Machine learning models with time-series clinical features to predict radiographic progression in patients with ankylosing spondylitis

( Bon San Koo ),( Miso Jang ),( Ji Seon Oh ),( Keewon Shin ),( Seunghun Lee ),( Kyung Bin Joo ),( Namkug Kim ),( Tae-hwan Kim ) 대한류마티스학회 2024 대한류마티스학회지 Vol.31 No.2

Objective: Ankylosing spondylitis (AS) is chronic inflammatory arthritis causing structural damage and radiographic progression to the spine due to repeated and continuous inflammation over a long period. This study establishes the application of machine learning models to predict radiographic progression in AS patients using time-series data from electronic medical records (EMRs). Methods: EMR data, including baseline characteristics, laboratory findings, drug administration, and modified Stoke AS Spine Score (mSASSS), were collected from 1,123 AS patients between January 2001 and December 2018 at a single center at the time of first (T₁), second (T₂), and third (T₃) visits. The radiographic progression of the (n+1)th visit (P_n+1=(mSASSS_n+1-mSASSS_n)/(T_n+1-T_n)≥1 unit per year) was predicted using follow-up visit datasets from T₁ to T_n. We used three machine learning methods (logistic regression with the least absolute shrinkage and selection operation, random forest, and extreme gradient boosting algorithms) with three-fold cross-validation. Results: The random forest model using the T₁ EMR dataset best predicted the radiographic progression P₂ among the machine learning models tested with a mean accuracy and area under the curves of 73.73% and 0.79, respectively. Among the T₁ variables, the most important variables for predicting radiographic progression were in the order of total mSASSS, age, and alkaline phosphatase. Conclusion: Prognosis predictive models using time-series data showed reasonable performance with clinical features of the first visit dataset when predicting radiographic progression.

Characteristics of Uveitis in Patients with Ankylosing Spondylitis in Korea: A Single-center Survey

( Bon San Koo ),( Jung Wook Lim ),( Ji Hui Shin ),( Tae-hwan Kim ) 대한류마티스학회 2018 대한류마티스학회지 Vol.25 No.1

Objective. Uveitis is the most common extra-articular manifestation occurring in patients with ankylosing spondylitis (AS). This study examined the characteristics of uveitis in patients with AS using a questionnaire survey. Methods. A questionnaire-based survey was given to patients enrolled in an AS registry at a rheumatology clinic in a tertiary hospital between September 2015 and December 2015. The patients responded to several questions and sub-questions related to uveitis. Results. A total of 750 patients participated in the survey. The number of patients diagnosed with uveitis in the ophthalmology department was 218 (29%). The most common symptoms in patients with uveitis were ocular injection (61%), eye pain (54%), and decreased visual acuity (51%). Interestingly, 91 of the 532 patients (17%) who had not been diagnosed with uveitis before also experienced similar symptoms, such as tearing, ocular injection, and eye pain. The number of patients who experienced a flare of uveitis more than once a year was 109 (50%), and 124 patients with uveitis responded that the treatment of AS had no significant effect on the prevention of uveitis recurrence. Conclusion. The clinical characteristics of uveitis that patients experience was investigated through surveys. Because uveitis in patients with AS is not well diagnosed and treated, active screening for suspected symptoms and the prevention of a recurrence is needed. (J Rheum Dis 2018;25:28-33)

Reliability and Quality of Korean YouTube Videos for Education Regarding Gout

Koo Bon San,Kim Dam,Jun Jae-Bum 대한의학회 2021 Journal of Korean medical science Vol.36 No.45

