Baseline Lung Allograft Dysfunction: Real-World Data for an Emerging Early Posttransplant Clinical Phenotype.

Objectives: Baseline lung allograft dysfunction reflects suboptimal graft recovery and development after lung transplant and is characterized by a persistent low lung function in the first year. Despite its potential prognostic value, baseline lung allograft dysfunction remains insufficiently characterized or defined and thus underreported.

Materials and methods: In this retrospective cohort study, we analyzed 80 adult double-lung transplant recipients for the period January 2021 to December 2023. Baseline lung allograft dysfunction was defined as failure to reach a peak forced expiratory volume in 1 second and/or forced vital capacity ≥80% predicted on ≥2 pulmonary function tests at least 3 months apart within the first year. Patients with and without baseline lung allograft dysfunction were compared using demog-raphic, serial functional, and postopera-tive variables.

Results: Baseline lung allograft dysfunction occurred in 58.8% of patients. These individuals were younger (P = .044) and had significantly worse lung function at 12 months in absolute values for forced expiratory volume in 1 second (2.12 ± 0.65 vs 3.11 ± 0.82 L; P < .001) and predicted values (67.3 ± 16.2% vs 103.8 ± 23.8%; P < .001). Durations of intensive care unit stays and total hospital stays were longer in the group with baseline lung allograft dysfunction (P = .006), reflecting more complex early postoperative recovery. No significant differences were found in body mass index, sex, underlying diagnosis, acute rejection, or donor-specific antigen presence.

Conclusions: Baseline lung allograft dysfunction is a highly prevalent yet underrecognized early allograft dysfunction phenotype that is associated with impaired clinical recovery and prolonged intensive care unit stay and hospital stay. Systemic identification of baseline lung allograft dysfunction phenotype using serial pulmonary function testing enables early risk stratification and may inform future intervention strategies aimed to optimize graft recovery and long-term survival.