Relationship between Depression and Medication Adherence in Patients with Multiple Sclerosis in Qazvin

Introduction and purpose: Multiple sclerosis (MS) is a chronic, autoimmune, inflammatory disease of the central nervous system that remains an incurable disease. Pharmacological treatment aims to minimize the debilitating symptoms, slow disease progression, and protect the quality of life. Medication adherence is one of the main success factors in the treatment of this chronic disease, which is influenced by various factors. This study aimed to determine the relationship between depression and medication adherence in patients with MS. Methods: This descriptive-analytical study was conducted on 200 patients with MS referred to Bu Ali Sina Hospital and Multiple Sclerosis Association in Qazvin City, Iran, in 2023. Patients were included in the study following convenience sampling. Data were collected by demographic checklist, Morisky Medication Adherence Scale (MMAS-8), and Beck Depression Inventory (BDI). Bivariate and multivariate logistic regression analyses were carried out using the SPSS-v25 software. Results: The mean and standard deviation of the scores of medication adherence and depression were 6.93±1.66 and 36.19±10.26, respectively. In 23.3% of the participants, the level of medication adherence was low, and depression was at moderate (30.5%) and severe levels (69.5%). In the multivariate regression analysis, with an increase in depression scores, the odds of non-adherence to treatment increased by 1.72 times, and patients suffering from more severe depression had lower medication adherence (P<0.0001). The odds of non-adherence to treatment in patients receiving oral medications compared to those receiving injectable medications was 2.144 times higher (P<0.039), and in unemployed patients compared to employed patients, it was 0.286 times higher (P<0.046). Conclusion: Depression has a significant negative impact on medication adherence in MS patients. Employment status and type of prescribed drugs are related to medication adherence in these patients. Therefore, the role of these factors should be taken into account when designing educational, caring, and supportive interventions.