Lung Allocation Score Thresholds Prioritize Survival After Lung Transplantation

Area of Science:

• Pulmonary Medicine
• Transplant Surgery
• Biostatistics

Background:

• The Lung Allocation Score (LAS) aims to prioritize lung transplant (LTx) candidates based on survival benefit.
• Criticism exists that the LAS may overly prioritize critically ill patients without a clear survival advantage.

Purpose of the Study:

• To determine if increasing LAS values beyond a certain threshold correlate with increased survival benefit from LTx.
• To identify optimal LAS thresholds for prioritizing LTx candidates.

Main Methods:

• Analysis of first-time adult LTx candidates (LAS ≥ 30) from the United Network for Organ Sharing Registry (May 2005-Dec 2016).
• Survival analysis comparing post-LTx outcomes with waitlist survival using proportional hazards regression.
• Modeling LTx survival benefit as a function of LAS.

Main Results:

• LTx demonstrated significant protection for patients with an initial LAS of 70-79 (HR 0.2).
• Survival benefit did not substantially increase for patients with LAS > 79.
• For cystic fibrosis patients, survival benefit plateaued around LAS 50.

Conclusions:

• Consistent survival benefit from LTx is observed for patients with LAS ≥ 70, supporting equal priority allocation.
• A lower LAS threshold for maximum priority is suggested for cystic fibrosis patients.