High-Functioning Deceased Donor Kidney Transplant System Characteristics: The British Columbia Experience With an Opt-In System

Rationale & Objective

A high level of cooperation between organ procurement organizations and transplant programs may help maximize use of deceased donor kidneys. The practices that are essential for a high functioning organ donation and transplant system remain uncertain. We sought to report metrics of organ donation and transplant performance in British Columbia, Canada, and to assess the association of specific policies and practices that contribute to the system's performance.

Study Design

A retrospective observational study.

Setting & Participants

Referred deceased organ donors in British Columbia were used in the study from January 1, 2016, to December 31 2019.

Exposures

Provincial, organ procurement organization, and center level policies were implemented to improve donor referral and organ utilization.

Outcomes

Assessment of donor and kidney utilization along steps of the critical pathway for organ donation.

Analytical Approach

Deceased donors were classified according to the critical pathway for organ donation and key donation and transplant metrics were identified.

Results

There were 1,948 possible donors referred. Of 1,948, 754 (39%) were potential donors. Of 754 potential donors, 587 (78%) were consented donors. Of 587 consented donors, 480 (82%) were eligible kidney donors. Of 480 eligible kidney donors, 438 (91%) were actual kidney donors. And of 438 actual kidney donors, 432 (99%) were utilized kidney donors. One-year all-cause allograft survival was 95%. Practices implemented to improve the system's performance included hospital donor coordinators, early communication between the organ procurement organization and transplant nephrologists, dedicated organ recovery and implant surgeons, aged-based kidney allocation, and hospital admission of recipients before kidney recovery.

Limitations

Assignment of causality between individual policies and practices and organ donation and utilization is limited in this observational study.

Conclusions

In British Columbia, consent for donation, utilization of donated kidneys, and transplant survival are exceptionally high, suggesting the importance of an integrated deceased donor and kidney transplant service.

Enhancing Kidney Transplantation and the Role of Xenografts: Report of a Scientific Workshop Sponsored by the National Kidney Foundation

Chronic kidney disease affects an estimated 37 million people in the United States; of these,>800,000 have end-stage renal disease requiring chronic dialysis or a kidney transplant to survive. Despite efforts to increase the donor kidney supply, approximately 100,000 people are registered on the kidney transplant wait-list with no measurable decrease over the past 2 decades. The outcomes of kidney transplantation are significantly better than for chronic dialysis: kidney transplant recipients have lower rates of mortality and cardiovascular events and better quality of life, but wait-list time matters. Time on dialysis waiting for a deceased-donor kidney is a strong independent risk factor for outcomes after a kidney transplant. Deceased-donor recipients with wait-list times on dialysis of<6 months have graft survival rates equivalent to living-donor recipients with waitlist times on dialysis of>2 years. In 2021,>12,000 people had been on the kidney transplant waitlist for ≥5 years. As the gap between the demand for and availability of donor kidneys for allotransplantation continues to widen, alternative strategies are needed to provide a stable, sufficient, and timely supply. A strategy that is gaining momentum toward clinical application is pig-to-human kidney xenotransplantation. This report summarizes the proceedings of a meeting convened on April 11-12, 2022, by the National Kidney Foundation to review and assess the state of pig-to-human kidney xenotransplantation as a potential cure for end-stage renal disease.

Pretransplant screening for coronary artery disease: data are required before practice change

Declining rates of peritransplant cardiovascular death, an increasing burden of pretransplant tests, and concerns about the effectiveness of screening candidates for coronary artery disease have led many transplant programs to de-escalate screening protocols. Recent Kidney Disease: Improving Global Outcomes and American Heart Association scientific statements and guidelines neatly summarize current evidence, but also identify areas of need. Here, we argue that key questions should be addressed by adequately powered clinical trials before our long-held screening paradigms are completely rewritten.

A Machine Learning-Driven Virtual Biopsy System For Kidney Transplant Patients

In kidney transplantation, day-zero biopsies are used to assess organ quality and discriminate between donor-inherited lesions and those acquired post-transplantation. However, many centers do not perform such biopsies since they are invasive, costly and may delay the transplant procedure. We aim to generate a non-invasive virtual biopsy system using routinely collected donor parameters. Using 14,032 day-zero kidney biopsies from 17 international centers, we develop a virtual biopsy system. 11 basic donor parameters are used to predict four Banff kidney lesions: arteriosclerosis, arteriolar hyalinosis, interstitial fibrosis and tubular atrophy, and the percentage of renal sclerotic glomeruli. Six machine learning models are aggregated into an ensemble model. The virtual biopsy system shows good performance in the internal and external validation sets. We confirm the generalizability of the system in various scenarios. This system could assist physicians in assessing organ quality, optimizing allograft allocation together with discriminating between donor derived and acquired lesions post-transplantation.

Frailty and Clinical Outcomes in Patients Treated With Hemodialysis: A Prospective Cohort Study

Rationale and Objective

Frailty is common among people with kidney failure treated with hemodialysis (HD). The objective was to describe how frailty evolves over time in people treated by HD, how improvements in frailty and frailty markers are associate with clinical outcomes, and the characteristics that are associated with improvement in frailty.

Study Design

Prospective cohort study.

Setting and Participants

Adults initiating thrice weekly in-center HD in Canada.

Exposure

We classified frailty using a 5-point score (3 or more indicates frailty) based on physical inactivity, slowness or weakness, poor endurance or exhaustion, and malnutrition. We categorized the frailty trajectory as never present, improving, deteriorating, and always present.

Outcomes

All-cause death, hospitalizations, and placement into long-term care.

Analytical Approach

We examined the association between time-varying frailty measures and these outcomes using Cox and negative binomial models, after adjustment for potential confounders.

