Race is not a critical factor in orthotopic liver transplantation

Ethnic and Age Disparities in Outcomes Among Liver Transplant Waitlist Candidates

BACKGROUND

Despite the increasing prevalence of end-stage liver disease in older adults, there is no consensus to determine suitability for liver transplantation (LT) in the elderly. Disparities in LT access exist, with a disproportionately lower percentage of African Americans (AAs) receiving LT. Understanding waitlist outcomes in older adults, specifically AAs, will identify opportunities to improve LT access for this vulnerable population.

METHODS

All adult, liver-only white and AA LT waitlist candidates (January 1, 2003 to October 1, 2015) were identified in the Scientific Registry of Transplant Recipients. Age and race categories were defined: younger white (age <60 years), younger AA, older white (age, ≥60 years), and older AA. Outcomes were delisting, transplantation, and mortality and were modeled using Fine and Gray competing risks.

RESULTS

Among 101 805 candidates, 58.4% underwent transplantation, 14.7% died while listed, and 21.4% were delisted. Among those delisted, 36.1% died, whereas 7.4% were subsequently relisted. Both older AAs and older whites were more likely than younger whites to be delisted and to die after delisting. Older whites had higher incidence of waitlist mortality than younger whites (subdistribution hazard ratio, 1.07; 95% confidence interval, 1.01-1.13). All AAs and older whites had decreased incidence of LT, compared with younger whites.

CONCLUSIONS

Both older age and AA race were associated with decreased cumulative incidence of transplantation. Independent of race, older candidates had increased incidences of delisting and mortality after delisting than younger whites. Our findings support the need for interventions to ensure medical suitability for LT among older adults and to address disparities in LT access for AAs.

Variation in access to the liver transplant waiting list in the United States

BACKGROUND

We sought to compare liver transplant waiting list access by demographics and geography relative to the pool of potential liver transplant candidates across the United States using a novel metric of access to care, termed a liver wait-listing ratio (LWR).

METHODS

We calculated LWRs from national liver transplant registration data and liver mortality data from the Scientific Registry of Transplant Recipients and the National Center for Healthcare Statistics from 1999 to 2006 to identify variation by diagnosis, demographics, geography, and era.

RESULTS

Among patients with ALF and CLF, African Americans had significantly lower access to the waiting list compared with whites (acute: 0.201 versus 0.280; pre-MELD 0.201 versus 0.290; MELD era: 0.201 versus 0.274; all, P<0.0001) (chronic: 0.084 versus 0.163; pre-MELD 0.085 versus 0.179; MELD 0.084 versus 0.154; all, P<0.0001). Hispanics and whites had similar LWR in both eras (both P>0.05). In the MELD era, female subjects had greater access to the waiting list compared with male subjects (acute: 0.428 versus 0.154; chronic: 0.158 versus 0.140; all, P<0.0001). LWRs varied by three-fold by state (pre-MELD acute: 0.122-0.418, chronic: 0.092-0.247; MELD acute: 0.121-0.428, chronic: 0.092-0.243).

CONCLUSIONS

The marked inequity in early access to liver transplantation underscores the need for local and national policy initiatives to affect this disparity.

Outcomes in adult and pediatric liver transplantation among various ethnic groups

BACKGROUND

The reported patient and graft survivals among adults post-orthotopic liver transplantation (OLT) are variable, with an apparent discrepancy between ethnic groups. The aim of this study was to evaluate the impact of ethnicity on patient and graft survivals among adult and pediatric patients.

METHODS

A retrospective analysis from the UNOS/OPTN databank between January 1995 and December 2006 was performed on adult and pediatric liver transplant recipients. Patients were divided into 4 groups based on ethnicity: African Americans, Hispanic, Caucasians, and other. Kaplan-Meier (KM) analysis was used to calculate patient and graft survival. Log-rank tests were used to compare survival rates between groups.

