High Prevalence of Abnormal Baseline Lung Function in Pediatric and Young Adult Hematopoietic Stem Cell Transplant Recipients: A Report from the TRANSPIRE Study.

Summary

In a multicenter prospective cohort of 444 pediatric and young adult allogeneic HSCT recipients, 50.4% had abnormal baseline pulmonary function. Impairments in FEV1, FVC, and DLCO were substantial and persisted through 2 years, and baseline dysfunction was associated with lower overall survival (88.4% vs 95.9%).

Key Findings

• Baseline pulmonary dysfunction was present in 224/444 patients (50.4%).
• Median z-scores were significantly lower in the abnormal group for FEV1 (-2.3 vs -0.5), FVC (-2.0 vs -0.3), and DLCO (-2.4 vs -0.7); all p < 0.001.
• Impairments persisted through 2 years post-HSCT and were associated with lower overall survival (88.4% vs 95.9%); respiratory-related deaths included ARDS (n=3).

Clinical Implications

Incorporate comprehensive pretransplant pulmonary assessment (spirometry and DLCO) into routine HSCT workup, use results for risk stratification, consider optimization (pulmonary rehab, infection control) and conditioning regimen adjustments, and monitor longitudinally to mitigate long-term respiratory morbidity.

Limitations

• Observational design without randomization; potential residual confounding.
• Generalizability limited to participating pediatric/young adult centers; missing data possible.

Future Directions

Test pretransplant optimization strategies and conditioning modifications in interventional trials; extend follow-up beyond 2 years; integrate imaging and biomarkers to refine risk models.