Implementation Of Kidney Allocation System Research Articles

A2/A2B to B deceased donor kidney transplantation in the Kidney Allocation System era

Kidney transplantation from blood type A2/A2B donors to type B recipients (A2→B) has increased dramatically under the current Kidney Allocation System (KAS). Among living donor transplant recipients, A2-incompatible transplants are associated with an increased risk of all-cause and death-censored graft failure. In light of this, we used data from the Scientific Registry of Transplant Recipients from December 2014 until June 2022 to evaluate the association between A2→B listing and time to deceased donor kidney transplantation (DDKT) and post-DDKT outcomes for A2→B recipients. Among 53 409 type B waitlist registrants, only 12.6% were listed as eligible to accept A2→B offers ("A2-eligible"). The rates of DDKT at 1-, 3-, and 5-years were 32.1%, 61.4%, and 72.1% among A2-eligible candidates and 14.1%, 29.9%, and 44.1% among A2-ineligible candidates, with the former experiencing a 133% higher rate of DDKT (Cox weighted hazard ratio (wHR) = 2.192.332.47; P < .001). The 7-year adjusted mortality was comparable between A2→B and B-ABOc (type B/O donors to B recipients) recipients (wHR 0.780.941.13, P = .5). Moreover, there was no difference between A2→B vs B-ABOc DDKT recipients with regards to death-censored graft failure (wHR 0.771.001.29, P > .9) or all-cause graft loss (wHR 0.820.961.12, P = .6). Following its broader adoption since the implementation of the kidney allocation system, A2→B DDKT appears to be a safe and effective transplant modality for eligible candidates. As such, A2→B listing for eligible type B candidates should be expanded.

The unfinished journey toward transplant equity: an analysis of racial/ethnic disparities for children after the implementation of the Kidney Allocation System in 2014.

Disparities in pediatric kidney transplantation (KT) result in reduced access and worse outcomes for minority children. We assessed the impact of recent systems changes on these disparities. This is a retrospective cohort study of pediatric patients utilizing data from the US Renal Data System (n = 7547) and Scientific Registry of Transplant Recipients (n = 6567 waitlisted and n = 6848 transplanted patients). We compared access to transplantation, time to deceased donor kidney transplant (DDKT), and allograft failure (ACGF) in the 5years preceding implementation of the Kidney Allocation System (KAS) to the 5years post-KAS implementation 2010-2014 vs. 2015-2019, respectively. Compared to the pre-KAS era, post-KAS candidates were more likely to be pre-emptively listed (26.8% vs. 38.1%, p < 0.001), pre-emptively transplanted (23.8% vs. 28.0%, p < 0.001), and less likely to have private insurance (35.6% vs. 32.3%, p = 0.01), but these were not uniform across racial groups. Compared to white children, Black and Hispanic children had a lower likelihood of transplant listing within 2years of first dialysis service (aHR 0.590.670.76 and 0.730.820.92, respectively) in the post-KAS era. Time to DDKT was comparable across all racial groups in the post-KAS era. Compared to white children, Black DDKT recipients have more 5-year ACGF (aHR 1.001.432.06 p = 0.05) while there was no difference in 3- or 5-year ACGF among LDKT recipients. After KAS implementation, there is equity in time to DDKT. Pre-KAS increased hazard of ACGF among Black children has decreased in the post-KAS era; however, persistent disparities exist in time to transplant listing among Black and Hispanic children when compared to white children. A higher resolution version of the Graphical abstract is available as Supplementary information.

Referral and Evaluation for Kidney Transplantation Following Implementation of the 2014 National Kidney Allocation System

