Evaluating the Impact of HCT-CI-Age Score and Pre-Transplant Social Determinants of Health on Non-Relapse Mortality in a Modern Cohort with Post-Transplant Cyclophosphamide-Based GvHD Prophylaxis

Abstract

Allogenic hematopoietic transplantation (alloHCT) is the most promising curative treatment in AML/MDS, however the mortality after alloHCT due to nonrelapse mortality (NRM) was 22.3%(1). One of the causes of mortality after alloHCT is dependent on patient-level factors. Patient level factors can be from their comorbidity’s status, psychological and social determinants of health. To quantify patient comorbidity, clinician use HCT-CI-age to help them navigate what kind of GvHD prophylaxis or chemotherapy conditioning intensity suitable for patient. Other patient level factors such as social determinants of health are increasingly recognized as significant factors influencing patient transplant mortality outcomes. Currently, more healthcare providers are using prognostic evaluation such as Hematopoietic Stem Cell Transplant-comorbidity index (HCT-CI), The Composite Health Risk Assessment Model (CHARM), The Simplified Comorbidity Index (SCI), The European Group for Blood and Marrow Transplantation (EBMT) score which are focused on patient medical comorbidities yet fail to capture patient social determinants of health(2–4). We propose to evaluate the HCT-CI score and incorporate social determinants of health to create a better prognostication score that can assist clinician and health care professional to better manage patient care. Manuscript 1: HCT-CI-age has been a tool for clinicians to help decide the choice of conditioning and type of GvHD prophylaxis suitable for patients. Since its development in 2014, alloHCT care has been improving, thus reducing mortality outcomes. With this regard, many contradictory findings have been made regarding how helpful HCT-CI-age is in predicting NRM in modern-era transplants. To our knowledge, this is the first study to evaluate the association of HCT-CI-age and its individual components with NRM in a comprehensively characterized AML/MDS patient retrospective single center cohort undergoing transplantation with both post-transplant cyclophosphamide (PTCy) and non-PTCy-based GVHD prophylaxis Manuscript 2: Social determinants of health are known for their important association with patient NRM. Using SVI index created by CDC combining with patient caregiver status and distance from transplant center, we propose to explore the association of social determinants of health with NRM as an outcome. We hypothesize that patients with higher SVI, with non-spouse caregiver and longer distance of residence associates with higher non relapse mortality risk compared to the low SVI, with spouse caregiver and short distance in residence.