Understanding Barriers to Hematopoietic Cell Transplant (HCT) Access: Socio-Demographic Characteristics and Area Deprivation Index (ADI) of Patients Referred to the National Institutes of Health (NIH) for HCT

Background:

Hematopoietic Cell Transplant (HCT) is a potential cure for many hematologic malignancies but is unfortunately resource intensive. In the U.S., health insurance is generally a requirement to receive HCT, and prior studies have identified patient socio-demographic factors to be associated with decreased access and utilization of HCT. Area Deprivation Index (ADI) is a validated comprehensive measure of socioeconomic status based on zip code, and higher ADI is associated with increased cancer mortality. The objective of this study is to characterize the socio-demographic factors and ADI of patients who successfully underwent HCT at the NIH, a research hospital which does not require health insurance, to understand the barriers to HCT access outside of insurance status. Defining barriers is important in addressing disparities in cancer care and improving patient outcomes.

Methods:

We conducted a retrospective review of patients with hematologic malignancies referred to the Center for Immuno-Oncology (CIO)-HCT team at the NIH between 1/1/2020-12/31/2022, with review of post-referral outcomes through 12/31/2023. Data was analyzed descriptively using GraphPad Prism v10. This study included review of patients referred for IRB-approved clinical trials NCT04959175, NCT03983850, NCT05327023, NCT05436418, NCT03922724, NCT05470491.

Results:

331 patients were referred to the CIO-HCT team during the 3-year study period, with 87 (26%) reaching HCT at NIH. Of these 331 patients, 240 (72%) were sufficiently engaged in the referral process to be assigned a medical record number (MRN). Of the 91 that did not get an MRN, 40% were referred in 2020, 36% in 2021, and 24% in 2022. Of the 240 patients that obtained an MRN (MRN-referrals) 148 were male and 92 were female, with comparable HCT rates (35% vs. 37%, respectively). Of MRN-referrals with known marital status, 110 were married and 36% underwent HCT; 96 identified as single/divorced and 46% underwent HCT. Among the MRN-referrals, 53% were Hispanic, 24% were non-Hispanic White, and 14% were Black. 41% of Black patients underwent HCT, compared to 39% Hispanics and 30% non-Hispanic White patients. 55% of MRN-referrals that underwent HCT were non-English speaking. Median age of patients who underwent HCT was 44 years (range 13-71 years); 41% were <40 years.

Median time from referral to HCT was 137 days (range 32-1377 days). Time from referral to HCT was significantly longer for non-English speaking patients (191 days vs. 116 days; p=0.0014) and single/divorced patients (163 days vs. 127 days; p=0.04).

Median income by zip code for all patients who received HCT and lived in the U.S. (N=78) was $89,797. Single/divorced patients who received HCT lived in areas with significantly lower zip code median income compared to married patients who received HCT ($83,261 vs. $104,091; P=0.03) and patients <40 years who received HCT also lived in areas with significantly lower median income compared to those >40 years of age ($83,360 vs. $101,374; p= 0.03).

Median ADI for all transplanted patients was 38 (range 1-99). ADI was significantly higher for male vs. females (47 vs. 23; p=0.02), single/divorced vs. married (51 vs. 20; p=0.002), non-English-speaking patients vs. English-speaking patients (46 vs. 24; p=0.03), and patients aged <40 years vs. > 40 years (53 vs. 24.5, p=0.015). There were no ADI differences by race/ethnicity.

Median distance from home address to the NIH was 283 miles; there was no significant differences in median distance travelled across groups.

Conclusion:

Without health insurance as a requisite, 26% of referred patients successfully underwent HCT during the study period. There was a higher early disengagement rate in 2020, perhaps due to the SARS CoV-2 pandemic. Successful referrals did not differ by race/ethnicity, sex, or marital status, but time from referral to HCT was significantly longer for patients whose language was not English and for single/divorced patients. Transplanted patients who were male, non-English speaking, single/divorced, and <40 years of age had lower socioeconomic status, but these factors did not affect the successful receipt of HCT. Therefore, when insurance is not a barrier, high rates of underrepresented minorities and non-English speaking patients can successfully reach HCT, although delays exist. Future work will delve further into socio-demographic differences in HCT access.