Influence of Depressive Symptoms on Disease Activity in Patients with Rheumatoid Arthritis: The Mediating Effect of Self-Efficacy

<i>Background and Objectives:</i> Rheumatoid arthritis (RA) is a lifelong autoimmune disease in which joint inflammation is caused by a dysfunctional immune system. Synchronous depressive symptoms have been identified as determinants of disease progression, especially disease activity as measured using the 28-joint Disease Activity Score (DAS28). Although growing evidence suggests the interplay between depression and DAS28 in RA, related findings remain inconsistent, implying that a pivotal underlying mechanism is overlooked. Hence, we aimed to examine whether self-efficacy, the belief in one's ability to manage health, could mediate the association between depressive symptoms and DAS28. <i>Materials and Methods:</i> Between January and October 2023, we carried out a cross-sectional survey to recruit patients with RA from a target hospital in Taiwan. Participants completed demographic and disease-related questionnaires, the Chinese version of the Arthritis Self-Efficacy Scale, and the Taiwanese Depression Questionnaire. Mediation analysis was performed using the Hayes PROCESS macro function on SPSS. <i>Results:</i> In 259 recruited persons with RA, depressive symptoms were found to negatively associate with self-efficacy, and self-efficacy negatively related to DAS28. Mediation analysis demonstrated that depressive symptoms affected DAS28 indirectly through self-efficacy (B = 0.022; 95% confidence interval: 0.015-0.031), accounting for 32.8% of the total impacts. <i>Conclusions:</i> Our findings suggest that the association between depressive symptoms and DAS28 may be mediated by individual self-efficacy. Interventions beyond the relief of depressive symptoms and that enhance the concept of self-efficacy should be emphasized while managing patients with RA.