Fig. 5: Mediation effect of early CMV reactivation on the relationship between Treg reconstitution and TRM.

a Mediation analysis showing that early CMV reactivation significantly mediated the association between Treg reconstitution at 2 months and TRM (ACME = –0.22, p = 0.032), accounting for 28.8% of the total effect. A significant direct effect of Treg reconstitution on TRM was also observed (ADE = –0.09, p = 0.048). b Sankey diagram illustrating the distribution of patients across Treg reconstitution groups (low vs. high), CMV reactivation status (no CMV vs. CMV), and transplant-related mortality (survival vs. death). Patients with high Treg reconstitution were more likely to avoid CMV reactivation and had a lower incidence of TRM. TRM transplant-related mortality, ACME average causal mediation effect, ADE average direct effect.