Liver Waitlist Research Articles

Identifying and understanding variation in population-based access to liver transplantation in the United States

We aimed to identify variations in liver transplant access across transplant referral regions (TRRs), accounting for differences in population characteristics and practice environments. Adult end-stage liver disease (ESLD) deaths and liver waitlist additions from 2015 to 2019 were included. The primary outcome was listing-to-death ratio (LDR). We modeled the LDR as a continuous variable and obtained adjusted LDR estimates for each TRR, accounting for clinical and demographic characteristics of ESLD decedents, socioeconomic and health care environment within the TRR, and characteristics of the transplant environment. The overall mean LDR was 0.24 (range: 0.10-0.53). In the final model, proportion of patients living in poverty and concentrated poverty was negatively associated with LDR; organ donation rate was positively associated with LDR. The R2 was 0.60, indicating that 60% of the variability in LDR was explained by the model. Approximately 40% of this variation remained unexplained and may be due to transplant center behaviors amenable to intervention to improve access to care for patients with ESLD.

Association of Body Surface Area With Access to Deceased Donor Liver Transplant and Novel Allocation Policies

Small waitlist candidates are significantly less likely than larger candidates to receive a liver transplant. To investigate the magnitude of the size disparity and test potential policy solutions. A decision analytical model was generated to match liver transplant donors to waitlist candidates based on predefined body surface area (BSA) ratio limits (donor BSA divided by recipient BSA). Participants included adult deceased liver transplant donors and waitlist candidates in the Organ Procurement and Transplantation Network database from June 18, 2013, to March 20, 2020. Data were analyzed from January 2021 to September 2021. Candidates were categorized into 6 groups according to BSA from smallest (group 1) to largest (group 6). Waitlist outcomes were examined. A match run was created for each donor under the current acuity circle liver allocation policy, and the proportion of candidates eligible for a liver based on BSA ratio was calculated. Novel allocation models were then tested. Time on the waitlist, assigned Model for End-Stage Liver Disease (MELD) score, and proportion of patients undergoing a transplant were compared by BSA group. Modeling under the current allocation policies was used to determine baseline access to transplant by group. Simulation of novel allocation policies was performed to examine change in access. There were 41 341 donors (24 842 [60.1%] male and 16 499 [39.9%] female) and 84 201 waitlist candidates (53 724 [63.8%] male and 30 477 [36.2%] female) in the study. The median age of the donors was 42 years (IQR, 28-55) and waitlist candidates, 57 years (IQR, 50-63). Females were overrepresented in the 2 smallest BSA groups (7100 [84.0%] and 7922 [61.1%] in groups 1 and 2, respectively). For each increase in group number, waitlist time decreased (234 days [IQR, 48-700] for group 1 vs 179 days [IQR, 26-503] for group 6; P < .001) and the proportion of the group undergoing transplant likewise improved (3890 [46%] in group 1 vs 4932 [57%] in group 6; P < .001). The smallest 2 groups of candidates were disadvantaged under the current acuity circle allocation model, with 37% and 7.4% fewer livers allocated relative to their proportional representation on the waitlist. Allocation of the smallest 10% of donors (by BSA) to the smallest 15% of candidates overcame this disparity, as did performing split liver transplants. In this study, liver waitlist candidates with the smallest BSAs had a disadvantage due to size. Prioritizing allocation of smaller liver donors to smaller candidates may help overcome this disparity.

Early United States experience with liver donation after circulatory determination of death using thoraco-abdominal normothermic regional perfusion: A multi-institutional observational study.

Mortality on the liver waitlist remains unacceptably high. Donation after circulatory determination of death (DCD) donors are considered marginal but are a potentially underutilized resource. Thoraco-abdominal normothermic perfusion (TA-NRP) in DCD donors might result in higher quality livers and offset waitlist mortality. We retrospectively reviewed outcomes of the first 13 livers transplanted from TA-NRP donors in the US. Nine centers transplanted livers from eight organ procurement organizations. Median donor age was 25 years; median agonal phase was 13 minutes. Median recipient age was 60 years; median lab MELD score was 21. Three patients (23%) met early allograft dysfunction (EAD) criteria. Three received simultaneous liver-kidney transplants; neither had EAD nor delayed renal allograft function. One recipient died 186 days post-transplant from sepsis but had normal presepsis liver function. One patient developed a biliary anastomotic stricture, managed endoscopically; no recipient developed clinical evidence of ischemic cholangiopathy (IC). Twelve of 13 (92%) patients are alive with good liver function at 439 days median follow-up; one patient has extrahepatic recurrent HCC. TA-NRP DCD livers in these recipients all functioned well, particularly with respect to IC, and provide a valuable option to decrease deaths on the waiting list.

