Race, Socioeconomic Status, and Time to Transplantation in Multiple Myeloma

Race, Socioeconomic Status, and Time to Transplantation in Multiple Myeloma

Background: Multiple myeloma is the most common hematologic malignancy in blacks. Previous studies have found that black patients undergo autologous stem cell transplant (ASCT) less frequently than their white counterparts, though the reasons for this have not been fully elucidated. To identify whether racial differences in timing of referrals to transplant centers and transplantation may play a role in this observed disparity, we analyzed data from transplants undergone at The Mount Sinai Hospital between 2011 and 2016.

Methods: We retrospectively analyzed 416 black and white patients who received their first autologous stem cell transplant for multiple myeloma at The Mount Sinai Hospital between 2011 and 2016. We compared the time from initial diagnosis to stem cell harvest and the time from harvest to transplant between the two groups while controlling for age, socioeconomic status, and functional status.

Results: In total, 264 white patients and 152 black patients were identified as receiving their first transplant between 2011 and 2016. Data regarding each patient's demographic, date of diagnosis, date of harvest and transplant, and functional status were available. Age, socioeconomic status (as assessed through census data of median income of the patients' zip code), and functional status were considered possible confounders. Linear regression analysis was used to assess differences in transplant timing between races while controlling for these factors. We found that between racial groups, neither the time from diagnosis to harvest (528 days vs. 406 days respectively, p=.95) nor the time from harvest to transplant (113 days vs. 150 days respectively, p=.31) was significantly different. Age and socioeconomic status also did not significantly affect either time point, although patients with higher socioeconomic status had a decreased time from diagnosis to harvest which approached significance (p=0.07) regardless of their race. Finally, better functional status was associated with a shorter time from diagnosis to harvest (p=0.003).

Conclusion: Based on these findings, race and socioeconomic status did not significantly affect expediency of referral to and completion of transplantation following initial disease diagnosis. Further studies are needed to clarify the factors contributing to observed differences in ASCT utilization between blacks and whites.