Impact of Social Determinants of Health on Access to Blood and Marrow Transplantation for Acute Myeloid Leukemia

Background: Allogeneic hematopoietic cell transplantation (HCT) is a curative therapy for adults with intermediate and high-risk acute myeloid leukemia(AML). Early referral to HCT and rapid donor identification have been associated with improved survival, but many patients have delays often for reasons unrelated to their disease.

Methods: The objective of this retrospective study was to identify the association between sociodemographic factors and delayed referral to HCT for adult patients with newly diagnosed AML (n=369) referred to our institution between 2019 and 2022. Data collected included disease characteristics, patient demographics (age, gender, race/ethnicity, zip-code, insurance type) and other social determinants of health as documented by social work evaluation. Zip-codes were used to estimate poverty level as defined by the American Community Survey, rural-urban continuum codes and distance to the transplant center. Outcomes collected included time from diagnosis to HLA typing, date to HCT consult and date to HCT (if done). Reasons for deferral of HLA typing or HCT were collected for those who did not proceed.

Results: The median age of the cohort was 63 (18-95) years, with 47% being 65 years or older. 43% were female, 10% were of race/ethnicity other than White, non-Hispanic, 45% were from nonmetropolitan areas, 46% resided in areas more than 60 miles from the transplant center and 44% lived in areas at or below the national poverty level. Public insurance was held by 39% of those younger than 65 years and 91% of those 65 years or older, and 2.5% were uninsured. One or more social determinants of health barriers were identified in 153 (41%) patients with the most common being lack of caregiver (7%), substance dependence (9%), financial stressors (12%) or psychiatric disorders interfering with daily living (14%). Referral for HLA typing was done for 42% of patients at a median time of 46 (0-280) days from diagnosis, and 21% within the first 6 weeks from diagnosis. Consultation for HCT was completed for 45% of patients at a median time of 58 (0-483) days from diagnosis, and 73% of those proceeded to HCT with a median of 154 (64-1030) days from diagnosis. Reasons documented for not proceeding with HLA typing and HCT consult included disease progression (37%), deemed as not indicated by treating oncologist (32%), comorbidities (16%), patient wishes (8%) and advanced age (4%). On multivariate analysis, non-disease related factors associated with lower odds of proceeding to HCT included age older than 70 years (OR 0.21, 95^th CI 0.10-0.40, p<0.0001) and non-private insurance (OR 0.42, 95^th CI 0.24-0.70, p=0.001), while factors such as gender, race/ethnicity, residing in a nonmetropolitan or poverty area, distance to the transplant center, and other social determinants of health barriers were not statistically significant.

Conclusions: Nearly half of adult AML patients referred to our institution received HCT consultation shortly after diagnosis, with nearly two thirds proceeding to treatment. HCT was accessible despite the geographical and sociodemographic challenges of our referral base. Efforts to reduce disparities, especially for older adults and those with public insurance, are essential to increase access in our region. The high proportion of patients proceeding to HCT after consultation highlights the need for improved early referral practices for AML patients for which transplant may be indicated. Expanding this analysis using national data could confirm our findings and help identify broader strategies to enhance HCT access.