Share 35: a liver in time saves lives?

Effect of citizenship status on access to pediatric liver and kidney transplantation

Transplantation of non-US citizen residents remains controversial. We evaluate national trends in transplant activity among pediatric noncitizen residents (PNCR). Pediatric liver and kidney transplant data were obtained from the Organ Procurement and Transplantation Network and the Scientific Registry of Transplant Recipients. Data on transplanted organs, region, waitlist additions, procedures, and citizenship status were analyzed from 2012-2022. Rates of PNCR transplantation activity were compared with population rates from the US Census Bureau. On average, 713 ± 47 pediatric liver and 1039 ± 51 kidney patients were added to the waitlist, with 544 ± 32 liver and 742 ± 33 kidney transplants performed annually. Of these, PNCR comprised 1.5% and 3.3% of liver and kidney waitlist additions and 1.5% and 2.9% of liver and kidney transplant procedures, respectively. There were no significant changes in waitlist or transplant activity nationwide over the study period. There was a significant geographic variation in the percentage of waitlist additions and transplants across the United Network for Organ Sharing regions among the PNCR for liver and kidney transplantation. This is the first study to evaluate national trends in transplantation activity among PNCRs. The significant regional variation in transplantation activity for PNCR may suggest multilevel structural and systemic barriers to transplant accessibility.

Impact of high MELD scores on CMV viremia following liver transplantation

INTRODUCTION

Advanced liver disease or cirrhosis is associated with an increased risk of infections; however, the impact of high pretransplant model for end-stage liver disease (MELD) score on cytomegalovirus (CMV) viremia after liver transplantation is unknown.

METHODS

This single-center, retrospective, cohort study evaluated CMV high-risk (CMV immunoglobulin G D+/R-) liver transplant recipients who received valganciclovir prophylaxis for 3 months between 2009 and 2019. Patients were stratified by pretransplant MELD score of <35 (low MELD) and ≥35 (high MELD). The primary outcome was 12-month CMV viremia, and secondary outcomes included CMV resistance and tissue invasive disease, mortality, biopsy-proven acute rejection (BPAR), leukopenia, and thrombocytopenia. Multivariable Cox proportional-hazards modeling was used to assess the association of MELD score with the time to CMV viremia.

RESULTS

There were 162 and 79 patients in the low and high MELD groups, respectively. Pretransplant MELD score ≥35 was associated with an increased risk of CMV viremia (hazard ratio [HR] 1.73; confidence interval 1.06-2.82, p = .03). CMV viremia occurred at 162 ± 61 days in the low MELD group and 139 ± 62 days in the high MELD group. Although BPAR occurred early at 30 days (13-59) in the low-MELD group and at 18 days (11-66) in the high-MELD group (p = .56), BPAR was not associated with an increased risk of CMV viremia (HR 1.55 [0.93-2.60], p = .1).

DISCUSSION

MELD scores ≥35 were associated with an increased hazards of CMV viremia. In liver transplant recipients with MELD scores ≥35 who are CMV high-risk, additional CMV intervention may be warranted.

Improved Survival With Higher-risk Donor Grafts in Liver Transplant With Acute-on-chronic Liver Failure

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Use of higher-risk grafts in liver transplantation for patients with acute-on-chronic liver failure (ACLF) has been associated with poor outcomes. This study analyzes trends in liver transplantation outcomes for ACLF over time based on the donor risk index (DRI).

Access to liver transplantation for minority populations in the United States

PURPOSE OF REVIEW

Racial disparities in access to liver transplantation have been known since the National Transplant Act of 1980. Since the inception of the Final Rule in 2000, the United Network of Organ Sharing has sought to ensure the equitable distribution of donor livers. Despite several measures aimed to improve access for vulnerable populations, disparities in outcomes are still prevalent throughout the liver transplant (LT) evaluation, while on the waitlist, and after liver transplantation.

RECENT FINDINGS

Blacks and Hispanics are underrepresented on the LT list and have an increased waitlist mortality rate compared to Whites. Additionally, Blacks have a significantly higher risk of posttransplant mortality.

SUMMARY

Ongoing efforts are necessary to eliminate inequities in transplant access. Strategies such as policy implementation and increasing diversity in the healthcare workforce may prove efficacious in creating change.

Disparities in the treatment of hepatocellular carcinoma based on geographical region are decreasing

BACKGROUND AND AIM

Geographic differences have existed in the management of hepatocellular carcinoma (HCC), and efforts to reduce regional disparities have been initiated. The aim of this study is to use the Nationwide Inpatient Sample to determine if regional disparities in the treatment of HCC continue to exist.

METHOD

A retrospective database analysis using the Nationwide Inpatient Sample was performed that included patients with a primary diagnosis of HCC. Logistic regression models were utilized to determine geographic disparities in liver decompensation, treatment, inpatient mortality, and metastatic disease.

