Lower socioeconomic status is associated with worse outcomes after both listing and transplanting children with heart failure

Hospital volume does not mitigate the impact of area socioeconomic deprivation on heart transplantation outcomes

BACKGROUND

While structural socioeconomic inequity has been linked with inferior health outcomes, some have postulated reduced access to high-quality care to be the mediator. We assessed whether treatment at high-volume centers (HVC) would mitigate the adverse impact of area deprivation on heart transplantation (HT) outcomes.

METHODS

All HT recipients ≥18 years were identified in the 2005-2022 Organ Procurement and Transplantation Network. Neighborhood socioeconomic deprivation was assessed using the previously validated Area Deprivation Index. Recipients with scores in the highest quintile were considered Most Deprived (others: Less Deprived). Hospitals in the highest quartile by cumulative center volume (≥21 transplants/year) were classified as HVC. The primary outcome was post-transplant survival.

RESULTS

Of 38,022 HT recipients, 7,579 (20%) were considered Most Deprived. Following risk adjustment, Most Deprived demonstrated inferior survival at 3 (hazard ratio [HR] 1.14, 95% confidence interval [CI] 1.06-1.21) and 5 years following transplantation (HR 1.13, CI 1.07-1.20). Similarly, Most Deprived faced greater graft failure at 3 (HR 1.14, CI 1.06-1.22) and 5 years (HR 1.13, CI 1.07-1.20). Evaluating patients transplanted at HVC, Most Deprived continued to face greater mortality at 3 (HR 1.10, CI 1.01-1.21) and 5 years (HR 1.10, CI 1.01-1.19). The interaction between Most Deprived status and care at HVC was not significant, such that transplantation at HVC did not ameliorate the survival disparity between Most and Less Deprived.

CONCLUSIONS

Area socioeconomic disadvantage is independently associated with inferior survival. Transplantation at HVC did not eliminate this inequity. Future efforts are needed to increase engagement with longitudinal follow-up care and address systemic root causes to improve outcomes.

International Society for Heart and Lung Transplantation Guidelines for the Evaluation and Care of Cardiac Transplant Candidates-2024

The "International Society for Heart and Lung Transplantation Guidelines for the Evaluation and Care of Cardiac Transplant Candidates-2024" updates and replaces the "Listing Criteria for Heart Transplantation: International Society for Heart and Lung Transplantation Guidelines for the Care of Cardiac Transplant Candidates-2006" and the "2016 International Society for Heart Lung Transplantation Listing Criteria for Heart Transplantation: A 10-year Update." The document aims to provide tools to help integrate the numerous variables involved in evaluating patients for transplantation, emphasizing updating the collaborative treatment while waiting for a transplant. There have been significant practice-changing developments in the care of heart transplant recipients since the publication of the International Society for Heart and Lung Transplantation (ISHLT) guidelines in 2006 and the 10-year update in 2016. The changes pertain to 3 aspects of heart transplantation: (1) patient selection criteria, (2) care of selected patient populations, and (3) durable mechanical support. To address these issues, 3 task forces were assembled. Each task force was cochaired by a pediatric heart transplant physician with the specific mandate to highlight issues unique to the pediatric heart transplant population and ensure their adequate representation. This guideline was harmonized with other ISHLT guidelines published through November 2023. The 2024 ISHLT guidelines for the evaluation and care of cardiac transplant candidates provide recommendations based on contemporary scientific evidence and patient management flow diagrams. The American College of Cardiology and American Heart Association modular knowledge chunk format has been implemented, allowing guideline information to be grouped into discrete packages (or modules) of information on a disease-specific topic or management issue. Aiming to improve the quality of care for heart transplant candidates, the recommendations present an evidence-based approach.

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.

Social Determinants of Health and Outcomes After Pediatric Ventricular Assist Device Implantation

BACKGROUND

Limited research exists on the influence of social determinants of health (SDOH) on outcomes in pediatric patients with advanced heart failure receiving mechanical circulatory support.

METHODS

Linkage of the Pediatric Interagency Registry for Mechanical Circulatory Support (Pedimacs) and Society of Thoracic Surgeon's Congenital Heart Surgery Database (STS-CHSD) identified pediatric patients who underwent ventricular assist device (VAD) implantation from 2012 to 2022 with available residential zip codes. Utilizing the available zip codes, each patient was assigned a Childhood Opportunity Index (COI) score. Level of childhood opportunity, race, and insurance type were used as proxies for SDOH. Major outcomes included death, transplant, alive with device, and recovery. Secondary outcomes were adverse events. Statistical analyses were performed using the Kaplan-Meier survival, competing risk analyses, and multivariable Cox proportional hazards model.

RESULTS

Three hundred seventeen patients were included in the study. Childhood opportunity level and insurance status did not significantly impact morbidity or mortality after VAD implantation. White race was associated with reduced 1-year survival (71% in White vs. 87% in non-White patients, p = 0.05) and increased risk of pump thrombosis (p = 0.02).

CONCLUSION

Childhood opportunity level and insurance status were not linked to morbidity and mortality in pediatric patients after VAD implantation. Notably, White race was associated with higher mortality rates. The study underscores the importance of considering SDOH in evaluating advanced therapies for pediatric heart failure and emphasizes the need for accurate socioeconomic data collection in future studies and national registries.