The national kidney allocation system (KAS) implemented in December 2014 in the United States redefined the start of waiting time from the time of waitlisting to the time of kidney failure. Waitlisting has declined post-KAS, but it is unknown if this is due to transplant center practices or changes in dialysis facility referral and evaluation. The purpose of this study was to assess the impact of the 2014 KAS policy change on referral and evaluation for transplantation among a population of incident and prevalent patients with kidney failure. Cohort study. 37,676 incident (2012-2016) patients in Georgia, North Carolina, and South Carolina identified within the US Renal Data System at 9 transplant centers and followed through December 2017. A prevalent population of 6,079 patients from the same centers receiving maintenance dialysis in 2012 but not referred for transplantation in2012. KAS era (pre-KAS vs post-KAS). Referral for transplantation, start of transplant evaluation, and waitlisting. Multivariable time-dependent Cox models for the incident and prevalent population. Among incident patients, KAS was associated with increased referrals (adjusted HR, 1.16 [95% CI, 1.12-1.20]) and evaluation starts among those referred (adjusted HR, 1.16 [95% CI, 1.10-1.21]), decreased overall waitlisting (adjusted HR, 0.70 [95% CI, 0.65-0.76]), and lower rates of active waitlisting among those evaluated compared to the pre-KAS era (adjusted HR, 0.81 [95% CI, 0.74-0.90]). Among the prevalent population, KAS was associated with increases in overall waitlisting (adjusted HR, 1.74 [95% CI, 1.15-2.63]) and active waitlisting among those evaluated (adjusted HR, 2.01 [95% CI, 1.16-3.49]), but had no significant impact on referral or evaluation starts among those referred. Limited to 3 states, residual confounding. In the southeastern United States, the impact of KAS on steps to transplantation was different among incident and prevalent patients with kidney failure. Dialysis facilities referred more incident patients and transplant centers evaluated more incident patients after implementation of KAS, but fewer evaluated patients were placed onto the waitlist. Changes in dialysis facility and transplant center behaviors after KAS implementation may have influenced the observed changes in access to transplantation.

Impact of Change in Allocation Score Methodology on Post Kidney Transplant Average Length of Stay.

BackgroundIn December 2014, a new Kidney Allocation System (KAS) was implemented nationwide to improve access and quality of care to historically disadvantaged patients. However, no study to date has examined the relationship between the KAS and potential changes in hospital length of stay (LOS). This study aimed to examine the relationship between the KAS implemented in December 2014 and potential changes in hospital LOS.MethodsWe used data from the Florida Agency for Health Care Administration on kidney transplant surgeries completed between 2011 and 2018. A cross-sectional cohort study design included seven hospitals that performed kidney transplants for the duration of the study. A propensity score matching approach was used to examine the relationship between KAS and LOS. All acute general medical and surgical hospitals in Florida that performed kidney transplant surgery were included in the analysis.ResultsWe included 7,795 patients, 6,119 discharged to home, and 1,676 discharged to home with home health services after transplant. The average LOS prior to KAS was 6.52 days and 6.08 days post KAS. Propensity matched results show that patients transferred to home experienced a decrease in the LOS (coefficient (β) = -0.68; 95% confidence interval (CI): -0.95, -0.42) after the new allocation score was implemented. Similarly, patients transferred to home with home health experienced a decrease in the LOS (β = -1.90; 95% CI: -2.69, -1.11) after the new allocation was implemented.ConclusionIn conclusion, results indicate that KAS implementation did not add a burden on the health system by increasing LOS when considering patients with similar characteristics before and after KAS implementation. KAS is an important policy change that appears to not negatively affect the LOS when sicker patients could receive a kidney transplant. Our findings improve our understanding of the KAS policy and its influence on the health system.

Trends in the procurement and discard of kidneys from deceased donors with acute kidney injury

Kidney allocation trends from deceased donors with acute kidney injury (AKI) have not been characterized since initial Kidney Donor Profile Index reporting in 2012 and its use under the revised Kidney Allocation System (KAS) in 2014. We conducted a retrospective analysis of US registry data to characterize kidney procurement and discard trends in deceased donors with AKI, defined by ≥50% or ≥0.3mg/dl (≥4.0mg/dl or ≥200% for stage 3) increase in terminal serum creatinine from admission. From 2010 to 2020, 172410kidneys were procured from 93341 deceased donors 16years or older; 34984kidneys were discarded (17559 from AKI donors). The proportion of stage 3 AKI donors doubled from 6% (412/6841) in 2010 to 12% (1365/11493) in 2020. Procurement of stage 3 AKI kidneys increased from 51% (423/824) to 80% (2183/2730). While discard of stage 3 AKI kidneys increased from 41% (175/423) in 2010 to 44% (960/2183) in 2020, this increase was not statistically significant in interrupted time-series analysis following KAS implementation (slope difference -0.41 [-3.22, 2.4], and level change 3.09 [-6.4, 12.6]). In conclusion, the absolute number of stage 3 AKI kidneys transplanted has increased. Ongoing high discard rates of these kidneys suggest opportunities for improved utilization.

Return to work after deceased donor kidney transplant under the kidney allocation system.

