Course of FEV(1) after onset of bronchiolitis obliterans syndrome in lung transplant recipients

RATIONALE: Bronchiolitis obliterans syndrome (BOS), defined by loss of lung function, develops in the majority of lung transplant recipients. However, there is a paucity of information on the subsequent course of lung function in these patients. OBJECTIVES: To characterize the course of FEV(1) over time after development of BOS and to determine the predictors that influence the rate of functional decline of FEV(1). METHODS: FEV(1)% predicted (FEV(1)%pred) trajectories were studied in 111 lung transplant recipients with BOS by multivariate, linear, mixed-effects statistical models. MEASUREMENTS AND MAIN RESULTS: FEV(1)%pred varied over time after BOS onset, with the steepest decline typically seen in the first 6 months (12% decline; p < 0.0001). Bilateral lung transplant recipients had significantly higher FEV(1)%pred at BOS diagnosis (71 vs. 47%; p < 0.0001) and at 24 months after BOS onset (58 vs. 41%; p = 0.0001). Female gender and pretransplant diagnosis of idiopathic pulmonary fibrosis were associated with a steeper decline in FEV(1)%pred in the first 6 months after BOS diagnosis (p = 0.02 and 0.04, respectively). A fall in FEV(1) greater than 20% in the 6 months preceding BOS (termed "rapid onset") was associated with shorter time to BOS onset (p = 0.01), lower FEV(1)%pred at BOS onset (p < 0.0001), steeper decline in the first 6 months (p = 0.03), and lower FEV(1)%pred at 2 years after onset (p = 0.0002). CONCLUSIONS: Rapid onset of BOS, female gender, pretransplant diagnosis of idiopathic pulmonary fibrosis, and single-lung transplantation are associated with worse pulmonary function after BOS onset.