Korean treatment recommendations for patients with axial spondyloarthritis

We aimed to develop evidence-based recommendations for treating axial spondylarthritis (axSpA) in Korea. The development committee was constructed, key clinical questions were determined, and the evidence was searched through online databases including MEDLINE, Embase, Cochrane, KoreaMed, and Kmbase. Systematic literature reviews were conducted, quality of evidence was determined, and draft recommendations were formulated according to the Grading of Recommendations Assessment, Development, and Evaluations methodology. Recommendations that reached 80% consensus among a voting panel were finalized. Three principles and 21 recommendations were determined. Recommendations 1 and 2 pertain to treatment strategies, regular disease status assessment, and rheumatologist-steered multidisciplinary management. Recommendations 3 and 4 strongly recommend patient education, exercise, and smoking cessation. Recommendations 5–12 address pharmacological treatment of active disease using nonsteroidal anti-inflammatory drugs, glucocorticoids, sulfasalazine, biologics, and Janus kinase inhibitors. Recommendations 13–16 address treatment in stable disease. We suggest against spa and acupuncture as therapies (Recommendation 17). Recommendations 18 and 19 pertain to total hip arthroplasty and spinal surgery. Monitoring of comorbidities and drug toxicities are recommended (Recommendations 20 and 21). Recommendations for axSpA treatment in a Korean context were developed based on comprehensive clinical questions and evidence. These are intended to guide best practice in the treatment of axSpA.

Korean treatment recommendations for patients with axial spondyloarthritis

We aimed to develop evidence-based recommendations for treating axial spondylarthritis (axSpA) in Korea. The development committee was constructed, key clinical questions were determined, and the evidence was searched through online databases including MEDLINE, Embase, Cochrane, KoreaMed, and KMbase. Systematic literature reviews were conducted, quality of evidence was determined, and draft recommendations were formulated according to the Grading of Recommendations Assessment, Development, and Evaluations methodology. Recommendations that reached 80% consensus among a voting panel were finalized. Three principles and 21 recommendations were determined. Recommendations 1 and 2 pertain to treatment strategies, regular disease status assessment, and rheumatologist-steered multidisciplinary management. Recommendations 3 and 4 strongly recommend patient education, exercise, and smoking cessation. Recommendations 5~12 address pharmacological treatment of active disease using nonsteroidal anti-inflammatory drugs, glucocorticoids, sulfasalazine, biologics, and Janus kinase inhibitors.Recommendations 13~16 address treatment in stable disease. We suggest against spa and acupuncture as therapies (Recommendation 17). Recommendations 18 and 19 pertain to total hip arthroplasty and spinal surgery. Monitoring of comorbidities and drug toxicities are recommended (Recommendations 20 and 21). Recommendations for axSpA treatment in a Korean context were developed based on comprehensive clinical questions and evidence. These are intended to guide best practice in the treatment of axSpA.

The Mechanism of the NLRP3 Inflammasome Activation and Pathogenic Implication in the Pathogenesis of Gout

The NACHT, LRR, and PYD-domains-containing protein 3 (NLRP3) inflammasome is an intracellular multi-protein signaling platform that is activated by cytosolic pattern-recognition receptors such as NLRs against endogenous and exogenous pathogens.Once it is activated by a variety of danger signals, recruitment and assembly of NLRP3, ASC, and pro-caspase-1 trigger the processing and release of pro-inflammatory cytokines including interleukin-1β (IL-1β) and IL-18. Multiple intracellular and extracellular structures and molecular mechanisms are involved in NLRP3 inflammasome activation. Gout is an autoinflammatory disease induced by inflammatory response through production of NLRP3 inflammasome-mediated proinflammatory cytokines such as IL-1β by deposition of monosodium urate (MSU) crystals in the articular joints and periarticular structures. NLRP3 inflammasome is considered a main therapeutic target in MSU crystal-induced inflammation in gout. Novel therapeutic strategies have been proposed to control acute flares of gouty arthritis and prophylaxis for gout flares through modulation of the NLRP3/IL-1 axis pathway. This review discusses the basic mechanism of NLRP3 inflammasome activation and the IL-1-induced inflammatory cascade and explains the NLRP3 inflammasome-induced pathogenic role in the pathogenesis of gout.