The Kidney Allocation System (KAS) includes a scoring system to match transplant candidate life expectancy with expected longevity of the donor kidney, and a backdating policy that gives waitlist time credit to patients waitlisted after starting dialysis treatment (post-dialysis). We estimated the effect of the KAS on employment among patient subgroups targeted by the policy. We used a sample selection model to compare employment after transplant before and after KAS implementation among patients on the kidney-only transplant waitlist between December 4, 2011 and December 31, 2017. Post-dialysis transplant recipients aged 18-49 were significantly more likely to be employed 1-year post transplant in the post-KAS era compared to the pre-KAS era. Transplant recipients aged 35-64 with no dialysis treatment were significantly less likely to be employed 1year after transplant in the post-KAS era compared to the pre-KAS era. This study provides the first assessment of employment after DDKT under the KAS and provides important information about both the methods used to measure employment after transplant and the outcome under the KAS. Changes in employment after DDKT among various patient subgroups have important implications for assessing long-term patient and societal effects of the KAS and organ allocation policy.

Impact of the 2014 kidney allocation system changes on trends in A2/A2B into B kidney transplantation and organ procurement organization reporting of donor subtyping.

The current kidney allocation system (KAS) preferentially allocates kidneys from blood type A2 or A2B (A/A2B) donors to blood type B candidates. We used national data to evaluate center-level performance of A2/A2B to B transplants, and organ procurement organization (OPO) reporting of type A or AB donor subtyping, in 5-year time periods prior to (2009-2014) and following (2015-2019) KAS implementation. The number of centers performing A2/A2B to B transplants increased from 17 pre-KAS to 76 post-KAS, though this still represents only a minority of centers (7.3% pre-KAS and 32.6% post-KAS). For high-performing centers, the median net increase in A2/A2B to B transplants was 19 cases (range -2-72) per center in the 5 years post-KAS. The median net increase in total B recipient transplants was 21 cases (range -17-119) per center. Despite requirements for performance of subtyping, in 2019 subtyping was reported on only 56.4% of A/AB donors. This translates into potential missed opportunities for B recipients, and even post-KAS up to 2322 A2/A2B donor kidneys may have been allocated for transplantation as A/AB. Further progress must be made both at center and OPO levels to broaden implementation of A2/A2B to B transplants for the benefit of underserved recipients.

Systematic Review of Disparities in Kidney Transplantation Prior to Implementation of the Kidney Allocation System and Directions for Research

Major changes were made to the U.S. kidney allocation system (KAS) on December 4, 2014, in the effort to address disparities in kidney transplantation (KT) and achieve equity in organ allocation. Research is necessary to examine whether KAS achieved its goal; first, a firm understanding of the disparities that existed prior to implementation of KAS is needed. This systematic review examined the literature on disparities in access to deceased donor KT (DDKT) after listing in the pre-KAS era and discussed mechanisms to explain these disparities. Thirty-two articles were included. Racial, gender, age, socioeconomic, physiologic, geographic, and health care system disparities existed in the pre-KAS era. Findings of this review will inform the agenda for future disparities research in the post-KAS era.

4354 The Impact of the 2014 Kidney Allocation System on Waitlisting Rates at the Dialysis Facility Level

OBJECTIVES/GOALS: The new Kidney Allocation System (KAS) was implemented in 2014 and it is not fully understood how its changes to patient incentives may have impacted dialysis facility waitlisting rates. We examine differences in facility performance and how such differences may have been impacted by this policy change. METHODS/STUDY POPULATION: We used Dialysis Facility Report data from 2011 to 2017 to study waitlisting rates at 3,392 dialysis facilities in the US, using waitlisting counts in the numerator, and the total number of ESRD patients in a facility as the denominator. We examined changes in waitlisting rates over by year at the facility, regional, and national level, and report national trends in waitlisting pre- and post-KAS. Facilities were stratified based on waitlisting rate in 2011 and then we examined whether each facility moved into a higher or lower quartile or stayed in the same quartile in 2017. RESULTS/ANTICIPATED RESULTS: Among n = 3,392 dialysis facilities, the average change in dialysis facility waitlisting rates from 2011 to 2017 was −4.74 percentage points (range -54.4% to 42.3%). Average change in dialysis facility waitlisting rates from 2011 to 2014 was −0.57 percentage points while the average change in dialysis facility waitlisting rates from 2014 to 2017 was −4.17 percentage points. Half of facilities in the 2011 lowest quartile remained in the lowest quartile in 2017; 45% of facilities in the top 2011 quartile dropped into a lower quartile. The middle 2 quartiles were fairly evenly split between worsening, improving, and not changing. DISCUSSION/SIGNIFICANCE OF IMPACT: Average waitlisting rates have declined since KAS implementation. Many facilities switched quartiles from 2011-17 suggesting that facility waitlisting rates are unstable over time. The decline in waitlisting rates post-KAS suggests that new allocation rules may be discouraging patients and/or providers from getting ESRD patients waitlisted.

