Immunomodulatory Agent Adherence Trajectories and Survival Among Older Patients With Multiple Myeloma

Immunomodulatory agents (IMiDs) are critical in treating multiple myeloma (MM). We aimed to identify patterns of adherence to IMiD treatment, patient characteristics associated with adherence, and the corresponding survival among Medicare beneficiaries with newly diagnosed MM.

Using group-based trajectory modeling, we identified distinct adherence groups among patients with MM in the SEER-Medicare database. Multinomial logistic regression models were used to identify factors associated with each adherence group. Cox proportional hazards regression models were sued to evaluate the impact of different adherence groups on survival.

We identified four distinct adherence groups among 4,452 patients with newly diagnosed MM between 2007 and 2019: (1) persistently-high (33.1%), (2) quick-decline-then-increase (17.5%), (3) moderate-decline (21.2%), and (4) quick-decline (28.2%). Factors related to poor-adherence groups included early treatment initiation years, patients with multiple comorbid conditions, hypercalcemia, renal failure, anemia, and bone disease and receiving a low-income subsidy. Patients age ≥85 years had higher odds of being in groups 3 and 4 than those age 66-69 years. Additionally, non-Hispanic Black patients were more likely to be in the quick-decline group than non-Hispanic White patients. Mortality was significantly associated with adherence. Patients in poor-adherence groups had a >20% increased mortality risk, compared with the persistently-high group.

Old age, low-income subsidy recipients, and those with high comorbidity burden are less likely to be adherent to the IMiD treatment, and their survival outcomes are inferior compared with those in the high adherence group. Targeted intervention to assist adherence to their IMiD treatment may improve the survival for these populations with newly diagnosed MM.