Comparative Effectiveness of Single Versus Bilateral Lung Transplantation in Dually Listed Recipients

Objective: To compare outcomes of single(SLT) versus bilateral(BLT) lung transplantation among dually listed recipients hypothetically eligible for either treatment. Summary Background Data: Considerable debate remains regarding the added benefit of BLT versus SLT. Prior analyses were confounded by significant selection bias or limited in generalizability to the contemporary era; a randomized trial remains unlikely due to ethical concerns. Methods: Within the Organ Procurement and Transplantation Network, we considered all adults who were dually listed for SLT and BLT and underwent first-time lung allograft transplantation for idiopathic pulmonary fibrosis(IPF) or chronic obstructive pulmonary disease(COPD) in the US between 2017-2024. We applied target trial emulation and clone-censor weight methodology to emulate a prospective randomized trial comparing SLT versus BLT. Results: We tabulated 3,274 dually listed lung allograft recipients, of whom 1,026 were transplanted for COPD and 2,248 for IPF. Median follow-up was 24.5 months. COPD patient survival at five years was superior following BLT (61%[55-66%]) versus SLT (52%[46-58%, P =0.009). Meanwhile, among IPF patients, five year survival was 59%[54-63%] following BLT versus 56%[51-61%], P =0.009) after SLT. In a target trial emulation, among COPD patients, BLT remained associated with reduced mortality hazard (HR 0.67, CI 0.50-0.88). However, stratifying by age, SLT and BLT yielded comparable outcomes among patients ≥70years (HR 0.75, Credible Interval 0.38-1.37). Evaluating IPF recipients, after adjustment, BLT remained associated with comparable mortality hazard (HR 1.04, CI 0.85-1.26). No age-related effect was noted. Conclusions: Our findings suggest SLT could yield acceptable post-transplantation survival in select patients, while expanding access to this invaluable resource.