Acceptability of older adults as living kidney donors

Medical Suitability and Willingness for Living Kidney Donation Among Older Adults

RATIONALE & OBJECTIVE

The benefits of kidney transplantation compared with treatment with dialysis, including in older adults, are primarily limited by the number of donated kidneys. We studied the potential to expand the use of older living kidney donors.

STUDY DESIGN

Secondary analysis of the Berlin Initiative Study, a population-based cohort.

SETTING & PARTICIPANTS

2,069 adults aged≥70 years in Germany.

EXPOSURE

Age and sex.

OUTCOME

Suitability for living donation assessed by the absence of kidney-related exclusions for donation including albuminuria and low estimated glomerular filtration rate (eGFR) as well as absence of other medical exclusions. Willingness for living and deceased kidney donation assessed by participant survey.

ANALYTICAL APPROACH

Descriptive analysis.

RESULTS

Among the 2,069 participants (median age 80 years, 53% women, median eGFR 63mL/min/1.73m2), 93% had≥1 medical contraindication for living donation at study entry unrelated to eGFR or albuminuria. Using 2 published eGFR and albuminuria thresholds for donor acceptance, 38% to 54% of participants had kidney-related exclusions for donation. Among the 5% to 6% of participants with neither medical nor kidney-related exclusions for living donation at baseline, 11% to 12% remained suitable for donation during 8 years of follow-up. Willingness for living or deceased donation was high (73% and 60%, respectively).

LIMITATIONS

GFR was not measured, and medical exclusions unrelated to eGFR and albuminuria were assessed using a cohort database complemented by claims data.

CONCLUSIONS

One in 20 older adults were potentially suitable for living kidney donation, and willingness for living donation was high. Further studies are warranted to define the feasibility of expanding living kidney donation among older adults.

PLAIN-LANGUAGE SUMMARY

Although potentially beneficial, kidney transplantation remains infrequent among older adults aged≥70 years with kidney failure. Study evaluated the potential to increase living kidney donation among older adults, including their medical suitability as well as willingness to donate. Among 2,069 community-dwelling older adults (median age 80 years), 5% to 6% had no exclusion to donation. Among these individuals, 11% to 12% remained suitable for donation during 8 years of follow-up. Most exclusions were not related to eGFR and albuminuria. Willingness to living donation was high (73%). These findings highlight the potential benefits from expanding the pool of transplantable kidneys through the use of living donation in older adults.

Donor-reported barriers to living kidney donor follow-up

BACKGROUND

Despite regulations mandating follow-up laboratory testing for living kidney donors, less than half of transplant centers are in compliance. We sought to understand barriers to follow-up testing from the donors' perspective.

METHODS

We surveyed our center's living kidney donors. Binary logistic regression was used to assess factors associated with follow-up testing completion.

RESULTS

Of 185 living kidney donors, 110 (59.4%) participated. Among them, 82 (74.5%) completed 6-month laboratory testing, 76 (69.1%) completed 12-month testing, 68 (61.8%) completed both, and 21 (19.0%) completed neither. Six-month testing completion was strongly associated with 12-month testing completion (OR 9.74, 95%CI: 2.23-42.50; p = .002). Those who disagreed with the statements, "Getting labs checked wasn't a priority for me," (OR for completing 6-month testing: 15.05, 95%CI: 3.70-61.18; p < .001; OR for completing 12-month testing: 5.85, 95%CI: 1.94-17.63; p = .002); and, "I forgot to get labs drawn [until I was reminded]" (OR for completing 6-month testing: 6.93, 95%CI: 1.59-30.08; p = .01; OR for completing 12-month testing: 6.55, 95%CI: 1.98-21.63; p = .002) were more likely to complete testing.

CONCLUSIONS

To our knowledge, this is the only study providing perspective on donor insights regarding the need for follow-up testing post donation. Interventions to influence living donor attitudes toward follow-up testing may improve follow-up.

Post-kidney donation glomerular filtration rate measurement and estimation

BACKGROUND

Long-term consequences associated with kidney donation are controversial. Pre- and post-donation glomerular filtration rates (GFRs) are determinants of renal and cardiovascular risk weighting. In Latin America, there is limited experience in evaluating kidney function using GFR measurement techniques in kidney donors. The MDRD 4-variable and CKD-EPI equations are considered reasonable options. The objective of this study was to evaluate the performance of the MDRD and CKD-EPI equations in post-nephrectomy GFR dynamics in kidney donors.

