MELD 3.0: The Model for End-Stage Liver Disease Updated for the Modern Era

BACKGROUND & AIMS

The Model for End-Stage Liver Disease (MELD) has been established as a reliable indicator of short-term survival in patients with end-stage liver disease. The current version (MELDNa), consisting of the international normalized ratio and serum bilirubin, creatinine, and sodium, has been used to determine organ allocation priorities for liver transplantation in the United States. The objective was to optimize MELD further by taking into account additional variables and updating coefficients with contemporary data.

METHODS

All candidates registered on the liver transplant wait list in the US national registry from January 2016 through December 2018 were included. Uni- and multivariable Cox models were developed to predict survival up to 90 days after wait list registration. Model fit was tested using the concordance statistic (C-statistic) and reclassification, and the Liver Simulated Allocation Model was used to estimate the impact of replacing MELDNa with the new model.

RESULTS

The final multivariable model was characterized by (1) additional variables of female sex and serum albumin, (2) interactions between bilirubin and sodium and between albumin and creatinine, and (3) an upper bound for creatinine at 3.0 mg/dL. The final model (MELD 3.0) had better discrimination than MELDNa (C-statistic, 0.869 vs 0.862; P < .01). Importantly, MELD 3.0 correctly reclassified a net of 8.8% of decedents to a higher MELD tier, affording them a meaningfully higher chance of transplantation, particularly in women. In the Liver Simulated Allocation Model analysis, MELD 3.0 resulted in fewer wait list deaths compared to MELDNa (7788 vs 7850; P = .02).

CONCLUSION

MELD 3.0 affords more accurate mortality prediction in general than MELDNa and addresses determinants of wait list outcomes, including the sex disparity.

COVID-19-related mortality in kidney transplant and dialysis patients: results of the ERACODA collaboration

BACKGROUND

Patients on kidney replacement therapy comprise a vulnerable population and may be at increased risk of death from coronavirus disease 2019 (COVID-19). Currently, only limited data are available on outcomes in this patient population.

METHODS

We set up the ERACODA (European Renal Association COVID-19 Database) database, which is specifically designed to prospectively collect detailed data on kidney transplant and dialysis patients with COVID-19. For this analysis, patients were included who presented between 1 February and 1 May 2020 and had complete information available on the primary outcome parameter, 28-day mortality.

RESULTS

Of the 1073 patients enrolled, 305 (28%) were kidney transplant and 768 (72%) dialysis patients with a mean age of 60 ± 13 and 67 ± 14 years, respectively. The 28-day probability of death was 21.3% [95% confidence interval (95% CI) 14.3-30.2%] in kidney transplant and 25.0% (95% CI 20.2-30.0%) in dialysis patients. Mortality was primarily associated with advanced age in kidney transplant patients, and with age and frailty in dialysis patients. After adjusting for sex, age and frailty, in-hospital mortality did not significantly differ between transplant and dialysis patients [hazard ratio (HR) 0.81, 95% CI 0.59-1.10, P = 0.18]. In the subset of dialysis patients who were a candidate for transplantation (n = 148), 8 patients died within 28 days, as compared with 7 deaths in 23 patients who underwent a kidney transplantation <1 year before presentation (HR adjusted for sex, age and frailty 0.20, 95% CI 0.07-0.56, P < 0.01).

CONCLUSIONS

The 28-day case-fatality rate is high in patients on kidney replacement therapy with COVID-19 and is primarily driven by the risk factors age and frailty. Furthermore, in the first year after kidney transplantation, patients may be at increased risk of COVID-19-related mortality as compared with dialysis patients on the waiting list for transplantation. This information is important in guiding clinical decision-making, and for informing the public and healthcare authorities on the COVID-19-related mortality risk in kidney transplant and dialysis patients.

Frailty Associated With Waitlist Mortality Independent of Ascites and Hepatic Encephalopathy in a Multicenter Study

BACKGROUND & AIMS

Frailty is associated with mortality in patients with cirrhosis. We measured frailty using 3 simple tests and calculated Liver Frailty Index (LFI) scores for patients at multiple ambulatory centers. We investigated associations between LFI scores, ascites, and hepatic encephalopathy (HE) and mortality.

METHODS

Adults without hepatocellular carcinoma who were on the liver transplantation waitlist at 9 centers in the United States (N = 1044) were evaluated using the LFI; LFI scores of at least 4.5 indicated that patients were frail. We performed logistic regression analyses to assess associations between frailty and ascites or HE and competing risk regression analyses (with liver transplantation as the competing risk) to estimate sub-hazard ratios (sHRs) of waitlist mortality (death or removal from the waitlist).

