Persistent racial disparities in survival after heart transplantation

Donor Age More Than 20 Years Greater Than Recipient Age Is Associated With Worse 5-Year Survival in Young Adult Heart Transplantation

Prior studies indicate donor age-recipient age (DA-RA) difference may be of prognostic value in adolescents, although not adults. We aim to analyze the relationship between DA-RA difference and long-term survival of young adult heart transplantation (HTx) recipients. First-time, single-organ HTx recipients aged 18-30 who underwent HTx between 2010 and 2020 were analyzed from the United Network for Organ Sharing (UNOS) registry. Four cohorts were created based on DA-RA difference. The primary outcome was 5 year post-HTx survival. Secondary outcome was post-HTx complications. One thousand eight hundred three donor-recipient pairs were divided into four groups: DA-RA < 0, 0 ≤ DA-RA < 10, 10 ≤ DA-RA < 20, and DA-RA ≥ 20 with 682 (37.8%), 651 (36.1%), 356 (19.7%), 114 (6.3%) pairs in each cohort, respectively. The estimated 5 year survival of the DA-RA ≥ 20 cohort was 66.5% compared to the other three groups at ~75%. After adjustment, DA-RA ≥ 20 was independently associated with worse survival compared to DA-RA < 0 (adjusted hazard ratio [HR] = 1.55; 95% confidence interval [CI] = 1.06-2.27; log-rank p = 0.008). There was no significant difference in complication incidence across cohorts. Among young adults, accepting a donor heart more than 20 years older than the recipient was associated with worse 5 year survival. We did not detect a significant difference up to 20 years. This information may help guide appropriate donor selection in the young adult population.

Association between pre-heart transplant kidney function and post-transplant outcomes in Black and White adults

BACKGROUND

It remains unknown whether estimated glomerular filtration rate (eGFR) using the refit Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation without a term for race is associated with mortality and the need for kidney replacement therapy (KRT) differentially between Black and White heart transplant recipients.

METHODS

We studied 25,900 adults included in the Scientific Registry of Transplant Recipients. We classified recipients into six categories of eGFR (< 30, 30 to < 45, 45 to < 60, 60 to < 90, 90 to < 120, ≥ 120 ml/min/1.73 m2) using the race-neutral CKD-EPI refit equation, and assessed survival with multivariable adjusted Cox proportional hazards regression.

RESULTS

The association between pre-transplant race-neutral eGFR and mortality varied by race (Pinteraction = 0.006). Compared to White patients with an eGFR of 90-120 ml/min/1.73 m2, the mortality rates were 57% (95% CI 1.25, 1.98), 29% (95% CI 1.11, 1.51), 34% (95% CI 1.19, 1.52), and 19% (95% CI 1.06, 1.33) higher in Black patients with an eGFR less than 30, 30-45, 45-60, and 60-90 ml/min/1.73m2, respectively; and 53% (95% CI 1.28, 1.82), 49% (95% CI 1.33, 1.66), and 23% (95% CI 1.11, 1.35) higher among White patients with an eGFR less than 30, 30-45, and 45-60 ml/min/1.73 m2, respectively. The association between pre-transplant eGFR and the need for KRT during follow-up was similar between Black and White patients (Pinteraction = 0.57).

CONCLUSIONS

Worsening pre-transplant eGFR using the new race-neutral CKD-EPI refit equation was associated with a higher rate of post-heart transplant mortality and KRT in Black and White recipients. The racial disparity in post-heart transplant mortality was narrower in the setting of severe kidney dysfunction.

Racial and ethnic disparities in heart transplantation for end-stage heart failure: An analysis of the national inpatient sample (NIS) database

PURPOSE

This study aims to examine disparities among heart transplant recipients in the United States, utilizing the latest data from the National Inpatient Sample (NIS).

METHODS

We conducted a retrospective cohort analysis of NIS discharge data (2017-2020), focusing on adult end-stage heart failure (ESHF) patients, identified using the ICD-10 CM code I50.84. Our analysis included four racial groups: White, Black, Hispanic, and Asian. We employed univariable and multivariate regression analyses to determine the unadjusted and adjusted odds of heart transplantation across these racial groups, using Stata version 14.2 for statistical calculations.

RESULTS

Of 110,015 ESHF patients, 3,695 received heart transplants. Predominantly, recipients were male with a Charlson comorbidity index ≥3 and covered by private insurance. Transplants mainly occurred in large, teaching hospitals. Despite minor differences in age and median household income among races, baseline patient and hospital characteristics showed no significant variations. Compared to Whites, Blacks had a significantly lower transplant rate (AOR: 0.6; 95  % CI: 0.46-0.77; p < 0.001), while Hispanics and Asians showed no significant disparities. Mean ages varied slightly across groups (p = 0.0047), yet inpatient length of stay and hospitalization costs did not significantly differ.

CONCLUSION

Our findings highlight a significant disparity in heart transplant rates between Black and White ESHF patients in the U.S., with Black patients less likely to receive transplants compared to their White counterparts.

Advancements in Heart Transplantation: Donor-Derived Cell-Free DNA as Next-Generation Biomarker

Heart failure, particularly in its advanced stages, significantly impacts quality of life. Despite progress in Guideline-Directed Medical Therapy (GDMT) and invasive treatments, heart transplantation (HT) remains the primary option for severe cases. However, complications such as graft rejection present significant challenges that necessitate effective monitoring. Endomyocardial biopsy (EMB) is the gold standard for detecting rejection, but its invasive nature, associated risks, and healthcare costs have shifted interest in non-invasive techniques. Donor-derived cell-free DNA (dd-cfDNA) has gained attention as a promising non-invasive biomarker for monitoring graft rejection. Compared to EMB, dd-cfDNA detects graft rejection early and enables clinicians to adjust immunosuppression promptly. Despite its advantages, dd-cfDNA testing faces challenges, such as the need for specialized technology and potential inaccuracies due to other clinical conditions. Additionally, dd-cfDNA cannot yet differentiate between types of graft rejection, and its effectiveness in chronic rejection remains unclear. Research is ongoing to set precise standards for dd-cfDNA levels, which would enhance its diagnostic accuracy and help in clinical decisions. The article also points to the future of HT monitoring, which may involve combining dd-cfDNA with other biomarkers and integrating artificial intelligence to improve diagnostic capabilities and personalize patient care. Furthermore, it emphasizes both global and racial inequalities in dd-cfDNA testing and the ethical issues related to its use in transplant medicine.

Does Failure to Rescue Drive Race/Ethnicity-based Disparities in Survival After Heart Transplantation?

OBJECTIVE

The objective was to assess whether race/ethnicity is an independent predictor of failure to rescue (FTR) after orthotopic heart transplantation (OHT).

SUMMARY BACKGROUND DATA

Outcomes following OHT vary by patient level factors; for example, non-White patients have worse outcomes than White patients after OHT. Failure to rescue is an important factor associated with cardiac surgery outcomes, but its relationship to demographic factors is unknown.

