Kidney Paired Donation Chains Initiated by Deceased Donors

Introduction

Rather than generating 1 transplant by directly donating to a candidate on the waitlist, deceased donors (DDs) could achieve additional transplants by donating to a candidate in a kidney paired donation (KPD) pool, thereby, initiating a chain that ends with a living donor (LD) donating to a candidate on the waitlist. We model outcomes arising from various strategies that allow DDs to initiate KPD chains.

Methods

We base simulations on actual 2016 to 2017 US DD and waitlist data and use simulated KPD pools to model DD-initiated KPD chains. We also consider methods to assess and overcome the primary criticism of this approach, namely the potential to disadvantage blood type O-waitlisted candidates.

Results

Compared with shorter DD-initiated KPD chains, longer chains increase the number of KPD transplants by up to 5% and reduce the number of DDs allocated to the KPD pool by 25%. These strategies increase the overall number of blood type O transplants and make LDs available to candidates on the waitlist. Restricting allocation of blood type O DDs to require ending KPD chains with LD blood type O donations to the waitlist markedly reduces the number of KPD transplants achieved.

Conclusion

Allocating fewer than 3% of DD to initiate KPD chains could increase the number of kidney transplants by up to 290 annually. Such use of DDs allows additional transplantation of highly sensitized and blood type O KPD candidates. Collectively, patients of each blood type, including blood type O, would benefit from the proposed strategies.

Life and expectations post-kidney transplant: a qualitative analysis of patient responses

BACKGROUND

The effect of a kidney transplant on a recipient extends beyond the restoration of kidney function. However, there is limited qualitative analysis of recipient perspectives on life following transplantation, particularly in the United States. To understand the full patient experience, it is necessary to understand recipient views on life adjustments after kidney transplantation, medical management, and quality of life. This could lead to improvements in recipient care and sense of well-being.

METHODS

We conducted a paper-based survey from March 23 to October 1, 2015 of 476 kidney transplant recipients at the University of Michigan Health System in Ann Arbor, Michigan. We analyzed their open-ended responses using qualitative research methods. This is a companion analysis to a previous quantitative report on the closed-ended responses to that survey.

RESULTS

Common themes relating to changes following transplantation included: improvements in quality of life, a return to normalcy, better health and more energy. Concerns included: duration of graft survival, fears about one day returning to dialysis or needing to undergo another kidney transplant, comorbidities, future quality of life, and the cost and quality of their healthcare. Many recipients were grateful for their transplant, but some were anxious about the burdens transplantation placed on their loved ones.

CONCLUSIONS

While most recipients reported meaningful improvements in health and lifestyle after kidney transplantation, a minority of participants experienced declines in energy or health status. Worries about how long the transplant will function, future health, and cost and quality of healthcare are prevalent. Future research could study the effects of providing additional information, programs, and interventions following transplantation that target these concerns. This may better prepare and support kidney recipients and lead to improvements in the patient experience.

KPDGUI: An interactive application for optimization and management of a virtual kidney paired donation program

BACKGROUND AND OBJECTIVES

The aim in kidney paired donation (KPD) is typically to maximize the number of transplants achieved through the exchange of donors in a pool comprising incompatible donor-candidate pairs and non-directed (or altruistic) donors. With many possible options in a KPD pool at any given time, the most appropriate set of exchanges cannot be determined by simple inspection. In practice, computer algorithms are used to determine the optimal set of exchanges to pursue. Here, we present our software application, KPDGUI (Kidney Paired Donation Graphical User Interface), for management and optimization of KPD programs.

METHODS

While proprietary software platforms for managing KPD programs exist to provide solutions to the standard KPD problem, our application implements newly investigated optimization criteria that account for uncertainty regarding the viability of selected transplants and arrange for fallback options in cases where potential exchanges cannot proceed, with intuitive resources for visualizing alternative optimization solutions.

RESULTS

We illustrate the advantage of accounting for uncertainty and arranging for fallback options in KPD using our application through a case study involving real data from a paired donation program, comparing solutions produced under different optimization criteria and algorithmic priorities.

CONCLUSIONS

KPDGUI is a flexible and powerful tool for offering decision support to clinicians and researchers on possible KPD transplant options to pursue under different user-specified optimization schemes.

Comparison of patient and provider goals, expectations, and experiences following kidney transplantation

OBJECTIVE

This study examined whether kidney transplant recipients' post-transplant goals and expectations align with those as perceived by their healthcare providers.

METHODS

Post-transplant goals and expectations across four domains were assessed via a descriptive survey of healthcare providers (N=72) and kidney transplant recipients (N=476) at the University of Michigan from March 23 - October 1, 2015. Demographic and transplant-related data were collected via a retrospective review of medical records, and survey responses were compared using Chi-square tests, Wilcoxon two-sample tests, and logistic regression.

RESULTS

Patients expressed higher quality of life (mean Neuro-QOL T-score 60.2 vs. 52.7), were less likely to report that they were currently experiencing complications (11% vs. 24%), and anticipated their transplants to last longer (median 25 vs. 15 years) and to live longer (median 80 vs. 71 years) than providers expected for their typical patient. However, provider perceptions of patients' future ability to feel well, perform daily activities and work were significantly higher than those expressed by patients (all p<0.05).

CONCLUSION

Kidney transplant patient and provider expectations differ in significant ways.

PRACTICE IMPLICATIONS

Identified areas of discordance may provide opportunities for patients and providers to better evaluate treatment option tradeoffs in post-transplant clinical interactions.

Secular Trends in the Cost of Immunosuppressants after Solid Organ Transplantation in the United States

BACKGROUND AND OBJECTIVES

Immunosuppressive medications are critical for maintenance of graft function in transplant recipients but can represent a substantial financial burden to patients and their insurance carriers.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

To determine whether availability of generic immunosuppressive medications starting in 2009 may have alleviated some of that burden, we used Medicare Part D prescription drug events between 2008 and 2013 to estimate the average annualized per-patient payments made by patients and Medicare in a large national sample of kidney, liver, and heart transplant recipients. Repeated measures linear regression was used to determine changes in payments over the study period.