Trends in Disparities in Preemptive Kidney Transplantation in the United States.

Long wait times for deceased donor kidneys and low rates of preemptive wait-listing have limited preemptive transplantation in the United States. We aimed to assess trends in preemptive deceased donor transplantation with the introduction of the new Kidney Allocation System (KAS) in 2014 and identify whether key disparities in preemptive transplantation have changed. We identified adult deceased donor kidney transplant recipients in the United States from 2000 to 2018 using the Scientific Registry of Transplant Recipients. Preemptive transplantation was defined as no dialysis before transplant. Associations between recipient, donor, transplant, and policy era characteristics and preemptive transplantation were calculated using logistic regression. To test for modification by KAS policy era, an interaction term between policy era and each characteristic of interest was introduced in bivariate and adjusted models. The proportion of preemptive transplants increased after implementation of KAS from 9.0% to 9.8%, with 1.10 (95% confidence interval [95% CI], 1.06 to 1.14) times higher odds of preemptive transplantation post-KAS compared with pre-KAS. Preemptive recipients were more likely to be white, older, female, more educated, hold private insurance, and have ESKD cause other than diabetes or hypertension. Policy era significantly modified the association between preemptive transplantation and race, age, insurance status, and Human Leukocyte Antigen zero-mismatch (interaction P<0.05). Medicare patients had a significantly lower odds of preemptive transplantation relative to private insurance holders (pre-KAS adjusted OR, [aOR] 0.26; [95% CI, 0.25 to 0.27], to 0.20 [95% CI, 0.18 to 0.22] post-KAS). Black and Hispanic patients experienced a similar phenomenon (aOR 0.48 [95% CI, 0.45 to 0.51] to 0.41 [95% CI, 0.37 to 0.45] and 0.43 [95% CI, 0.40 to 0.47] to 0.40 [95% CI, 0.36 to 0.46] respectively) compared with white patients. Although the proportion of deceased donor kidney transplants performed preemptively increased slightly after KAS, disparities in preemptive kidney transplantation persisted after the 2014 KAS policy changes and were exacerbated for racial minorities and Medicare patients.

Association of Racial Disparities With Access to Kidney Transplant After the Implementation of the New Kidney Allocation System

Inactive patients on the kidney transplant wait-list have a higher mortality. The implications of this status change on transplant outcomes between racial/ethnic groups are unknown. To determine if activity status changes differ among races/ethnicities and levels of sensitization, and if these differences are associated with transplant probability after implementation of the Kidney Allocation System. A multistate model was constructed from the Organ Procurement and Transplantation Network kidney transplant database (December 4, 2014, to September 8, 2016). The time interval followed Kidney Allocation System implementation and provided at least 1-year follow-up for all patients. The model calculated probabilities between active and inactive status and the following competing risk outcomes: living donor transplant, deceased donor transplant, and death/other. This retrospective cohort study included 42 558 patients on the Organ Procurement and Transplantation Network kidney transplant wait-list following Kidney Allocation System implementation. To rule out time-varying confounding from relisting, analysis was limited to first-time registrants. Owing to variations in listing practices, primary center listing data were used for dually listed patients. Individuals listed for another organ or pancreatic islets were excluded. Analysis began July 2017. Probabilities were determined for transitions between active and inactive status and the following outcome states: active to living donor transplant, active to deceased donor transplant, active to death/other, inactive to living donor transplant, inactive to deceased donor transplant, and inactive to death/other. The median (interquartile range) age at listing was 55.0 (18.0-89.0) years, and 26 535 of 42 558 (62.4%) were men. White individuals were 43.3% (n = 18 417) of wait-listed patients, while black and Hispanic individuals made up 27.8% (n = 11 837) and 19.5% (n = 8296), respectively. Patients in the calculated plasma reactive antibody categories of 0% or 1% to 79% showed no statistically significant difference in transplant probability among races/ethnicities. White individuals had an advantage in transplant probability over black individuals in calculated plasma reactive antibody categories of 80% to 89% (hazard ratio [HR], 1.8 [95% CI, 1.4-2.2]) and 90% or higher (HR, 2.4 [95% CI, 2.1-2.6]), while Hispanic individuals had an advantage over black individuals in the calculated plasma reactive antibody group of 90% or higher (HR, 2.5 [95% CI, 2.1-2.8]). Once on the inactive list, white individuals were more likely than Hispanic individuals (HR, 1.2 [95% CI, 1.17-1.3]) or black individuals (HR, 1.4 [95% CI, 1.3-1.4]) to resolve issues for inactivity resulting in activation. For patients who are highly sensitized, there continues to be less access to kidney transplant in the black population after the implementation of the Kidney Allocation System. Health disparities continue after listing where individuals from minority groups have greater difficulty in resolving issues of inactivity.

