Donors at risk: impaired glucose tolerance

Living Donation and Pregnancy-Related Complications: State of the Evidence and Call To Action for Improved Risk Assessment

Living kidney donation and living liver donation significantly increases organ supply to make lifesaving transplants possible, offering survival benefits to the recipients and cost savings to society. Of all living donors, 40% are women of childbearing age. However, limited data exist regarding the effect of donation on future pregnancies and of pregnancy-related complications on postdonation outcomes. In February 2023, the American Society of Transplantation Women's Health Community of Practice held a virtual Controversies Conference on reproductive health, contraception, and pregnancy after transplantation and living donation. Experts in the field presented the available data. Smaller breakout sessions were created to discuss findings, identify knowledge gaps, and develop recommendations. We present the conference findings related to living donation. The evidence reviewed shows that gestational hypertension and gestational diabetes mellitus before kidney donation have been associated with an increased risk of developing postdonation hypertension and diabetes mellitus, respectively, without increasing the risk of developing an eGFR <45 ml/min after donation. The risk of preeclampsia in living kidney donors increases to 4%-10%, and low-dose aspirin may help reduce that risk. Little is known about the financial burden for living donors who become pregnant, their risk of postpartum depression, or the optimal time between donation and conception. The data on living liver donors are even scarcer. The creation of a registry of donor candidates may help answer many of these questions and, in turn, educate prospective donors so that they can make an informed choice.

Respecting living kidney donor autonomy: an argument for liberalising living kidney donor acceptance criteria

Doctors routinely refuse donation offers from prospective living kidney donors with certain comorbidities such as diabetes or obesity out of concern for donor wellbeing. This refusal occurs despite the ongoing shortage of kidney transplants and the superior performance of living donor kidney transplants compared to those from deceased donors. In this paper, we argue that this paternalistic refusal by doctors is unjustified and that, within limits, there should be greater acceptance of such donations. We begin by describing possible weak and strong paternalistic justifications of current conservative donor acceptance guidelines and practices. We then justify our position by outlining the frequently under-recognised benefits and the routinely overestimated harms of such donation, before discussing the need to respect the autonomy of willing donors with certain comorbidities. Finally, we respond to a number of possible objections to our proposal for more liberal kidney donor acceptance criteria. We use the situation in Australia as our case study, but our argument is applicable to comparable situations around the world.

Pre-kidney Donation Pregnancy Complications and Long-term Outcomes

BACKGROUND

Hypertension and diabetes are contraindications for living kidney donation in young candidates. However, little is known about the long-term outcomes of women who had these pregnancy-related complications and subsequently became donors. In the general population, gestational hypertension (GHtn), preeclampsia/eclampsia, and gestational diabetes (GDM) are associated with long-term risks.

METHODS

Donors with the specified predonation complication were matched to contemporary control donors with pregnancies without the complication using nearest neighbor propensity score matching. Propensity scores were estimated using logistic regression with covariates for gravidity, blood pressure, glucose, body mass index, age, and creatinine at donation, donation year, race, relationship with recipient, and family history of disease. Long-term incidence of hypertension, diabetes, cardiovascular disease, and reduced renal function (estimated glomerular filtration rate [eGFR] <30, eGFR <45 mL/min/1.73 m 2 ) were compared between groups using proportional hazards models.

RESULTS

Of 1862 donors with predonation pregnancies, 48 had preeclampsia/eclampsia, 49 had GHtn without preeclampsia, and 43 had GDM. Donors had a long interval between first pregnancy and donation (median, 18.5 y; interquartile range, 10.6-27.5) and a long postdonation follow-up time (median, 18.0; interquartile range, 9.2-27.7 y). GHtn was associated with the development of hypertension (hazard ratio, 1.89; 95% confidence interval, 1.26-2.83); GDM was associated with diabetes (hazard ratio, 3.04; 95% confidence interval, 1.33-6.99). Pregnancy complications were not associated with eGFR <30 or eGFR <45 mL/min/1.73 m 2 .

CONCLUSIONS

Our data suggest that women with predonation pregnancy-related complications have long-term risks even with a normal donor evaluation. Donor candidates with a history of pregnancy-related complications should be counseled about these risks.

Critical Appraisal of International Clinical Practice Guidelines in Kidney Transplantation Using the Appraisal of Guidelines for Research and Education II Tool: A Systematic Review

BACKGROUND

Although clinical practice guidelines (CPGs) are used for the development of local protocols in kidney transplantation (Ktx), the quality of their methodology is variable. This systematic review aimed to critically appraise international CPGs in all aspects of Ktx using the Appraisal of Guidelines for Research and Evaluation II tool.

