POS0963 HOW IS EARLY SPONDYLOARTHRITIS DEFINED IN THE LITERATURE? RESULTS FROM A SYSTEMATIC REVIEW

BackgroundThe term “early spondyloarthritis (SpA)” has been frequently used to refer to the first phase of the disease, however, no standardized definition on “early” has been established. The ASAS-SPEAR (SPondyloarthritis EARly definition) project aims at developing a consensual definition on what is meant by “early SpA”. In order to inform the ASAS-SPEAR working group, it is highly relevant to assess the current meaning of “early SpA” in the literature.ObjectivesTo identify all possible definitions of “early SpA” employed in the literature, including “early axial SpA (axSpA)” and “early peripheral SpA (pSpA)”.MethodsA systematic literature review was conducted in Medline, EMBASE and the Cochrane Library (through April 28th, 2021). The eligibility criteria were studies with any design, in adults that included any mention of “early SpA” or its subtypes in the title or abstract. Two reviewers independently identified eligible studies and extracted data, including the literal definition of early SpA used in each of them. The proportion of studies reporting a definition was calculated, and the different definitions were assessed, including the core of the definition: whether they were based on symptom duration, disease duration, radiographic damage, a combination of them or any other aspects, and their boundaries.ResultsOut of 9,651 titles identified, 355 publications reporting data from 186 studies were included (291 full papers, 64 conference abstracts). Among them, 217 (61%) were cohort studies, 72 (20%) were reviews and 46 (13%) were clinical trials. Over time, an increasing number of publications on early SpA were identified: Table 1.Top 3 candidate definitions for “early SpA” and subtypesCore of the definitionNumber of studies, n (%)SpA (n= 35)nr-axSpA10 (29%)< 2 years duration10 (29%)< 1 year duration6 (17%)AxSpA (n=38)< 5 years duration12 (34%)< 3 years duration9 (24%)nr-axSpA duration8 (21%)AS/r-axSpA (n=38)9 (24%)nr-axSpA7 (18%)< 2 years duration6 (16%)nr-axSpA (n=4)nr-axSpA2 (50%)< 1 year & nr-axSpA1 (25%)< 5 years & nr-axSpA1 (25%)pSpA (n=1)< 12 weeks duration1 (100%)“Duration” refers to symptom duration or disease duration.Figure 1.Number of studies stratified by the core of the definition.ConclusionOver time, the term “early SpA” and its subtypes are increasingly used. Despite addressing early SpA, more than one third of the studies did not include a clear definition of the term. The studies reporting a definition of early SpA showed a large heterogeneity, with two out of three of them based on the duration of symptoms or disease. These results emphasize the need for a standardised definition of early SpA.AcknowledgementsThe Assessment of Spondyloarthritis international Society (ASAS) supported Diego Benavent financially for this work.Disclosure of InterestsDiego Benavent Speakers bureau: Jannsen, Roche, Grant/research support from: Novartis., Dafne Capelusnik Speakers bureau: Bristol Myers Squibb, Pfizer, Grant/research support from: Pfizer, Désirée van der Heijde Consultant of: AbbVie, Bayer, BMS, Cyxone, Eisai, Galapagos, Gilead, Glaxo-Smith-Kline, Janssen, Lilly, Novartis, Pfizer, UCB Pharma., Employee of: Director of Imaging Rheumatology bv., Robert B.M. Landewé Consultant of: AbbVie, BMS, Galapagos, Gilead, GSK, Janssen, Lilly, Novartis, Pfizer, UCB, Denis Poddubnyy Speakers bureau: AbbVie, Bristol-Myers Squibb, Eli Lilly, MSD, Novartis, Pfizer, and UCB, Consultant of: AbbVie, Biocad, Eli Lilly, Gilead, GlaxoSmithKline, Janssen, MSD, Novartis, Pfizer, Samsung Bioepis, and UCB, Grant/research support from: AbbVie, Eli Lilly, MSD, Novartis, and Pfizer, Astrid van Tubergen Consultant of: Novartis, Galapagos, Grant/research support from: Pfizer, UCB, Novartis, Louise Falzon: None declared, Sofia Ramiro Speakers bureau: Eli Lilly, MSD, Novartis, UCB, Consultant of: AbbVie, Eli Lilly, MSD, Novartis, Pfizer, UCB, Sanofi, Grant/research support from: AbbVie, Galapagos, Novartis, Pfizer, UCB, Victoria Navarro-Compán Speakers bureau: AbbVie, Eli Lilly, Janssen, MSD, Novartis, Pfizer, UCB Pharma, Consultant of: AbbVie, Eli Lilly, MSD, Novartis, Pfizer, UCB Pharma, Grant/research support from: Abbvie and Novartis