Results

985 participants were included and followed up for a median of 33 months; 507 (51%) died, 761 (77%) experienced ≥1 hospitalization and 115 (12%) entered long-term care. Overall, 760 (77%) reported frailty during follow-up. Three-quarters (78%) of those with frailty at baseline remained frail throughout the follow-up, 46% without baseline frailty became frail, and 23% with baseline frailty became nonfrail. Higher frailty scores were associated with an increased risk of mortality (fully adjusted HR, 1.58 per unit; 95% CI, 1.39-1.80) and an increased rate of hospitalization (RR, 1.16 per unit; 95% CI, 1.09-1.23). Compared with those who were frail throughout the follow-up, participants with frailty at baseline but improving during follow-up showed a lower mortality (HR, 0.59; 95% CI, 0.42-0.81), and a lower rate of hospitalization (RR, 0.70; 95% CI, 0.56-0.87).

Limitations

There was missing data on frailty at baseline and during follow-up.

Conclusions

Frailty was associated with a higher risk of poor outcomes compared with those without frailty, and participants whose status improved from frail to nonfrail showed better clinical outcomes than those who remained frail. These findings emphasize the importance of identifying and implementing effective treatments for frailty in patients receiving maintenance HD.

The Benefits of Preemptive Transplantation Using High-Kidney Donor Profile Index Kidneys

BACKGROUND

The Kidney Donor Profile Index (KDPI) is a percentile score summarizing the likelihood of allograft failure: A KDPI ≥85% is associated with shorter allograft survival, and 50% of these donated kidneys are not currently used for transplantation. Preemptive transplantation (transplantation without prior maintenance dialysis) is associated with longer allograft survival than transplantation after dialysis; however, it is unknown whether this benefit extends to high-KDPI transplants. The objective of this analysis was to determine whether the benefit of preemptive transplantation extends to recipients of transplants with a KDPI ≥85%.

METHODS

This retrospective cohort study compared the post-transplant outcomes of preemptive and nonpreemptive deceased donor kidney transplants using data from the Scientific Registry of Transplant Recipients. 120,091 patients who received their first, kidney-only transplant between January 1, 2005, and December 31, 2017, were studied, including 23,211 with KDPI ≥85%. Of this cohort, 12,331 patients received a transplant preemptively. Time-to-event models for the outcomes of allograft loss from any cause, death-censored graft loss, and death with a functioning transplant were performed.

RESULTS

Compared with recipients of nonpreemptive transplants with a KDPI of 0%-20% as the reference group, the risk of allograft loss from any cause in recipients of a preemptive transplant with KDPI ≥85% (hazard ratio [HR], 1.51; 95% confidence interval [CI], 1.39 to 1.64) was lower than that in recipients of nonpreemptive transplant with a KDPI ≥85% (HR, 2.39; 95% CI, 2.21 to 2.58) and similar to that of recipients of a nonpreemptive transplant with a KDPI of 51%-84% (HR, 1.61; 95% CI, 1.52 to 1.70).

CONCLUSIONS

Preemptive transplantation is associated with a lower risk of allograft failure, irrespective of KDPI, and preemptive transplants with KDPI ≥85% have comparable outcomes with nonpreemptive transplants with KDPI 51%-84%.

Time to Abolish Metrics That Sustain Systemic Racism in Kidney Allocation

This Viewpoint discusses how the Kidney Donor Profile Index (KDPI) in its current form is not fit to guide kidney allocation because it devalues organ donation by Black donors based on a weak association between donor race and kidney transplant failure.

Addressing sex-based disparities in solid organ transplantation in the United States - a conference report

Solid organ transplantation provides the best treatment for end-stage organ failure, but significant sex-based disparities in transplant access exist. On June 25, 2021, a virtual multidisciplinary conference was convened to address sex-based disparities in transplantation. Common themes contributing to sex-based disparities were noted across kidney, liver, heart, and lung transplantation, specifically the existence of barriers to referral and wait listing for women, the pitfalls of using serum creatinine, the issue of donor/recipient size mismatch, approaches to frailty and a higher prevalence of allosensitization among women. In addition, actionable solutions to improve access to transplantation were identified, including alterations to the current allocation system, surgical interventions on donor organs, and the incorporation of objective frailty metrics into the evaluation process. Key knowledge gaps and high-priority areas for future investigation were also discussed.

The living kidney donor profile index fails to discriminate allograft survival: implications for its use in kidney paired donation programs

The inclusion of blood group- and human leukocyte antigen-compatible donor and recipient pairs (CPs) in kidney paired donation (KPD) programs is a novel strategy to increase living donor (LD) transplantation. Transplantation from a donor with a better Living Donor Kidney Profile Index (LKDPI) may encourage CP participation in KPD programs. We undertook parallel analyses using data from the Scientific Registry of Transplant Recipients and the Australia and New Zealand Dialysis and Transplant Registry to determine whether the LKDPI discriminates death-censored graft survival (DCGS) between LDs. Discrimination was assessed by the following: (1) the change in the Harrell C statistic with the sequential addition of variables in the LKDPI equation to reference models that included only recipient factors and (2) whether the LKDPI discriminated DCGS among pairs of prognosis-matched LD recipients. The addition of the LKDPI to reference models based on recipient variables increased the C statistic by only 0.02. Among prognosis-matched pairs, the C statistic in Cox models to determine the association of the LKDPI with DCGS was no better than chance alone (0.51 in the Scientific Registry of Transplant Recipient and 0.54 in the Australia and New Zealand Dialysis and Transplant Registry cohorts). We conclude that the LKDPI does not discriminate DCGS and should not be used to promote CP participation in KPD programs.

The Living Kidney Donor Safety Study: Protocol of a Prospective Cohort Study

Background

Living kidney donation is considered generally safe in healthy individuals; however, there is a need to better understand the long-term effects of donation on blood pressure and kidney function.

Objectives

To determine the risk of hypertension in healthy, normotensive adults who donate a kidney compared with healthy, normotensive non-donors with similar indicators of baseline health. We will also compare the 2 groups on the rate of decline in kidney function, the risk of albuminuria, and changes in health-related quality of life.