The national landscape of deceased donor kidney transplantation for the highly sensitized: Transplant rates, waitlist mortality, and posttransplant survival under KAS.

Deceased donor kidney transplantation (DDKT) rates for highly sensitized (HS) candidates increased early after implementation of the Kidney Allocation System (KAS) in 2014. However, this may represent a bolus effect, and a granular investigation of the current state of DDKT for HS candidates remains lacking. We studied 270722 DDKT candidates from the SRTR from 12/4/2011 to 12/3/2014 ("pre-KAS") and 12/4/2014 to 12/3/2017 ("post-KAS"), analyzing DDKT rates for HS candidates using adjusted negative binomial regression. Post-KAS, candidates with the highest levels of sensitization had an increased DDKT rate compared with pre-KAS (cPRA 98% adjusted incidence rate ratio [aIRR]:1.27 1.772.46 P=.001, cPRA 99% aIRR:3.18 4.365.98 P<.001, cPRA 99.5-99.9% aIRR:16.91 24.2934.89 P<.001, and cPRA 99.9%+ aIRR:8.79 11.5815.26 P<.001). To determine whether these changes produced more equitable access to DDKT, we compared DDKT rates of HS to non-HS candidates (cPRA 0-79%). Post-KAS, cPRA, 98% candidates had an equivalent DDKT rate (aIRR:0.65 0.941.36 , P=.8) to non-HS candidates, whereas 99% candidates had a higher DDKT rate (aIRR:1.19 1.682.38 , P=.02). Although cPRA 99.5-99.9% candidates had an increased DDKT rate (aIRR:2.46 3.504.98 , P<.001) compared to non-HS candidates, cPRA 99.9%+ candidates had a significantly lower DDKT rate (aIRR:0.29 0.400.56 , P<.001). KAS has improved access to DDKT for HS candidates, although substantial imbalance exists between cPRA 99.5-99.9% and 99.9%+ candidates.

KAS Turns Four: The State of Deceased Donor Kidney Allocation in the U.S.

Background: This study examines very recent trends in deceased donor kidney transplantation to assess the performance of the kidney allocation system (KAS), implemented December 4, 2014, and whether bolus effects associated with KAS have stabilized nearly four years after implementation. Methods: The overall number of deceased donor kidney transplants, as well as the proportion of transplants by recipient and transplant characteristics, were calculated monthly from December 2013 through September 2018 and examined graphically. Kidney discard rates – the percentage of kidneys recovered for transplant not transplanted – were analyzed overall and stratified by donor Kidney Donor Profile Index (KDPI). Delayed graft function (DGF) was defined as the recipient requiring dialysis within one week of transplant; monthly rates were examined graphically. We also surveyed other published research to round out our assessment of KAS’s impact. Results: Marked bolus effects, particularly a sharp increase in transplants to highly sensitized and high dialysis time recipients, were associated with KAS implementation but have since stabilized. Transplant access has improved for African American candidates, who now receive a proportion of transplants comparable to their representation on the waiting list. Subtype-compatible (“A2/A2B to B”) transplants have increased sharply but are still numerically small (~20/month) and may have plateaued. Though the overall kidney discard rate has not changed appreciably over the past five years, the rate for KDPI 35-85% kidneys has trended slightly downward since 2017. After initially rising with KAS, DGF rates have tapered but still remain slightly above pre-KAS levels. One-year graft and patient survival remain excellent. Conclusions: The number of deceased donor kidney transplants has reached an all-time high and continues to rise, a boon for the nearly 100,000 patients with kidney failure on the waiting list. Several key bolus effects that were anticipated with KAS did indeed materialize, drastically changing the characteristics of the initial wave of post-KAS recipients. These bolus effects have since tapered, suggesting KAS has, by and large, reached a steady state. KAS has improved equity across ethnicities and levels of sensitization but did not attempt to resolve geographic inequities. Published research has confirmed that substantial geographic disparities remain. The goal of increasing utilization of kidneys at high risk of discard has not been met. Numerous policy changes and system improvement initiatives have been proposed, many of which are currently underway or pending implementation, to improve organ utilization.

