Comparison of established and preliminarily proposed ASAS MRI working group cut-offs for inflammatory MRI lesions in the sacroiliac joints in radiographic and non-radiographic axial spondyloarthritis

• DOI: 10.1136/rmdopen-2023-003886
• Publication Date: 2024-09-04T04:45:23Z
• Authors: Xenofon Baraliakos; Pedro M Machado; Lars Bauer; Bengt Hoepken; Mindy Kim; Thomas Kumke; Rachel Tham; Martin Rudwaleit
• Keywords: Axial spondyloarthritis; Spondylitis

Background A consensus definition for active sacroiliitis by MRI, mentioned in the Assessment of SpondyloArthritis International Society (ASAS) classification criteria axial spondyloarthritis (axSpA), was published 2009 and included a qualitative quantitative MRI cut-off component. In 2021, updates to component were preliminarily proposed. This post hoc analysis part phase 3 open-label C-OPTIMISE study ( NCT02505542 ) explores differences applying preliminary 2021 inflammatory cut-offs on clinical outcomes axSpA patients treated with certolizumab pegol. Methods Baseline scans used classify 657 as MRI+ or MRI– according components lesions. Clinical outcomes, including ASAS ≥40% improvement (ASAS40), Ankylosing Spondylitis Disease Activity Score Bath Index, reported week 48. Results Across all analysed subgroups showed similar results. Notably, discordant group (2009 MRI+but group; 53/657 [8.1%]) close those seen either cut-offs, notably different from totality subgroups. Conclusion suggests that lesions may slightly increase specificity lesion definition. The effects updated need be assessed basis efficacy inclusion aspects structural changes. Trial registration number .