Baseline use of hydroxychloroquine or immunosuppressive drugs and the risk of coronavirus disease 2019

Background/Aims@#The preventive role of hydroxychloroquine (HCQ) on coronavirus disease 2019 (COVID-19) remains unclear. The aim of this study was to examine the effects of HCQ and other immunosuppressive drugs on the incidence of COVID-19. @*Methods@#The data were collected from the South Korea National Health Insurance Sharing-COVID-19 database. All individuals who underwent nasopharyngeal and oropharyngeal swab tests for COVID-19 from January 2020 to May 2020 are included. The association between COVID-19 risk and HCQ use was examined in a propensity score-matched population. Factors associated with COVID-19 were identified using multiple logistic regression analysis. @*Results@#Total 8,070 patients with COVID-19 and 121,050 negative controls were included from the database. Among all participants, 381 were HCQ users. In a propensity score-matched population, the incidence of COVID-19 was 7.1% in HCQ users and 6.8% in non-users. The odds ratio (OR) for HCQ use was 1.05 with a 95% confidence interval (CI) of 0.58 to 1.89. Among the subpopulation of patients with rheumatoid arthritis (RA), 33 were diagnosed with COVID-19 and 478 were not. Use of HCQ, glucocorticoids, or other immunosuppressive drugs was not associated with COVID-19 risk, whereas abatacept use was. Chronic lung disease was an independent risk factor for COVID-19 diagnosis in patients with RA (adjusted OR, 6.07; 95% CI, 1.10 to 33.59). @*Conclusions@#The risk of COVID-19 did not differ between HCQ users and non-users. Glucocorticoids, conventional disease-modifying antirheumatic drugs (DMARDs), and biological DMARDs other than abatacept did not increase the risk of COVID-19.

Activation of CpG-ODN-Induced TLR9 Signaling Inhibited by Interleukin-37 in U937 Human Macrophages

Purpose@#Interleukin-37 (IL-37) is an anti-inflammatory cytokine that inhibits a broad spectrum of inflammatory responses in various human cells, including neutrophils, macrophages, and endothelial cells. The aim of this study was to identify the role of IL-37 in toll-like receptor 9 (TLR9) signaling in human macrophages. @*Materials and Methods@#Human macrophage U937 cells treated with CpG-oligonucleotides (CpG-ODN), recombinant IL-37, or dexamethasone were used in an in vitro study. IL-37 small interfering RNA (siRNA) and TLR9 siRNA were used to silence endogenous IL-37 and TLR9, respectively. Expression levels of phosphorylated nuclear factor-κB (NF-κB), IκBα, IL-37, IL-1β, tumor necrosis factor-α (TNF-α), and IL-6 protein were assessed by real-time quantitative polymerase chain reaction and Western blotting. CpG-ODN-mediated IL-37 expression stimulated by dexamethasone was detected using immunofluorescent analysis. @*Results@#U937 cells treated with CpG-ODN induced activation of the NF-κB pathway and increased the expression of the pro-inflammatory cytokines IL-1β, TNF-α, and IL-6, but reduced that of IL-37. Recombinant IL-37 attenuated phosphorylation of NF-κB and IκBα and the expression of IL-1β, TNF-α, and IL-6 stimulated by CpG-ODN. Human macrophages transfected with IL-37 siRNA augmented the expression of IL-1β, TNF-α, and IL-6 mRNA and protein in cells treated with CpG-ODN. Dexamethasone markedly inhibited expression of pro-inflammatory cytokines in U937 cells, whereas IL-37 expression was increased with the addition of dexamethasone. Inflammatory responses elicited by CpG-ODN were dependent on an MyD88-TRAF6 pathway. IL-37 inhibited CpG-ODN-induced ubiquitination of TRAF6 in U937 macrophages. @*Conclusion@#IL-37 inhibits CpG-ODN-mediated inflammatory responses through regulation of a TRAF6- NF-κB pathway in human macrophages.

KOBIO, the First Web-based Korean Biologics Registry Operated With a Unified Platform Among Distinct Disease Entities

The KOrean College of Rheumatology BIOlogics and targeted therapy (KOBIO) registry is a nationwide observational cohort that captures detailed data on exposure of patients to biologic and targeted synthetic disease-modifying anti-rheumatic drugs (DMARDs). This registry was launched in December 2012 with an aim to prospectively investigate clinical manifestations and outcomes of patients with rheumatoid arthritis (RA), ankylosing spondylitis, and psoriatic arthritis who initiated a biologic or targeted synthetic DMARD or switched to another. Demographic data, disease activity, current treatment, adverse events, terms based on Medical Dictionary for Regulatory Activities, and so on are registered for patients who are then followed up annually in a web-based unified platform. The KOBIO registry also recruits and collects data of patients with RA on conventional DMARDs for comparison. As of today, more than 5,500 patients were enrolled from 47 academic and community Rheumatology centers across Korea. The KOBIO registry has evolved to become a powerful database for clinical research to improve clinical outcomes and quality of treatment.