Impact of COVID-19 pandemic on the size of US transplant waiting lists.

More patients are waitlisted for solid organs than transplants are performed each year. The COVID-19 pandemic immediately increased waitlist mortality and decreased transplants and listings. To calculate the number of candidate listings after the pandemic began and short-term changes that may affect waiting time, we conducted a Scientific Registry of Transplant Recipients surveillance study from January 1, 2012 to February 28, 2021. The number of candidates on the liver waitlist continued a steady decline that began before the pandemic. Numbers of candidates on the kidney, heart, and lung waitlists decreased dramatically. More than 3000 fewer candidates were awaiting a kidney transplant on March 7, 2021, than on March 8, 2020. Listings and removals decreased for each solid organ beginning in March 2020. The number of heart and lung listings returned to equal or above that of removals. Listings for kidney transplant, which is often less urgent than heart and lung transplant, remain below numbers of removals. Removals due to transplant decreased for all organs, while removals due to death increased for only kidneys. We found no evidence of the predicted surge in listings for solid organ transplant with a plateau or control of the pandemic.

The Precise Relationship Between Model for End-Stage Liver Disease and Survival Without a Liver Transplant.

Scores from the Model for End-Stage Liver Disease (MELD), which are used to prioritize candidates for deceased donor livers, are widely acknowledged to be negatively correlated with the 90-day survival rate without a liver transplant. However, inconsistent and outdated estimates of survival probabilities by MELD preclude useful applications of the MELD score. Using data from all prevalent liver waitlist candidates from 2016 to 2019, we estimated 3-day, 7-day, 14-day, 30-day, and 90-day without-transplant survival probabilities (with confidence intervals) for each MELD score and status 1A. We used an adjusted Kaplan-Meier model to avoid unrealistic assumptions and multiple observations per person instead of just the observation at listing. We found that 90-day without-transplant survival has improved over the last decade, with survival rates increasing >10% (in absolute terms) for some MELD scores. We demonstrated that MELD correctly prioritizes candidates in terms of without-transplant survival probability but that status 1A candidates' short-term without-transplant survival is higher than that of MELD 40 candidates and lower than that of MELD 39 candidates. Our primary result is the updated survival functions themselves. We calculated without-transplant survival probabilities for each MELD score (and status 1A). The survival function is an invaluable tool for many applications in liver transplantation: awarding of exception points, calculating the relative demand for deceased donor livers in different geographic areas, calibrating the pediatric end-stage liver disease score, and deciding whether to accept an offered liver.

New Evidence Supporting Increased Use of Split Liver Transplantation.

Young children and small-statured candidates are dying on liver candidate waitlists. The Organ Procurement and Transplantation Network and United Network for Organ Sharing have proposed a split liver (SL) variance encouraging transplant programs to split more livers to aid these smaller statured candidates. We evaluated the US experience of splitting donor livers during 2002-2016. The results of our analysis provide new evidence to support this variance. During 2002-2016, SL grafts from 935 donors were transplanted into 1870 recipients. Controlling for recipient factors and using time period and program identification as random variables, a multivariable mixed Cox proportional hazards model for graft failure revealed that donor aged 3-10 years had a relative risk (RR) of 3.94 (2.86-5.44), and donor aged >30 years had a RR of 1.94 (1.59-2.35) for graft failure. Donor-to-recipient body surface area ratio <0.90 had a RR of 1.40 (1.13-1.75). Programs with experience transplanting <23 SLs had a RR of 1.43 (1.21-1.75). The same program transplanting both split segments had a RR of 1.38 (1.20-1.59). Splitting protocols based on these findings could improve graft survival after SL transplantation, which would encourage programs to opt into splitting more livers. The new protocols may consider donor age restrictions, necessary program experience, donor with body surface area appropriate for recipient, and improved logistical factors to share segments between transplant programs. The result would likely be a drastic reduction in liver waitlist deaths for young children and small-statured candidates.