Design Participants and Setting

Prospective cohort study of 1042 living kidney donors recruited before surgery from 17 transplant centers (12 in Canada and 5 in Australia) between 2004 and 2014. Non-donor participants (n = 396) included relatives or friends of the donor, or donor candidates who were ineligible to donate due to blood group or cross-match incompatibility. Follow-up will continue until 2021, and the main analysis will be performed in 2022. The anticipated median (25th, 75th percentile, maximum) follow-up time after donation is 7 years (6, 8, 15).

Measurements

Donors and non-donors completed the same schedule of measurements at baseline and follow-up (non-donors were assigned a simulated nephrectomy date). Annual measurements were obtained for blood pressure, estimated glomerular filtration rate (eGFR), albuminuria, patient-reported health-related quality of life, and general health.

Outcomes

Incident hypertension (a systolic/diastolic blood pressure ≥ 140/90 mm Hg or receipt of anti-hypertensive medication) will be adjudicated by a physician blinded to the participant's donation status. We will assess the rate of change in eGFR starting from 12 months after the nephrectomy date and the proportion who develop an albumin-to-creatinine ratio ≥3 mg/mmol (≥30 mg/g) in follow-up. Health-related quality of life will be assessed using the 36-item RAND health survey and the Beck Anxiety and Depression inventories.

Limitations

Donation-attributable hypertension may not manifest until decades after donation.

Conclusion

This prospective cohort study will estimate the attributable risk of hypertension and other health outcomes after living kidney donation.

Transplantation of Patients With Long Dialysis Vintage in the Current Deceased Donor Kidney Allocation System (KAS)

RATIONALE & OBJECTIVE

In 2014 the wait-time calculation for deceased donor kidney transplantation in the United States was changed from the date of first waitlisting to the date of first maintenance dialysis treatment with the aim of minimizing disparities in access to transplantation. This study examined the impact of this policy on access to transplantation, patient survival, and transplant outcomes among patients treated with maintenance dialysis for a prolonged duration before waitlisting.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

Patients identified in the US Renal Data System between 2008 and 2018 aged 18-70 years and in the 95th percentile of dialysis treatment duration (≥6.5 years) before waitlisting.

EXPOSURE

Waitlisting for transplantation before versus after implementation of the policy.

OUTCOME

Time from date of waitlisting to deceased donor transplantation and death, and from date of transplantation to all cause graft loss.

ANALYTICAL APPROACH

Univariate and multivariable time to event analyses.

RESULTS

Patients waitlisted after the policy change had a higher likelihood of deceased donor transplantation (HR, 3.12 [95% CI, 2.90-3.37]) and lower risk of death (HR, 0.74 [95% CI, 0.63-0.87]). The risk of graft loss was lower in the post-kidney allocation system (KAS) cohort (HR, 0.66 [95% CI, 0.55-0.80]). The proportion of adult patients treated with dialysis ≥6.5 years who were never waitlisted for transplantation remained high (73%) and did not decrease after the policy implementation.

LIMITATIONS

Cannot determine causality in this observational study.

CONCLUSIONS

The policy change was associated with an increase in deceased donor transplantation and marked improvement in patient survival for patients waitlisted after long periods of dialysis treatment without decreasing the utility of available deceased donor kidney supply. The policy was not associated with increased waitlisting of this disadvantaged population.

Global Estimates of Capacity for Kidney Transplantation in World Countries and Regions

BACKGROUND

Kidney transplantation (KT) is the optimal treatment for kidney failure and is associated with better quality of life and survival relative to dialysis. However, knowledge of the current capacity of countries to deliver KT is limited. This study reports on findings from the 2018 International Society of Nephrology Global Kidney Health Atlas survey, specifically addressing the availability, accessibility, and quality of KT across countries and regions.

METHODS

Data were collected from published online sources, and a survey was administered online to key stakeholders. All country-level data were analyzed by International Society of Nephrology region and World Bank income classification.

RESULTS

Data were collected via a survey in 182 countries, of which 155 answered questions pertaining to KT. Of these, 74% stated that KT was available, with a median incidence of 14 per million population (range: 0.04-70) and median prevalence of 255 per million population (range: 3-693). Accessibility of KT varied widely; even within high-income countries, it was disproportionately lower for ethnic minorities. Universal health coverage of all KT treatment costs was available in 31%, and 57% had a KT registry.

CONCLUSIONS

There are substantial variations in KT incidence, prevalence, availability, accessibility, and quality worldwide, with the lowest rates evident in low- and lower-middle income countries. Understanding these disparities will inform efforts to increase awareness and the adoption of practices that will ensure high-quality KT care is provided around the world.

Use and Outcomes of Induction Therapy in Well-Matched Kidney Transplant Recipients

BACKGROUND AND OBJECTIVES

The optimal induction treatment in low-immune risk kidney transplant recipients is uncertain. We therefore investigated the use and outcomes of induction immunosuppression in a low-risk cohort of patients who were well matched with their donor at HLA-A, -B, -DR, -DQB1 on the basis of serologic typing.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Our study was an observational study of first adult kidney-only transplant recipients in the United States recorded by the Organ Procurement and Transplant Network.

RESULTS

Among 2976 recipients, 57% were treated with T cell-depleting antibodies, 28% were treated with an IL-2 receptor antagonist, and 15% were treated without induction. There was no difference in allograft survival, death-censored graft survival, or death with function between patients treated with an IL-2 receptor antagonist and no induction therapy. In multivariable models, patients treated with T cell-depleting therapy had a similar risk of graft loss from any cause, including death (hazard ratio, 1.19; 95% confidence interval, 0.98 to 1.45), compared with patients treated with an IL-2 receptor antagonist or no induction. The findings were consistent in subgroup analyses of Black recipients, patients grouped by calculated panel reactive antibody, and donor source. The incidence of acute rejection at 1 year was low (≤5%) and did not vary between treatment groups.

