Objective This study aimed to assess the prevalence of pain in patients with RA in clinical remission and analyze the demographic and clinical characteristics of those who experienced persistent pain despite remission status. Methods Data from 1,891 patients with RA registered on the Korean College of Rheumatology Biologics and Targeted Therapy registry were obtained. Remission was defined as a Disease Activity Score of 28 joints-erythrocyte sedimentation rate (ESR) <2.6. Pain intensity was classified as severe (pain visual analog scale [VAS] ≥7), moderate (4≤VAS<7), or mild (VAS <4). Results Our analysis showed that 52.6% of patients complained of severe pain at the start of or during switching biological disease-modifying anti-rheumatic drugs (bDMARDs) or targeted synthetic DMARDs (tsDMARDs). Despite having a 36.0% (n=680) remission rate after the use of bDMARDs or tsDMARDs at their 1-year follow-up, 21.5% (n=146) of these patients had moderate-to-severe pain, higher frequency of foot erosions, and comorbidities, such as mental illness, endocrine, renal, and neurological disorders, than patients with a milder degree of pain. The multivariable regression analysis showed that presence of foot erosions, neurological disorders, and use of corticosteroids were independently associated with moderate-to-severe pain in patients with RA despite being in remission. The level of ESR and use of Janus kinase inhibitors were inversely associated with moderate-to-severe pain. Conclusion Persistent pain and discomfort continue to be a problem for patients with RA in clinical remission. Continued research on insistent pain in patients with RA is warranted to better alleviate distress and improve the quality of life in patients.

Background Clinical characteristics and manifestations of psoriatic arthritis (PsA) have been extensively studied in western countries, yet data of Korean patients with PsA are very limited. We aimed to investigate the clinical traits of patients with PsA and dissect the characteristics of those with axial involvement. Methods In this observational study, we analyzed clinical data of 109 patients with PsA who were enrolled in the Korean College of Rheumatology Biologics and Targeted Therapy registry between December 2012 and March 2022 at the time point of initiating or switching to a biologic agent. Data from 2,221 patients with ankylosing spondylitis (AS) registered during the same period were also analyzed. We divided patients with PsA into patients with or without axial involvement and then added AS patients with psoriasis (total three subgroups) for comparative analyses. Results Asymmetric oligoarthritis was the most common clinical manifestation in patients with PsA, followed by symmetric polyarthritis and spondylitis. Our analysis indicated that methotrexate and sulfasalazine were the two most prescribed disease-modifying antirheumatic drugs for patients with PsA before starting biologic therapy. The patients with psoriatic spondylitis had more peripheral joint involvement ( P = 0.016), less prior uveitis ( P < 0.001), and lower human leukocyte antigen B27 (HLA-B27) positivity ( P < 0.001) than the AS patients with psoriasis. Furthermore, syndesmophytes and radiographic sacroiliitis were prevalent among patients with PsA and AS patients with psoriasis who had the HLA-B27 gene. Conclusion Our study shows that the degree of peripheral arthritis is less severe in Korean patients with PsA who require biologics and reestablishes that psoriatic spondylitis is a common and important clinical pattern in Korean patients with PsA. Trial Registration ClinicalTrials.gov Identifier: NCT01965132