Impact of the 2018 Adult Heart Allocation Change on Pediatric Donor Offers and Waitlist Outcomes

Abstract

<h3>Purpose</h3> On October 18, 2018, UNOS made important revisions to the adult allocation system for heart transplant (HT). Although the revisions primarily affect the prioritization of adult HT candidates, it could impact pediatric candidates indirectly as adult candidates listed Status 1 or 2 take priority over pediatric Status 1B and 2 candidates. We sought to determine if there was any effect on donor offers, declines and waitlist outcomes for pediatric candidates in light of the adult allocation change. <h3>Methods</h3> All children <18 listed for HT within a 2-year period before and after the adult allocation revision was implemented were identified using OPTN data. Match-run analysis was also performed to examine the offer and decline rates. The primary endpoints were candidate transplantation and mortality rates. <h3>Results</h3> A total of 2,397 children met the study inclusion criteria, including 1,295 children listed before and 1,102 children listed after the adult policy change. The two cohorts were similar with respect to age, weight, cardiac diagnosis, ECMO, ventilator, VAD use, and insurance status. Nationwide offers to pediatric 1A candidates increased 34% per day, though center rejection of offers also rose a similar amount (41%). Pediatric candidates listed Status 1B and 2 also received more offers with a similar rise in center rejections, though the increases were smaller than for 1A candidates. Transplantation and mortality within 30-, 60- and 90-days did not change for 1A/1B candidates perhaps owing to the concomitant rise in center rejections of offers. There was a modest but significant decline in the likelihood of 30- and 60-day transplantation for patients listed at Status 2 following the change, though the likelihood of 90-day transplantation was comparable. <h3>Conclusion</h3> The 2018 changes to the adult allocation system have, if anything, resulted in an increased flow of donor offers to pediatric candidates, however transplantation rates for children listed 1A and 1B appear similar before and after the change, partly because the rise in offers was associated with a rise in offer rejections. For pediatric Status 2 candidates, transplantation was slightly lower at 30- and 60-days, but comparable at 90 days. More work is needed to reduce offer rejections to increase the transplantation rate for pediatric HT candidates.