POS0543 Difficult-to-treat rheumatoid arthritis: associated factors and persistence of treatment

<h2>Abstract</h2><h3>Background:</h3> The implementation of treat-to-target and tight control strategies has significantly improved outcomes for patients with rheumatoid arthritis (RA). However, some patients with RA fail to achieve low disease activity or remission even after multiple cycles of disease-modifying antirheumatic drugs (DMARDs). <h3>Objectives:</h3> To identify factors associated with difficult-to-treat rheumatoid arthritis (D2T RA) and analyze predictors of treatment persistence. <h3>Methods:</h3> Data from patients with RA from 13 centers in Brazil, followed up for 12 months in the PANLAR Register of Rheumatic Diseases (PANRED), were analyzed. Patients were classified as D2T RA based on the 2021 EULAR definition. Univariate and multivariate logistic regression models were applied, with associations quantified using Odds Ratio (OR) and its respective 95% confidence interval. <h3>Results:</h3> Among 572 patients included in the study, 209 (36.5%) were classified as having D2T RA. These patients were predominantly female (94.3% vs. 83.8%, p<0.001), had a lower mean age [55 years (SD 11.4) vs. 57 years (SD 11.1), p=0.08], longer disease duration [15.9 years (SD 9.0) vs. 10.3 years (SD 8.9), p<0.001], higher body mass index (BMI) [28.0 (SD 5.6) vs. 26.6 (SD 4.6), p=0.025], and a higher prevalence of comorbidities (52.7% vs. 34.0%, p<0.001) and erosive disease (69.4% vs. 46.1%, p<0.001). After adjusting for covariates in the multivariate model, the following factors were independently associated with D2T RA: female gender, younger age, longer disease duration, presence of comorbidities, and erosive disease (Table 1). Of the 209 patients with D2T RA, 59 (28.2%) discontinued treatment during the 12-month follow-up period, with 45 (76.3%) doing so permanently. The most common reasons for treatment discontinuation were loss of primary efficacy (37.3%) and medication-related adverse events (32.9%). A multivariate analysis was conducted to identify predictors of treatment discontinuation in patients with D2T RA (Table 2). In the final model, treatment group [biological (b) vs targeted synthetic (st) DMARDs] was a significant predictor of drug discontinuation. Patients receiving bDMARDs were five times more likely to permanently discontinue treatment [OR=5.1 (95% CI 1.04–25.2), p=0.04] compared to those receiving tsDMARDs. <h3>Conclusion:</h3> In this cohort of Brazilian patients with RA, female gender, younger age, longer disease duration, comorbidities, and erosive disease were significantly associated with D2T RA. Furthermore, the use of tsDMARDs was associated with longer treatment persistence in patients with D2T RA. <h3>REFERENCES:</h3> <b>NIL</b>. Table 1Univariate and Multivariate analyses of factors associated with difficult-to-treat rheumatoid arthritis.UnivariateMultivariateOR (95% CI)p-valueOR (95% CI)p-valueGender (Female/Male)3.19 (1.67-6.08)<0.0012.6 (1.28-5.26)0.008Age (years)0.99 (0.98-1.01)0.1900.96 (0.95-0.98<0.001Body mass index (kg/m²)1.05 (1.01-1.08)0.008Disease duration (Years)1.07 (1.05-1,09)<0.0011.06 (1.04-1.09)<0.001Comorbidities2.11 (1.49-2.99)<0.0012.05 (1.36-3.08)<0.001Smoking (current)1.21 (0.71-2.08)0.484Erosive disease2.62 (1.80-3.82)<0.0012.33 (1.54-3.52)<0.001Autoantibody positivity(RF and/or ACPA)1.27 (0.74-2.18)0.383 Table 2Multivariate logistic regression model for the outcome variable "permanent discontinuation of treatment" in patients with D2T RA.Initial modelFinal modelCoefficient (95% CI)p-valueCoefficient (95% CI)p-valueNumber of previous failures ofb/tsDMARD-0.07 (0.71-1.22)0.25Treatment group(b vs tsDMARD)1.36 (0.73-20.77)0.081.63 (1.04-25.21)0.04Autoantibody positivity(RF and/or ACPA)1.69 (0.43; 68.59)0.19Current smoking-0.88 (0.09; 1.96)0.21 <h3>Acknowledgements:</h3> PANLAR. <h3>Disclosure of Interests:</h3> Gilda Aparecida Ferreira: None declared, Gustavo Resende: None declared, Maria Fernanda Brandão de Resende Guimarães: None declared, Renê Donizeti Ribeiro de Oliveira: None declared, Samia Studart: None declared, Gilberto Loiola de Vasconcelos: None declared, Adriana Maria Kakehasi: None declared, Rina Dalva Neubarth Giorgi: None declared, Nathália de Carvalho Sacilotto: None declared, Viviane Angelina de Souza: None declared, Louise Fellet Barbosa: None declared, Barbara Stadler Kahlow: None declared, Cristiano Lupo: None declared, Manuella Lima Gomes Octrop: None declared, Claiton Viegas Brenol: None declared, Nicole Pamplona Bueno de Andrade: None declared, Ana Cristina Medeiros-Ribeiro: None declared, Ines Guimaraes Silveira: None declared, Julia Boechat Farani: None declared, Vander Fernandes: None declared, Jessica Perini Cardoso: None declared, Mariana Peixoto Guimarães e Silva de Souza: None declared, HUMBERTO MACHADO DE RESENDE: None declared, Thiago Schultz: None declared, Vítor Cruz: None declared, Daniel G. Fernández-Ávila: None declared, Nicolas Marin Zucaro: None declared, Maria Lorena Brance: None declared, Enrique R. Soriano THIS REGISTER RECEIVED IRRESTRICTED GRANT OF ABBVIE, PFIZER and JANSSEN. © The Authors 2025. This abstract is an open access article published in Annals of Rheumatic Diseases under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Neither EULAR nor the publisher make any representation as to the accuracy of the content. The authors are solely responsible for the content in their abstract including accuracy of the facts, statements, results, conclusion, citing resources etc.