Moving closer to understanding the risks of living kidney donation

Alternate Choice Organ Counselling in Altruistic Non-Directed Solid Organ Donation: An Ethical Analysis

INTRODUCTION

Currently, recruitment of non-directed altruistic (NDA) kidney and liver lobe donors in the UK regards these individuals as potential NDA donors of the particular organ type they initially express an interest in donating. Conceptualising these individuals instead as potential NDA donors of either a kidney or a liver lobe would require them to be counselled on both kidney donation and liver lobe donation. This can be referred to as 'alternate choice organ counselling'.

METHODS

This paper conducts an ethical analysis of alternate choice organ counselling using the ethical framework of Principlism, and suggests changes to current policy and practice, accordingly.

FINDINGS

This paper finds multiple strong ethical reasons to carry out alternate choice organ counselling for potential NDA donors of kidneys or liver lobes: the duty to respect autonomy requires alternate choice organ counselling such that the potential donor's decision to become a NDA donor of a particular organ type is fully informed; the duty of non-maleficence requires alternate choice organ counselling such that the harm subjected to the donor through living donation can be minimised (although such counselling might generate serial NDA donors, which would expose them to greater total harm); the asymmetry in the degree to which the living kidney and living liver lobe donation mechanisms promote justice requires alternate choice organ counselling for potential donors who wish to maximise the utility of their single NDA donation; finally, alternate choice organ counselling is likely to promote beneficence in potential NDA donors.

DISCUSSION

This paper finds ethical reasons for potential NDA donors to be conceptualised as potential NDA donors of either a kidney or liver lobe, and for these individuals to be provided with alternate choice organ counselling. Suggestions on how this might be delivered in practice are offered, and the necessary further quantitative and qualitative research outlined.

Evaluation and Long-Term Follow-Up of Living Kidney Donors

The evaluation of living kidney donor candidates is a complex and lengthy process. Donor candidates face geographic and socioeconomic barriers to completing donor evaluation. Inequities in access to living donations persist. With a growing demand for kidney transplants and a shortage of living donors, transplant centers are more permissive of accepting less-than-ideal donor candidates. Donors have an increased lifetime risk of kidney failure, but the absolute risk increase is small. Efforts are needed to support donor candidates to complete donor nephrectomy safely and efficiently and receive optimal follow-up care to prevent risk factors for kidney disease and detect complications early. In this article, the authors address key elements of donor kidney evaluation, including current living donation policy requirements and transplant center practices. The authors present a simplified comprehensive practical approach to help guide providers in completing donor evaluation and follow-up care with best outcomes possible.

Research progress on multiple cell death pathways of podocytes in diabetic kidney disease

Diabetic kidney disease (DKD) is the main cause of end-stage renal disease, and its clinical manifestations are progressive proteinuria, decreased glomerular filtration rate, and renal failure. The injury and death of glomerular podocytes are the keys to DKD. Currently, a variety of cell death modes have been identified in podocytes, including apoptosis, autophagy, endoplasmic reticulum (ER) stress, pyroptosis, necroptosis, ferroptosis, mitotic catastrophe, etc. The signaling pathways leading to these cell death processes are interconnected and can be activated simultaneously or in parallel. They are essential for cell survival and death that determine the fate of cells. With the deepening of the research on the mechanism of cell death, more and more researchers have devoted their attention to the underlying pathologic research and the drug therapy research of DKD. In this paper, we discussed the podocyte physiologic role and DKD processes. We also provide an overview of the types and specific mechanisms involved in each type of cell death in DKD, as well as related targeted therapy methods and drugs are reviewed. In the last part we discuss the complexity and potential crosstalk between various modes of cell death, which will help improve the understanding of podocyte death and lay a foundation for new and ideal targeted therapy strategies for DKD treatment in the future.

How the websites of high-volume US centers address the risks of living kidney donation

BACKGROUND

The websites of US transplant centers may be a source of information about the renal risks of potential living kidney donors.

METHODS

To include only likely best practices, we surveyed websites of centers that performed at least 50 living donor kidney transplants per year. We tabulated how risks were conveyed regarding loss of eGFR at donation, the adequacy of long-term ESRD risk data, long-term donor mortality, minority donor ESRD risk, concerns about hyperfiltration injury versus the risk of end-stage kidney diseases, comparisons of ESRD risks in donors to population risks, the increased risks of younger donors, an effect of the donation itself to increase risk, quantifying risks over specific intervals, and a lengthening list of small post-donation medical risks and metabolic changes of uncertain significance.

