Procedure Preference and Intention-to-Treat Outcomes after Listing for Lung Transplantation among U.S. Adults. A Cohort Study

RATIONALE: Bilateral lung transplantation is widely used to treat chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD), on the basis of an expectation of improved survival after transplantation. Yet, waiting list mortality is higher while awaiting bilateral transplantation. The net effect of procedure preference on overall survival is unknown. OBJECTIVES: To determine whether an unrestricted procedure preference is associated with improved overall outcomes after listing for lung transplantation. METHODS: We performed a retrospective cohort study of 12,155 adults with COPD or ILD listed for lung transplantation in the United States between May 4, 2005, and December 31, 2014. We defined a "restricted" procedure preference as listing for "bilateral transplantation only" and an "unrestricted" procedure preference as listing for any combination of bilateral or single lung transplantation. We used a composite "intention-to-treat" primary outcome that included events both before and after transplantation, defined as the number of days between listing and death, removal from the list for clinical deterioration, or retransplantation. RESULTS: In adjusted analyses, an unrestricted procedure preference was associated with a 3% lower rate of the primary intention-to-treat outcome in COPD (adjusted hazard ratio aHR, 0.97; 95% confidence interval CI, 0.89-1.07) and a 1% higher rate in ILD (aHR, 1.01; 95% CI, 0.94-1.08). There was no convincing evidence that these associations varied by age, disease severity, or the use of mechanical support. Among those with ILD and concomitant severe pulmonary hypertension, an unrestricted preference was associated with a 17% increased rate of the primary outcome (aHR, 1.17; 95% CI, 0.99-1.39). An unrestricted preference was consistently associated with lower rates of death or removal from the list for clinical deterioration and with higher rates of transplantation. Graft failure rates were similar among those listed with restricted and unrestricted preferences. CONCLUSION: When considering outcomes both before and after transplantation, we found no evidence that patients with COPD or ILD benefit from listing for bilateral lung transplantation compared with listing for a more liberal procedure preference. An unrestricted listing strategy for suitable candidates may increase the number of transplants performed without impacting overall survival.