Elevated oxidative stress markers in patients with ankylosing spondylitis: A case-control study.

BACKGROUND

Ankylosing spondylitis (AS) is a chronic inflammatory musculoskeletal disease with an unclear pathogenesis. Oxidative stress (OS) is currently becoming an area of interest in AS pathogenesis and progression.

OBJECTIVE

The aim of this study was to evaluate serum oxidative and anti-oxidative status in patients with AS and to assess the relationships between OS markers and disease indices.

PATIENTS AND

METHODS

Forty-four AS patients (mean age: 44.9±14.12 years, sex-ratio M/F: 2.14) and 46 healthy controls (mean age: 44.62±10.74 years, sex-ratio M/F: 2.28) with no known diseases were included in the study. Oxidant markers - advanced oxidative protein products (AOPP) and malondialdehyde (MDA) - and anti-oxidant molecules - catalase (CAT), glutathione peroxidase (GPx) and reduced gluthatione (GSH) - were measured. The Bath ankylosing spondylitis disease activity index (BASDAI) and the Bath ankylosing spondylitis functional index (BASFI) were calculated.

RESULTS

In AS patients, mean disease duration was 21.11 months [range: 2-54] and the mean BASDAI and BASFI scores were 4.52±1.45 and 4.64±2.52, respectively. No differences in term of age, sex, body mass index, blood pressure, glucose, lipid profile, uric acid, total bilirubin and homocystein level were observed. The levels of oxidant markers (AOPP and MDA) were significantly higher (p<10-6) and the levels of anti-oxidant markers (CAT, GPx and GSH) were significantly lower (p<10-6) in AS patients than those in healthy control subjects. Correlation analysis showed a significant positive correlation between AOPP levels and BASDAI score (p=0.001) and BASFI score (p=0.006) and a significant negative correlation between GPx activity and BASDAI score (p=0.001) and BASFI score (p=0.01).

CONCLUSION

This study demonstrates an oxidative stress condition characterized by increased oxidant markers and decreased antioxidant capacity in AS patients compared to controls, suggesting that OS may play a crucial role in the pathogenesis and progression of the disease.