RESULTS

Of study subjects, 36% had ascites, 41% had HE, and 25% were frail. The odds of frailty were higher for patients with ascites (adjusted odd ratio 1.56, 95% confidence interval [CI] 1.15-2.14) or HE (odd ratio 2.45, 95% CI 1.80-3.33) than for those without these features. Larger proportions of frail patients with ascites (29%) or HE (30%) died while on the waitlist compared with patients who were not frail (17% of patients with ascites and 20% with HE). In univariable analysis, ascites (sHR 1.52, 95% CI 1.14-2.05), HE (sHR 1.84, 95% CI 1.38-2.45), and frailty (sHR 2.38, 95% CI 1.77-3.20) were associated with waitlist mortality. In adjusted models, only frailty remained significantly associated with waitlist mortality (sHR 1.82, 95% CI 1.31-2.52); ascites and HE were not.

CONCLUSIONS

Frailty is a prevalent complication of cirrhosis that is observed more frequently in patients with ascites or HE and independently associated with waitlist mortality. LFI scores can be used to objectively quantify risk of death related to frailty-in excess of liver disease severity-in patients with cirrhosis.

Liver Transplantation for Hepatocellular Carcinoma. Working Group Report from the ILTS Transplant Oncology Consensus Conference

Liver transplantation (LT) offers excellent long-term outcome for certain patients with hepatocellular carcinoma (HCC), with a push to not simply rely on tumor size and number. Selection criteria should also consider tumor biology (including alpha-fetoprotein), probability of waitlist and post-LT survival (ie, transplant benefit), organ availability, and waitlist composition. These criteria may be expanded for live donor LT (LDLT) compared to deceased donor LT though this should not adversely affect the double equipoise in LDLT, namely ensuring both acceptable recipient outcomes and donor safety. HCC patients with compensated liver disease and minimal tumor burden have low urgency for LT, especially after local-regional therapy with complete response, and do not appear to derive the same benefit from LT as other waitlist candidates. These guidelines were developed to assist in selecting appropriate HCC patients for both deceased donor LT and LDLT.

Liver transplant recipient survival benefit with living donation in the model for endstage liver disease allocation era

Receipt of a living donor liver transplant (LDLT) has been associated with improved survival compared with waiting for a deceased donor liver transplant (DDLT). However, the survival benefit of liver transplant has been questioned for candidates with Model for Endstage Liver Disease (MELD) scores <15, and the survival advantage of LDLT has not been demonstrated during the MELD allocation era, especially for low MELD patients. Transplant candidates enrolled in the Adult-to-Adult Living Donor Liver Transplantation Cohort Study after February 28, 2002 were followed for a median of 4.6 years. Starting at the time of presentation of the first potential living donor, mortality for LDLT recipients was compared to mortality for patients who remained on the waiting list or received DDLT (no LDLT group) according to categories of MELD score (<15 or ≥ 15) and diagnosis of hepatocellular carcinoma (HCC). Of 868 potential LDLT recipients (453 with MELD <15; 415 with MELD ≥ 15 at entry), 712 underwent transplantation (406 LDLT; 306 DDLT), 83 died without transplant, and 73 were alive without transplant at last follow-up. Overall, LDLT recipients had 56% lower mortality (hazard ratio [HR] = 0.44, 95% confidence interval [CI] 0.32-0.60; P < 0.0001). Among candidates without HCC, mortality benefit was seen both with MELD <15 (HR = 0.39; P = 0.0003) and MELD ≥ 15 (HR = 0.42; P = 0.0006). Among candidates with HCC, a benefit of LDLT was not seen for MELD <15 (HR = 0.82, P = 0.65) but was seen for MELD ≥ 15 (HR = 0.29, P = 0.043).

CONCLUSION

Across the range of MELD scores, patients without HCC derived a significant survival benefit when undergoing LDLT rather than waiting for DDLT in the MELD liver allocation era. Low MELD candidates with HCC may not benefit from LDLT.

SARS-CoV-2 infection and early mortality of waitlisted and solid organ transplant recipients in England: A national cohort study

Patients waitlisted for and recipients of solid organ transplants (SOT) are perceived to have a higher risk of contracting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and death; however, definitive epidemiological evidence is lacking. In a comprehensive national cohort study enabled by linkage of the UK transplant registry and Public Health England and NHS Digital Tracing services, we examined the incidence of laboratory-confirmed SARS-CoV-2 infection and subsequent mortality in patients on the active waiting list for a deceased donor SOT and recipients with a functioning SOT as of February 1, 2020 with follow-up to May 20, 2020. Univariate and multivariable techniques were used to compare differences between groups and to control for case-mix. One hundred ninety-seven (3.8%) of the 5184 waitlisted patients and 597 (1.3%) of the 46 789 SOT recipients tested positive for SARS-CoV-2. Mortality after testing positive for SARS-CoV-2 was 10.2% (20/197) for waitlisted patients and 25.8% (154/597) for SOT recipients. Increasing recipient age was the only variable independently associated with death after positive SARS-CoV-2 test. Of the 1004 transplants performed in 2020, 41 (4.1%) recipients have tested positive for SARS-CoV-2 with 8 (0.8%) deaths reported by May 20. These data provide evidence to support decisions on the risks and benefits of SOT during the coronavirus disease 2019 pandemic.