Background: YouTube has become an increasingly popular educational tool and an important source of healthcare information. We investigated the reliability and quality of the information in Korean-language YouTube videos about gout. Methods: We performed a comprehensive electronic search on April 2, 2021, using the following keywords—“gout,” “acute gout,” “gouty arthritis,” “gout treatment,” and “gout attack”—and identified 140 videos in the Korean language. Two rheumatologists then categorized the videos into three groups: “useful,” “misleading,” and “personal experience.” Reliability was determined using a five-item questionnaire modified from the DISCERN validation tool, and overall quality scores were based on the Global Quality Scale (GQS). Results: Among the 140 videos identified, 105 (75.0%), 29 (20.7%), and 6 (4.3%) were categorized as “useful,” “misleading,” and “personal experience,” respectively. Most videos in the “useful” group were created by rheumatologists (70.5%). The mean DISCERN and GQS scores in the “useful” group (3.3 ± 1.0 and 3.8 ± 0.7) were higher than those in the “misleading” (0.9 ± 1.0 and 1.9 ± 0.6) and “personal experience” groups (0.8 ± 1.2 and 2.0 ± 0.8) (P < 0.001 for both the DISCERN and GQS tools). Conclusion: Approximately 75% of YouTube videos that contain educational material regarding gout were useful; however, we observed some inaccuracies in the medical information provided. Healthcare professionals should closely monitor media content and actively participate in the development of videos that provide accurate medical information.

Distribution of serum uric acid levels and prevalence of hyper- and hypouricemia in a Korean general population of 172,970

( Bon San Koo ),( Hye-jin Jeong ),( Chang-nam Son ),( Sang-hyon Kim ),( Hyun Jung Kim ),( Gheun-ho Kim ),( Jae-bum Jun ) 대한내과학회 2021 The Korean Journal of Internal Medicine Vol.36 No.0

Background/Aims: We investigated the distribution of serum uric acid (SUA) levels and estimated the prevalence of hyperuricemia and hypouricemia in the Korean population. Methods: This cross-sectional study used data from the Korean Genome and Epidemiology Study and included 172,970 participants (58,981 men and 113,989 women) aged 40 to 79 years. Hypouricemia and hyperuricemia were defined as SUA level ≤ 2.0 mg/dL and > 7 mg/dL, respectively. The prevalence of hyperuricemia and hypouricemia was evaluated by age and sex. Results: The mean SUA levels were significantly higher in men than in women (5.71 ± 1.27 mg/dL vs. 4.21 ± 0.96 mg/dL, p < 0.001). The mean SUA levels and prevalence of hyperuricemia increased with age in women but not in men. The overall prevalence of hyperuricemia and that in men and women was 50.82, 133.25, and 8.17 per 1,000 persons, respectively; the overall prevalence of hypouricemia and that in men and women was 4.16, 1.10, and 5.75 per 1,000 persons, respectively. The prevalence of hypouricemia in men was similar across all age groups; however, that in women was the highest in the age group of 40 to 49 years and the lowest in the age group of 50 to 59 years. Conclusions: The distribution of SUA levels and prevalence of hyperuricemia and hypouricemia differed according to age and sex. Age and sex should be considered in studies on uric acid-related diseases.

J-shaped Relationship Between Chronic Kidney Disease and Serum Uric Acid Levels: A Cross-sectional Study on the Korean Population

( Bon San Koo ),( Hye-jin Jeong ),( Chang-nam Son ),( Sang-hyon Kim ),( Gheun-ho Kim ),( Jae-bum Jun ) 대한류마티스학회 2021 대한류마티스학회지 Vol.28 No.4

Objective. Both hypouricemia and hyperuricemia are reportedly associated with reduced kidney function. This study investigated the association between uric acid levels and the risk of reduced renal function in men and women. Methods. We conducted a cross-sectional study using data from a government-funded health examinee cohort of a Korean genome and epidemiological study. A total of 172,970 participants (58,981 men, 113,989 women) aged 40∼79 years were included. A logistic regression test was performed, and the odds ratio (OR) and 95% confidence interval (CI) were calculated to examine the relationship between stratified uric acid levels and the frequency of chronic kidney disease. Results. As the uric acid level increased, the risk of reduced renal function increased. Moreover, for uric acid levels ≤2.0 mg/dL, the risk of reduced renal function was higher than that of the reference group. Among the total, man, and woman groups, a statistically significant association was observed in men (OR 1.71, 95% CI 0.945∼3.111, OR 5.003, 95% CI 1.405∼17.809, and OR 1.377, 95% CI 0.696∼2.724, respectively). Conclusion. The OR of reduced renal function according to uric acid levels formed a J-shaped curve in both genders. (J Rheum Dis 2021;28:225-233)

