Risk of Cytomegalovirus Viremia in Systemic Lupus Erythematosus Compared with Other Systemic Autoimmune Rheumatic Diseases: A Multicenter Retrospective Cohort Study

Risk of Cytomegalovirus Viremia in Systemic Lupus Erythematosus Compared with Other Systemic Autoimmune Rheumatic Diseases: A Multicenter Retrospective Cohort Study

Objectives: We aimed to compare the risk of cytomegalovirus (CMV) viremia in patients with systemic lupus erythematosus (SLE) versus those with other systemic autoimmune rheumatic diseases (SARDs), and to identify independent clinical predictors associated with CMV viremia. Methods: This retrospective cohort study utilized data from the Chang Gung Research Database between 2005 and 2020. Patients with SLE and other SARDs were extracted and matched using a propensity score based on gender, age, diagnostic year, and comorbidities. The risk of CMV viremia was compared between the two groups. Cox proportional hazards regression analysis was performed to identify risk factors for CMV viremia. Results: After propensity score matching, 2692 patients were included in each group. The risk of CMV viremia was significantly higher in the SLE group than in the other SARDs group (adjusted hazard ratio 3.08, 95% confidence interval 1.04–9.14, P = 0.04). Multivariable Cox regression analysis demonstrated that decreased immunoglobulin M (IgM) and complement 3 (C3) levels were independently associated with an increased risk of CMV viremia among SLE patients. Conclusions: Compared with other SARD patients, SLE patients have a significantly higher risk of CMV viremia, and low IgM and C3 levels independently predict CMV viremia, supporting risk stratification and surveillance in high‑risk SLE subgroups.