METHODS

Clinical Practice Guidelines in Ktx and donation published between 2010 and 2017 were identified from MEDLINE, Embase, National Guideline Clearinghouse, National Health Service and National Institute for Health and Care Excellence Evidence Searches, and the websites of transplant societies. Using Appraisal of Guidelines for Research and Evaluation II, 3 appraisers assessed the quality of CPGs. Interrater reliability was measured using the intraclass correlation coefficient (ICC).

RESULTS

Searches identified 3168 records, and 115 CPGs were included. The highest scoring Appraisal of Guidelines for Research and Evaluation II domain was "scope and purpose" (80%; range, 30%-100%), followed by "clarity of presentation" (77%; range, 43%-98%), "editorial independence" (52%; range, 0%-94%), "rigor of development" (47%; range 6%-97%) and "stakeholder involvement" (41%; range, 11%-85%). The poorest scoring domain was "applicability" (31%; range, 3%-74%). Most CPGs were recommended for future use either with (63%) or without (18%) modifications. A small number (14%) were not recommended for future use or reviewers (5%) did not agree on recommending the CPG. The overall mean CPG quality score was 4 of 7 (range, 2-7). The mean ICC of 0.74 indicated substantial agreement between reviewers.

CONCLUSIONS

The quality of international CPGs in Ktx was variable, and most CPGs lacked key aspects of methodological robustness and transparency. Improvements in methodology, patient involvement, and strategies for implementation are required.

Optimizing Live Kidney Donor Workup: A Decision Analysis Approach

BACKGROUND

Screening potential live kidney donors is an intense process for both candidates and the healthcare system. It is conventionally implemented using a standard generic protocol. Efficiencies in this process could potentially be achieved using personalized protocols that are optimized for a given candidate. Aim: To create personalized protocols (by age, sex, and paired exchange status) and evaluate them relative to the standard generic protocol.

METHODS

Two personalized protocols were created. One sequenced tests according to probability (high to low) of excluding a given candidate. The other sequenced tests according to the expected cost (low to high) per exclusion. Test costs and exclusion probabilities were extracted predominantly from Australian sources. These were integrated into a decision analysis incorporating Markov processes. This estimated the expected financial cost and expected number of tests performed to exclude an ineligible candidate in the standard generic and personalized protocols.

RESULTS

The standard generic protocol consistently ranked poorest in terms of expected costs and expected tests per exclusion across all ages, sexes, and paired exchange status. Compared with the most efficient personalized protocol, the standard generic protocol was on average A$1767.49 more expensive and required 3.53 more tests.

CONCLUSIONS

Personalized protocols enhance the ability of a kidney transplant unit to effectively exclude live kidney donor candidates more quickly and cost effectively compared with the conventional standard generic protocol.

Impact of screening for metabolic syndrome on the evaluation of obese living kidney donors

BACKGROUND

We report our experience with metabolic syndrome screening for obese living kidney donor candidates to mitigate the long-term risk of CKD.

METHODS

We retrospectively reviewed 814 obese (BMI≥30) and 993 nonobese living kidney donor evaluations over 12 years. Using logistic regression, we explored interactions between social/clinical variables and candidate acceptance before and after policy implementation.

RESULTS

Obese donor candidate acceptance decreased after metabolic syndrome screening began (56.3%, 46.3%, p < 0.01), while nonobese candidate acceptance remained similar (59.6%, 59.2%, p = 0.59). Adjusting for age, gender, race, BMI, and number of prior evaluations, acceptance of obese candidates decreased significantly more than nonobese (p = 0.025). In candidates without metabolic syndrome, there was no significant change in how age, sex, race, or BMI affected a donor candidate's probability of acceptance.

CONCLUSION

Metabolic syndrome screening is a simple stratification tool for centers with liberal absolute BMI cut-offs to exclude potentially higher-risk obese candidates.

Diabetes Mellitus in Living Pancreas Donors: Use of Integrated National Registry and Pharmacy Claims Data to Characterize Donation-Related Health Outcomes

BACKGROUND

Living donor pancreas transplant is a potential treatment for diabetic patients with end-organ complications. Although early surgical risks of donation have been reported, long-term medical outcomes in living pancreas donors are not known.

