Publications

Neighborhood contextual factors are associated with liver transplant outcomes. We analyzed associations between neighborhood-level socioeconomic status and healthcare utilization for pediatric liver transplant recipients.

The social determinants of health contribute to adverse post-liver transplant outcomes. Identifying unmet social risks may enable transplant teams to improve long-term outcomes for at-risk children. However, providers may feel uncomfortable asking about household-level social risks in the posttransplant period because they might make their patients/families uncomfortable.

Children exposed to disproportionately higher levels of air pollution experience worse health outcomes. In this population-based, observational registry study, we examine the association between air pollution and graft failure/death in children following liver transplantation (LT) in the US. We modeled the associations between air pollution (PM) levels localized to the patient's ZIP code at the time of transplant and graft failure or death using Cox proportional-hazards models in pediatric LT recipients aged <19 years in the US from 2005-2015. In univariable analysis, high neighborhood PM was associated with a 56% increased hazard of graft failure/death (HR: 1.56; 95% CI: 1.32, 1.83; P < .001). In multivariable analysis, high neighborhood PM was associated with a 54% increased risk of graft failure/death (HR: 1.54; 95% CI: 1.29, 1.83; P < .001) after adjusting for race as a proxy for racism, insurance status, rurality, and neighborhood socioeconomic deprivation. Children living in high air pollution neighborhoods have an increased risk of graft failure and death posttransplant, even after controlling for sociodemographic variables. Our findings add further evidence that air pollution contributes to adverse health outcomes for children posttransplant and lay the groundwork for future studies to evaluate underlying mechanisms linking PM to adverse LT outcomes.

To evaluate associations between neighborhood income and burden of hospitalizations for children with short bowel syndrome (SBS).

Children from minoritized/socioeconomically deprived backgrounds suffer disproportionately high rates of uninsurance and graft failure/death after liver transplant. Medicaid expansion was developed to expand access to public insurance. Our objective was to characterize the impact of Medicaid expansion policies on long-term graft/patient survival after pediatric liver transplantation. All pediatric patients (<19 years) who received a liver transplant between January 1, 2005, and December 31, 2020 in the US were identified in the Scientific Registry of Transplant Recipients (N = 8489). Medicaid expansion was modeled as a time-varying exposure based on transplant and expansion dates. We used Cox proportional hazards models to evaluate the impact of Medicaid expansion on a composite outcome of graft failure/death over 10 years. As a sensitivity analysis, we conducted an intention-to-treat analysis from time of waitlisting to death (N = 1 1901). In multivariable analysis, Medicaid expansion was associated with a 30% decreased hazard of graft failure/death (hazard ratio, 0.70; 95% confidence interval, 0.62, 0.79; P < .001) after adjusting for Black race, public insurance, neighborhood deprivation, and living in a primary care shortage area. In intention-to-treat analyses, Medicaid expansion was associated with a 72% decreased hazard of patient death (hazard ratio, 0.28; 95% confidence interval, 0.23-0.35; P < .001). Policies that enable broader health insurance access may help improve outcomes and reduce disparities for children undergoing liver transplantation.

Liver transplantation for alcohol-related liver disease (ARLD) has increased. We examined temporal trends in ARLD listing practices by neighborhood deprivation and evaluated the impact of neighborhood deprivation on waitlist mortality.

Disparities exist in pediatric liver transplant (LT). We characterized barriers and facilitators to providing transplant and social care within pediatric LT clinics. This was a multicenter qualitative study. We oversampled caregivers reporting household financial strain, material economic hardship, or demonstrating poor health literacy. We also enrolled transplant team members. We conducted semistructured interviews with participants. Caregiver interviews focused on challenges addressing transplant and household needs. Transplant provider interviews focused on barriers and facilitators to providing social care within transplant teams. Interviews were recorded, transcribed, and coded according to the Capability, Opportunity, Motivation-Behavior model. We interviewed 27 caregivers and 27 transplant team members. Fifty-two percent of caregivers reported a household income <$60,000, and 62% reported financial resource strain. Caregivers reported experiencing (1) high financial burdens after LT, (2) added caregiving labor that compounds the financial burden, (3) dependency on their social network's generosity for financial and logistical support, and (4) additional support being limited to the perioperative period. Transplant providers reported (1) relying on the pretransplant psychosocial assessment for identifying social risks, (2) discomfort initiating social risk discussions in the post-transplant period, (3) reliance on social workers to address new social risks, and (4) social workers feeling overburdened by quantity and quality of the social work referrals. We identified barriers to providing effective social care in pediatric LT, primarily a lack of comfort in assessing and addressing new social risks in the post-transplant period. Addressing these barriers should enhance social care delivery and improve outcomes for these children.