Mortality in patients with rheumatoid arthritis-associated interstitial lung disease treated with an anti-tumor necrosis factor agent

( Bon San Koo ),( Seok Chan Hong ),( You Jae Kim ),( Yong Gil Kim ),( Chang Keun Lee ),( Bin Yoo ) 대한내과학회 2015 The Korean Journal of Internal Medicine Vol.30 No.1

Background/Aims: To evaluate the impact on mortality of anti-tumor necrosis factor (anti-TNF) treatment of rheumatoid arthritis-associated interstitial lung disease (RA-ILD). Methods: We retrospectively reviewed the medical records of 100 RA-ILD patients who visited our tertiary care medical center between 2004 and 2011, identified those treated with an anti-TNF agent, divided patients into non-survivor and survivor groups and evaluated their clinical characteristics and causes of death. Results: A total of 24 RA-ILD patients received anti-TNF therapy, of whom six died (25%). Mean age at initiation of anti-TNF therapy was significantly higher in the nonsurvivor versus survivor group (76 years [range, 66 to 85] vs. 64 years [range, 50 to 81], respectively; p = 0.043). The mean duration of anti-TNF treatment in the non-survivor group was shorter (7 months [range, 2 to 14] vs. 23 months [range, 2 to 58], respectively; p = 0.030). The duration of anti-TNF therapy in all nonsurviving patients was < 12 months. Pulmonary function test results at ILD diagnosis, and cumulative doses of disease-modifying drugs and steroids, did not differ between groups. Five of the six deaths (83%) were related to lung disease, including two diffuse alveolar hemorrhages, two cases of acute exacerbation of ILD, and one of pneumonia. The sixth patient died of septic shock following septic arthritis of the knee. Conclusions: Lung complications can occur within months of initial anti-TNF treatment in older RA-ILD patients; therefore, anti-TNF therapy should be used with caution in these patients.

Effect of biologics in the level of cytokines in the synovial fluid of patients with ankylosing spondylitis

( Bon San Koo ),( Sungsin Jo ),( Eunji Kwon ),( Ji Hui Shin ),( Jin-wuk Hur ),( Tae-hwan Kim ) 대한내과학회 2020 The Korean Journal of Internal Medicine Vol.35 No.2

Background/Aims: Biologics are very effective drugs for patients with ankylosing spondylitis (AS). However, there are patients who are not responding to biologics. This study aimed to evaluate the level of tumor necrosis factor α (TNF-α), interleukin (IL)-23, and IL-17 from synovial fluid in patients with AS and rheumatoid arthritis (RA) and differences of the level of those cytokines according to drugs. Methods: Synovial fluid was obtained from 34 patients (42 samples) with AS and 45 patients (47 samples) with RA with active arthritis of the knee, and the cytokine levels were measured. The differences in the levels between patients treated with and without biologics (biologics and non-biologics groups, respectively) were analyzed in AS and RA. The correlations between cytokines were examined in the non-biologics and biologics groups. Results: The TNF-α level in AS was significantly lower than that in RA (p = 0.016). The IL-17 and IL-23 levels were not different between AS and RA (p = 0.409 and p = 0.562, respectively). In AS and RA, TNF-α, IL-17, and IL-23 showed good correlation among each other in the non-biologics group. However, there was no significant correlation in biologics group. In some patients in the AS group, the IL-17 or IL-23 level was markedly elevated in the biologics group. Conclusions: Treatment with biologics affects the cytokine profile in inflammatory synovial fluid in patients with both AS and RA. Furthermore, IL-23 and IL-17 cytokine might be an important factor in some patients who are unresponsive to biologics in AS.