Utilization of Standard Criteria Donor and Expanded Criteria Donor Kidneys After Kidney Allocation System Implementation.

BackgroundImplementation of the Kidney Allocation System (KAS) changed how kidneys are allocated and the information on which organ utilization decisions are based. We aimed to evaluate how KAS implementation changed kidney utilization and recipient outcomes.Material/MethodsUsing the United Network for Organ Sharing database, we identified recipients of kidney transplants from donors with kidney donor profile index (KDPI) of 61–90% in the 5-years pre- and 18-months post-KAS implementation and examined patient and graft survival and donor kidney discard rates based on standard criteria donor (SCD) or expanded criteria donor (ECD) status.ResultsThe proportion of ECD kidneys was unchanged pre- versus post-KAS. Post-KAS, SCD kidneys were less likely to be transplanted into young recipients while ECD kidneys were more likely to be transplanted. SCD kidneys in the post-KAS period conferred a 1.42 (95% CI: 1.18–1.73) times higher adjusted mortality and 2% lower 1-year survival (94.2% vs. 96.2%, P<0.001) but had unchanged graft failure compared to pre-KAS. For ECD kidneys, there was no difference in mortality or graft survival. The discard rate increased after KAS for both SCD and ECD kidneys (P<0.05) but was not different between SCD and ECD kidneys for any KDPI group.ConclusionsAfter KAS implementation, patient survival for recipients of SCD kidneys was significantly worse.

P141Kas three years later: life after the bolus effect

Aim The new Kidney Allocation System (KAS) resulted in a significant bolus in the transplantation of 99–100 CPRA candidates due to increased priority. We examined the impact of an individualized approach to maintain a high transplant rate for these candidates three years after KAS implementation. Methods The early post-KAS period (EPKAS) was defined as deceased donor transplants occurring in 2015 and 2 year post-KAS period (2YPKAS) as 2016 and 2017. Donor specific antibody positivity (DSA+) was defined by single antigen bead assays performed pre-transplant (±7 days) and 90 days post-transplant (±14 days). Flow cytometric crossmatches (FCXM) were performed using the pre-transplant serum, donor lymphocytes, and acquisition on a BD Canto instrument. Data from SRTR was used to assess outcome at 1 year for our center and nationally. Results Nationally, transplantation of 99–100 CPRA candidates rose sharply (17.7%) in the EPKAS period and has since tapered (10%) in the 2YPKAS period. At our center, we observed a similar increase in the EPKAS period (16%, n = 30) but this trend increased further during the 2YPKAS period (28%, n = 75). In the EPKAS period, 60% (n = 18) of 99–100 CPRA recipients were DSA+ and 39% (n = 7) of DSA+ recipients were also FCXM positive. 61% (n = 11) of DSA+ recipients during this period had persistent DSA at 90 + days post-transplant. In the 2YPKAS period, a similar percentage (57%, n = 43) of 99–100 CPRA recipients were DSA+ at time of transplant; however, fewer (8%, n = 6) DSA+ recipients were also FCXM+. Correspondingly, fewer (34%, n = 26) DSA+ recipients had persistent DSA at 90 + days post-transplant. A total of five (5%) candidates in the post-KAS era experienced a rise in DSA post-transplant that required intervention. The hazard ratio for 1 year graft survival was 1.05 for our center and 1.00 nationally. Conclusions Our center continues to successfully transplant 99–100 CPRA candidates at a rate higher than the national average. This has been achieved through a personalized approach for defining unacceptable antigens and assessing donor offers, transplanting across DSA barriers, and a stringent post-transplant monitoring protocol. Refinement in our approach in the 2 year post-KAS has resulted in more compatible transplants, less DSA persistence, and the maintenance of good clinical outcomes. A.M. Jackson: 3. Speaker’s Bureau; Company/Organization; Thermo-Fisher.