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.

Impact of Community Socioeconomic Distress on Survival Following Heart Transplantation

OBJECTIVE

The aim of this study was to assess the impact of community-level socioeconomic deprivation on survival outcomes following heart transplantation.

BACKGROUND

Despite growing awareness of socioeconomic disparities in the US health care system, significant inequities in outcomes remain. While recent literature has increasingly considered the effects of structural socioeconomic deprivation, the impact of community socioeconomic distress on outcomes following heart transplantation has not yet been elucidated.

METHODS

All adult heart transplant recipients from 2004 to 2022 were ascertained from the Organ Procurement and Transplantation Network. Community socioeconomic distress was assessed using the previously validated Distressed Communities Index, a metric that represents education level, housing vacancies, unemployment, poverty rate, median household income, and business growth by zip code. Communities in the highest quintile were considered the Distressed cohort (others: Non-Distressed ). Outcomes were considered across 2 eras (2004-2018 and 2019-2022) to account for the 2018 UNOS Policy Change. Three- and 5-year patient and graft survival were assessed using Kaplan-Meier and Cox proportional hazards models.

RESULTS

Of 36,777 heart transplants, 7450 (20%) were considered distressed . Following adjustment, distressed recipients demonstrated a greater hazard of 5-year mortality from 2004 to 2018 [hazard ratio (HR)=1.10, 95% confidence interval (CI): 1.03-1.18; P =0.005] and 3-year mortality from 2019 to 2022 (HR=1.29, 95% CI: 1.10-1.51; P =0.002), relative to nondistressed . Similarly, the distressed group was associated with increased hazard of graft failure at 5 years from 2004 to 2018 (HR=1.10, 95% CI: 1.03-1.18; P =0.003) and at 3 years from 2019 to 2022 (HR=1.31, 95% CI: 1.11-1.53; P =0.001).

CONCLUSIONS

Community-level socioeconomic deprivation is linked with inferior patient and graft survival following heart transplantation. Future interventions are needed to address pervasive socioeconomic inequities in transplantation outcomes.

The effect of socioeconomic status on pediatric heart transplant outcomes at a single institution between 2013 and 2022

BACKGROUND

Disparities in pediatric heart transplant outcomes based on socioeconomic status (SES) have been previously observed. However, there is a need to reevaluate these associations in contemporary settings with advancements in transplant therapies and increased awareness of health disparities. This retrospective study aims to investigate the relationship between SES and outcomes for pediatric heart transplant patients.

METHODS

Data were collected through a chart review of 176 pediatric patients who underwent first orthotopic heart transplantation (OHT) at a single center from 2013 to 2021. The Area Deprivation Index (ADI), a composite score based on U.S. census data, was used to quantify SES. Cox proportional hazards models and generalized linear models were employed to analyze the association between SES and graft failure, rejection rates, and hospitalization rates.

RESULTS

The analysis revealed no statistically significant differences in graft failure rates, rejection rates, or hospitalization rates between low-SES and high-SES pediatric heart transplant patients for our single-center study.

CONCLUSION

There may be patient education, policies, and social resources that can help mitigate SES-based healthcare disparities. Additional multi-center research is needed to identify post-transplant care that promotes patient equity.

Demographic Factors, Medication Adherence, and Post-transplant Health Outcomes: A Longitudinal Multilevel Modeling Approach

Few studies in pediatric solid organ transplantation have examined non-adherence to immunosuppressive medication over time and its associations with demographic factors and post-transplant outcomes including late acute rejection and hospitalizations. We examined longitudinal variation in patient Medication Level Variability Index (MLVI) adherence data from pediatric kidney, liver, and heart transplant recipients. Patient and administrative data from the United Network for Organ Sharing were linked with electronic health records and MLVI values for 332 patients. Multilevel mediation modeling indicated comparatively more variation in MLVI values between patients than within patients, longitudinally, over 10 years post transplant. MLVI values significantly predicted late acute rejection and hospitalization. MLVI partially mediated patient factors and post-transplant outcomes for patient age indicating adolescents may benefit most from intervention efforts. Results demonstrate the importance of longitudinal assessment of adherence and differences among patients. Efforts to promote medication adherence should be adapted to high-risk patients to increase likelihood of adherence.

Individual-Level Socioeconomic Position and Long-Term Prognosis in Danish Heart-Transplant Recipients

Socioeconomic deprivation can limit access to healthcare. Important gaps persist in the understanding of how individual indicators of socioeconomic disadvantage may affect clinical outcomes after heart transplantation. We sought to examine the impact of individual-level socioeconomic position (SEP) on prognosis of heart-transplant recipients. A population-based study including all Danish first-time heart-transplant recipients (n = 649) was conducted. Data were linked across complete national health registers. Associations were evaluated between SEP and all-cause mortality and first-time major adverse cardiovascular event (MACE) during follow-up periods. The half-time survival was 15.6 years (20-year period). In total, 330 (51%) of recipients experienced a first-time cardiovascular event and the most frequent was graft failure (42%). Both acute myocardial infarction and cardiac arrest occurred in ≤5 of recipients. Low educational level was associated with increased all-cause mortality 10-20 years post-transplant (adjusted hazard ratio [HR] 1.95, 95% confidence interval [CI] 1.19-3.19). During 1-10 years post-transplant, low educational level (adjusted HR 1.66, 95% CI 1.14-2.43) and low income (adjusted HR 1.81, 95% CI 1.02-3.22) were associated with a first-time MACE. In a country with free access to multidisciplinary team management, low levels of education and income were associated with a poorer prognosis after heart transplantation.