RESULTS

While websites had no formal obligation to address donor risks, many offered abundant information. Some conveyed OPTN-mandated requirements for counseling individual donor candidates. While actual wording often varied, there was general agreement on many issues. We occasionally noted clear-cut differences among websites in risk characterization and other outliers.

CONCLUSIONS

The websites of the most active US centers offer insights into how transplant professionals view living kidney donor risk. Website content may merit further study.

The Minnesota attributable risk of kidney donation (MARKD) study: a retrospective cohort study of long-term (> 50 year) outcomes after kidney donation compared to well-matched healthy controls

BACKGROUND

There is uncertainty about the long-term risks of living kidney donation. Well-designed studies with controls well-matched on risk factors for kidney disease are needed to understand the attributable risks of kidney donation.

METHODS

The goal of the Minnesota Attributable Risk of Kidney Donation (MARKD) study is to compare the long-term (> 50 years) outcomes of living donors (LDs) to contemporary and geographically similar controls that are well-matched on health status. University of Minnesota (n = 4022; 1st transplant: 1963) and Mayo Clinic LDs (n = 3035; 1st transplant: 1963) will be matched to Rochester Epidemiology Project (REP) controls (approximately 4 controls to 1 donor) on the basis of age, sex, and race/ethnicity. The REP controls are a well-defined population, with detailed medical record data linked between all providers in Olmsted and surrounding counties, that come from the same geographic region and era (early 1960s to present) as the donors. Controls will be carefully selected to have health status acceptable for donation on the index date (date their matched donor donated). Further refinement of the control group will include confirmed kidney health (e.g., normal serum creatinine and/or no proteinuria) and matching (on index date) of body mass index, smoking history, family history of chronic kidney disease, and blood pressure. Outcomes will be ascertained from national registries (National Death Index and United States Renal Data System) and a new survey administered to both donors and controls; the data will be supplemented by prior surveys and medical record review of donors and REP controls. The outcomes to be compared are all-cause mortality, end-stage kidney disease, cardiovascular disease and mortality, estimated glomerular filtration rate (eGFR) trajectory and chronic kidney disease, pregnancy risks, and development of diseases that frequently lead to chronic kidney disease (e.g. hypertension, diabetes, and obesity). We will additionally evaluate whether the risk of donation differs based on baseline characteristics.

DISCUSSION

Our study will provide a comprehensive assessment of long-term living donor risk to inform candidate living donors, and to inform the follow-up and care of current living donors.

Prediction of measured GFR after living kidney donation from pre-donation parameters

BACKGROUND

One of the challenges in living kidney donor screening is to estimate remaining kidney function after donation. Here we developed a new model to predict post-donation measured glomerular filtration rate (mGFR) from pre-donation serum creatinine, age and sex.

METHODS

In the prospective development cohort (TransplantLines, n = 511), several prediction models were constructed and tested for accuracy, precision and predictive capacity for short- and long-term post-donation 125I-iothalamate mGFR. The model with optimal performance was further tested in specific high-risk subgroups (pre-donation eGFR <90 mL/min/1.73 m2, a declining 5-year post-donation mGFR slope or age >65 years) and validated in internal (n = 509) and external (Mayo Clinic, n = 1087) cohorts.

RESULTS

In the development cohort, pre-donation estimated GFR (eGFR) was 86 ± 14 mL/min/1.73 m2 and post-donation mGFR was 64 ± 11 mL/min/1.73 m2. Donors with a pre-donation eGFR ≥90 mL/min/1.73 m2 (present in 43%) had a mean post-donation mGFR of 69 ± 10 mL/min/1.73 m2 and 5% of these donors reached an mGFR <55 mL/min/1.73 m2. A model using pre-donation serum creatinine, age and sex performed optimally, predicting mGFR with good accuracy (mean bias 2.56 mL/min/1.73 m2, R2 = 0.29, root mean square error = 11.61) and precision [bias interquartile range (IQR) 14 mL/min/1.73 m2] in the external validation cohort. This model also performed well in donors with pre-donation eGFR <90 mL/min/1.73 m2 [bias 0.35 mL/min/1.73 m2 (IQR 10)], in donors with a negative post-donation mGFR slope [bias 4.75 mL/min/1.73 m2 (IQR 13)] and in donors >65 years of age [bias 0.003 mL/min/1.73 m2 (IQR 9)].

