Pre-hematopoietic stem cell transplant lung function and pulmonary complications in children.

Rationale: Pulmonary complications are a significant cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation.
Objectives: The relationship between pretransplant pulmonary function tests (PFTs) and development of post-transplant pulmonary complications in children was studied.
Methods: This is a retrospective single institution cohort study of 410 patients who underwent pretransplant PFT and were monitored to 10 years posttransplant.
Measurements and Main Results: Pulmonary complications were observed in 174 (42%) patients. Children with pulmonary complications had significantly lower forced expiratory flow at 25-75% of vital capacity (P = 0.02) derived using conventional predicted equations for age, and the Global Lung Initiative-2012 predicted equations (P = 0.01). T-cell depletion (P = 0.001), acute grade 3-4 graft-versus-host disease (P = 0.008), and chronic graft-versus-host disease (P = 0.01) increased risk for pulmonary complications. Patients who had pulmonary complications had a 2.8-fold increased risk of mortality (P < 0.0001). The cumulative incidence of death due to pulmonary complications was significantly higher in children who had low lung volumes, FRC less than 50% (P = 0.005), TLC less than 50% (P = 0.0002), residual volume less than 50% (P = 0.007), and T-cell depletion (P = 0.01). Lower FEV1 (P = 0.0005), FVC (P = 0.0005), TLC (P  <  0.0001), residual volume less than 50% (P = 0.01), and restrictive lung disease (P = 0.01) predicted worse overall survival.
Conclusions: Abnormal pretransplant PFT significantly increased risk after transplant. These patients may benefit from modified transplant strategies to reduce morbidity and mortality.