Serum Oxytocin Levels in Patients with Ankylosing Spondylitis and Non-Radiographic Axial Spondyloarthritis and their Association with Disease Activity

Abstract

ABSTRACT Objectives Spondyloarthritis refers to a group of chronic inflammatory diseases that particularly involve the sacroiliac joints and spine but may also have an influence on extra-articular involvement in some patients. Oxytocin is a peptide hormone released from the hypothalamus and stored in the pituitary gland. It is known to have anti-inflammatory effects. The aim of this study was to investigate the serum levels of oxytocin and their potential association with disease activity and spinal mobility in patients with ankylosing spondylitis (AS) and non-radiographic axial spondyloarthritis (nrAxSpA). Material and Methods Seventy-one patients with nrAxSpA, 38 patients with AS and 67 healthy control subjects were included in this study. Disease activity was assessed by the Bath Ankylosing Spondylitis Disease Activity Index, and spinal mobility by the Bath Ankylosing Spondylitis Metrologic Index. Laboratory examinations included complete blood count, ESR, CRP and oxytocin tests. Results There was no significant difference in serum levels of oxytocin among the 3 groups (p=0.973). However, serum levels of oxytocin correlated negatively with both ESR (r=− 0.359, p=0.027), CRP (r=− 0.316, p=0.056) and BASDAI scores (r=− 0,448, p=0.005) in patients with AS. On the other hand, serum levels of oxytocin had a negative correlation only with ESR in patients with nrAxSpA (r=− 0.321 p=0.009).Conclusion This study lays the foundation for further studies that may aim to investigate how addition of oxytocin to the treatment regimen impacts on disease activity in patients with AS who exhibit particularly low levels of oxytocin during the active disease period.