Pos0163 Socioeconomic Status and Its Relationship With the Severity of the Course of Rheumatoid Arthritis: A Large Longitudinal Study

Background: The relationship between low socioeconomic status (SES) and rheumatoid arthritis (RA) severity is described in varying degrees in the literature. Studies with a long follow-up are limited and the relationship with the long-term outcomes as sustained DMARD-free remission (SDFR) is unknown. Objectives: To study the association between SES, and SES-related factors, with the disease activity score (DAS), and the chance of achieving SDFR. Methods: 789 RA-patients from the Leiden Early Arthritis Clinic (included between 2008-2022) were studied. Patients received DAS-steered treatment. SES was assessed by educational attainment, categorized as low (no/primary education), intermediate (secondary education) or high (college/university). DAS44 was measured at baseline, 4 and 12 months. SDFR was studied during median 6 (4-8) years follow-up and was defined as the sustained absence (≥ 1 year) of synovitis after discontinuing DMARDs. Mediation analysis was performed to evaluate if the association of SES with DAS was mediated by patient delay, BMI, smoking or work -related physical strain (blue/white collar occupation). Results: Patients with low educational attainment were older, had a higher BMI, more often had a blue-collar job, and smoked more frequently. Additionally, they had a higher DAS44 (β=0.34,95%CI=0.14-0.54,p=0.007). The DAS-components VAS general health and TJC did not differ between SES-groups, but the low SES-group more often had an increased ESR and more swollen joints (59% vs. 48%,p<0.001 and 6 vs. 5,p=0.023, respectively). The higher DAS at RA-presentation was not mediated by patient delay, smoking, BMI or work-related physical strain. Across three consecutive visits, differences in DAS between SES-groups decreased and disappeared after one year (Figure 1A). Additionally, patients with a low SES had a similar chance of achieving SDFR (HR=1.0, 95%CI=0.7-1.5, p=0.998; Figure 1B). Conclusion: RA-patients with a low SES presented with higher inflammation scores at diagnosis. This was not explained by common SES-related factors. Nevertheless, treat-to-target strategy resulted in a comparable disease severity. These data emphasize the relevance of SES and standardized treatment in RA. REFERENCES: NIL. Acknowledgements: NIL. Disclosure of Interests: None declared.