Factors associated with waitlist clinical deterioration among United States lung transplant recipients under the continuous distribution system

Background: Lung continuous distribution (CD), implemented on March 9, 2023, changed the calculation and relative importance of medical urgency and posttransplant survival in prioritizing candidates for transplant. We aimed to identify factors associated with waitlist clinical deterioration and change in expected posttransplant survival from listing to transplant in the current system.

Methods: We used Organ Procurement and Transplantation Network (OPTN) data to conduct a retrospective study of 2,395 adult, lung-only transplant recipients added to the waiting list and transplanted between March 09, 2023, and March 08, 2024. We used multivariable linear regression to identify factors associated with change in waitlist area under the curve (WLAUC) and posttransplant area under the curve (PTAUC), representing expected survival (in days) without and with transplant, respectively.

Results: In multivariable analysis, longer waiting time (β=-1.3 per 7 days; p<0.001), male birth sex (β=-11; p=0.006), diagnosis group D (β=-27; p<0.001), and blood type O (β=-13; p<0.001) were associated with greater clinical deterioration from listing to transplant. Older (β=3.2 per 10-year increase in age; p=0.023) and taller (β=3.0 per 5 cm increase in height; p=0.003) recipients were less likely to clinically deteriorate from listing to transplant. Diagnosis group D (β=-4.7, p=0.032) and blood type O (β=-4.2, p=0.025) recipients had lower expected posttransplant survival at transplant compared to listing.

Conclusion: Our findings suggest the need to further investigate and address factors associated with waitlist clinical deterioration under CD. Future analysis of the effect of waitlist clinical deterioration on posttransplant outcomes under CD is needed.