CONCLUSIONS

Use of induction therapy with T cell-depleting therapy or IL-2 receptor antagonists in first kidney transplant recipients who are well matched with their donor at the HLA-A, -B, -DR, -DQB1 gene loci is not associated with improved post-transplant outcomes.

Bold policy changes are needed to meet the need for organ transplantation in India

Twenty-five years after India passed legislation to legalize brain death, deceased donor transplantation remains underdeveloped while the country has established formidable capacity for living donor transplantation. Because of a large number of potential deceased donors, there is hope that deceased donation could help meet India's enormous need for organ transplantation. However, significant policy and practical barriers limit progress. The vast majority of potential deceased donors are poor motor vehicle accident victims who present for care in hospitals without the necessary infrastructure or expertise to support deceased donation. In contrast, transplant infrastructure and expertise are concentrated in private hospitals and are only accessible to those with the ability to pay. Given these realities, the potential of deceased donor transplantation can only be recognized if Indians who are likely to donate organs are also provided access to transplantation. In this viewpoint, we review the current status of organ transplantation in India and propose new policies to establish a national organization to oversee deceased donor services in all states, to fund resources needed to support deceased donation, to leverage the existing living donor infrastructure to advance deceased donor transplantation, and call for establishment of government policy on funding for posttransplant care and immunosuppression.

Impact of Perioperative Complications on Living Kidney Donor Health-Related Quality of Life and Mental Health: Results From a Prospective Cohort Study

Background:

Although living kidney donation is safe, some donors experience perioperative complications.

Objective:

This study explored how perioperative complications affected donor-reported health-related quality of life, depression, and anxiety.

Design:

This research was a conducted as a prospective cohort study.

Setting:

Twelve transplant centers across Canada.

Patients:

A total of 912 living kidney donors were included in this study.

Measurements:

Short Form 36 health survey, Beck Depression Inventory and Beck Anxiety Inventory.

Methods:

Living kidney donors were prospectively enrolled predonation between 2009 to 2014. Donor perioperative complications were graded using the Clavien-Dindo classification system. Mental and physical health-related quality of life was assessed with the 3 measurements; measurements were taken predonation and at 3- and 12-months postdonation.

Results:

Seventy-four donors (8%) experienced a perioperative complication; most were minor (n = 67 [91%]), and all minor complications resolved before hospital discharge. The presence (versus absence) of a perioperative complication was associated with lower mental health-related quality of life and higher depression symptoms 3-month postdonation; neither of these differences persisted at 12-month. Perioperative complications were not associated with any changes in physical health-related quality of life or anxiety 3-month postdonation.

Limitations:

Minor complications may have been missed and information on complications postdischarge were not collected. No minimal clinically significant change has been defined for kidney donors across the 3 measurements.

Conclusions:

These findings highlight a potential opportunity to better support the psychosocial needs of donors who experience perioperative complications in the months following donation.

Trial registration:

NCT00319579 and NCT00936078.

Early Corticosteroid Cessation vs Long-term Corticosteroid Therapy in Kidney Transplant Recipients: Long-term Outcomes of a Randomized Clinical Trial

Importance

The complications of corticosteroids make the inclusion of these drugs in immunosuppressive protocols for kidney transplant patients undesirable. However, cessation of corticosteroids is associated with a higher risk of short-term rejection, and the long-term outcomes of patients withdrawn from corticosteroids remain uncertain.

Objective

To compare long-term kidney transplant outcomes of patients randomized to continue or withdraw corticosteroids.

Design, Setting, and Participants

This prospective multicenter randomized double-blind placebo-controlled trial was conducted between November 1999 and December 2002 with linkage to a mandatory national registry with validated outcome ascertainment until June 8, 2018. The study included 28 kidney transplant centers in the United States, including 386 low- to moderate-immune risk adult recipients of a living or deceased donor kidney transplant without delayed graft function or short-term rejection in the first week after transplant. Analyses were intention to treat. Analysis began September 2018 and ended June 2019.

Interventions

Patients were randomized to receive tacrolimus and mycophenolate mofetil with or without corticosteroids 7 days after transplant.

Main Outcomes and Measures

Kidney allograft failure from any cause including death and allograft failure censored for patient death defined by the requirement for long-term dialysis or repeat transplant.

Results

Of 385 patients, 191 were assigned to withdraw from corticosteroids (mean [SD] age, 46.5 [12.1] years), and 194 patients were assigned to continued corticosteroids (mean [SD] age, 46.3 [12.6] years). The median (interquartile range) follow-up time was 15.8 (12.0-16.3) years after transplant. The adjusted hazard ratios of allograft failure from any cause including death was 0.83 (95% CI, 0.62-1.10; P = .19) and for allograft failure censored for patient death was 0.78 (95% CI, 0.52-1.19; P = .25) and did not differ between the patients assigned to withdraw from corticosteroids vs assigned to continued corticosteroids. Results were consistent in a per-protocol analysis among 223 patients who continued the trial-assigned treatment of corticosteroid withdrawal (n = 114) or corticosteroids (n = 109) through at least 5 years after transplant. The outcomes of trial participants in either treatment group did not differ from similarly treated contemporary registry patients who met trial eligibility criteria and were treated with the same immunosuppressive drugs.

Conclusions and Relevance

Long-term corticosteroids may not be necessary as part of a calcineurin-based multiple drug immunosuppressive regimen in low- to moderate-immune risk kidney transplant recipients.

Pretransplant Calculated Panel Reactive Antibody in the Absence of Donor-Specific Antibody and Kidney Allograft Survival

BACKGROUND AND OBJECTIVES

Panel reactive antibody informs the likelihood of finding an HLA-compatible donor for transplant candidates, but has historically been associated with acute rejection and allograft survival because testing methods could not exclude the presence of concomitant donor-specific antibodies. Despite new methods to exclude donor-specific antibodies, panel reactive antibody continues to be used to determine the choice of induction and maintenance immunosuppression. The study objective was to determine the clinical relevance of panel reactive antibody in the absence of donor-specific antibodies.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Retrospective observational study of kidney allograft survival among 4058 zero HLA-A-, B-, DR-, and DQB1-mismatched transplant recipients without antibodies to donor kidney antigens encoded by these HLA gene loci.