METHODS

Using the United Network for Organ Sharing database, we included all adult patients who underwent primary isolated OHT between 1/1/2006 snd 6/30/2021. FTR was defined as the inability to prevent mortality after at least one of the UNOS-designated postoperative complications. Donor, recipient, and transplant characteristics, including complications and FTR, were compared across race/ethnicity. Logistic regression models were created to identify factors associated with complications and FTR. Kaplan Meier and adjusted Cox proportional hazards models evaluated the association between race/ethnicity and posttransplant survival.

RESULTS

There were 33,244 adult, isolated heart transplant recipients included: the distribution of race/ethnicity was 66% (n=21,937) White, 21.2% (7,062) Black, 8.3% (2,768) Hispanic, and 3.3% (1,096) Asian. The frequency of complications and FTR differed significantly by race/ethnicity. After adjustment, Hispanic recipients were more likely to experience FTR than White recipients (OR 1.327, 95% CI[1.075-1.639], P =0.02). Black recipients had lower 5-year survival compared with other races/ethnicities (HR 1.276, 95% CI[1.207-1.348], P <0.0001).

CONCLUSIONS

In the US, Black recipients have an increased risk of mortality after OHT compared with White recipients, without associated differences in FTR. In contrast, Hispanic recipients have an increased likelihood of FTR, but no significant mortality difference compared with White recipients. These findings highlight the need for tailored approaches to addressing race/ethnicity-based health inequities in the practice of heart transplantation.

Achieving Health Equity in the Care of Patients with Heart Failure

PURPOSE OF REVIEW

To discuss the prevailing racial and ethnic disparities in heart failure (HF) care by identifying barriers to equitable care and proposing solutions for achieving equitable outcomes.

RECENT FINDINGS

Throughout the entire spectrum of HF care, from prevention to implementation of guideline-directed medical therapy and advanced interventions, racial and ethnic disparities exist. Factors such as differential distribution of risk factors, poor access to care, inadequate representation in clinical trials, and discrimination from healthcare clinicians, among others, contribute to these disparities. Recent data suggests that despite improvements, disparities prevail in several aspects of HF care, hindering our progress towards equity in HF care. This review highlights the urgent need to address racial and ethnic disparities in HF care, emphasizing the importance of a multifaceted approach involving policy changes, quality improvement strategies, targeted interventions, and intentional community engagement. Our proposed framework was derived from existing research and emphasizes integrating equity into routine quality improvement efforts, tailoring interventions to specific populations, and advocating for policy transformation. By acknowledging these disparities, implementing evidence-based strategies, and fostering collaborative efforts, the HF community can strive to reduce disparities and achieve equity in HF care.

Importance of social vulnerability on long-term outcomes after heart transplantation

The relationship between social determinants of health and outcomes after heart transplantation has not been examined. The social vulnerability index (SVI) uses United States census data to determine the social vulnerability of every census tract based on 15 factors. This retrospective study seeks to examine the impact of SVI on outcomes after heart transplantation. Adult heart recipients who received a graft between 2012 and 2021 were stratified into SVI percentiles of <75% and SVI of ≥75%. The primary endpoint was survival. The median SVI was 48% (interquartile range: 30%-67%) among 23 700 recipients. One-year survival was similar between groups (91.4 vs 90.7%, log-rank P = .169); however, 5-year survival was lower among individuals living in vulnerable communities (74.8% vs 80.0%, P < .001). This finding persisted despite risk adjustment for other factors associated with mortality (survival time ratio 0.819, 95% confidence interval: 0.755-0.890, P < .001). The incidences of 5-year hospital readmission (81.4% vs 75.4%, P < .001) and graft rejection (40.3% vs 35.7%, P = .004) were higher among individuals living in vulnerable communities. Individuals living in vulnerable communities may be at increased risk of mortality after heart transplantation. These findings suggest there is an opportunity to focus on these recipients undergoing heart transplantation to improve survival.

Racial and Ethnic Disparities in U.S Children Undergoing Surgery for Congenital Heart Disease: A Narrative Literature Review

Congenital Heart Disease (CHD) is a significant source of pediatric morbidity and mortality. As in other fields of medicine, studies have demonstrated racial and ethnic disparities in congenital heart disease outcomes. The cause of these outcome disparities is multifactorial, involving biological, behavioral, environmental, sociocultural, and systemic medical factors. Potential contributors include differences in preoperative illness severity secondary to coexisting medical conditions, differences in the rate of prenatal and early postnatal detection of CHD, and delayed access to care, as well as discrepancies in socioeconomic and insurance status, and systemic disparities in hospital care. Understanding the factors that contribute to these disparities is an essential step towards developing strategies to address them. As stewards of the perioperative surgical home, anesthesiologists have an important role in developing institutional policies that mitigate racial disparities. Here, we provide a thorough narrative review of recent research concerning perioperative factors contributing to surgical outcomes disparities for children of all ages with CHD, examine potentially modifiable contributing factors, discuss avenues for future research, and suggest strategies to address disparities both locally and nationally.

Extracorporeal membrane oxygenation bridge to pediatric lung transplantation: Modern era analysis

BACKGROUND

Survival outcomes of children on extracorporeal membrane oxygenation (ECMO) at time of lung transplant (LTx) remain unclear.

METHODS

Pediatric first-time LTx recipients transplanted between January 2000 and December 2020 were identified in the United Network for Organ Sharing Registry to compare post-transplant survival according to ECMO support at time of transplant. For a comprehensive analysis of the data, univariate analysis, multivariable Cox regression, and propensity score matching were performed.

RESULTS

During the study period, 954 children under 18 years of age underwent LTx with 40 patients on ECMO. We did not identify a post-LTx survival difference between patients receiving ECMO when compared to those that did not. A multivariable Cox regression model (Hazard ratio = 0.83; 95% confidence interval: 0.47, 1.45; p = .51) did not demonstrate an increased risk for death post-LTx. Lastly, a propensity score matching analysis, retaining 33 ECMO and 33 non-ECMO patients, further confirmed no post-LTx survival difference comparing ECMO to no ECMO cohorts (Hazard ratio = 0.98; 95% confidence interval: 0.48, 2.00; p = .96).

CONCLUSIONS

In this contemporary cohort of children, the use of ECMO at the time of LTx did not negatively impact post-transplant survival.

Temporal trends in primary payers in pediatric heart transplant and association with long-term survival

BACKGROUND

Pediatric heart transplantation (HT) is resource intensive. In adults, there has been an increase in the proportion of HTs funded by public insurance, with post-HT outcomes inferior to those funded by private sources. Trends in the funding of pediatric HT and outcomes in children have not been described.

METHODS

We queried the United Network for Organ Sharing (UNOS) database for children (<18 years) listed for and undergoing HT between 2004 and 2021. We identified the primary payer at listing, HT, 1 year, and 1-5 years following HT. Trends were analyzed using generalized logit models. Multivariable-extended Cox regression models were used to test the relationship between insurance type at the time of transplant and time to death or re-transplant.

