Reciprocal associations between beliefs about medicines, health locus of control and adherence to immunosuppressive medication in allogeneic hematopoietic cell transplant patients: Findings from the ADE-TRAM study

Abstract

Purpose: Patients undergoing allogenic hematopoietic stem cell transplantation (allo-HSCT) are required to strictly adhere to immunosuppressive medications to avoid rejection and infective complications. Since medication adherence is among the most important modifiable behaviors to achieve better outcomes, the aims of this study were to measure the baseline and longitudinal trends of medication adherence and investigate the psychological factors associated with medication adherence in allo-HSCT patients.

Methods: This was a single-center, longitudinal study of patients who underwent allo-HSCT to treat hematological malignancies at the University hospital of Florence (Italy). Adherence was measured with the Immunosuppressive Medication Self-Management Scale; psychological factors (i.e., beliefs about medicines and health locus of control) were measured with the Beliefs About Medicines Questionnaire and Multidimensional Health locus of Control Scale. Data were collected 1, 3, 6 and 12 months after discharge. A mixed effects model was performed after adjusting for demographic characteristics.

Results: 50 adult patients were included in this study. Adherence to immunosuppressant was optimal and increased significantly 3 months after bone marrow transplantation (B = 0.23, p = 0.041). Patients with lower concerns about immunosuppressive medications were more likely to be adherent (B = 0.02, p = 0.040), while those having beliefs that their disease was due to external factors were less likely to be adherent (B = -0.02, p = 0.026) than their counterparts.

Conclusions: These results underline the importance of psychological factors in affecting adherence to immunosuppressants of allo-HSCT patients. Healthcare providers and researchers should target medication beliefs and reorient locus of control with appropriate interventions, in order to improve adherence.

Keywords: Health belief model; Hematopoietic stem cell transplantation; Immunosuppressive therapy; Internal-external control; Longitudinal studies; Medication adherence; Self report.