Changes in frailty are associated with waitlist mortality in patients with cirrhosis

BACKGROUND & AIMS

To date, studies evaluating the association between frailty and mortality in patients with cirrhosis have been limited to assessments of frailty at a single time point. We aimed to evaluate changes in frailty over time and their association with death/delisting in patients too sick for liver transplantation.

METHODS

Adults with cirrhosis, listed for liver transplantation at 8 US centers, underwent ambulatory longitudinal frailty testing using the liver frailty index (LFI). We used multilevel linear mixed-effects regression to model and predict changes in LFI (ΔLFI) per 3 months, based on age, gender, model for end-stage liver disease (MELD)-Na, ascites, and hepatic encephalopathy, categorizing patients by frailty trajectories. Competing risk regression evaluated the subhazard ratio (sHR) of baseline LFI and predicted ΔLFI on death/delisting, with transplantation as the competing risk.

RESULTS

We analyzed 2,851 visits from 1,093 outpatients with cirrhosis. Patients with severe worsening of frailty had worse baseline LFI and were more likely to have non-alcoholic fatty liver disease, diabetes, or dialysis-dependence. After a median follow-up of 11 months, 223 (20%) of the overall cohort died/were delisted because of sickness. The cumulative incidence of death/delisting increased by worsening ΔLFI group. In competing risk regression adjusted for baseline LFI, age, height, MELD-Na, and albumin, a 0.1 unit change in ΔLFI per 3 months was associated with a 2.04-fold increased risk of death/delisting (95% CI 1.35-3.09).

CONCLUSION

Worsening frailty was significantly associated with death/delisting independent of baseline frailty and MELD-Na. Notably, patients who experienced improvements in frailty had a lower risk of death/delisting. Our data support the longitudinal measurement of frailty, using the LFI, in patients with cirrhosis and lay the foundation for interventional work aimed at reversing frailty.

LAY SUMMARY

Frailty, as measured at a single time point, is predictive of death in patients with cirrhosis, but whether changes in frailty over time are associated with death is unknown. In a study of over 1,000 patients with cirrhosis who underwent frailty testing, we demonstrate that worsening frailty is strongly linked with mortality, regardless of baseline frailty and liver disease severity. Notably, patients who experienced improvements in frailty over time had a lower risk of death/delisting. Our data support the longitudinal measurement of frailty in patients with cirrhosis and lay the foundation for interventional work aimed at reversing frailty.

Height contributes to the gender difference in wait-list mortality under the MELD-based liver allocation system

This study examined factors associated with the gender disparity in wait-list mortality in the MELD era. Adult patients listed for liver transplantation from 2002 to 2008 were included. Females [12 585(36%)] and males [22 126(64%)] differed clinically by age (54 vs. 52 years), height (1.6 vs. 1.8 m), listing estimated glomerular filtration rate [(eGFR); 70 vs. 83 mL/min] and cirrhosis etiology. Holding MELD constant, females were at 19% (95% CI, 1.13-1.25, p < 0.001) higher risk of wait-list mortality than males under the current allocation system. The relative hazard increased with worsening renal function, whether measured by serum creatinine or eGFR. Adjustment for MELD, age, African-American race, cirrhosis etiology, region and ABO group attenuated this relative hazard (HR 1.16; 95% CI, 1.10-1.22; p < 0.001) but additional adjustment for height completely explained this gender disparity in wait-list mortality (HR 1.05; 95% CI, 0.98-1.12; p = 0.2). Transplantation rates, however, remained lower among females, even after adjustment for height (HR 0.88; 95% CI, 0.82-0.92; p < 0.001). In conclusion, under the current liver allocation system, women have a 19% increased risk of wait-list mortality compared to men with the same MELD scores. Height contributes to this gender disparity, possibly reflecting differences in transplantation rates for shorter individuals.

