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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.

The incidence of live donor transplantation has declined over the past decade, and waitlisted candidates report substantial barriers to identifying a live donor. Since asking someone to donate feels awkward and unfamiliar, candidates are hesitant to ask directly and may be more comfortable with a passive approach. In collaboration with Facebook leadership (Facebook Inc., Menlo Park, CA), we developed a mobile application-an app-that enables waitlisted candidates to create a Facebook post about their experience with organ failure and their need for a live donor. We conducted a single-center prospective cohort study of 54 adult kidney-only and liver-only waitlisted candidates using the Facebook app. Cox proportional hazards models were used to describe donor referral on behalf of candidates using the app compared with matched controls. The majority of candidates who used the app reported it to be "good" or "excellent" with regard to the installation process (82.9%), readability (88.6%), simplicity (70.6%), clarity (87.5%) and the information provided (85.3%). Compared with controls, candidates using the Facebook app were _2.43 6.61_17.98 times more likely to have a donor come forward on their behalf (p < 0.001). The Facebook app is an easy-to-use instrument that enables waitlisted candidates to passively communicate with their social network about their need for a live donor.

Live kidney donors have an increased risk of end-stage renal disease (ESRD) compared with nondonors; however, it is unknown whether undetected, subclinical kidney disease exists at donation that subsequently contributes to this risk. To indirectly test this hypothesis, the authors followed the donated kidneys, by comparing the outcomes of 257 recipients whose donors subsequently developed ESRD with a matched cohort whose donors remained ESRD free. The compared recipients were matched on donor (age, sex, race/ethnicity, donor-recipient relationship), transplant (HLA mismatch, peak panel-reactive antibody, previous transplantation, year of transplantation), and recipient (age, sex, race/ethnicity, body mass index, cause of ESRD, and time on dialysis) risk factors. Median recipient follow-up was 12.5 years (interquartile range 7.4-17.9, maximum 20 years). Recipients of allografts from donors who developed ESRD had increased death-censored graft loss (74% versus 56% at 20 years; adjusted hazard ratio [aHR] 1.7; 95% confidence interval [CI] 1.5-2.0; p < 0.001) and mortality (61% versus 46% at 20 years; aHR 1.5; 95% CI 1.2-1.8; p < 0.001) compared with matched recipients of allografts from donors who did not develop ESRD. This association was similar among related, spousal, and unrelated nonspousal donors. These findings support a novel view of the mechanisms underlying donor ESRD: that of pre-donation kidney disease. However, biopsy data may be required to confirm this hypothesis.

Earlier studies reported inferior outcomes among black compared with white kidney transplant (KT) recipients. We examined whether this disparity improved in recent decades. Using the Scientific Registry of Transplant Recipients and Cox regression models, we compared all-cause graft loss among 63,910 black and 145,482 white adults who received a first-time live donor KT (LDKT) or deceased donor KT (DDKT) in 1990-2012. Over this period, 5-year graft loss after DDKT improved from 51.4% to 30.6% for blacks and from 37.3% to 25.0% for whites; 5-year graft loss after LDKT improved from 37.4% to 22.2% for blacks and from 20.8% to 13.9% for whites. Among DDKT recipients in the earliest cohort, blacks were 39% more likely than whites to experience 5-year graft loss (adjusted hazard ratio [aHR], 1.39; 95% confidence interval [95% CI], 1.32 to 1.47; P<0.001), but this disparity narrowed in the most recent cohort (aHR, 1.10; 95% CI, 1.03 to 1.18; P=0.01). Among LDKT recipients in the earliest cohort, blacks were 53% more likely than whites to experience 5-year graft loss (aHR, 1.53; 95% CI, 1.27 to 1.83; P<0.001), but this disparity also narrowed in the most recent cohort (aHR, 1.37; 95% CI, 1.17 to 1.61; P<0.001). Analyses revealed no statistically significant differences in 1-year or 3-year graft loss after LDKT or DDKT in the most recent cohorts. Our findings of reduced disparities over the last 22 years driven by more markedly improved outcomes for blacks may encourage nephrologists and patients to aggressively promote access to transplantation in the black community.

The Kidney Allocation System (KAS), a major change to deceased donor kidney allocation, was implemented in December 2014. Goals of KAS included directing the highest-quality organs to younger/healthier recipients and increasing access to deceased donor kidney transplantation (DDKT) for highly sensitized patients and racial/ethnic minorities. Using national registry data, we compared kidney distribution, DDKT rates for waitlist registrants, and recipient characteristics between January 1, 2013, and December 3, 2014 (pre-KAS) with those between December 4, 2014, and August 31, 2015 (post-KAS). Regional imports increased from 8.8% pre-KAS to 12.5% post-KAS; national imports increased from 12.7% pre-KAS to 19.1% post-KAS (P<0.001). The proportion of recipients >30 years older than their donor decreased from 19.4% to 15.0% (P<0.001). The proportion of recipients with calculated panel-reactive antibody =100 increased from 1.0% to 10.3% (P<0.001). Overall DDKT rate did not change as modeled using exponential regression adjusting for candidate characteristics (P=0.07). However, DDKT rate (incidence rate ratio, 95% confidence interval) increased for black (1.19; 1.13 to 1.25) and Hispanic (1.13; 1.05 to 1.20) candidates and for candidates aged 18-40 (1.47; 1.38 to 1.57), but declined for candidates aged >50 (0.93; 0.87 to 0.98 for aged 51-60 and 0.90; 0.85 to 0.96 for aged >70). Delayed graft function in transplant recipients increased from 24.8% pre-KAS to 29.9% post-KAS (P<0.001). Thus, in the first 9 months under KAS, access to DDKT improved for minorities, younger candidates, and highly sensitized patients, but declined for older candidates. Delayed graft function increased substantially, possibly suggesting poorer long-term outcomes.

