Lung Allocation Revisions Removing the DSA as First Zone of Offering Correlated with Decreased Wait List Mortality

Abstract

<h3>Purpose</h3> In November 2017 the lung allocation scheme was revised to eliminate DSA as the first geographic region for organ offers in attempt to minimize disparities in organ availability. This study was conducted to determine what impact allocation revisions had on waitlist time disparities and waitlist mortality in the United States. <h3>Methods</h3> The SRTR database was queried to determine waitlist times for all lung transplant recipients in the PRE era (Jan 2014 - Nov 2017) compared to the POST era (Dec 2017 - Feb 2021). Waitlist times were stratified into LAS quintiles. Transplant volumes were determined for each DSA in the PRE and POST eras. Waitlist mortality was determined in the PRE and POST eras. <h3>Results</h3> In the PRE era, waitlist times differed significantly between DSAs for each LAS quintile (p < 0.001) with greater than 10 fold differences for each LAS category between DSAs with the shortest and longest waitlist times. In the POST era, 10 fold waitlist time differences persisted between DSAs for each LAS category (p < 0.001) although ranking of DSAs by waitlist times changed. The number of annual transplants remained constant. Six DSAs performed at least 10 fewer transplants annually in the POST era compared to the PRE while seven DSAs performed at least 10 more. In the POST era, fewer patients in the first and fourth LAS quintiles received transplant while greater numbers of patients in the third and fifth quintiles received transplants. Patients delisted for mortality or condition deterioration decreased from 23.5% in the PRE to 20.1% in the POST eras (p<0.001). <h3>Conclusion</h3> Removing DSA as the first zone for donor lung allocation correlated with decreased waitlist mortality, but it remains unclear whether the UNOS policy change contributed to this reduced waitlist mortality.