Bin Yoo

So Hye Nam, M.D., Byeongzu Ghang, M.D., Ph.D., Jungsun Lee, M.D., Ph.D., Doo-Ho Lim, M.D., Ph.D., Soo Min Ahn, M.D., Ji Seon Oh, M.D., Ph.D., Seokchan Hong, M.D., Ph.D., Yong-Gil Kim, M.D., Ph.D., Chang-Keun Lee, M.D., Ph.D., Soo Jeong Nam, M.D., Ph.D., Bin Yoo, M.D., Ph.D.. J Rheum Dis -0001;0:. https://doi.org/10.4078/jrd.2026.0078

Background/Objectives: Tumor necrosis factor (TNF) inhibitors are widely used in ankylosing spondylitis (AS), but data on cancer risk in this young population remain limited. We aimed to identify factors associated with cancer during TNF inhibitor therapy and evaluate age-specific risks in Asian patients with AS. Methods: We analyzed 810 AS patients who initiated TNF inhibitors between 2003 and 2023 at a Korean tertiary center. Cox regression assessed cancer predictors; when sparse data limited conventional models, Firth’s penalized likelihood was applied. Kaplan–Meier curves compared cumulative cancer incidence by age. Results: Over a mean follow-up of 7 years, cancer incidence was 323 per 100,000 person-years. Patients with cancer were older (48.6 vs. 39.0 years, p = 0.002) and more likely to have hypertension (33.3% vs. 14.6%, p = 0.041). In multivariable analysis, only age remained significant, with each year increasing hazard by 5.7%. Stratified analyses showed rising risks: HR 2.0 (≥30 vs. <30 years), 3.6 (≥40), 6.0 (≥50), and 8.8 (≥60). Risk profiles differed by age: in patients aged <40 years, female sex and elevated ESR were associated with cancer, while in patients aged ≥40 years, only age was associated. Thyroid cancer predominated in younger patients and lung cancer in older patients. Conclusions: In this long-term Korean cohort of patients with AS treated with TNF inhibitors, age was the primary independent risk factor, though determinants varied across age groups. These findings underscore the need for age-specific cancer risk assessment in AS.

Background: Pauci-immune glomerulonephritis (GN) is a typical renal manifestation of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). However, patients positive for ANCA can present with kidney pathologies other than pauci-immune GN. This study aimed to investigate and compare the characteristics of ANCA-positive patients diagnosed with pauci-immune GN to those with non-pauci-immune kidney diseases, based on kidney biopsy findings. Methods: We retrospectively analyzed the electronic medical records of ANCA-positive patients who underwent kidney biopsy from January 2010 to October 2023 at a single tertiary center in Seoul, Republic of Korea. Logistic regression analysis was performed to identify variables associated with the diagnosis of pauci-immune GN in this cohort. Results: Of 268 ANCA-positive patients, 195 (72.8%) were diagnosed with pauci-immune GN, while 73 (27.2%) had other kidney diseases. The most common pathologies in the non-pauci-immune GN group were IgA nephropathy (20.5%) and lupus nephritis (16.4%). Compared to the non-pauci-immune GN group, patients with pauci-immune GN exhibited higher platelet counts and C-reactive protein (CRP) levels, along with lower estimated glomerular filtration rate (eGFR). Urine abnormalities, categorized by the presence or absence of hematuria and/or proteinuria, differed significantly between the groups. Multivariate analysis identified hematuria and pulmonary involvement as significant predictors of pauci-immune GN. Conclusions: Approximately 70% of our ANCA-positive patients who underwent kidney biopsy were diagnosed with pauci-immune GN. Predictive factors for pauci-immune GN included platelet count, CRP levels, eGFR, hematuria, and pulmonary involvement. Identifying these clinical and laboratory markers may be valuable for improving the diagnostic approach towards AAV-related kidney manifestations. Graphical

Soo Min Ahn, M.D., Ph.D., Ji Seon Oh, M.D., Ph.D., Yong-Gil Kim, M.D., Ph.D., Chang-Keun Lee, M.D., Ph.D., Bin Yoo, M.D., Ph.D., Seokchan Hong, M.D., Ph.D.. J Rheum Dis -0001;0:. https://doi.org/10.4078/jrd.2025.0081

Background/Objectives: Ankylosing spondylitis (AS) is a chronic inflammatory disease frequently associated with acute uveitis (AU). Adalimumab, a monoclonal tumor necrosis factor (TNF) inhibitor, is widely used to manage AS and AU. While biologic tapering is recommended in stable AS, its impact on uveitis recurrence remains unclear. Methods: This real-world retrospective cohort study analyzed 65 AS patients with a history of AU who received adalimumab for ≥6 months. Time-dependent covariates, including the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), erythrocyte sedimentation rate (ESR), and adalimumab dosing interval, were incorporated into a logistic regression model using generalized estimating equations to identify risk factors for uveitis recurrence. Uveitis recurrence rates were compared among different dosing intervals: every 2 weeks (q2w), every 3 weeks (q3w), and every 4 weeks or longer (q4w+). Results: Among the 65 patients, 27 (41.5%) experienced a total of 50 AU flares during adalimumab treatment. Recurrence rates increased with dosing interval extension (1.5% for q2w, 3.6% for q3w, and 4.0% for q4w+; p = 0.036). In adjusted logistic analysis, the odds ratio (OR) for AU recurrence was significantly higher for q3w (OR = 3.766) and q4w+ (OR = 4.916) compared to q2w. Other factors, including age, sex, ESR, and BASDAI, were not significantly associated with uveitis recurrence. Conclusions: Extended dosing intervals of adalimumab in AS patients with prior AU may be associated with a higher prevalence of uveitis recurrence, even when axial symptoms remain controlled. Therefore, adalimumab spacing strategies should be implemented with caution in these patients to minimize the risk of uveitis recurrence.