RESULTS

There were 6382 pediatric patients who underwent transplants and had either public or private insurance at the time of transplant. The percentage of patients with public insurance at the time of HT increased over time. Public insurance at the time of HT was associated with an increased risk of death or re-transplant beyond 2 months after HT (adjusted HR at 6 months = 1.43, 95% CI: 1.13-1.81, p = .003; adjusted HR at 9 months = 1.67, 95% CI: 1.17-2.37, p = .004).

CONCLUSION

There has been a statistically significant trend toward increasing public insurance for children awaiting, at the time of, and after HT. Black patients and those with public insurance at HT have worse long-term outcomes. This study highlights ongoing disparities in pediatric HT and the need to focus efforts on achieving equitable outcomes.

Improvement in Racial Disparities in Heart Transplantation following the Heart Allocation Policy Change

Objectives. Heart transplantation (HT) is a definitive therapy for refractory heart failure, making it the gold-standard treatment for recipients with end-stage disease. Heart allocation policy (HAP) in the United States was changed on October 18th, 2018. The aim of this study was to assess the effect of the new policy on racial disparities in heart transplantation (HT) outcomes. Methods. The United Network for Organ Sharing (UNOS) registry was used to identify adult recipients undergoing isolated HT between 2010 and 2021. Recipients were stratified into pre-HAP (January 2010 to September 2018) vs. post-HAP (October 2018 to September 2021). Recipient race was classified as White, Black, Hispanic, or other. The primary outcome was post-HT mortality. Cox proportional hazard models were used for risk-adjustment in evaluating the independent effect of race on post-HT mortality. Results. A total of 27,403 recipients underwent HT in 143 centers during study period. The proportion of non-Whites undergoing HT increased in the post-HAP era: (pre-HAP: White 66.0%, Black 21.2%, Hispanic 8.2%, Other 4.6% versus post-HAP: White 62.5%, Black 23.2%, Hispanic 9.5%, Other 4.8%; $p<0.001$ ). In risk-adjusted analysis, Black recipients were at higher risk of post-HT mortality in the pre-HAP era (HR 1.31, 95% CI 1.22–1.41; $p<0.001$ ) but not in the post-HAP era (HR 1.12, 95% CI 0.03–1.34; $p=0.222$ ) compared to White recipients. Other non-White recipients had comparable risk-adjusted post-HT mortality rates compared to White recipients both in the pre-HAP and post-HAP eras. Conclusions. Under the new heart allocation system, a higher percentage of recipients are non-White. In addition, racial disparities in HT outcomes have improved with Black recipients no longer having an increased risk-adjusted mortality following HT.

Racial disparities in post-transplant stroke and mortality following stroke in adult cardiac transplant recipients in the United States

Black heart transplant recipients have a higher mortality rate than white recipients 6-12 months after transplant. Whether there are racial disparities in post-transplant stroke incidence and all-cause mortality following post-transplant stroke among cardiac transplant recipients is unknown. Using a nationwide transplant registry, we assessed the association between race and incident post-transplant stroke using logistic regression and the association between race and mortality among adults who survived a post-transplant stroke using Cox proportional hazards regression. We found no evidence of an association between race and the odds of post-transplant stroke (OR = 1.00, 95% CI: 0.83-1.20). The median survival time of those with a post-transplant stroke in this cohort was 4.1 years (95% CI: 3.0, 5.4). There were 726 deaths among the 1139 patients with post-transplant stroke, including 127 deaths among 203 Black patients and 599 deaths among 936 white patients. Among post-transplant stroke survivors, Black transplant recipients experienced a 23% higher rate of mortality compared to white recipients (HR = 1.23, 95% CI: 1.00-1.52). This disparity is strongest in the period beyond the first 6 months and appears to be mediated by differences in the post-transplant setting of care between Black and white patients. The racial disparity in mortality outcomes was not evident in the past decade. The improved survival of Black patients in the recent decade may reflect overall protocol improvements for heart transplant recipients irrespective of race, such as advancements in surgical techniques and immediate postoperative care as well as increased awareness about reducing racial disparities.

Impact of race and health coverage on listing and waitlist mortality in pediatric cardiac transplantation

BACKGROUND

Social factors like race and insurance affect transplant outcomes. However, little is known in pediatric heart transplantation. We hypothesized that race and insurance coverage impact listing and waitlist outcomes across eras.

METHODS

Data from the Pediatric Heart Transplant Society multi-center registry prospectively collected between January 1, 2000-December 31, 2019 were analyzed. Patients were divided by race as Black, White and other and by insurance coverage at listing (US governmental, US private and non-US single payer systems (UK, Canada). Clinical condition at listing and waitlist outcomes were compared across races and insurance coverages. Categorical variables were compared using a chi-square test and continuous variables using the Wilcoxon rank sum test. Risk factors for waitlist mortality were examined using multiphase parametric hazard modeling. A sensitivity analysis using parametric hazard explored the interaction between race and insurance.

RESULTS

At listing, compared to Whites (n = 5391) and others (n = 1167), Black patients (n = 1428) were older, more likely on US governmental insurance and had cardiomyopathy as the predominant diagnosis (p < 0.0001). Black patients were more likely to be higher status at listing, in hospital, on inotropes or a ventricular assist device (p < 0.0001). Black patients had significantly shorter time on the waitlist compared to other races (p < 0.0001) but had higher waitlist mortality (p = 0.0091), driven by the earlier era (2000-2009) (p = 0.0005), most prominently within the US private insurance cohort (p = 0.015). Outcomes were not different in other insurance cohorts or in the recent era (2010-2019).

CONCLUSION

Black children are older and sicker at the time of listing, deteriorate more often and face a higher wait list mortality, despite a shorter waitlist period and favorable clinical factors, with improvement in the recent era associated with the recent US healthcare reforms. The social construct of race appears to disadvantage Black children by limiting referral, consideration or access to pediatric cardiac transplantation.

Post-transplant mortality and graft failure after induction immunosuppression among Black heart transplant recipients in the United States

Black heart transplant recipients are more likely to receive induction immunosuppression compared to other races because of higher rates of acute rejection, graft failure, and mortality. However, it is not known whether contemporary induction immunosuppression improves their post-transplant outcomes. To evaluate whether Black patients who were prescribed induction immunosuppression therapy have lower all-cause mortality or graft-failure rates compared to those who were not, we studied Black U.S. adult heart transplant recipients in the Scientific Registry of Transplant Recipients database (2008-2018). We used multivariable Cox proportional hazards regression analysis to compare the hazards of all-cause mortality or graft failure as a composite, for patients who were prescribed induction immunosuppression and those who were not. Among 5160 recipients, 2787 (54.0%) were prescribed induction immunosuppression and 2373 (46.0%) were not. There was no evidence of survival differences according to induction immunosuppression for the composite of all-cause mortality or graft failure (aHR = 1.13, 95% CI 0.96-1.32), mortality (aHR = 1.14, 95% CI 0.97-1.34), graft failure (aHR = 1.05, 95% CI 0.82-1.34) and acute rejection (aHR = 1.00, 95% CI 0.89-1.12). Given the side effects of treatment, future guidelines should reconsider the recommendation for induction immunosuppression among Black patients.

