Racial and socioeconomic disparities in pediatric heart transplant outcomes in the era of anti-thymocyte globulin induction

Socioeconomic Status and Major Adverse Transplant Events in Pediatric Heart Transplant Recipients

Importance

Low socioeconomic status (SES) has been associated with higher risk of rejection and graft loss in pediatric heart transplant (HT) recipients. The association of SES with other posttransplant morbidities is unknown.

Objective

To assess whether low SES is associated with higher risk of a major adverse transplant event (MATE) among pediatric HT recipients.

Design, Setting, and Participants

Retrospective single-center cohort study at a children's hospital in Boston with consecutive primary HT recipients from 2006 to 2019 and follow-up through 2022. Data were analyzed from June 2023 to March 2024.

Exposure

Very low or low, moderate, and high or very high Childhood Opportunity Index (COI) for neighborhood (census tract) of patient residence.

Main Outcomes and Measures

Primary outcome was 3-year MATE-6 score assessed in 6-month survivors as cumulative burden of acute cellular rejection, antibody-mediated rejection, coronary vasculopathy, lymphoproliferative disease, kidney dysfunction, and infection, each as an ordinal score from 0 to 4 (24 for death or retransplant). Secondary outcomes were freedom from rejection during first 6 months, freedom from death or retransplant, MATE-3 score for events 1 to 3 (under immune suppression) and events 4 to 6 (chronic immune suppression effects), and each MATE component.

Results

Of 153 children analyzed, the median (IQR) age at HT was 7.2 (1.5-14.8) years, 99 (65%) were male, 16 (10%) were Black, 17 (11%) were Hispanic, and 106 (69%) were White. Fifty patients (33%) lived in very low or low, 17 (11%) in moderate, and 86 (56%) in high or very high COI neighborhoods. There was no significant group difference in mean (SD) 3-year MATE-6 score (very low or low COI, 3.4 [6.5]; moderate COI, 2.4 [6.3]; and high or very high COI, 4.0 [6.9]). Furthermore, there was no group difference in mean (SD) MATE-3 scores for underimmune suppression (very low or low COI, 1.9 [3.5]; moderate COI, 1.2 [3.2]; and high or very high COI, 2.2 [3.6]), chronic immune suppression effects (very low or low COI, 1.6 [3.3]; moderate COI, 1.1 [3.2]; and high or very high COI, 1.8 [3.6]), individual MATE components, rejection during the first 6 months, or death or retransplant.

Conclusions and relevance

In this cohort study of pediatric HT recipients, there was no difference in posttransplant outcomes among recipients stratified by SES, a notable improvement from prior studies. These findings may be explained by state-level health reform, standardized posttransplant care, and early awareness of outcome disparities.

Lower opportunity ZIP code is associated with worse outcomes after listing in pediatric heart transplantation

BACKGROUND

The Child Opportunity Index (COI) comprehensively measures children's social determinants of health. We describe association between COI and outcomes after listing for heart transplantation.

METHODS

We conducted a retrospective review of the United Network for Organ Sharing (UNOS) database for U.S. children listed for heart transplant between 2012 and 2020. ZIP codes were utilized to assign COI. Primary outcome was survival from time of listing. Secondary outcomes included waitlist survival, 1-year post-transplant survival, and conditional 1-year post-transplant survival. Cox regression was performed adjusting for payor, age, race, diagnosis, and support at listing for all outcomes except waitlist survival, for which Fine-Gray competing risk analysis was performed.

RESULTS

Of 5,723 children listed, 109 were excluded due to missing ZIP codes. Race/ethnicity and payor were associated with COI (p < 0.001). Patients living in very low COI ZIP codes compared to all others had increased mortality from time of listing (HR 1.16, CI 1.03-1.32, p = 0.02) with 1-, 5-, and 9-year survival of 79.3% vs 82.2%, 66.5% vs 73.0%, and 53.6% vs 64.7% respectively, were more likely to be removed from the waitlist due to death or being too sick (subdistribution HR 1.26, 95% CI 1.10-1.42), and had increased mortality conditional on one-year post-transplant survival (HR 1.38, 1.09-1.74, p = 0.008) with 1-, 3-, and 5- year survival of 94.7% vs 97.3%, 87.0% vs 93.1%, and 78.6% vs 86.9%.

