Adherence to thalidomide in patients with multiple myeloma: A cross-sectional study in a Brazilian metropolis

Abstract

Purpose The treatment of multiple myeloma (MM) has advanced with the introduction of immunomodulators (IMiDS). Thalidomide is the IMiD available in Brazil with free access to MM patients. Adherence to treatment with IMiDs is essential for a successful therapy. The study proposed to describe adherence to thalidomide treatment in patients diagnosed with MM in onco-hematological outpatient clinics. Methods This is a cross-sectional study with patients over 18 years of age diagnosed with MM undergoing thalidomide treatment. Adherence was measured by the Proportion of Days Covered (PDC), which is an indirect method of measuring adherence that uses database-related medication dispensing information. Patients with PDC ≥90 were classified as adherent. The association between adherence and independent variables was assessed in univariate and multivariate analyses using logistic regression. Results A total of 65 patients with a median age of 62.6 years were identified. The median PDC was 93.7%. The frequency of adherence to thalidomide was 56.9%. Adherence to thalidomide showed a negative association with hospitalization in the last 12 months (OR = 0.202; 95% CI = 0.060–0.687) and with higher schooling (OR =0.161; 95% CI = 0.039–0.667) and a positive association with higher income (OR = 5.115; 95% CI = 1.363–19.190). Conclusion Most patients from onco-hematological outpatient clinics in a metropolitan region of southeastern Brazil showed high adherence to thalidomide, which was independently associated with higher income, hospitalization, and higher schooling. More studies are required to understand better the determinants of adherence to thalidomide in the country.

Validation of an Instrument for Measuring Adherence to Treatment With Immunomodulators in Patients With Multiple Myeloma

“…In Brazil, the thalidomide immunomodulator is available for free to patients in the public and private system and is currently produced by a single public laboratory (Silveira et al, 2021). Dispensing to patients is only made in pharmacies in the public health system accredited to assist patients using MM (BRASIL, 2011;Silveira et al, 2021). The easy access to the medication explains the greater use of this IMiD by the study patients.…”

“…Thalidomide is produced by a public foundation linked to the Brazilian Unified Health System (BUHS) and is dispensed free of charge only at public health system pharmacies accredited to care for MM patients. Lenalidomide has been registered in Brazil; however, it is not available to treatment free of charge in BUHS services (Silveira et al, 2021).…”

Quantificação de talidomida em plasma e em dispositivo de plasma seco por cromatografia líquida de alta eficiência acoplada a espectrometria de massas combinado com extração em fase sólida para monitoramento terapêutico

“…De fato, a baixa aderência ocorre em aproximadamente 60% dos pacientes tratados com talidomida para mieloma múltiplo, levando a uma alta taxa de hospitalização (Silveira et al, 2022). Além disso, essa baixa aderência ao medicamento ainda pode ser subestimada, uma vez que métodos indiretos são frequentemente aplicados para avaliação da aderência, e podem não detectar com precisão os pacientes não aderentes (Silveira et al, 2022;.…”

“…De fato, a baixa aderência ocorre em aproximadamente 60% dos pacientes tratados com talidomida para mieloma múltiplo, levando a uma alta taxa de hospitalização (Silveira et al, 2022). Além disso, essa baixa aderência ao medicamento ainda pode ser subestimada, uma vez que métodos indiretos são frequentemente aplicados para avaliação da aderência, e podem não detectar com precisão os pacientes não aderentes (Silveira et al, 2022;. Este fato foi recentemente demonstrado num trabalho publicado pelo nosso grupo, onde o único paciente sem resposta terapêutica à talidomida apresentou nível plasmático de talidomida não detectado, mostrando má aderência terapêutica .…”