Kidney transplantation in adults: The kidney transplant waiting list in the United States

INTRODUCTION — As of September 2021, there were approximately 90,000 patients registered on the United Network for Organ Sharing (UNOS) kidney transplant waiting list in the United States. Of these patients, 56 percent were designated as being in an "active" status on the waitlist, or eligible for a transplant if a kidney is offered [1]. Registration on this list by individual transplant programs is required before a patient can be allocated a deceased-donor organ.

This topic reviews the composition of and access to the kidney transplant waitlist in the United States, as well as the management of patients while they await kidney transplantation.

The details of the allocation algorithm for deceased-donor kidneys and issues related to the evaluation of the kidney transplant candidate are discussed separately:

●(See "Kidney transplantation in adults: Organ sharing".)

●(See "Kidney transplantation in adults: Evaluation of the potential kidney transplant recipient".)

THE ACTIVE AND INACTIVE WAITING LIST — Candidates may be registered on the waiting list and accrue time towards deceased-donor kidney transplantation at any time after a diagnosis of irreversible kidney disease is made and the glomerular filtration rate (GFR) decreases to ≤20 mL/min. The GFR can be determined by any modality, including direct measurement or any of the available estimating equations. These include GFR-estimating equations that do not account for race, including the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. (See "Assessment of kidney function", section on 'Assessment of GFR'.)

For candidates ≥18 years old, the calculation of waiting time (which is used to prioritize candidates for kidney allocation) is based upon the earliest of the following:

●The date that the candidate starts regularly administered dialysis as a patient with end-stage kidney disease (ESKD)

●The registration date if the patient is predialysis and the measured or estimated GFR is ≤20 mL/min

●The date that the measured or estimated GFR becomes ≤20 mL/min if the patient is predialysis and was registered at a GFR >20 mL/min

Predialysis patients who are referred for transplantation with a GFR that is already ≤20 mL/min are not retroactively assigned waiting time to the date that their GFR became ≤20 mL/min. Thus, early referral of predialysis patients for transplant is important in order to maximize their waiting time.

For candidates <18 years old, waiting-list time begins either on the date of registration or the date of initiation of dialysis, whichever is earliest and regardless of the GFR [1].

Candidates may be on the active or "inactive" list. A candidate in active status is eligible for transplantation if a kidney is offered. A candidate in inactive status is temporarily unavailable or unsuitable for transplantation and cannot receive a deceased-donor organ offer. Candidates are placed in inactive status if an intercurrent condition develops that makes transplantation temporarily inadvisable, such as a treatable malignancy or infection. In contrast to "delisting," where a candidate is removed from the waitlist, patients in inactive status remain on the waitlist. Inactive patients continue to gain waiting time while in inactive status. Delisted patients regain their waiting time retroactively to their dialysis start date if placed back on the waiting list. Transplant programs are not obliged to maintain contact with delisted patients.

In November 2003, a United Network for Organ Sharing (UNOS) policy change was implemented to allow candidates to accrue waiting time indefinitely while in inactive status. This resulted in a steady increase in the number of waitlisted candidates in inactive status, who now comprise approximately 45 percent of the kidney waiting list [2]. In 2019, the most common reasons for inactive status among newly registered patients included incomplete work-up (69 percent), too well (7 percent), insurance issues (7 percent), too sick (7 percent), candidate choice (3 percent), weight inappropriate for transplant (3 percent), and candidate for living-donor transplant only (2 percent). Other reasons (all less than 1 percent) included medical noncompliance and substance abuse [3]. Approximately 25 percent of patients registered as waitlist inactive never convert to active status and either die or are removed from the waitlist [4].

If a candidate receives a transplant or dies, the registering transplant hospital must notify the Organ Procurement and Transplant Network (OPTN) within 24 hours so that the candidate is removed from the list.

KIDNEY WAITLISTING FOR MULTIORGAN TRANSPLANT CANDIDATES — Patients who require a kidney transplant performed simultaneously with another solid organ transplant, such as a liver, heart, or lung transplant, can be registered on the kidney waiting list under different criteria. The kidney waitlisting criteria were first implemented for simultaneous liver-kidney (SLK) transplantation on August 10, 2017. The criteria were designed to identify patients with kidney function impairment considered unlikely to recover function with a liver transplant alone. These criteria are discussed in detail elsewhere. (See "Kidney function and non-kidney solid organ transplantation", section on 'Eligibility criteria for SLK'.)