Equity factors in pediatric transplant listing: Initial findings from a single center review

BACKGROUND

In order to improve transparency within the patient selection process, a transplant listing advisory committee was formed within the Boston Children's Hospital Pediatric Transplant Center. Its mission is to promote equity in access to organ transplantation by ensuring that the institutional transplant selection criteria are fair, unbiased, and nondiscriminatory. The committee conducts comprehensive case and data review of individual characteristics and reviews in aggregate to identify potential systems bias.

METHODS

Charts for 256 patients evaluated for transplant from 3/2016 to 3/2019 were reviewed. Among these, 64 (25%) patients were declined for transplant. Univariate logistic regression analysis was used to identify demographic variables and vulnerable status factors associated with being declined. Odds ratios (OR) are reported.

RESULTS

Among all patients, median age was 8.5 years and 58% were male. Asian patients were more likely to be declined than White patients (OR = 5.3, Wald p = .007). Socioeconomic factors that affected likelihood of listing decline included concerns for caregivers' ability to manage and understand care requirements (OR = 3.8, p = .011), caregiver employment status (OR = 1.9, p = .042), and use of public assistance programs (OR = 2.2, p = .05). Patients with severe neurodevelopmental delay were more likely to be declined for listing (OR = 3.7, p = .019).

CONCLUSION

This analysis identified areas of potential bias related to race, socioeconomic status, and neurodevelopmental delay where initiatives can be targeted. Advisory committees are an important aspect of evaluating equity in transplant center selection policy and practice.

Trends in Contemporary Use of Ventricular Assist Devices in Children Awaiting Heart Transplantation and Their Outcomes by Race/Ethnicity

This retrospective study included children aged ≤18 years who had durable ventricular assist devices (VADs) as a bridge to transplantation from the United Network Organ Sharing (UNOS) database between 2011 and 2020. We evaluated 90 day waitlist mortality and 1 year posttransplant mortality after VAD implantation in children stratified by race/ethnicity: Black, White, and Others. The VAD was used in a higher proportion of Black children listed for heart transplantation (HT) (26%) versus Other (25%) versus White (22%); p < 0.01. Black children had Medicaid health insurance coverage (67%) predominantly at the time of listing for HT. There was no significant overall difference in waitlist survival among the three groups supported with VAD at the time of listing (log-rank p = 0.4). On the other hand, the 90 day waitlist mortality after the VAD implantation at listing and while listed was the lowest among Black (6%) compared with White (13%) and Other (14%) ( p < 0.01). The multivariate regression analysis showed that Other race (hazard ratio [HR], 2.29; p < 0.01), Black race (HR, 2.13; p < 0.01), use of mechanical ventilation (HR, 1.72; p = 0.01), and Medicaid insurance (HR, 1.54; p = 0.04) were independently associated with increased 1 year posttransplant mortality. In conclusion, Black children had more access to durable VAD support than White children. The 90 day waitlist mortality was significantly lower in Black children compared with White and Other after VAD implantation. However, Black and Other racial/ethnic children with VAD at transplant had higher 1 year posttransplant mortality than White children. Future studies to elucidate the reasons for these disparities are needed.

A systematic review of social determinants of health in pediatric organ transplant outcomes

BACKGROUND

Equitable access to pediatric organ transplantation is critical, although risk factors negatively impacting pre- and post-transplant outcomes remain. No synthesis of the literature on SDoH within the pediatric organ transplant population has been conducted; thus, the current systematic review summarizes findings to date assessing SDoH in the evaluation, listing, and post-transplant periods.

METHODS

Literature searches were conducted in Web of Science, Embase, PubMed, and Cumulative Index to Nursing and Allied Health Literature databases.

RESULTS

Ninety-three studies were included based on pre-established criteria and were reviewed for main findings and study quality. Findings consistently demonstrated disparities in key transplant outcomes based on racial or ethnic identity, including timing and likelihood of transplant, and rates of rejection, graft failure, and mortality. Although less frequently assessed, variations in outcomes based on geography were also noted, while findings related to insurance or SES were inconsistent.

CONCLUSION

This review underscores the persistence of SDoH and disparity in equitable transplant outcomes and discusses the importance of individual and systems-level change to reduce such disparities.

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

BACKGROUND

Black race is associated with worse outcomes across solid organ transplantation. Augmenting immunosuppression through antithymocyte globulin (ATG) induction may mitigate organ rejection and graft loss. We investigated whether racial and socioeconomic outcome disparities persist in children receiving ATG induction.