Skeletal muscle index (SMI) remains a strong predictor of mortality in cirrhosis patients. However, the extent to which SMI varies by race/ethnicity has not been fully evaluated. Among 317 patients, 55% identified themselves as non-Hispanic White (NHW), 26% Hispanic White (HW), 13% Asian, and 6% Black. There was significant variation in SMI by race/ethnicity; median SMI was lowest in Asian and highest in Black patients. There were significant differences of sarcopenia by race/ethnicity using established SMI cutpoints: 48% NHW, 33% HW, 67% Asian, and 37% Black ( = 0.003). Using these cutpoints, SMI was significantly associated with waitlist mortality only in NHW patients but not in other racial/ethnic groups.

Social determinants of health (SDOH) are becoming increasingly recognised as mediators of human health. In the setting of metabolic dysfunction-associated steatotic liver disease (MASLD), most of the literature on SDOH relates to individual-level risk factors. However, there are very limited data on neighbourhood-level SDOH in MASLD.

Since the Final Rule regarding transplantation was published in 1999, organ distribution policies have been implemented to reduce geographic disparity. While a recent change in liver allocation, termed acuity circles, eliminated the donor service area as a unit of distribution to decrease the geographic disparity of waitlisted patients to liver transplantation, recently published results highlight the complexity of addressing geographic disparity. From geographic variation in donor supply, as well as liver disease burden and differing model for end-stage liver disease (MELD) scores of candidates and MELD scores necessary to receive liver transplantation, to the urban-rural disparity in specialty care access, and to neighborhood deprivation (community measure of socioeconomic status) in liver transplant access, addressing disparities of access will require a multipronged approach at the patient, transplant center, and national level. Herein, we review the current knowledge of these disparities-from variation in larger (regional) to smaller (census tract or zip code) levels to the common etiologies of liver disease, which are particularly affected by these geographic boundaries. The geographic disparity in liver transplant access must balance the limited organ supply with the growing demand. We must identify patient-level factors that contribute to their geographic disparity and incorporate these findings at the transplant center level to develop targeted interventions. We must simultaneously work at the national level to standardize and share patient data (including socioeconomic status and geographic social deprivation indices) to better understand the factors that contribute to the geographic disparity. The complex interplay between organ distribution policy, referral patterns, and variable waitlisting practices with the proportion of high MELD patients and differences in potential donor supply must all be considered to create a national policy strategy to address the inequities in the system.

We sought to determine whether race/ethnicity is associated with hospitalization outcomes among patients admitted with acute cholangitis.

Using in-depth interviews, we sought to characterize the everyday medical and social needs of pediatric liver transplant caregivers to inform the future design of solutions to improve care processes. Participants (parents/caregivers of pediatric liver transplant recipients) completed a survey (assessing socioeconomic status, economic hardship, health literacy, and social isolation). We then asked participants to undergo a 60-min virtual, semistructured qualitative interview to understand the everyday medical and social needs of the caregiver and their household. We intentionally oversampled caregivers who reported a social or economic hardship on the survey. Transcripts were analyzed using thematic analysis and organized around the Capability, Opportunity, Motivation-Behavior model. A total of 18 caregivers participated. Of the participants, 50% reported some form of financial strain, and about half had less than 4 years of college education. Caregivers had high motivation and capability in executing transplant-related tasks but identified several opportunities for improving care. Caregivers perceived the health system to lack capability in identifying and intervening on specific family social needs. Caregiver interviews revealed multiple areas in which family supports could be strengthened, including (1) managing indirect costs of prolonged hospitalizations (e.g., food, parking), (2) communicating with employers to support families' needs, (3) coordinating care across hospital departments, and (4) clarifying care team roles in helping families reduce both medical and social barriers. This study highlights the caregiver perspective on barriers and facilitators to posttransplant care. Future work should identify whether these themes are present across transplant centers. Caregiver perspectives should help inform future interventions aimed at improving long-term outcomes for children after liver transplantation.

Loneliness, "a subjective feeling of being isolated", is a strong predictor of adverse health. We characterized loneliness in patients with end-stage liver disease (ESLD) awaiting liver transplantation (LT).