The transplant program must document in the candidate's medical record and in the United Network for Organ Sharing (UNOS) computer system that the criteria have been met. These criteria were established to comply with the Organ Procurement and Transplantation Network (OPTN) Final Rule, which specifies that allocation for organ transplants be based on standardized criteria. In addition, the criteria were developed to promote equitable kidney donor allocation in consideration of patients who are awaiting deceased-donor kidney transplantation alone and to guard against overutilization of kidney allografts in the liver transplant population.

Recognizing that some liver transplant patients not meeting the SLK transplant criteria will have sustained kidney function impairment and, in many cases, will be dialysis dependent after liver transplant alone, the OPTN policy also established a "safety net," in which a candidate with an GFR ≤20 mL/min or requiring dialysis between 60 and 365 days after liver transplantation is eligible for priority donor kidney allocation. Transplant programs must report in the UNOS computer system that a patient has met the safety net eligibility criteria and confirm once every 30 days for 90 consecutive days ongoing satisfaction of the eligibility criteria.

Short-term effects of the SLK criteria, analyzing trends two years after criteria implementation, were a decrease in the percentage of deceased-donor kidney transplants that were SLK (5.1 percent prepolicy to 4.3 percent postpolicy), interrupting a prepolicy annual trend of increasing numbers of SLK from 2009 to 2016 [5]. In addition, waiting list mortality for kidney after liver registrations decreased after policy implementation [5].

The SLK transplant criteria have now been extended to include simultaneous heart-kidney and lung-kidney transplants, with formal implementation on September 28, 2023. These criteria mirror the SLK transplant criteria; in addition, the safety net listing criteria in the event of sustained kidney function impairment after single organ transplant are identical to the liver safety net criteria.

DEMOGRAPHICS OF THE WAITING LIST — After years of steady growth in the size of the kidney transplant waiting list in the United States, the number of candidates registered for kidney transplant decreased in 2015 for the first time in over a decade [6]. This trend coincided with a lower number of new candidate registrations in 2015 and an increase in the number of deceased-donor kidney transplants performed per annum [1]. There has been an increase in the number of kidneys recovered from deceased donors, which has been primarily observed in donors aged 18 to 64 years and may be attributed, at least in part, to a rise in the number of deaths due to opioid overdose [3,7]. In addition, a new kidney allocation system (KAS) was introduced in the United States in December 2014, which includes a provision designed to increase the utilization of kidneys recovered for transplantation through local/regional allocation of kidneys with a kidney donor profile index (KDPI) score >85 percent. The KDPI is a metric of predicted graft survival and is a percentile rank of estimated graft survival relative to all deceased-donor kidneys recovered in the United States in the preceding year. Higher KDPI values are associated with shorter predicted graft survival. (See "Kidney transplantation in adults: Organ sharing", section on 'Kidney donor profile index (KDPI)'.)

The increase in deceased-donor transplantation cannot be entirely attributed to the KAS, as the number of deceased-donor kidney transplants performed annually in the United States was increasing even prior to the implementation of the KAS. Although the increase in transplant volume is noteworthy, the decrease in size of the waitlist is related to both waitlist removals and an increase in the number of transplants, mostly from deceased donors and, to a lesser extent, living donors [1,3]. In 2020, 36,157 candidates were added to the waiting list, whereas 36,831 were removed, representing 674 more waitlist removals than additions. Of waitlist removals, 22,817 were removed because of a kidney transplant, an increase of 3,757 transplants from 2016. The sobering reality is that only 62 percent of waitlist removals were due to receipt of a transplant, and the majority of waitlist removals otherwise were either due to patient death or candidates becoming too sick for transplantation [1]. Thus, despite an increase in the number of kidney transplants being performed in the United States, the supply of organs continues to be outpaced by the demand, and many patients who wait for a deceased-donor kidney transplant will never receive one.