Racial/ethnic disparities in waitlisting for deceased donor kidney transplantation 1 year after implementation of the new national kidney allocation system

The impact of a new national kidney allocation system (KAS) on access to the national deceased-donor waiting list (waitlisting) and racial/ethnic disparities in waitlisting among US end-stage renal disease (ESRD) patients is unknown. We examined waitlisting pre- and post-KAS among incident (N = 1 253 100) and prevalent (N = 1 556 954) ESRD patients from the United States Renal Data System database (2005-2015) using multivariable time-dependent Cox and interrupted time-series models. The adjusted waitlisting rate among incident patients was 9% lower post-KAS (hazard ratio [HR]: 0.91; 95% confidence interval [CI], 0.90-0.93), although preemptive waitlisting increased from 30.2% to 35.1% (P < .0001). The waitlisting decrease is largely due to a decline in inactively waitlisted patients. Pre-KAS, blacks had a 19% lower waitlisting rate vs whites (HR: 0.81; 95% CI, 0.80-0.82); following KAS, disparity declined to 12% (HR: 0.88; 95% CI, 0.85-0.90). In adjusted time-series analyses of prevalent patients, waitlisting rates declined by 3.45/10 000 per month post-KAS (P < .001), resulting in ≈146 fewer waitlisting events/month. Shorter dialysis vintage was associated with greater decreases in waitlisting post-KAS (P < .001). Racial disparity reduction was due in part to a steeper decline in inactive waitlisting among minorities and a greater proportion of actively waitlisted minority patients. Waitlisting and racial disparity in waitlisting declined post-KAS; however, disparity remains.

Usefulness of extracorporeal membrane oxygenation as a bridge to lung transplantation: a descriptive study

BACKGROUND

This retrospective study investigated early outcome in patients with end-stage pulmonary disease bridged with extracorporeal membrane oxygenation (ECMO) with the intention of lung transplantation (LTx) in 2 Scandinavian transplant centers.

METHODS

ECMO was used as a bridge to LTx in 16 patients between 2005 and 2009 at Sahlgrenska and Helsinki University Hospitals. Most patients were late referrals for LTx, and all failed to stabilize on mechanical ventilation. Thirteen patients (7 men) who were a mean age of 41 ± 8 years (range, 25-51 years) underwent LTx after a mean ECMO support of 17 days (range, 1-59 days). Mean follow-up at 25 ± 19 months was 100% complete.

RESULTS

Three patients died on ECMO while waiting for a donor, and 1 patient died 82 days after LTx; thus, by intention-to-treat, the success for bridging is 81% and 1-year survival is 75%. All other patients survived, and 1-year survival for transplant recipients was 92% ± 7%. Mean intensive care unit stay after LTx was 28 ± 18 days (range, 3-53 days). All patients were doing well at follow-up; however, 2 patients underwent retransplantation due to bronchiolitis obliterans syndrome at 13 and 21 months after the initial ECMO bridge to LTx procedure. Lung function was evaluated at follow-up, and mean forced expiratory volume in 1 second was 2.0 ± 0.7 l (62% ± 23% of predicted) and forced vital capacity was 3.1 ± 0.6 l (74% ± 21% of predicted).

CONCLUSION

ECMO used as a bridge to LTx results in excellent short-term survival in selected patients with end-stage pulmonary disease.

Bridging and downstaging treatments for hepatocellular carcinoma in patients on the waiting list for liver transplantation

Several therapeutic procedures have been proposed as bridging treatments for patients with hepatocellular carcinoma (HCC) awaiting liver transplantation (LT). The most used treatments include transarterial chemoembolization and radiofrequency ablation. Surgical resection has also been successfully used as a bridging procedure, and LT should be considered a rescue treatment in patients with previous HCC resection who experience tumor recurrence or post-treatment severe decompensation of liver function. The aims of bridging treatments include decreasing the waiting list dropout rate before transplantation, reducing HCC recurrence after transplantation, and improving post-transplant overall survival. To date, no data from prospective randomized studies are available; however, for HCC patients listed for LT within the Milan criteria, prolonging the waiting time over 6-12 mo is a risk factor for tumor spread. Bridging treatments are useful in containing tumor progression and decreasing dropout. Furthermore, the response to pre-LT treatments may represent a surrogate marker of tumor biological aggressiveness and could therefore be evaluated to prioritize HCC candidates for LT. Lastly, although a definitive conclusion can not be reached, the experiences reported to date suggest a positive impact of these treatments on both tumor recurrence and post-transplant patient survival. Advanced HCC may be downstaged to achieve and maintain the current conventional criteria for inclusion in the waiting list for LT. Recent studies have demonstrated that successfully downstaged patients can achieve a 5-year survival rate comparable to that of patients meeting the conventional criteria without requiring downstaging.

Association Between Declined Offers of Deceased Donor Kidney Allograft and Outcomes in Kidney Transplant Candidates

IMPORTANCE

In the United States, substantial disparities in access to kidney transplant exist for wait-listed candidates with end-stage renal disease. The implications of transplant centers' willingness to accept kidney offers for access to transplant and mortality outcomes are unknown.