Regional Variation in Appropriateness of Non-Hepatocellular Carcinoma Model for End-Stage Liver Disease Exception

Patients thought to be at greater risk of liver waitlist dropout than their laboratory Model for End-Stage Liver Disease (lMELD) score reflects are commonly given MELD exceptions, where a higher allocation MELD (aMELD) score is assigned that is thought to reflect the patient's risk. This study was undertaken to determine whether exceptions for reasons other than hepatocellular carcinoma (HCC) are justified, and whether exception aMELD scores appropriately estimate risk. Adult primary liver transplantation candidates listed in the current era of liver allocation in the United Network for Organ Sharing database were analyzed. Patients granted non-HCC-related MELD exceptions and those without MELD exceptions were compared. Rates of waitlist dropout and liver transplantation were analyzed using cause-specific hazards regression, with separate models fitted to adjust for lMELD and aMELD. There were 29,243 patients, with 2,555 in the exception group. Nationally, exception patients were more likely to dropout (hazard ratio [HR] 1.60; 95% CI, 1.45 to 1.76; p < 0.001) or undergo liver transplantation (HR 3.49; 95% CI, 3.32 to 3.67; p < 0.001) than their lMELD-adjusted counterparts. Adjusting for aMELD, exception patients were less likely to dropout (HR 0.77; 95% CI, 0.70 to 0.85; p < 0.001) and less likely to undergo liver transplantation (HR 0.76; 95% CI, 0.72 to 0.80; p < 0.001). Exception patients were not at significantly increased risk of waitlist dropout when adjusted for lMELD in 4 of 11 United Network for Organ Sharing regions. Despite appropriate use of non-HCC MELD exceptions on a national level, patients with non-HCC MELD exceptions were awarded inappropriately high priority for transplantation in many regions. This highlights the need to consider local conditions faced by transplantation candidates when estimating waitlist mortality and determining priority for transplantation.

How Does Treating Chronic Hepatitis C Affect Individuals in Need of Organ Transplants in the United Kingdom?

ObjectivesTo estimate the impact of cures for chronic hepatitis C (CHC) infection on organ donation in the United Kingdom. Curing CHC infection reduces the need for liver transplants and enables cured individuals to donate organs of all types. MethodsWe adapted a double-queuing model of organ allocation to estimate the effects of CHC infection cures on liver, lung, heart, and kidney transplants in the United Kingdom. We assumed that cured individuals would donate organs at similar rates as the general population and no longer require liver transplants because of CHC infection. We estimated how curing CHC infection influences waitlist lengths for each organ and the annual net present value to society on the basis of quality-adjusted life-years gained through additional transplants under opt-in and opt-out organ donation policies. ResultsCuring CHC generates the most value for patients on the liver waitlist, because it increases the number of transplantable livers and reduces the need for transplants. Under the current opt-in policy, liver waitlist length falls by 24%, generating £34.3 million of annual net present value. Growth in the number of uninfected lungs, hearts, and kidneys generates an additional £19.2 million annually, with £18.7 million from kidneys. Implementing the opt-out policy, liver waitlist length would decrease by 75%, implying that treating CHC eliminates one-third of the excess liver waitlist due to an opt-in policy. ConclusionsTreating CHC has large positive spillovers to uninfected individuals by reducing the need for liver transplants and allowing cured individuals to donate organs. These spillovers have not been included in traditional value assessments of CHC treatment.

Factors Associated with Survival of Patients With Severe Acute-On-Chronic Liver Failure Before and After Liver Transplantation