Analysis of data provided by the Organ Procurement and Transplant Network (OPTN) yielded the following data [8]:

●The percentage of older candidates (defined as ≥65 years) has increased from 19 to 25 percent between 2011 and 2021, with a corresponding decrease in percentage of younger patients.

●African American patients account for approximately 32 percent of listed registrants; this is similar to their representation in the chronic dialysis population and is approximately threefold higher than their frequency in the general population. The ratio of White to African American listed registrants has remained unchanged over the last decade. The percentage of White candidates has decreased from 39 to 36 percent and that of Hispanic candidates has increased from 18 to 21 percent.

●Representation of males is approximately 20 percent greater than females.

●Blood group type O registrants consistently comprise more than 50 percent of the list, followed by type A (27 percent), type B (17 percent), and type AB (2 to 3 percent).

●The percentage of patients with diabetes has increased from 33 to 39 percent since 2011.

●Five percent of waitlisted candidates had a calculated panel reactive antibody (cPRA) of 80 to <98 percent, and 6 percent had a cPRA of 98 to 100 percent. The cPRA is an expression of the degree of predicted incompatibility to the donor pool and is derived by the number and type of preexisting antibodies to human leukocyte antigen (HLA) antigens. The higher the cPRA, the more difficult it is to find an acceptable donor kidney.

●The percentage of patients with a previous transplant awaiting retransplant has decreased from 16 percent of the waitlist in 2011 to 12 percent of the waitlist in 2021.

WAITING TIME — Waiting times continue to be long for a kidney transplant, but recent trends indicate that waiting times may be either stabilizing or decreasing. In 2009, 10 percent of waitlisted candidates at year-end were waiting five or more years; this percentage increased to 14 percent in 2019 but decreased to 13 percent in 2021 [3,8]. In 2021, 39 percent of deceased-donor kidney recipients were maintained on dialysis for over five years; by comparison, 51 percent of deceased-donor recipients in 2015 were on dialysis for over five years [3,6,9].

Certain candidates generally have a longer waiting time:

●The time to transplant varies among blood types. Blood groups O and B patients wait the longest. Based on Organ Procurement and Transplantation Network (OPTN) data, the deceased-donor kidney transplant rate for blood groups AB and A are approximately 25 per 100 patient-years and 35 per 100 patient-years, respectively, whereas the deceased-donor transplant rate for blood groups O and B is approximately 15 per 100 patient-years.

●Sensitized candidates (ie, those with increased panel reactive antibodies [PRAs]) have a longer waiting-list time (approximately twice that of nonsensitized candidates). Sensitized candidates have antibodies to human leukocyte antigen (HLA) antigens that are expressed on donor kidneys and are more likely to have a positive crossmatch to potential kidney donors. The antibodies develop as a result of blood transfusion, pregnancy, and prior failed transplants. As a group, previously transplanted patients waited approximately twice as long as those awaiting a first transplant because of allosensitization.

The new kidney allocation system (KAS) has improved transplant access for Black and Hispanic candidates, who now receive a percentage of deceased-donor kidney transplants proportionate to their representation on the waiting list [9]. It is known that there is limited expression of the A2 antigen on kidney endothelial cells, and blood type-incompatible kidney transplantation from a blood group A2 donor can be successfully performed with conventional immunosuppression [10,11]. Because blood type B is more common in underrepresented racial/ethnic groups, the KAS aimed to increase access to transplantation for blood type B candidates by allowing them to be eligible for blood type A2 donors. Although transplantation rates for Black and Hispanic candidates have improved since the KAS, this provision remains underutilized. An analysis performed 18 months following implementation of the KAS reported that only 18 percent of kidney transplant programs were willing to perform a transplant from a blood type A2 donor into a blood type B recipient [12]. This percentage increased to 25 percent by 2017, but nevertheless, blood type A2-incompatible transplants constituted only 9 percent of all deceased-donor transplants performed in blood type B recipients [13]. Furthermore, African American and Hispanic candidates with blood type B were not more likely to receive an A2-incompatible deceased-donor kidney in the post-KAS era compared with before the revised KAS was implemented [13].

