SAT0240 DEVELOPMENT AND PRELIMINARY VALIDATION OF THE BEHÇET’S SYNDROME OVERALL DAMAGE INDEX (BODI)

Background Irreversible organ damage is considered a core outcome by the OMERACT working group. However, no specific tools are currently available to detect and measure damage accrual in Behcet’s syndrome (BS). Objectives To develop and preliminarily validate the Behcet’s syndrome Overall Damage Index (BODI). NCT03803462. Methods A preliminary version of the instrument (p-BODI) was developed by reviewing pre-existing tools [e.g. Vasculitis damage index (VDI)] and through an extensive literature review. p-BODI was then reviewed and implemented by a multi-rounds Delphi process, involving an international and multidisciplinary (5 rheumatologists, 4 internist, 1 ophthalmologist, 1 neurologist) panel of experts in BS management and a patients’ delegate. A group of clinicians (CG), not involved in the BODI development, was asked to independently score a set of clinical vignettes, in order to test the instrument reliability, after a training process consisting of a user manual and a video-tutorial. Then, Cohen’s K and Intra-class correlation coefficient (ICC) between assessors and gold standard were calculated. Afterwards, BODI validation was conducted according to the OMERACT Filter 2.0 in a multicenter BS cohort. Results Starting from a list of 120 candidate items, the final version of BODI consisted of 4 overarching principles, 30 items and 12 sub-items (each of them scores one point) grouped in 8 domains (figure). In terms of reliability, the mean K coefficient was 0.84 (95%CI 0.78 to 0.90) and the ICC was 0.88 (95%CI 0.80-0.95). Validation cohort consisted of 228 BS patients (49.1% males), with a median (IQR) age and disease duration of 46.9 (35.5-55.0) and 11.7 (5.8-20.7) years, respectively. Overall, prevalence of any BODI damage (BODI ≥1) was 56.1% with a median score of 1.0 (0-2.0). In regard of construct validity, BODI score significantly correlated with VDI (Spearman’s rho 0.693, p Full agreement among the CG was reached in judging BODI as a credible, comprehensive, easy to use, timesaving and acceptable instrument. Conclusion BODI is the first tool specifically developed to assess damage in BS. Preliminary data encourage further validation of BODI in more extended and multi-ethnic BS cohorts before being applied in clinical practice and as a therapeutic outcome. Disclosure of Interests Matteo Piga: None declared, Alberto Floris: None declared, Gerard Espinosa: None declared, Nikolaos Kougkas: None declared, Andrea Lo Monaco: None declared, Giuseppe Lopalco Speakers bureau: SOBI, BMS, Ida Orlando: None declared, Vittorio Pirani: None declared, Ernestina Santos: None declared, Luisa Serpa Pinto: None declared, George Bertsias: None declared, Luca Cantarini: None declared, Alberto Cauli: None declared, Ricard Cervera: None declared, Joao Correia: None declared, Marcello Govoni: None declared, Florenzo Iannone Consultant for: F Iannone has received consultancy fees and/or speaker honoraria from Pfizer, AbbVie, MSD, BMS, Novartis, Lilly, UCB outside this work, Speakers bureau: F Iannone has received consultancy fees and/or speaker honoraria from Pfizer, AbbVie, MSD, BMS, Novartis, Lilly, UCB outside this work, Ana Martins da Silva: None declared, Piergiorgio Neri: None declared, Carlos Vasconcelos: None declared, Monica Muntoni: None declared, Alessandro Mathieu: None declared