OP0149 RELIABILITY AND RESPONSIVENESS OF TWO OMERACT WHOLE-BODY MRI SCORES OF ENTHESEAL AND JOINT INFLAMMATION IN THE KNEE REGION IN SPONDYLOARTHRITIS
Authors: Wetterslev M. , Maksymowych W. P. , Lambert R. G. , Eshed I. , Juhl Pedersen S. , Stoenoiu M. , Krabbe S. , Bird P. , Foltz V. , Mathew A. J. , Gandjbakhch F. , Paschke J. , Carron P. , De Marco G. , Marzo-Ortega H. , Poulsen A. E. F. , Jaremko J. L. , Conaghan P. G. , Østergaard M. 
Published: May 2021

Background:Inflammation in peripheral joints and entheses is common in spondyloarthritis (SpA). Whole-body magnetic resonance imaging (WB-MRI) allows assessment of the overall inflammatory status of arthritis patients including joints and entheses. The OMERACT MRI Whole-body scoring system for Inflammation in Peripheral joints and Entheses (MRI-WIPE) [1] has been developed and validated for the entire body assessment, including the knee, but not separately validated for the knee joint region. Detailed MRI scoring systems exist for heels, hands and feet, but although knee arthritis is a key cause of functional impairment, no detailed scoring system has been validated for inflammatory arthritides. The Knee Inflammation MRI Scoring System (KIMRISS) [2] was developed and validated in osteoarthritis and demonstrated good reliability.Objectives:To perform region-based development of whole-body MRI through validation of two knee region scoring systems in SpA.Methods:Assessment of inflammation was performed in the knee region on sagittal WB-MRIs using 2 scoring systems, MRI-WIPE and KIMRISS (Figure 1), in 4 iterative multi-reader exercises. In the final exercise, images (psoriatic arthritis, axial and peripheral SpA) were obtained before and after TNF-inhibitor.Results:In the final exercise (exercise 4), reliability was mostly good for experienced readers with the overall highest interreader agreement in the previous exercise (exercise 3). Median pairwise single measure intraclass correlation coefficients for osteitis and synovitis/effusion for status/change were 0.71/0.48 (WIPE osteitis), 0.48/0.77 (WIPE synovitis/effusion), 0.59/0.91 (KIMRISS osteitis) and 0.92/0.97 (KIMRISS synovitis/effusion) (Table 1). Wilcoxon signed-rank test showed significant change in synovitis/effusion for both methods and they correlated significantly regarding status in osteitis (0.92, p<0.001) and synovitis/effusion (0.89, p=0.001) and change in synovitis/effusion (0.89, p<0.001). Standardized response mean was 0.74 (WIPE synovitis/effusion) and 0.78 (KIMRISS synovitis/effusion).Table 1.MRI-WIPE knee and KIMRISS interreader reliability for OMERACT exercises 3 and 4MRI-WIPE KneeKIMRISSOsteitisSynovitis/effusionOsteitisSynovitis/effusionVariablesNo. patientsType of scoreMean scoreICCMean scoreICCMean scoreICCMean scoreICCExercise 39 readers11Status3.6 (0-16)0.57 (-0.06-0.98)1.8 (0-4)0.47 (0.05-0.85)32.3 (1-224)0.87 (0.66-0.99)29.9 (11-60)0.34 (-0.62-0.87)11Change1.1 (-2-6)0.53 (0.03-0.90)0 (-2-1)0.32 (-0.13-0.76)27.7 (-9-131)0.58 (-0.30-0.96)-1.6 (-33-11)0.48 (-0.32-0.95)Exercise 33 readers11Status3.1 (0-16)0.83 (0.71-0.97)2.5 (0-5)0.59 (0.51-0.71)34.4 (0-233)0.89 (0.83-0.99)36.5 (16-78)0.59 (0.08-0.86)11Change0.9 (-3-6)0.72 (0.57-0.83)0 (-2-1)0.63 (0.49-0.76)19.3 (-23-86)0.46 (0.18-0.83)-1.8 (-45-17)0.89 (0.82-0.95)Exercise 49 readers10Change-0.25 (-4-5)0.38 (-0.35-0.94)-1.0 (-3-1)0.30 (-0.43-0.89)-0.45 (-37-65)0.26 (-0.86-0.97)-14.7 (-48-0.20)0.48 (-0.39-0.99)20Status2.9 (0-7)0.50 (-0.01-0.84)2.1 (0-4)0.44 (-0.21-0.79)15.2 (0-66)0.35 (-0.04-0.89)55.6 (1-122)0.54 (0.01-0.96)Exercise 43 readers10Change0.2 (-2-6)0.48 (0.16-0.66)-1.4 (-5-0)0.77 (0.70-0.82)5.8 (-27-111)0.92 (0.90-0.94)-20.7 (-65-28)0.97 (0.96-0.98)20Status2.3 (0-6)0.71 (0.60-0.80)2.7 (0-5)0.48 (0.42-0.57)11.4 (0-36)0.59 (0.39-0.71)69.4 (1-153)0.91 (0.87-0.93)Sum scores are mean (range) of the patients scores. ICC values are mean (range). ICC is 2-way mixed model, single measure, by absolute agreement.Conclusion:MRI-WIPE and KIMRISS may both be useful as part of modular whole-body evaluation in clinical studies.References:[1]Krabbe S et al. J Rheum. 2019;46(9):1215-21[2]Jaremko JL et al. RMD Open. 2017;3(1):e000355Acknowledgements:We thank CARE Aarthritis Limited (carearthritis.com) for help with setting up the web-based scoring interface, the scoring exercises, and the web-based meetings. We thank all who participated in the SIG (Special Interest Group) virtual OMERACT meeting 29 October 2020. HMO, GDM and PGC are supported in part by the National Institute for Health Research (NIHR) Leeds Biomedical Research Centre, United Kingdom. The views expressed in this study are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health.Disclosure of Interests:Marie Wetterslev: None declared, Walter P Maksymowych Speakers bureau: AbbVie, Janssen, Novartis, Pfizer and UCB, Consultant of: AbbVie, Boehringer Ingelheim, Celgene, Eli Lilly, Galapagos, Janssen, Novartis, Pfizer and UCB, Grant/research support from: AbbVie, Novartis, Pfizer and UCB, Robert G Lambert Consultant of: Parexel and Pfizer, Iris Eshed: None declared, Susanne Juhl Pedersen Speakers bureau: MSD, Pfizer, AbbVie, Novartis and UCB, Consultant of: AbbVie and Novartis, Grant/research support from: AbbVie, MSD, and Novartis, Maria Stoenoiu: None declared, Simon Krabbe: None declared, Paul Bird Speakers bureau: Janssen, Abbvie, UCB, Celgene, BMS, Novartis, Pfizer, Gilead, Eli-Lilly, Consultant of: Janssen, Abbvie, UCB, Celgene, BMS, Novartis, Pfizer, Gilead, Eli-Lilly, Violaine Foltz: None declared, Ashish Jacob Mathew: None declared, Frederique Gandjbakhch: None declared, Joel Paschke: None declared, Philippe Carron Speakers bureau: Pfizer, MSD, Novartis, BMS, AbbVie, UCB, Eli Lilly, Gilead and Celgene, Consultant of: Pfizer, MSD, Novartis, BMS, AbbVie, UCB, Eli Lilly, Gilead and Celgene, Grant/research support from: UCB, MSD and Pfizer, Gabriele De Marco: None declared, Helena Marzo-Ortega Speakers bureau: AbbVie, Celgene, Janssen, Lilly, Novartis, Pfizer, Takeda and UCB, Grant/research support from: Janssen and Novartis, Anna Enevold Fløistrup Poulsen: None declared, Jacob L Jaremko: None declared, Philip G Conaghan Speakers bureau: AbbVie, AstraZeneca, BMS, Eli Lilly, EMD Serono, Flexion Therapeutics, Galapagos, Gilead, Novartis, Pfizer and Stryker, Consultant of: AbbVie, AstraZeneca, BMS, Eli Lilly, EMD Serono, Flexion Therapeutics, Galapagos, Gilead, Novartis, Pfizer and Stryker, Mikkel Østergaard Speakers bureau: Abbvie, BMS, Boehringer-Ingelheim, Celgene, Eli-Lilly, Hospira, Janssen, Merck, Novartis, Pfizer, Regeneron, Roche, Sandoz, Sanofi and UCB, Consultant of: Abbvie, BMS, Boehringer-Ingelheim, Celgene, Eli-Lilly, Hospira, Janssen, Merck, Novartis, Pfizer, Regeneron, Roche, Sandoz, Sanofi and UCB, Grant/research support from: Abbvie, BMS, Boehringer-Ingelheim, Celgene, Eli-Lilly, Hospira, Janssen, Merck, Novartis, Pfizer, Regeneron, Roche, Sandoz, Sanofi and UCB