Distribution of donor lungs in the United States: a case for broader geographic sharing.

OBJECTIVES

To evaluate the association between allocation of donor lungs by geographic sharing type (GST) and lung allocation score (LAS).

METHODS

UNOS data included lung transplant recipients between 5/4/05 and 09/30/15 (n = 17 416) grouped by GST of donor lungs: local, regional, or national. Recipients were stratified by LAS <50, 50-75, and >75. Kaplan-Meier analysis was used to assess five-yr survival.

RESULTS

The majority of lungs were shared locally (n = 9200; 52.8%) followed by nationally (n = 5356; 30.8%) and regionally (n = 2860; 16.4%). There was a significant difference in the mean LAS at transplant (local: 43.7 ± 15; regional: 49.5 ± 18.8; national 51 ± 19.4; p < 0.001). There was a significant association between GST and LAS (p < 0.001). The majority (n = 7431; 58.2%) of recipients with LAS <50 received local lungs. Recipients with LAS >75 received a majority of their organs from national (n = 881; 45.4%) and regional (n = 414; 21.6%) donors. Although statistically significant (p = 0.024), absolute decline in five-yr survival by GST in the national GST was only 1.1% compared to the local GST.

CONCLUSIONS

Nearly half of all lungs in the United States are allocated locally to recipients with an LAS <50. Additional studies should determine if organ sharing over broader geographies would improve waitlist outcomes.