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.