METHODS

Using the Pediatric Heart Transplant Society registry, we compared outcomes in Black and White children who underwent heart transplant with ATG induction between 2000 and 2020. The primary outcomes of treated rejection, rejection with hemodynamic compromise (HC), and graft loss (death or re-transplant). We explored the association of these outcomes with race and socioeconomic disparity, assessed using a neighborhood deprivation index [NDI] score at 1-year post-transplant (high NDI score implies more socioeconomic disadvantage).

RESULTS

The study cohort included 1,719 ATG-induced pediatric heart transplant recipients (22% Black, 78% White). There was no difference in first year treated rejection (Black 24.5%, White 28.1%, p = 0.2). During 10 year follow up, the risk of treated rejection was similar; however, Black recipients were at higher risk of HC rejection (p = 0.009) and graft loss (p = 0.02). Black recipients had a higher mean NDI score (p < 0.001). Graft loss conditional on 1-year survival was associated with high NDI score in both White and Black recipients (p < 0.0001). In a multivariable Cox model, both high NDI score (HR 1.97, 95% CI 1.23-3.17) and Black race (HR 2.22, 95% CI 1.40-3.53) were associated with graft loss.

CONCLUSION

Black race and socioeconomic disadvantage remain associated with late HC rejection and graft loss in children with ATG induction. These disparities represent important opportunities to improve long term transplant outcomes.

Worsening racial disparity in waitlist mortality for pediatric heart transplant candidates since the 2016 Pediatric Heart Allocation Policy revision

BACKGROUND

The US Pediatric Heart Allocation Policy (PHAP) was revised in March 2016, with the goal of reducing waitlist mortality. We evaluated the hypothesis that these changes, which increased status exceptions, have worsened racial disparities in waitlist outcomes.

METHODS

Children in the Pediatric Heart Transplant Study database listed for first heart transplant from January 2012 - June 2020 were included and stratified by listing before (Era 1) or after (Era 2) the PHAP revision.

RESULTS

A total of 4,089 children were listed during the study period. Compared with white children (n = 2648), non-white children (n = 1441) were more likely to have an underlying diagnosis of cardiomyopathy in both eras. Waitlist mortality was similar in white and non-white children in Era 1, but comparatively worse for non-white children in Era 2. In multivariable analysis controlling for diagnosis, age, and severity markers, non-white children had a significantly higher waitlist mortality only in Era 2 (Era 1: sHR 1.22 [95%CI 0.90 - 1.66] vs. Era 2: sHR 1.57 [95%CI 1.17 - 2.10]).

CONCLUSIONS

Widening racial disparities in waitlist mortality may be an unintended consequence of the 2016 PHAP revision. Additional analyses may inform the degree to which this policy vs. unrelated changes in care differentially contribute to these disparities.

Social Inequalities in Non-ischemic Cardiomyopathies

Heart failure (HF) has various characteristics, such as etiology, clinical course, and clinical characteristics. Several studies reported the clinical findings of the characteristics of non-ischemic cardiomyopathy. There have been issues with genetic, biochemical, or pathophysiological problems. Some studies have been conducted on non-ischemic cardiomyopathy and social factors, for instance, racial disparities in peripartum cardiomyopathy (PPCM) or the social setting of hypertrophic cardiomyopathy. However, there have been insufficient materials to consider the relationship between social factors and clinical course in non-ischemic cardiomyopathies. There were various methodologies in therapeutic interventions, such as pharmacological, surgical, or rehabilitational, and educational issues. However, interventions that could be closely associated with social inequality have not been sufficiently elucidated. We will summarize the effects of social equality, which could have a large impact on the development and progression of HF in non-ischemic cardiomyopathies.

Association of Race With Postoperative Mortality Following Major Abdominopelvic Trauma in Children

BACKGROUND

The leading cause of mortality among children is trauma. Race and ethnicity are critical determinants of pediatric postsurgical outcomes, with minority children generally experiencing higher rates of postoperative morbidity and mortality than White children. This pattern of poorer outcomes for racial and/or ethnic minority children has also been demonstrated in children with head and limb traumas. While injuries to the abdomen and pelvis are not as common, they can be life-threatening. Racial and/or ethnic differences in outcomes of pediatric abdominopelvic operative traumas have not been examined. Our objective was to determine whether disparities exist in postoperative mortality among children with major abdominopelvic trauma.

MATERIALS AND METHODS

We performed a retrospective analysis of the Healthcare Cost and Utilization Project Kids' Inpatient Database for 2003, 2006, 2009, and 2012. Patients were included if they were < 18 years, sustained a major abdominopelvic injury, and underwent subsequent surgical intervention. Our primary outcome was inpatient mortality, comparing children of different race and/or ethnicity.

RESULTS

We identified a weighted cohort of 13,955 children, of whom 6765 (48.5%) were White, 3614 (25.9%) Black, and 2647 (19.0%) Hispanic. After adjusting for covariates, Black children were 94% more likely to die than their White peers (3.3% versus 1.6%, adjusted-RR:1.94, 95%CI: 1.33-2.82, P = 0.001). Hispanic children (adjusted-RR:1.99, 95%CI: 1.36-2.91, P < 0.001) and those of other race and/or ethnicity (adjusted-RR: 2.02, 95%CI:1.20-3.40, P = 0.008) were also more likely to die compared to their White peers.

