Patients with systemic lupus erythematosus (SLE) have an increased risk of developing severe infections compared with non-SLE cases. Moreover, 21% of the mortality in SLE is related to these infections. These were the main outcomes of a first large population-based incident SLE cohort study.
Previous studies investigating the infection risk in SLE have been prevalent cohort studies with small sample sizes. The current study is a large retrospective 1:5 matched incident cohort study based on 25 years of administrative data of 2,000,000 randomly selected Canadian citizens and 5,169 confirmed incident SLE cases (mean age 47, 90% women). Participants were matched for age and sex.
Outcome measures were: first severe infection (defined by the need for professional medical care), the number of severe infections, and infection-related death. The results demonstrated that SLE patients had an 82% increased risk of developing a severe infection compared with their matched non-SLE counterparts. Furthermore, SLE patients had twice as many severe infections and a 61% increased risk of infection-related death. Mr Kai Zhao (Simon Fraser University, Canada) argued that early SLE patients often have more disease activity and use more glucocorticoids.
According to Mr Zhao, these features could explain why these patients have an increased risk of severe infections. He suggested that a tailored treatment, including increased use of immunosuppressants, could provide a solution for this problem. In addition, further analysis of infection type (bacterial, viral) might give more insight into how to tackle severe infections in SLE in the future.
1. Zhao K, et al. Increased risk of severe infections and mortality in patients with newly diagnosed systemic lupus erythematosus: A population-based study. OP0043, EULAR 2021 Virtual Congress, 2-5 June.