METHODS

We integrated national Scientific Registry of Transplant Recipients data (1987-2015) with records from a nationwide pharmacy claims warehouse (2005-2015) to examine prescriptions for diabetes medications and supplies as a measure of postdonation diabetes mellitus. To compare outcomes in controls with baseline good health, we matched living pancreas donors to living kidney donors (1:3) by demographic traits and year of donation.

RESULTS

Among 73 pancreas donors in the study period, 45 were identified in the pharmacy database: 62% women, 84% white, and 80% relatives of the recipient. Over a mean postdonation follow-up period of 16.3 years, 26.7% of pancreas donors filled prescriptions for diabetes treatments, compared with 5.9% of kidney donors (odds ratio, 4.13; 95% confidence interval, 1.91-8.93; P = 0.0003). Use of insulin (11.1% vs 0%) and oral agents (20.0% vs 5.9%; odds ratio, 4.50, 95% confidence interval, 2.09-9.68; P = 0.0001) was also higher in pancreas donors.

CONCLUSIONS

Diabetes is more common after living pancreas donation than after living kidney donation, supporting clinical consequences from reduced endocrine reserve.

KDIGO Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors

The 2017 Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors is intended to assist medical professionals who evaluate living kidney donor candidates and provide care before, during and after donation. The guideline development process followed the Grades of Recommendation Assessment, Development, and Evaluation (GRADE) approach and guideline recommendations are based on systematic reviews of relevant studies that included critical appraisal of the quality of the evidence and the strength of recommendations. However, many recommendations, for which there was no evidence or no systematic search for evidence was undertaken by the Evidence Review Team, were issued as ungraded expert opinion recommendations. The guideline work group concluded that a comprehensive approach to risk assessment should replace decisions based on assessments of single risk factors in isolation. Original data analyses were undertaken to produce a "proof-in-concept" risk-prediction model for kidney failure to support a framework for quantitative risk assessment in the donor candidate evaluation and defensible shared decision making. This framework is grounded in the simultaneous consideration of each candidate's profile of demographic and health characteristics. The processes and framework for the donor candidate evaluation are presented, along with recommendations for optimal care before, during, and after donation. Limitations of the evidence are discussed, especially regarding the lack of definitive prospective studies and clinical outcome trials. Suggestions for future research, including the need for continued refinement of long-term risk prediction and novel approaches to estimating donation-attributable risks, are also provided.In citing this document, the following format should be used: Kidney Disease: Improving Global Outcomes (KDIGO) Living Kidney Donor Work Group. KDIGO Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors. Transplantation. 2017;101(Suppl 8S):S1-S109.

Risk-Factor Profile of Living Kidney Donors: The Australia and New Zealand Dialysis and Transplant Living Kidney Donor Registry 2004-2012

BACKGROUND

Recent literature suggests that living kidney donation may be associated with an excess risk of end-stage kidney disease and death. Efforts to maximize access to transplantation may result in acceptance of donors who do not fit within current guidelines, potentially placing them at risk of adverse long-term outcomes.

METHODS

We studied the risk profile of Australian and New Zealand living kidney donors using data from the Australia and New Zealand Dialysis and Transplant Living Kidney Donor Registry over 2004 to 2012. We compared their predonation profile against national guidelines for donor acceptance.

RESULTS

The analysis included 2,932 donors (mean age 48.8 ± 11.2 years, range 18-81), 58% female and 87% Caucasian. Forty (1%) had measured glomerular filtration rate less than 80 mL/min; 32 (1%) had proteinuria >300 mg/day; 589 (20%) were hypertensive; 495 (18%) obese; 9 (0.3%) were diabetic while a further 55 (2%) had impaired glucose tolerance; and 218 (7%) were current smokers. Overall 767 donors (26%) had at least one relative contraindication to donation and 268 (9%) had at least one absolute contraindication according to national guidelines.

CONCLUSIONS

Divergence of current clinical practice from national guidelines has occurred. In the context of recent evidence demonstrating elevated long-term donor risk, rigorous follow-up and reporting of outcomes are now mandated to ensure safety and document any change in risk associated with such a divergence.

Development of a Donor-Centered Approach to Risk Assessment: Rebalancing Nonmaleficence and Autonomy

Living kidney donors are often excluded from the shared decision making and patient-centered models that are advocated in medical practice. Thresholds for acceptable risk vary between transplant centers, and between clinicians and donors. Although donor selection committees commonly focus on medical risks, potential donors also consider nonmedical risks and burdens, which may alter their assessment of an acceptable level of medical risk. Thus, transplant centers may encounter ethical tensions between nonmaleficence and respect for donor autonomy. A donor-centered model of risk assessment and risk reconciliation would integrate the donor's values and preferences in a shared decision about their eligibility to donate. This paper argues for shifting to a donor-centered model of risk assessment, and presents a research agenda to facilitate the greater participation of donors in their own evaluation and approval processes.