Access to deceased-donor transplantation since the KAS has increased considerably for the most sensitized candidates, who have a calculated panel reactive antibody (cPRA) of 99 to 100 percent. These candidates now receive approximately 10 percent of deceased-donor kidney transplants compared with 2 percent before the KAS [9]. The new allocation policy appears to have disproportionately directed allocation of the highest-quality kidneys to these candidates; there has been a fourfold percentage increase in the highest-quality donors since the KAS, as measured by the KDPI, but no corresponding increase in donors predicted to have the shortest graft survival [14]. Nevertheless, the most highly sensitized candidates who have a cPRA higher than 99.9 percent have not benefited from the KAS and remain more likely to be removed from the waitlist or die than to receive a transplant [15]. (See "Kidney transplantation in adults: Organ sharing", section on 'Impact of revised policy'.)

On March 15, 2021, the United Network for Organ Sharing (UNOS) implemented a new system intended to reduce geographic disparities in deceased-donor kidney allocation [16]. This new system eliminated the construct of allocating kidneys to transplant centers within donation service areas, a geographical area that defines an organ procurement organization's catchment area, to one in which deceased-donor kidneys are offered first to transplant centers within 250 nautical miles of the donor hospital. Proximity points are also given to candidates based upon the distance between their transplant center and the donor hospital. Simulations project that transplant rates will increase for pediatric candidates, females, African American and Hispanic candidates, patients with more than five years of dialysis time, and those with cPRA of 80 to 99 percent [17]. The actual impact of the new system on transplant rates has not yet been reported.

DEATH ON THE WAITING LIST — Overall mortality on the waiting list is approximately 5 percent per year, with a higher estimate of 7 percent per year for patients with diabetes [2]. The death rate increases with age. For the years 2003 to 2013, the death rate was approximately 2 deaths per 100 waitlist years for patients 18 to 34 years of age, which increased progressively to 8 deaths per 100 waitlist years at risk for patients >65 years of age [2]. Patients who are in inactive status on the waitlist have approximately double the risk of death while waiting as candidates in active status [18].

Approximately one-half of the deaths on the waiting list occur in patients who are on inactive status. This has increased markedly over the last several years as compared with 30 percent of waiting-list deaths noted among those with inactive status in 2003 [19].

As compared with remaining on the waitlist, studies have shown that kidney recipients experience a higher risk of death in the early posttransplant period [20]. This risk decreases with time after transplant, and survival eventually favors transplantation over dialysis (see "Kidney transplantation in adults: Patient survival after kidney transplantation", section on 'Survival compared with dialysis'). The duration of time after transplant required to reach equivalent survival depends on a number of factors, including recipient age, donor type, and waiting time incurred prior to transplant [20-23].

ACCESS TO THE WAITING LIST — Deceased-donor transplantation requires access to the waiting list, which in turn requires access to a transplant center. Optimal outcomes occur when kidney transplantation is performed as early as possible after the development of advanced chronic kidney disease (CKD), preferably before dialysis is required (preemptive transplantation). Unfortunately, most CKD patients do not see a nephrologist until late in the disease course [24]. Thus, because of the prolonged wait for a kidney, preemptive transplantation from a deceased donor is only an option for a small proportion of patients with CKD. (See "Kidney transplantation in adults: Timing of transplantation and issues related to dialysis".)

A number of variables have been reported to inhibit timely referral to transplantation. These include [25]:

●Lower level of educational attainment

●Lower socioeconomic status

●Non-English-speaking background

●Underrepresented race

●Female sex

●Dialysis in for-profit or isolated dialysis units

●Certain medical diagnoses such as diabetes mellitus

●Obesity

To minimize delays, patient and professional education about the benefits of early referral for transplantation is critical. For predialysis patients, early referral provides an opportunity to determine if a living donor is available and if the donor work-up can be completed expeditiously. This may facilitate the performance of preemptive transplantation and avoid dialysis access placement. (See "Kidney transplantation in adults: Evaluation of the living kidney donor candidate".)

Early referral and listing also afford patients the possibility of being offered a zero-mismatch deceased-donor kidney. Potential recipients of zero-mismatch deceased-donor kidneys are given some priority in allocation. (See "Kidney transplantation in adults: Organ sharing".)

