Poor outcomes for children on the wait list at low-volume kidney transplant centers in the United States

Background: Low case volume has been associated with worse survival outcomes in solid organ transplantation. Our aim was to analyze wait-list outcomes in conjunction with posttransplant outcomes. Methods: We studied a cohort of 11,488 candidates waitlisted in the Organ Procurement and Transplantation Network (OPTN) for pediatric kidney transplant between 2002 and 2014, including both deceased- and living-donor transplants; 8757 (76 %) candidates received a transplant. Candidates were divided into four groups according to the average volume of yearly transplants performed in the listing center over a 12-year period: more than ten, six to nine, three to five, and fewer than three. We used multivariate Cox regression analysis to identify independent risk factors for wait list and posttransplant mortality. Results: Twenty-seven percent of candidates were listed at low-volume centers in which fewer than three transplants were performed annually. These candidates had a limited transplant rate; only 49 % received a transplant versus 88 % in high-volume centers (more than ten transplants annually) (p < 0.001). Being listed at a low-volume center showed a fourfold increased risk for death while on the wait list [hazard ratio (HR) 4.0 in multivariate Cox regression and 6.1 in multivariate competing risk regression]. It was not a significant risk factor for posttransplant death in multivariate Cox regression. Conclusions: Pediatric transplant candidates are listed at low-volume transplant centers are transplanted less frequently and have a much greater risk of dying while on the wait list. Further studies are needed to elucidate the reasons behind the significant outcome differences.