OBJECTIVE

To determine the outcomes for wait-listed kidney transplant candidates after the transplant center's refusal of a deceased donor kidney offer.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study obtained data from the United Network for Organ Sharing Potential Transplant Recipient data set on all deceased donor kidney offers in the United States made between January 1, 2008, and December 31, 2015. The final study cohort included adult patients who were wait-listed for kidney transplant and received at least 1 allograft offer during the study period (N = 280 041). Data analysis was conducted from June 1, 2018, to March 30, 2019.

EXPOSURE

Candidate state of residence.

MAIN OUTCOMES AND MEASURES

Waiting list outcome event groups included received deceased donor allograft, received living donor allograft, died while on the waiting list, removed from the waiting list without a transplant, or still on the waiting list at the end of follow-up.

RESULTS

Among the 280 041 kidney transplant candidates included in the study, the mean (SD) age at wait-listing was 51.1 (13.1) years, and male patients were predominant (171 517 [61.2%]). In this cohort, 81 750 candidates (29.2%) received a deceased donor kidney allograft, 30 870 (11.0%) received a living donor allograft, 25 967 (9.3%) died while on the waiting list, and 59 359 (21.2%) were removed from the waiting list. Overall, 10 candidates with at least 1 previous allograft offer died each day during the study period. Time to first offer was similar for candidates who received deceased donor kidney allograft compared with those who died while waiting (median [interquartile range {IQR}] time, 79 [16-426] days vs 78 [17-401] days, respectively). Deceased donor allograft recipients had a median of 17 offers (IQR, 6-44) over 422 days (IQR, 106-909 days), whereas candidates who died while waiting received a median of 16 offers (IQR, 6-41) over 651 days (IQR, 304-1117 days). Most kidneys (84%) were declined on behalf of at least 1 candidate before being accepted for transplant. As reported by centers, organ or donor quality concerns accounted for 8 416 474 (92.6%) of all declined offers, whereas offers were infrequently refused because of patient-related factors (232 193 [2.6%]), logistical limitations (49 492 [0.5%]), or other concerns. The odds of death after an offer and the median number of offers received prior to death varied considerably by state.

CONCLUSIONS AND RELEVANCE

This study found that transplant candidates appeared to receive a large number of viable deceased donor kidney offers that were refused on their behalf by transplant centers, potentially exacerbating the detrimental consequences of the organ shortage; increased transparency in organ allocation process and decisions may improve patient-centered care and access to kidney transplant.

Impact of the hepatopulmonary syndrome MELD exception policy on outcomes of patients after liver transplantation: an analysis of the UNOS database

BACKGROUND & AIMS

Patients with hepatopulmonary syndrome (HPS) are prioritized for liver transplantation (given exception points) due to their high pre- and post-transplantation mortality. However, few studies have evaluated the outcomes of these patients.

METHODS

We performed a retrospective cohort study using data submitted to the United Network for Organ Sharing in a study of the effects of room-air oxygenation on pre- and post-transplantation outcomes of patients with HPS. We identified thresholds associated with post-transplantation survival using cubic spline analysis and compared overall survival times of patients with and without HPS.

RESULTS

From 2002 through 2012, nine hundred and seventy-three patients on the liver transplant waitlist received HPS exception points. There was no association between oxygenation and waitlist mortality among patients with HPS exception points. Transplant recipients with more severe hypoxemia had increased risk of death after liver transplantation. Rates of 3-year unadjusted post-transplantation survival were 84% for patients with PaO2 of 44.1-54.0 mm Hg vs 68% for those with PaO2 ≤ 44.0 mm Hg. In multivariable Cox models, transplant recipients with an initial room-air PaO2 ≤ 44.0 mm Hg had significant increases in post-transplantation mortality (hazard ratio = 1.58; 95% confidence interval [CI]: 1.15-2.18) compared with those with a PaO2 of 44.1-54.0 mm Hg. Overall mortality was significantly lower among waitlist candidates with HPS exception points than those without (hazard ratio = 0.82; 95% CI: 0.70-0.96), possibly because patients with HPS have a reduced risk of pre-transplantation mortality and similar rate of post-transplantation survival.

CONCLUSIONS

Although there was no association between pre-transplantation oxygenation and waitlist survival in patients with HPS Model for End-Stage Liver Disease exception points, a pre-transplantation room-air PaO2 ≤ 44.0 mm Hg was associated with increased post-transplantation mortality. HPS Model for End-Stage Liver Disease exception patients had lower overall mortality compared with others awaiting liver transplantation, suggesting that the appropriateness of the HPS exception policy should be reassessed.

Liver transplantation for hepatocellular carcinoma: Where do we stand?

