The Impact of Primary Liver Disease and Social Determinants in a Mixed Donor Liver Transplant Program: A Single-Center Analysis

Neighborhood-level social determinants of health measures independently predict receipt of living donor liver transplantation in the United States

Disparities exist in the access to living donor liver transplantation (LDLT) in the United States. However, the association of neighborhood-level social determinants of health (SDoH) on the receipt of LDLT is not well-established. This was a retrospective cohort study of adult liver transplant recipients between January 1, 2005 and December 31, 2021 at centers performing LDLT using the United Network for Organ Sharing database, which was linked through patients' ZIP code to a set of 24 neighborhood-level SDoH measures from different data sources. Temporal trends and center differences in neighborhood Social Deprivation Index (SDI), a validated scale of socioeconomic deprivation ranging from 0 to 100 (0=least disadvantaged), were assessed by transplant type. Multivariable logistic regression evaluated the association of increasing SDI on receipt of LDLT [vs. deceased donor liver transplantation (DDLT)]. There were 51,721 DDLT and 4026 LDLT recipients at 59 LDLT-performing centers during the study period. Of the 24 neighborhood-level SDoH measures studied, the SDI was most different between the 2 transplant types, with LDLT recipients having lower SDI (ie, less socioeconomic disadvantage) than DDLT recipients (median SDI 37 vs. 47; p < 0.001). The median difference in SDI between the LDLT and DDLT groups significantly decreased from 13 in 2005 to 3 in 2021 ( p = 0.003). In the final model, the SDI quintile was independently associated with transplant type ( p < 0.001) with a threshold SDI of ~40, above which increasing SDI was significantly associated with reduced odds of LDLT (vs. reference SDI 1-20). As a neighborhood-level SDoH measure, SDI is useful for evaluating disparities in the context of LDLT. Center outreach efforts that aim to reduce disparities in LDLT could preferentially target US ZIP codes with SDI > 40.

Living donor liver transplantation can address disparities in transplant access for patients with primary sclerosing cholangitis

BACKGROUND

Liver transplantation (LT) is frequently lifesaving for people living with primary sclerosing cholangitis (PSC). However, patients are waitlisted for LT according to the model for end-stage liver disease-sodium (MELD-Na) score, which may not accurately reflect the burden of living with PSC. We sought to describe and analyze the clinical trajectory for patients with PSC referred for LT, in a mixed deceased donor/living donor transplant program.

METHODS

This was a retrospective cohort study from November 2012 to December 2019, including all patients with PSC referred for assessment at the University Health Network Liver Transplant Clinic. Patients who required multiorgan transplant or retransplantation were excluded. Liver symptoms, hepatobiliary malignancy, MELD-Na progression, and death were abstracted from chart review. Competing risk analysis was used for timing of LT, transplant type, and death.

RESULTS

Of 172 PSC patients assessed, 84% (n = 144) were listed of whom 74% were transplanted. Mean age was 47.6 years, and 66% were male. Overall mortality was 18.2% at 2 years. During the follow-up, 16% (n = 23) were removed from the waitlist for infection, clinical deterioration, liver-related mortality or new cancer; 3 had clinical improvement. At listing, 82% (n = 118) had a potential living donor (pLD). Patients with pLD had significantly lower waitlist and liver-related waitlist mortality (HR 0.20, p<0.001 and HR 0.17, p<0.001, respectively), and higher rates of transplantation (HR 1.83, p = 0.05). Exception points were granted to 13/172 (7.5%) patients.

CONCLUSIONS

In a high-volume North American LT center, most patients with PSC assessed for transplant were listed and subsequently transplanted. However, this was a consequence of patients engaging in living donor transplantation. Our findings support the concern from patients with PSC that MELD-Na allocation does not adequately address their needs.

A Population-Based Analysis of the Impact of the COVID-19 Pandemic on Solid Organ Transplantation in Ontario, Canada: Policy Response and Changes in Volume and 90-Day Outcomes

Objectives

To evaluate the impact of the COVID-19 pandemic on solid organ transplantation.

Background

COVID-19 caused unprecedented disruption to solid organ transplantation (kidney, liver, heart, lung). Concerns about safety and decreases in deceased donors due to pandemic lockdowns have been described as potential causes.

Methods

We report population-based rates of transplantation during the first 3 waves of COVID-19 in Ontario, Canada (March 1, 2020-July 3, 2021) versus a pre-COVID-19 baseline period (January 1, 2017-February 29, 2020). Poisson models were used to predict transplantation rates during COVID-19, based on pre-COVID-19 rates, and generate observed to expected rate ratios (RRs). Ninety-day transplant outcomes (mortality, retransplantation, transplant nephrectomy) were captured.

Results

A 34.4% decrease (RR, 0.656; 95% confidence interval [CI], 0.586-0.734) in transplant rates was observed, coinciding with wave 1 and the deployment of a provincial transplant triaging system. Transplants decreased by 14.6% in wave 2 (RR, 0.854; 95% CI, 0.770-0.947) and 23.1% in wave 3 (RR, 0.769; 95% CI, 0.690-0.857) despite the triaging system not being activated. Overall, there was a 24.3% decrease (RR, 0.757; 95% CI, 0.679-0.844) in transplant rates, equivalent to 409 fewer transplants. No sustained changes were observed in heart or liver but sustained and large decreases were seen for lung (RR, 0.664; 95% CI, 0.482-0.915) and kidney (RR, 0.721; 95% CI, 0.602-0.863) transplantation. A low prevalence (1.7%) of COVID-19 infection within 90 days of transplantation was seen. No differences were observed in other 90-day outcomes.

Conclusions

Early safety concerns limited transplantation to immediate life-saving procedures; however, the reductions in kidney and lung transplants continued for the rest of the pandemic, where no restrictions were in place.

Survival After Liver Transplantation: An International Comparison Between the United States and the United Kingdom in the Years 2008-2016

BACKGROUND

Compared with the United States, risk-adjusted mortality in the United Kingdom has historically been worse in the first 90 d following liver transplantation (LT) and better thereafter. In the last decade, there has been considerable change in the practice of LT internationally, but no contemporary large-scale international comparison of posttransplant outcomes has been conducted. This study aimed to determine disease-specific short- and long-term mortality of LT recipients in the United States and the United Kingdom.

METHODS

This retrospective international multicenter cohort study analyzed adult (≥18 y) first-time LT recipients between January 2, 2008, and December 31, 2016, using the Organ Procurement and Transplantation Network/United Network for Organ Sharing and the UK Transplant Registry databases. Time-dependent Cox regression estimated hazard ratios (HRs) comparing disease-specific risk-adjusted mortality in the first 90 d post-LT, between 90 d and 1 y, and between 1 and 5 y.

RESULTS

Forty-two thousand eight hundred seventy-four US and 4950 UK LT recipients were included. The main LT indications in the United States and the United Kingdom were hepatocellular carcinoma (25.4% and 24.9%, respectively) and alcohol-related liver disease (20.3% and 27.1%, respectively). There were no differences in mortality during the first 90 d post-LT (reference: United States; HR, 0.96; 95% confidence interval [CI], 0.82-1.12). However, between 90 d and 1 y (HR, 0.71; 95% CI, 0.59-0.85) and 1 and 5 y (HR, 0.71; 95% CI, 0.63-0.81]) the United Kingdom had lower mortality. The mortality differences between 1 and 5 y were most marked in hepatocellular carcinoma (HR, 0.71; 95% CI, 0.58-0.88) and alcohol-related liver disease patients (HR, 0.64; 95% CI, 0.45-0.89).

CONCLUSIONS

Risk-adjusted mortality in the United States and the United Kingdom was similar in the first 90 d post-LT but better in the United Kingdom thereafter. International comparisons of LT may highlight differences in healthcare delivery and help benchmarking by identifying modifiable factors that can facilitate improved global outcomes in LT.

Are MELD and MELDNa Still Reliable Tools to Predict Mortality on the Liver Transplant Waiting List?

Liver transplantation is the only curative treatment for end-stage liver disease. Unfortunately, the scarcity of donor organs and the increasing pool of potential recipients limit access to this life-saving procedure. Allocation should account for medical and ethical factors, ensuring equal access to transplantation regardless of recipient's gender, race, religion, or income. Based on their short-term prognosis prediction, model for end-stage liver disease (MELD) and MELD sodium (MELDNa) have been widely used to prioritize patients on the waiting list for liver transplantation resulting in a significant decrease in waiting list mortality/removal. Recent concern has been raised regarding the prognostic accuracy of MELD and MELDNa due, in part, to changes in recipients' profile such as body mass index, comorbidities, and general condition, including nutritional status and cause of liver disease, among others. This review aims to provide a comprehensive view of the current state of MELD and MELDNa advantages and limitations and promising alternatives. Finally, it will explore future options to increase the donor pool and improve donor-recipient matching.

Long-term Outcomes of Pediatric Living Versus Deceased Donor Liver Transplantation Recipients: A Systematic Review and Meta-analysis

Living donor liver transplantation (LDLT) emerged in the 1980s as a viable alternative to scarce cadaveric organs for pediatric patients. However, pediatric waitlist mortality remains high. Long-term outcomes of living and deceased donor liver transplantation (DDLT) are inconsistently described in the literature. Our aim was to systematically review the safety and efficacy of LDLT after 1 year of transplantation among pediatric patients with all causes of liver failure. We searched the MEDLINE, Medline-in-Process, MEDLINE Epub Ahead of Print, Embase + Embase Classic (OvidSP), and Cochrane (Wiley) from February 1, 1947 to February 26, 2020, without language restrictions. The primary outcomes were patient and graft survival beyond 1 year following transplantation. A meta-analysis of unadjusted and adjusted odds and hazard ratios was performed using a random-effects model. A total of 24 studies with 3677 patients who underwent LDLT and 9098 patients who underwent DDLT were included for analysis. In patients with chronic or combined chronic liver failure and acute liver failure (ALF), 1-year (odds ratio [OR], 0.68; 95% confidence interval [CI], 0.53-0.88), 3-year (OR, 0.73; 95% CI, 0.61-0.89), 5-year (OR, 0.71; 95% CI, 0.57-0.89), and 10-year (OR, 0.42; 95% CI, 0.18-1.00) patient and 1-year (OR, 0.50; 95% CI, 0.35-0.70), 3-year (OR, 0.55; 95% CI, 0.37-0.83), 5-year (OR, 0.5; 95% CI, 0.32-0.76), and 10-year (OR, 0.26; 95% CI, 0.14-0.49) graft survival were consistently better in LDLT recipients compared with those in DDLT recipients. In patients with ALF, no difference was seen between the 2 groups except for 5-year patient survival (OR, 0.60; 95% CI, 0.38-0.95), which favored LDLT. Sensitivity analysis by era showed improved survival in the most recent cohort of patients, consistent with the well-described learning curve for the LDLT technique. LDLT provides superior patient and graft survival outcomes relative to DDLT in pediatric patients with chronic liver failure and ALF. More resources may be needed to develop infrastructures and health care systems to support living liver donation.