Clinical characteristics, laboratory measures, and quality of life as predictors of medication adherence in multiple myeloma

Abstract

Medication adherence in multiple myeloma (MM) is a key determinant of treatment outcomes, yet its relationship with patient-reported quality of life (QOL) remains insufficiently studied. We conducted a multi-center cross-sectional study across five West Bank hospitals (2018–2025), enrolling 250 adults with MM on active treatment. At enrollment, patients completed the EORTC QLQ-MY20 to assess disease-specific QOL, and one month later, adherence was evaluated using the Morisky Medication Adherence Scale-4 (MMAS-4). Most patients demonstrated medium (38.4%) or high (41.6%) adherence. Symptom burden was considerable, with lower back pain (76.4%), joint pain (69.2%), bone pain (63.6%), and constitutional symptoms (60.0%) reported frequently. Ordinal logistic regression revealed that higher scores in functional domains were strongly associated with better adherence, specifically in the Future Perspective (aCoeff = 1.044, p < 0.001) and Body Image (aCoeff = 0.757, p < 0.001) domains. In contrast, higher symptom burden predicted lower adherence: Side Effects (aCoeff = -1.134; p < 0.001) and Disease Symptoms (aCoeff = -1.020; p < 0.001). No significant associations were observed with most demographic, comorbidity, or laboratory variables. These findings demonstrate that QOL domains are independent predictors of adherence in MM. Routine QOL monitoring may help identify patients at risk of non-adherence and inform supportive interventions to sustain therapy and improve outcomes.