The Incidence of Uveitis in Ankylosing Spondylitis Patients Undergoing Tumor Necrosis Factor Inhibiting Therapy in Korea

( Bon San Koo ),( Seokchan Hong ),( You Jae Kim ),( Chang Keun Lee ),( Bin Yoo ),( Yong Gil Kim ) 대한류마티스학회 2015 대한류마티스학회지 Vol.22 No.5

Objective. The purpose of this study is to evaluate the outcome of uveitis in ankylosing spondylitis (AS) during tumor necrosis factor (TNF)-inhibiting therapy and to compare the incidence rate of uveitis in infliximab, adalimumab, and etanercept. Methods. A retrospective evaluation was performed in AS patients who had started TNF-inhibiting therapy from June 2003 to June 2011. The clinical characteristics of patients with documented uveitis were evaluated. Results. Among 316 patients treated with TNF inhibitor, 26 patients (8%) had experienced uveitis during TNF-inhibiting therapy. Among them, 15 patients were treated with etanercept, eight with adalimumab, and three with infliximab. The overall incidence rate of uveitis flare during therapy with TNF inhibitor was 46 per 1,000 person-years (pys) (95% confidence interval [CI], 32 to 64). The incidence rate did not differ between TNF inhibitors, with 54/1,000 pys (95% CI, 34 to 81) for etanercept, 46/1,000 pys (95% CI, 21 to 87) for adalimumab, and 22/1,000 pys (95% CI, 5 to 64) for infliximab. Fourteen patients experienced a first episode of uveitis. The overall incidence rate of new onset-uveitis after therapy with TNF inhibitor was 19 per 1,000 pys (95% CI, 10 to 31). The incidence rate for etanercept was 24/1,000 pys (95% CI, 12 to 45); adalimumab, 15/1,000 pys (95% CI, 3 to 45); and infliximab, 7/1,000 pys (95% CI, 0 to 40). There was no statistical difference in the incidence of uveitis flare or the cumulative uveitis-free rate among the three TNF inhibitors. Conclusion. The relative rate of uveitis, including the first episode, was determined using the TNF inhibitor. However, there was no difference in the incidence rate of uveitis among the three TNF inhibitors. (J Rheum Dis 2015;22:288-292)

Clinical Characteristics of Patients with Rheumatoid Arthritis Who have Sustained High Erythrocyte Sedimentation Rates after Clinical Remission

( Bon San Koo ),( Seok Chan Hong ),( You Jae Kim ),( Yong Gil Kim ),( Chang Keun Lee ),( Bin Yoo ) 대한류마티스학회 2014 대한류마티스학회지 Vol.21 No.1

Objective. The aim of this study is to determine the clinical characteristics of patients with rheumatoid arthritis (RA) sustaining high erythrocyte sedimentation rate (ESR) despite clinical remission. Methods. This cross-sectional study involved 91 patients, who visited a tertiary medical center. Patients underwent laboratory tests and a physical examination by a rheumatologist. The disease activity score (DAS) was calculated and patients who were in remission (defined as DAS28-CRP <2.6) were selected. Patients were divided into two groups: those with high and low ESRs (≥40 and <40 mm/hr, respectively). Results. DAS 28-CRP scores revealed that 61 of the 91 patients were in remission. Of these 61 patients, 15 and 46 were allocated to the high and low ESR groups, respectively. Compared to the low ESR group, the high ESR group had a longer disease duration (99.2±60.2 vs. 59.1±48.9 months), significantly higher white blood cell counts, and CRP levels, total modified Sharp radiographic joint scores, and erosion scores, as well as significantly lower hemoglobin, albumin and alanine aminotransferase levels. Conclusion. Patients who have high ESRs despite their remission status may show progressive radiographic change. In such patients, additional treatments that decreases the inflammation and prevents radiological progression should be considered.

소성 굴 패각을 활용한 알칼리 활성 시멘트에 관한 기초 연구

구본산(Koo, Bon San),장정국(Jang, Jeong Gook) 한국콘크리트학회 2018 한국콘크리트학회 학술대회 논문집 Vol.30 No.2