RESULTS

Medicare Part D payments for two commonly used immunosuppressive medications, tacrolimus and mycophenolic acid (including mycophenolate mofetil and mycophenolate sodium), decreased overall by 48%-67% across organs and drugs from 2008 to 2013, reflecting decreasing payments for brand and generic tacrolimus (21%-54%), and generic mycophenolate (72%-74%). Low-income subsidy payments, which are additional payments made under Medicare Part D, also decreased during the study period. Out-of-pocket payments by patients who did not receive the low-income subsidy decreased by more than those who did receive the low-income subsidy (63%-79% versus 24%-44%).

CONCLUSIONS

The decline in payments by Medicare Part D and by transplant recipients for tacrolimus and mycophenolate between 2008 and 2013 suggests that the introduction of generic immunosuppressants during this period has resulted in substantial cost savings to Medicare and to patients, largely reflecting the transition from brand to generic products.

A Kidney Graft Survival Calculator that Accounts for Mismatches in Age, Sex, HLA, and Body Size

BACKGROUND AND OBJECTIVES

Outcomes for transplants from living unrelated donors are of particular interest in kidney paired donation (KPD) programs where exchanges can be arranged between incompatible donor-recipient pairs or chains created from nondirected/altruistic donors.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Using Scientific Registry of Transplant Recipients data, we analyzed 232,705 recipients of kidney-alone transplants from 1998 to 2012. Graft failure rates were estimated using Cox models for recipients of kidney transplants from living unrelated, living related, and deceased donors. Models were adjusted for year of transplant and donor and recipient characteristics, with particular attention to mismatches in age, sex, human leukocyte antigens (HLA), body size, and weight.

RESULTS

The dependence of graft failure on increasing donor age was less pronounced for living-donor than for deceased-donor transplants. Male donor-to-male recipient transplants had lower graft failure, particularly better than female to male (5%-13% lower risk). HLA mismatch was important in all donor types. Obesity of both the recipient (8%-18% higher risk) and donor (5%-11% higher risk) was associated with higher graft loss, as were donor-recipient weight ratios of <75%, compared with transplants where both parties were of similar weight (9%-12% higher risk). These models are used to create a calculator of estimated graft survival for living donors.

CONCLUSIONS

This calculator provides useful information to donors, candidates, and physicians of estimated outcomes and potentially in allowing candidates to choose among several living donors. It may also help inform candidates with compatible donors on the advisability of joining a KPD program.

Why do we have the kidney allocation system we have today? A history of the 2014 kidney allocation system

"Those who do not know the past are destined to repeat it". The current system for the allocation of deceased donor kidneys that was implemented in December 2014 (termed the kidney allocation system (KAS)) was the culmination of a decade-long process. Thus, many people involved in transplantation today may not be aware of the underlying concepts and early debates that resulted in KAS. Others who were involved might not remember the details (or have chosen to forget). The goal of this manuscript is to outline the history of the process in order to shed light on why KAS has its current format.

Utilization of Deceased Donor Kidneys to Initiate Living Donor Chains

We propose that some deceased donor (DD) kidneys be allocated to initiate nonsimultaneous extended altruistic donor chains of living donor (LD) kidney transplants to address, in part, the huge disparity between patients on the DD kidney waitlist and available donors. The use of DD kidneys for this purpose would benefit waitlisted candidates in that most patients enrolled in kidney paired donation (KPD) systems are also waitlisted for a DD kidney transplant, and receiving a kidney through the mechanism of KPD will decrease pressure on the DD pool. In addition, a LD kidney usually provides survival potential equal or superior to that of DD kidneys. If KPD chains that are initiated by a DD can end in a donation of an LD kidney to a candidate on the DD waitlist, the quality of the kidney allocated to a waitlisted patient is likely to be improved. We hypothesize that a pilot program would show a positive impact on patients of all ethnicities and blood types.

Efficacy of plasmapheresis on donor-specific antibody reduction by HLA specificity in post-kidney transplant recipients

BACKGROUND

Donor-specific antibodies (DSAs) to HLA antigens can cause acute antibody-mediated rejection (AMR) after kidney transplantation (Txp). Therapeutic plasma exchange (TPE) has been used for AMR treatment; however, DSA reduction rates are inconsistent. We investigated DSA reduction rates by HLA specificity and clinical outcome.

STUDY DESIGN AND METHODS

Sixty-four courses of TPE for 56 kidney Txp recipients with high DSA were investigated. Dates of TPE procedures and Txp, patients' age, sex, race, creatinine (Cr), and mean fluorescent intensity (MFI) of DSA were retrieved. MFI reduction rate after one to three TPE and four to six TPE procedures were calculated by HLA DSA specificity in each patient, and the mean reduction rates were compared. The relationship of TPE treatment, MFI or Cr improvement rate, and graft age was also investigated.

RESULTS

Patients received a mean 6.0 TPE procedures. Most received intravenous immunoglobulin after TPE and immunosuppressives. Forty-two cases (65.6%) had DSA to HLA Class I and 54 cases (84.4%) to Class II, including 32 cases (50.0%) to both. Mean MFI reduction rates after one to three TPE and four to six TPE procedures were 25.7 and 37.1% in HLA Class I, 25.1 and 34.2% in Class II, and 14.3 and 19.9% in DR51-53. The mean Cr improvements at the end of TPE and 3 and 6 months after TPE were 3.41, -0.37, and -0.72%, respectively.

CONCLUSION

Six TPE procedures decreased DSA more than three TPE procedures, but reduction rate was lower by the second three TPE procedures than the first three TPE procedures. Although the mean Cr improvement was minimal, the treatment has good potential to stop further deterioration of kidney function. Better Cr improvement rate is correlated with the graft age.

Patient selection and volume in the era surrounding implementation of Medicare conditions of participation for transplant programs

OBJECTIVE

To evaluate evidence of practice changes affecting kidney transplant program volumes, and donor, recipient and candidate selection in the era surrounding the introduction of Centers for Medicare and Medicaid Services (CMS) conditions of participation (CoPs) for organ transplant programs.

DATA

Scientific Registry of Transplant Recipients; CMS ESRD and Medicare claims databases.

DESIGN

Retrospective analysis of national registry data.

METHODS

A Cox proportional hazards model of 1-year graft survival was used to derive risks associated with deceased-donor kidney transplants performed from 2001 to 2010.

