Immunomodulator adherence in multiple myeloma patients with lower socioeconomic status: a retrospective study

Poor adherence to oral chemotherapy adversely impacts clinical outcomes and escalates overall healthcare costs. Despite barriers to medication adherence, a significant gap remains in assessing adherence to oral chemotherapy among multiple myeloma (MM) patients with lower socioeconomic status. Hence, our study aims to evaluate immunomodulator adherence in MM patients at a county hospital, primarily serving underrepresented and indigent individuals with low socioeconomic status across the greater Houston area.

Inclusion criteria composed of patients diagnosed with MM, aged at least 18 years, and treated with lenalidomide or pomalidomide—two widely used immunomodulators—for a minimum of 2 months or having two or more records of dispensation between May 2019 and May 2021. Adherence was gauged using an adjusted version of the medication possession ratio (MPR).

Sixty-two patients were enrolled, yielding a mean MPR value of 88% (SD, ± 18.9). Of these, 43 patients (69.3%) demonstrated adherence with an MPR of ≥ 0.90. A significant difference was found in treatment duration between the adherent (mean 8.8 months; SD, ± 7.2) and non-adherent (mean 13.4 months; SD, ± 7.9) groups (p = 0.027). Notably, race/ethnicity demonstrated a significant difference (p = 0.048), driven by disparities in African American and Hispanic representation across adherence levels.

In summary, our findings highlight race and treatment duration to be predictors of immunomodulator adherence among MM patients with lower socioeconomic status. Further research is imperative to devise and test innovative interventions aimed at enhancing medication adherence, thereby contributing to improved survival and healthcare quality in this population.