Liver transplantation for patients with acute-on-chronic liver failure (ACLF) with 3 or more failing organs (ACLF-3) is controversial. We compared liver waitlist mortality or removal according to model for end-stage liver disease (MELD) score vs ACLF category. We also studied factors associated with reduced odds of survival for 1 year after liver transplantation in patients with ACLF-3. We analyzed data from the United Network for Organ Sharing (UNOS) from 2005 through 2016. We identified patients who were on the waitlist (100,594) and those who received liver transplants (50,552). Patients with ACLF were identified based on the European Association for the Study of the Liver-chronic liver failure criteria. Outcomes were evaluated with competing risks regression, Kaplan-Meier analysis, and Cox proportional hazards regression. Patients with ACLF-3 were more likely to die or be removed from the waitlist, regardless of MELD-sodium (MELD-Na) score, compared with the other ACLF groups; the proportion was greatest for patients with an ACLF-3 score and MELD-Na score below 25 (43.8% at 28 days). Mechanical ventilation at liver transplantation (hazard ratio [HR] 1.49; 95% confidence interval [CI] 1.22-1.84), donor risk index above 1.7 (HR 1.22; 95% CI 1.09-1.35), and liver transplantation within 30 days of listing (HR 0.89; 95% CI 0.81-0.98) were independently associated with survival for 1 year after liver transplantation CONCLUSIONS: In an analysis of datafrom the UNOS registry, we found high mortality among patients with ACLF-3 on the liver transplant waitlist, even among those with lower MELD-Na scores. So, certain patients with ACLF-3 have poor outcomes regardless of MELD-Na score. Livertransplantation increases odds of survival for these patients, particularly if performed within 30 days of placement on the waitlist. Mechanical ventilation at liver transplantation and use of marginal organs were associated with increased risk of death.

Liver transplantation and waitlist mortality for HCC and non-HCC candidates following the 2015 HCC exception policy change.

Historically, exception points for hepatocellular carcinoma (HCC) led to higher transplant rates and lower waitlist mortality for HCC candidates compared to non-HCC candidates. As of October 2015, HCC candidates must wait 6months after initial application to obtain exception points; the impact of this policy remains unstudied. Using 2013-2017 SRTR data, we identified 39 350 adult, first-time, active waitlist candidates and compared deceased donor liver transplant (DDLT) rates and waitlist mortality/dropout for HCC versus non-HCC candidates before (October 8, 2013-October 7, 2015, prepolicy) and after (October 8, 2015-October 7, 2017, postpolicy) the policy change using Cox and competing risks regression, respectively. Compared to non-HCC candidates with the same calculated MELD, HCC candidates had a 3.6-fold higher rate of DDLT prepolicy (aHR=3.49 3.69 3.89 ) and a 2.2-fold higher rate of DDLT postpolicy (aHR=2.09 2.21 2.34 ). Compared to non-HCC candidates with the same allocation priority, HCC candidates had a 37% lower risk of waitlist mortality/dropout prepolicy (asHR=0.54 0.63 0.73 ) and a comparable risk of mortality/dropout postpolicy (asHR=0.81 0.95 1.11 ). Following the policy change, the DDLT advantage for HCC candidates remained, albeit dramatically attenuated, without any substantial increase in waitlist mortality/dropout. In the context of sickest-first liver allocation, the revised policy seems to have established allocation equity for HCC and non-HCC candidates.

Effects of Allocating Livers for Transplantation Based on Model for End-Stage Liver Disease–Sodium Scores on Patient Outcomes

The Model for End-stage Liver Disease and Sodium (MELD-Na) score was introduced for liver allocation in January 2016. We evaluated the effects of liver allocation, based on MELD-Na score, on waitlist and post-transplantation outcomes. We examined 2 patient groups from the United Network for Organ Sharing registry; the MELD-period group was composed of patients who were registered as transplant candidates from June 18, 2013 through January 10, 2016 (n= 18,850) and the MELD-Na period group was composed of patients who were registered from January 11, 2016 through September 30, 2017 (n= 14,512). We compared waitlist and post-transplantation outcomes and association with serum sodium concentrations between groups. Mortality within 90 days on the liver waitlist decreased (hazard ratio [HR] 0.738, P < .001) and transplantation probability increased significantly (HR 1.217, P < .001) in the MELD-Na period. Although mild, moderate, and severe hyponatremia (130-134, 125-129, and <125 mmol/L) were independent risk factors for waitlist mortality in the MELD period (HR 1.354, 1.762, and 2.656; P< .001, P < .001, and P < .001, respectively) compared with the reference standard (135-145 mmol/L), these adverse outcomes were decreased in the MELD-Na period (HR 1.092, 1.271 and 1.374; P= .27, P= .018, and P= .037, respectively). The adjusted survival benefit of transplant recipients vs patients placed on the waitlist in thesame scorecategories was definitive for patients with MELD-Na scores of 21-23 in the MELD-Na era (HR 0.336, P<.001) compared with MELD scores of 15-17 in the MELD era (HR0.365, P < .001). Liver allocation basedon MELD-Na score successfully improved waitlist outcomes and provided significant benefit to hyponatremic patients. Given the discrepancy in transplantation survival benefit, the current rules for liver allocation might require revision.