CONCLUSIONS

We developed a novel post-donation mGFR prediction model based on pre-donation serum creatinine, age and sex.

Recommendations for living donor kidney transplantation

This Guide for Living Donor Kidney Transplantation (LDKT) has been prepared with the sponsorship of the Spanish Society of Nephrology (SEN), the Spanish Transplant Society (SET), and the Spanish National Transplant Organization (ONT). It updates evidence to offer the best chronic renal failure treatment when a potential living donor is available. The core aim of this Guide is to supply clinicians who evaluate living donors and transplant recipients with the best decision-making tools, to optimise their outcomes. Moreover, the role of living donors in the current KT context should recover the level of importance it had until recently. To this end the new forms of incompatible HLA and/or ABO donation, as well as the paired donation which is possible in several hospitals with experience in LDKT, offer additional ways to treat renal patients with an incompatible donor. Good results in terms of patient and graft survival have expanded the range of circumstances under which living renal donors are accepted. Older donors are now accepted, as are others with factors that affect the decision, such as a borderline clinical history or alterations, which when evaluated may lead to an additional number of transplantations. This Guide does not forget that LDKT may lead to risk for the donor. Pre-donation evaluation has to centre on the problems which may arise over the short or long-term, and these have to be described to the potential donor so that they are able take them into account. Experience over recent years has led to progress in risk analysis, to protect donors' health. This aspect always has to be taken into account by LDKT programmes when evaluating potential donors. Finally, this Guide has been designed to aid decision-making, with recommendations and suggestions when uncertainties arise in pre-donation studies. Its overarching aim is to ensure that informed consent is based on high quality studies and information supplied to donors and recipients, offering the strongest possible guarantees.

Long-term Medical Outcomes of Living Kidney Donors

Historically, to minimize risks, living kidney donors have been highly selected and healthy. Operative risks are well-defined, yet concern remains about long-term risks. In the general population, even a mild reduction in glomerular filtration rate (GFR) is associated with cardiovascular disease, chronic kidney disease, and end-stage kidney disease (ESKD). However, reduction in GFR in the general population is due to kidney or systemic disease. Retrospective studies comparing donors with matched general population controls have found no increased donor risk. Prospective studies comparing donors with controls (maximum follow-up, 9 years) have reported that donor GFR is stable or increases slightly, whereas GFR decreases in controls. However, these same studies identified metabolic and vascular donor abnormalities. There are a few retrospective studies comparing donors with controls. Each has limitations in selection of the control group, statistical analyses, and/or length of follow-up. One such study reported increased donor mortality; 2 reported a small increase in absolute risk of ESKD. Risk factors for donor ESKD are similar to those in the general population. Postdonation pregnancies are also associated with increased risk of hypertension and preeclampsia. There is a critical need for long-term follow-up studies comparing donors with controls from the same era, geographic area, and socioeconomic status who are healthy, with normal renal function on the date matching the date of donation, and are matched on demographic characteristics with the donors. These data are needed to optimize donor candidate counseling and informed consent.

Temporal trends in living kidney donation in France between 2007 and 2017

BACKGROUND

Long-term studies have demonstrated a slight increased risk for end-stage renal disease (ESRD) for living kidney donors (LKD). In France, living kidney donation doubled within the past 10 years. We investigated the change in characteristics of LKD between 2007 and 2017 and the adequacy of follow-up.

METHODS

Data were obtained from the national registry for LKD. We compared characteristics of LKD between two study periods: 2007-11 and 2012-17, and stratified donors by age and relation to recipient. We aggregated four characteristics associated with higher ESRD risk [young age, first-degree relation to recipient, obesity, low glomerular filtration rate (GFR) for age] in a single risk indicator ranging from 0 to 4.

RESULTS

We included 3483 donors. The proportion of unrelated donors >56 years of age increased significantly. The proportion of related donors <56 years of age decreased significantly. The body mass index and proportion of obese donors did not change significantly. The proportion of donors with low estimated GFR for age decreased significantly from 5% to 2.2% (P < 0.001). The proportion of donors with adequate follow-up after donation increased from 19.6% to 42.5% (P < 0.001). No donor had a risk indicator equal to 4, and the proportion of donors with a risk indicator equal to 0 increased significantly from 19.2% to 24.9% (P < 0.001).