CONCLUSIONS

Children living in lower opportunity ZIP codes had poorer survival from time of listing, poorer waitlist survival, and poorer conditional one-year post-transplant survival.

Assessing the Impact of Neighborhood and Built Environment on Pediatric Perioperative Care: A Systematic Review of the Literature

CONTEXT

Neighborhood and built environment encompass one key area of the Social Determinants of Health (SDOH) and is frequently assessed using area-level indices.

OBJECTIVE

We sought to systematically review the pediatric surgery literature for use of commonly applied area-level indices and to compare their utility for prediction of outcomes.

DATA SOURCES

A literature search was conducted using PubMed, Ovid MEDLINE, Ovid MEDLINE Epub Ahead of Print, PsycInfo, and an artificial intelligence search tool (1/2013-2/2023).

STUDY SELECTION

Inclusion required pediatric surgical patients in the US, surgical intervention performed, and use of an area-level metric.

DATA EXTRACTION

Extraction domains included study, patient, and procedure characteristics.

RESULTS

Area Deprivation Index is the most consistent and commonly accepted index. It is also the most granular, as it uses Census Block Groups. Child Opportunity Index is less granular (Census Tract), but incorporates pediatric-specific predictors of risk. Results with Social Vulnerability Index, Neighborhood Deprivation Index, and Neighborhood Socioeconomic Status were less consistent.

LIMITATIONS

All studies were retrospective and quality varied from good to fair.

CONCLUSIONS

While each index has strengths and limitations, standardization on ideal metric(s) for the pediatric surgical population will help build the inferential power needed to move from understanding the role of SDOH to building meaningful interventions towards equity in care.

TYPE OF STUDY

Systematic Review.

LEVEL OF EVIDENCE

Level III.

DQB1 antigen matching improves rejection-free survival in pediatric heart transplant recipients

BACKGROUND

Presence of donor-specific antibodies (DSAs), particularly to class II antigens, remains a major challenge in pediatric heart transplantation. Donor-recipient human leukocyte antigen (HLA) matching is a potential strategy to mitigate poor outcomes associated with DSAs. We evaluated the hypothesis that antigen mismatching at the DQB1 locus is associated with worse rejection-free survival.

METHODS

Data were collected from Scientific Registry of Transplant Recipients for all pediatric heart transplant recipients 2010-2021. Only transplants with complete HLA typing at the DQB1 locus for recipient and donor were included. Primary outcome was rejection-free graft survival through 5 years.

RESULTS

Of 5,115 children, 4,135 had complete DQB1 typing and were included. Of those, 503 (12%) had 0 DQB1 donor-recipient mismatches, 2,203 (53%) had 1, and 1,429 (35%) had 2. Rejection-free survival through 5 years trended higher for children with 0 DQB1 mismatches (68%), compared to those with 1 (62%) or 2 (63%) mismatches (pairwise p = 0.08 for both). In multivariable analysis, 0 DQB1 mismatches remained significantly associated with improved rejection-free graft survival compared to 2 mismatches, while 1 DQB1 mismatch was not. Subgroup analysis showed the strongest effect in non-Hispanic Black children and those undergoing retransplant.

CONCLUSIONS

Matching at the DQB1 locus is associated with improved rejection-free survival after pediatric heart transplant, particularly in Black children, and those undergoing retransplant. Assessing high-resolution donor typing at the time of allocation may further corroborate and refine this association. DQB1 matching may improve long-term outcomes in children stabilized either with optimal pharmacotherapy or supported with durable devices able to await ideal donors.