Racial Disparities in Coronavirus Disease 2019 Mortality Are Present in Heart Transplant Recipients

BACKGROUND

Studies have demonstrated the devastating effects of coronavirus disease 2019 (COVID-19) on vulnerable populations. Although they receive close follow-up, heart transplant recipients represent a particularly vulnerable population, given long-term immunosuppression and comorbid conditions. We sought to investigate the association between race/ethnicity and the probability of death due to COVID-19 in adult heart transplant recipients in the United States.

METHODS

Adult isolated heart transplant recipients were identified using the Organ Procurement and Transplantation Network database. Recipients who were described as deceased or lost to follow-up before January 2020 were excluded. Recipients were stratified into 4 cohorts by race/ethnicity. The primary outcome of interest was death due to COVID-19.

RESULTS

A total of 22 157 adult recipients were identified. During the course of follow-up, 153 recipients had COVID-19 reported as the primary cause of death. COVID-19 mortality was significantly different between race/ethnicity cohorts (Black, n = 34 [0.79%]; Hispanic, n = 23 [1.33%]; White, n = 92 [0.60%]; other, n = 4 [0.44%]; P = .007). COVID-19 was listed as a contributing cause of mortality in 0.12% of Black, 0.23% of Hispanic, 0.04% of White, and 0.33% of other recipients (P = .002). No significant difference in non-COVID mortality or all-cause mortality was observed. After multivariable adjustment, Black (hazard ratio, 2.78 [1.40-5.52]; P = .003) and Hispanic (hazard ratio, 3.92 [1.88-8.16]; P < .001) recipients were at higher risk of death due to COVID-19 compared with White recipients.

CONCLUSIONS

Compared with White recipients, Black and Hispanic recipients experienced higher rates of COVID-19 mortality after transplantation. These findings suggest that racial/ethnic disparities of COVID-19 mortality in the general population persist in adult heart transplant recipients.

Recipient-surgeon racial concordance in orthotopic heart transplantation outcomes

BACKGROUND

Prior studies have demonstrated deleterious outcomes for physician-patient racial discordance. We explored recipient-surgeon racial concordance and short-term postoperative survival in adults undergoing orthotopic heart transplantation (OHT).

METHODS

The United Network for Organ Sharing (UNOS) database was queried to identify White and Black adult (≥18 years) patients undergoing isolated OHT between 2000 and 2020. Surgeon race was obtained from publicly available images. All non-White and non-Black recipients and surgeons were excluded. Linear probability models were utilized to explore the relationship between recipient-surgeon racial concordance and 30-, 60-, and 90-day post-transplant mortality using a fixed effects approach.

RESULTS

A total of 26,133 recipients were identified (mean age 52.79 years, 74.4% male) with 77.65% (n = 20,292) being White and 22.35% (n = 5841) being Black. A total of 662 White surgeons performed 25,946 (97.56%) OHTs during the study period while 17 Black surgeons performed 437 (1.67%) OHTs. Although some evidence of differences across groups was observed in cross-tabular specifications, these differences became insignificant after the inclusion of controls (i.e., comorbidities and fixed effects). This suggests that recipient race and physician race are not correlated with post-OHT survival at 30, 60, or 90 days.

CONCLUSIONS

Recipient-surgeon racial concordance and discordance among adults undergoing OHT do not appear to impact post-transplant survival. Nor do we observe significant penalties accruing for Black patients overall once controls are accounted for. Given that worse outcomes have historically been demonstrated for Black patients undergoing OHT, further work will be necessary to improve understanding of racial disparities for patients with end-stage heart failure.

Racial disparities in cardiac transplantation: Chronological perspective and outcomes

BACKGROUND

The objective of this study was to evaluate annual heart transplant volumes and 3-year post-transplant outcomes since establishment of United Network for Organ Sharing (UNOS) database stratified by race.

METHODS

The UNOS thoracic transplant database was evaluated for adult patients since 1987. The available database was then stratified by Race: Black, White and Other and era of transplant: group 1(1987-1991), group 2(1992-1996), group 3(1997-2001), group 4(2002-2006), group 5(2007-2011), group 6(2012-2016) and group 7(2017 and later). Demographic and clinical factors were evaluated.

RESULTS

A total of 105,266 adults have been listed since 1987 and 67,824 have been transplanted. Of the transplanted patients 11,235 were Black, 48,786 White and 6803 were of Other race. The proportion of Black patients listed increased from 7% in 1987 to 13.4% in 1999 and 25% in 2019 and those transplanted increased from 5% in 1987 to 13.4% in 2001 and 26% in 2019. The survival of Black patients gradually improved.

CONCLUSION

Historically, fewer Black patients received cardiac transplantation however, their access gradually improved over the years and account for over 25% of cardiac transplantations performed in recent years. The historically poor survival of Black patients has recently improved and became comparable to the rest.

Disparities in heart and lung transplantation

PURPOSE OF REVIEW

Cardiothoracic transplantation is the definitive therapy for end-stage heart and lung disease. In service to this population, disparities in access and care must be simultaneously understood and addressed.

RECENT FINDINGS

There are sex, race, geographic, age, and underlying disease disparities in both heart and lung transplantation. Women have reduced waitlist survival but improved posttransplant survival when compared with men for both heart and lung transplantation. Black patients have worse outcome compared with other races postheart transplant. Geographic disparities impact the likelihood of receiving heart or lung transplant and the growing number of patients with advanced age seeking transplant complicates discussions on survival benefit. Finally, underlying disease has affected outcomes for both heart and lung transplant and now are incorporated into the allocation system.

SUMMARY

Though heart and lung transplantation have several existing disparities, it remains to be seen how advancements in medical technology, changes in donor organ allocation policies, and growing experience in patient selection will impact these concerns.

Evaluation of Racial and Ethnic Disparities in Cardiac Transplantation

Background Racial and ethnic disparities contribute to differences in access and outcomes for patients undergoing heart transplantation. We evaluated contemporary outcomes for heart transplantation stratified by race and ethnicity as well as the new 2018 allocation system. Methods and Results Adult heart recipients from 2011 to 2020 were identified in the United Network for Organ Sharing database and stratified into 3 groups: Black, Hispanic, and White. We analyzed recipient and donor characteristics, and outcomes. Among 32 353 patients (25% Black, 9% Hispanic, 66% White), Black and Hispanic patients were younger, more likely to be women and have diabetes mellitus or renal disease (all, P<0.05). Over the study period, the proportion of Black and Hispanic patients listed for transplant increased: 21.7% to 28.2% (P=0.003) and 7.7% to 9.0% (P=0.002), respectively. Compared with White patients, Black patients were less likely to undergo transplantation (adjusted hazard ratio [aHR], 0.87; CI, 0.84-0.90; P<0.001), but had a higher risk of post-transplant death (aHR, 1.14; CI, 1.04-1.24; P=0.004). There were no differences in transplantation likelihood or post-transplant mortality between Hispanic and White patients. Following the allocation system change, transplantation rates increased for all groups (P<0.05). However, Black patients still had a lower likelihood of transplantation than White patients (aHR, 0.90; CI, 0.79-0.99; P=0.024). Conclusions Although the proportion of Black and Hispanic patients listed for cardiac transplantation have increased, significant disparities remain. Compared with White patients, Black patients were less likely to be transplanted, even with the new allocation system, and had a higher risk of post-transplantation death.