Outcomes from Livers Transplanted from Deceased Donors with End-Stage Renal Disease

Introduction Decedents with end-stage renal disease (ESRD) have comorbidities that also impact the quality of extra-renal, especially thoracic, organs. Livers, however, are less susceptible to ESRD-associated damage, yet many organ procurement organizations (OPOs) in the United States have not pursued such donors because of financial and regulatory disincentives. Because of the high liver waitlist mortality, however, all usable livers should be transplanted. No data are published on the outcomes of livers transplanted from deceased donors with ESRD; if outcomes are acceptable, financial disincentives must be addressed. We describe the outcomes of livers retrieved from donors with ESRD in a single OPO. Methods Donors (n=47) with ESRD who donated livers from January 2010-May 2017 were identified in a prospective database; relevant variables were extracted into a separate database analyzed with Stata. Our primary aim was to determine graft and patient survival; these data were obtained from TEIDI and from the transplant centers. Results 47 livers were retrieved and transplanted from ESRD donors. Mean time on dialysis was 3.3 years (range 1 month to 13 years). Causes of death included CVA (n=24), anoxia (n=19), trauma (n=3), other (n=1). Two recipients died within 30 days (hemorrhage, day 19; multisystem organ failure, day 23); one patient was retransplanted on day 14 (unknown cause of graft loss). All other patients (95.8%) and grafts (93.6%) survived more than 30 days (Figure 1). Interestingly, livers exported out of our service area (n=14) had significantly better survival than those transplanted locally (Figure 2). No other variable analyzed impacted graft survival. Ischemic times ranged from 2.2 to 10. 6 (mean = 6.0) hours were similar between exported and locally transplanted livers – mean = 6.4 and 5.9 hours, respectively, p=0.813.Conclusions Livers from donors with ESRD can be transplanted with excellent outcomes, especially in circumstances where short ischemic times can be achieved. Given the high liver waitlist mortality worldwide, these donors should be aggressively pursued. Financial and regulatory disincentives must be eliminated in order to increase the number of livers retrieved and transplanted.

Access to Liver Transplantation in Different ABO-Blood Groups and “Exceptions Points” in a Model for End-Stage Liver Disease Allocation System: A Brazilian Single-Center Study

BackgroundIn the Model for End-Stage Liver Disease (MELD) system, patients with “MELD exceptions” points may have unfair privilege in the competition for liver grafts. Furthermore, organ distribution following identical ABO blood types may also result in unjust organ allocation. The aim of this study was to investigate access to liver transplantation in a tertiary Brazilian center, regarding “MELD exceptions” situations and among ABO-blood groups. MethodsA total of 465 adult patients on the liver waitlist from August 2015 to August 2016 were followed up until August 2017. Patients were divided into groups according to ABO-blood type and presence of “exceptions points.” ResultsNo differences in outcomes were observed among ABO-blood groups. However, patients from B and AB blood types spent less time on the list than patients from A and O groups (median, 46, 176, 415, and 401 days, respectively; P = .03). “Exceptions points” were granted for 141 patients (30.1%), hepatocellular carcinoma being the most common reason (52.4%). Patients with “exceptions points” showed higher transplantation rate, lower mortality on the list, and lower delta-MELD than non-exceptions patients (56.7% vs 19.1% [P < .01]; 18.4% vs 38.5% [P < .01], and 2.0 ± 2.6 vs 6.9 ± 7.0 [P < .01], respectively). Patients with refractory ascites had a higher mortality rate than those with other “exceptions” or without (48%). ConclusionsThe MELD system provides equal access to liver transplantation among ABO-blood types, despite shorter time on the waitlist for AB and B groups. The current MELD exception system provides advantages for candidates with “exception points,” resulting in superior outcomes compared with those without exceptions.

A liver for a kidney: Ethics of trans-organ paired exchange.

Living donation provides important access to organ transplantation, which is the optimal therapy for patients with end-stage liver or kidney failure. Paired exchanges have facilitated thousands of kidney transplants and enable transplantation when the donor and recipient are incompatible. However, frequently willing and otherwise healthy donors have contraindications to the donation of the organ that their recipient needs. Trans-organ paired exchanges would enable a donor associated with a kidney recipient to donate a lobe of liver and a donor associated with a liver recipient to donate a kidney. This article explores some of the ethical concerns that trans-organ exchange might encounter including unbalanced donor risks, the validity of informed consent, and effects on deceased organ donation.