Activation of CpG-ODN-Induced TLR9 Signaling Inhibited by Interleukin-37 in U937 Human Macrophages

Purpose@#Interleukin-37 (IL-37) is an anti-inflammatory cytokine that inhibits a broad spectrum of inflammatory responses in various human cells, including neutrophils, macrophages, and endothelial cells. The aim of this study was to identify the role of IL-37 in toll-like receptor 9 (TLR9) signaling in human macrophages. @*Materials and Methods@#Human macrophage U937 cells treated with CpG-oligonucleotides (CpG-ODN), recombinant IL-37, or dexamethasone were used in an in vitro study. IL-37 small interfering RNA (siRNA) and TLR9 siRNA were used to silence endogenous IL-37 and TLR9, respectively. Expression levels of phosphorylated nuclear factor-κB (NF-κB), IκBα, IL-37, IL-1β, tumor necrosis factor-α (TNF-α), and IL-6 protein were assessed by real-time quantitative polymerase chain reaction and Western blotting. CpG-ODN-mediated IL-37 expression stimulated by dexamethasone was detected using immunofluorescent analysis. @*Results@#U937 cells treated with CpG-ODN induced activation of the NF-κB pathway and increased the expression of the pro-inflammatory cytokines IL-1β, TNF-α, and IL-6, but reduced that of IL-37. Recombinant IL-37 attenuated phosphorylation of NF-κB and IκBα and the expression of IL-1β, TNF-α, and IL-6 stimulated by CpG-ODN. Human macrophages transfected with IL-37 siRNA augmented the expression of IL-1β, TNF-α, and IL-6 mRNA and protein in cells treated with CpG-ODN. Dexamethasone markedly inhibited expression of pro-inflammatory cytokines in U937 cells, whereas IL-37 expression was increased with the addition of dexamethasone. Inflammatory responses elicited by CpG-ODN were dependent on an MyD88-TRAF6 pathway. IL-37 inhibited CpG-ODN-induced ubiquitination of TRAF6 in U937 macrophages. @*Conclusion@#IL-37 inhibits CpG-ODN-mediated inflammatory responses through regulation of a TRAF6- NF-κB pathway in human macrophages.

KOBIO, the First Web-based Korean Biologics Registry Operated With a Unified Platform Among Distinct Disease Entities

The KOrean College of Rheumatology BIOlogics and targeted therapy (KOBIO) registry is a nationwide observational cohort that captures detailed data on exposure of patients to biologic and targeted synthetic disease-modifying anti-rheumatic drugs (DMARDs). This registry was launched in December 2012 with an aim to prospectively investigate clinical manifestations and outcomes of patients with rheumatoid arthritis (RA), ankylosing spondylitis, and psoriatic arthritis who initiated a biologic or targeted synthetic DMARD or switched to another. Demographic data, disease activity, current treatment, adverse events, terms based on Medical Dictionary for Regulatory Activities, and so on are registered for patients who are then followed up annually in a web-based unified platform. The KOBIO registry also recruits and collects data of patients with RA on conventional DMARDs for comparison. As of today, more than 5,500 patients were enrolled from 47 academic and community Rheumatology centers across Korea. The KOBIO registry has evolved to become a powerful database for clinical research to improve clinical outcomes and quality of treatment.

Ultrasound Findings were Associated With Radiographic Changes, But Not Clinical and Functional Outcomes in Hand Osteoarthritis

Objective@#. There is a debate over the relevance of ultrasound abnormalities to the pain, functional impairment, and radiologic severity in hand osteoarthritis (OA). This study aims to determine the association between ultrasound abnormalities and clinical, functional, and radiographic measures in hand OA. @*Methods@#. A total of 66 patients was consecutively enrolled. All patients with gray-scale synovitis, joint effusion, and osteophytes were examined by ultrasound for 20 hand joints. Radiographic changes in both hands were evaluated by the Kellgren-Lawrence (K-L) grading system and were described as total radiographic severity score and number of affected joints. Other measures were also assessed, including each patient’s visual analogue scale for pain, the Functional Index for Hand Osteoarthritis for functional disability, and grip and pinch strength for hand muscle strength. @*Results@#. In total, 10 patients with gray-scale synovitis, 35 with joint effusion, and 66 with osteophytes were detected in hand OA scans on ultrasound. Osteophytes on ultrasound were significantly associated with total radiographic severity score and number of affected joint (r=0.293, p=0.003 and r=0.336, p＜0.001, respectively). In addition, there were weak associations of synovitis and joint effusion with radiographic changes. Patients with higher total radiographic severity score showed larger number of ultrasound-detected abnormalities, such as synovitis, joint effusion, and osteophytes (p=0.011, p=0.002, and p＜0.001, respectively). @*Conclusion@#. This study shows that ultrasound findings, especially osteophytes, were associated with radiographic changes based on K-L grade, but not clinical and functional status in hand OA.

