SAT0085 A MATRIX RISK MODEL FOR PREDICTING 5-YEAR RADIOGRAPHIC PROGRESSION IN A COHORT OF EARLY RHEUMATOID ARTHRITIS TREATED ACCORDING TO T2T STRATEGY
Authors: Anna Laura Fedele, Dario Bruno, Barbara Tolusso, Luca Petricca, Gianfranco Ferraccioli, Elisa Gremese
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background:</h3> In the treatment strategy of early rheumatoid arthritis (ERA) it is of pivotal importance to detect those patients who are at risk of radiographic progression (RP) in order to avoid decline in both functional capacity and quality of life. <h3>Objectives:</h3> To identify baseline predictive factors for 5-year RP in an observational cohort of ERA treated according to treat-to-target (T2T) strategy, and to create a matrix risk model including the strongest predictors. <h3>Methods:</h3> A total of 212 ERA patients with less than 12 months of disease duration (mean age 52.8±13.9 years, 75% female, 74.5% seropositive) and with available radiographs at 5 years of follow-up (FU), were enrolled in the study. ERA patients fulfilled the 2010 ACR criteria for RA and were followed according to the T2T strategy. At baseline, and every three months, the ACR/EULAR core data set variables were recorded. At baseline and every year, hand and foot radiographs were examined according to modified Total Sharp score (mTSS). At each visit, clinical improvement and remission were evaluated according to EULAR criteria. The achievement of Comprehensive Disease Control (CDC) (28-joint Disease Activity Score using C reactive protein &lt;2.6, Health Assessment Questionnaire &lt;0.5 and change from baseline in mTSS ≤0.5) was assessed every year of FU. <h3>Results:</h3> Fifty-six ERA patients (26.4%) had erosions on hand and foot radiographs performed at baseline. At 5 years of FU additional 56 subjects (26.4%) developed RP. ERA patients showing RP were in higher percentage ACPA positive (78.6%) and erosive at baseline (41.1%) compared to subjects not manifesting RP (65.4% ACPA positive, p=0.07; 21.2% erosive at baseline, <i>p=</i><i>0.004</i>, respectively). Moreover, radiographic progressors had a VERA disease (disease duration less than three months) with lower frequency (21.4%) compared to non progressors (34.6%, p=0.07). CDC was achieved at twelve months of FU more frequently by non progressors (52.6%) compared to patients developing RP (30.4%, <i>p=</i><i>0.004</i>). There were no differences regarding age, disease duration, BMI and smoking habit. Comparing the treatments between the two groups, we found similar frequencies of conventional and biotechnological drugs. In logistic regression analysis, the variables predictive of 5-year RP were ACPA positivity [OR (95%CI): 2.51 (1.12-5.63)], presence of erosions at baseline [OR (95%CI): 2.42 (1.16-5.06)] and not reaching CDC at the twelfth month of FU [OR (95%CI): 2.38 (1.18-4.76)]. Combining the coexistence of erosions at baseline and ACPA positivity (registered in 35 subjects, 16.5%o of the total cohort), the risk of RP increased [OR (95%CI): 3.50 (1.55-7.88)]. Dividing patients according to autoantibody positivity, the independent variables associated to RP were the presence of erosions at baseline [OR (95%CI): 2.91 (1.28-6.63)] and not having a VERA disease [OR (95%CI): 2.86 (1.06-7.69)]. In seronegative subjects predictive factors of RP were not identified. Using the parameters showing the strongest association with RP, three-parameter risk matrix was created, showing the proportion of ERA patients with RP in each box (Figure 1). The higher proportion of RP was showed in ACPA positive patients, regardless of all the other baseline predictors. <h3>Conclusion:</h3> In our cohort the predictive factors of 5-year RP were ACPA positivity, presence of erosions at baseline and not achieving CDC at 12<sup>th</sup> of FU. Although CDC is the advisable treatment goal, the radiological damage is not fully prevented in case of ACPA positivity. <h3>Disclosure of Interests:</h3> Anna Laura Fedele: None declared, Dario Bruno: None declared, Barbara Tolusso: None declared, Luca Petricca: None declared, Gianfranco Ferraccioli Speakers bureau: BMS, Roche, Elisa Gremese Consultant for: AbbVie, BMS, Celgene, Janssen, Lilly, MSD, Novartis, Sanofi, UCB, Roche, and Pfizer, Speakers bureau: BMS, Speakers bureau: Roche, Speakers bureau: AbbVie, BMS, Celgene, Janssen, Lilly, MSD, Novartis, Sanofi, UCB, Roche, and Pfizer