MATERIALS AND METHODS

A prospective cohort study with GFR measurement and estimation in 189 kidney donors who underwent nephrectomy between 2007 and 2016 at the Hospital Privado Universitario de Córdoba [Private University Hospital of Córdoba] in Córdoba, Argentina. GFRs were evaluated before and after nephrectomy by iothalamate clearance determined by HPLC and by the MDRD and CKD-EPI equations for estimating GFR. Two groups were formed for this study: Group 1 (n=107), with an evaluation time subsequent to GFR stabilization (3 months) of up to 5 years, and Group 2 (n=82), with an evaluation time of 5-10 years following donation. Measured GFR (mGFR) was assessed by iothalamate clearance determined by HPLC.

RESULTS

Renal compensation values were 61.9% (52.0%-71.1%) and 75.6% (64.9%-84.4%) for Group 1 (n=107) and Group 2 (n=82), respectively. MDRD underestimated the GFR in 3.2% (90ml/min/1.73m²) and 38.6% (60ml/min/1.73m²) compared to the mGFR, and CKD-EPI underestimated the GFR in 2.6% (90ml/min/1.73m²) and 13.8% (60ml/min/1.73m²). Diagnostic performance was evaluated with a ROC curve (mGFR<60ml/min/1.73m²) for MDRD (ABC=0.66; CI: 0.59-0.73; sensitivity: 98.7%; specificity: 63.3%) and for CKD-EPI (ABC=0.79 CI: 0.73-0.85; sensitivity: 96.9%; specificity: 76.4%. Estimated GFR (eGFR) showed poor performance for estimating the glomerular filtration rate in the post-nephrectomy follow-up of donors over 50 years of age.

CONCLUSIONS

Equations for estimating GFRs showed poor performance for long-term follow-up of post-nephrectomy GFRs. Measuring GFRs to determine kidney function is recommended in the screening and follow-up of some donors under the current selection criteria.

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.

Extended Criteria Donors in Living Kidney Transplantation Including Donor Age, Smoking, Hypertension and BMI

Purpose

An expansion of selection criteria for deceased organ transplantation already exists to manage the current donor shortage. Comparable evaluation of risk factors for living donors should be investigated to improve this issue.

Patients and Methods

Our retrospective single-centre study analysed 158 patients with living kidney transplants performed between February 2006 and June 2012. We investigated the influence of donor risk factors (RF) including body mass index over 30 kg/m², age >60 years, active nicotine abuse and arterial hypertension on postoperative kidney function with focus on the recipients. This was measured for long-term survival and glomerular filtration rate (GFR) in a 5-year follow-up.

Results

Overall, out of 158 living donors, 84 donors were identified to have no risk factors, whereas 74 donors had at least one risk factor. We noted a significant higher delayed graft function (p=0.042) in the first 7 days after transplantation, as well as lower GFR of recipients of allografts with risk factors in the first-year after transplantation. In our long-term results, there was no significant difference in the functional outcome (graft function, recipient and graft survival) between recipients receiving kidneys from donors with no and at least one risk factors. In the adjusted analysis of subgroups of different risk factors, recipients of donors with “age over 60 years” at time of transplantation had a decreased transplant survival (p=0.014).

Conclusion

Thus, a careful expansion for selection criteria for living donors with critical evaluation could be possible, but especially the age of the donors could be a limited risk factor.

Comparison of Graft Outcome Between Donation After Circulatory Death and Living-Donor Kidney Transplantation

BACKGROUND

Donation after cardiac death (DCD) and living-donor (LD) kidney transplantation are the main kidney transplantation types in China. But the outcome of DCD kidney transplantation compared with LD kidney transplantation remains unclear.

METHODS

In this study, 325 DCD and 409 LD kidney transplantations were included. We retrospectively compared 3-year graft survival, death-censored graft survival, recipient survival, and graft function. All kidneys of the DCD group were procured from voluntary donation after the citizens' death by the Organ Procurement Organization (OPO) in the presence of the Red Cross, and the transplantation application was approved by the Organ Transplant Ethics Committee.

RESULTS

The graft function at year 3 in the DCD group was superior to that of the LD group (eGFR: 71.14±22.28 vs 64.29±16.76 mL/min/1.73 m²; P < .001). After matching donor age, there was no significant difference between the paired DCD and LD group (eGFR: 62.22±18.50 vs 66.99±17.81 mL/min/1.73 m²; P = .068). The 3-year graft survival (94.7% vs 97.4%; P = .041) and recipient survival (97.2% vs 99.5%; P = .011) were a little worse in the total DCD group. However, once the DCD kidney transplantation recipients survived more than 2 months, graft and recipient survival rates were similar between the DCD and LD groups (97.7% vs 97.4%, P = .866 and 99.5% vs 99.0%, P = .466). These results were confirmed in an age-paired groups study. Severe infection was the main cause of graft loss and recipient death in the early stage of DCD transplantation.