Objective: To detect spondyloarthritis (SpA) and evaluate risk factors in patients with inflammatory bowel disease (IBD) during biologic or Janus kinase inhibitor (JAKi) treatment. Methods: This was a retrospective cohort study of patients with IBD receiving biologics or JAKi, excluding prior SpA cases. We identified patients who developed musculoskeletal (MSK) symptoms during IBD treatment. SpA was diagnosed after a clinical evaluation by a rheumatologist alongside imaging analysis of conventional radiographs and HLA-B27 determination. Magnetic resonance imaging of the sacroiliac joints was performed only in cases where the conventional radiograph was inconclusive. Results: Of 1649 patients with IBD receiving biologic or JAKi treatment (Crohn disease: 1335; ulcerative colitis [UC]: 314), 96 (5.8%) were excluded due to a prior SpA diagnosis. Among the remaining 1553 patients, 106 (6.8%) developed MSK symptoms during IBD treatment, and 30 (1.9%) were diagnosed with SpA (axial: 20; peripheral: 10) during the follow-up (median 5.2 [IQR 3.4-7.5] years). Risk factors for SpA in these patients included a partial Mayo score for UC at the time of onset of MSK symptoms (hazard ratio [HR] 1.57; P = 0.03) and HLA-B27 positivity (HR 3.70; P = 0.004). As well as IBD treatment, 23/30 (77%) patients with SpA used nonsteroidal antiinflammatory drugs (NSAIDs). IBD disease activity did not worsen during treatment, regardless of NSAID use. Conclusion: During a median follow-up of 5.2 years, 6.8% of patients with IBD undergoing biologic or JAKi treatment developed MSK symptoms, with one-third subsequently diagnosed with SpA. HLA-B27 positivity and higher UC disease activity were associated with an increased risk of SpA.

Soo Min Ahn, M.D., Ph.D., Seonok Kim, MSc., Ye-Jee Kim, Ph.D., Seokchan Hong, M.D., Ph.D., Chang-Keun Lee, M.D., Ph.D., Bin Yoo, M.D., Ph.D., Ji Seon Oh, M.D., Ph.D., Yong-Gil Kim, M.D., Ph.D.. J Rheum Dis 2025;32:113-21. https://doi.org/10.4078/jrd.2024.0104

Objectives This study aimed to assess the association between obesity or changes in body mass index (BMI) and the risk of RA considering the abdominal obesity status. Methods We included individuals aged 23 to 60 who underwent a national health examination in 2012–2013 (baseline) and four years prior. Obesity was defined by a BMI ≥ 25 kg/m². The change in BMI over 4 years was divided into quartiles. Cox proportional hazard analysis was performed to assess the association of obesity and BMI change with the risk of RA. Results A total of 6,207,246 subjects were included, and 7,859 incident cases of RA were identified. Obesity was associated with a reduced risk of RA in males (HR 0.78, 95% CI 0.71–0.85) and females (HR 0.91, 95% CI 0.85–0.97). In subgroup analysis according to abdominal obesity status, the associations were observed for obesity with normal waist circumference (WC) in males (HR 0.75, 95% CI 0.67–0.84) and females (HR 0.88, 95% CI 0.81–0.95). In terms of BMI change, compared to the stable BMI group (quartile 2), the third (HR 0.92, CI 0.85–0.99) and highest quartile (HR 0.89, CI 0.83–0.96) showed an inverse association with the risk of RA in females, particularly in those with normal WC. Conclusion Obesity was associated with a lower risk of RA, especially among individuals with a normal WC. Increased BMI was also associated with a lower risk of RA, but this association was mainly observed in females and specifically for those with normal WC.

Objective To identify the risk factors for relapse of idiopathic inflammatory myopathies (IIMs). Methods Patients who were newly diagnosed with IIMs and underwent muscle biopsy between 2000 and 2017 at Asan Medical Center were retrospectively reviewed. The relapse of IIMs was defined as the recurrence of muscle or cutaneous manifestations with a ≥50% increase in glucocorticoid dosage after reaching the low-dose glucocorticoid phase with clinically significant improvement. The factors associated with the relapse of IIMs were investigated by Cox proportional hazards analysis. Results Of 105 patients with IIMs, relapse was observed in 65 patients (62%). The titer of antinuclear antibody (ANA) was higher in the relapse group than in the non-relapse group (P = 0.033). Multivariable analysis showed that the relapse of IIMs was significantly associated with histopathologic features consistent with IIMs (hazard ratio [HR], 1.69; 95% confidence interval [CI], 1.01–2.83, P = 0.045) and the use of immunosuppressants before relapse (HR, 0.50; 95% CI, 0.29–0.86, P = 0.013). Doubling of ANA titer was also associated with relapse, albeit without statistical significance (HR, 1.13; 95% CI, 1.00–1.27, P = 0.052). Conclusion In patients with IIMs, the use of immunosuppressants had a significant negative association with relapse. Administering immunosuppressants from the early period during the initial glucocorticoid tapering phase may be useful in reducing the risk of relapse in patients with IIMs. Key Points • Since idiopathic inflammatory myopathies (IIMs) have a low prevalence, it is poorly understood which factors are associated with the relapse of IIMs. • In this study, about two-thirds of 105 patients with IIMs experienced a relapse of IIMs. • The risk of relapse in patients with IIMs was negatively associated with the use of immunosuppressants during glucocorticoid tapering and low-dose glucocorticoid phase. • Even in less severe cases, the use of immunosuppressants might be a good option for the management of IIMs.