Hepatocellular carcinoma represents an important cause of morbidity and mortality worldwide. It is the sixth most common cancer and the fourth leading cause of cancer death. Liver transplantation is a key tool for the treatment of this disease in human therefore hepatocellular carcinoma is increasing as primary indication for grafting. Although liver transplantation represents an outstanding therapy for hepatocellular carcinoma, due to organ shortage, the careful selection and management of patients who may have a major survival benefit after grafting remains a fundamental question. In fact, only some stages of the disease seem amenable of this therapeutic option, stimulating the debate on the appropriate criteria to select candidates. In this review we focused on current criteria to select patients with hepatocellular carcinoma for liver transplantation as well as on the strategies (bridging) to avoid disease progression and exclusion from grafting during the stay on wait list. The treatments used to bring patients within acceptable criteria (down-staging), when their tumor burden exceeds the standard criteria for transplant, are also reported. Finally, we examined tumor reappearance following liver transplantation. This occurrence is estimated to be approximately 8%-20% in different studies. The possible approaches to prevent this outcome after transplant are reported with the corresponding results.

IMPact of the COVID-19 epidemic on the moRTAlity of kidney transplant recipients and candidates in a French Nationwide registry sTudy (IMPORTANT)

End stage kidney disease increase the risk of COVID-19 related death but how the kidney replacement strategy should be adapted during the pandemic is unknown. Chronic hemodialysis makes social distancing difficult to achieve. Alternatively, kidney transplantation could increase the severity of COVID-19 due to therapeutic immunosuppression and contribute to saturation of intensive care units. For these reasons, kidney transplantation was suspended in France during the first epidemic wave. Here, we retrospectively evaluated this strategy by comparing the overall and COVID-19 related mortality in kidney transplant recipients and candidates over the last three years. Cross-interrogation of two national registries for the period 1 March and 1 June 2020, identified 275 deaths among the 42812 kidney transplant recipients and 144 deaths among the 16210 candidates. This represents an excess of deaths for both populations, as compared with the same period the two previous years (mean of two previous years: 253 in recipients and 112 in candidates). This difference was integrally explained by COVID-19, which accounted for 44% (122) and 42% (60) of the deaths in recipients and candidates, respectively. Taking into account the size of the two populations and the geographical heterogeneity of virus circulation, we found that the excess of risk of death due to COVID-19 was similar for recipients and candidates in high viral risk area but four-fold higher for candidates in the low viral risk area. Thus, in case of a second epidemic wave, kidney transplantation should be suspended in high viral risk areas but maintained outside those areas, both to reduce the excess of deaths of candidates and avoid wasting precious resources.

Gender disparity in liver transplant waiting-list mortality: the importance of kidney function

Previous studies of men and women on the liver transplantation (LT) waiting list, without taking transplantation rates into account, have suggested a higher risk of mortality for women on the waiting list. The objective of this study was to compare men and women with respect to dying within 3 years of registration on the LT waiting list and to take into account both the immediate mortality risks and the transplantation rates. The analysis was based on Organ Procurement and Transplantation Network data for patients with end-stage liver disease (ESLD) on the waiting list who were registered between February 2002 and August 2009. Competing risk survival analysis was performed to assess the gender disparity in waiting-list mortality; 42,322 patients and 610,762 person-months of waiting-list experience were included in the analysis. The risk of dying within 3 years of listing was 19% and 17% in women and men, respectively (P < 0.0001). Among patients with kidney disease and especially those not on dialysis with an estimated glomerular filtration rate (eGFR) ≥15 and <30 mL/minute/1.73 m(2), women had a substantially higher risk of dying on the waiting list within 3 years of registration versus men (26% versus 20%, P = 0.001). This disparity was related to lower transplantation rates in women (transplantation rate ratio = 0.68, P < 0.0001). Controlling for eGFR and other variables related to mortality risk, we found that the overall female-male disparity disappeared. In conclusion, among patients with ESLD and kidney dysfunction who are not on dialysis, there is a substantial gender disparity in LT waiting-list mortality. Our analysis suggests as an explanation the fact that women have lower transplantation rates than men in this group. The lower transplantation rates can be explained in part by the fact that Model for End-Stage Liver Disease scores tend to be lower for women versus men because they are based on serum creatinine rather than the glomerular filtration rate.

Sex-based disparities in delisting for being "too sick" for liver transplantation

Women with cirrhosis awaiting liver transplantation (LT) experience higher rates of waitlist mortality than men; it is unknown whether practices surrounding delisting for being "too sick" for LT contribute to this disparity beyond death alone. We conducted an analysis of patients listed for LT in the United Network for Organ Sharing/Organ Procurement and Transplantation Network not receiving exception points from May 1, 2007 to July 1, 2014 with a primary outcome of delisting with removal codes of "too sick" or "medically unsuitable." A total of 44 388 patients were included; 4458 were delisted for being "too sick" for LT. Delisting was more frequent in women (11% vs 9%, P < .001). Compared to delisted men, delisted women differed in age (58 vs 57), non-hepatitis C virus listing diagnoses (69% vs 56%), hepatic encephalopathy (36% vs 31%), height (161.9 vs 177.0 cm), private insurance (47% vs 52%), and Karnofsky performance status (60 vs 70) (P < .001 for all). There were no differences in Model for End-Stage Liver Disease including serum sodium and Child Pugh Scores. A competing risk analysis demonstrated that female sex was independently associated with a 10% (confidence interval 2%-18%) higher risk of delisting when accounting for rates of death and transplantation and adjusting for confounders. This study demonstrates a significant disparity in delisting practices by sex, highlighting the need for better assessments of sickness, particularly in women.

