Enrollment on Systemic Therapy for Myeloma Affected by Race/Sex

Socioeconomic factors were found to play a significant role in perpetuating disparities in systemic therapy enrollment for patients with multiple myeloma, according to a study published in Hematology/Oncology and Stem Cell Therapy.

In particular, therapy enrollment was significantly impacted by factors such as race and sex (P <.005). Additionally, poor survival was associated with factors including advanced age, earlier year of diagnosis, lack of insurance or Medicaid, and higher comorbidity (HR >1). However, characteristics such as female, non-Hispanic Black race, higher income, and recipt of treatment at an academic center were associated with improved survival (HR <1).

“Disparities in [multiple myeloma] exist and are caused by a complex interplay of multiple factors, with socioeconomic factors such as insurance and income playing a dominant role. The disparities not only exact high human cost but also negatively impact the economics of health care. As we navigate the care of special patient populations such as these during a pandemic and design health care policies, social determinants of health are important factors to be kept in mind,” investigators of the study wrote.

The dataset included a total of 160,900 patients, of whom 56,102 were included in the analysis, and 50,543 were involved in the survival analysis. Patients had a median age of 69 years, and 55% were male. Most patients included in the study were non-Hispanic White, had insurance, resided in metropolitan areas, and were treated at either Comprehensive Community Cancer Centers or through Academic Programs. Additionally, most patients had a comorbidity score of 0.

To be eligible for treatment, patients were required to have been diagnosed with multiple myeloma between 2004 to 2016. Those who received hematopoietic stem cell transplant were excluded. Patients were only accepted if they had received systemic therapy as first line treatment. Patients were required to have active disease that was defined as undergoing treatment within 120 days of diagnosis. Patients were excluded if they were diagnosed at one center and received treatment at another.

Therapy enrollment rates were determined by receipt of systemic as the incident event of interest over time to the initiation of therapy; from there, investigators calculated the incidence rate ratios were assessed via Poisson regression analysis.

Investigators reported that the rate of enrollment to systemic therapy was 42.3 per 1000 person-days, and the median time to initiation of therapy was 17 days. Between 2004 to 2005 median overall survival was 28.5 months, which improved to 33.4 months in 2014 to 2015.

“By choosing to assess the enrollment rate to therapy, we were able to capture the impact of various factors on the timeline of diagnosis of the disease to initiation of myeloma-directed therapy. While this adds to the strength of the study, it should be noted that factors related to lack of receipt of therapy, which are important in determining outcomes, are not considered in the present study but have been evaluated previously,” the investigators concluded.

Reference

Jayakrishnan TT, Bakalov V, Chahine Z, Lister J, Wegner RE, Sadashiv S. Disparities in the enrollment to systemic therapy and survival for patients with multiple myeloma. Hematol Oncol Stem Cell Ther. 2021;14(3):218-230. doi:10.1016/j.hemonc.2020.09.005