TRANSPL CELL THER

Background: Allogeneic hematopoietic stem cell transplantation (HSCT) is a potentially curative treatment for hematologic diseases but remains associated with substantial morbidity and non-relapse mortality (NRM). The impact of adverse social factors on transplant outcomes in universal healthcare settings remains incompletely defined.

Methods: We conducted a retrospective single-center cohort study including 286 adults undergoing first allogeneic HSCT between 2012 and 2022. Three adverse social determinants were assessed at baseline: communication barriers, financial hardship, and living alone. Outcomes included overall survival (OS), NRM, graft-versus-host disease (GVHD), and cause-specific mortality. Multivariable models adjusted for age, HCT-CI, disease status, conditioning intensity, and donor type.

Results: The presence of ≥1 adverse social determinant was independently associated with inferior OS (HR 2.39, 95% CI 1.62-3.53; p<0.001) and higher NRM (HR 2.68, 95% CI 1.74-4.12; p<0.001). A dose-response relationship was observed with increasing numbers of adverse factors. Patients with adverse social determinants had higher cumulative incidence of acute grade II-IV GVHD (43% vs 30%, p=0.005) and moderate/severe chronic GVHD (p=0.002), as well as more infection-related deaths (28.6% vs 17.6%, p=0.047). The magnitude of the association was comparable to established prognostic factors.

Conclusions: Adverse social determinants are independently associated with inferior survival, increased GVHD risk, and higher NRM after allogeneic HSCT. Even within a universal healthcare system, social disadvantage significantly influences post-transplant outcomes and supports systematic identification of social risk and targeted supportive interventions.