Role of Patient Factors and Practice Patterns in Determining Access to Liver Waitlist

Geographic variability in access to care is a persistent challenge in transplantation. Little is known about how patients with end-stage liver disease are chosen for referral, evaluation and listing. Utilizing death certificate data from the Centers for Disease Control and Prevention from 2002 to 2009, estimated liver demand (ELD) was measured by aggregating annual deaths from liver disease and liver transplants performed in each donor service area (DSA). In DSAs with higher ELD, more patients per capita were listed for transplantation (p < 0.001). In addition, listing rates per ELD varied fivefold across DSAs, with more patients per ELD being transplanted in DSAs with higher listing rates (p < 0.001). After adjusting for liver donor risk index and MELD at transplant, there was no association between listing rate and posttransplant survival (HR 1.002, p = 0.77). In addition, DSAs with lower listing rates were more likely to export organs (p < 0.001) of lower liver donor risk index (p < 0.001). Listing sicker patients was associated with increased access to the waitlist and transplantation and more efficient organ utilization, but had minimal effect on posttransplant outcomes after adjusting for the resulting organ shortage.

Early Changes in Liver Distribution Following Implementation of Share 35

In June 2013, a change to the liver waitlist priority algorithm was implemented. Under Share 35, regional candidates with MELD ≥ 35 receive higher priority than local candidates with MELD < 35. We compared liver distribution and mortality in the first 12 months of Share 35 to an equivalent time period before. Under Share 35, new listings with MELD ≥ 35 increased slightly from 752 (9.2% of listings) to 820 (9.7%, p = 0.3), but the proportion of deceased-donor liver transplants (DDLTs) allocated to recipients with MELD ≥ 35 increased from 23.1% to 30.1% (p < 0.001). The proportion of regional shares increased from 18.9% to 30.4% (p < 0.001). Sharing of exports was less clustered among a handful of centers (Gini coefficient decreased from 0.49 to 0.34), but there was no evidence of change in CIT (p = 0.8). Total adult DDLT volume increased from 4133 to 4369, and adjusted odds of discard decreased by 14% (p = 0.03). Waitlist mortality decreased by 30% among patients with baseline MELD > 30 (SHR = 0.70, p < 0.001) with no change for patients with lower baseline MELD (p = 0.9). Posttransplant length-of-stay (p = 0.2) and posttransplant mortality (p = 0.9) remained unchanged. In the first 12 months, Share 35 was associated with more transplants, fewer discards, and lower waitlist mortality, but not at the expense of CIT or early posttransplant outcomes.

Heterogeneity and Disparities in the Use of Exception Scores in Pediatric Liver Allocation

Physicians apply for Model for End-Stage Liver Disease/Pediatric End-Stage Liver Disease exception points on a case-by-case basis to improve an individual patient's chances of receiving a liver transplant. This retrospective cohort study describes trends in the use of exceptions among the pediatric liver waitlist population with chronic liver disease. The cohort (n = 3728) included all children with a diagnosis of chronic liver disease listed in the United Network for Organ Sharing transplant database for first isolated liver transplant between February 27, 2002 and March 31, 2013. Exception score requests were common (34%); 90% of requests were approved. The rate of exception score requests in 2013 was five times that of 2002 (incident rate ratios [IRR] 5.25, 95% confidence interval [CI] 3.19-8.63, p < 0.01). Patients of non-White race had exception score request rates 13% lower than patients of White race (IRR 0.87, 95% CI 0.77-0.98, p = 0.02). Older patients had lower rates of exception score requests than younger patients (p = 0.03). Request rates varied by region. Time spent at an active exception status nearly tripled the hazard rate for transplantation (hazard ratio = 2.90, 95% CI 2.62-3.21, p < 0.01). There is disparity in use of exceptions by race that is not explained by clinical disease severity, diagnosis, geography or other demographic factors.

OPTN/SRTR 2013 Annual Data Report: liver.

