Tocilizumab Reduces Depression Risk in Rheumatoid Arthritis Patients: A Systematic Review and Meta-Analysis

Depression is a possible cause of the increased mental health risks associated with rheumatoid arthritis (RA), including depression-related complications. Biological disease-modifying antirheumatic drug (bDMARDs) therapies have emerged as innovative anti-inflammatory drugs with positive effects on mental well-being. Tocilizumab is a bDMARDs commonly used to treat RA and its influence on depression needs to be studied. It targets interleukin-6 (IL-6) receptors, reducing inflammation, which may also alleviate depressive symptoms due to the role of inflammation in the pathophysiology of depression. Thus, its influence on depression needs to be studied. To assess the strength of the association between exposure to tocilizumab and the rate of development of depression in patients with RA and to evaluate tocilizumab as an exposure and depression as an outcome in these patients, a search was conducted in the MEDLINE, PreMEDLINE, Cochrane, and Scopus databases from January 1980 to April 2024. Inclusion criteria were studies that diagnosed RA according to the latest American College of Rheumatology/European League Against Rheumatism guidelines or a rheumatologist and provided information on tocilizumab exposure and diagnosed depression as an outcome. The present meta-analysis was conducted following the guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement. These studies were assessed for eligibility by the author and an independent assessor. To summarize the findings, the meta-analysis combined the relative risk estimates from each study with raw data counts. Twelve studies in the meta-analysis fulfilled the inclusion criteria. Tocilizumab monotherapy exhibited a promising beneficial effect on the risk of depression, indicated by the decreased risk in RA patients (Relative risk 0.68, 95% CI 0.20, 2.31). Patients with RA on tocilizumab treatment had a lower risk of developing depression compared to those unexposed to tocilizumab treatment. Therefore, future longitudinal studies are needed to confirm the beneficial effect of tocilizumab on depression in the RA population.