CONCLUSIONS

An increase in living kidney donation in France does not seem to be associated with the selection of donors at higher risk of ESRD and the proportion of donors with adequate annual follow-up significantly increased.

Have we reached the limits in altruistic kidney donation?

Altruistic donation (unspecified donation) is an important aspect of living donor kidney transplantation. Although donation to a stranger is lawful and supported in many countries, it remains uncommon and not actively promoted. Herein, we ask the question if we have reached the limit in altruistic donation. In doing so, we examine important ethical questions that define the limits of unspecified donation, such as the appropriate balance between autonomous decision-making and paternalistic protection of the donor, the extent of outcome uncertainty and risk-benefit analyses that donors should be allowed to accept. We also consider the scrutiny and acceptance of donor motives, the potential for commercialization, donation to particular categories of recipients (including those encountered through social media) and the ethical boundaries of active promotion of unspecified kidney donation. We conclude that there is scope to increase the number of living donation kidney transplants further by optimizing existing practices to support and promote unspecified donation. A number of strategies including optimization of the assessment process, innovative approaches to reach potential donors together with reimbursement of expenses and a more specific recognition of unspecified donation are likely to lead to a meaningful increase in this type of donation.

Five decades with grandparent donors: The Norwegian strategy and experience

Living donors (LDs) are preferred over DDs for renal transplantation in children due to superior GS. Oslo University Hospital has never restricted living donation by upper age. The aim of this study was to investigate long-term outcomes using grandparents (GPLD) compared to PLD. Retrospective nationwide review in the period 1970-2017. First renal graft recipients using a GPLD were compared to PLD kidney recipients for long-term renal function and GS. 278 children (≤18 years) received a first renal transplant: 27/251 recipients with a GPLD/PLD. GPLD (median 59 (42-74) years) were significantly older than PLD (median 41 (23-65) years, (P < .001). Median DRAD was 52 (38-70) vs 28 (17-48) years, respectively. GS from GPLD and PLD had a 1-, 5-, and 10-year survival of 100%, 100%, and 90% vs 93%, 82%, and 72%, respectively (P = .6). In a multivariate Cox regression analysis adjusted for gender, donor age, recipient age, and year of transplant, this finding was similar (HR 0.98; 95% CI 0.34-2.84, P = .97). Five-year eGFR was 47.3 and 59.5 mL/min/1.73 m2 in the GPLD and PLD groups (P = .028), respectively. In this nationwide retrospective analysis, GS for pediatric renal recipients using GPLD was comparable to PLD. Renal function assessed as eGFR was lower in the GPLD group. The GPLD group was significantly older than the PLD group, but overall this did not impact transplant outcome. Based on these findings, older age alone should not exclude grandparent donations.

KDOQI US Commentary on the 2017 KDIGO Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors

Living kidney donation is widely practiced throughout the world. During the past 2 decades, various groups have provided guidance about the evaluation and care of living donors. However, during this time, our knowledge in the field has advanced substantially and many agreed on the need for a comprehensive, unifying document. KDIGO (Kidney Disease: Improving Global Outcomes) addressed this issue at an international level with the publication of its clinical practice guideline on the evaluation and care of living kidney donors. The KDIGO work group extensively reviewed the available literature and wrote a series of guideline recommendations using various degrees of evidence when available. As has become recent practice, NKF-KDOQI (National Kidney Foundation-Kidney Disease Outcomes Quality Initiative) convened a work group to provide a commentary on the KDIGO guideline, with a focus on how these recommendations apply in the context of the United States. In the United States, the United Network for Organ Sharing (UNOS) guides and regulates the practice of living kidney donation. While the KDIGO guideline for the care of living kidney donors and UNOS policy are similar in most aspects of the care of living kidney donors, several important areas are not consistent or do not align with common practice by US transplantation programs in areas in which UNOS has not set specific policy. For the time being, and recognizing the value of the KDIGO guidelines, US transplantation programs should continue to follow UNOS policy.

Kidney Donation Withdrawal and Related Factors Among the Potential Donors of Living Kidney Transplant

BACKGROUND

This study aimed to discuss the reasons for kidney donation withdrawal and related factors among the potential donors of living kidney transplant.

