Fig. 3.

Comparison of pre-transplant serum levels of free IL-18 according to different non-relapse causes of death of patients of the training and the validation cohort in the first post-transplant year.

Non-relapse causes of death were grouped into four categories: severe infection/sepsis, cardiovascular events (CVE, including haemorrhage), death due to acute GVHD (i.e. lethal complications of acute GVHD and/or its treatment), and unknown causes. Median pre-transplant serum levels of free IL-18 were compared to patients not succumbing to NRM and among each category.

(A, B) In both the training and the validation cohort, median pre-transplant serum levels of free IL-18 (611 and 495 pg/mL, respectively) were most pronounced in patients who succumbed to severe infectious complications. Box plots are depicted. Number of patients/events for each group is indicated. P values were derived by Mann-Whitney U test.

(C, D) When NRM causes were compared between the first (Q1) and fourth quartile (Q4) of the pre-transplant IL-18 distribution, in both cohorts, the proportion of NRM events due to severe infections was higher in patients of the upper quartile of the pre-transplant IL-18 distribution.

Abbreviations: CV, cardiovascular; GVHD, graft-versus-host disease; IL-18, interleukin-18; Q1 and Q4, first and fourth quartile of the pre-transplant free IL-18 distribution, respectively.