HEALTH CARE OF TRANSPLANT CANDIDATES — Deceased-donor transplantation is unique among surgical procedures in that it is an urgent procedure performed in an elective population. It is not possible to accurately determine when a given patient will be called for transplantation, and patients on the active transplant list can be called for a transplant at any time.

This unpredictability poses unique challenges for transplant programs, which need to ensure that large numbers of patients, most of whom are not under their direct care, are medically cleared for transplant at all times. Thus, it is imperative that the treating clinician keeps the transplant program apprised of clinically significant changes in the recipient’s health.

Routine health maintenance — Patients should be cared for according to best practices and published clinical practice guidelines.

In parallel, dialysis units, nephrologists, and the patients themselves must keep transplant programs apprised of major developments in the patients' health that could be relevant to their transplant candidacy and posttransplant management. (See "Kidney transplantation in adults: Evaluation of the potential kidney transplant recipient", section on 'Contraindications'.)

Cardiovascular testing — Patients with chronic kidney disease (CKD) have a higher cardiovascular risk compared with individuals who do not have CKD (see "Chronic kidney disease and coronary heart disease", section on 'Chronic kidney disease as an independent risk factor for CHD'). As such, most adult patients with CKD who are being evaluated for transplantation undergo some form of cardiovascular screening at the time of initial evaluation and periodically during the waitlist period (see "Kidney transplantation in adults: Evaluation of the potential kidney transplant recipient", section on 'Cardiovascular disease'). However, it is not clear whether screening asymptomatic patients prior to transplantation provides any benefit [26] or which method of screening is optimal [26].

UpToDate’s approach to cardiovascular screening at the time of initial evaluation for transplantation is discussed elsewhere. (See "Kidney transplantation in adults: Evaluation of the potential kidney transplant recipient", section on 'Cardiovascular disease'.)

The utility of periodic cardiovascular testing for waitlisted candidates has not been proven [26]. Transplant centers generally take into account the patient's pretest probability for coronary heart disease and risk for a major adverse cardiovascular event when deciding whether to screen asymptomatic candidates (see "Screening for coronary heart disease", section on 'Who should be screened?'). In our institution, we do not rescreen candidates who are on the waiting list with noninvasive tests until they approach the anticipated time of a kidney offer (generally within two years) or living donation is anticipated.

We select patients for rescreening based on the 2012 the American Heart Association (AHA)/American College of Cardiology (ACC) clinical practice guidelines, endorsed by the American Society of Transplant Surgeons, the American Society of Transplantation, and the National Kidney Foundation. We select for noninvasive stress testing asymptomatic kidney transplant candidates who have multiple coronary heart disease risk factors regardless of functional status [26]. However, the utility of periodic cardiovascular testing for waitlisted candidates is considered uncertain. Coronary heart disease risk factors were adapted from the 2007 Lisbon Conference on the Care of the Kidney Transplant Recipient [27] and include:

●Diabetes mellitus

●Prior cardiovascular disease

●More than one year on dialysis

●Left ventricular hypertrophy

●Age >60 years

●Hypertension

●Dyslipidemia

Although opinion based, the committee considered three or more risk factors to be a reasonable threshold to consider noninvasive stress testing. Nevertheless, it is reported that noninvasive stress testing has variable predictive discrimination for the detection of coronary artery disease, ranging from a positive predictive value of 0.29 to 0.86 and a negative predictive value of 0.24 to 0.98 [26].

The 2014 ACC/AHA guidelines for perioperative cardiovascular evaluation for noncardiac surgery incorporate the use of a multivariate risk prediction tool for an estimate of the risk of perioperative major adverse cardiac events [28] (see "Evaluation of cardiac risk prior to noncardiac surgery"). For those at low risk (<1 percent), noninvasive cardiac testing is not recommended. For those at higher risk, only those with unknown or poor functional capacity (<4 METS) and in whom further testing will impact decision making or perioperative care are recommended for pharmacologic stress testing. Patients who can achieve ≥4 METS are not recommended for preoperative cardiac testing.

Whether these recommendations are applicable to patients awaiting kidney transplantation is unclear. Dialysis patients may not exhibit typical cardiac symptoms, such as chest pain, despite active ischemia [29].