METHODS

This study was conducted in outpatient departments with purposive sampling. Potential donors received relevant examinations and completed questionnaires when they would donate their kidneys for living related kidney transplant. Researchers tracked the final decision of potential donors. The structured questionnaire included basic data, psychosocial adjustment to illness scale, and decisional conflict scale.

RESULTS

A total of 53 potential donors participated in this study, 46 of whom completed the kidney donation surgery (86.6%). The factors related to the final decision of kidney donation or kidney donation withdrawal included self-ranking health condition, value clarity, feeling supported in decision making, and overall decisional conflict.

CONCLUSION

Organ transplant teams should conduct a complete physical and psychological assessment of potential donors, provide information and support, and assist potential donors to clarify their true values and willingness to undergo kidney donation. Thus, each potential donor can decide to donate in true accordance with their willingness.

The changing landscape of live kidney donation in the United States from 2005 to 2017

The number of live kidney donors has declined since 2005. This decline parallels the evolving knowledge of risk for biologically related, black, and younger donors. To responsibly promote donation, we sought to identify declining low-risk donor subgroups that might serve as targets for future interventions. We analyzed a national registry of 77 427 donors and quantified the change in number of donors per 5-year increment from 2005 to 2017 using Poisson regression stratified by donor-recipient relationship and race/ethnicity. Among related donors aged <35, 35 to 49, and ≥50 years, white donors declined by 21%, 29%, and 3%; black donors declined by 30%, 31%, and 12%; Hispanic donors aged <35 and 35 to 49 years declined by 18% and 15%, and those aged ≥50 increased by 10%. Conversely, among unrelated donors aged <35, 35 to 49, and ≥50 years, white donors increased by 12%, 4%, and 24%; black donors aged <35 and 35 to 49 years did not change but those aged ≥50 years increased by 34%; Hispanic donors increased by 16%, 21%, and 46%. Unlike unrelated donors, related donors were less likely to donate in recent years across race/ethnicity. Although this decline might be understandable for related younger donors, it is less understandable for lower-risk related older donors (≥50 years). Biologically related older individuals are potential targets for interventions to promote donation.

"You can't get there from here": Critical obstacles to current estimates of the ESRD risks of young living kidney donors

Short studies that generate lifetime end-stage renal disease (ESRD) risks for young living kidney donors have conflicted with the knowledge and practice of nontransplant specialists. A widely accepted online risk calculator (OLRC) is no exception. It uses 6.4 year observations and an ostensibly empiric methodology to predict low lifetime risks for normal young candidates. But the nonspecific ESRD risk factors identified in this study are likely features of kidney diseases that were already underway at study entry. No practicing nephrologist would use their absence to predict any specific kidney disease that had yet to begin, which is essential for excluding high-risk individuals. The OLRC's risk estimates are particularly low because it also does not assign to young adults about 70% of the lifetime ESRD that they will experience as they age, which is part of their risk. It reinforces traditional concepts of low donor risk, minimizing the potential relevance of recent, sometimes concerning, long-term outcome data. These data suggest many similarities between postdonation ESRD and ESRD in the general population, about which much is already known. Despite our best efforts, the heterogeneity and exponential accumulation of end-stage kidney diseases over time prevent long-term predictions of risk for young kidney donors.

Renal functional reserve capacity before and after living kidney donation

Compensatory gomerular filtration rate (GFR) increase after kidney donation results in a GFR above 50% of the predonation value. The renal functional reserve (RFR) assessed by the renal response to dopamine infusion (RFRdopa) is considered to reflect functional reserve capacity and is thought to be a tool for living donor screening. However, it is unknown if the RFRdopa predicts long-term kidney function. Between 1984 and 2017, we prospectively measured GFR (125I-iothalamate) and RFR by dopamine infusion in 937 living kidney donors. We performed linear regression analysis of predonation RFRdopa and postdonation GFR. In donors with 5-yr follow-up after donation we assessed the association with long-term GFR. Mean donor age was 52  yr (SD 11); 52% were female. Mean predonation GFR was 114  ml/min (SD 22), GFRdopa was 124 ml/min (SD 24), resulting in an RFR of 9 ml/min (SD 10). Three months postdonation, GFR was 72 ml/min (SD 15) and GFRdopa was 75 ml/min (SD 15), indicating that donors still had RFRdopa [3 ml/min (SD 6), P < 0.001]. Predonation RFRdopa was not associated with predonation GFR [standardized (st.) β −0.009, P = 0.77] but was positively associated with GFR 3 mo after donation (st. β 0.12, P < 0.001). In the subgroup of donors with 5-yr follow-up data ( n = 383), RFRdopa was not associated with GFR at 5 yr postdonation (st. β 0.05, P = 0.35). In conclusion, RFRdopa is a predictor of short-term GFR after living kidney donation but not of long-term kidney function. Therefore, measurement of the RFRdopa is not a useful tool for donor screening. Studies investigating long-term renal adaptation are warranted to study the effects of living kidney donation and improve donor screening.

