Ab0639 Changes in Patients’ Characteristics, Seropositivity and Disease Activity Over Time in Patients With Rheumatoid Arthritis From 2009 to 2022 -Data From an Open Cohort Called Toyohashi Rheumatoid Arthritis Database (Trad)

Background: We feel that the clinical environment for rheumatoid arthritis (RA) is changing over the years. The one of changes in the clinical environment is advances in diagnosis and treatment. The introduction of joint ultrasound examinations and the clinical use of biological agents (Bio) and JAK inhibitors (JAKi) have made it possible to practice treat-to-target, and although there are still problems with the condition of RA patients being inadequate, overall, the condition of RA patients has improved from the past. Another major change is the change in the patient background of RA patients. Japan's population is aging rapidly, and by 2023, 29.1% of the population will be 65 years old or older. The aging of RA patients in Japan is progressing as well, and we feel that the patient background is gradually changing in actual clinical practice. In particular, the number of seronegative RA patients is increasing. We have been running an open cohort called the Toyohashi Rheumatoid Arthritis Database (TRAD) since 2009, making it possible to investigate changes in the patient background, drug treatment, and disease activity of RA patients over time. Objectives: Using TRAD, we investigated trends in patient demographics, serology, drug treatment, and disease activity in RA patients from 2009 to 2022. Methods: TRAD examines RA patients attending our department once a year at any time, based on basic information such as age, gender, and disease duration, details of antirheumatic drug treatment such as DMARD and glucocorticoid (GC) use, and disease activity evaluation using composite measures and remission evaluation using Boolean criteria are recorded. In this study, we summarized these trends from 2009 to 2022 and analyzed the characteristics of the changes. The Cochran-Armitage test was used for statistical analysis of changes over time, and p<0.05 was determined to be a statistically significant difference. Results: Data is shown in Table 1. The number of RA patients in TRAD increased from 642 in 2009 to 1008 in 2022. The average age of the population increased from 63.3 years old in 2009 to 68.9 years old in 2022. Although the RF positivity rate significantly increased over time in all patients, patients aged 64 years old or under and patients aged 65 years old or above, the ACPA positivity rate significantly decreased from 80.0% in 2009 to 74.9% in 2022 in all patients. This decrease of ACPA positive rate was significant in patients aged 65 years old or over but in 64 years old or under. Both RF- and ACPA-negative rate significantly increased over time (Figure 1). The MTX administration rate peaked at 66.9% in 2012 and has declined to 56.3% in 2022. The PSL administration rate will decrease from 38.5% in 2009 to 10.0% in 2022. Bio/JAKi were administered to a total of 476 patients in our department and % Bio/JAKi experienced increased from 19.8% in 2009 to 47.2% in 2022. The mean DAS28-ESR decreased from 3.87 in 2009 to 2.88 in 2022. The mean CRP decreased from 1.38mg/dl in 2009 to 0.53mg/dl in 2022. % mHAQ<0.5 significantly increase from 55.6% in 2009 to 78.1% in 2022. The remission rate in 2022 with DAS28-ESR, SDAI Boolean1.0 and Boolean 2.0 were 41.5%, 62.0%, 56.6% and 65.2%, respectively. Conclusion: As RA patients aged, an increase in RF-positive RA patients and an increase in ACPA-negative RA patients were observed. As a result, the rate of both RF- and ACPA-negative RA patients has increased. Prescription of GC have decreased and prescription of Bio/JAKi have increased over time. DAS28-ESR remission becomes more difficult to achieve than SDAI or Boolean remission, perhaps due increase in ESR as RA patients aged. REFERENCES: NIL. Acknowledgements: NIL. Disclosure of Interests: None declared.