Aim: To evaluate the relationship between serum oxidant-antioxidant levels and the duration of the illness, disease activity and treatment modality in patients with axial spondyloarthritis (axSpA).

Material and Methods: Fourty two patients with axSpA and 20 healthy controls were included in this cross-sectional study. To evaluate the serum oxidant-antioxidant levels of the patients, total antioxidant status (TAS), total oxidant status (TOS) and oxidative stress index (OSI) levels were measured. Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), Bath Ankylosing Spondylitis Metrology Index (BASMI), ASQoL (Ankylosing Spondylitis Quality of Life Index) scores, chest expansion, and number of enthesitis were recorded.

Results: No difference was observed in terms of demographic characteristics, laboratory findings, serum TOS and TAS levels between the patient and control groups (p> 0.05). The TOS and TAS concentrations did not differ between patients treated with biological agents and those treated with conventional agents; and did not differ between cases of active (BASDAI ≥4) and inactive axSpA (p> 0.05). Only the TAS levels were found to be higher in patients with axSpA whose disease duration is >1 year than patients with disease duration ≤1 year (p <0.05); but there was no significant difference between the TOS and OSI levels in terms of disease duration. No correlation was found between laboratory and clinic parameters.

Conclusion: Serum oxidant and antioxidant levels may not be the guiding parameters in the treatment and follow-up of axSpA disease.