Evaluation of the lung allocation score in highly urgent and urgent lung transplant candidates in Eurotransplant

Background: The purpose of the study was to investigate the impact of the lung allocation score (LAS) on mortality among highly urgent (HU) and urgent (U) lung transplant (LTx) candidates in Eurotransplant (ET) and to identify useful additional parameters (LASplus).

Methods: All adult LTx candidates for whom a first request for HU or U status was made in 2008 in ET were included (N = 317). Patients were followed until LTx, death on the waiting list (WL), delisting, or closure date (i.e., January 10, 2010). The relationship between the LAS/LASplus and waiting list, post-transplant, and overall mortality was assessed with a multivariate regression model. The LAS and LASplus were decomposed into their basic waitlist and post-transplant components.

Results: Waiting list mortality rate was 22% and 1-year post-transplant mortality rate was 34%. The waitlist component of the LASplus was significantly associated with waiting list mortality (hazard ratio [HR] 1.91, p = 0.021), whereas the LAS was not (p = 0.063). The post-transplant components of both scores were significantly associated with 1-year post-transplant mortality (LAS: HR 2.69, p = 0.005; LASplus: HR 2.55, p = 0.004). Both scores strongly predicted overall mortality (LAS: HR 1.65, p = 0.008; LASplus: HR 1.72, p = 0.005).

Conclusion: LAS accurately predicts overall mortality in critically ill transplant candidates and should therefore be considered as the basis for a new lung allocation policy in ET. An adjustment of the original LAS may be indicated to accurately predict waiting list mortality.