RESULTS

In our study 42,710 OLT patients were included in the analysis, 90% of whom were adults. Of the 38,639 adult recipients, 29,432 (76.1%) were Caucasian, 4369 (11.3%) were Hispanic, 2963 (7.7%) were African American, and the remaining 1875 (4.9%) were of other ethnicities. KM estimates and Cox regression analyses demonstrated that there was a significant ethnic difference in both patient and graft survivals at 1, 3, 5, and 10 years. African Americans showed a lower rate (P<.001). Of the 4341 pediatric recipients, 2461 (56.7%) were Caucasian, 797 (18.4%) were Hispanic, 824 (18.9%) were African American, and the remaining 259 (5.9%) were of other ethnicities. Unlike the adults, there were no significant differences among ethnic groups in terms of patient (P=.31) and graft (P=.33) survival at 1, 3, 5, and 10 years after OLT.

CONCLUSION

These results showed that adult African American OLT patients have a reduced transplantation rate and a worse survival rate when compared with other ethnicities in the adult but not in the pediatric population. This information suggests that further studies are indicated to identify the causes of racial differences in transplant access and outcomes in the adult patient population.

Role of gender and race mismatch and graft failure in patients undergoing liver transplantation

Previous data have suggested an increased risk of graft failure in male recipients of female livers, and in nonwhite recipients of orthotopic liver transplantation. United Network for Organ Sharing records of liver transplantations from 1992 through 2000 with at least one follow-up visit were reviewed. Analysis of these data was performed with proportional hazards regression, controlling for follow-up time, age, gender, ethnicity, number of comorbidities, functional status at time of transplant, and status 1 designation. Separate analyses comparing transplants among whites and blacks only and matched versus mismatched transplants for male and female recipients were performed. The results revealed that gender-mismatched patients (n = 13,992) had a higher likelihood of graft failure when compared with gender matched transplants (n = 18,522) (12.2% versus 11.3% respectively, P =.013). After controlling for the above potential confounders, gender-mismatched patients were found to have a 6.9% increase in likelihood of graft failure, (P =.042). Female recipients receiving male organs had no significant change in the risk of graft failure (11.5%; P =.368). A worse outcome was found in male recipients receiving female organs (12.9%; P =.0003). Graft failure rate among patients with donors matched by race (white to white or nonwhite to nonwhite; n = 21,818) was 11.6% versus 11.9%, and among unmatched patients (n = 10,697), the difference was not significant (P =.33). Multivariate regression analysis controlling for potential confounders confirmed that this difference was not significant (P =.21). Mismatch between black donors and white recipients was found to increase the risk of liver graft failure (27.4%, P = <.0001), independently of gender, number of comorbidities, and functional status at time of transplant.

Racial differences between solid organ transplant donors and recipients in British Columbia: a five-year retrospective analysis

BACKGROUND

We attempted to determine whether significant racial differences exist between organ donors and transplant recipients in British Columbia, and whether differences exist between individual organ transplant programs (lung, heart, kidney, liver, and pancreas). The design of the study was a retrospective review.

METHODS

We used the database of the British Columbia Transplant Society, a provincial agency, for the years 1992 to 1997 inclusive. The outcome measures were a comparison of racial characteristics of organ donors and transplant recipients collectively and by individual organ transplant program.

RESULTS

There were 236 organ donors and 766 transplant recipients. Comparing racial groups between donors and recipients, Caucasians contributed the most donors (93.2%) but received proportionately fewer organs (73.4%, P<0.000001). Orientals donated 3.4% of all organs but constituted 14.4% of all recipients (P<0.00001). Non-Oriental, non-Caucasians (predominantly Asian Indians and Native Aboriginals) constituted 3.4% of all donors and 12.2% of all recipients (P=0.0001). Among the individual organ transplant programs, lung, heart, and pancreas recipients were predominantly Caucasian (148 of 156 recipients). Oriental recipients were more likely to be kidney recipients (19.8% of all kidney recipients) compared with all Oriental recipients (P<0.000001). Likewise, Asian Indians were more likely to be kidney recipients (7.2% of all kidney recipients) compared with all Asian Indian recipients (P<0.0001). Native Aboriginals, however, were more likely to be liver allograft recipients (8.3% of all liver transplants) than nonliver allograft recipients (P=0.017).

CONCLUSIONS

In British Columbia, disparity exists between Oriental and non-Oriental, non-Caucasian donors and recipients. Orientals and Asian Indians were more likely to be kidney graft recipients than nonkidney graft recipients, whereas Native Aboriginal recipients seemed more likely to have undergone liver transplantation.