Understanding Sociodemographic Barriers in Hematopoietic Stem Cell Transplantation Among Patients with Hematologic Malignancies: Insights from a North Carolina Cohort

Background: Hematopoietic Stem Cell Transplantation (HCT) is a life-saving treatment for many patients with hematologic malignancies. Disparities persist across the transplant continuum. We hypothesize that sociodemographic factors disproportionately impact referral rates and completion of HCT. Understanding these disparities is essential for developing effective strategies to improve HCT access and mitigating healthcare inequities among patients with hematologic malignancies. This study assesses how social factors are associated with referral by primary hematologists, patient attendance at HCT evaluation, and receipt of HCT among North Carolina residents within our catchment area. Method: This retrospective study utilized data covering July 2019 to June 2022 from the North Carolina Central Cancer Registry (NCCCR) and Duke Cancer Institute (DCI) for adults aged 19-79 with HCT-eligible hematologic malignancies in 67 North Carolina counties designated as DCI's primary catchment area. Cohort 1includes NCCCR-Eligible patients (N = 8,557)-eligible for HCT in the NCCCR dataset. Cohort 2 includes Duke Referred patients (N = 761)-referred to Duke for HCT, further divided into: 2A) Referral Only (N = 124)-referred but did not receive an appointment; 2B)Appointment Only (N = 471)-had an appointment but did not undergo HCT; 2C) Transplanted (N = 166)-received HCT. Statistical analyses included chi-square, ANOVA, Wilcoxon Signed Rank tests, and logistic regression. Referrals to other centers within the DCI catchment and out-of-state counties were excluded. Result: NCCCR eligible vs. Duke Referred (Cohort 1 vs 2): Duke-referred patients were younger (median age 64 vs. 66 years, p = 0.004), had a higher percentage of African Americans (30% vs. 24%, p < 0.001), and had higher median income ($67,000 vs. $58,546, p < 0.001). They also had better access to resources (lower social vulnerability: 0.66 vs. 0.68, p < 0.001) and higher private insurance coverage (50% vs. 31%, p < 0.001). Additionally, a higher proportion of Duke-referred patients had Multiple Myeloma (48% vs. 28%, p < 0.001) and a lower proportion had Lymphoma (28% vs. 43%, p < 0.001) compared to the NCCCR cohort. Referral Only vs. Appointment Only (Cohort 2A vs 2B): Non-Caucasian/Non-African-American patients were less likely to attend their initial evaluation appointments (OR 0.35, 95% CI[0.19-0.66], p < 0.001), as were those with non-private or non-Medicare insurance (OR 0.45, 95% CI [0.22-0.96], p = 0.032). Although the Referral Only cohort had a higher proportion of African Americans (37% vs. 30%, p = 0.004) and showed a trend toward greater overall vulnerability (0.73 vs. 0.66, p = 0.045), these differences were not significant in multivariate analysis (African Americans: OR 0.66, 95% CI [0.42-1.06], p = 0.082; overall vulnerability: OR 0.02, 95%CI [0.00-1,484], p = 0.50). Other factors, including age, gender, income, and RUCA status, did not affect appointment attendance. Appointment-Only vs. Transplant Receipt (Cohort 2B vs 2C): Patients who only attended the initial appointment were older (median age 65 vs. 62 years, p = 0.002) and had a lower proportion under 65 (48% vs. 61%, p < 0.001). Multivariable analysis showed less likely receipt of transplant after appointment for patients >=70 years of age (vs. <=60, OR 0.34, 95% CI [0.18-0.62], p < 0.001). A higher proportion of those without a transplant had Medicare insurance (44% vs. 33%, p = 0.002), but this difference did not show clinical significance in multivariate analysis (OR 0.84, 95% CI [0.53-1.31], p = 0.40). However, those with non-private or Medicare insurance who attended the initial evaluation appointment had a higher likelihood of proceeding to HCT (OR 2.54, 95% CI [1.20-5.35], p = 0.014). Conclusion: Our analysis reveals barriers for non-Caucasian and non-African American patients and those with non-private or Medicare insurance, impacting access to initial HCT evaluations. While these factors hinder progression to evaluation, overcoming early barriers may improve access to HCT. To ensure equity, we must address insurance disparities, implement financial assistance programs, and tailor outreach for minoritized racial groups. These steps are crucial for achieving equitable access to HCT therapy for all patients.