Equity is a core principle in both pediatrics and solid organ transplantation. Health inequities, specifically across race, socioeconomic position, or geography, reflect a moral failure. Ethical principles of prudential life span, maximin principle, and fair innings argue for allocation priority to children related to the number of life years gained, equal access to transplant, and equal opportunity for ideal posttransplant outcomes. Iterative policy changes have aimed to narrow these disparities to achieve pediatric transplant equity. These policy changes have focused on modifying pediatric priority for organ allocation to eliminate mortality on the pediatric transplant waiting list. Yet disparities remain in pediatric liver transplantation at all time points: from access to referral for transplantation, likelihood of living donor transplantation, use of exception narratives, waitlist mortality, and inequitable posttransplant outcomes. Black children are less likely to be petitioned for exception scores, have higher waitlist mortality, are less likely to be the recipient of a living donor transplant, and have worse posttransplant outcomes compared with White children. Children living in the most socioeconomically deprived neighborhoods have worse posttransplant outcomes. Children living farther from a transplant center have higher waitlist mortality. Herein we review the current knowledge of these racial and ethnic, socioeconomic, and geographic disparities for these children. To achieve equity, stakeholder engagement is required at all levels from providers and health delivery systems, learning networks, institutions, and society. Future initiatives must be swift, bold, and effective with the tripartite mission to inform policy changes, improve health care delivery, and optimize resource allocation to provide equitable transplant access, waitlist survival, and posttransplant outcomes for all children.

To characterize associations between living in primary care shortage areas and graft failure/death for children after liver transplantation.

Racial/ethnic minority children have worse liver transplant (LT) outcomes. We evaluated whether neighborhood socioeconomic deprivation affected associations between race/ethnicity and wait-list mortality.

The social determinants of health, defined as the conditions in which we live, learn, work, and play, undoubtedly impact health outcomes. Social adversity in childhood perpetuates over the life course and has consequences extending into adulthood. This link between social adversity and adverse outcomes extends to children undergoing liver transplant, with children from socioeconomically deprived neighborhoods experiencing a greater burden of morbidity and mortality after transplant. Yet, we lack an in-depth understanding of how to address social adversity for these children. Herein, we lay out a strategy to develop and test interventions to address social adversity for children undergoing liver transplant. To do so, we believe that more granular data on how specific social risk factors (e.g., food insecurity) impact outcomes for children after liver transplant are needed. This will provide the liver transplant community with knowledge on the most pressing problems. Then, using the National Academies of Sciences, Engineering, and Medicine's framework for integrating social needs into medical care, the health system can start to develop and test health system interventions. We believe that attending to our patients' social adversity will realize improved outcomes for children undergoing liver transplant.

Neighborhood socioeconomic deprivation is associated with adverse outcomes after pediatric liver transplant. We sought to determine if this relationship varies by transplant center. Using SRTR, we included patients <18 years transplanted 2008-2013 (N = 2804). We matched patient ZIP codes to a deprivation index (range [0,1]; higher values indicate increased socioeconomic deprivation). A center-level patient-mix deprivation index was defined by the distribution of patient-level deprivation. Centers (n = 66) were classified as high or low deprivation if their patient-mix deprivation index was above or below the median across centers. Center quality was classified as low or high graft failure if graft survival rates were better or worse than the overall 10-year graft survival rate. Primary outcome was patient-level graft survival. We used random-effect Cox models to evaluate center-level covariates on graft failure. We modeled center quality using stratified Cox models. In multivariate analysis, each 0.1 increase in the patient-mix deprivation index was associated with increased hazard of graft failure (HR 1.32; 95%CI: 1.05, 1.66). When stratified by center quality, patient-mix deprivation was no longer significant (HR 1.07, 95%CI: 0.89, 1.28). Some transplant centers care for predominantly high deprivation children and maintain excellent outcomes. Revealing and replicating these centers' practice patterns should enable more equitable outcomes.

One in 10 people die awaiting transplantation from donor shortage. Only half of Americans register as organ donors. In this cross-sectional study, we evaluated population-level associations of neighborhood socioeconomic deprivation and racial segregation on organ donor registration rates. We analyzed state identification card demographic and organ donor registration data from 5 states to estimate the association between a neighborhood socioeconomic deprivation index (range [0, 1]; higher values indicate more deprivation) and a racial index of concentration at the extreme (ICE) (range [-1, 1]; lower values indicate predominantly black neighborhoods, higher values indicate predominantly white neighborhoods) on organ donor registration rates within a specified geography (census tract or ZIP code tabulation area [ZCTA]). Among 26 720 738 registrants, 32% of the sample were registered organ donors. At the census tract level, with each 0.1 decrease in the deprivation index, the organ donor registration rate increased by 6.8% (95% confidence interval [CI]: 6.6%, 7.0%). With each 0.1 increase in the racial ICE, the rate increased by 1.5% (95% CI: 1.5%, 1.6%). These associations held true at the ZCTA level. Areas with less socioeconomic deprivation and a higher concentration of white residents have higher organ donor registration rates. Public health initiatives should consider neighborhood context and novel data sources in designing optimal intervention strategies.