RESULTS

This study's locational reach of 62 604 patients included 22 769 patients from the South (36%), 14 554 in the Northeast (23%), 14 041 in the West (22%), and 11 240 in the Midwest (18%). Patients who received treatment in the West were more likely to have inpatient mortality (OR 1.28, 95% CI 1.03, 1.53) than patients who received treatment in the Midwest. No significant differences were observed between rates of resection, ablation, and transarterial chemoembolization when comparing by region. Rates of liver transplantation were lower in the West compared with the Midwest (OR 0.51, 95% CI 0.29, 0.87). There was no significant difference between other regions.

CONCLUSION

Geographic disparities in the treatment of HCC are improving.

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

BACKGROUND & AIMS

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.

METHODS

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.

RESULTS

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 the same score categories 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 (HR 0.365, P < .001).

CONCLUSIONS

Liver allocation based on 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.

Improved retransplant outcomes: early evidence of the share35 impact

BACKGROUND

Share 35 prioritizes offers of deceased donor livers to regional candidates with Model for End-Stage Liver Disease (MELD) ≥35 over local candidates with lower MELD scores. Analysis of Share35 has shown that overall 1- or 2-year post-transplant (LTx) outcomes have been unchanged while waitlist mortality has been reduced. However, these studies exclude retransplant (reLTx) recipients. This study aims to investigate the outcomes of liver retransplants in evaluating the impact of the Share35 policy.

METHODS

A retrospective analysis of data from the United Network for Organ Sharing database over the period June 2011-June 2015 was performed.

RESULTS

A total of 19,748 LTx and 312 reLTx recipients were identified. Of the LTx recipients, 9626 (48.7%) underwent transplant pre-Share 35 and 10,122 (51.3%) post-Share 35. 123 (39.4%) reLTx recipients underwent retransplantation pre-Share 35 and 189 (60.6%) post-Share 35. ReLTx recipients experienced improved 2-year graft survival post-Share 35 compared to pre-Share 35 (67% vs. 21.1%). Patient survival also improved at 2-years for reLTx recipients post-Share 35 compared to pre-Share 35 (69.2% vs. 33.1%). Transplant post-Share 35 was protective for both 2-year graft (HR = 0.669, CI = 0.454-0.985, p = 0.04) and patient (HR = 0.659, CI = 0.44-0.987, p = 0.003) survival.

CONCLUSION

Share35 is associated with improved outcomes after retransplantation.

New Developments in Hepatorenal Syndrome

Hepatorenal syndrome (HRS) continues to be one of the major complications of decompensated cirrhosis, leading to death in the absence of liver transplantation. Challenges in precisely evaluating renal function in the patient with cirrhosis remain because of the limitations of serum creatinine (Cr) alone in estimating glomerular filtration rate (GFR); current GFR estimating models appear to underestimate renal dysfunction. Newer models incorporating renal biomarkers, such as the Cr-Cystatin C GFR Equation for Cirrhosis appear to estimate measured GFR more accurately. A major change in the diagnostic criteria for HRS based on dynamic serial changes in serum Cr that regard HRS type 1 as a special form of acute kidney injury promises the possibility of earlier identification of renal dysfunction in patients with cirrhosis. The diagnostic criteria of HRS still include the exclusion of other causes of kidney injury. Renal biomarkers have been disappointing in assisting with the differentiation of HRS from prerenal azotemia and other kidney disorders. Serum metabolomic profiling may be a more powerful tool to assess renal dysfunction, although the practical clinical significance of this remains unclear. As a result of the difficulties of assessing renal function in cirrhosis and the varying HRS diagnostic criteria and the rigor with which they are applied, the precise incidence and prevalence of HRS is unknown, but it is likely that HRS occurs more commonly than expected. The pathophysiology of HRS is rooted firmly in the setting of progressive reduction in renal blood flow as a result of portal hypertension and splanchnic vasodilation. Progressive marked renal cortical ischemia in patients with cirrhosis parallels the evolution of diuretic-sensitive ascites to diuretic-refractory ascites and HRS, a recognized continuum of renal dysfunction in cirrhosis. Alterations in nitrous oxide production, both increased and decreased, may play a major role in the pathophysiology of this evolution. The inflammatory cascade, triggered by bacterial translocation and endotoxemia, increasingly recognized as important in the manifestation of acute-on-chronic liver failure, also may play a significant role in the pathophysiology of HRS. The mainstay of treatment remains vasopressor therapy with albumin in an attempt to reverse splanchnic vasodilation and improve renal blood flow. Several meta-analyses have confirmed the value of vasopressors, chiefly terlipressin and noradrenaline, in improving renal function and reversing HRS type 1. Other interventions such as renal replacement therapy, transjugular intrahepatic portosystemic shunt, and artificial liver support systems have a very limited role in improving outcomes in HRS. Liver transplantation remains the definitive treatment for HRS. The frequency of simultaneous liver-kidney transplantation has increased dramatically in the Model for End-stage Liver Disease era, with changes in organ allocation policies. This has resulted in a more urgent need to predict native kidney recovery from HRS after liver transplantation alone, to avoid unnecessary simultaneous liver-kidney transplantation.

