DDespite advances in treatment for multiple myeloma (MM), patients’ socioeconomic status (SES) is a significant factor in predicting survival rates, according to a wide-ranging review of studies on the disease.
Researchers from Greece performed a meta-analysis of 16 studies in the United States and worldwide to examine the correlation between MM survival and SES, and their findings were published in Mediterranean Journal of Hematology and Infectious Diseases.
Although SES is calculated based on education, social support, and income, the authors noted that it has shown to be a “surrogate” marker for differences in such factors as race/ethnicity, availability of new treatment options, access to health system facilities, and insurance coverage.
A meta-analysis of 10 studies involving 85,198 participants showed a better probability of being alive after 5 years for high-SES patients than low-SES patients (HR, 1.26; 95% CI, 1.13-1.31).
The authors also analyzed 6 studies from the United States focusing on MM that involved 89,807 participants, performing a synthesis of P values. They found an extracted P value of < .0001, reflecting a statistically significant association between low SES and overall survival across all ages and groups.
They said the disparities are likely to get worse. “Financial intoxication of myeloma care on health systems and patients is rising through the decades,” they wrote. “Therefore the gap in myeloma care between deprived and affluent patients is expected to widen in the future.”
This gap in survival rates exists despite advances in MM care over recent decades, with 50% of patients surviving beyond 5 years after diagnosis, the authors wrote. While autologous stem cell transplantation (ASCT) remains the most effective treatment, proteasome inhibitors, new immunomodulatory drugs, and anti-CD38 and anti-SLAM monoclonal antibodies have improved survival for both patients with newly diagnosed disease and those who have refractory/relapsed MM.
The investigators’ review also noted significant differences in OS for various racial/ethnic groups. For example, the incidence of myeloma in California is higher for African Americans than other races, with most patients affected in their earlier decades.
African Americans were also less likely to undergo ASCT and be treated with the proteasome inhibitor bortezomib (Velcade), “leading to a potential association with the worst prognosis,” the authors said. White American were 1.75 times (95% CI, 1.64-1.86; P = .01) more likely to undergo ASCT. Once patients received ASCT, however, the difference in survival between White and African Americans goes away.
One reason for disparities in myeloma care is the difference in participation levels in clinical trials for antimyeloma agents, the study said. Over the decades, the differences have narrowed but remain. African Americans, as well as those of Hispanic or Asian origin, are underrepresented in trials. For example, 99% of participants in the VISTA study were White, and the FIRST and MMY-3002 trials, among others, had 75% to 88% participants who were White.