Differences between females and males in axial spondyloarthritis: data from a real-life cross-sectional cohort.
Objective: Axial spondyloarthritis (axSpA) is a chronic inflammatory joint disease that usually presents with axial symptoms, but can also present with peripheral and extra-articular manifestations. It occurs equally in females and males. The diagnostic delay for axSpA is 5-7 years, and is significantly longer in females than in males. The aim of this study is to investigate the difference in disease characteristics between females and males with axSpA and to stratify this difference according to human leucocyte antigen (HLA)-B27 status. Method: Clinical characteristics, spondyloarthritis (SpA) features, disease activity parameters, X-rays of sacroiliac joints, and laboratory results were assessed in a real-life cross-sectional cohort of 389 patients with a clinical diagnosis of axial or peripheral SpA, and compared between genders. Results: Of 389 patients included, 313 had a clinical diagnosis of axSpA [females vs males, 131 (42%) vs 182 (58%), respectively]. Females had less radiographic axSpA according to the modified New York criteria (38.9% vs 63.7%, respectively), had a higher erythrocyte sedimentation rate [(median (interquartile range) 11 (5-23) vs 8 (3-16) mm/h), and reported higher disease activity by the Bath Ankylosing Spondylitis Disease Activity Index (mean ± sd 5.2 ± 2.1 vs 4.6 ± 2.2). No differences were found in clinical characteristics or SpA features, or when stratifying for HLA-B27 status. Conclusions: In this real-life cohort of patients with axSpA, although males more often had structural damage on X-rays, females had similar disease with regard to SpA features and at least equal disease activity parameters compared to males.