CONCLUSIONS

Black and Hispanic children who require operative intervention following major abdominopelvic trauma have a higher risk of postoperative mortality compared with White children.

An ethical analysis of obesity as a determinant of pediatric heart transplant candidacy

BACKGROUND

Inclusion of BMI as criterion in the determination of heart transplant candidacy in children is a clinical and ethical challenge. Childhood obesity is increasing and children with heart disease are not spared. Currently, many adult heart transplant centers consider class II obesity and higher (BMI > 35 kg/m² ) to be a relative contraindication for transplantation due to risk of poor outcome after transplant. No national guidelines exist regarding consideration of BMI in pediatric heart transplant and outcomes data are limited. This leaves decisions about transplant candidacy in obese pediatric patients to individual institutions or on a case-by-case basis, allowing for bias and inequity.

METHODS

We review (a) the prevalence of childhood obesity, including among heart transplant candidates, (b) the lack of existing BMI guidelines, and (c) relevant literature on BMI and pediatric heart transplant outcomes. We discuss the ethical considerations of using obesity as a criterion using the principles of utility, justice, and respect for persons.

RESULTS

Existing transplant outcomes data do not show that obese children have different or poor enough outcomes compared to non-obese children to warrant exclusion. Moreover, obesity in the United States is unequally distributed by race and socioeconomic status. Children already suffering from health disparities are therefore doubly penalized if obesity denies them access to life-saving transplant.

CONCLUSION

Insufficient data exist to support using any BMI cutoff as an absolute contraindication for heart transplant in children. Attention should be paid to health equity issues when considering excluding a patient for transplant based on obesity.

Socioeconomic Status and Long-term Outcomes in Single Ventricle Heart Disease

BACKGROUND

Low socioeconomic status (SES) has emerged as an important risk factor for higher short-term mortality and neurodevelopmental outcomes in children with hypoplastic left heart syndrome and related anomalies; yet little is known about how SES affects these outcomes over the long-term.

METHODS

We linked data from the Single Ventricle Reconstruction trial to US Census Bureau data to analyze the relationship of neighborhood SES tertiles with mortality and transplantation, neurodevelopment, quality of life, and functional status at 5 and 6 years post-Norwood procedure (N = 525). Cox proportional hazards regression and linear regression were used to assess the association of SES with mortality and neurodevelopmental outcomes, respectively.

RESULTS

Patients in the lowest SES tertile were more likely to be racial minorities, older at stage 2 and Fontan procedures, and to have more complications and fewer cardiac catheterizations over follow-up (all P < .05) compared with patients in higher SES tertiles. Unadjusted mortality was highest for patients in the lowest SES tertile and lowest in the highest tertile (41% vs 29%, respectively; log-rank P = .027). Adjustment for patient birth and Norwood factors attenuated these differences slightly (P = .055). Patients in the lowest SES tertile reported lower functional status and lower fine motor, problem-solving, adaptive behavior, and communication skills at 6 years (all P < .05). These differences persisted after adjustment for baseline and post-Norwood factors. Quality of life did not differ by SES.

CONCLUSIONS

Among patients with hypoplastic left heart syndrome, those with low SES have worse neurodevelopmental and functional status outcomes at 6 years. These differences were not explained by other patient or clinical characteristics.

Variations in Criteria and Practices for Heart Transplantation Listing Among Pediatric Transplant Cardiologists

Ethical issues in pediatric heart transplantation (Htx) include resource allocation, benefit, and burden assessment in high-risk recipients, and informed consent. Practice patterns and decision-making was investigated using an internet survey with 47-multiple choice items and vignette-based questions. Of 43 pediatric Htx cardiologists contacted, 28 (65%) responded. Respondents reported that an overall median 1-month survival of 73% (range 50-100%), 1-year survival of 70% (range 50-85%), 5-year survival of 50% (range 40-85%), and 10-year survival of 50% (range 25-85%) was adequate to offer Htx. Based on vignettes presented, 100% of those surveyed would offer Htx to a straightforward 12-year old with end-stage dilated cardiomyopathy and a 7-year old with hypoplastic left heart syndrome with protein losing enteropathy. Thirty percent of physicians would offer Htx to a patient status post a Fontan procedure with mutliple co-morbidities. Seventy-five percent of physicians would offer Htx despite proven non-adherence. Considerable variability exists in the practice patterns of pediatric heart transplant cardiologists with regards to decision-making while evaluating patients for listing. Disagreements among pediatric Htx cardiologists exist when there are concerns for non-adherence and associated multiple co-morbidities. Further work is needed to understand these variations and develop consensus for pediatric Htx organ allocation.