FINDINGS

Among programs with ongoing noncompliance with the CoPs, kidney transplant volumes declined by 38 percent (n = 766) from 2006 to 2011, including a 55 percent drop in expanded criteria donor transplants. Volume increased by 6 percent (n = 638) among programs remaining in compliance. Aggregate risk of 1-year graft failure increased over time due to increasing recipient age and obesity, and longer ESRD duration.

CONCLUSIONS

Although trends in aggregate risk of 1-year kidney graft loss do not indicate that the introduction of the CoPs has systematically reduced opportunities for marginal candidates or that there has been a systematic shift away from utilization of higher risk deceased donor kidneys, total volume and expanded criteria donor utilization decreased overall among programs with ongoing noncompliance.

Decision Making in Kidney Paired Donation Programs with Altruistic Donors

In recent years, kidney paired donation (KPD) has been extended to include living non-directed or altruistic donors, in which an altruistic donor donates to the candidate of an incompatible donor-candidate pair with the understanding that the donor in that pair will further donate to the candidate of a second pair, and so on; such a process continues and thus forms an altruistic donor-initiated chain. In this paper, we propose a novel strategy to sequentially allocate the altruistic donor (or bridge donor) so as to maximize the expected utility; analogous to the way a computer plays chess, the idea is to evaluate different allocations for each altruistic donor (or bridge donor) by looking several moves ahead in a derived look-ahead search tree. Simulation studies are provided to illustrate and evaluate our proposed method.

Dynamic challenges inhibiting optimal adoption of kidney paired donation: findings of a consensus conference

While kidney paired donation (KPD) enables the utilization of living donor kidneys from healthy and willing donors incompatible with their intended recipients, the strategy poses complex challenges that have limited its adoption in United States and Canada. A consensus conference was convened March 29-30, 2012 to address the dynamic challenges and complexities of KPD that inhibit optimal implementation. Stakeholders considered donor evaluation and care, histocompatibility testing, allocation algorithms, financing, geographic challenges and implementation strategies with the goal to safely maximize KPD at every transplant center. Best practices, knowledge gaps and research goals were identified and summarized in this document.

Demographic, metabolic, and blood pressure characteristics of living kidney donors spanning five decades

While cautious criteria for selection of living kidney donors are credited for favorable outcomes, recent practice changes may include acceptance of less than ideal donors. To characterize trends in donor acceptance, the Renal and Lung Living Donors Evaluation (RELIVE) Study evaluated 8,951 kidney donors who donated between 1963 and 2007 at three major U.S. transplant centers. Over the study interval, there was an increase in the percentage of donors >40 years old from 38% to 51%; donors >60 years varied between 1% and 4%. The proportion of donors with obesity increased from 8% to 26% and with glucose intolerance from 9% to 25%. The percentage of hypertensive donors was consistent (5-8%). Accepted donors ≥60 years old were more likely to have obesity, glucose intolerance, and/or hypertension compared to younger donors (p<0.0001). Our results demonstrate important trends in acceptance of older and more obese donors. The fraction of older donors accepted with glucose intolerance or hypertension remains small and for the majority includes mild elevations in glucose or blood pressure that were previously classified as within normal limits.

Predictors of liver donation without kidney recovery in a cohort of expanded criteria donors: identifying opportunities to improve expanded criteria donor kidney utilization

To maximize deceased donation, it is necessary to facilitate organ recovery from expanded criteria donors (ECDs). Utilization of donors meeting the kidney definition for ECDs increases access to kidney transplantation and reduces waiting times; however, ECDs often do not proceed to kidney recovery. Based on a prospective study of three Organ Procurement Organizations in the United States, we describe the characteristics of donors meeting the Organ Procurement and Transplant Network (OPTN) ECD kidney definition (donor age 60+ or donor age 50-60 years with two of the following: final serum creatinine > 1.5 mg/dL, history of hypertension, or death from cerebral vascular accident) who donated a liver without kidney recovery. ECDs with organs recovered between February 2003 and September 2005 by New England Organ Bank, Gift of Life Michigan, and LifeChoice Donor Services were studied (n = 324). All donors were declared dead by neurological criteria. Data on a wide range of donor characteristics were collected, including donor demographics, medical history, cause of death, donor status during hospitalization, serological status, and donor kidney quality. Logistic regression models were used to identify donor characteristics predictive of liver-alone donation. Seventy-four of the 324 donors fulfilling the ECD definition for kidneys donated a liver alone (23%). History of diabetes, final serum creatinine > 1.5 mg/dL, age 70+, and presence of proteinuria were associated with liver-alone donation in univariate models. On multivariate analysis, only final serum creatinine > 1.5 mg/dL and age 70+ were independently predictive of liver donation alone. Older age and elevated serum creatinine may be perceived as stronger contraindications to kidney donation than the remaining elements of the ECD definition. It is likely that at least a proportion of these liver-alone donors represent missed opportunities for kidney transplantation.

Utilization of kidneys with similar kidney donor risk index values from standard versus expanded criteria donors

With the shortage of standard criteria donor (SCD) kidneys, efficient expanded criteria donor (ECD) kidney utilization has become more vital. We investigated the effects of the ECD label on kidney recovery, utilization and outcomes. Using data from the Scientific Registry of Transplant Recipients from November 2002 to May 2010, we determined recovery and transplant rates, and modeled discard risk, for kidneys within a range of kidney donor risk index (KDRI) 1.4-2.1 that included both SCD and ECD kidneys. To further compare similar quality kidneys, these kidneys were again divided into three KDRI intervals. Overall, ECD kidneys had higher recovery rates, but lower transplant rates. However, within each KDRI interval, SCD and ECD kidneys were transplanted at similar rates. Overall, there was increased risk for discard for biopsied kidneys. SCD kidneys in the lower two KDRI intervals had the highest risk of discard if biopsied. Pumped kidneys had a lower risk of discard, which was modulated by KDRI for SCD kidneys but not ECD kidneys. Although overall ECD graft survival was worse than SCD, there were no differences within individual KDRI intervals. Thus, ECD designation adversely affects neither utilization nor outcomes beyond that predicted by KDRI.

