Impact of Travel Burden and Access to Care on Survival Following Pediatric Heart Transplantation in the Contemporary Regionalization Era

S. Sakowitz¹, S. Bakhtiyar², S. Mallick³, E. Aguayo⁴, R. Shemin³, P. Benharash^5
1UCLA David Geffen School of Medicine, Los Angeles, California ²University of Colorado, Aurora, Colorado ³UCLA, Los Angeles, California ⁴Harbor UCLA, Torrance, California ⁵UCLA Division of Cardiac Surgery, Los Angeles, California

Purpose: While regionalization has been proposed to improve outcomes and quality of pediatric heart transplantation(HT) care, some have suggested it may exacerbate travel burden and geographic disparities in access to care[1-4]. We sought to evaluate the impact of travel distance, socioeconomic status, and unequal healthcare access on survival following pediatric HT.

Methods: All first-time, isolated HT recipients < 18years from 2004-2023 were tabulated from the Organ Procurement and Transplantation Network, with follow-up through April 2024. Annual volume was computed for each program, with institutions performing ≥10 transplants/year considered High-Volume Centers(HVC). The haversine formula was used to compute travel distance to the transplanting center for each recipient. Recipients who faced distances in the highest quartile were categorized as Long-Distance (≥116miles). All others were considered Short-Distance. We utilized the Child Opportunity Index(COI) to account for neighborhood socioeconomic conditions[5].

To evaluate survival, we applied Kaplan-Meier time-to-event and Cox proportional hazard models. Covariates were automatically selected using the least absolute shrinkage and selection operator, and included patient age, sex, race, insurance, COI score, status at listing, functional status, ventilator or extracorporeal membrane oxygenation dependence, transplant indication, and year.

The primary outcome was survival at 5- and 10- years following heart transplantation. We secondarily considered allograft failure.

Results: Of 7,302 recipients, 1,991 (27%) were considered Long-Distance (Figure1A). Relative to Short-Distance, Long-Distance patients were of similar age, sex, and status at listing, but more commonly of White race (61 vs 50%, P< 0.001) and Medicaid insurance (51 vs 45%, P< 0.001). They more often underwent HT for congenital heart disease (54 vs 51%, P=0.04), and received care at HVC (49 vs 41%, P< 0.001; Table).

Following comprehensive risk-adjustment, Long-Distance was linked with comparable patient (HR 1.10, 95%Confidence Interval [CI] 0.93-1.31) and allograft survival at 5-years (HR 1.11, CI 0.93-1.32), but significantly greater mortality (HR 1.17, CI 1.03-1.36) and allograft failure at 10-years (HR 1.17, CI 1.01-1.36; Figure1B-1C).

Evaluating factors associated with traveling prolonged distances, we found patients treated at HVC faced a +33.6 mile adjusted increase in distance traveled to reach care (CI 21.2-45.9 miles). Further, Medicaid insurance coverage was linked with significantly increased travel distance (β+15.5 miles, CI 1.9-29.2; Reference: Private).

Finally, we considered outcomes among patients who reached HVC for care. Prolonged distance remained linked with greater patient mortality and allograft failure at 5- (Patient HR 1.36, CI 1.05-1.76; Allograft HR 1.40, CI 1.08-1.82) and 10-years (Patient HR 1.27, CI 1.02-1.59; Allograft HR 1.30, CI 1.04-1.63; Figure1D).

Conclusion: Patients traveling longer distances demonstrated inferior survival over 10-years of follow-up. Notably, survival disparities associated with extended travel distance persisted among patients treated at HVC. In the contemporary era of increasing regionalization of care, novel efforts are needed to ensure high-quality, and longitudinal, transplantation care is accessible to all patients.

Identify the source of the funding for this research project: None