Cardiac transplantation outcomes in patients with amyloid cardiomyopathy

OBJECTIVE

Amyloid cardiomyopathy (ACM) is a progressive and life-threatening disease caused by abnormal protein deposits within cardiac tissue. The most common forms of ACM are caused by immunoglobulin derived light chains (AL) and transthyretin (TTR). Orthotopic heart transplantation (OHT) remains the definitive treatment for patients with end stage heart failure. In this study, we perform a contemporary multicenter analysis evaluating post OHT survival in patients with ACM.

METHODS

We conducted a multicenter analysis of 40,044 adult OHT recipients captured in the United Network for Organ Sharing (UNOS) registry from 1987-2018. Patients were characterized as ACM or non-ACM. Baseline characteristics were obtained, and summary characteristics were calculated. Outcomes of interest included post-transplant survival, infection, treated rejection, and the ability to return to work. Racial differences in OHT survival were also analyzed. Unadjusted associations between ACM and non-ACM survival were determined using the Kaplan-Meier estimations and confounding was addressed using multivariable Cox proportional hazards models.

RESULTS

Three hundred ninety-eight patients with a diagnosis of ACM were identified of which 313 underwent heart only OHT. ACM patients were older (61 vs 53; P < .0001) and had a higher proportion of African Americans (30.7% vs 17.6%; P < .0001). Median survival for ACM was 10.2 years vs 12.5 years in non-ACM (P = .01). After adjusting for confounding, ACM patients had a higher likelihood of death post-OHT (HR 1.39 CI: 1.14, 1.70; P = .001). African American ACM patients had a higher likelihood of survival compared to White ACM patients (HR 0.51 CI 0.31-0.85; P = .01). No difference was observed in episodes of treated rejection (OR 0.63 CI 0.23, 1.78; P = .39), hospitalizations for infections (OR 1.24 CI: 0.85, 1.81; P = .26), or likelihood of returning to work for income (OR 1.23 CI: 0.84, 1.80; P = .30).

CONCLUSIONS

In this analysis of OHT in ACM, ACM was associated with a higher likelihood of post-OHT mortality. Racial differences in post-OHT were observed with African American patients with ACM having higher likelihood of survival compared to White patients with ACM. No differences were observed in episodes of treated rejection, hospitalization for infection, or likelihood to return to work for income.

Racial differences in outcomes after receiving advanced heart failure therapies

PURPOSE OF REVIEW

Despite advances in medical and device-based therapies for advanced heart failure as well as public policy, disparities by race/ethnicity persist in heart failure clinical outcomes. The purpose of this review is to describe disparities in outcomes by race--ethnicity in patients after receipt of heart transplantation and left ventricular assist device (LVAD), and the current understanding of factors contributing to these disparities.

RECENT FINDINGS

The proportion of black and Latinx patients receiving advanced heart failure therapies continues to rise, and they have worse hemodynamic profiles at the time of referral for heart transplantation and LVAD. Black patients have lower rates of survival after heart transplantation, in part because of higher rates of cellular and humoral rejection that may be mediated through unique gene pathways, and increased risk for allosensitization and de-novo donor-specific antibodies. Factors that have previously been cited as reasons for worse outcomes in race--ethnic minorities, including psychosocial risk and lower SES, may not be as strongly correlated with outcomes after LVAD.

SUMMARY

Black and Latinx patients are sicker at the time of referral for advanced heart failure therapies. Despite higher psychosocial risk factors among race--ethnic minorities, outcomes after LVAD appear to be similar to white patients. Black patients continue to have lower posttransplant survival, because of a complex interplay of immunologic susceptibility, clinical and socioeconomic factors. No single factor accounts for the disparities in clinical outcomes for race--ethnic minorities, and thus consideration of these components together is critical in management of these patients.

The effects of increased donor support time from organ donation referral to donor procurement on heart transplant recipient survival

INTRODUCTION

Given the known deleterious cardiac effects of brain death (BD) physiology, we hypothesized that time from cardiac donation referral to procurement (donor support time [DST]), would negatively impact cardiac transplant recipient survival.

METHODS

The United Network for Organ Sharing database was queried from 2007 to 2018, identifying 22,593 donor hearts for analysis. Multivariate logistic models for 30-day and 1-year survival, as well as Cox models for overall survival and posttransplant rejection, were used to assess adjusted outcomes.

RESULTS

median DST was 3 days (interquartile range: 2-5 days). Ischemic time; distance between donor and recipient hospitals; and recipient age, creatinine, waitlist time, and length of stay were adjusted predictors of survival and rejection. DST was not associated with either outcome in aggregate; however, differential association by donor race was identified, with DST in any race recipient associated with 4% higher odds of 1-year mortality (p = .001; p value for interaction .005) but only a trend towards worse overall mortality (p = .064; p value for interaction .046).

CONCLUSION

Thus, duration of exposure to BD physiology may have a differential impact on recipient outcomes based on donor race, suggesting that additional research is needed on donor immunologic, socioeconomic, and healthcare access factors that may impact cardiac transplant recipient outcomes.

Better Understanding the Disparity Associated With Black Race in Heart Transplant Outcomes: A National Registry Analysis

BACKGROUND

Black heart transplant recipients have higher risk of mortality than White recipients. Better understanding of this disparity, including subgroups most affected and timing of the highest risk, is necessary to improve care of Black recipients. We hypothesize that this disparity may be most pronounced among young recipients, as barriers to care like socioeconomic factors may be particularly salient in a younger population and lead to higher early risk of mortality.

METHODS

We studied 22 997 adult heart transplant recipients using the Scientific Registry of Transplant Recipients data from January 2005 to 2017 using Cox regression models adjusted for recipient, donor, and transplant characteristics.

RESULTS

Among recipients aged 18 to 30 years, Black recipients had 2.05-fold (95% CI, 1.67-2.51) higher risk of mortality compared with non-Black recipients (P<0.001, interaction P<0.001); however, the risk was significant only in the first year post-transplant (first year: adjusted hazard ratio, 2.30 [95% CI, 1.60-3.31], P<0.001; after first year: adjusted hazard ratio, 0.84 [95% CI, 0.54-1.29]; P=0.4). This association was attenuated among recipients aged 31 to 40 and 41 to 60 years, in whom Black recipients had 1.53-fold ([95% CI, 1.25-1.89] P<0.001) and 1.20-fold ([95% CI, 1.09-1.33] P<0.001) higher risk of mortality. Among recipients aged 61 to 80 years, no significant association was seen with Black race (adjusted hazard ratio, 1.12 [95% CI, 0.97-1.29]; P=0.1).