Call to develop a standard acquisition charge model for kidney paired donation

We propose a Medicare Demonstration Project to develop a standard acquisition charge for kidney paired donation. A new payment strategy is required because Medicare and commercial insurance companies may not directly pay living donor costs intended to lead to transplantation of a beneficiary of a different insurance provider. Until the 1970s, when organ procurement organizations were empowered to serve as financial intermediaries to pay the upfront recovery expenses for deceased donor kidneys before knowing the identity of the recipient, there existed similar limitations in the recovery and placement of deceased donor organs. Analogous to the recovery of deceased donor kidneys, kidney paired donation requires the evaluation of living donors before identifying their recipient. Tissue typing, crossmatching and transportation of living donors or their kidneys represent additional financial barriers. Finally, the administrative expenses of the organizations that identify and coordinate kidney paired donation transplantation require reimbursement akin to that necessary for organ procurement organizations. To expand access to kidney paired donation for more patients, we propose a model to reimburse paired donation expenses analogous to the proven strategy used for over 30 years to pay for deceased donor solid organ transplantation in America.

Transplanting kidneys without points for HLA-B matching: consequences of the policy change

In 2003, the US kidney allocation system was changed to eliminate priority for HLA-B similarity. We report outcomes from before and after this change using data from the Scientific Registry of Transplant Recipients (SRTR). Analyses were based on 108 701 solitary deceased donor kidney recipients during the 6 years before and after the policy change. Racial/ethnic distributions of recipients in the two periods were compared (chi-square); graft failures were analyzed using Cox models. In the 6 years before and after the policy change, the overall number of deceased donor transplants rose 23%, with a larger increase for minorities (40%) and a smaller increase for non-Hispanic whites (whites) (8%). The increase in the proportion of transplants for non-whites versus whites was highly significant (p < 0.0001). Two-year graft survival improved for all racial/ethnic groups after implementation of this new policy. Findings confirmed prior SRTR predictions. Following elimination of allocation priority for HLA-B similarity, the deficit in transplantation rates among minorities compared with that for whites was reduced but not eliminated; furthermore, there was no adverse effect on graft survival.

Predictability of survival models for waiting list and transplant patients: calculating LYFT

'Life years from transplant' (LYFT) is the extra years of life that a candidate can expect to achieve with a kidney transplant as compared to never receiving a kidney transplant at all. The LYFT component survival models (patient lifetimes with and without transplant, and graft lifetime) are comparable to or better predictors of long-term survival than are other predictive equations currently in use for organ allocation. Furthermore, these models are progressively more successful at predicting which of two patients will live longer as their medical characteristics (and thus predicted lifetimes) diverge. The C-statistics and the correlations for the three LYFT component equations have been validated using independent, nonoverlapping split-half random samples. Allocation policies based on these survival models could lead to substantial increases in the number of life years gained from the current donor pool.

Kidney and pancreas transplantation in the United States, 1998-2007: access for patients with diabetes and end-stage renal disease

Although the number of candidates on the kidney transplant waiting list at year-end rose from 40 825 to 76 070 (86%) between 1998 and 2007, recent growth principally reflects increases in the number of patients in inactive status. The number of active patients increased by 'only' 4510 between 2002 and 2007, from 44 263 to 48 773. There were 6037 living donor and 10 082 deceased donor kidney transplants in 2007. Patient and allograft survival was best for recipients of living donor kidneys, least for expanded criteria donor (ECD) deceased donor kidneys, and intermediate for non-ECD deceased donor kidneys. The total number of pancreas transplants peaked at 1484 in 2004 and has since declined to 1331. Among pancreas recipients, those with simultaneous pancreas-kidney (SPK) transplants experienced the best pancreas graft survival rates: 86% at 1 year and 53% at 10 years. Between 1998 and 2006, among diabetic patients with end-stage renal disease (ESRD) who were under the age of 50 years, 23% of all and 62% of those waitlisted received a kidney-alone or SPK transplant. In contrast, 6% of diabetic patients aged 50-75 years with ESRD were transplanted, representing 46% of those waitlisted from this cohort. Access to kidney-alone or SPK transplantation varies widely by state.

Should pediatric patients wait for HLA-DR-matched renal transplants?

Graft survival rates from deceased donors aged 35 years or less among all primary pediatric kidney transplant recipients in the United States between 1996 and 2004 were retrospectively examined to determine the effect of HLA-DR mismatches on graft survival. Zero HLA-DR-mismatched kidneys had statistically comparable 5-year graft survival (71%), to 1-DR-mismatched kidneys (69%) and 2-DR-mismatched kidneys (71%). When compared to donors less than 35 years of age, the relative rate of allograft failure was 1.32 (p = 0.0326) for donor age greater than or equal to age 35. There was no statistical increase in the odds of developing a panel-reactive antibody (PRA) greater than 30% at the time of second waitlisting, based upon the degree of HLA-A, -B or -DR mismatch of the first transplant, nor was there a 'dose effect' when more HLA antigens were mismatched between the donor and recipient. Therefore, pediatric transplant programs should utilize the recently implemented Organ Procurement and Transplantation Network's (OPTN)allocation policy, which prioritizes pediatric recipients to receive kidneys from deceased donors less than 35 years of age, and should not turn down such kidney offers to wait for a better HLA-DR-matched kidney.

Calculating life years from transplant (LYFT): methods for kidney and kidney-pancreas candidates

The Organ Procurement and Transplantation Network (OPTN) Kidney Committee is considering a proposal for a new deceased donor kidney allocation system. Among the components under consideration is a strategy to rank candidates in part by the estimated incremental years of life that are expected to be achieved with a transplant from a specific available deceased donor, computed as the difference in expected median lifespan with that transplant compared with remaining on dialysis. This concept has been termed life years from transplant or LYFT. Median lifespans could be calculated, based on objective medical criteria, for each candidate when a deceased donor kidney becomes available, based on Cox regression models using current candidate and donor medical information. The distribution of the calculated LYFT scores for an average nonexpanded criteria donor kidney is similar across candidate sex, race/ethnicity, insurance status and, with the exception of diabetes, diagnosis. LYFT scores tend to be higher for younger candidates and lower for diabetics receiving a kidney-alone rather than a simultaneous kidney-pancreas transplant. Prioritizing candidates with higher LYFT scores for each available kidney could substantially increase total years of life among both transplant candidates and recipients. LYFT is also a powerful metric for assessing trends in allocation outcomes and for comparing alternative allocation systems.

