POS0031 VARIABILITY IN INITIAL MTX RESPONSE IN NEWLY DIAGNOSED RA PATIENTS WITH DISTINCT PRO SYMPTOM CLUSTERS: A LONGITUDINAL ANALYSIS OF THE CANADIAN EARLY ARTHRITIS COHORT
Authors: S.J. Bartlett, C.O. Bingham, O. Schieir, M.F. Valois, J. Pope, C. Thorne, L. Bessette, C.A. Hitchon, G. Boire, D. Tin, E. Keystone, G. Hazlewood, V. Bykerk, C. Investigators
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Growing research shows that across chronic diseases, patients grouped based co-occurring symptoms, known as "symptom clusters", experience variable disease outcomes, particularly if symptoms are under identified and undertreated. Moreover, if patients with distinct symptom clusters display unique patterns of treatment response, this information can help better match patients to conventional and advanced therapeutics to optimize disease control and QoL. We have previously applied a person-centered approach to group newly diagnosed early RA patients that yielded 4 distinct symptom clusters based on PROMIS patterns of PRO pain, fatigue, depression, and anxiety. <h3>Objectives:</h3> To compare early treatment response across new onset RA patients grouped into 4 distinct symptom clusters over the first 6-months of conventional MTX treatment. <h3>Methods:</h3> Data were from newly diagnosed RA patients (symptoms&lt; 1 year) enrolled in the Canadian Early Arthritis Cohort (CATCH) between Jan 2017 -Aug 2022 with active disease and who were starting MTX. Participants underwent standardized clinical assessments and completed the PROMIS29 at 0, 3, and 6 months. Latent Class Analysis yielded 4 groups: 1. Minimal Symptoms; 2. Mild Pain, Fatigue, Depression &amp; Anxiety; 3. Moderate Pain &amp; Fatigue; and 4. Moderate-Severe Pain, Fatigue, Depression &amp; Anxiety. MTX treatment response was assessed with CDAI disease activity, PROMIS Function and Participation measures. Multivariable mixed effects regression was used to estimate trajectories of disease activity, disability, and participation over the first 6-months of MTX treatment across symptom cluster groups updated at each time point adjusting for age, sex, race, education, smoking, obesity, comorbidities, symptom duration, seropositivity, and RA treatments. <h3>Results:</h3> The sample of 310 ERA adults had a mean (SD) age of 56 (14), and were mostly female (67%), White (78%) with a mean CDAI of 29.3 (13.2) at diagnosis. All were started on MTX, with no significant difference in MTX dose or strategy across symptom cluster groups (Table 1). All groups had high disease activity (CDAI) scores at enrolment, though patients reporting moderate-severe levels of pain, fatigue, depression, and anxiety were significantly younger, more often had a history of depression, had the highest mean CDAI scores, and greater impairments in function and participation than other groups. In adjusted regression models, all groups improved but patients with moderate-severe physical and emotional symptoms consistently displayed worse trajectories of disease activity, function, and participation over the 6-month follow-up period (Figure 1). <h3>Conclusion:</h3> Beyond disease activity at RA onset, evaluating the presence of specific symptom clusters in the first 6 months of new RA could better identify individuals at risk for poorer MTX response. These individuals may benefit from earlier, more aggressive pharmacologic and psychosocial interventions. Addressing both physical and emotional symptoms may improve physical and social function in early RA helping to preserve autonomy, workforce participation, and QOL. <b>Table 1.</b> <h3>REFERENCES:</h3> <b>NIL.</b> <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> Susan J. Bartlett Janssen, Abbvie, Pfizer, Sandoz, Organon, UCB, Lilly, Novartis, Merck, Organon, Clifton O Bingham: None declared, Orit Schieir: None declared, Marie-France Valois: None declared, Janet Pope Abbvie, Amgen, Celltrion, Myriad, Hofffmann-LaRoche, Janssenm Lillym Merck, Pfizerm, Sandoz, Sanofi-Genzyme, Samsung Bioepsis, Abbvie, Celltrion, Myriad, Lilly, Merck, Pfizer, Sandoz, Sanofi-Genzyme, Samsung Bioepsis, Amgen, Hoffman-LaRoche, Janssen, Abbvie, BMS, Lilly, Merck, Roche, Seattle Genetics, UCB, Carter Thorne Medexus, Abbvie, Centocor, Janssen, Medexus, Novartis, Pfizer, Sandoz, Sanofi, Pfizer, Louis Bessette Amgen, BMS, Janssen, UCB, Abbvie, Pfizer, Merck, Sanofi, Lilly, Novartis, TEVA, Fresenius Kabi, Sandoz, Organon, Amgen, BMS, Janssen, Roche, UCB, Abbvie, Pfizer, Merck, Sanofi, Lilly Novartis, TEVA, Fresenius Kabi, Sandoz, Organon, Amgen, BMS, Janssen, Roche, UCB, Abbvie, Pfizer, Merck, Celgene, Sanofi, Lilly, Novartis, Gilead, Carol A Hitchon Astra-Zeneca, Pfizer, UCB, Gilles Boire Astra Zenica, BMI, Lilly, Janssen, Merck, Pfiizer, Diane Tin: None declared, Edward Keystone AbbVie, Amgen, Celltrion, Myriad Autoimmune, F. Hoffmann-La Roche Inc, Janssen Inc, Lilly Pharmaceuticals, Merck, Pfizer, Sandoz, Sanofi-Genzyme, Samsung Bioepsis, Abbvie, Celltrion, Myriad, Lilly, Merck, Pfizer, Sandoz, Sanofi, Genzyne, Samsung Bioepsis, Myrad, Hoffman-LaRoche, Janssen, Amgen, Merck, Pfizer, Glen Hazlewood: None declared, Vivian Bykerk BMS, Janssen, Gilead, Pfizer, Sanofi, Aventis, UCB, Amgen, BMS, CATCH Investigators Pfizer Canada- Founding sponsor since 2007; AbbVie since 2011; Hoffman La Roche Limited since 2011; Sandoz Biopharmaceuticals Canada since 2019; Fresenius Kabi Canada and Organon Canada since 2021; Viatris Canada, Jamp Pharma (BIOJAMP), Nordic Pharma, and Celltrion Canada since 2023. Previous funding from Amgen Canada (2007-22); Janssen Canada (2011-16); UCB Canada and Bristol-Myers Squibb Canada (2011-18); Medexus Pharmaceuticals (2013-2022); Sanofi Genzyme (2016-17); Eli Lilly Canada (2016-20); Merck Canada (2017-21) and, Gilead Sciences Canada (2020-21).