The Role of Social Determinants of Health in Pediatric Stem Cell Transplantation: Bridging Gaps in Care

Pediatric stem cell transplantation (SCT) is a life-saving intervention for various hematologic and immunologic conditions, yet data show significant disparities in access, outcomes, and resource utilization for this intervention. According to Lena Winestone, MD, MSHP, a pediatric blood and bone marrow transplant specialist at UCSF Benioff Children’s Hospitals, social determinants of health (SDOH) such as race, ethnicity, socioeconomic status (SES), and neighborhood poverty levels play a significant role in these disparities in care.¹

During a presentation at the American Society for Transplantation and Cellular Therapy (ASTCT) 4th International Conference on Toxicities of Transplantation and Cellular Therapy, Winestone explained that understanding these disparities is critical for developing equitable health care strategies and improving outcomes for all children undergoing SCT.¹

“Data from the [Center for International Blood and Marrow Transplant Research (CIBMTR)] looking at the impact that neighborhood poverty has on SCT in children [showed] that there was a difference in [transplant-related mortality (TRM)] simply based on where you were coming from,” said Winestone during her ASTCT presentation.¹

Data show that a child’s insurance status is independently associated with mortality after hematopoietic cell transplantation. Image Credit: © pingpao - stock.adobe.com

The CIBMTR data showed that children from high-poverty neighborhoods (defined as areas where ≥20% of persons below 100% federal poverty level [FPL]) experienced 5-year TRM at a rate of 25% vs 20% among those in low-poverty neighborhoods (defined as areas where <20% of persons are below 100% FPL) (P = .037).^1,2 However, Bona et al observed that neighborhood poverty exposure was not associated with children experiencing inferior overall survival (OS) after hematopoietic cell transplantation (HCT) for malignant disease.^1,2

Furthermore, neighborhood poverty exposure was not associated with relapse, acute graft-versus-host disease (aGVHD), chronic graft-versus-host disease (cGVHD), or infection through day 100 in children receiving transplants for malignant disease. For nonmalignant disease, Bona et al observed no association between neighborhood poverty exposure and OS, aGVHD, cGVHD, or infection through day 100.²

However, among children receiving transplants for malignant disease, both neighborhood poverty exposure and Medicaid insurance were associated with an increased risk of TRM.² In children insured by Medicaid, Bona et al observed that OS was significantly inferior (HR, 1.23; 95% CI, 1.07-1.41; P = .004) compared with those with private insurance, with an adjusted 5-year OS of 48% (95% CI, 44% to 52%) in children insured by Medicaid compared with 55% (95% CI, 52% to 58%) for those with private insurance.² Similarly, children insured by Medicaid (HR, 1.28; 95% CI, 1.07-1.53; P = .006) were significantly more likely to experience TRM than those with private insurance. Additionally, children insured by Medicaid experienced a 5-year cumulative incidence of TRM at 24% (95% CI, 20% to 27%), compared with 19% (95% CI, 17% to 21%) for those with private insurance.²

“That a child’s insurance status is independently associated with mortality after HCT for malignant disease is striking in the modern era,” wrote Bona et al.²

In the CIBMTR study cohort, children living in high-poverty neighborhoods were not only more likely to be insured by Medicaid (58% vs 32%), but they were also more likely to be Black (36% vs 17%) and Hispanic (35% vs 18%) when compared with those living in low-poverty neighborhoods.² Among these populations, Black children faced a 50% higher risk of overall mortality and a 65% increased risk of TRM, even after adjusting for factors such as insurance type, disease severity, donor characteristics, and year of transplant.¹

Analysis of the California Cancer Registry provides further insights, according to Winestone. Black patients spent an average of 49 days in the hospital during initial transplant admissions compared to 39 days for Hispanic patients and 35 days for non-Hispanic White patients. At 1 year post-transplant, Black patients averaged 12 hospital days for readmissions compared to 11 for Hispanic patients and 7 for non-Hispanic White patients. Furthermore, 39% of Black patients and 32% of Hispanic patients required more than 2 readmissions within the first year, compared to 25% of White patients. These findings reflect the higher burden of care and potential financial toxicity from readmissions experienced by minoritized populations.¹

Access to Transplantation

Access to SCT is a multifaceted issue that is also influenced by insurance coverage and SES, but is additionally influenced by donor availability. For example, Black children are significantly less likely to find suitable unrelated donors, with only 19% having a matched donor compared to 75% of White children, according to Winestone. Further, the likelihood of being able to receive a transplant is also affected by SES, and since Hispanic and Black patients are more likely to live in low-SES neighborhoods, this also contributes to disparities in access.¹

“Thinking about how SDOH relates to race and ethnicity, we see that the Black population and the Hispanic population are more likely to live in the lowest SES neighborhoods, and we also see that they're substantially more likely to have public insurance, with about 46% of Black patients having public insurance and 56% of Hispanic population in California having public insurance, compared to the White population where it's only about a quarter,” Winestone said. “We found that in California, Black patients were less likely to undergo SCT with the same diagnoses… So not only does neighborhood SES predict your likelihood of TRM, but it also predicts your likelihood of receiving a transplant in the first place.”¹

Newborn Screening and Donor Availability

One of the most promising interventions to reduce disparities is newborn screening, according to Winestone. For children with primary immunodeficiencies, early diagnosis through newborn screening has been associated with significantly improved outcomes, including reduced disparities in survival rates among Black patients. Further, while survival rates for symptomatic Black patients remain significantly lower than for White patients, newborn screening has helped to diminish this gap, suggesting the transformative potential of early detection and intervention. Early transplant, facilitated by timely diagnosis, also correlates with fewer infections and better outcomes, further emphasizing the importance of newborn screening and proactive care pathways.¹

Future Directions

Data show that SDOH influences SCT outcomes, access, and resource utilization in pediatric populations. Addressing these disparities requires multifaceted strategies, including policy interventions, community engagement, research and advocacy, and clinical innovation. To address these areas, targeted interventions to improve neighborhood SES and reduce the health impacts of poverty are needed, according to Winestone.¹

“As I think about how we would move forward, I think we do need to think about concrete referral pathways to ensure equitable access to care and really concrete guidelines,” Winestone said. “I think keeping a screening log of all the patients who you've evaluated should be a baseline characteristic that we collect on everybody to get at this denominator to really determine if we're delivering equitable access to care. I have been advocating for this for years, but I do think that we need to have a systematic and longitudinal approach to collecting SDOH data.”¹

Additionally, Winestone noted that using neighborhood measures to support collecting SDOH data is one approach, but an even better approach is talking to patients directly about what's going on with them.¹

“SDOH can impact our clinical care and how we deliver care, but can also impact our understanding of how SDOH impacts outcomes,” Winestone said. “[We should be] really thinking about interventions to address financial hardship as well. Just like we're designing interventions to address things like frailty, we really do need to be thinking about how we can directly intervene to impact patients experiencing financial hardship.”¹

REFERENCES

1. Winestone L. Access to and Financial Toxicity of Transplant and Cellular Therapies. Presented at: ASTCT 4th International Conference on Toxicities of Transplantation and Cellular Therapy; Philadelphia, PA; November 15-16, 2024.

2. Bona K, Brazauskas R, He N, et al. Neighborhood poverty and pediatric allogeneic hematopoietic cell transplantation outcomes: a CIBMTR analysis. Blood. 2021 Dec 2;138(22):2300. doi:10.1182/blood.2021012809