Regional differences in recipient waitlist time and pre- and post-transplant mortality after the 2006 United Network for Organ Sharing policy changes in the donor heart allocation algorithm

OBJECTIVES

This study examined the impact of the United Network for Organ Sharing (UNOS) policy changes for regional differences in waitlist time and mortality before and after heart transplantation.

BACKGROUND

The 2006 UNOS thoracic organ allocation policy change was implemented to allow for greater regional sharing of organs for heart transplantation.

METHODS

We analyzed 36,789 patients who were listed for heart transplantation from January 1999 through April 2012. These patients were separated into 2 eras centered on the July 12, 2006 UNOS policy change. Pre- and post-transplantation characteristics were compared by UNOS regions.

RESULTS

Waitlist mortality decreased nationally (up to 180 days: 13.3% vs. 7.9% after the UNOS policy change, p < 0.001) and within each region. Similarly, 2-year post-transplant mortality decreased nationally (2-year mortality: 17.3% vs. 14.6%; p < 0.001) as well as regionally. Waitlist time for UNOS status 1A and 1B candidates increased nationally 17.8 days on average (p < 0.001) with variability between the regions. The greatest increases were in Region 9 (59.2-day increase, p < 0.001) and Region 4 (41.2-day increase, p < 0.001). Although the use of mechanical circulatory support increased nearly 2.3-fold nationally in Era 2, significant differences were present on a regional basis. In Regions 6, 7, and 10, nearly 40% of those transplanted required left ventricular assist device bridging, whereas only 19.6%, 22.3%, and 15.5% required a left ventricular assist device in regions 3, 4, and 5, respectively.

CONCLUSIONS

The 2006 UNOS policy change has resulted in significant regional heterogeneity with respect to waitlist time and reliance on mechanical circulatory support as a bridge to transplantation, although overall both waitlist mortality and post-transplant survival are improved.

Expanding the donor pool for liver transplantation with marginal donors

The current supply of acceptable donor livers is not sufficient to meet the demands of listed patients awaiting transplantation resulting in thousands of deaths each year. Increased utilization of marginal livers may help alleviate this supply/demand mismatch by expanding the donor liver pool. The current status of liver transplantation using marginal donor grafts and efforts to optimize usage are discussed with attention to elderly donors, steatotic livers, donors after circulatory death, and split liver grafts.

Split liver transplantation: Current developments

In 1988, Rudolf Pichlmayr pioneered split liver transplantation (SLT), enabling the transplantation of one donor liver into two recipients - one pediatric and one adult patient. In the same year, Henri Bismuth and colleagues performed the first full right/full left split procedure with two adult recipients. Both splitting techniques were rapidly adopted within the transplant community. However, a SLT is technically demanding, may cause increased perioperative complications, and may potentially transform an excellent deceased donor organ into two marginal quality grafts. Thus, crucial evaluation of donor organs suitable for splitting and careful screening of potential SLT recipients is warranted. Furthermore, the logistic background of the splitting procedure as well as the organ allocation policy must be adapted to further increase the number and the safety of SLT. Under defined circumstances, in selected patients and at experienced transplant centers, SLT outcomes can be similar to those obtained in full organ LT. Thus, SLT is an important tool to reduce the donor organ shortage and waitlist mortality, especially for pediatric patients and small adults. The present review gives an overview of technical aspects, current developments, and clinical outcomes of SLT.

Moderate ascites identifies patients with low model for end-stage liver disease scores awaiting liver transplantation who have a high mortality risk