RESULTS

Among 4058 first and repeat transplant recipients, patients with calculated panel reactive antibody (cPRA) 1%-97% were not at higher risk of transplant failure, compared with patients with cPRA of 0% (death censored graft loss: hazard ratio, 1.07; 95% confidence interval, 0.82 to 1.41). Patients with cPRA ≥98% had a higher risk of graft loss from any cause including death (hazard ratio, 1.39; 95% confidence interval, 1.08 to 1.79) and death censored allograft failure (hazard ratio, 1.78; 95% confidence interval, 1.27 to 2.49). In stratified analyses, the higher risk of graft loss among patients with cPRA ≥98% was only observed among repeat, but not first, transplant recipients. In subgroup analysis, there was no association between cPRA and graft loss among living related transplant recipients.

CONCLUSIONS

Calculated panel reactive antibody is poorly associated with post-transplant immune reactivity to the allograft in the absence of donor-specific antibody.

PODCAST

This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2021_01_25_CJN13640820_final.mp3.

The association of pretransplant dialysis exposure with transplant failure is dependent on the state-specific rate of dialysis mortality

Longer pretransplant dialysis exposure is associated with a higher risk of transplant failure. Whether patients who receive dialysis in a region with a higher rate of dialysis mortality are a higher risk for transplant failure is unknown. Adjusted state-specific hemodialysis mortality rates were determined in 3-year intervals among prevalent dialysis patients in the United States between 1995 and 2012. The effect of state- and period-specific dialysis mortality on the association of pretransplant dialysis exposure with transplant survival through December 2017 was determined using multivariable models. Dialysis mortality within states ranged from 128 deaths/1000 patient-years to 330 deaths/1000 patient-years. Each additional year of dialysis was associated with a 4% higher risk of transplant failure in states within the lowest quartile of dialysis mortality, compared with an 8% higher risk in states within the highest quartile of dialysis mortality. Patients who received pretransplant dialysis treatment in a state with a high rate of dialysis mortality are at a higher risk for transplant failure compared with patients with the same duration of pretransplant dialysis treatment in a state with a lower mortality rate. The findings may have implications for dialysis care in transplant candidates and the design of future outcome metrics.

Nomenclature for kidney function and disease: report of a Kidney Disease: Improving Global Outcomes (KDIGO) Consensus Conference

The worldwide burden of kidney disease is rising, but public awareness remains limited, underscoring the need for more effective communication by stakeholders in the kidney health community. Despite this need for clarity, the nomenclature for describing kidney function and disease lacks uniformity. In June 2019, Kidney Disease: Improving Global Outcomes (KDIGO) convened a Consensus Conference with the goal of standardizing and refining the nomenclature used in the English language to describe kidney function and disease, and of developing a glossary that could be used in scientific publications. Guiding principles of the conference were that the revised nomenclature should be patient-centered, precise, and consistent with nomenclature used in the KDIGO guidelines. Conference attendees reached general consensus on the following recommendations: (i) to use "kidney" rather than "renal" or "nephro-" when referring to kidney disease and kidney function; (ii) to use "kidney failure" with appropriate descriptions of presence or absence of symptoms, signs, and treatment, rather than "end-stage kidney disease"; (iii) to use the KDIGO definition and classification of acute kidney diseases and disorders (AKD) and acute kidney injury (AKI), rather than alternative descriptions, to define and classify severity of AKD and AKI; (iv) to use the KDIGO definition and classification of chronic kidney disease (CKD) rather than alternative descriptions to define and classify severity of CKD; and (v) to use specific kidney measures, such as albuminuria or decreased glomerular filtration rate (GFR), rather than "abnormal" or "reduced" kidney function to describe alterations in kidney structure and function. A proposed 5-part glossary contains specific items for which there was general agreement. Conference attendees acknowledged limitations of the recommendations and glossary, but they considered standardization of scientific nomenclature to be essential for improving communication.

Nomenclature for kidney function and disease: report of a Kidney Disease: Improving Global Outcomes (KDIGO) Consensus Conference

The worldwide burden of kidney disease is rising, but public awareness remains limited, underscoring the need for more effective communication by stakeholders in the kidney health community. Despite this need for clarity, the nomenclature for describing kidney function and disease lacks uniformity. In June 2019, Kidney Disease: Improving Global Outcomes (KDIGO) convened a Consensus Conference with the goal of standardizing and refining the nomenclature used in the English language to describe kidney function and disease, and of developing a glossary that could be used in scientific publications. Guiding principles of the conference were that the revised nomenclature should be patient-centered, precise, and consistent with nomenclature used in the KDIGO guidelines. Conference attendees reached general consensus on the following recommendations: (i) to use "kidney" rather than "renal" or "nephro-" when referring to kidney disease and kidney function; (ii) to use "kidney failure" with appropriate descriptions of presence or absence of symptoms, signs, and treatment, rather than "end-stage kidney disease"; (iii) to use the KDIGO definition and classification of acute kidney diseases and disorders (AKD) and acute kidney injury (AKI), rather than alternative descriptions, to define and classify severity of AKD and AKI; (iv) to use the KDIGO definition and classification of chronic kidney disease (CKD) rather than alternative descriptions to define and classify severity of CKD; and (v) to use specific kidney measures, such as albuminuria or decreased glomerular filtration rate (GFR), rather than "abnormal" or "reduced" kidney function to describe alterations in kidney structure and function. A proposed 5-part glossary contains specific items for which there was general agreement. Conference attendees acknowledged limitations of the recommendations and glossary, but they considered standardization of scientific nomenclature to be essential for improving communication.