Review on clinician bias and its impact on racial and socioeconomic disparities in pediatric heart transplantation

This expert review seeks to highlight implicit bias in health care, transplant medicine, and pediatric heart transplantation to focus attention on the role these biases may play in the racial/ethnic and socioeconomic disparities noted in pediatric heart transplantation. This review breaks down the transplant decision making process to highlight points at which implicit bias may affect outcomes and discuss how the science of human decision making may help understand these complex processes.

Changes in estimated glomerular filtration rate over the first year following repeat heart transplant in children and young adults

BACKGROUND

Renal function is reduced in patients undergoing heart transplant due to hemodynamic compromise, cardiorenal syndrome, and nephrotoxin exposure. No current studies evaluate renal function in retransplants.

METHODS

We reviewed all heart transplants at our center from 1995 to 2021 and matched first-time heart transplants with retransplants, based on age at transplant, sex, and race. Estimated glomerular filtration rate (eGFR) was derived from CKiD-U25 calculator using creatinine and measured prior to transplant, 1-week post-transplant, 1-3, 6, and 12 months post-transplant, and recent follow-up. Changes in eGFR were measured within and between patients using a piecewise linear mixed effect model with matching. Exploratory univariate analysis was performed to evaluate pre-transplant risk factors for decreased eGFR.

RESULTS

The unmatched cohort included 393 heart transplant recipients, with 47 being retransplants. Thirty-eight patients in both groups with at least 1 year of follow-up underwent matching. Both retransplants and first-time transplants had an initial decline in eGFR. eGFR rebounded to baseline or above baseline at 1-3 months post-transplant, but eGFR in retransplants remained significantly lower. At 1-year post-transplant, the average eGFR was 67.8 ± 4.3 mL/min/1.73 m2 versus 104.7 ± 4.3 mL/min/1.73 m2 (p < .001) in the retransplants and first-time transplants group, respectively.

CONCLUSION

This study provides data on anticipated renal trajectory following retransplantation.

Pediatric donor heart acceptance practices in the United States: What is really being considered?

BACKGROUND

Recent studies demonstrate high offer decline and organ non-utilization rates are associated with increased pediatric heart transplant waitlist mortality. We sought to determine which donor, candidate, and offer specific variables most importantly influenced these decisions using only data available at the time of each offer.

METHODS

Retrospective review of pediatric (<18 years) heart donor offers made to pediatric candidates in the United States between 2010 and 2020. In addition to standard donor, candidate, and offer data available in UNOS, we extracted objective and qualitative valvar and myocardial function data from all available donor echocardiogram reports.

RESULTS

During the study period, 5625 pediatric donor hearts produced 30 156 offers to 4905 unique candidates, of which 88.7% of all offers were declined and 39.2% of organs were not utilized by pediatric waitlisted candidates. Of the 60.8% utilized hearts, 89.7% had a 'cumulatively' normal echocardiogram at the time of offer acceptance; 62.9% of hearts not utilized for a pediatric candidate also had a cumulatively normal final echocardiogram. Random forest and logistic regression modeling demonstrated good predictive performance (AUROC ≥0.83) of likelihood to accept when utilizing donor, candidate, and offer specific variables. SHAP variable importance scores demonstrated number of prior offer declines and candidate institution's prior year acceptance rates as the two most important variables influencing offer decisions.

CONCLUSIONS

Behavioral economics appear to play a significant role in pediatric heart transplant candidate institutions' acceptance practices, even when considering the arguably healthier pediatric donor population. Removal of prior institution's decisions from DonorNet may help increase donor utilization.

Neighborhood Childhood Opportunity, Race/Ethnicity, and Surgical Outcomes in Children With Congenital Heart Disease

BACKGROUND

Racial and ethnic disparities in outcomes for children with congenital heart disease (CHD) coexist with disparities in educational, environmental, and economic opportunity.

OBJECTIVES

We sought to determine the associations between childhood opportunity, race/ethnicity, and pediatric CHD surgery outcomes.