Donor livers are offered to patients with the highest risk of death. How ascites could inform risk models to reduce liver transplant wait-list mortality is unclear. All adult candidates for primary liver transplantation for cirrhosis without exception points who were registered with the Organ Procurement and Transplantation Network from 2005 to 2007 composed our study cohort. Using Cox models and advanced discriminative metrics and paying attention to geographic disparities, we evaluated the additional risk discrimination of moderate ascites over that of the Model for End-Stage Liver Disease (MELD) or the Model for End-Stage Liver Disease plus serum sodium (MELD-Na) alone for the prediction of 90-day wait-list mortality. Additional analyses examined lower mortality risk candidates and those listed in high-demand, low-supply United Network for Organ Sharing regions in which accounting for ascites may most significantly affect wait-list mortality. Between 2005 and 2007, 18,124 subjects were listed for liver transplantation. Mortality was higher in patients with moderate ascites (15.4% versus 6.0%, P < 0.0001), and this risk persisted despite adjustments for MELD (hazard ratio = 1.58, 95% confidence interval = 1.42-1.76) and MELD-Na (hazard ratio = 1.42, 95% confidence interval = 1.28-1.58). The effect of moderate ascites was more prominent with a MELD score <21 (equal to 4.7 MELD units) or with a MELD-Na score <21 (equal to 3.5 MELD-Na units). Wait-list mortality was higher in patients with moderate ascites who were listed in high-demand, limited-supply regions (25.8% versus 17.5% at 1 year, P < 0.01). With the addition of moderate ascites, there was improvement in the overall risk model, particularly with a MELD score <21, as measured by the C index and integrated discrimination improvement. Moderate ascites informed risk prediction, particularly with a MELD score <21 and in high-demand, limited-supply regions. Under the MELD system, the presence of moderate ascites should prompt clinicians to consider strategies to expand access to transplantation, such as the use of extended donor liver grafts.

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 6 months 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.

Limited health literacy and adverse outcomes among kidney transplant candidates

More than one-third of US adults have limited health literacy, putting them at risk of adverse clinical outcomes. We evaluated the prevalence of limited health literacy among 1578 adult kidney transplant (KT) candidates (May 2014-November 2017) and examined its association with listing for transplant and waitlist mortality in this pilot study. Limited health literacy was assessed at KT evaluation by using a standard cutoff score ≤5 on the Brief Health Literacy Screen (score range 0-12, lower scores indicate worse health literacy). We used logistic regression and adjusted Cox proportional hazards models to identify risk factors for limited health literacy and to quantify its association with listing and waitlist mortality. We found that 8.9% of candidates had limited health literacy; risk factors included less than college education (adjusted odds ratio [aOR] = 2.87, 95% confidence interval [CI]:1.86-4.43), frailty (aOR = 1.85, 95% CI:1.22-2.80), comorbidity (Charlson comorbidity index [1-point increase] aOR = 1.12, 95% CI: 1.04-1.20), and cognitive impairment (aOR = 3.45, 95% CI: 2.20-5.41) after adjusting for age, sex, race, and income. Candidates with limited health literacy had a 30% (adjusted hazard ratio = 0.70, 95% CI: 0.54-0.91) decreased likelihood of listing and a 2.42-fold (95% CI: 1.16- to 5.05-fold) increased risk of waitlist mortality. Limited health literacy may be a salient mechanism in access to KT; programs to aid candidates with limited health literacy may improve outcomes and reduce disparities.

Access to Kidney Transplantation among HIV-Infected Waitlist Candidates

BACKGROUND AND OBJECTIVES

Kidney transplantation among HIV-infected patients with ESRD confers a significant survival benefit over remaining on dialysis. Given the high mortality burden associated with dialysis, understanding access to kidney transplantation after waitlisting among HIV+ candidates is warranted.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data from the Scientific Registry of Transplant Recipients were linked to Intercontinental Marketing Statistics pharmacy fills (January 1, 2001 to October 1, 2012) so that we could identify and study 1636 HIV+ (defined as having filled one or more antiretroviral medications unique to HIV treatment) and 72,297 HIV- kidney transplantation candidates.

RESULTS

HIV+ waiting list candidates were more often young (<50 years old: 62.7% versus 37.6%; P<0.001), were more often men (75.2% versus 59.3%; P<0.001), were more often black (73.6% versus 27.9%; P<0.001), had longer time on dialysis (years: 2.5 versus 0.8; P<0.001), were more often coinfected with hepatitis C virus (9.0% versus 3.9%; P<0.001), and were less likely to remain active on the waiting list (37.7% versus 49.4%; P<0.001). Waitlist mortality among HIV+ candidates was similar compared with HIV- candidates (adjusted hazard ratio, 1.03; 95% confidence interval, 0.89 to 1.20; P=0.67). In contrast, likelihood of living donor kidney transplantation was 47% lower (adjusted hazard ratio, 0.53; 95% confidence interval, 0.44 to 0.64; P<0.001), and there was a trend toward lower likelihood of deceased donor kidney transplantation (adjusted hazard ratio, 0.87; 95% confidence interval, 0.74 to 1.01; P=0.07) compared with in HIV- candidates.

CONCLUSIONS

Our findings highlight the need for additional study to better understand disparities in access to kidney transplantation, particularly living donor kidney transplantation, among HIV+ kidney waitlist candidates.