CONCLUSIONS

Young Black recipients have a high risk of mortality in the first year after heart transplant, which has been masked in decades of research looking at disparities in aggregate. To reduce overall racial disparities, clinical research moving forward should focus on targeted interventions for young Black recipients during this period.

Impacts of social inequalities on the survival of heart transplant recipients in a developing country

BACKGROUND

Heart transplant (HT) is an alternative for patients with advanced heart failure (HF). Social inequalities may influence survival, but are still not well understood. The aim of this study was to assess the impact of social and clinical inequalities on the survival of HT recipients.

METHODS

Retrospective cohort study conducted at a Brazilian hospital from 2006 to 2018.

RESULTS

Three hundred and two patients were analyzed. Most HT recipients were male (205, 67.9%), mixed race 146 (48.3%), retired (166, 56.5%), median age 47 (38-57) years, and had studied no more than eight years (191, 65.8%), were younger than 60 years old (256, 84.7%). 149 (51.7%) had per capita monthly income inferior to one Brazilian minimum wage, equivalent to US$250. 123 (95.4%) out of 129 patients had allograft cellular rejection 2R or 3R. Median donor age was 32 (23-39) years. The overall survival was 76.6%, 62.2%, and 58.2%, at 1, 5, and 10 years, respectively. Age <60 years old and higher income were associated with a greater chance of survival (p-values .009 and <.001, respectively).

CONCLUSION

Younger age and higher per capita income had positive impact on HT recipient survival. The level of education did not affect survival in this cohort.

Increased Incidence of Chronic Kidney Injury in African Americans Following Cardiac Transplantation

OBJECTIVES

This study examined whether African American race was associated with an elevated risk of chronic kidney disease (CKD) post-cardiac transplantation.

BACKGROUND

CKD often occurs after cardiac transplantation and may require renal replacement therapy (RRT) or renal transplant. African American patients have a higher risk for kidney disease as well as worse post-cardiac transplant morbidity and mortality. It is unclear, however, if there is a propensity for African Americans to develop CKD after cardiac transplant.

METHODS

The Institutional Review Board of Columbia University Medical Center approved the retrospective study of 151 adults (57 African American and 94 non-African American) who underwent single-organ heart transplant from 2013 to 2016. The primary outcome was a decrease in estimated glomerular filtration rate (eGFR), development of CKD, and end-stage renal disease (ESRD) requiring RRT after 2 years.

RESULTS

African American patients had a significant decline in eGFR post-cardiac transplant compared to non-African American patients (- 34 ± 6 vs. - 20 ± 4 mL/min/1.73 m2, p < 0.0006). African American patients were more likely to develop CKD stage 2 or worse (eGFR < 90 mL/min/1.73 m2) than non-African American patients (81% vs. 59%, p < 0.0005).

CONCLUSIONS

This is the first study to report that African American patients are at a significantly higher risk for eGFR decline and CKD at 2 years post-cardiac transplant. Future investigation into risk reduction is necessary for this patient population.

Hypogammaglobulinemia following heart transplantation: Prevalence, predictors, and clinical importance

Hypogammaglobulinemia (HGG) can occur following solid organ transplantation. However, there are limited data describing the prevalence, risk factors, and clinical outcomes associated with HGG following heart transplantation. We retrospectively reviewed data of 132 patients who had undergone heart transplantation at our institution between April 2014 and December 2018. We classified patients into three groups based on the lowest serum IgG level post-transplant: normal (≥700 mg/dL), mild HGG (≥450 and <700 mg/dL), and severe HGG (<450 mg/dL). We compared clinical outcomes from the date of the lowest IgG level. Mean age was 57 (47, 64) years, and 94 (71%) patients were male. Prevalence of severe HGG was the highest (27%) at 3-6 months following heart transplantation and then decreased to 5% after 1 year. Multivariate analysis showed that older age and Caucasian race were independent risk factors for HGG. Overall survival was comparable between the groups; however, survival free of infection was 73%, 60%, and 45% at 1 year in the normal, mild HGG, and severe HGG groups, respectively (P = .013). In conclusion, there is a high prevalence of HGG in the early post-heart transplant period that decreases over time. HGG is associated with an increased incidence of infection.

Long-Term Survival After Heart Transplantation at Centers Stratified by Short-Term Performance

BACKGROUND

Center differences in short-term survival after heart transplant (HT) are known. We sought to compare long-term graft survival (freedom from death or retransplantation) at currently active United States HT centers stratified by performance for short-term survival.

METHODS

We used the Organ Procurement and Transplant Network database to identify subjects ≥18 years old who received primary HT during 2000 to 2014 at US centers active during 2013 and 2014. Follow-up was available until March 2016. Center case-mix was assessed by computing expected 90-day mortality and short-term performance by 90-day standardized mortality ratio (SMR; observed/expected mortality). Centers were stratified by case-mix as transplanting low-, intermediate-, and high-risk patients and by short-term performance as SMR quintiles. Center-level differences in long-term graft survival were assessed by risk-adjusted, mixed-effects Weibull survival models with center as a random effect.

RESULTS

We analyzed 25 467 HT recipients at 96 centers. Those receiving HT at centers with superior (lower) 90-day SMR had longer graft survival (P for trend <0.001). Survival difference among SMR groups remained significant in 90-day conditional survivors (P for trend <0.001). There was significant center-level variation in risk-adjusted graft survival censored at 5 years (P<0.001) and with all follow-up (P<0.001). Adjusting for 90-day SMR was associated with 62% reduction in center variation in 5-year graft survival and 56% reduction in center variation in overall graft survival.

CONCLUSIONS

HT recipients at centers with superior short-term outcomes have longer graft survival on long-term follow-up. Allocating resources to improve patient care processes and transplant expertise at high-SMR centers may improve short-term and overall survival after HT.

Ethnic disparity in Israel impacts long-term results after heart transplantation

BACKGROUND

Ethnicity may affect graft longevity and recipient mortality after heart transplantation (HTx). We hypothesized that differences in ethnic origin between Arabs and Jews undergoing HTx in Israel may contribute to differences in long-term outcomes.

METHODS

The study population comprised all 254 patients who underwent HTx between 1991 and 2017 in a tertiary medical center located in the center of Israel. Patients were categorized as either Jews (226 patients, 89%) or Arabs (28 patients, 11%). The primary end point was cardiac allograft vasculopathy (CAV), secondary end points were cardiovascular (CV) mortality and the combined end point of CAV/CV mortality.