Psychosocial predictors of medication non-adherence in pediatric organ transplantation: A systematic review

Adherence to immunosuppressant medication is critical to health and quality-of-life outcomes for children who have received a solid organ transplant. Research on the psychological and social predictors of medication adherence is essential to the advancement of pretransplant assessments and transplant psychosocial services. Despite the importance of identifying risk factors, the literature remains limited regarding psychosocial predictors of non-adherence. A systematic search was conducted to identify studies of the psychosocial predictors of post-transplant medication non-adherence in pediatric solid organ transplantation. From 1363 studies identified in searches of empirical literature, a final sample consisted of 54 publications representing 49 unique studies. Findings regarding psychosocial predictors were inconsistent with non-adherence associated largely with adolescence, racial/ethnic minority status, and presence of mental health issues. Familial predictors of non-adherence problems included single-parent households, lower socioeconomic status, lower family cohesion, presence of family conflict, and poor family communication. Several studies reported an association between non-adherence and social pressures (eg, peer social interaction, wanting to feel normal) among adolescent transplant recipients. While significant methodological and substantive gaps remain in this body of knowledge, this review synthesizes current evidence for assessment for transplant clinicians and researchers.

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.

Neighborhood Socioeconomic Status and Outcomes Following the Norwood Procedure: An Analysis of the Pediatric Heart Network Single Ventricle Reconstruction Trial Public Data Set

BACKGROUND

Children with single ventricle heart disease require frequent interventions and follow-up. Low socioeconomic status (SES) may limit access to high-quality care and place these children at risk for poor long-term outcomes.

METHODS AND RESULTS

Data from the SVR (Pediatric Heart Network Single Ventricle Reconstruction Trial Public Use) data set were used to examine the relationship of US neighborhood SES with 30-day and 1-year mortality or cardiac transplantation and length of stay among neonates undergoing the Norwood procedure (n=525). Crude rates of death or transplantation at 1 year after Norwood were highest for patients living in neighborhoods with low SES (lowest tertile 37.0% versus middle tertile 31.0% versus highest tertile 23.6%, P=0.024). After adjustment for patient demographics, birth characteristics, and anatomy, patients in the highest SES tertile had significantly lower risk of death or transplant than patients in the lowest SES tertile (hazard ratio 0.62, 95% confidence interval, 0.40, 0.96). When SES was examined continuously, the hazard of 1-year death or transplant decreased steadily with increasing neighborhood SES. Hazard ratios for 30-day transplant-free survival and 1-year transplant-free survival were similar in magnitude. There were no significant differences in length of stay following the Norwood procedure by SES.

CONCLUSIONS

Low neighborhood SES is associated with worse 1-year transplant-free survival after the Norwood procedure, suggesting that socioeconomic and environmental factors may be important determinants of outcome in critical congenital heart disease. Future studies should investigate aspects of SES and environment amenable to intervention.

CLINICAL TRIAL REGISTRATION

URL:http://www.clinicaltrials.gov> http://www.clinicaltrials.gov. Unique identifier: NCT00115934.

Maintaining the Gift of Life: Achieving Adherence in Adolescent Heart Transplant Recipients

Since the beginning of United Network of Organ Sharing data collection in 1987, a total of 8,333 pediatric patients have received a heart transplant in the United States. Because these patients now have longer graft success with improved care and immunosuppression, many of them are entering adolescence and young adulthood. Primary care pediatric nurse practitioners need to be alert to the prevalence of noncompliance with treatment in heart transplant patients, which continues to be highest in adolescence. Low compliance in adolescence increases morbidity, contributes to decreasing quality of life, and is the leading reason for graft failure and mortality in this age group. This article will review common barriers to treatment adherence in the adolescent heart transplant patient, discuss the role of the primary care pediatric nurse practitioner in preventing noncompliance, and review strategies that the primary care pediatric nurse practitioner can implement to improve compliance in this patient population.

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.

Psychosocial predictors of medication adherence in pediatric heart and lung organ transplantation

Few studies have identified the psychosocial characteristics of those children and their families associated with future non-adherence to immunosuppressive medications following a heart or lung transplant. UNOS data and medical records information were used to test the association between patient and family psychosocial characteristics and medication adherence. Medication adherence outcomes were obtained using the physician assessments in the UNOS data and measured through patient-level standard deviation scores of immunosuppressive medication blood levels. Complete data were collected on 105 pediatric heart and lung transplant recipients and their families. Multivariate, stepwise analyses were conducted with each adherence outcome. Physician reports of adherence were associated with age of the child at transplantation, parental education, two-parent families, significant psychosocial problems, and the pretransplant life support status of the child. The resulting model (χ² =28.146, df=5, P<.001) explained approximately 39.5% of the variance in physician reports of adherence (Nagelkerke r² =.395). Blood level standard deviation scores were predicted by age at transplant (F=5.624, P=.02, r² =.05). Results point to the difficulties experienced by children and families when undergoing a heart or lung transplantation. Efforts to develop standardized and evidence-based pretransplant psychosocial assessments in pediatric populations are suggested, especially those surrounding familial risk factors.

