Unequal Racial Access to Kidney Transplantation, 46 Vanderbilt Law Review 805 (1993) (with Laura Dooley and Robert Gaston)
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  1. INTRODUCTION ........................................................ 806
  2. ANTIGEN MATCHING .................................................... 813
    1. The UNOS Policies for Mandated Sharing of Well-Matched Kidneys ... 813
      1. An Introduction to Antigen Compatibility ..................... 815
      2. Mandatory National Sharing of Six-Antigen-Matched Kidneys .... 817
      3. The Mandatory Local Point System ............................. 818
    2. The Costs of Matching: Disparate Access to Cadaveric Kidneys ..... 820
    3. The Disappearing Benefits of Matching ............................ 825
      1. Racial Differences in Transplant Survival .................... 826
      2. The Benefits of Six-Antigen Matching ......................... 830
      3. The Attenuated Benefits of Partial Antigen Matching .......... 831
      4. The Impact of New Immunosuppressant Drug Therapies ........... 833
  3. TRAGIC CHOICES ...................................................... 836
    1. The Limits of Two Simple Objectives .............................. 837
    2. The Relevance of Race ............................................ 841
    3. Proposal to Revise the UNOS Point System ......................... 843
      1. Accommodating Equity and Efficiency .......................... 843
      2. Defining the Geographic Scope of the Point System ............ 847
    4. Adapting Allocation to New Drug Therapies ........................ 849
    5. A Political History of Antigen Matching and Immunosuppression .... 850
  4. THE PLAUSIBILITY OF A DISPARATE IMPACT CHALLENGE .................... 853
    1. Disparate Impact of Kidney Allocation and Title VI Relief ........ 854
    2. Enforcement ...................................................... 858
  5. CONCLUSION .......................................................... 860
  6. APPENDIX: ESTIMATING THE DISPARATE IMPACT OF THE O RULE ............. 862

I. INTRODUCTION

Access to medical care is an issue of acute and increasing importance in the United States, a country in which the most promising of ground-breaking technologies may be available to only the privileged few. Although debate about the problem of unequal access to medical care typically centers on financial obstacles to advanced therapies and the obvious inequity of allowing patients' ability to pay to drive treatment decisions, issues of equitable access for patients of both genders and all racial and ethnic backgrounds increasingly have come into focus.

These concerns about equitable access animate the ongoing debate about how government should regulate the transplantation of kidneys. More than 100,000 people in the United States suffer from kidney failure-what doctors call "end-stage renal disease" (ESRD). While kidney failure may be treated with dialysis, kidney transplantation is the preferred treatment: studies show that transplant recipients are more likely to return to work, avoid hospitalization, and enjoy a greater sense of well-being than patients on dialysis. Kidney transplants constitute more than three-fourths of the solid organ transplants performed in this country and have success rates routinely as high as eighty percent. A severe shortage of transplantable kidneys, however, limits the availability of this preferred treatment.

For example, in 1990, while more than 18,000 Americans were registered on waiting lists, fewer than 8200 received renal transplants.

Federal regulations control the allocation of scarce donated kidneys among prospective recipients. Since 1972, Medicare has covered the costs of virtually all kidney transplants. To qualify for Medicare reimbursement, transplanting hospitals must abide by rules promulgated by the federal Organ Procurement and Transplantation Network (OPTN). Current OPTN policies for cadaveric kidney allocation give strong preference to potential recipients who are genetically similar to the donor as determined by the identification of antigens located on the surface of cells. For example, if a harvested kidney has all the same antigens as a potential recipient on the waiting list, then that patient will receive the kidney-even if other dialysis patients have waited longer for a transplant.

The rationale for basing kidney allocation on "antigen matching" is that a recipient who receives a kidney from a donor with similar antigens may be less likely to have her immunologic system reject it. The federal guidelines reflect a belief that better antigen matching will lead to a higher rate of kidney graft survival and that this interest in maximizing transplant outcomes should outweigh the equitable claims of patients who must wait longer for a renal allograft.

Mandated antigen matching, however, also makes it difficult for black dialysis patients to qualify for the pool of scarce cadaveric kidneys. Blacks wait almost twice as long as whites for their first transplant-13.9 and 7.6 months respectively. While whites comprise sixty-one percent of the dialysis population, they receive seventy-four percent of the kidney transplants. In a given year white dialysis patients have approximately a seventy-eight percent higher chance of receiving a cadaveric transplant than black dialysis patients.

The antigen matching rules are a "but for" cause of this racial disparity. Because antigens are distributed differently among racial groups, a white patient is more likely than a black patient to have antigens that match those on a kidney from a white donor. Whites donate almost ninety percent of kidneys in the United States. Because the proportion of blacks on the waiting list is significantly higher than the proportion of kidneys donated by blacks, white patients are more likely to have antigens that match those on donated kidneys. Thus, a disproportionately black waiting list chases a disproportionately white donor pool.