Choosing between multiple living kidney donors, or evaluating offers in kidney paired donation, can be challenging because no metric currently exists for living donor quality. Furthermore, some deceased donor (DD) kidneys can result in better outcomes than some living donor kidneys, yet there is no way to compare them on the same scale. To better inform clinical decision-making, we created a living kidney donor profile index (LKDPI) on the same scale as the DD KDPI, using Cox regression and adjusting for recipient characteristics. Donor age over 50 (hazard ratio [HR] per 10 years = 1.15 1.241.33 ), elevated BMI (HR per 10 units = 1.01 1.091.16 ), African-American race (HR = 1.15 1.251.37 ), cigarette use (HR = 1.09 1.161.23 ), as well as ABO incompatibility (HR = 1.03 1.271.58 ), HLA B (HR = 1.03 1.081.14 ) mismatches, and DR (HR = 1.04 1.091.15 ) mismatches were associated with greater risk of graft loss after living donor transplantation (all p < 0.05). Median (interquartile range) LKDPI score was 13 (1-27); 24.2% of donors had LKDPI < 0 (less risk than any DD kidney), and 4.4% of donors had LKDPI > 50 (more risk than the median DD kidney). The LKDPI is a useful tool for comparing living donor kidneys to each other and to deceased donor kidneys.

Since March 26, 2012, the Kidney Donor Profile Index (KDPI) has been provided with all deceased-donor kidney offers, with the goal of improving the expanded criteria donor (ECD) indicator. Although an improved risk index may facilitate identification and transplantation of marginal yet viable kidneys, a granular percentile system may reduce provider-patient communication flexibility, paradoxically leading to more discards ("labeling effect"). We studied the discard rates of the kidneys recovered for transplantation between March 26, 2010 and March 25, 2012 ("ECD era," N = 28 636) and March 26, 2012 and March 25, 2014 ("KDPI era," N = 29 021) using Scientific Registry of Transplant Recipients (SRTR) data. There was no significant change in discard rate from ECD era (18.1%) to KDPI era (18.3%) among the entire population (adjusted odds ratio [aOR] = 0.97 1.041.10 , p = 0.3), or in any KDPI stratum. However, among kidneys in which ECD and KDPI indicators were discordant, "high risk" standard criteria donor (SCD) kidneys (with KDPI > 85) were at increased risk of discard in the KDPI era (aOR = 1.07 1.421.89 , p = 0.02). Yet, recipients of these kidneys were at much lower risk of death (adjusted Risk Ratio [aRR] = 0.56 0.770.94 at 2 years posttransplant) compared to those remaining on dialysis waiting for low-KDPI kidneys. Our findings suggest that there might be an unexpected, harmful labeling effect of reporting a high KDPI for SCD kidneys, without the expected advantage of providing a more granular risk index.

BACKGROUND: Kidney donors can develop end-stage renal disease (ESRD) after donation, but the outcomes of those who do remain poorly characterized. METHODS: Using United States Renal Data System and Scientific Registry for Transplant Research data, we compared access to kidney transplantation (KT), time from ESRD to listing, time from listing to KT, and post-KT graft failure and death between donors and matched nondonors with ESRD. RESULTS: Among 99 donors between April 1994 and November 2011 who developed ESRD, 78 initially received dialysis (of whom 37 listed for KT, 2 received live donor KT without listing, and 39 never listed for or received a KT), 20 listed preemptively (of whom 19 were subsequently transplanted), and 1 received a preemptive live donor KT without listing or ever receiving dialysis. Donors were listed earlier (median time to listing, 17 months vs 120 for nondonors; P < 0.001), received KT earlier (median waiting time, 2.8 months vs 21.5 for nondonors; P < 0.001), and received 13% live donor, 87% standard criteria, and 0% expanded criteria deceased donor KT (39%, 50%, and 11% in nondonors). Post-KT graft (adjusted hazard ratio, 1.9; 95% confidence interval, 0.9 to 4.1; P = 0.1) and patient (adjusted hazard ratio, 0.7; 95% confidence interval, 0.2 to 2.4; P = 0.5) survival were comparable in donors and nondonors. CONCLUSIONS: Our finding that 39 of 99 donors who developed ESRD never listed for a transplant warrants further study to ascertain why these donors with ESRD never gained access to the waiting list.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially.