Significant improvements, but consistent disparities in survival for African Americans after liver transplantation

Racial disparities in posttransplant outcomes among recipients undergoing simultaneous liver-kidney transplantation

BACKGROUND

Patients with end-stage cirrhosis may experience renal dysfunction, necessitating a simultaneous kidney-liver transplant (SKLT). Guidelines have been put forth by the United Network for Organ Sharing (UNOS) to streamline the SKLT allocation process and ensure equitable access to transplantation. However, there is a scarcity of literature on racial and ethnic disparities in post-SKLT outcomes.

METHODS

The UNOS Standard Transplant Analysis and Research Database was queried from 2005 to 2019 to study SKLT patients. Patients were stratified by race: White (reference group) recipients (n = 3513), Black recipients (n = 859), Hispanic recipients (n = 964), Asian recipients (n = 206), and other recipients (n = 85). Primary endpoints included all-cause mortality and graft failure while secondary endpoints were specific causes of death.

RESULTS

Hispanic recipients had a lower risk of all-cause mortality (aHR: 0.79, 95% CI: 0.68-0.93, P = 0.003), while Black recipients had a significantly increased risk of graft failure compared to Whites (aHR: 1.63, 95% CI: 1.16-2.30, P = 0.005). Evaluation of specific causes of recipient death revealed a higher risk of death due to gastrointestinal hemorrhage among Blacks (aHR: 4.16, 95% CI: 1.04-16.68, P = 0.04).

CONCLUSION

Our study findings show Black patients experience higher rates of graft failure compared to White counterparts. The reasons for these disparities are not fully understood but likely a combination of biological and social factors. Further investigation is warranted to ascertain the specific factors influencing these outcomes.

Acute Liver Failure Etiology Determines Long-Term Outcomes in Patients Undergoing Liver Transplantation: An Analysis of the UNOS Database

Background: Acute liver failure (ALF) involves rapid liver injury, often leading to multi-organ failure. Liver transplantation (LT) has improved survival rates, with U.S. rates reaching 92%. This study analyzes UNOS data (2002-2020) to evaluate long-term survival and identify risk factors affecting waitlist and post-LT outcomes in ALF patients. Methods: A retrospective analysis was performed on adult ALF patients waitlisted for LT (Status 1/1A). ALF etiologies, including viral infections, drug-induced liver injury (DILI), acetaminophen (APAP) overdose, autoimmune hepatitis (AIH), Wilson disease (WD), and unknown causes, were assessed with patient and donor characteristics. Kaplan-Meier and Cox regression analyses identified predictors of patient and graft survival. Sensitivity analysis confirmed the model's robustness. Results: We identified 2759 ALF patients. APAP (HR 1.7; p < 0.001) and unknown etiology (HR 1.3; p = 0.037) were linked to higher waitlist removal risk, while WD (HR 0.36; p < 0.001) increased LT probability. Among 2014 LT recipients, WD showed improved survival (HR 0.53; p = 0.002). Black/African American race (HR 1.47; p < 0.001), diabetes (HR 1.81; p < 0.001), and encephalopathy (HR 1.27; p < 0.001) predicted higher mortality. AIH had the lowest 1- and 10-year survival (83% and 62%), while APAP had the lowest 5-year survival (76%). WD had the highest graft survival at 1, 5, and 10 years (93%, 88%, and 80%). Conclusions: ALF etiology significantly affects survival outcomes. AIH and APAP are associated with worse survival, while WD shows favorable outcomes. Tailored post-LT management is essential to improve survival in ALF patients.

Area-Level Social Deprivation and Cytomegalovirus Seropositivity at the Time of Solid Organ Transplant

Importance

Cytomegalovirus (CMV) is associated with significant morbidity and mortality in solid organ transplant (SOT) recipients. The risk factors for CMV seropositivity in SOT recipients, including area-level social deprivation in the US, have not been fully characterized.

Objective

To (1) evaluate CMV seroprevalence, (2) assess the recipient characteristics associated with CMV seropositivity, and (3) assess the association of area-level social deprivation index (SDI) scores with pretransplant CMV serostatus.

Design, Setting, and Participants

This retrospective cross-sectional analysis of the Scientific Registry of Transplant Recipients database included all adult (aged ≥18 years) SOT recipients from January 1, 2008, to May 31, 2022. Data were analyzed from April 10 to October 25, 2023.

Exposure

Recipient characteristics and area-level SDI.

Main Outcomes and Measures

Multivariable generalized linear models were used to evaluate the association between (1) patient characteristics and CMV and (2) social deprivation (measured by SDI scores, which were assessed in quintiles, from lowest to highest) and CMV seropositivity. In addition, differences based on patient demographics and the transplanted organ(s) were evaluated.

Results

Among the 389 288 SOT recipients included in the analysis, mean (SD) age was 53.3 (13.0) years; 63.0% were male, 21.4% were Black, 15.2% were Hispanic White, 56.2% were non-Hispanic White, and 62.7% were CMV seropositive. The mean (SD) age was higher among CMV seropositive (54.0 [12.7] years) compared with CMV seronegative (52.0 [13.5] years) patients. Seropositivity for CMV was higher among women (69.9%) than men (58.5%) and among Black (74.8%) and Hispanic White (80.2%) patients compared with non-Hispanic White patients (50.4%). Seropositivity for CMV was highest among kidney (64.5%), liver (63.6%), and kidney and liver (66.2%) recipients. Greater SDI scores were associated with greater CMV seropositivity, ranging from 51.7% for the least deprived to 75.5% for the most deprived quintiles (P < .001), independent of age, sex, or race.

Conclusions and Relevance

In this cross-sectional study, an association between SDI and CMV seropositivity was observed among SOT recipients, independent of age, sex, or race and ethnicity. To optimize posttransplant outcomes in CMV seropositive recipients, efforts targeting prevention of CMV reactivation need to be prioritized in these higher-risk populations.

Disparities in Liver Transplant Outcomes: Race/Ethnicity and Individual- and Neighborhood-Level Socioeconomic Status

Race/ethnicity and individual-level socioeconomic status (SES) may contribute to health disparities in liver transplant (LT) outcomes. The socioeconomic conditions of a neighborhood may either mitigate or exacerbate these health disparities. This retrospective study investigated the relationship between race/ethnicity, individual- and neighborhood-level SES, and LT outcomes, and whether neighborhood-level SES modified the relationship between individual factors and LT outcomes. Adult individuals who underwent LT between 2010 and 2019 (n = 55,688) were identified from the United Network for Organ Sharing database. Primary exposures were race/ethnicity, education, primary insurance type, and the Social Deprivation Index (SDI) scores. Education and primary insurance type were used as proxies for individual-level SES, while SDI scores were used as a proxy for neighborhood-level SES. The primary outcome was time to occurrence of graft failure or mortality. Cox proportional hazard models were used to examine the associations between the exposures and outcomes. LT recipients who were Black (hazard ratio [HR]: 1.27, p < .0001), completed high school or less (HR: 1.06, p = .002), and had public insurance (HR: 1.14, p < .0001) had a higher rate of graft failure or mortality than those who were White, completed more than high school, and had private insurance, respectively. The SDI scores were not significantly associated with LT outcomes when adjusting for individual factors (HR: 1.02, p = .45) and did not modify the associations between individual factors and LT outcomes. Findings of this study suggest that disparities based on individual factors were not modified by neighborhood-level SES. Tailored interventions targeting the unique needs associated with race/ethnicity and individual-level SES are needed to optimize LT outcomes.

Equity in liver transplantation: are we any closer?

PURPOSE OF REVIEW

As policies governing liver transplantation (LT) continue to change and influence clinical practice, it is important to monitor trends in equitable access and outcomes amongst patients. The purpose of this review is to closely examine recent advances and findings in health equity research in LT over the last 2 years; specifically evaluating inequities at the different stages of LT (referral, evaluation, listing, waitlist outcomes and post-LT outcomes).

RECENT FINDINGS

Advancements in geospatial analysis have enabled investigators to identify and begin to study the role of community level factors (such as neighborhood poverty, increased community capital/urbanicity score) in driving LT disparities. There has also been a shift in investigating center specific characteristics that contributes to disparities in waitlist access. Modification to the current model for end stage liver disease (MELD) score policy accounting for height differences is also crucial to eradicating the disparity in LT amongst sexes. Lastly, Black pediatric patients have been shown to have higher rates of death and worse posttransplant outcome after transitioning to adult healthcare.

SUMMARY

Although, there have been some advances in methodology and policies, inequities in waitlist access, waitlist outcomes and posttransplant outcomes continue to be pervasive in the field of LT. Future directions include expansion of social determinants of health measures, inclusion of multicenter designs, MELD score modification and investigation into drivers of worse posttransplant outcomes in Black patients.