Abstract No: e17554
Background: Advances in multiple myeloma (MM) therapies have improved overall survival (OS), however, not all population subgroups have benefited equally from these advances. Population-based studies suggest that black patients (pts) with MM have a much higher mortality rate than white pts, however, in several studies, after controlling for treatment, OS was similar or superior for black pts. This discrepancy suggests that the poorer outcomes observed in black pts are attributable to factors other than race, such as socioeconomic status (SES).
Methods: We performed retrospective chart review of 652 consecutive patients with a diagnosis of MM seen at the Siteman Cancer Center/Washington University School of Medicine from 2000 to 2009. Patients were eligible for analysis if their home address within 6 months of diagnosis was available. SES was approximated by median household income of each patient’s census tract from the American Community Survey (2012 5-year estimates). Comorbidities were categorized with the ACE-27. Results: 562 patients were eligible for analysis. The median age at diagnosis was 59 years (range 33-91); 55% were male; 26% were black. The median household income was $49,464.5 (range 11,917-163,958). The median follow-up was 49 months (range 0-165). Patients in the highest SES tertile (≥ $57,177 median household income) had a median OS of 62.8 months (mos) (95% CI 43.1-82.6 mos), compared to 53.7 mos (45.2-62.3 mos) and 48.6 mos (40.4-56.8 mos) for the middle and lowest tertiles, respectively (p =0.015). They were also less likely to have comorbidities at diagnosis (58% compared to 72% and 76%, p =0.007). Although black pts were more likely to be in in the lowest or middle tertiles than white pts (90% compared to 60%, p <0.001), OS and the prevalence of comorbidities were similar between the two groups. After controlling for severity of comorbidities, age, and race, SES was associated with OS [HR 0.84 (95% CI 0.65-1.10) for middle SES relative to lowest; HR 0.6 (95% CI 0.46-0.83) for highest SES relative to lowest].
Conclusions: Lower SES independently predicts poorer survival. Future studies will examine whether differences in MM disease markers at diagnosis or treatment account for this disparity.
Author(s): Mark A Fiala, Joseph D Finney, Jingxia Liu, Keith Stockerl-Goldstein, Michael H. Tomasson, Ravi Vij, Tanya Marya Wildes; Washington University School of Medicine in St. Louis, St. Louis, MO