Undertreatment of Older Patients With Newly Diagnosed Multiple Myeloma in the Era of Novel Therapies

Abstract

Background: With the expanding armamentarium of therapeutic agents for multiple myeloma (MM), it is important to identify any undertreated patient populations to mitigate outcome disparities.

Materials and methods: We extracted the data for all plasma cell myeloma cases (International Classification of Disease for Oncology, third revision [ICD-O-3] code 9732) in the Surveillance, Epidemiology, End Results (SEER)-Medicare database from 2007 to 2011. The ICD-O-3 histologic code 9732 captures both active MM and smoldering/asymptomatic myeloma. We defined active MM as either claims indicating receipt of treatments approved for MM or ICD-9 codes for MM-defining clinical features, referred to as the CRAB criteria (calcium [elevated], renal failure, anemia, bone lesions). Multivariate logistic regression was performed to determine the variables that were independently associated with receipt of no treatment.

Results: Of the initial 4187 patients included in the present study, 373 had no claims indicating receipt of treatments approved for MM and had no ICD-9 codes associated with the CRAB criteria and were excluded from the analyses. Of the 3814 patients with active MM, 1445 (38%) did not have any claims confirming that they had received systemic treatment. Older age, poor performance indicators, comorbidities, African-American race, and lower socioeconomic status, including enrollment in Medicaid, were statistically significant factors associated with the receipt of no systemic treatment.

Conclusions: In the present retrospective study of data from the SEER-Medicare database, we found that age, health status, race, and socioeconomic status were associated with receipt of MM treatment. These factors have previously been linked to reduced usage of specific treatments for MM, such as stem cell transplantation. To the best of our knowledge, however, ours is the first study to show their association with the receipt of any MM therapy.

Keywords: Chemotherapy; Disparities; Elderly; Treatment.