Demographic, Clinical, and Allocation Shifts in the US Lung Transplant Waitlist: A National SRTR Study (2012-2023)

The US lung transplant system has undergone major demographic, clinical, and policy shifts over the past decade, including implementation of the Lung Allocation Score (LAS), the COVID-19 pandemic, and the 2023 transition to a continuous distribution ("post-LAS") framework. Contemporary longitudinal analyses integrating these transitions remain limited.

We performed a retrospective national time-series analysis of SRTR/OPTN adult lung transplant candidates from 2012 to 2023. Annual trends were examined across waitlist volume, age, sex, race/ethnicity, disease etiology, waiting time, allocation severity, height, blood type, and prior transplant status. Segmented (interrupted) time-series regression was used to assess inflection points associated with COVID-19 (2020) and the post-LAS transition.

From 2012 to 2023, new candidates increased from 2324 to 3385 (+45.7%), while total waitlist size rose from 3992 to 4365 (+9.3%). Candidates aged ≥65 years increased from 23.8% to 38.3%, whereas those aged 18 to 34 declined from 12.0% to 5.5%. Male predominance emerged (49.9% to 53.4%). White representation declined from 81.6% to 69.7%, with corresponding increases in Hispanic (6.3% to 14.1%) and Asian (1.7% to 3.5%) candidates. Restrictive lung disease increased from 47.2% to 67.9%, while cystic fibrosis declined from 10.7% to 2.0%. Waiting times compressed markedly, with candidates listed <90 days rising from 40.6% to 65.0% and those waiting ≥2 years declining from 16.2% to 4.2%. Legacy LAS distributions shifted toward higher acuity before 2023; 85.9% of candidates were categorized under the post-LAS framework in 2023. Height and blood type distributions remained stable; retransplant listings declined modestly.

The US lung transplant waitlist has undergone profound reconfiguration over the past decade, characterized by aging, racial diversification, etiologic dominance of restrictive lung disease, compressed waiting times, and increasing candidate acuity. The COVID-19 pandemic and post-LAS transition represent dominant structural inflection points with important implications for equity, efficiency, and policy evaluation.