Influence of pretransplantation restrictive lung disease on allogeneic hematopoietic cell transplantation outcomes.

We conducted a 15-year retrospective cohort study to determine the prevalence of restrictive lung disease before allogeneic hematopoietic cell transplantation (HCT), and to assess whether this was a risk factor for poor outcomes. A total of 2545 patients were eligible for the analysis. Restrictive lung disease was defined as a total lung capacity (TLC) < 80% of predicted normal. Chest x-rays and /or computed tomography (CT) scans were reviewed for all restricted patients to determine whether lung parenchymal abnormalities were unlikely or highly likely to cause restriction. Multivariate Cox proportional hazard and sensitivity analyses were performed to assess the relationship between restriction and early respiratory failure and nonrelapse mortality. Restrictive lung disease was present in 194 subjects (7.6%) before HCT. Among these cases, radiographically apparent abnormalities were unlikely to be the cause of the restriction in 149 subjects (77%). In unadjusted and adjusted analyses, the presence of pulmonary restriction was significantly associated with a 2-fold increase in risk for early respiratory failure and nonrelapse mortality, suggesting that these outcomes occurring in the absence of radiographically apparent abnormalities may be related to respiratory muscle weakness. These findings suggest that pulmonary restriction should be considered a risk factor for poor outcomes after transplantation.