Impact of the New Kidney Allocation System A2/A2B--&gt; B Policy on Access to Transplantation among Minority Candidates

Introduction Blood group B kidney transplant candidates, many of whom represent ethnic minorities, have historically had diminished access to deceased donor kidney transplantation (DDKT). However, due to the decreased antigenicity of the blood group subtype A2, A2 incompatible (A2i) transplantation can be achieved successfully without the need for additional immunomodulation. Therefore, in an effort to address the ethnic and blood group disparity in access to DDKT, the new national kidney allocation system (KAS) implemented in December 2014, preferentially allocates deceased donor kidneys from blood group A2 and A2B donors to blood group B recipients. To date, no study has examined the impact of KAS on A2i DDKT rates overall for blood group B recipients or among ethnic minorities. Materials and Methods A case-control study of adult blood group B DDKT recipients was performed from 2013 through 2017, as reported to the Scientific Registry of Transplant Recipients. The likelihood of A2i DDKT was compared from the pre-KAS period (1/1/2013-12/3/2014) to the post-KAS period (12/4/2014-2/28/2017) using multivariate logistic regression. Results Following the implementation of KAS, there was a 4.9-fold increase in the likelihood of A2i DDKT for blood group B recipients, compared to the pre-KAS period (OR 4.92, 95% CI: 3.67-6.60). Likewise, the number of transplant centers that had performed one or more A2/A2B to B DDKT increased from 6.9% in the pre-KAS period, to 26.4% post-KAS. However, compared to White blood group B recipients, there was no change in the likelihood of A2i DDKT in the post-KAS era among the following minority groups: African Americans (aOR 0.90, 95% CI: 0.43-1.86 pre-KAS, aOR 0.91, 95%CI: 0.69-1.21 post-KAS); Asians (aOR 1.23, 95% CI 0.49-3.04 pre-KAS, aOR 1.02 95%CI 0.68-1.53 post-KAS); and Hispanics (aOR 1.32, 95% CI 0.51-3.42 pre-KAS, aOR 1.38, 95% CI 0.94-2.03 post-KAS)(Table). Conclusion Although the implementation of KAS has resulted in an increase in A2i DDKT for blood group B recipients, the likelihood of A2i DDKT among minorities, relative to Whites, was not improved. Further discussion regarding A2/A2B --> B policy revisions aimed to increase access to DDKT for ethnic minorities is warranted.American Society of Transplant Surgeons (ASTS) Diversity Affairs Committee. National Institutes of Health- National Research Service Award, through Grant Award Number T32 DK007545. Health Resources and Services Administration contract 234-2005-37011C.

Evolving Trends in Racial Disparities for Peri-Operative Outcomes with the New Kidney Allocation System (KAS) Implementation.

To improve kidney transplant allocation equitability, a new Kidney Allocation System (KAS) was implemented December 4, 2014. The purpose of this study was to determine if the impact of KAS on peri-operative outcomes differed by recipient race/ethnicity. This was a time series analysis using data aggregated in monthly intervals from October 2012 through September 2015 using the University HealthSystem Consortium (UHC). This includes national data aggregated at the center level of all US kidney transplant centers that participate in the UHC (416 centers). Segmented regression with interaction terms was used to determine the impact of KAS on outcomes and differences by race/ethnicity. A total of 28,809 deceased donor kidney transplants were included with 25months of pre-KAS data and 10months of post-KAS data. After KAS implementation, the estimated transplant rate per month decreased significantly for Caucasians by 17.6 cases per month (p = 0.0001), and increased significantly for AAs by 37.8 (p = 0.0001), Hispanics by 16.3 (p = 0.0001), and other races by 8.2 cases per month (p = 0.0001). Delayed graft function, 7- and 14-day readmissions significantly increased after KAS, which did not differ by race. Hispanics saw a 7.7% decrease in ICU admissions after KAS, which differed as compared to other racial/ethnic cohorts (p = 0.0026). Costs of kidney transplantation increased significantly after KAS in all groups except Hispanics. Mortality, length of stay, in-hospital complications, and 30-day readmissions were not significantly impacted by KAS, also not differing by race/ethnicity. KAS had substantial impact on transplant rates by race/ethnicity. KAS also led to increased costs, readmissions, and delayed graft function (DGF) across all racial/ethnic groups. The impact of KAS on ICU cases solely within Hispanics requires further investigation into potential etiologies.

The kidney allocation system does not appropriately stratify risk of pediatric donor kidneys: Implications for pediatric recipients.