Chronic Kidney Disease and Coronary Artery Disease: JACC State-of-the-Art Review

Chronic kidney disease (CKD) is a major risk factor for coronary artery disease (CAD). As well as their high prevalence of traditional CAD risk factors, such as diabetes and hypertension, persons with CKD are also exposed to other nontraditional, uremia-related cardiovascular disease risk factors, including inflammation, oxidative stress, and abnormal calcium-phosphorus metabolism. CKD and end-stage kidney disease not only increase the risk of CAD, but they also modify its clinical presentation and cardinal symptoms. Management of CAD is complicated in CKD patients, due to their likelihood of comorbid conditions and potential for side effects during interventions. This summary of the Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference on CAD and CKD (including end-stage kidney disease and transplant recipients) seeks to improve understanding of the epidemiology, pathophysiology, diagnosis, and treatment of CAD in CKD and to identify knowledge gaps, areas of controversy, and priorities for research.

Economic Evaluation of Extending Medicare Immunosuppressive Drug Coverage for Kidney Transplant Recipients in the Current Era

BACKGROUND

Kidney transplant recipients must take immunosuppressant drugs to prevent rejection and maintain transplant function. Medicare coverage of immunosuppressant drugs for kidney transplant recipients ceases 36 months after transplantation, potentially increasing the risk of transplant failure. A contemporary economic analysis of extending Medicare coverage for the duration of transplant survival using current costs of immunosuppressant medications in the era of generic equivalents may inform immunosuppressant drug policy.

METHODS

A Markov model was used to determine the incremental cost and effectiveness of extending Medicare coverage for immunosuppressive drugs over the duration of transplant survival, compared with the current policy of 36-month coverage, from the perspective of the Medicare payer. The expected improvement in transplant survival by extending immunosuppressive drug coverage was estimated from a cohort of privately insured transplant recipients who receive lifelong immunosuppressant drug coverage compared with a cohort of Medicare-insured transplant recipients, using multivariable survival analysis.

RESULTS

Extension of immunosuppression Medicare coverage for kidney transplant recipients led to lower costs of -$3077 and 0.37 additional quality-adjusted life years (QALYs) per patient. When the improvement in transplant survival associated with extending immunosuppressant coverage was reduced to 50% of that observed in privately insured patients, the strategy of extending drug coverage had an incremental cost-utility ratio of $51,694 per QALY gained. In a threshold analysis, the extension of immunosuppression coverage was cost-effective at a willingness-to-pay threshold of $100,000, $50,000, and $0 per QALY if it results in a decrease in risk of transplant failure of 5.5%, 7.8%, and 13.3%, respectively.

CONCLUSIONS

Extending immunosuppressive drug coverage under Medicare from the current 36 months to the duration of transplant survival will result in better patient outcomes and cost-savings, and remains cost-effective if only a fraction of anticipated benefit is realized.

Referral for Kidney Transplantation in Canadian Provinces

BACKGROUND

Patient referral to a transplant facility, a prerequisite for dialysis-treated patients to access kidney transplantation in Canada, is a subjective process that is not recorded in national dialysis or transplant registries. Patients who may benefit from transplant may not be referred.

METHODS

In this observational study, we prospectively identified referrals for kidney transplant in adult patients between June 2010 and May 2013 in 12 transplant centers, and linked these data to information on incident dialysis patients in a national registry.

RESULTS

Among 13,184 patients initiating chronic dialysis, the cumulative incidence of referral for transplant was 17.3%, 24.0%, and 26.8% at 1, 2, and 3 years after dialysis initiation, respectively; the rate of transplant referral was 15.8 per 100 patient-years (95% confidence interval, 15.1 to 16.4). Transplant referral varied more than three-fold between provinces, but it was not associated with the rate of deceased organ donation or median waiting time for transplant in individual provinces. In a multivariable model, factors associated with a lower likelihood of referral included older patient age, female sex, diabetes-related ESKD, higher comorbid disease burden, longer durations (>12.0 months) of predialysis care, and receiving dialysis at a location >100 km from a transplant center. Median household income and non-Caucasian race were not associated with a lower likelihood of referral.

CONCLUSIONS

Referral rates for transplantation varied widely between Canadian provinces but were not lower among patients of non-Caucasian race or with lower socioeconomic status. Standardization of transplantation referral practices and ongoing national reporting of referral may decrease disparities in patient access to kidney transplant.

Canadian-Australasian Randomised trial of screening kidney transplant candidates for coronary artery disease-A trial protocol for the CARSK study

Transplantation is the preferred treatment for patients with kidney failure, but the need exceeds the supply of transplantable kidneys, and patients routinely wait >5 years on dialysis for a transplant. Coronary artery disease (CAD) is common in kidney failure and can exclude patients from transplantation or result in death before or after transplantation. Screening asymptomatic patients for CAD using noninvasive tests prior to wait-listing and at regular intervals (ie, annually) after wait-listing until transplantation is the established standard of care and is justified by the need to avoid adverse patient outcomes and loss of organs. Patients with abnormal screening tests undergo coronary angiography, and those with critical stenoses are revascularized. Screening is potentially harmful because patients may be excluded or delayed from transplantation, and complications after revascularization are more frequent in this population. CARSK will test the hypothesis that eliminating screening tests for occult CAD after wait-listing is not inferior to regular screening for the prevention of major adverse cardiac events defined as the composite of cardiovascular death, nonfatal myocardial infarction, urgent revascularization, and hospitalization for unstable angina. Secondary outcomes include the transplant rate, safety measures, and the cost-effectiveness of screening. Enrolment of 3,306 patients over 3 years is required, with patients followed for up to 5 years during wait-listing and for 1 year after transplantation. By validating or refuting the use of screening tests during wait-listing, CARSK will ensure judicious use of health resources and optimal patient outcomes.