Alternative allocation rules could eliminate the racial disparity in access to donated kidneys. A first-come-first-served rule, for example, would give all patients equal access to the pool of cadaveric kidneys. Several scholars have argued that the best solution to racial disparity in transplantation is to increase black donation of both cadaveric and living related kidneys. They point out that blacks are less likely than whites to donate both cadaveric and living related kidneys. From this they suggest that increasing black donation rates could improve the pool of well- matched kidneys for blacks on the waiting list and thus mitigate the disparate effects of antigen matching rules.

Intensified efforts to increase the donation rates of black Americans, however, have virtually no chance of eliminating the disparate rates of transplantation for blacks and whites. Because the waiting list for kidney transplants is so disproportionately black, increasing the rate of black donation cannot plausibly equalize the proportions of blacks seeking and receiving kidneys. The incidence of ESRD in the United States is nearly four times greater for blacks than whites: while blacks comprise nearly twelve percent of the general population, thirty-four percent of ESRD patients are black. To eliminate the disparate impact of antigen matching, blacks would need to donate enough additional kidneys so that the proportion of black donors would approximate the proportion of blacks on the waiting list-thirty-four percent. To accomplish such an increase, the donation rate for blacks-for both cadaveric and living related organs-would have to increase to five times its current rate and more than four times the current rate for whites. Increases of this magnitude are unlikely. Efforts to increase black donation are laudable and important, but it is misleading to argue that increasing black donation rates could significantly reduce disparate racial access to transplantation.

This Article explores whether the disparate racial impact of mandated antigen matching is justified by higher overall survival rates of kidney transplants. Recent advances in the use of drugs that effectively suppress immune responses have dramatically altered the impact of antigen matching-the likelihood of graft survival may now be relatively independent of the degree of antigen matching. Our tentative conclusion is that technological advances have made antigen- based allocation less critical to transplant success.

Normatively, we argue that the equitable claims of black dialysis patients for cadaveric kidneys outweigh the marginal improvement in transplant outcomes currently associated with matching. Guido Calabresi and Philip Bobbitt have reasoned:
[C]orrected egalitarianism ... plays an unusually influential role in the American concept of equality. It accepts the general premise of formal egalitarianism that discrimination is proper so long as likes are treated alike, but corrects the operation of this premise by rejecting it whenever methods applying it happen to produce results which correlate the permissible category of discrimination-health, for example-with an impermissible one, such as wealth or race.

The federally mandated system for allocating kidneys has produced just this impermissible effect based on an increasingly weak correlation with health or transplant survival. Recent proposals to expand the influence of antigen matching on organ allocation would further increase racial disparity in transplantation. While the disparate racial impact of antigen matching has been intensely analyzed within the transplant community in the last two years, it has been largely ignored in the legal literature.

The Article also serves as a case study of the difficulty of administering regulations in the face of conflicting and evolving empirical data. The increased demand for donor organs has intensified debate over allocation, but the issues are not new. While some within the transplant community argue that allocation based on antigen matching is the most scientifically sound method, others contend that factors such as newer drug therapies, evolving technology, and equitable access are of greater importance. In the absence of firm empirical results, one of the most important normative choices will be allocating burdens of proof-because without certain knowledge about the benefits of antigen matching or new drug therapies, much will turn on presumptions.

The time is now ripe to consider these issues. While the allocation system was originally developed without the procedural protections of the Administrative Procedure Act, the Department of Health and Human Service (HHS) has decided to develop and submit for comment a notice of proposed rulemaking to replace the mandatory allocation system devised by UNOS. HHS expects to publish proposed allocation rules in the Federal Register in the near future. This procedural change may give those concerned with inequitable racial allocation an opportunity to overcome regulatory inertia.

Part II of this Article provides the factual background. There, we describe in more detail the federal rules governing antigen matching and the reasons why these rules cause disparate racial access to cadaveric kidney transplants. We also explore the degree to which antigen matching improves the likelihood of successful transplantation-focusing on newer immunological therapies that increasingly may divorce graft survival from antigenic similarity.

Part III explores difficult normative issues of kidney allocation. In our effort to justify a system that devalues antigen matching, we consider the ethical choices that must be made-implicitly or explicitly-in choosing one system of allocation over another. In particular, we pose in concrete terms the tradeoff between enhanced graft survival and equitable allocation of available kidneys. We propose specific allocation rules that seek to strike a more appropriate ethical and clinical balance.

Finally, Part IV examines the potential viability of a suit challenging the current regulations on a disparate impact theory. It should be emphasized that here, as in other contexts, the presence of disparate racial outcomes should not be taken to imply racial animus or bigotry on the part of any of the relevant advocates or decisionmakers. To the contrary, it is our firm belief that there is a surfeit of good faith among the various actors in the transplant community. The differences of opinion are inevitable and, indeed, a healthy byproduct of thoughtful responses to these complex and important issues.


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