Causes and timing of end-stage renal disease after living kidney donation

End-stage renal disease (ESRD) is a risk after kidney donation. We sought, in a large cohort of kidney donors, to determine the causes of donor ESRD, the interval from donation to ESRD, the role of the donor/recipient relationship, and the trajectory of the estimated GFR (eGFR) from donation to ESRD. From 1/1/1963 thru 12/31/2015, 4030 individuals underwent living donor nephrectomy at our center, as well as ascertainment of ESRD status. Of these, 39 developed ESRD (mean age ± standard deviation [SD] at ESRD, 62.4 ± 14.1 years; mean interval between donation and ESRD, 27.1 ± 9.8 years). Donors developing ESRD were more likely to be male, as well as smokers, and younger at donation, and to have donated to a first-degree relative. Of donors with a known cause of ESRD (n = 25), 48% was due to diabetes and/or hypertension; only 2 from a disease that would have affected 1 kidney (cancer). Of those 25 with an ascertainable ESRD cause, 4 shared a similar etiology of ESRD with their recipient. Almost universally, thechange of eGFR over time was stable, until new-onset disease (kidney or systemic). Knowledge of factors contributing to ESRD after living kidney donation can improve donor selection and counseling, as well as long-term postdonation care.

Risk of ESRD in prior living kidney donors

We studied End-Stage Renal Disease (ESRD) in living kidney donors (LKDs) who donated in the United States between 1994 and 2016 (n = 123 526), using Organ Procurement and Transplantation Network and Centers for Medicare and Medicaid Services data. Two hundred eighteen LKDs developed ESRD, with a median of 11.1 years between donation and ESRD. Absolute 20-year risk was low but not uniform, with risk associated with race, age, and sex and increasing exponentially over time. LKDs had increased risk of ESRD if they were male (adjusted hazard ratio [aHR]: 1.75, 95% confidence interval [95%CI]: 1.33-2.31), had higher BMI (aHR: 1.34 per 5 kg/m² , 95%CI: 1.10-1.64) or lower estimated GFR (aHR: 0.89 per 10 mL/min, 95% CI: 0.80-0.99), were first-degree relatives of the recipient (parent: [aHR: 2.01, 95% CI: 1.26-3.21]; full sibling [aHR: 1.87, 95%CI: 1.23-2.84]; identical twin [aHR: 19.79, 95%CI: 7.65-51.24]), or lived in lower socioeconomic status neighborhoods at donation (aHR: 0.87 per $10k increase; 95%CI: 0.77-0.99). We found a significant interaction between donation age and race, with higher risk at older ages for white LKDs (aHR: 1.26 per decade, 95%CI: 1.04-1.54), but higher risk at younger ages for black LKDs (aHR: 0.75 per decade, 95%CI: 0.57-0.99). These findings further inform risk assessment of potential LKDs.

Long-term risks of kidney living donation: review and position paper by the ERA-EDTA DESCARTES working group

Two recent matched cohort studies from the USA and Norway published in 2014 have raised some concerns related to the long-term safety of kidney living donation. Further studies on the long-term risks of living donation have since been published. In this position paper, Developing Education Science and Care for Renal Transplantation in European States (DESCARTES) board members critically review the literature in an effort to summarize the current knowledge concerning long-term risks of kidney living donation to help physicians for decision-making purposes and for providing information to the prospective live donors. Long-term risk of end-stage renal disease (ESRD) can be partially foreseen by trying to identify donors at risk of developing ‘de novo’ kidney diseases during life post-donation and by predicting lifetime ESRD risk. However, lifetime risk may be difficult to assess in young donors, especially in those having first-degree relatives with ESRD. The study from Norway also found an increased risk of death after living donor nephrectomy, which became visible only after >15 years of post-donation follow-up. However, these findings are likely to be largely the result of an overestimation due to the confounding effect related to a family history of renal disease. DESCARTES board members emphasize the importance of optimal risk–benefit assessment and proper information to the prospective donor, which should also include recommendations on health-promoting behaviour post-donation.