RESULTS

In comparison with Jews, Arab patients were significantly younger (ave. age 42 vs. 50) and had shorter in-hospital stay (45 vs. 80 days). However, Kaplan-Meier survival analysis showed that at 10 years of follow-up CAV rates were significantly higher among Arabs (58%) compared with Jews (23%; log-rank P = 0.01) for the overall difference during follow-up. Similar results were shown for the separate end point of CV mortality and the combined end point of CAV/CV mortality. Multivariate analysis, which controlled for age, gender, statin treatment, and other potential confounders, showed that Arab recipient ethnic origin was associated with a significant > 2.5-fold (p = 0.01) increase in the risk for CAV; a > 4-fold increase in the risk for CV mortality (p = 0.001); and approximately 4-fold increase in the risk for the combined end point (p = 0.001). These findings were validated by propensity score analysis.

CONCLUSIONS

Our data suggest that Arab ethnic origin is associated with a significantly increased risk for CAV and mortality following HTx. Suggested explanations contributing to ethnic disparities in Israel include socioeconomic, environmental and genetic factors. Further studies are required to evaluate whether more aggressive risk factor management in the Israeli Arab population following HTx would reduce CAV and CV mortality in this high-risk population. Increased awareness and early intervention of the Israeli healthcare system and cooperation with the Arab community is of paramount importance.

Risk evaluation using gene expression screening to monitor for acute cellular rejection in heart transplant recipients

BACKGROUND

Gene expression profiling (GEP) was developed for non-invasive surveillance of acute cellular rejection. Despite its widespread use, there has been a paucity in outcome data for patients managed with GEP outside of clinical trials.

METHODS

The Outcomes AlloMap Registry (OAR) is an observational, prospective, multicenter study including patients aged ≥ 15 years and ≥ 55 days post-cardiac transplant. Primary outcome was death and a composite outcome of hemodynamically significant rejection, graft dysfunction, retransplantation, or death. Secondary outcomes included readmission rates and development of coronary allograft vasculopathy and malignancies.

RESULTS

The study included 1,504 patients, who were predominantly Caucasian (69%), male (74%), and aged 54.1 ± 12.9 years. The prevalence of moderate to severe acute cellular rejection (≥2R) was 2.0% from 2 to 6 months and 2.2% after 6 months. In the OAR there was no association between higher GEP scores and coronary allograft vasculopathy (p = 0.25), cancer (p = 0.16), or non-cytomegalovirus infection (p = 0.10). Survival at 1, 2, and 5 years post-transplant was 99%, 98%, and 94%, respectively. The composite outcome occurred in 103 patients during the follow-up period. GEP scores in dual-organ recipients (heart-kidney and heart-liver) were comparable to heart-alone recipients.

CONCLUSIONS

This registry comprises the largest contemporary cohort of patients undergoing GEP for surveillance. Among patients selected for GEP surveillance, survival is excellent, and rates of acute rejection, graft dysfunction, readmission, and death are low.

Socioeconomic Disparities in Adherence and Outcomes After Heart Transplant: A UNOS (United Network for Organ Sharing) Registry Analysis

BACKGROUND

There is mixed evidence of racial and socioeconomic disparities in heart transplant outcomes. Their underlying cause-and whether individual- or community-level traits are most influential-remains unclear. The current study aimed to characterize socioeconomic disparities in outcomes and identify time trends and mediators of these disparities.

METHODS AND RESULTS

We used United Network for Organ Sharing registry data and included 33 893 adult heart transplant recipients between 1994 and 2014. Socioeconomic status (SES) indicators included insurance, education, and neighborhood SES measured using a composite index. Black race and multiple indicators of low SES were associated with the primary outcome of death or retransplant, independent of baseline clinical characteristics. Blacks had lower HLA and race matching, but further adjustment for these and other graft characteristics only slightly attenuated the association with black race (HR, 1.25 after adjustment). This and the associations with neighborhood SES (HR, 1.19 for lowest versus highest decile), Medicare (HR, 1.17), Medicaid (HR, 1.29), and college education (HR, 0.90) remained significant after full adjustment. When comparing early (1994-2000) and late (2001-2014) cohorts, the disparities associated with the middle (second and third) quartiles significantly decreased over time, but those associated with lowest SES quartile and black race persisted. Low neighborhood SES was also associated with higher risks of noncompliance (HR, 1.76), rejection (HR, 1.28), hospitalization (HR, 1.13), and infection (HR, 1.10).

CONCLUSIONS

Racial and socioeconomic disparities exist in heart transplant outcomes, but the latter may be narrowing over time. These disparities are not explained by differences in clinical or graft characteristics.

Assessment of Heart Transplant Waitlist Time and Pre- and Post-transplant Failure: A Mixed Methods Approach

BACKGROUND

Over the past two decades, there have been increasingly long waiting times for heart transplantation. We studied the relationship between heart transplant waiting time and transplant failure (removal from the waitlist, pretransplant death, or death or graft failure within 1 year) to determine the risk that conservative donor heart acceptance practices confer in terms of increasing the risk of failure among patients awaiting transplantation.

METHODS

We studied a cohort of 28,283 adults registered on the United Network for Organ Sharing heart transplant waiting list between 2000 and 2010. We used Kaplan-Meier methods with inverse probability censoring weights to examine the risk of transplant failure accumulated over time spent on the waiting list (pretransplant). In addition, we used transplant candidate blood type as an instrumental variable to assess the risk of transplant failure associated with increased wait time.

RESULTS

Our results show that those who wait longer for a transplant have greater odds of transplant failure. While on the waitlist, the greatest risk of failure is during the first 60 days. Doubling the amount of time on the waiting list was associated with a 10% (1.01, 1.20) increase in the odds of failure within 1 year after transplantation.

CONCLUSIONS

Our findings suggest a relationship between time spent on the waiting list and transplant failure, thereby supporting research aimed at defining adequate donor heart quality and acceptance standards for heart transplantation.

Impact of Socioeconomic Status on Patients Supported With a Left Ventricular Assist Device: An Analysis of the UNOS Database (United Network for Organ Sharing)

BACKGROUND

Low socioeconomic status (SES) is a known risk factor for heart failure, mortality among those with heart failure, and poor post heart transplant (HT) outcomes. This study sought to determine whether SES is associated with decreased waitlist survival while on left ventricular assist device (LVADs) support and after HT.

METHODS AND RESULTS

A total of 3361 adult patients bridged to primary HT with an LVAD between May 2004 and April 2014 were identified in the UNOS database (United Network for Organ Sharing). SES was measured using the Agency for Healthcare Research and Quality SES index using data from the 2014 American Community Survey. In the study cohort, SES did not have an association with the combined end point of death or delisting on LVAD support (P=0.30). In a cause-specific unadjusted model, those in the top (hazard ratio, 1.55; 95% confidence interval, 1.14-2.11; P=0.005) and second greatest SES quartile (hazard ratio 1.50; 95% confidence interval, 1.10-2.04; P=0.01) had an increased risk of death on device support compared with the lowest SES quartile. Adjusting for clinical risk factors mitigated the increased risk. There was no association between SES and complications. Post-HT survival, both crude and adjusted, was decreased for patients in the lowest quartile of SES index compared with all other SES quartiles.