Access to Kidney Transplantation after a Failed First Kidney Transplant and Associations with Patient and Allograft Survival: An Analysis of National Data to Inform Allocation Policy

BACKGROUND AND OBJECTIVES

Patients who have failed a transplant are at increased risk of repeat transplant failure. We determined access to transplantation and transplant outcomes in patients with and without a history of transplant failure.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In this observational study of national data, the proportion of waitlisted patients and deceased donor transplant recipients with transplant failure was determined before and after the new kidney allocation system. Among patients initiating maintenance dialysis between May 1995 and December 2014, the likelihood of deceased donor transplantation was determined in patients with (n=27,459) and without (n=1,426,677) a history of transplant failure. Among transplant recipients, allograft survival, the duration of additional kidney replacement therapy required within 10 years of transplantation, and the association of transplantation versus dialysis with mortality was determined in patients with and without a history of transplant failure.

RESULTS

The proportion of waitlist candidates (mean 14%) and transplant recipients (mean 12%) with transplant failure did not increase after the new kidney allocation system. Among patients initiating maintenance dialysis, transplant-failure patients had a higher likelihood of transplantation (hazard ratio [HR], 1.16; 95% confidence interval [95% CI], 1.12 to 1.20; P<0.001). Among transplant recipients, transplant-failure patients had a higher likelihood of death-censored transplant failure (HR, 1.44; 95% CI, 1.34 to 1.54; P<0.001) and a greater need for additional kidney replacement therapy required within 10 years after transplantation (mean, 9.0; 95% CI, 5.4 to 12.6 versus mean, 2.1; 95% CI, 1.5 to 2.7 months). The association of transplantation versus dialysis with mortality was clinically similar in waitlisted patients with (HR, 0.32; 95% CI, 0.29 to 0.35; P<0.001) and without transplant failure (HR, 0.40; 95% CI, 0.39 to 0.41; P<0.001).

CONCLUSIONS

Transplant-failure patients initiating maintenance dialysis have a higher likelihood of transplantation than transplant-naïve patients. Despite inferior death-censored transplant survival, transplantation was associated with a similar reduction in the risk of death compared with treatment with dialysis in patients with and without a prior history of transplant failure.

Clinicians' attitudes and approaches to evaluating the potential living kidney donor-recipient relationship: An interview study

AIM

Careful assessment of the potential donor-recipient relationship is recommended by guidelines to prevent undue coercion, and to ensure realistic expectations and genuine motivations. However, relationships are complex, nuanced and value-laden, and can be challenging to evaluate in living kidney donation. We aimed to describe the attitudes and approaches of transplant clinicians towards assessing the relationship between potential living kidney donors and their recipients.

METHODS

Semi-structured interviews were conducted with 54 transplant clinicians (nephrologists, surgeons, coordinators, social workers, psychiatrists and psychologists) from 32 transplant centres across nine countries including Australia, United States, Canada and New Zealand. Transcripts were analyzed thematically.

RESULTS

Four themes were identified: protecting against vulnerability and premature decisions (ensuring genuine motivation, uncovering precarious dynamics and pre-empting conflict, shared accountability, relying on specialty psychosocial expertise, trusting intimate bonds, tempering emotional impulsivity); safeguarding against coercion (discerning power imbalance, justified inquiry, awareness of impression management); minimizing potential threat to relationships (preserving the bond, giving equitable attention to donors and recipients, ensuring realistic expectations); and ambiguities in making judgments (adjudicating appropriateness and authenticity of relationships, questioning professional intervening, uncertainties in subjective and emotional assessments).

CONCLUSIONS

Clinicians felt ethically compelled to minimize the risk of undue coercion and to protect donors and recipients when evaluating the donor-recipient relationship. However, disentangling voluntariness and altruism from potential undisclosed pressures to enact societal and family duty, making decisions within this complex, multi-stakeholder context, and avoiding the imposition of undue paternalism and donor autonomy, were challenging. Multidisciplinary expertise and practical strategies for managing uncertainties are required.

Financial Costs Incurred by Living Kidney Donors: A Prospective Cohort Study

BACKGROUND

Approximately 40% of the kidneys for transplant worldwide come from living donors. Despite advantages of living donor transplants, rates have stagnated in recent years. One possible barrier may be costs related to the transplant process that potential willing donors may incur for travel, parking, accommodation, and lost productivity.

METHODS

To better understand and quantify the financial costs incurred by living kidney donors, we conducted a prospective cohort study, recruiting 912 living kidney donors from 12 transplant centers across Canada between 2009 and 2014; 821 of them completed all or a portion of the costing survey. We report microcosted total, out-of-pocket, and lost productivity costs (in 2016 Canadian dollars) for living kidney donors from donor evaluation start to 3 months after donation. We examined costs according to (1) the donor's relationship with their recipient, including spousal (donation to a partner), emotionally related nonspousal (friend, step-parent, in law), or genetically related; and (2) donation type (directed, paired kidney, or nondirected).

RESULTS

Living kidney donors incurred a median (75th percentile) of $1254 ($2589) in out-of-pocket costs and $0 ($1908) in lost productivity costs. On average, total costs were $2226 higher in spousal compared with emotionally related nonspousal donors (P=0.02) and $1664 higher in directed donors compared with nondirected donors (P<0.001). Total costs (out-of-pocket and lost productivity) exceeded $5500 for 205 (25%) donors.

CONCLUSIONS

Our results can be used to inform strategies to minimize the financial burden of living donation, which may help improve the donation experience and increase the number of living donor kidney transplants.

