Impact of depression on adherence to lenalidomide plus low-dose dexamethasone in patients with relapsed or refractory...

While continued lenalidomide and low-dose dexamethasone (Rd) treatment could improve survival outcomes for multiple myeloma (MM), the association of depression on the adherence to Rd regimen in myeloma patients has never been studied even though depression is a common symptom among MM patients. This study aims to evaluate the impact of depression prior to Rd treatment on adherence to the treatment among patients with MM.

This multicenter cohort study was conducted from January 2015 to October 2018 at five tertiary hospitals in Korea. Patients who completed fewer than 4 cycles, 4-11 cycles, and more than 12 cycles were categorized as the poor adherence group (PAG), moderate adherence group (MAG), and good adherence group (GAG), respectively.

Among141 patients, 41.8% of them had depression before beginning Rd treatment and 46% of participants were in the GAG. Compared with patients in the GAG (30.3%), patients in the PAG were more likely to have depression at baseline (90.0%) and had the higher distress scores (6.35 vs. 4.28, P < 0.01). Presence of depression prior to Rd treatment was significantly associated with poor adherence (IRR = 6.67, 95% CI = 1.45, 30.61) after adjusting for age, sex, education, ECOG, ISS stage, number of previous treatments, and disease status prior to Rd treatment.

Patients with depression had a substantially high risk of poor adherence compared to patients without depression. Given that Rd treatment is mainly offered by outpatient clinics, active interventions to reduce depression should be considered for MM patients prior to Rd treatment.