What Is the Relationship Between Serum Copper–Zinc Superoxide Dismutase Levels and Disease Features in Patients with Rheumatoid Arthritis?

Copper–zinc superoxide dismutase (CuZnSOD) is an antioxidant enzyme that protects against oxidative damage. Oxidative stress plays a well-established role in the pathogenesis of rheumatoid arthritis (RA), being associated with elevated production of reactive oxygen and nitrogen species, along with enhanced lipid peroxidation, protein oxidation, and DNA damage. This study investigated the association between serum CuZnSOD levels and disease-related features in patients with RA, with a particular focus on cardiovascular (CV) comorbidity. A total of 150 patients with RA were enrolled in this cross-sectional study. After multivariable adjustment, CuZnSOD concentrations were not associated with most disease characteristics or activity measures, except for rheumatoid factor positivity, which was independently linked to higher CuZnSOD levels. Among CV parameters, CuZnSOD showed a positive correlation with the Systematic Coronary Risk Evaluation-2 CV risk calculator, both as a continuous and categorical variable, with the highest values observed in patients classified as very high risk. Besides, insulin levels were inversely related to CuZnSOD after adjustment. By combining multivariable analysis with broad phenotypic characterization, these findings support the hypothesis that CuZnSOD may reflect CV risk-related biology rather than disease activity in patients with RA. In conclusion, CuZnSOD serum levels in RA are linked to CV risk but not to joint disease activity. Antioxid. Redox Signal. 00, 000–000.