Kidney Allocation System (KAS) was enacted in 2014 to improve graft utility, while facilitating transplantation of highly-sensitized patients and preserving pediatric access to high-quality kidneys. Central to this system is the Kidney Donor Profile Index (KDPI), a metric intended to predict transplant outcomes based on donor characteristics but derived using only adult donors. We posited that KAS had inadvertently altered the profile and quantity of kidneys made available to pediatric recipients. This question arose from our observation that most pediatric donors carry a KDPI over 35 and have therefore been rendered relatively inaccessible to pediatric recipients under KAS. Here we explore early trends in pediatric transplantation following KAS, including: (i) use of pediatric donors, (ii) use of Public Health System (PHS) high infectious risk donors, (iii)wait time, and (iv) living donor transplantation. We note some concerning preliminary changes following KAS implementation, including the allocation of fewer deceased donor pediatric kidneys to children and stagnation in pediatric wait times. Moreover, the poor predictive power of the KDPI for adult donors appears to be even worse when applied to pediatric donors. These early trends warrant further observation and consideration of changes in pediatric kidney allocation if they persist.

Impact of the New Kidney Allocation System on Perioperative Outcomes and Costs in Kidney Transplantation

In December 2014, a new kidney allocation system (KAS) was implemented nationwide with the goal of improving longevity matching, increasing access to sensitized patients, and improving racial/ethnic disparities. National cohort study of US kidney transplantation programs, analyzing hospital-level outcomes (October 2012 to June 2016) using University HealthSystem Consortium data. In-hospital outcomes and costs were analyzed for trends over time using interrupted time series analysis with segmented regression. There were 38,016 kidney transplantation procedures analyzed during the 3.8-year period. Over time, there was a mean increase of 2.7 cases/month (95% CI-0.02 to 5.4; p= 0.059), unaffected by KAS (18.9 case increase; p= 0.5601). Implementation of KAS led to significant changes in patient demographics, including a decrease in age (-2.8 years; p<0.001), increase in number of African Americans (3.8%; p < 0.001), decrease in number of Caucasians (6.0%; p < 0.001), increase in number of Hispanics (2.9%; p < 0.001), increase in congestive heart failure (1.3%; p < 0.001), and decrease in diabetes with complications (4.0%; p < 0.001). The KAS had no impact on length of stay (0.12 days; 95% CI-0.11 to 0.35), length of stay index (0.01; 95% CI-0.03 to 0.05), ICU cases, ICU length of stay, patient safety indicators, or in-hospital mortality. The KAS led to a significant increase in delayed graft function rates (5.4%; 95% CI 23.3% to 7.4%); total in-hospital costs ($2,429; 95% CI $594 to $4.263); and 7-day (2.2%), 14-day (2.6%), and 30-day (2.7%) readmission rates. Policy changes in organ allocation can have a significant impact on perioperative costs and outcomes, which can have a downstream influence on transplantation center perisurgical care processes.

The Impact of the New Kidney Allocation System on Prior Living Kidney Donors' Access to Deceased Donor Kidney Transplants: An Early Look.

This study investigated the early effects of the new kidney allocation system (KAS) on the access of prior living kidney donors (PLDs) to deceased donor kidney transplants. Using data from the Organ Procurement and Transplantation Network, we compared prevalent and incident cohorts of PLDs in the 1-year periods before and after KAS implementation (pre-KAS group: December 4, 2013, to December 3, 2014, n = 50 [newly listed PLDs]; post-KAS group: December 4, 2014, to December 3, 2015, n = 39). We assessed transplant rates per active patient-year, waiting times, and Kidney Donor Profile Index (KDPI) of transplanted kidneys. Transplant rates were not statistically different before and after KAS implementation for either prevalent (2.37 vs. 2.29, relative risk [RR] 0.96; 95% confidence interval [CI] 0.62-1.49) or incident (4.76 vs. 4.36, RR 0.92; 95% CI 0.53-1.60) candidates. Median waiting time (MWT) to deceased donor kidney transplant for prevalent PLDs in the post-KAS cohort was 102.6 days compared with 82.3 days in the pre-KAS cohort (p = 0.98). The median KDPI for PLD recipients was 31% with KAS versus 23% before KAS (p = 0.02). Despite a sharp decrease in the MWT for highly prioritized candidates with calculated panel reactive antibodies of 98-100% (from >7000 to 1164 days), PLDs still had much shorter waiting times (MWT 102.6 days). The new system continues to provide quick access to high-quality organs for PLDs.