Axial spondyloarthritis and inflammatory bowel disease: association between disease activity and endothelial dysfunction markers

OBJECTIVE: We aimed to assess patients with axial spondyloarthritis (axSpA) and inflammatory bowel disease (IBD) for disease activity and serum markers of endothelial dysfunction. METHODS: We studied 161 patients (123 males, 38 females) with axSpA: 153 with ankylosing spondylitis and 8 with non-radiographic axSpA, and 30 healthy controls (HC). We collected: age; sex; disease duration; extra-articular symptoms (IBD and acute anterior uveitis), comorbidities; human leukocyte antigen B27 status; and treatment. We measured serum interleukin (IL)-6, interleukin-18, IL-23, vascular endothelial growth factor (VEGF) epidermal growth factor (EGF), asymmetric dimethylarginine (ADMA), endothelin-1 (ET-1), and fetuin-A levels. RESULTS: IBD was diagnosed in 19 (11.8%) patients with axSpA. Compared to patients with axSpA without IBD, those with IBD had higher serum C-reactive protein (CRP) level (p = 0.05), erythrocyte sedimentation rate (ESR) (p = 0.005), and serum ET-1 levels (p = 0.01). In patients with axSpA and IBD, ET-1 levels correlated positively with CRP level (p = 0.006) and ESR (p = 0.02), and ADMA levels with visual analog scale scores (p = 0.01). Patients with axSpA and IBD had higher serum levels of IL-6 (p = 0.01), IL-18 (p = 0.005), and ADMA (p = 0.01) and lower serum levels of fetuin-A (p = 0.01) than did controls. CONCLUSIONS: Patients with axSpA and IBD had higher levels of disease activity, as assessed by ESR and CRP and ET-1 levels, than did patients with axSpA without IBD. Compared to HC, patients with axSpA and IBD had increased IL-18, ADMA levels and decreased fetuin-A level.