FRI0674 THE ASSOCIATION BETWEEN JOINT EROSIONS PLUS AUTOANTIBODY POSITIVITY AT INITIATION OF METHOTREXATE OR BIOLOGIC THERAPY FOR RHEUMATOID ARTHRITIS AND DISEASE ACTIVITY AND DISABILITY OVER ONE YEAR
Authors: James Gwinnutt, Kimme Hyrich, Mark Lunt, Darren Plant, Nisha Nair, Anne Barton, Suzanne Verstappen
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> Joint erosions and autoantibody positivity (rheumatoid factor [RF], anti-cyclic citrullinated peptide antibody [anti-CCP]) predict poor outcomes in patients with rheumatoid arthritis (RA). There are limited data on the combination of these factors and clinical and patient reported outcomes over time. <h3>Objectives</h3> To compare the disease activity and disability over 1 year of those with poor prognostic factors at treatment initiation (methotrexate [MTX] or biologics) to those without. <h3>Methods</h3> Patients were recruited to 1 of 2 UK-based multi-centre prospective cohort studies: MTX-starters: Rheumatoid Arthritis Medication Study (RAMS); biologic-starters: Biologics in Rheumatoid Arthritis Genetics and Genomics Study Syndicate (BRAGGSS). Anti-CCP (Axis-Shield Anti-CCP test; U/ml; anti-CCP titre &gt;5 U/ml = anti-CCP+)/RF (Beckman Coulter AU5400, RF latex assay; IU/ml; RF titre &gt;14 IU/ml = RF+) status were determined from baseline (BL) blood samples at the co-ordinating centre; erosions (yes/no) were recorded from medical notes. Missing data resulting from anti-CCP assay failure were imputed using multiple imputation. Patients who were anti-CCP+ and/or RF+ and had erosions were classified as having poor prognosis (PP); all other patients were classified as not having poor prognosis (NPP). Patients completed the Health Assessment Questionnaire (HAQ) and the Disease Activity Score (DAS28) was calculated at BL, 6 months and 12 months. The DAS28 and HAQ scores of the prognostic groups were compared at each assessment using linear regression, adjusted for age, gender and disease duration. <h3>Results</h3> In total, 1179 (PP = 182 [15.4%]) MTX-starters and 1152 (PP = 467 [40.5%]) biologic-starters were included (BL characteristics in Table). For MTX-starters, PP and NPP patients had similar DAS28, whereas for biologic-starters, PP patients had lower DAS28 compared to NPP patients after baseline (adjusted mean difference [95% CI]: MTX-starters BL = 0.1 [-0.1, 0.3]; 6 months = -0.1 [-0.3, 0.2]; 12 months = -0.1 [-0.4, 0.2]; biologic-starters BL = -0.1 [-0.2, 0.0]; 6 months = -0.2 [-0.4, 0.0]; 12 months = -0.4 [-0.6, -0.1]). HAQ scores were similar between PP and NPP patients in both cohorts (adjusted mean difference [95% CI]: MTX-starters BL = 0.08 [-0.04, 0.20]; 6 months = 0.02 [-0.11, 0.15]; 12 months = -0.03 [-0.17, 0.10]; biologic-starters BL = 0.00 [-0.09, 0.08]; 6 months = 0.00 [-0.12, 0.13]; 12 months = 0.01 [-0.14, 0.16]). <h3>Conclusion</h3> PP and NPP MTX-starters had similar outcomes. For biologic-starters, PP patients had lower disease activity after baseline; knowledge of these prognostic factors may have prompted more intensive assessment of PP patients after starting treatment. <h3>Disclosure of Interests</h3> James Gwinnutt: None declared, Kimme Hyrich Grant/research support from: Grants to institution: BMS, Pfizer, UCB, Mark Lunt: None declared, Darren Plant: None declared, Nisha Nair: None declared, Anne Barton: None declared, Suzanne Verstappen: None declared