Determinants of discard of expanded criteria donor kidneys: impact of biopsy and machine perfusion

We examined factors associated with expanded criteria donor (ECD) kidney discard. Scientific Registry of Transplant Recipients (SRTR)/Organ Procurement and Transplantation Network (OPTN) data were examined for donor factors using logistic regression to determine the adjusted odds ratio (AOR) of discard of kidneys recovered between October 1999 and June 2005. Logistic and Cox regression models were used to determine associations with delayed graft function (DGF) and graft failure. Of the 12,536 recovered ECD kidneys, 5139 (41%) were discarded. Both the performance of a biopsy (AOR = 1.21, p = 0.02) and the degree of glomerulosclerosis (GS) on biopsy were significantly associated with increased odds of discard. GS was not consistently associated with DGF or graft failure. The discard rate of pumped ECD kidneys was 29.7% versus 43.6% for unpumped (AOR = 0.52, p < 0.0001). Among pumped kidneys, those with resistances of 0.26-0.38 and >0.38 mmHg/mL/min were discarded more than those with resistances of 0.18-0.25 mmHg/mL/min (AOR = 2.5 and 7.9, respectively). Among ECD kidneys, pumped kidneys were less likely to have DGF (AOR = 0.59, p < 0.0001) but not graft failure (RR = 0.9, p = 0.27). Biopsy findings and machine perfusion are important correlates of ECD kidney discard; corresponding associations with graft failure require further study.

Kidney and pancreas transplantation in the United States, 1997-2006: the HRSA Breakthrough Collaboratives and the 58 DSA Challenge

Growth in the number of active patients on the kidney transplant waiting list has slowed. Projections based on the most recent 5-year data suggest the total waiting list will grow at a rate of 4138 registrations per year, whereas the active waiting list will increase at less than one-sixth that rate, or 663 registrations per year. The last 5 years have seen a small trend toward improved unadjusted allograft survival for living and deceased donor kidneys. Since 2004 the overall number of pancreas transplants has declined. Among pancreas recipients, those with simultaneous kidney-pancreas transplants experienced the highest pancreas graft survival rates. In response to the ongoing shortage of deceased donor organs, the US Health Resources and Services Administration launched the Organ Donation Breakthrough Collaborative in September 2003 and the Organ Transplantation Breakthrough Collaborative (OTBC) in October 2005. The 58 DSA Challenge is prominent among the goals adopted by the OTBC. Its premise: were each of the 58 existing donation service areas to increase the number of kidney transplants performed within their boundaries by 10 per month, an additional 7000 transplants over current annual levels would result. Such an increase could potentially eliminate the national kidney transplantation waiting list by 2030.

Kidney transplantation as primary therapy for end-stage renal disease: a National Kidney Foundation/Kidney Disease Outcomes Quality Initiative (NKF/KDOQITM) conference

BACKGROUND AND OBJECTIVES

Kidney transplantation is the most desired and cost-effective modality of renal replacement therapy for patients with irreversible chronic kidney failure (end-stage renal disease, stage 5 chronic kidney disease). Despite emerging evidence that the best outcomes accrue to patients who receive a transplant early in the course of renal replacement therapy, only 2.5% of incident patients with end-stage renal disease undergo transplantation as their initial modality of treatment, a figure largely unchanged for at least a decade.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The National Kidney Foundation convened a Kidney Disease Outcomes Quality Initiative (KDOQI) conference in Washington, DC, March 19 through 20, 2007, to examine the issue. Fifty-two participants representing transplant centers, dialysis providers, and payers were divided into three work groups to address the impact of early transplantation on the chronic kidney disease paradigm, educational needs of patients and professionals, and finances of renal replacement therapy.

RESULTS

Participants explored the benefits of early transplantation on costs and outcomes, identified current barriers (at multiple levels) that impede access to early transplantation, and recommended specific interventions to overcome those barriers.

CONCLUSIONS

With implementation of early education, referral to a transplant center coincident with creation of vascular access, timely transplant evaluation, and identification of potential living donors, early transplantation can be an option for substantially more patients with chronic kidney disease.

Insurance type and minority status associated with large disparities in prelisting dialysis among candidates for kidney transplantation

BACKGROUND AND OBJECTIVES

Disparities in time to placement on the waiting list on the basis of socioeconomic factors decrease access to deceased-donor renal transplantation for some groups of patients with end-stage renal disease. This study was undertaken to determine candidate factors that influence duration of dialysis before placement on the waiting list among candidates for deceased-donor renal transplantation in the United States from January 2001 to December 2004 and the impact of Medicare eligibility rules on access.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Access to the waiting list was measured as the percentage of all wait-listed candidates in the Scientific Registry of Transplant Recipients database who were listed before dialysis and by the duration of dialysis before placement on the waiting list. Multivariate logistic and linear regressions were used to determine variables that were predictive of preemptive listing and the duration of dialysis before listing.

RESULTS

The odds for preemptive placement on the waiting list improved during the course of the study period, whereas the median duration of prelisting dialysis did not. The candidate factors that were associated with low rates of preemptive listing and prolonged exposure to prelisting dialysis included Medicare insurance, minority race/ethnicity, and low educational attainment. In patients who were listed after the age of 64 yr, the adverse effect of Medicare insurance on access largely disappeared.

CONCLUSIONS

The disparity in dialysis exposure could potentially be diminished by concerted efforts on the part of the nephrology and transplant communities to promote early referral and preemptive placement on the waiting list, by calculating waiting time from the date of initiation of dialysis for patients who are on dialysis at the time of referral, and by relaxing Medicare eligibility requirements.

The rationale for the new deceased donor pancreas allocation schema

BACKGROUND

To ensure the continued success of whole organ pancreas and islet transplantation, deceased donor pancreas allocation policy must continue to evolve.

METHODS

To assess the existing system, the Organ Procurement and Transplantation Network (OPTN)/United Network for Organ Sharing Kidney and Pancreas Transplant Committee retrospectively analyzed the disposition and outcomes of deceased donor pancreata in the United States between January 1, 2000 and December 31, 2003.

