title: The term 'non-radiographic axial spondyloarthritis' is much more important to classify than to diagnose patients with axial spondyloarthritis.
abstract: The term axial spondyloarthritis (axSpA) now is used frequently to describe patients with predominantly axial symptoms who fit into the spectrum of a well-recognised rheumatic disease that continues to be known as ankylosing spondylitis (AS). The 2009 Assessment of SpondyloArthritis international Society (ASAS) classification criteria, developed to identify patients with early or atypical disease which could not be classified by the 1984 modified New York (mNY) criteria for AS, have led to a differentiation between non-radiographic axial spondyloarthritis (nr-axSpA) and radiographic axSpA, which is largely synonymous with AS. The main reason to distinguish between these ends of the spectrum of axSpA was that tumor necrosis factor (TNF) inhibitors (TNFi) approved for AS could obtain additional labelling for nr-axSpA and be used to treat all patients manifesting clinical features of axSpA. These two terms are distinguished by the degree of 'radiographic sacroiliitis' assessed by conventional radiography, according to the 1984 mNY criteria for AS. Since this differentiation has been shown to be not very reliable, we argue that the terms nr-axSpA and AS should only be used for classification of patients with axSpA and not as separate diagnoses. Therefore, we propose that only the term axSpA be used to diagnose patients, unless there is a meaningful medical reason to differentiate nr-axSpA from AS. The available data justify performing randomised controlled trials designed to obtain regulatory approval for therapeutic agents in patients across the entire spectrum of axSpA.
authors.affiliation: Division of Arthritis & Rheumatic Diseases, Oregon Health & Science University, Portland, Oregon, USA.
authors.forename: Atul
authors.identifier: http://orcid.org/0000-0002-2130-1246
authors.initials: A
authors.lastname: Deodhar
authors.affiliation: Division of Immunology/Rheumatology, Stanford University School of Medicine, Palo Alto, California, USA.
authors.forename: Vibeke
authors.initials: V
authors.lastname: Strand
authors.affiliation: Division of Rheumatology, Department of Medicine, UMass Memorial Medical Center and University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Jonathan
authors.identifier: http://orcid.org/0000-0002-8970-4260
authors.initials: J
authors.lastname: Kay
authors.affiliation: Rheumazentrum Ruhrgebiet, Ruhr-University Bochum, Herne, Germany.
authors.forename: Juergen
authors.initials: J
authors.lastname: Braun
mesh_terms: D018501:Antirheumatic Agents / Q000627:therapeutic use; D003937:Diagnosis, Differential; D006801:Humans; D011859:Radiography; D025241:Spondylarthritis / Q000145:classification / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000188:drug therapy; D013167:Spondylitis, Ankylosing / Q000145:classification / Q000175:diagnosis / Q000188:drug therapy; D009626:Terminology as Topic; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors
chemical_list: D018501:Antirheumatic Agents; D014409:Tumor Necrosis Factor-alpha
keywords: Ankylosing Spondylitis; DMARDs (biologic); Epidemiology; Spondyloarthritis; Treatment