The Influence of Race and Common Genetic Variations on Outcomes After Pediatric Heart Transplantation

Significant racial disparity remains in the incidence of unfavorable outcomes following heart transplantation. We sought to determine which pediatric posttransplantation outcomes differ by race and whether these can be explained by recipient demographic, clinical, and genetic attributes. Data were collected for 80 black and 450 nonblack pediatric recipients transplanted at 1 of 6 centers between 1993 and 2008. Genotyping was performed for 20 candidate genes. Average follow-up was 6.25 years. Unadjusted 5-year rates for death (p = 0.001), graft loss (p = 0.015), acute rejection with severe hemodynamic compromise (p = 0.001), late rejection (p = 0.005), and late rejection with hemodynamic compromise (p = 0.004) were significantly higher among blacks compared with nonblacks. Black recipients were more likely to be older at the time of transplantation (p < 0.001), suffer from cardiomyopathy (p = 0.004), and have public insurance (p < 0.001), and were less likely to undergo induction therapy (p = 0.0039). In multivariate regression models adjusting for age, sex, cardiac diagnosis, insurance status, and genetic variations, black race remained a significant risk factor for all the above outcomes. These clinical and genetic variables explained only 8-19% of the excess risk observed for black recipients. We have confirmed racial differences in survival, graft loss, and several rejection outcomes following heart transplantation in children, which could not be fully explained by differences in recipient attributes.

Socioeconomic Deprivation and Survival After Heart Transplantation in England

Background—

Socioeconomic deprivation (SED) is associated with shorter survival across a range of cardiovascular and noncardiovascular diseases. The association of SED with survival after heart transplantation in England, where there is universal healthcare provision, is unknown.

Methods and Results—

Long-term follow-up data were obtained for all patients in England who underwent heart transplantation between 1995 and 2014. We used the United Kingdom Index of Multiple Deprivation (UK IMD), a neighborhood level measure of SED, to estimate the relative degree of deprivation for each recipient. Cox proportional hazard models were used to examine the association between SED and overall survival and conditional survival (dependant on survival at 1 year after transplantation) during follow-up. Models were stratified by transplant center and adjusted for donor and recipient age and sex, ethnicity, serum creatinine, diabetes mellitus, and heart failure cause. A total of 2384 patients underwent heart transplantation. There were 1101 deaths during 17 040 patient-year follow-up. Median overall survival was 12.6 years, and conditional survival was 15.6 years. Comparing the most deprived with the least deprived quintile, adjusted hazard ratios for all-cause mortality were 1.27 (1.04–1.55; P =0.021) and 1.59 (1.22–2.09; P =0.001) in the overall and conditional models, respectively. Median overall survival and conditional survival were 3.4 years shorter in the most deprived quintile than in the least deprived.

Conclusions—

Higher SED is associated with shorter survival in heart transplant recipients in England and should be considered when comparing outcomes between centers. Future research should seek to identify modifiable mediators of this association.

Urgent listing exceptions and outcomes in pediatric heart transplantation: Comparison to standard criteria patients

BACKGROUND

United Network for Organ Sharing (UNOS) policy enables listing exceptions to avoid penalizing patients with waitlist mortality not captured by standard criteria. Outcomes among patients listed by exception have not been analyzed.

METHODS

We performed a retrospective analysis of pediatric (≤17 years of age, n = 4,706) listings (2006 to 2015) for primary, isolated heart transplantation within the UNOS data set, assessing Status 1A exception (n = 211, 4.5%) use across regions and patient characteristics and evaluating waitlist outcomes compared with candidates listed using standard criteria.

RESULTS

Death or removal for reason other than transplant did not differ between exception and standard criteria patients at 1 month (11.7% vs 16.2%, p = not statistically significant [NS]), 2 months (18.2% vs 29.0%, p = 0.11) or overall (16.1% vs 22.0%, p = NS) on the waitlist. Rates were higher than among Status 1B patients (1 month: 2.8%; 2 months: 5.6%; overall: 14.9%; p < 0.0001). The cumulative incidence of competing risks (transplantation, death/removal for reasons other than transplant and removal) did not differ when comparing Status 1A exception patients with Status 1A standard criteria patients. Use of 1A exceptions varied across UNOS regions (1.9% to 22.3%, p < 0.0001). Risk-adjusted modeling identified patients more (hypertrophic cardiomyopathy: odds ratio [OR] = 2.8, 95% confidence interval [CI] 1.5 to 5.0; restrictive cardiomyopathy: OR = 2.7, 95% CI 1.7 to 4.3) and less (low socioeconomic status: OR = 0.7, 95% CI 0.5 to 1.0) likely to use an exception. Use of exceptions was uncorrelated with regional outcomes.

CONCLUSIONS

Waitlist mortality among Status 1A exception patients is similar to that among those listed by standard criteria. However, variation in exception use across geography and demography may contribute to inequities in access to transplantation, particularly for those with low socioeconomic status. Standardization of practices may decrease regional variation and minimize inequities.

Risk factors for specific causes of death following pediatric heart transplant: An analysis of the registry of the International Society of Heart and Lung Transplantation

We sought to determine temporal changes in COD and identify COD-specific risk factors in pediatric primary HTx recipients. Using the ISHLT registry, time-dependent hazard of death after pediatric HTx, stratified by COD, was analyzed by multiphasic parametric hazard modeling with multivariable regression models for risk factor analysis. The proportion of pediatric HTx deaths from each of cardiovascular cause, allograft vasculopathy, and malignancy increased over time, while all other COD decreased post-HTx. Pre-HTx ECMO was associated with increased risk of death from graft failure (HR 2.43; p < 0.001), infection (HR 2.85; p < 0.001), and MOF (HR 2.22; p = 0.001), while post-HTx ECMO was associated with death from cerebrovascular events/bleed (HR 2.55; p = 0.001). CHD was associated with deaths due to pulmonary causes (HR 1.78; p = 0.007) or infection (HR 1.72; p < 0.001). Non-adherence was a significant risk factor for all cardiac COD, notably graft failure (HR 1.66; p = 0.001) and rejection (HR 1.89; p < 0.001). Risk factors related to specific COD are varied across different temporal phases post-HTx. Increased understanding of these factors will assist in risk stratification, guide anticipatory clinical decisions, and potentially improve patient survival.