RESULTS

During the time period studied, consent was obtained but the pancreas was not recovered in 48% (11,820) of organ donors. The most common reasons given for nonrecovery were poor quality of the pancreas and difficulty in placement. Of whole organ pancreata that were transplanted, 90% were from donors with a body mass index (BMI) <or=30 kg/m and age <or=50 years. Pancreata from older and more obese donors were used more often for islet transplantation or research. For simultaneous pancreas-kidney transplants, the 1- and 3-year pancreas graft survival was lower when the donor was age >50 years (P=0.04), and there were trends toward lower graft survival with donor BMI >30 (P=0.06) and increasing cold-ischemia time.

CONCLUSIONS

Based on these data, the OPTN adopted a new allocation algorithm in which pancreata from donors >30 kg/m or >50 years of age are, unless accepted for a local whole organ pancreas transplant candidate, preferentially allocated for islet transplantation. These data also suggest that many good quality pancreata are not procured, emphasizing the need for improved communication and cooperation between organ procurement organizations and pancreas and islet transplant programs.

Developing organ offer and acceptance measures: when 'good' organs are turned down

Turndowns of offers of deceased donor kidneys for transplantation can contribute to inefficiencies in the organ distribution system and inequality in access to donated organs. Match run data were obtained for 4967 'good' kidneys placed and transplanted in 2005 after fewer than 50 offers. These kidneys were not recovered from donation after cardiac death or expanded criteria donors, or from donors with a history of substance abuse. On average, these good kidneys were not accepted until after seven offers to candidates and after offers to 2.4 programs. Models for the likelihood of acceptance found several donor and candidate characteristics to be significantly related to acceptance rates (p < 0.05). After accounting for these variables, there remained 2- to 3-fold differences among transplant programs in acceptance rates. These models could be used to identify kidney transplant centers with exceptional acceptance practices. Several strategies might be employed to increase acceptance rates for good organs.

Geographic variability in access to primary kidney transplantation in the United States, 1996-2005

This article focuses on geographic variability in patient access to kidney transplantation in the United States. It examines geographic differences and trends in access rates to kidney transplantation, in the component rates of wait-listing, and of living and deceased donor transplantation. Using data from Centers for Medicare and Medicaid Services and the Organ Procurement and Transplantation Network/Scientific Registry of Transplant Recipients, we studied 700,000+ patients under 75, who began chronic dialysis treatment, received their first living donor kidney transplant, or were placed on the waiting list pre-emptively. Relative rates of wait-listing and transplantation by State were calculated using Cox regression models, adjusted for patient demographics. There were geographic differences in access to the kidney waiting list and to a kidney transplant. Adjusted wait-list rates ranged from 37% lower to 64% higher than the national average. The living donor rate ranged from 57% lower to 166% higher, while the deceased donor transplant rate ranged from 60% lower to 150% higher than the national average. In general, States with higher wait-listing rates tended to have lower transplantation rates and States with lower wait-listing rates had higher transplant rates. Six States demonstrated both high wait-listing and deceased donor transplantation rates while six others, plus D.C. and Puerto Rico, were below the national average for both parameters.

Repeat organ transplantation in the United States, 1996-2005

The prospect of graft loss is a problem faced by all transplant recipients, and retransplantation is often an option when loss occurs. To assess current trends in retransplantation, we analyzed data for retransplant candidates and recipients over the last 10 years, as well as current outcomes. During 2005, retransplant candidates represented 13.5%, 7.9%, 4.1% and 5.5% of all newly registered kidney, liver, heart and lung candidates, respectively. At the end of 2005, candidates for retransplantation accounted for 15.3% of kidney transplant candidates, and lower proportions of liver (5.1%), heart (5.3%) and lung (3.3%) candidates. Retransplants represented 12.4% of kidney, 9.0% of liver, 4.7% of heart and 5.3% of lung transplants performed in 2005. The absolute number of retransplants has grown most notably in kidney transplantation, increasing 40% over the last 10 years; the relative growth of retransplantation was most marked in heart and lung transplantation, increasing 66% and 217%, respectively. The growth of liver retransplantation was only 11%. Unadjusted graft survival remains significantly lower after retransplantation in the most recent cohorts analyzed. Even with careful case mix adjustments, the risk of graft failure following retransplantation is significantly higher than that observed for primary transplants.

Immunosuppression: evolution in practice and trends, 1994-2004

Over the last 10 years, there have been important changes in immunosuppression management and strategies for solid-organ transplantation, characterized by the use of new immunosuppressive agents and regimens. An organ-by-organ review of OPTN/SRTR data showed several important trends in immunosuppression practice. There is an increasing trend toward the use of induction therapy with antibodies, which was used for most kidney, pancreas after kidney (PAK), simultaneous pancreas-kidney (SPK) and pancreas transplant alone (PTA) recipients in 2004 (72-81%) and for approximately half of all intestine, heart and lung recipients. The highest usage of the tacrolimus/mycophenolate mofetil combination as discharge regimen was reported for SPK (72%) and PAK (64%) recipients. Maintenance of the original discharge regimen through the first 3 years following transplantation varied significantly by organ and drug. The usage of calcineurin inhibitors for maintenance therapy was characterized by a clear transition from cyclosporine to tacrolimus. Corticosteroids were administered to the majority of patients; however, steroid-avoidance and steroid-withdrawal protocols have become increasingly common. The percentage of patients treated for acute rejection during the first year following transplantation has continued to decline, reaching 13% for those who received a kidney in 2003, 48% of which cases were treated with antibodies.

Report of a National Conference on Donation after cardiac death

A national conference on organ donation after cardiac death (DCD) was convened to expand the practice of DCD in the continuum of quality end-of-life care. This national conference affirmed the ethical propriety of DCD as not violating the dead donor rule. Further, by new developments not previously reported, the conference resolved controversy regarding the period of circulatory cessation that determines death and allows administration of pre-recovery pharmacologic agents, it established conditions of DCD eligibility, it presented current data regarding the successful transplantation of organs from DCD, it proposed a new framework of data reporting regarding ischemic events, it made specific recommendations to agencies and organizations to remove barriers to DCD, it brought guidance regarding organ allocation and the process of informed consent and it set an action plan to address media issues. When a consensual decision is made to withdraw life support by the attending physician and patient or by the attending physician and a family member or surrogate (particularly in an intensive care unit), a routine opportunity for DCD should be available to honor the deceased donor's wishes in every donor service area (DSA) of the United States.