The practitioner is advised to view guidelines as recommendations, rather than as strict rules, and to combine them with clinical judgment. In addition, excessive reliance on noninvasive tests that are not sufficiently accurate to exclude significant coronary heart disease in high-risk candidates may engender a false sense of security [30].

Physical activity — The benefits of increased physical activity on all-cause and cardiovascular mortality are well established in the general population, although prospective studies in patients with CKD are lacking. However, mortality risks have been reported to be greatest for patients with severe limitations in either moderate or vigorous physical activity and lowest for patients who exercise regularly [31-34]. These data support the view that patients should be strongly encouraged to engage in frequent physical activity while waiting for a transplant. (See "Kidney transplantation in adults: Physical activity in kidney transplant recipients", section on 'Pretransplantation management'.)

Obesity and weight loss — Obesity may be a major concern in the evaluation of kidney transplant candidates and those on the waiting list, and patients are frequently requested or required to lose weight in order to be listed on the waitlist or maintain their active status (see "Kidney transplantation in adults: Evaluation of the potential kidney transplant recipient"). Many of these candidates are unable to do so and remain inactive on the waitlist. In one study of Organ Procurement and Transplant Network (OPTN)/United Network for Organ Sharing (UNOS) data from 2006 to 2012, the cumulative incidence of conversion to active status at six years among obese inactive candidates was 69 percent for those with a body mass index (BMI) <35 kg/m², 54 percent for a BMI 35 to 39.9 kg/m², 41 percent for a BMI 40 to 44.9 kg/m², and 28 percent for a BMI ≥45 kg/m² [35].

There is a growing body of evidence that, paradoxically, obesity might be beneficial for patients on dialysis [36] and that loss of weight in order to obtain a transplant might be detrimental to outcome. Much of the data supporting these contentions, however, come from database analysis [37], and specific recommendations for individual patients should be individualized. Data indicate that obese kidney transplant recipients have a lower risk of death compared with remaining on dialysis [38]. Thus, it should not be taken for granted that weight loss in obese transplant candidates will always be in their interest.

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Kidney transplantation".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword[s] of interest.)

●Basics topics (see "Patient education: Kidney transplant (The Basics)" and "Patient education: Planning for a kidney transplant (The Basics)")

SUMMARY

●General principles – Candidates may be registered and accrue time on the kidney transplantation waiting list at any time after a diagnosis of irreversible kidney disease is made and the glomerular filtration rate (GFR) decreases to ≤20 mL/min. Registration on this list by individual transplant programs is required before a patient can be allocated a deceased-donor organ. (See 'Introduction' above and 'The active and inactive waiting list' above.)

●Active versus inactive waiting list – Candidates may be on the active or inactive list. A candidate in active status is eligible for transplantation if a kidney is offered. A candidate who is in inactive status is considered temporarily unavailable or unsuitable for transplantation. (See 'The active and inactive waiting list' above.)

●Waiting time – The median time to transplant for new candidates is more than 4.5 years and even longer for patients with blood type O and B and for sensitized candidates who have antibodies to human leukocyte antigen (HLA) antigens that are expressed on donor kidneys. (See 'Waiting time' above.)

●Death on the waiting list – The overall mortality on the waiting list is approximately 5 percent per year, with a higher estimate of 7 percent per year for patients with diabetes. The death rate increases with age. Approximately one-half of the deaths on the waiting list occur in patients who are on inactive status. (See 'Death on the waiting list' above.)

●Access to the waiting list – A number of variables have been reported to inhibit timely referral to transplantation. These include lower level of educational attainment, lower socioeconomic status, non-English-speaking background, underrepresented race, female sex, dialysis in for-profit or isolated dialysis units, certain medical diagnoses such as diabetes mellitus, and obesity. (See 'Access to the waiting list' above.)

●Health care of transplant candidates – Patients on the active transplant list need to be medically ready to undergo transplantation at any time. Optimal, routine health care is important and should be performed according to best practices and published clinical practice guidelines. Patients should be encouraged to engage in frequent physical activity while waiting for a transplant. (See 'Health care of transplant candidates' above.)