The global severity of chronic graft-versus-host disease, determined by National Institutes of Health consensus criteria, is associated with overall survival and non-relapse mortality.

BACKGROUND The 2005 National Institutes of Health Consensus Development Conference on chronic graft-versus-host disease proposed major changes in the classification and grading of severity of chronic graft-versus-host disease. DESIGN AND METHODS We aimed to study the association of the proposed chronic graft-versus-host disease classification and global severity with transplantation outcomes among a consecutive series of patients who received pharmacokinetically-targeted doses of intravenous busulfan and fludarabine conditioning followed by transplantation of allogeneic peripheral blood stem cells. RESULTS From a total cohort (n = 242) of patients surviving more than 100 days after hematopoietic stem cell transplantation, 181 (75% of those at risk) had some manifestations of graft-versus-host disease after day 100. Of these, at onset 13 (7%) had late acute graft-versus-host disease, 62 (34%) had classic chronic graft-versus-host disease, and 106 (59%) had the overlap subtype of chronic graft-versus-host disease. The global severity of the chronic graft-versus-host disease was mild in 25% of cases, moderate in 46%, and severe in 29%. Multivariable modeling demonstrated the independent association of global severity of chronic graft-versus-host disease with overall survival (moderate/severe versus mild; HR 2.9, 95% CI 1.8-4.7, P < 0.0001) and non-relapse mortality (moderate versus mild; HR 3.86, 95% CI 1.17-12.73, P = 0.03, and severe versus mild (HR 10.06, 95% CI 3.07-32.97, P < 0.001). The type of onset of progressive chronic graft-versus-host disease and the platelet count at the time of diagnosis of the disease were significantly associated with overall survival. The occurrence and severity of chronic graft-versus-host disease was also significantly associated with primary disease relapse. CONCLUSIONS Patients with moderate to severe chronic graft-versus-host disease, as determined by National Institutes of Health Consensus criteria, have an inferior overall survival and worse non-relapse mortality. Clinical and research advances are needed to improve the outcomes of affected patients.