Ambulatory blood pressure monitoring in living kidney donors: What changes in 10 years?

In renal transplantation, living donations have more significant benefits compared to cadaveric donations. However, a probable increase in blood pressure following donation should also be kept in mind. In this study, we investigated the long-term changes in blood pressure in living kidney donors using ambulatory blood pressure monitoring and we explored the e-GFR and albuminuria/proteinuria measurements at 3 time points. Twenty-eight living kidney donors and 39 healthy individuals were evaluated and compared at the baseline and later at the 10th year. At the 10th year, creatinine levels were higher and eGFR levels were lower in the donors, whereas the systolic and diastolic measurements of the donors and controls and the prevalence of nondipping in the donors and controls were similar. Our study may be underpowered due to its small population size. However, our results at the 10th year follow-up indicated that the risk of hypertension might not seem to have increased in the well-selected donors. In addition, the majority of our donors had preserved their GFR values. Therefore, we can suggest that living kidney donation appears to be safe in well-selected patients over a 10-year time frame.

GFR ≤25 years postdonation in living kidney donors with (vs. without) a first-degree relative with ESRD

An increased risk of ESRD has been reported for living kidney donors, and appears to be higher for those donating to a relative. The reasons for this are not clear. One possibility is that ESRD is due to the nephrectomy-related reduction in GFR, followed by an age-related decline that may be more rapid in related donors. Between 1/1/1990 and 12/31/2014, we did 2002 living donor nephrectomies. We compared long-term postdonation eGFR trajectory for donors with (n = 1245) vs. without (n = 757) a first-degree relative with ESRD. Linear mixed-effects models were used to model the longitudinal trajectory of eGFR. With all other variables held constant, we noted a steady average increase in eGFR until donors reached age 70: 1.12 (95% CI: 0.92-1.32) mL/min/1.73m^² /yr between 6 weeks and 5 years postdonation; 0.24 (0.00-0.49) mL/min/1.73m^² /yr between 5 and 10 years; and 0.07 (-0.10 to +0.25) mL/min/1.73m^² /yr between 10 and 20 years for donors with attained age less than 70. After age 70, eGFR declined. After we adjusted for predonation factors, the difference in eGFR slopes between related and unrelated donors was 0.20 mL/min/1.753 m² /year (0.07-0.33). Our data suggests that postdonation, kidney donor eGFR increases each year for a number of years and that eGFR trajectory does not explain any increase in ESRD after donation.

Patterns of End-Stage Renal Disease Caused by Diabetes, Hypertension, and Glomerulonephritis in Live Kidney Donors

Inferences about late risk of end-stage renal disease (ESRD) in live kidney donors have been extrapolated from studies averaging <10 years of follow-up. Because early (<10 years) and late (≥10 years) postdonation ESRD may differ by causal mechanism, it is possible that extrapolations are misleading. To better understand postdonation ESRD, we studied patterns of common etiologies including diabetes, hypertension and glomerulonephritis (GN; as reported by providers) using donor registry data linked to ESRD registry data. Overall, 125 427 donors were observed for a median of 11.0 years (interquartile range 5.3-15.7 years; maximum 25 years). The cumulative incidence of ESRD increased from 10 events per 10 000 at 10 years after donation to 85 events per 10 000 at 25 years after donation (late vs. early ESRD, adjusted for age, race and sex: incidence rate ratio [IRR] _1.3 1.7_2.3 [subscripts are 95% confidence intervals]). Early postdonation ESRD was predominantly reported as GN-ESRD; however, late postdonation ESRD was more frequently reported as diabetic ESRD and hypertensive ESRD (IRR _2.3 7.7_25.2 and _1.4 2.6_4.6 , respectively). These time-dependent patterns were not seen with GN-ESRD (IRR _0.4 0.7_1.2 ). Because ESRD in live kidney donors has traditionally been reported in studies averaging <10 years of follow-up, our findings suggest caution in extrapolating such results over much longer intervals.