Association between antinuclear antibodies, oxidative stress index, and immune markers in systemic lupus erythematosus

Autoimmune disorders have been reported with a high incidence among the Iraqi population in the past year, including systemic lupus erythematosus (SLE). This study was designed to assess the association between oxidative stress index and antinuclear antibodies, as well as their relationship with clinical features in SLE cases. A case-control study was conducted involving 50 patients with SLE and 50 healthy individuals. Clinical features and oxidative stress markers—including total oxidant status (TOS), total antioxidant capacity (TAC), oxidative stress index (OSI), malondialdehyde (MDA), and antinuclear antibody (ANA)—were assessed. Data were analyzed using statistical tests with a significance level of p < 0.05. Results SLE patients exhibited significantly higher levels of total oxidant status (TOS), oxidative stress index (OSI), malondialdehyde (MDA), and nitric oxide (NO) compared with controls (p < 0.05), while total antioxidant capacity (TAC) was significantly lower. Age and BMI were comparable between groups. Oxidative stress parameters were largely similar across clinical subgroups, except for higher MDA levels in patients without fever. Correlation analysis demonstrated a strong association between OSI, TOS, and TAC. Regression models identified TOS and TAC as independent predictors of OSI, whereas antinuclear antibody (ANA) was not independently associated with oxidative markers. Systemic lupus erythematosus (SLE) is characterized by a significant oxidative imbalance that occurs independently of demographic factors, alongside elevated autoimmune activity. Oxidative stress appears to be a core feature of the disease, operating partly independently of immune markers.