18 Month Review of Liver Acuity Circles Allocation

Purpose: Acuity circles (AC) allocation was implemented on 2/4/2020 with a goal of removing DSA and region from liver allocation and broadening the distribution of livers, particularly for highly medically urgent candidates. Method(s): OPTN waitlist and transplant data was analyzed 18 months pre- (8/6/2018- 2/3/2020) and post- (2/4/2020-8/3/2021) AC implementation. Result(s): Post-policy, there were 448 more adult (age 18+ at listing) and 83 less pediatric (<18 at listing) waitlist additions, 570 more adult (age 18+ at transplant) and 4 less pediatric (<18 at transplant) deceased donor liver-alone transplants, and 121 less adult and 12 less pediatric removals for death or too sick. Transplant rates significantly increased overall post-policy, notably in the most medically urgent groups (Figure 1). The national median transplant score for adults remained unchanged at 28 and decreased from 35 to 30 for pediatric transplant recipients, likely due to the increased number of adolescents (age 12-17) transplanted at MELD scores under 29. There was a noticeable shift in the distribution of distance between donor hospital and transplant program, particularly for the most medically urgent groups where larger proportions of livers are coming from 250-500 NMs (Figure 2). Despite this change, median cold ischemia time increased only 11 minutes for adult recipients and 33 minutes for pediatric recipients post-policy. One year post transplant patient survival decreased from 94% pre-policy to 93% post-policy (p=0.02). Conclusion(s): Broader allocation increased transplant rates and livers are traveling longer distances for candidates with greater medical urgency with little effect on cold ischemia time and post-transplant survival. Unfortunately, AC implementation was followed shortly by COVID-19 making it difficult to parse out COVID-19 from potential policy effects. Metrics will continue to be monitored as more data become available. (Figure Presented).

OPTN/SRTR 2020 Annual Data Report: Liver.

This year was marked by the COVID-19 pandemic, which altered transplant program activity and affected waitlist and transplant outcomes. Still, 8906 liver transplants were performed, an all-time high, across 142 centers in the United States, and pretransplant as well as graft and patient survival metrics, continued to improve. Living donation activity decreased after several years of growth. As of June 30, 2020, 98989 liver transplant recipients were alive with a functioning graft, and in the context of increasing liver transplant volume, the size of both the adult and pediatric liver transplant waitlists have decreased. On February 4, 2020, shortly before the pandemic began, a new liver distribution policy based on acuity circles was implemented, replacing donor service area- and region-based boundaries. A policy change to direct pediatric livers to pediatric recipients led to an increase in deceased donor transplant rates and a decrease in pretransplant mortality rate among children, although the absolute number of pediatric transplants did not increase in 2020. Among adults, alcohol-associated liver disease became the predominant indication for liver transplant in 2020. After implementation of the National Liver Review Board and lower waitlist priority for most exception cases in 2019, fewer liver transplants were being performed via exception points, and the transplant rate between those with and without hepatocellular carcinoma has equalized. Women continue to experience higher pretransplant mortality and lower rates of liver transplant than men.

The effect of acuity circles on deceased donor transplant and offer rates across meld and exception statuses

Purpose: Acuity circles (AC) allocation was implemented on February 4, 2020. AC significantly changed the relative priority of candidates with allocation PELD/ MELD scores of 29 to 34. We therefore performed a difference-in-differences analysis for the effect of AC on adjusted deceased donor transplant and offer rates across PELD/MELD categories. Methods: The before-AC period was February 4, 2019 to February 3, 2020, and the after-AC period was February 4 to March 12, 2020, the day before the national declaration of emergency due to COVID-19. Deceased donor transplant rates used active candidate time on the waiting list during the study period. The deceased donor offer rate was the number of offers in the first 10 spots of match run a candidate received per person-year. Only offers before the final acceptance were included. Transplant and offer rates were adjusted for other candidate characteristics. Results: Candidates with PELD/MELD 29-32 and PELD/MELD 33-36 had larger differences in transplant rates before and after AC than candidates with PELD/MELD 15-28, while other PELD/MELD categories also had larger but non-significant dif Admin ferences compared to candidates with PELD/MELD 15-28 (Figure 1). In contrast, all candidates with PELD/MELD 29 and higher had dramatically larger offers rates before and after AC than candidates with PELD/MELD 15-28 (Figure 2). Conclusions: Taken together, the implementation of AC increased the relative access to deceased donor transplant for candidates with PELD/MELD of 29-36 without reducing access for candidates with higher allocation priority.

Early review of liver acuity circles allocation

Purpose: Acuity circles (AC) allocation was implemented on February 4, 2020, followed shortly by the declaration of national emergency for COVID-19. The goal of this policy was to broaden distribution of livers, particularly for highly medically urgent candidates. Methods: OPTN liver waitlist, transplant, and donor data were used. Cohorts of deceased donor liver-alone transplants for the pre- (2/5 - 7/2/2019) and post-eras (2/4 - 6/30/2020), as well as cohorts of liver waitlist registrations added, liver-alone waitlist registrations removed due to death or too sick to transplant, and deceased liver donors during 2/5 - 8/6/2019 (pre-policy) and 2/4 - 8/4/2020 (post-policy) were assessed. Results: Similar volumes of deceased liver donors were recovered pre- and postpolicy (4545 vs. 4564). While 375 fewer new registrations were added to the liver waitlist post-policy largely due to COVID-19, similar numbers of registration removals occurred (1093 pre- vs. 1020 post-policy) (Figure 1). There were fewer transplants overall post-policy (2997 vs. 3140 pre), with similar proportions of recipients with MELD or PELD scores of 29 and higher (51.7% pre- vs. 51.2% post-policy). However, these most medically urgent recipients received livers from farther away post-policy (Figure 2). The variation in median allocation score at transplant, as a measure of disparity across areas, has also decreased by most geographic units (Figure 3). Conclusions: It can already be seen that livers are being more broadly distributed for those with greater medical urgency, and geographic disparities are decreasing. However, the confounding effects of COVID-19 cannot be parsed out from potential policy effects, and continued data accumulation and monitoring of the system by the OPTN Liver Committee will be needed to determine the true effects of this policy change. (Table Presented).