A refined risk score for acute graft-versus-host disease that predicts response to initial therapy, survival, and transplant-related mortality.

To develop a novel acute graft-versus-host disease (GVHD) risk score, we examined the GVHD clinical stage and grade of 1723 patients at the onset of treatment with systemic steroids. Using clinical grouping, descriptive statistics and recursive partitioning, we identified poorly responsive, high-risk (HR) acute GVHD by the number of involved organs and severity of GVHD at onset. The overall response (complete response/partial response) rate 28 days after initiation of steroid therapy for acute GVHD was lower in the 269 patients with HR-GVHD than in the 1454 patients with standard risk (SR)-GVHD (44% [95% confidence interval (CI) 38% to 50%] versus 68% [95% CI, 66% to 70%], P