Abstract and Introduction
The aim of this study was to assess performance of the new lung allocation system in Germany based on lung allocation score (LAS). Retrospective analysis of waitlist (WL) outflow, lung transplantation (LTx) activity and 3-month outcomes comparing 1-year pre- and post-LAS introduction on December 10, 2011 was performed. Following LAS introduction, WL registrations remained constant, while WL mortality fell by 23% (p = 0.04). Reductions in WL mortality occurred in patients with cystic fibrosis (CF; −52%), emphysema (chronic obstructive pulmonary disease [COPD]; −49%) and pulmonary hypertension (PH; −67%), but not idiopathic pulmonary fibrosis (IPF; +48%). LTx activity increased by 9% (p = 0.146). Compared to pre-LAS, more patients with IPF (32% vs. 29%) and CF (20% vs. 18%) underwent transplantation and comparatively fewer with COPD (30% vs. 39%). Median LAS among transplant recipients was highest in PH (53) and IPF (49) and lowest in COPD (34). Transplantation under invasive respiratory support increased to 13% (in CF 28%, +85%, p = 0.017). Three-month survival remained unchanged (pre: 96.1% and post: 94.9%, p = 0.94). Following LAS implementation in Germany, reductions in waiting list size and WL mortality were observed. Composition of transplant recipients changed, with fewer COPD and more IPF recipients. Transplantation under invasive respiratory support increased. Reductions in WL mortality were most pronounced among CF and PH patients.
Lung transplantation (LTx) has become an established treatment option for patients with various end-stage lung diseases. Currently, approximately 3200 transplants are performed worldwide annually. Unfortunately, a shortage of donor organs leads to considerable numbers of patients dying on the waiting list before suitable organs become available. Efficient donor organ allocation remains crucial in optimizing donor use, to reduce waitlist (WL) mortality and to improve transplant outcomes. Currently, rules guiding allocation in most countries are based on urgency and transplant benefit, with survival benefit being the accepted primary goal.
Allocation policies are usually based on various factors, including geographical (regional, national, international), accumulated waiting time, audit-derived urgency criteria or individual clinical profile. Existing registry data are often used to assist individual assessment of urgency and transplant benefit in conjunction with clinical judgment. In most regions, national policy constitutes several of these criteria used in combination. Weighing of these factors, however, varies between the different models, with center-based regional distribution common in some European countries (e.g. Belgium, Austria, Italy, Spain and UK), while others place emphasis on waiting period or urgency (e.g. France, Switzerland and the Netherlands).
In May 2005, the United States replaced their waiting time-based system for allocating donor lungs with a system based upon the objectively derived lung allocation score (LAS) for patients of 12 years and older. The LAS is a numerical value used to assign relative priority in distributing donated lungs. The LAS evaluates several parameters of patient health to direct organ donation toward patients obtaining greatest benefit from LTx. The score is calculated from objective clinical measures of the patient's current health status to estimate survival probability and projected duration of 1-year survival with or without an LTx. LAS values range from 0 to 100, with higher scores indicative of greater predicted survival benefit, directing priority toward these patients.
Data comparing urgency-driven and LAS-based systems are limited. In December 2011, Germany replaced their previous allocation policy based on both urgency and waiting time with a scheme based on the LAS.
The aim of this study is to describe the performance of this new lung allocation system in Germany in its first use outside of the United States.
American Journal of Transplantation. 2014;14(6):1318-1327. © 2014 Blackwell Publishing