Neighborhood socioeconomic deprivation is associated with adverse health outcomes. We sought to determine if neighborhood socioeconomic deprivation was associated with adherence to immunosuppressive medications after liver transplantation.

Long-term outcomes remain suboptimal following pediatric liver transplantation; only one third of children have normal biochemical liver function without immunosuppressant comorbidities 10 years posttransplant. We examined the association between an index of neighborhood socioeconomic deprivation with graft and patient survival using the Scientific Registry of Transplant Recipients. We included children <19 years who underwent liver transplantation between January 1, 2008 to December 31, 2013 (n = 2868). Primary exposure was a neighborhood socioeconomic deprivation index-linked via patient home ZIP code-with a range of 0-1 (values nearing 1 indicate neighborhoods with greater socioeconomic deprivation). Primary outcome measures were graft failure and death, censored at 10 years posttransplant. We modeled survival using Cox proportional hazards. In univariable analysis, each 0.1 increase in the deprivation index was associated with a 14.3% (95% confidence interval [CI]): 3.8%-25.8%) increased hazard of graft failure and a 12.5% (95% CI: 2.5%-23.6%) increased hazard of death. In multivariable analysis adjusted for race, each 0.1 increase in the deprivation index was associated with a 11.5% (95% CI: 1.6%-23.9%) increased hazard of graft failure and a 9.6% (95% CI: -0.04% to 20.7%) increased hazard of death. Children from high deprivation neighborhoods have diminished graft and patient survival following liver transplantation. Greater attention to neighborhood context may result in improved outcomes for children following liver transplantation.

Poor adherence to medication following pediatric liver transplantation remains a major challenge, with some estimates suggesting that 50% of adolescent liver transplant recipients exhibit reduced medication adherence. To date, no gold standard has emerged to address this challenge; however, system interventions are most likely to be successful. We sought to implement a system to identify and address adherence barriers in a liver transplant clinic.

Machine learning analyses allow for the consideration of numerous variables in order to accommodate complex relationships that would not otherwise be apparent in traditional statistical methods to better classify patient risk. The SPLIT registry data were analyzed to determine whether baseline demographic factors and clinical/biochemical factors in the first-year post-transplant could predict ideal outcome at 3 years (IO-3) after LT. Participants who received their first, isolated LT between 2002 and 2006 and had follow-up data 3 years post-LT were included. IO-3 was defined as alive at 3 years, normal ALT (<50) or GGT (<50), normal GFR, no non-liver transplants, no cytopenias, and no PTLD. Heat map analysis and RFA were used to characterize the impact of baseline and 1-year factors on IO-3. 887/1482 SPLIT participants met inclusion criteria; 334 had IO-3. Demographic, biochemical, and clinical variables did not elucidate a visual signal on heat map analysis. RFA identified non-white race (vs white race), increased length of operation, vascular and biliary complications within 30 days, and duct-to-duct biliary anastomosis to be negatively associated with IO-3. UNOS regions 2 and 5 were also identified as important factors. RFA had an accuracy rate of 0.71 (95% CI: 0.68-0.74), PPV = 0.83, and NPV = 0.70. RFA identified participant variables that predicted IO-3. These findings may allow for better risk stratification and personalization of care following pediatric liver transplantation.

Age at diagnosis is a modifiable risk factor in outcomes after hepatoportoenterostomy in biliary atresia; however, distinguishing biliary atresia from other more common causes of prolonged neonatal jaundice can be difficult. To focus attention on diagnosis of biliary atresia, we analyzed secular trends in the age at diagnosis, and other factors that might influence outcome. We performed a retrospective analysis of 55 consecutive infants with biliary atresia presenting to a single academic pediatric center over 15-year period from 1990 to 2004. The median age at diagnosis was 60 days (range: 21-152). In recent era (2000-2004), the median age was 69.0 days, compared with 48.5 days (1990-1994) and 59.5 days (1995-1999), respectively. Consistent with previous studies, the median age at diagnosis of those with poor outcomes (death or liver transplant) exceeded those with good outcomes after the hepatoportoenterostomy (72 vs 52 days, P < .001). The lack of improvement, or a concerning trends toward an increase in the age at diagnosis of biliary atresia, is perhaps attributable to neonatal follow-up practices. Efforts to make an earlier diagnose of this important condition deserve wider application and study.