METHODS

Pediatric Health Information System encounters aged <18 years from 2016 to 2022 with International Classification of Diseases-10th edition codes for CHD and cardiac surgery were linked to ZIP code-level Childhood Opportunity Index (COI), a score of neighborhood educational, environmental, and socioeconomic conditions. The associations of race/ethnicity and COI with in-hospital surgical death were modeled with generalized estimating equations and formal mediation analysis. Neonatal survival after discharge was modeled by Cox proportional hazards.

RESULTS

Of 54,666 encounters at 47 centers, non-Hispanic Black (Black) (OR: 1.20; P = 0.01), Asian (OR: 1.75; P < 0.001), and Other (OR: 1.50; P < 0.001) groups had increased adjusted mortality vs non-Hispanic Whites. The lowest COI quintile had increased in-hospital mortality in unadjusted and partially adjusted models (OR: 1.29; P = 0.004), but not fully adjusted models (OR: 1.14; P = 0.13). COI partially mediated the effect of race/ethnicity on in-hospital mortality between 2.6% (P = 0.64) and 16.8% (P = 0.029), depending on model specification. In neonatal multivariable survival analysis (n = 13,987; median follow-up: 0.70 years), the lowest COI quintile had poorer survival (HR: 1.21; P = 0.04).

CONCLUSIONS

Children in the lowest COI quintile are at risk for poor outcomes after CHD surgery. Disproportionally increased mortality in Black, Asian, and Other populations may be partially mediated by COI. Targeted investment in low COI neighborhoods may improve outcomes after hospital discharge. Identification of unmeasured factors to explain persistent risk attributed to race/ethnicity is an important area of future exploration.

The Year in Review: Anesthesia for Congenital Heart Disease 2022

This review focuses on the literature published during the calendar year 2022 that is of interest to anesthesiologists taking care of children and adults with congenital heart disease (CHD). Four major themes are discussed: enhanced recovery after surgery(ERAS); diversity, equity, and inclusion; the state of pediatric cardiac anesthesiology as a subspecialty in the United States; and neuromonitoring for pediatric cardiac surgery.

Addressing pediatric surgical health inequities through quality improvement efforts

Concepts of healthcare quality and health equity should be inextricably linked but are often pursued separately. Quality improvement (QI) can serve as a powerful means to eliminate health inequities by adopting an equity-focused lens to diagnose and address baseline disparities among pediatric populations using targeted interventions. QI and pediatric surgery practitioners should integrate concepts of equity at every stage of formulating a QI project including conceptualization, planning, and execution. Early adaptation of an equity conscious perspective using QI methodology can prevent exacerbation of preexisting disparities while improving overall outcomes.

Elective and non-elective endomyocardial biopsy in heart transplant patients and procedural outcomes: An IMPACT registry analysis

BACKGROUND

Endomyocardial biopsies are standard of care for transplant surveillance, however the procedural risks are not well established, especially in children. The purpose of the study was therefore to assess procedural risks and outcomes associated with elective (surveillance) biopsies and non-elective (clinically indicated) biopsies.

METHODS

We used the NCDR IMPACT registry database for this retrospective analysis. Patients undergoing an endomyocardial biopsy were identified using the procedural code, with a diagnosis of heart transplantation required. Data regarding indication, hemodynamics, adverse events and outcomes was gathered and analyzed.

RESULTS

A total of 32 547 endomyocardial biopsies were performed between 2012-2020; 31 298 (96.5%) elective and 1133 (3.5%) were non-elective biopsies. Non-elective biopsy was more commonly performed in infants and in those above 18 years of age, in female and in Black race patients and in those with non-private insurance (all p < .05) and showed hemodynamic derangements. Overall rate of complications was low. Combined major adverse events were more common in non-elective patients, with sicker patient profile, use of general anesthesia and femoral access with overall decline in these events over time.

CONCLUSIONS

This large-scale analysis shows safety of surveillance biopsies and that non-elective biopsies carry a small but significant risk of major adverse event. Patient profile impacts the safety of the procedure. These data may serve as important comparison point for newer non-invasive tests and for bench marking, especially in children.