High Risk of Graft Failure in Emerging Adult Heart Transplant Recipients

Emerging adulthood (17-24 years) is a period of high risk for graft failure in kidney transplant. Whether a similar association exists in heart transplant recipients is unknown. We sought to estimate the relative hazards of graft failure at different current ages, compared with patients between 20 and 24 years old. We evaluated 11 473 patients recorded in the Scientific Registry of Transplant Recipients who received a first transplant at <40 years old (1988-2013) and had at least 6 months of graft function. Time-dependent Cox models were used to estimate the association between current age (time-dependent) and failure risk, adjusted for time since transplant and other potential confounders. Failure was defined as death following graft failure or retransplant; observation was censored at death with graft function. There were 2567 failures. Crude age-specific graft failure rates were highest in 21-24 year olds (4.2 per 100 person-years). Compared to individuals with the same time since transplant, 21-24 year olds had significantly higher failure rates than all other age periods except 17-20 years (HR 0.92 [95%CI 0.77, 1.09]) and 25-29 years (0.86 [0.73, 1.03]). Among young first heart transplant recipients, graft failure risks are highest in the period from 17 to 29 years of age.

Creation of a quantitative score to predict the need for mechanical support in children awaiting heart transplant

BACKGROUND

Due to the availability of new devices, the use of ventricular assist devices (VADs) in children has been increasing; however, patient selection and optimal timing of device implantation in this population remains uncertain.

METHODS

A retrospective review of the United Network for Organ Sharing dataset identified 5,200 listings without mechanical circulatory support (MCS) for isolated pediatric heart transplant, 1995 to 2012. Patients were randomly divided into a derivation and validation cohort. A multivariable logistic regression model predicting the likelihood of death or need for MCS within 60 days was built using the derivation cohort and tested in the validation cohort. A simplified score (PedsMCS score) was developed and evaluated for accuracy.

RESULTS

The predictive model consisted of variables present at listing (age, albumin level, creatinine clearance, serum bilirubin, mechanical ventilation, and inotropic support). It had good predictive ability (C statistic 0.7304) within the validation cohort. The simplified PedsMCS score was also predictive (C statistic 0.7217) and there was a strong correlation between predicted and expected outcomes (r=0.91, p<0.0001). Patients with PedsMCS score 16 or greater had a significantly higher risk of death or MCS within 2 months (36.6%) than those with low scores (<6) (1.5%, p<0.0001). A single point increase in PedsMCS score was associated with a 16.7% increase in the risk of death or MCS with 2 months (p<0.0001).

CONCLUSIONS

We have developed and validated a simplified score to predict the need for MCS based on risk factors present at listing. This will provide more accurate prognostication in children awaiting heart transplant, and may improve patient selection.

Ventricular assist devices as a bridge-to-transplant improve early post-transplant outcomes in children

BACKGROUND

The use of ventricular assist devices (VADs) to bridge pediatric patients to transplant or recovery has been expanding. There are few current pediatric data assessing the impact of VAD support on post-transplant survival.

METHODS

We performed a retrospective review of all pediatric (≤18 years old, n = 4,028) transplants performed between 1995 and 2011 and contained within the United Network for Organ Sharing data set. Transplants were divided into three eras: early (1995 to 2002, n = 1,450); intermediate (2003 to 2007, n = 1,138); and recent (2008 to 2011, n = 1,440). VADs were present at transplant in 398 patients (9.8%). Outcomes among patients with and without VADs were assessed and compared across eras.

RESULTS

The use of VADs for bridge to transplant has increased (early 1.1%, intermediate 10.5%, recent 17.9%; p < 0.0001). Mean weight among VAD-supported patients (early 63.5 kg, intermediate 42.3 kg, recent 28.8 kg; p < 0.0001) has decreased during this period. VAD patients <10 kg had an increased risk of stroke (odds ratio [OR] = 4.9, 95% confidence interval [CI] 2.1 to 10.8) compared with non-mechanical support patients. In multivariable analyses, extracorporeal VADs were the only type of VAD associated with higher post-transplant mortality (OR = 3.0, 95% CI 0.8 to 10.6). Other types of VAD had lower mortality (OR = 0.5, 95% CI 0.2 to 1.0). Long-term survival was unaffected by the use of a VAD pre-transplant.

CONCLUSIONS

Pediatric patients bridged to transplantation with VADs are increasingly younger and smaller. Complication rates remain high among patients <10 kg. Early post-transplant survival among intracorporeal and paracorporeal VAD patients is excellent and better when compared with unsupported patients. The use of short-term support devices is associated with higher post-transplant mortality. Long-term survival is unaffected by VAD use.