Cost-effectiveness of using kidneys from hepatitis C nucleic acid test-positive donors for transplantation in hepatitis C-negative recipients

Kidneys from deceased donors who are hepatitis C virus (HCV) nucleic acid test positive are infrequently used for transplantation in HCV-negative patients due to concerns about disease transmission. With the development of direct-acting antivirals (DAAs) for HCV, there is now potential to use these kidneys in HCV-negative candidates. However, the high cost of DAAs poses a challenge to adoption of this strategy. We created a Markov model to examine the cost-effectiveness of using deceased donors infected with HCV for kidney transplantation in uninfected waitlist candidates. In the primary analysis, this strategy was cost saving and improved health outcomes compared to remaining on the waitlist for an additional 2 or more years to receive a HCV-negative transplant. The strategy was also cost-effective with an incremental cost-effectiveness ratio of $56 018 per quality-adjusted life year (QALY) from the payer perspective, and $4647 per QALY from the societal perspective, compared to remaining on the waitlist for 1 additional year. The results were consistent in 1-way and probabilistic sensitivity analyses. We conclude that the use of kidneys from deceased donors with HCV infection is likely to lead to improved clinical outcomes at reduced cost for HCV-negative transplant candidates.

Identifying Outcomes that Are Important to Living Kidney Donors: A Nominal Group Technique Study

BACKGROUND AND OBJECTIVES

Living kidney donor candidates accept a range of risks and benefits when they decide to proceed with nephrectomy. Informed consent around this decision assumes they receive reliable data about outcomes they regard as critical to their decision making. We identified the outcomes most important to living kidney donors and described the reasons for their choices.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Previous donors were purposively sampled from three transplant units in Australia (Sydney and Melbourne) and Canada (Vancouver). In focus groups using the nominal group technique, participants identified outcomes of donation, ranked them in order of importance, and discussed the reasons for their preferences. An importance score was calculated for each outcome. Qualitative data were analyzed thematically.

RESULTS

Across 14 groups, 123 donors aged 27-78 years identified 35 outcomes. Across all participants, the ten highest ranked outcomes were kidney function (importance=0.40, scale 0-1), time to recovery (0.27), surgical complications (0.24), effect on family (0.22), donor-recipient relationship (0.21), life satisfaction (0.18), lifestyle restrictions (0.18), kidney failure (0.14), mortality (0.13), and acute pain/discomfort (0.12). Kidney function and kidney failure were more important to Canadian participants, compared with Australian donors. The themes identified included worthwhile sacrifice, insignificance of risks and harms, confidence and empowerment, unfulfilled expectations, and heightened susceptibility.

CONCLUSIONS

Living kidney donors prioritized a range of outcomes, with the most important being kidney health and the surgical, lifestyle, functional, and psychosocial effects of donation. Donors also valued improvements to their family life and donor-recipient relationship. There were clear regional differences in the rankings.

Concentrations of Trace Elements and Clinical Outcomes in Hemodialysis Patients: A Prospective Cohort Study

BACKGROUND AND OBJECTIVES

Deficiency of essential trace elements and excess of potentially toxic trace elements are common in patients on hemodialysis. Whether these abnormalities are associated with poor outcomes is unknown but worth investigating, because they are potentially treatable.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We did a prospective longitudinal study of 1278 patients on incident hemodialysis, assessing blood concentrations of 25 trace elements at baseline. We used adjusted logistic regression to evaluate the association between trace element status and four outcomes (death, cardiovascular events, systemic infection, and hospitalization). A priori hypotheses concerned (1) deficiency of zinc, selenium, and manganese and (2) excess of lead, arsenic, and mercury. Concentrations of the other 19 elements were tested in hypothesis-generating analyses.

RESULTS

Over 2 years of follow-up, 260 (20%) patients died, 285 (24%) experienced a cardiovascular event, 117 (10%) were hospitalized for systemic infection, and 928 (77%) were hospitalized for any cause. Lower concentrations of zinc or manganese and higher concentrations of lead, arsenic, or mercury were not independently associated with higher risk of clinical outcomes. Lower concentrations of selenium were strongly and independently associated with death (odds ratio, 0.86 per decile; 99.2% confidence interval, 0.80 to 0.93) and all-cause hospitalization (odds ratio, 0.92 per decile; 99.2% confidence interval, 0.86 to 0.98). In exploratory analyses, higher copper concentrations were significantly associated with higher risk of death (odds ratio, 1.07 per decile; 99.2% confidence interval, 1.00 to 1.15), and cadmium levels in the highest decile were associated with higher risk of death (odds ratio, 1.89; 99.2% confidence interval, 1.06 to 3.38).

CONCLUSIONS

Lower levels of zinc or manganese and higher concentrations of lead, arsenic, or mercury were not associated with higher risk of clinical outcomes, but lower concentrations of selenium were strongly and independently associated with the risks of death and hospitalization.

Clinicians' and researchers' perspectives on establishing and implementing core outcomes in haemodialysis: semistructured interview study

OBJECTIVES

To describe the perspectives of clinicians and researchers on identifying, establishing and implementing core outcomes in haemodialysis and their expected impact.

DESIGN

Face-to-face, semistructured interviews; thematic analysis.

STETTING

Twenty-seven centres across nine countries.

PARTICIPANTS

Fifty-eight nephrologists (42 (72%) who were also triallists).

RESULTS

We identified six themes: reflecting direct patient relevance and impact (survival as the primary goal of dialysis, enabling well-being and functioning, severe consequences of comorbidities and complications, indicators of treatment success, universal relevance, stakeholder consensus); amenable and responsive to interventions (realistic and possible to intervene on, differentiating between treatments); reflective of economic burden on healthcare; feasibility of implementation (clarity and consistency in definition, easily measurable, requiring minimal resources, creating a cultural shift, aversion to intensifying bureaucracy, allowing justifiable exceptions); authoritative inducement and directive (endorsement for legitimacy, necessity of buy-in from dialysis providers, incentivising uptake); instituting patient-centredness (explicitly addressing patient-important outcomes, reciprocating trial participation, improving comparability of interventions for decision-making, driving quality improvement and compelling a focus on quality of life).

CONCLUSIONS

Nephrologists emphasised that core outcomes should be relevant to patients, amenable to change, feasible to implement and supported by stakeholder organisations. They expected core outcomes would improve patient-centred care and outcomes.