Living kidney donation: outcomes, ethics, and uncertainty

Since the first living-donor kidney transplantation in 1954, more than half a million living kidney donations have occurred and research has advanced knowledge about long-term donor outcomes. Donors in developed countries have a similar life expectancy and quality of life as healthy non-donors. Living kidney donation is associated with an increased risk of end-stage renal disease, although this outcome is uncommon (<0·5% increase in incidence at 15 years). Kidney donation seems to elevate the risks of gestational hypertension and pre-eclampsia. Many donors incur financial expenses due to factors such as lost wages, need for sick days, and travel expenses. Yet, most donors have no regrets about donation. Living kidney donation is practised ethically when informed consent incorporates information about risks, uncertainty about outcomes is acknowledged when it exists, and a donor's risks are proportional to benefits for the donor and recipient. Future research should determine whether outcomes are similar for donors from developing countries and donors with pre-existing conditions such as obesity.

Long term prospective assessment of living kidney donors: single center experience

Virtually, all studies reporting the outcomes of living kidney donation beyond the first year from donation were retrospective. In this prospective study, the outcome of 81 consecutive living kidney donors was thoroughly evaluated. Clinical, laboratory, and radiological assessments were carried out at predonation (basal), 3, 6, 12, and 24 months after donation. The mean age at time of donation was 37.8 ± 9.8 years and the majority was females (75.3%). The mean BMI increased significantly after donation (P < 0.04). The mean serum creatinine levels (mg/dl) were 0.75 ± 0.14, 1.01 ± 0.22, 0.99 ± 0.21, 0.98 ± 0.20, and 0.94 ± 0.20 (P < 0.0001). Likewise, the mean levels of measured creatinine clearance (mL/min) were 148.8 ± 35.7, 94.7 ± 26.6, 95.5 ± 24.6, 96.7 ± 20.2, and 101.6 ± 26.2 (P < 0.0001). The mean 24 hours urinary protein excretion (gm/dL) were 0.09 ± 0.03, 0.19 ± 0.18, 0.16 ± 0.09, 0.18 ± 0.25, and 0.17 ± 0.12 (P < 0.0001). There were significant increases in the means of the longitudinal and transverse diameters of the remaining kidney over time (P < 0.001). Out of 42 female donors, eleven female donors have got successful postdonation pregnancies. There were no reported surgical complications, either intra- or postoperative. Long-term follow-up is necessary for all living kidney donors through local institutional and world registries. This trial is registered with ClinicalTrials.gov NCT00813579.

Ethical issues relating to renal transplantation from prediabetic living donor

Background

In Mexico, diabetes mellitus is the main cause of end − stage kidney disease, and some patients may be transplant candidates. Organ supply is limited because of cultural issues. And, there is a lack of standardized clinical guidelines regarding organ donation. These issues highlight the tension surrounding the fact that living donors are being selected despite being prediabetic. This article presents, examines and discusses using the principles of non-maleficience, autonomy, justice and the constitutionally guaranteed right to health, the ethical considerations that arise from considering a prediabetic person as a potential kidney donor.

Discussion

Diabetes is an absolute contraindication for donating a kidney. However, the transplant protocols most frequently used in Mexico do not consider prediabetes as exclusion criteria. In prediabetic persons there are well known metabolic alterations that may compromise the long − term outcomes of the transplant if such donors are accepted. Even so, many of them are finally included because there are not enough donor candidates. Both, families and hospitals face the need to rapidly accept prediabetic donors before the clinical conditions of the recipient and the evolution of the disease exclude him/her as a transplant candidate; however, when using a kidney potentially damaged by prediabetes, neither the donor’s nor the recipient’s long term health is usually considered.

Considering the ethical implication as well as the clinical and epidemiological evidence, we conclude that prediabetic persons are not suitable candidates for kidney donation. This recommendation should be taken into consideration by Mexican health institutions who should rewrite their transplant protocols.

Summary

We argue that the decision to use a kidney from a living donor known to be pre-diabetic or from those persons with family history of T2DM, obesity, hypertension, or renal failure, should be considered unethical in Mexico if the donor bases the decision to donate on socially acceptable norms rather than informed consent as understood in modern medicine.