LAUSR

Objectives: To study the differences in severity marker and disease activity in patients with RA and ILD and patients with RA without DILD, and to identify factors associated with ILD in RA patients. Methods: Design:Observational case-control study.Patients: consecutive RA-patients (ACR/EULAR 2010 criteria) with ILD (American Thoracic Society) selected from a prospective cohort from Regional Hospital and Virgen Victoria Hospital of Málaga were included. Controls: RA-patients without ILD. Sex-age matched controls were collected from a prospective cohort of Regional Hospital.Protocol: RA Patients are reviewed every six months in general clinic and patients with biological terapy every three months. All patients are reviewed according to a protocol with systematic data collection. The data of patients with RA and ILD are also collected in a database according to a specific protocol for these patients. The day that was reviewed the last time in consultation will be marked as inclusion date. Data will be collected on the date of inclusion and their clinical records.Outcomes: Difference in severity marker in both groups on the date of inclusion (RF, ACPA, erosive arthritis); in disease Activity Score (DAS28-ESR) and Health Assessment Questionnaire (HAQ); description of modifying antirheumatic drugs (DMARDs);Variables: Demographic, clinical-analytical variables: number of tender joints (TJ), number of swollen joints (SJ), CRP, ESR, general evaluation,DAS28-ESR, HAQ and adverse effects (description, severity and number).Statistical analysis: Descriptive and paired T-test or Chi-square test followed by binary logistic regression (RLB) (Vd:ILD in patients with RA). Results: Fifty-three patients were included, 29 RA with ILD and 24 RA controls. The differences between clinical and epidemiological characteristcs to cases and controls are shown in table 1. RA patients with ILD showed more months with RA duration (p=0.002), more number of exsmokers (p=0.003), erosive arthritis (p=0.011) and ACPA positive (P=0.008). No significant differences in the mean of DAS28 in cases and controls were observed (2.61 vs 2.68; p=0.789), but RA patients with ILD presented worse in physical function parameters by HAQ (1.12 VS 0.63; P=0.032). All patients were treated with disease modifying antirheumatic drugs (DMARDs). RA patients with ILD had: 5 (17.2%) monotherapy with bDMARDs, 17 (58.62) monotherapy with sDMARD and 7 (24.1) sDMARDs with a bDMARDs. In multivariate analysis, the independent variables that were associated with ILD in RA patients were: ACPA elevated (OR [IC95%] =5.0 [1.2–9.9]; p=0.023) and RA duration (months) (OR [IC95%]=1.1 [1.0–1,2]; p=0.037). This model would explain 28% of the variability of the ILD in RA (R2=0.28). Conclusions: The evolution time of arthritis and the presence of ACPA to high titres (>340) were the predictors of ILD in patients with RA in our study. More prospective studies with a greater number of patients are necessary to identify the possible association. Disclosure of Interest: None declared