This observational, retrospective cohort study using the Korean National Health Insurance (NHI) data will evaluate whether the risk of serious infections (SIs) in rheumatoid arthritis patients treated with tocilizumab is higher than in those with tumor necrosis factor inhibitors. We will compare incidence rates between two groups and estimate relative risks of SIs in tocilizumab users using the time-dependent Cox proportional hazard regression. Various covariates potentially related to RA severity and occurrence of infection will be assessed and used for adjustment.
The purpose of this study is to evaluate whether the risk of serious infections in rheumatoid arthritis patients with tocilizumab is higher than in those with tumor necrosis factor inhibitors using the nationwide real-world data.