organ failure is a crisis under any circumstances. Second, native kidney function is far better than living with a transplant, so the reward that Ms. Ontiveros gets for her good habits is better health today, which I'm sure that anyone on the transplant list would be extremely envious of.

Ultimately, this debate makes some people angry, but it makes me rather sad. I may feel that transplanting a 20-year-old is a better use of a kidney than giving it to a 80-year-old, but could I look an 80-year-old in the eye and tell them that they don't "deserve" a kidney? That's much harder. UNOS has calculated that the proposed changes will result in an additional 11,457 years of life from kidney transplants than the current system. This is an impressive statistic, but what it tells me is that at least 11,457 years of life are lost to kidney disease, and probably far more than that. The supply of donor organs is extremely limited, and any improved system will still face this incredible shortfall and the faces of those who could benefit from transplantation but haven't had the chance to.


moreena said...

You make some really thoughtful points. And bravo to you for calling the reporter on playing the blame game again when it comes to illness.

gleasonjim said...

Manu, what an excellent commentary you write, so different than many we see on this very controversial issue in terms of logic and balance. Thanks for posting the link on the transplant listserv so we could find you. I will pass the link along to some others very interested in this issue and encourage you to keep up the good work of your excellent web site.

Ann S. said...

I'm 70 and have failing kidneys. My attitude is that I've lived my life and a younger person should be ahead of me in line. Not that I'd choose to die anytime soon, but dying of kidney failure is probably better than getting Alzheimer's.