Mortality after kidney transplantation: a comparison between the United States and Canada

There is a paucity of comparative studies on country-specific outcomes in kidney transplantation. We compared post-transplant mortality among primary, adult, solitary kidney transplant recipients (KTR) from the United States (n = 70 708) and Canada (n = 5773), between January 1, 1991 and December 31, 1998, using data from the Scientific Registry of Transplant Recipients and the Canadian Organ Replacement Register. Multivariable Cox regression revealed higher adjusted post-transplant mortality among U.S. (vs. Canadian) KTR (HR = 1.35 [95% CI 1.24, 1.47; p < 0.005]). Mortality risk in the first post-transplant year was similar in both countries but higher in the United States beyond the first year (HR = 1.49-1.53; p < 0.005). There was no difference in mortality among patients transplanted within 1 year of starting dialysis, but mortality was increased in U.S. (vs. Canadian) patients after 1-2 and 4+ years on dialysis (HR = 1.36-1.66; p < 0.005). Greater mortality was also seen in U.S. patients with diabetes mellitus and/or graft failure. In conclusion, there are considerable differences in the survival of KTR in the United States and Canada. A detailed examination of factors contributing to this variation may yield important insights into improving outcomes for all KTR.

Impact of the Expanded Criteria Donor Allocation System on the Use of Expanded Criteria Donor Kidneys

BACKGROUND

The U.S. Organ Procurement and Transplantation Network recently implemented a policy allocating expanded criteria donor (ECD) kidneys by waiting time alone. ECD kidneys were defined as having a risk of graft failure > or = 1.7 times that of ideal donors. ECDs include any donor > or = 60 years old and donors 50 to 59 years old with at least two of the following: terminal creatinine >1.5 mg/dL, history of hypertension, or death by cerebrovascular accident. The impact of this policy on use of ECD kidneys is assessed.

METHODS

The authors compared use of ECD kidneys recovered in the 18 months immediately before and after policy implementation. Differences were tested using t test and chi2 analyses.

RESULTS

There was an 18.3% increase in ECD kidney recoveries and a 15.0% increase in ECD kidney transplants in the first 18 months after policy implementation. ECD kidneys made up 22.1% of all recovered kidneys and 16.8% of all transplants, compared with 18.8% (P<0.001) and 14.5% (P<0.001), respectively, in the prior period. The discard rate was unchanged. The median relative risk (RR) for graft failure for transplanted ECD kidneys was 2.07 versus 1.99 in the prepolicy period (P=not significant); the median RR for procured ECD kidneys was unchanged at 2.16. The percentage of transplanted ECD kidneys with cold ischemia times (CIT) <12 hr increased significantly; the corresponding percentage for CIT > or = 24 hr decreased significantly.

CONCLUSIONS

The recent increase in ECD kidney recoveries and transplants appears to be related to implementation of the ECD allocation system.

Immunosuppression: evolution in practice and trends, 1993-2003

Immunosuppression trends for solid organ transplantation have undergone a perceptible shift over the past decade. This period is of interest because it was during this time that the Food and Drug Administration (FDA) expanded the variety of medications to allow for alternatives in immunosuppressive management. An organ-by-organ review of SRTR data identifies several important trends. Antibody induction continues to be used for the majority of kidney (70%), simultaneous pancreas-kidney (SPK, 79%) pancreas after kidney (PAK, 74%), and intestine recipients (74%). It is used for under half of thoracic organ recipients and remains uncommon for liver transplant recipients (20%). The type of antibody preparation utilized has shifted from muromonab-CD3 and horse ATG to rabbit ATG and monoclonal anti-IL-2 receptor antagonists. Calcineurin inhibitors continue to be used for maintenance immunosuppression for most recipients, although there has been a shift from cyclosporine to tacrolimus. A clear transition is apparent in the choice of antimetabolite from azathioprine to mycophenolate mofetil. Although corticosteroids continue to be used as maintenance immunosuppression for most recipients prior to discharge, there is evidence that efforts of steroid avoidance protocols are having an impact across all organs, as slight decreases in their use have been observed.

Transplantation in the diabetic patient with advanced chronic kidney disease: a task force report

On May 7 to 8, 2003, more than 60 physicians, surgeons, nurses, and allied health professionals met in Chicago, IL, to discuss state-of-the-art approaches to transplantation in the clinical management of patients with diabetes and advanced chronic kidney disease. Four work groups addressed pretransplantation evaluation and management, therapeutic alternatives for treatment of patients with chronic kidney disease, posttransplantation diabetes mellitus, and improving long-term kidney transplant outcomes in patients with diabetes. This report summarizes the deliberations and recommendations of the task force.

Development and current status of ECD kidney transplantation

The worsening shortage of donor kidneys for transplant and the aging of both the donor and candidate populations have contributed to the increasing importance of ECD kidney transplantation. While ECD transplants have an increased risk of graft failure, for most candidates patient survival is still improved over remaining on dialysis. Because of this risk, however, ECD kidneys have a high likelihood of discard; significant geographic variation in discard and transplant rates impedes maximum utilization of these kidneys. The ECD allocation system was implemented to help facilitate expeditious placement of ECD kidneys to pre-consented candidates by a simplified allocation algorithm. Under this system, recovery and transplantation of ECD kidneys have increased at rates not seen with non-ECD kidneys and not predicted by preexisting trends. More disappointing has been the lack of effect on the percentage of discards and DGF, despite significant reductions in CIT. The disadvantage in graft survival for ECD kidneys extends equally across the spectrum of recipient characteristics, such that no one group of candidates has a proportionately smaller increase in risk. However, benefit analyses comparing the risk of accepting an ECD kidney versus waiting for a non-ECD kidney demonstrate a significant ECD benefit for older and diabetic candidates in regions with prolonged waiting times. The potential value of an ECD kidney to an individual candidate hinges upon the ability to receive it substantially earlier than a non-ECD kidney. Thus, future allocation efforts may focus on ensuring that is the case. In allocation driven by net benefit, ECD kidneys may become an alternative for those who might not otherwise receive a kidney transplant.