During 2013, 10,479 adult candidates were added to the liver transplant waiting list, compared with 10,185 in 2012; 5921 liver transplants were performed, and 211 of the transplanted organs were from living donors. As of December 31, 2013, 15,027 candidates were registered on the waiting list, including 12,407 in active status. The most significant change in allocation policy affecting liver waitlist trends in 2013 was the Share 35 policy, whereby organs from an entire region are available to candidates with model for end-stage liver disease scores of 35 or higher. Median waiting time for such candidates decreased dramatically, from 14.0 months in 2012 to 1.4 months in 2013, but the effect on waitlist mortality is unknown. The number of new active pediatric candidates added to the liver transplant waiting list increased to 693 in 2013. Transplant rates were highest for candidates aged younger than 1 year (275.6 per 100 waitlist years) and lowest for candidates aged 11 to 17 years (97.0 per 100 waitlist years). Five-year graft survival was 71.7% for recipients aged younger than 1 year, 74.9% for ages 1 to 5 years, 78.9% ages 6 to 10 years, and 77.4% for ages 11 to 17 years.

Higher Mortality in Patients With Sudden MELD Increase: Disadvantaged By the Current Allocation Policy.

Priority of allocation on the deceased donor liver waitlist is based on current MELD; ties are broken by waiting time accrued at a current or higher MELD value. However, registrants whose MELD has recently increased may be at higher, not lower, mortality risk. We modeled 7-day mortality risk in 67141 adult liver waitlist registrants from 2002-2013 using logistic regression. Using a likelihood maximization procedure, we defined a MELD “spike” as a MELD increase of at least 30% over the previous 7 days. 38.9% of patients had at least one spike while on the liver waitlist. Registrants with a spike in the previous 7 days had higher risk of mortality in the following 7 days than registrants at the same current MELD with no spike (Figure 1A). The additional risk of death conferred by a spike was equivalent to 2-9 additional MELD points depending on current MELD: specifically, a registrant with a spike and a MELD of 10, 20, or 30 had mortality risk equivalent to those with a MELD of 18, 26, or 34 and no spike. Risk increase associated with a spike was highest for patients with low MELD scores (Figure 1B): specifically, 3.77-fold (3.59 - 3.95), 2.42-fold (2.35 - 2.49), 1.55-fold (1.51 - 1.60) higher odds of 7-day mortality at MELD of 15, 25, and 35.Figure: No Caption available.Figure: No Caption available.In a calibration plot (Figure 2) of predictive validity among patients with a recent MELD spike, predicted mortality risk from a model (model 1) with no spike was consistently less than observed risk, while predicted mortality risk from a model (model 2) incorporating spike matched observed risk more closely.Figure: No Caption available.Registrants with a recent sudden MELD increase have higher risk of short-term mortality than indicated by their current MELD. As such, allocation policy should be adjusted to reflect this risk.

Impact of Donor Hepatitis C Virus Infection Status on Death and Need for Liver Transplant in Hepatitis C Virus–Positive Kidney Transplant Recipients

Only 29% of deceased donor kidney recipients with hepatitis C virus (HCV) receive HCV-positive (HCV+) kidneys. These kidneys are discarded 2.5 times more often than their HCV-negative (HCV-) counterparts, possibly due to the sense that an HCV+ kidney may adversely affect recipient liver function. The goals of this study were to characterize liver disease in HCV+ kidney recipients and compare rates of liver-related outcomes by kidney donor HCV status. Observational cohort study. 6,250 patients with HCV who had a kidney transplant in 1995-2008 as captured in the United Network for Organ Sharing (UNOS) database. Liver-related outcomes were assessed by cross-linking with the liver waitlist and transplant data sets. HCV status of transplanted kidney. Joining the liver waitlist, receiving a liver transplant, death. Time to event. Only 63 (1%) of HCV+ kidney recipients eventually joined the liver waitlist during the 13-year study period. Those who received HCV+ kidneys had a 2.6-fold higher hazard of joining the liver list (P < 0.001); however, the absolute difference in rate of listing between recipients of HCV- and HCV+ kidneys was <2%. This is consistent with findings of only 2% lower patient survival at 3 years in HCV+ patients receiving HCV+ versus HCV- kidneys. We lacked data for HCV viral load and genotype of both HCV+ recipients and transplanted HCV+ kidneys. Because transplant with an HCV+ kidney may reduce waiting-time by more than a year for an HCV+ patient and there is a high risk of kidney waitlist mortality, a 2% increased rate of adverse liver outcomes and 2% increased rate of death at 3 years should not universally preclude the use of HCV+ kidneys when the intended recipient is also HCV+.