LAUSR

Background: Disease activity assessment is crucial in defining the appropriate therapy and to monitor the efficacy of treatment in systemic sclerosis. Objectives: We aimed to test the performance of the ’old’ European Scleroderma Trials and Research Group (EUSTAR) Activity Index (old-AI) (1), the ’new’ EUSTAR activity index (new-AI) (2), and the scleroderma activity index derived from the old-AI (Pecs-AI) (3). We compared the three indices to the disease activity based on the physician’s global assessment (PGA). We also assessed the correlations with the change in modified Rodnan Skin Score (MRSS), FVC and arthritis after one year follow-up. Methods: We evaluated 77 patients (50 diffuse /dcSSc/ and 27 limited cutaneous SSc /lcSSc/ patients) from a single tertiary clinical center. Cohort enrichment was performed to increase the number of patients with early disease and dcSSc. Seventy-two patients were re-evaluated after one year. Nine patients had overlap syndromes: rheumatoid arthritis (n=3), Sjogren syndrome (n=2), polymyositis (n=2), and mixed connective tissue disease (n=2). The overall disease activity was evaluated using both composite indices (old-AI, Pecs-AI, new-AI) and the PGA of disease activity, based on the blinded evaluation of a single physician (LV). In addition to the minimal essential data from the EUSTAR database we also performed detailed assessment of the musculoskeletal involvement evaluating measures of hand function, DAS28 scores, and the Clinical Disease Activity Index (CDAI) (4). Results: Three times more patients with active disease were identified by the new-AI compared to the old-AI at baseline investigation (n=37, 48.7%, vs. n=11, 14.3%). Two patients (18%) with active disease based on the old-AI were missed by the new-AI. Pecs-AI index identified 15 patients (19.5%) with active disease (cut-off >2.75 points). Active disease was equally frequent in dcSSc and lcSSc patients based on old-AI, but was more frequent in dcSSc patients based on the new-AI in the whole cohort, and also after excluding overlap cases. Patients with active disease based on the old-AI had more frequently rheumatoid factor (6/9, vs. 12/45, p=0.047), and DLCO CDAI correlated significantly with the old-AI (rho: 0.345, and rho: 0.283, respectively, p Conclusion: The two validated disease activity indices indentify different patient groups. Joint involvement is potentially underrepresented in the new EUSTAR activity index. Active disease is also present in lcSSc and should be assessed regularly in these patients. References: [1]Valentini G, et al. Ann Rheum Dis 2003; 62: 901-3. [2]Valentini G, et al. Ann Rheum Dis 2017;76:270–276. [3]Minier T, et al. Rheumatology (Oxford) 2010;49(6):1133-45. [4]Lorand V, et al. Rheumatology (Oxford). 2016;55(10):1849-58. Acknowledgments: This work was supported by the EU Seventh Framework Program [FP7/2007-2013] under Grant Agreement n° 305495 (DeSScipher), by the Hungarian Scientific Research Fund (contract n°: 112939), and the EU under the Grant Agreement n° PEPSYS GINOP-232-15-2016-00050. Disclosure of Interests: Tunde Minier Speakers bureau: Actelion, Abbvie, MSD, Pfizer, Lilly, Roche, Veronika Lorand: None declared, Zsofia Balint: None declared, Dalma Komjati: None declared, Gabriella Nagy Speakers bureau: MSD, Antonietta Kovacs: None declared, Orsolya Koncz: None declared, Cecilia Varju Consultant of: Boehringer Ingelheim RCV GmbH & Co KG, Speakers bureau: Lilly, Laszlo Czirjak Consultant of: Actelion, BI, Roche-Genentech, Lilly, Medac, Novartis, Pfizer, Bayer AG, Gabor Kumanovics Consultant of: Boehringer, Teva, Speakers bureau: Roche, Lilly, Novartis, Balazs Nemeth: None declared