Improvements in Outcomes for Ethnic Minorities During the Share 35 Era Are Not Due to Decreased Rates of Early Graft Loss

OBJECTIVES

Our aim was to investigate the effects of the Share 35 policy on outcomes in ethnic minorities and recipients who experienced early graft failure.

MATERIALS AND METHODS

We analyzed donor and recipient data from the United Network for Organ Sharing database before (June 6, 2011 to June 18, 2013) and after (June 18, 2013 to June 30, 2015) implementation of Share 35. Graft and patient survival outcomes were compared.

RESULTS

There were significant differences in 1- and 2-year graft and patient survival rates between ethnicities pre-Share 35 (P = .03, P < .001, P = .01, P < .001, respectively). There were no significant differences in 1- and 2-year graft and patient survival between ethnicities post-Share 35 (P = .268, P = .09, P = .343, P = .087, respectively). There were no differences in early graft failure rates pre- and post-Share 35 at 7 days (2.1% vs 2.0; P = .71) and 30 days (4.0% vs 3.8%; P = .47) after transplant, with a decreased early graft failure rate shown at 90 days after transplant (6.8% vs 5.8%; P = .003). When analyzed separately, the low Model for End-Stage Liver Disease (score of < 35) and the high Model for End-Stage Liver Disease recipients (score of ≥ 35) both exhibited reduced early graft failure rates post-Share 35 (6.1% vs 5.3% and 10.8% vs 7.8%, respectively; P < .05).

CONCLUIONS

Share 35 was associated with a short-term reduction in ethnic disparities. Most ethnic groups experienced improved survival in the Share 35 era. Share 35 was not associated with an increase in early graft failure and is an efficacious policy with regard to short-term outcomes.

Same policy, different impact: Center-level effects of share 35 liver allocation

Early studies of national data suggest that the Share 35 allocation policy increased liver transplants without compromising posttransplant outcomes. Changes in center-specific volumes and practice patterns in response to the national policy change are not well characterized. Understanding center-level responses to Share 35 is crucial for optimizing the policy and constructing effective future policy revisions. Data from the United Network for Organ Sharing were analyzed to compare center-level volumes of allocation-Model for End-Stage Liver Disease (aMELD) ≥ 35 transplants before and after policy implementation. There was significant center-level variation in the number and proportion of aMELD ≥ 35 transplants performed from the pre- to post-Share 35 period; 8 centers accounted for 33.7% of the total national increase in aMELD ≥ 35 transplants performed in the 2.5-year post-Share 35 period, whereas 25 centers accounted for 65.0% of the national increase. This trend correlated with increased listing at these centers of patients with Model for End-Stage Liver Disease (MELD) ≥ 35 at the time of initial listing. These centers did not overrepresent the total national volume of liver transplants. Comparison of post-Share 35 aMELD to calculated time-of-transplant (TOT) laboratory MELD scores showed that only 69.6% of patients transplanted with aMELD ≥ 35 maintained a calculated laboratory MELD ≥ 35 at the TOT. In conclusion, Share 35 increased transplantation of aMELD ≥ 35 recipients on a national level, but the policy asymmetrically impacted practice patterns and volumes of a subset of centers. Longer-term data are necessary to assess outcomes at centers with markedly increased volumes of high-MELD transplants after Share 35. Liver Transplantation 23 741-750 2017 AASLD.

Waitlist Outcomes of Liver Transplant Candidates Who Were Reprioritized Under Share 35

Under Share 35, deceased donor (DD) livers are offered regionally to candidates with Model for End-Stage Liver Disease (MELD) scores ≥35 before being offered locally to candidates with MELD scores <35. Using Scientific Registry of Transplant Recipients data from June 2013 to June 2015, we identified 1768 DD livers exported to regional candidates with MELD scores ≥35 who were transplanted at a median MELD score of 39 (interquartile range [IQR] 37-40) with 30-day posttransplant survival of 96%. In total, 1764 (99.8%) exports had an ABO-compatible candidate in the recovering organ procurement organization (OPO), representing 1219 unique reprioritized candidates who would have had priority over the regional candidate under pre-Share 35 allocation. Reprioritized candidates had a median waitlist MELD score of 31 (IQR 27-34) when the liver was exported. Overall, 291 (24%) reprioritized candidates had a comparable MELD score (within 3 points of the regional recipient), and 209 (72%) were eventually transplanted in 11 days (IQR 3-38 days) using a local (50%), regional (50%) or national (<1%) liver; 60 (21%) died, 13 (4.5%) remained on the waitlist and nine (3.1%) were removed for other reasons. Of those eventually transplanted, MELD score did not increase in 57%; it increased by 1-3 points in 37% and by ≥4 points in 5.7% after the export. In three cases, OPOs exchanged regional exports within a 24-h window. The majority of comparable reprioritized candidates were not disadvantaged; however, 21% died after an export.