CONCLUSIONS

Medium- and long-term graft function of DCD kidney transplantation were comparable to LD kidney transplantation. Our results supported the continued use of DCD kidneys.

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.

Risk of ESKD in Older Live Kidney Donors with Hypertension

BACKGROUND AND OBJECTIVES

Hypertension in older kidney donor candidates is viewed as safe. However, hypertension guidelines have evolved and long-term outcomes have not been explored. We sought to quantify the 15-year risk of ESKD and mortality in older donors (≥50 years old) with versus those without hypertension.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A United States cohort of 24,533 older donors from 1999 to 2016, including 2265 with predonation hypertension, were linked to Centers for Medicare and Medicaid Services data and the Social Security Death Master File to ascertain ESKD development and mortality. The exposure of interest was predonation hypertension. From 2004 to 2016, hypertension was defined as documented predonation use of antihypertensive therapy, regardless of systolic BP or diastolic BP; from 1999 to 2003, when there was no documentation of antihypertensive therapy, hypertension was defined as predonation systolic BP ≥140 or diastolic BP ≥90 mm Hg.

RESULTS

Older donors were 82% white, 6% black, 7% Hispanic, and 3% Asian. The median follow-up was 7.1 years (interquartile range, 3.4-11.1; maximum, 18). There were 24 ESKD and 252 death events during the study period. The 15-year risk of ESKD was 0.8% (95% confidence interval [95% CI], 0.4 to 1.6) for donors with hypertension (mean systolic BP, 138 mm Hg) versus 0.2% (95% CI, 0.1 to 0.4) for donors without hypertension (mean systolic BP, 123 mm Hg; adjusted hazard ratio, 3.04; 95% CI, 1.28 to 7.22; P=0.01). When predonation antihypertensive therapy was available, the risk of ESKD was 6.21-fold higher (95% CI, 1.20 to 32.17; P=0.03) for donors using antihypertensive therapy (mean systolic BP, 132 mm Hg) versus those not using antihypertensive therapy (mean systolic BP, 124 mm Hg). There was no significant association between donor hypertension and 15-year mortality (hazard ratio, 1.18; 95% CI, 0.84 to 1.66; P=0.34).

CONCLUSIONS

Compared with older donors without hypertension, older donors with hypertension had higher risk of ESKD, but not mortality, for 15 years postdonation. However, the absolute risk of ESKD was small.

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.

[Focusing on kidney transplantation in the elderly]

Due to the increase in life expectancy and the ageing of end-stage renal disease patients, the number of patients older than 65 years receiving a kidney transplant has been continuously growing over the last fifteen years. The benefits of renal transplantation compared to dialysis in terms of survival and quality of life have been shown in selected recipients over 65, or 70 years. However, the age remains the main limiting factor for the access to the waiting list, and the reluctance of the clinicians can be explained by the multiple comorbidities of these candidates, their limited life expectancy or the shortage of grafts. The challenge is to select the candidates who can benefit from renal transplantation, thanks to rigorous cardiovascular and neoplastic evaluation before enrolment and by taking into account the specific characteristics of elderly patients. The living donor appears to be the ideal option for elderly recipients, the alternative being the extended criteria donor, allowing waiting times to be limited. The choice of immunosuppressive therapy is also crucial in these patients at high risk of infectious and cardiovascular complications in whom the occurrence of acute rejection can have severe consequences. There are currently no specific recommendations for immunosuppression in elderly recipients, and we would need large-scale randomized studies to improve the prognosis of renal transplantation in this population.

The Long-Term Follow-up and Support for Living Organ Donors: A Center-Based Initiative Founded on Developing a Community of Living Donors

Transplant professionals recognize that the long-term follow-up of living organ donors is a priority, yet there has been no implemented solution to this problem. This critical gap is essential, because the transplant field is now emphasizing living donation as a means to address the organ shortage. We detail our living donor initiative, which sets several priorities we recognize as fundamental to persons who have donated organs at our transplant center. This intervention attempts to mitigate the donor and center factors that are known to contribute to the lack of long-term follow-up. Beyond that, our goals are aimed at providing ongoing engagement, wellness, clinical data accrual, laboratory follow-up, and social support for our living donors, in continuity. Our ultimate goal is to nurture the development of local living donor community networks by providing social engagement for current and past donors, which also serves as a platform for greater population education on the societal importance of living donation. This initiative is based on joint recognition by our transplant team and our hospital leadership that supporting the long-term welfare of living donors is essential to accomplishing the goal of expanding living donor transplantation. The transplant team and hospital missions are aligned, and both contribute resources to the initiative.