Racial differences in treatment and survival among older patients with multiple myeloma

Treatments for multiple myeloma (MM) have evolved over time and improved MM survival. While racial differences in MM treatment and prognosis between non-Hispanic African American (NHAA) and non-Hispanic White (NHW) patients are well-established, it is unclear whether they have persisted after the introduction of novel agents.

Using the Surveillance, Epidemiology, and End Results-Medicare linked database, our study investigated racial difference in the receipt of treatment within 1 year following diagnosis and assessed survival outcomes among Medicare beneficiaries (≥66 years) diagnosed with MM from 2007 to 2017. We applied multivariable Cox proportional hazards models to estimate the association between race and survival and presented hazard ratios (HRs).

Of 2094 NHAA and 11,983 NHW older patients with MM, 59.5% and 64.8% received treatment during the first year, respectively. Discrepancy in the proportion of patients receiving treatment between the two groups increased from 2.9% in 2007 to 2009 to 6.9% in 2014-2017. After controlling for relevant factors, patients who received treatment within the first year had lower mortality than those who did not (HR = 0.90, 95% confidence interval [CI]: 0.86-0.94). NHAA patients had a lower probability to receive treatments during the first year than NHW patients (HR = 0.91, 95% CI: 0.85-0.97) but had lower mortality (HR = 0.94, 95% CI: 0.88-1.00). The lower mortality was only observed among patients who received no treatment (HR = 0.84, 95% CI: 0.77-0.93); NHAA and NHW patients who received treatment had similar survival (p = 0.63).

The increasing racial disparity in treatment utilization over time is concerning. Efforts are needed to eliminate the barriers of receiving treatment.