Transplantation in the diabetic patient with advanced chronic kidney disease: a task force report

On May 7 to 8, 2003, more than 60 physicians, surgeons, nurses, and allied health professionals met in Chicago, IL, to discuss state-of-the-art approaches to transplantation in the clinical management of patients with diabetes and advanced chronic kidney disease. Four work groups addressed pretransplantation evaluation and management, therapeutic alternatives for treatment of patients with chronic kidney disease, posttransplantation diabetes mellitus, and improving long-term kidney transplant outcomes in patients with diabetes. This report summarizes the deliberations and recommendations of the task force.

Association of center volume with outcome after liver and kidney transplantation

Outcomes for certain surgical procedures have been linked with volume: hospitals performing a high number of procedures demonstrate better outcomes than do low-volume centers. This study examines the effect of volume on hepatic and renal transplant outcomes. Data from the Scientific Registry of Transplant Recipients were analyzed for transplants performed from 1996-2000. Transplant centers were assigned to volume quartiles (kidney) or terciles (liver). Logistic regression models, adjusted for clinical characteristics and transplant center clustering, demonstrate the effect of transplant center volume quantile on 1-year post-transplant patient mortality (liver) and graft loss (kidney). The unadjusted rate of renal graft loss within 1 year was significantly lower at high volume centers (8.6%) compared with very low (9.6%), low (9.9%) and medium (9.7%) volume centers (p = 0.0014). After adjustment, kidney transplant at very low [adjusted odds ratio (AOR) 1.22; p = 0.043) and low volume (AOR 1.22 p = 0.041) centers was associated with a higher incidence of graft loss when compared with high volume centers. Unadjusted 1-year mortality rates for liver transplant were significantly different at high (15.9%) vs. low (16.9%) or medium (14.7%) volume centers. After adjustment, low volume centers were associated with a significantly higher risk of death (AOR 1.30; p = 0.0036). There is considerable variability in the range of failure between quantiles after kidney and liver transplant. Transplant outcomes are better at high volume centers; however, there is no clear minimal threshold volume.

Kidney and pancreas transplantation

Data from the Scientific Registry of Transplant Recipients offer a unique and comprehensive view of US trends in kidney and pancreas waiting list characteristics and outcomes, transplant recipient and donor characteristics, and patient and allograft survival. Important findings from our review of developments during 2002 and the decade's transplantation trends appear below. The kidney waiting list has continued to grow, increasing from 47,830 in 2001 to 50,855 in 2002. This growth has occurred despite the increasing importance of living donor transplantation, which rose from 28% of total kidney transplants in 1993 to 43% in 2002. Policies and procedures to expedite the allocation of expanded criteria donor (ECD) kidneys were developed and implemented during 2002, when 15% of deceased donor transplants were performed with ECD kidneys. Unadjusted 1- and 5-year deceased donor kidney allograft survivals were 81% and 51% for ECD kidney recipients, and 90% and 68% for non-ECD kidney recipients, respectively. Although more patients have been placed on the simultaneous kidney-pancreas waiting list, the number of these transplants dropped from a peak of 970 in 1998 to 905 in 2002. This decline may be due to competition for organs from increasing numbers of isolated pancreas and islet transplants.

Immunosuppression and the risk of post-transplant malignancy among cadaveric first kidney transplant recipients

The success of renal transplantation may be counterbalanced by serious adverse medical events. The effect of immunosuppression on the incidence of de novo neoplasms among kidney recipients should be monitored continuously. Using data from the Scientific Registry of Transplant Recipients, we studied the association of induction therapy by immunosuppression with antilymphocyte antibodies, with the development of de novo neoplasms. The study population included more than 41 000 recipients who received a cadaveric first kidney transplant after December 31, 1995, and were followed through February 28, 2002. Using Cox regression models, we estimated time to development of two types of malignancy: de novo solid tumors and post-transplant lymphoproliferative disorder (PTLD). We made adjustments for several patient demographic factors and comorbidities. Induction therapy was significantly associated with a higher relative risk (RR) of PTLD (RR = 1.78, p < 0.001), but not with a greater likelihood of de novo tumors (RR = 1.07, p = 0.42). Treatment with maintenance tacrolimus vs. cyclosporine showed a significantly different RR of developing de novo tumors for recipients with induction than for those not receiving induction (p = 0.024). These new estimates of the magnitude of malignancy risk associated with induction therapy may be useful for clinical practice.

Pharmacodynamics, pharmacokinetics, and safety of multiple doses of FTY720 in stable renal transplant patients: a multicenter, randomized, placebo-controlled, phase I study

BACKGROUND

FTY720, a novel immunomodulator, displays potent immunosuppressive activity in a variety of preclinical transplant models. This study examined the safety, pharmacodynamics, and pharmacokinetics of multiple doses of FTY720 in stable renal transplant patients.

METHODS

This randomized, multicenter, double-blind, placebo-controlled, phase I study included adults who had been maintained on a regimen of cyclosporine A (CsA) microemulsion and prednisone (or its equivalent) for at least 1 year after renal transplantation. Patients received once-daily doses of 0.125, 0.25, 0.5, 1.0, 2.5, or 5.0 mg FTY720, or placebo for 28 days. After completion of study drug administration, the patients were monitored until day 56 by serial laboratory tests, clinical examinations, and recording of adverse events. The study includes 76 treatment courses (61 FTY720 and 15 placebo), with 65 patients enrolled once and 11 reenrolled.

RESULTS

FTY720 doses greater than or equal to 1.0 mg/day produced a significant reduction in peripheral blood lymphocyte count by up to 85%, which reversed within 3 days after discontinuation of study medication. Compared with placebo-treated patients, FTY720 subjects did not show a major increase in adverse events or a change in renal function. Pharmacokinetic measurements revealed that FTY720 displayed linear relations of doses and concentrations over a wide range, but had no effect on CsA exposure.

CONCLUSIONS

At doses up to 5.0 mg/day for 28 days, stable renal transplant patients treated with FTY720 in combination with CsA and prednisone displayed a dose-dependent, reversible decline in peripheral blood lymphocytes without an enhanced incidence of collateral toxicities, except possibly bradycardia.