Liver transplantation after share 35: Impact on pretransplant and posttransplant costs and mortality

Share 35 was implemented in 2013 to direct livers to the most urgent candidates by prioritizing Model for End-Stage Liver Disease (MELD) ≥ 35 patients. We aim to evaluate this policy's impact on costs and mortality. Our study includes 834 wait-listed patients and 338 patients who received deceased donor, solitary liver transplants at Mayo Clinic between January 2010 and December 2014. Of these patients, 101 (30%) underwent transplantation after Share 35. After Share 35, 29 (28.7%) MELD ≥ 35 patients received transplants, as opposed to 46 (19.4%) in the pre-Share 35 era (P = 0.06). No significant difference in 90-day wait-list mortality (P = 0.29) nor 365-day posttransplant mortality (P = 0.68) was found between patients transplanted before or after Share 35. Mean costs were $3,049 (P = 0.30), $5226 (P = 0.18), and $10,826 (P = 0.03) lower post-Share 35 for the 30-, 90-, and 365-day pretransplant periods, and mean costs were $5010 (P = 0.41) and $5859 (P = 0.57) higher, and $9145 (P = 0.54) lower post-Share 35 for the 30-, 90-, and 365-day posttransplant periods. In conclusion, the added cost of transplanting more MELD ≥ 35 patients may be offset by pretransplant care cost reduction. Despite shifting organs to critically ill patients, Share 35 has not impacted mortality significantly. Liver Transplantation 23:11-18 2017 AASLD.

When a liver transplant recipient goes back to alcohol abuse: Should we be more selective?

Alcoholic liver disease (ALD) is one of the most common indications for liver transplantation (LT). However, it has always remained as a complicated topic from both medical and ethical grounds, as it is seen for many a “self-inflicted disease”. Over the years, the survival rate of transplanted patients has significantly improved. The allocation system and the inclusion criteria for LT has also undergone some modifications. Early LT for acute alcoholic hepatitis has been subject to recent clinical studies with encouraging results in highly selected patients. We have learned from studies the importance of a multidisciplinary evaluation of candidates for LT. Complete abstinence should be attempted to overcome addiction issues and to allow spontaneous liver recovery. Risk factors for relapse include the presence of anxiety or depressive disorder, short duration of sobriety pre-LT and lack of social support. The identification of risk factors and the strengthen of social support system may decrease relapse among these patients. Family counseling of candidates is highly encouraged to prevent relapse to alcohol. Relapse has been associated with different histopathological changes, graft damage, graft loss and even decrease in survival among some studies. Therefore, each patient should be carefully selected and priority is to continue to lean on patients with high probability of success. The ethical issue remains as to the patient returning to drinking after the LT, hindering the way for other patients who could have received the same organ.

One Size Does Not Fit All--Regional Variation in the Impact of the Share 35 Liver Allocation Policy

Allocation policies for liver transplantation underwent significant changes in June 2013 with the introduction of Share 35. We aimed to examine the effect of Share 35 on regional variation in posttransplant outcomes. We examined two patient groups from the United Network for Organ Sharing dataset; a pre-Share 35 group composed of patients transplanted between June 17, 2012, and June 17, 2013 (n = 5523), and a post-Share group composed of patients transplanted between June 18, 2013, and June 18, 2014 (n = 5815). We used Kaplan-Meier and Cox multivariable analyses to compare survival. There were significant increases in allocation Model for End-stage Liver Disease (MELD) scores, laboratory MELD scores, and proportions of patients in the intensive care unit and on mechanical, ventilated, or organ-perfusion support at transplant post-Share 35. We also observed a significant increase in donor risk index in this group. We found no difference on a national level in survival between patients transplanted pre-Share 35 and post-Share 35 (p = 0.987). Regionally, however, posttransplantation survival was significantly worse in the post-Share 35 patients in regions 4 and 10 (p = 0.008 and p = 0.04), with no significant differences in the remaining regions. These results suggest that Share 35 has been associated with transplanting "sicker patients" with higher MELD scores, and although no difference in survival is observed on a national level, outcomes appear to be concerning in some regions.