The ISHLT chronic lung allograft dysfunction consensus criteria are applicable to pulmonary chronic graft-versus-host disease

Pulmonary chronic graft-versus-host disease (PcGVHD) is a devastating complication of allogeneic hematopoietic stem cell transplant (HCT). The 2014 National Institutes of Health cGVHD consensus criteria (NIH criteria) only captures bronchiolitis obliterans syndrome (BOS). In this study, we adapted the 2019 International Society for Heart and Lung Transplantation (ISHLT) criteria of chronic lung allograft dysfunction (CLAD) to define novel phenotypes of PcGVHD and compared the performance of this criteria with the NIH criteria to identify patients with high-risk PcGVHD. We reviewed consecutive patients in a cGVHD natural history protocol (#NCT00092235) and adapted the 2019 CLAD criteria (the adapted criteria) to define PcGVHD as post-HCT forced expiratory volume at 1 second < 80% predicted value, with 4 phenotypes: obstructive, restrictive, mixed obstructive/restrictive, and undefined. An independent adjudication committee evaluated subjects for diagnosis and phenotyping. We identified 166 (47.4%) patients who met the adapted criteria, including obstruction (n = 12, 3.4%), restriction (n = 67, 19.1%), mixed obstruction/restriction (n = 47, 13.4%), and undefined (n = 40, 11.4%). In these patients, less than half (n = 78) met the NIH criteria for BOS (NIH+); the rest (n = 88) did not (NIH-). The NIH- subjects showed increased risk of death compared with those without PcGVHD (hazard ratio = 1.88, 95% confidence interval = 1.20-2.95; P = .006) that was similar to NIH+ subjects (P = .678). Our study demonstrated the potential of the adapted criteria in identifying patients with high-risk PcGVHD that have been missed by the NIH criteria. The adapted criteria could become a valuable tool to better phenotype and study lung disease in cGVHD.