CONCLUSIONS

Freedom from waitlist death or delisting was not affected by SES. Patients with a higher SES had an increased unadjusted risk of waitlist mortality during LVAD support, which was mitigated by adjusting for increased comorbid conditions. Low SES was associated with worse post-HT outcomes. Further study is needed to confirm and understand a differential effect of SES on post-transplant outcomes that was not seen during LVAD support before HT.

Mortality, rehospitalization, and post-transplant complications in gender-mismatched heart transplant recipients

BACKGROUND

Limited research has been published on outcomes in heart transplant (HT) recipients with gender-mismatched donors.

OBJECTIVE

Compare 3-year post-transplant outcomes in 2 groups of gender-mismatched HT recipients and a no-mismatch group.

METHODS

Sample: 347 HT recipients: 21.3% (74) received a heart from the opposite gender: Group 1: same gender donor/recipient (273, 78.7%); Group 2: female donor/male recipient (40, 11.5%); Group 3: male donor/female recipient (34, 9.8%).

OUTCOMES

mortality, hospitalization, and complications.

RESULTS

Female patients with male heart donors had shorter 3-year survival, were rehospitalized more days after HT discharge, and had more treated acute rejection episodes and cardiac allograft vasculopathy. No differences were found in: HT length of stay, respiratory failure, stroke, cancer, renal dysfunction, steroid-induced diabetes, number of IV-treated infections, or the timing of infection and rejection.

CONCLUSION

Female HT recipients with male donors had worse 3-year outcomes as compared to male-mismatch and no-mismatch groups.

Racial and ethnic disparities in outcomes after heart transplantation: A systematic review of contributing factors and future directions to close the outcomes gap

The demographics of patients undergoing heart transplantation in the United States have shifted over the last 10 years, with an increasing number of racial and ethnic minorities undergoing heart transplant. Multiple studies have shown that survival of African American patients after heart transplantation is lower compared with other ethnic groups. We review the data supporting the presence of this outcome disparity and examine the multiple mechanisms that contribute. With an increasingly diverse population in the United States, knowledge of these disparities, their mechanisms, and ways to improve outcomes is essential.

Racial Disparities in Outcomes of Adult Heart Transplantation

Background—

This study evaluated whether minority orthotopic heart transplant (OHT) recipients tend to be transplanted at worse performing centers.

Methods and Results—

OHT recipients between 2000 and 2010 were identified in the United Network for Organ Sharing database and stratified by race. Center performance was evaluated using observed-to-expected mortality ratios that were calculated using validated indexes for recipient and donor risk in OHT. The primary outcome was 1-year post-OHT mortality. A total of 102 centers performed OHT in 18 085 patients. Blacks had higher unadjusted 1-year mortality, which was confirmed after risk adjustment. Blacks had increased risk-adjusted mortality at poor performing centers (observed-to-expected mortality ratio, >1.2; odds ratio, 1.37 [95% confidence interval, 1.12–1.69]; P =0.002) and a strong trend toward increased mortality at excellent performing centers (observed-to-expected mortality ratio, <0.8; odds ratio, 1.42 [95% confidence interval, 0.99–2.02]; P =0.06). A higher proportion of blacks were treated at centers with higher-than-expected mortality (56.4% versus 47.1% whites versus 48.1% Hispanics; P <0.001), a finding that persisted after adjusting for insurance type and highest education level. In addition, there was a positive correlation between the percentage of blacks and observed-to-expected mortality ratios at the center level ( r =0.32; P =0.001). In multivariable analysis incorporating immunologic and socioeconomic variables, there was no clear dominant source for the disparities in outcomes of OHT between races.

Conclusions—

Blacks have a propensity to be transplanted at worse performing centers; however, center effect alone does not explain the mortality difference between ethnicities. Although referral of minorities to better performing centers would improve absolute survival, it would not likely eliminate the racial disparities that exist in OHT outcomes.

Gene expression profiling to study racial differences after heart transplantation

Background

The basis for increased mortality after heart transplantation in African Americans and other non-Caucasian racial groups is poorly defined. We hypothesized that increased risk of adverse events is driven by biological factors. To test this hypothesis in the IMAGE study, we determined whether the event rate of the primary outcome of acute rejection, graft dysfunction, death, or re-transplantation varied by race as a function of calcineurin inhibitor levels and gene expression profile (GEP) scores.

Methods

We determined the event rate of the primary outcome, comparing racial groups, stratified by time post-transplant. Logistic regression was used to compute the relative risk across racial groups and linear modeling was used to measure the dependence of CNI levels and GEP score on race.

Results

In 580 patients followed for a median of 19 months, the incidence of the primary endpoint in African Americans, other non-Caucasians, and Caucasians was 18.3%, 22.2%, and 8.5%, respectively (p<0.001). There were small but significant correlations of race and tacrolimus trough levels to GEP score. Tacrolimus levels were similar between races. Of patients receiving tacrolimus, other non-Caucasians had higher GEP scores than the other racial groups. African American recipients demonstrated a unique decrease in expression of the FLT3 gene in response to higher tacrolimus levels.

Conclusions

African Americans and other non-Caucasian heart transplant recipients were 2.5–3 times more likely than Caucasians to experience outcome events in IMAGE. The increased risk of adverse outcomes may be partly due to the biology of the alloimmune response, which is less effectively inhibited at similar tacrolimus levels in minority racial groups.

Cardiac transplantation in African Americans: a single-center experience

BACKGROUND

In view of limited data on the subject of graft and patient survival differences between African American (AA) and non-AA heart transplant recipients, we reviewed our experience.

HYPOTHESIS

There is a higher mortality among AA recipients compared with non-AA recipients after cardiac transplantation.

METHODS

The study included all AA patients who have received a heart transplant in our center since 1983. Stepwise Cox regression was used for covariates affecting the survival. The χ(2) test was employed to identify the effects of a mechanical assist device and pretransplant creatinine (Cr) on the outcomes in AA and non-AA patients. Kaplan-Meier curves were used to examine survival.

RESULTS

The average survival among AA recipients was 5.4 years, compared with 12 years for the non-AA recipients, with 1-, 5-, and 10-year survival rates of 80%, 55%, and 25%, respectively. This was found to be statistically inferior to the survival probabilities of 92%, 78%, and 58% for the non-AA group (P < 0.005). Based on stepwise Cox regression, the variables such as ethnicity (P < 0.05), pretransplant Cr (P < 0.05), presence of a mechanical assist device (P < 0.005), and United Network for Organ Sharing (UNOS) status at transplant (P < 0.05) independently predicted the outcomes. Kaplan-Meier analysis of pretransplant Cr level and survival showed that the AA group did significantly worse for all Cr classes.

CONCLUSIONS

There is a statistically significant difference in outcomes between AA and non-AA patients after cardiac transplantation. African American patients have decreased survival over a period of time. Pretransplant Cr, ethnicity, presence of a mechanical assist device, and UNOS status at transplantation are independent predictors of outcomes.