Clinical Usefulness of Uric Acid as a Biomarker for Knee Osteoarthritis: A Comparative Analysis With Plain Radiography and Musculoskeletal Ultrasound

OBJECTIVE: The aim of this study was to determine the relationships of serum and urine uric acid with severity or activity in knee osteoarthritis (OA).METHODS: A total of 42 patients with knee OA was enrolled, together with 58 healthy controls. Serum uric acid and spot urine uric acid levels were assessed for all patients. The severity and activity of knee OA were assessed by musculoskeletal ultrasound (MSUS) and plain radiography of the knee joint. Ultrasonographic abnormalities in knee OA includedsynovial hypertrophy, suprapatellar effusion, cartilage degradation, and osteophyte formation. Kellgren-Lawrence (K-L) grade was used to evaluate radiological progression of knee OA.RESULTS: Patients with K-L grade III had a higher urine uric acid/creatinine ratio compared to those with K-L grade I (p=0.043). Patients with synovial hypertrophy had higher serum uric acid level compared to those without synovial hypertrophy (p=0.016). The urine uric acid/creatinine ratio was higher in patients with cartilage degradation compared to those without cartilage degradation (p=0.022). Serum uric acid was significantly associated with synovial hypertrophy thickness (r=0.375, p=0.018) but not with cartilage thickness after adjusting for age and body mass index. Lower urine uric acid was related with knee OA compared to healthy controls (odds ratio=0.974, 95% confidence interval 0.954~0.994, p=0.013).CONCLUSION: The results of our study suggest that serum and urine uric acid reflects synovial inflammation based on MSUS and radiographic progression and then is associated with the pathogenesis of knee OA.

Ethanol Augments Monosodium Urate-Induced NLRP3 Inflammasome Activation via Regulation of AhR and TXNIP in Human Macrophages

Purpose@#Ethanol elicits several inflammatory responses and affects the innate immune response. The aim of this study was to identify the mechanism by which ethanol affects uric acid-induced NLR family pyrin domain-containing 3 (NLRP3) inflammasome activation by regulation of aryl hydrocarbon receptor (AhR) and thioredoxin-interacting protein (TXNIP). @*Materials and Methods@#Human myeloid leukemia cells (U937 cells) were used to assess the role of ethanol in NLRP3 inflammasome activation induced by monosodium urate (MSU) crystals. Expression of target molecules, such as NLRP3 inflammasome components, AhR, and TXNIP, were measured using quantitative real-time PCR and Western blot analyses. The effect of ethanolinduced TXNIP on the NLRP3 inflammasome was assessed in human macrophages transfected with TXNIP siRNA. @*Results@#U937 cells treated with 100 mM ethanol for 24 h induced NLRP3 and interleukin (IL)-1β expression. Ethanol increased reactive oxygen species generation in a time- and dose-dependent manner. AhR mRNA expression was downregulated in U937 cells treated with 100 mM ethanol, whereas CYP1A1 mRNA expression increased. Treatment with ethanol increased NLRP3 and IL-1β mRNA and protein expression in U937 cells exposed to 1.0 mg/mL of MSU crystals for 24 h. TXNIP expression in U937 cells incubated with both 100 mM ethanol and 1.0 mg/mL of MSU crystals was significantly higher than in cells incubated with MSU crystals alone. Treatment with 100mM ethanol for 24 h downregulated NLRP3 and IL-1β expression in MSU crystal-activated U937 cells transfected with TXNIP siRNA, compared to those with scramble siRNA. @*Conclusion@#Ethanol stimulates uric acid-induced NLRP3 inflammasome activation through regression of AhR and upregulation of TXNIP.

Anti-Sm Antibody, Damage Index, and Corticosteroid Use Are Associated with Cardiac Involvement in Systemic Lupus Erythematosus: Data from a Prospective Registry Study

Background@#Disease-specific factors that predispose patients to diverse cardiac diseases in systemic lupus erythematosus (SLE) have been established. The aim of this study was to identify risk factors for cardiac involvement in patients with SLE drawn from the Korean Lupus Network (KORNET) registry. @*Methods@#A total of 437 patients with SLE recruited from the KORNET registry were included in the analysis. The Cox proportional hazard model was used to identify risk factors for the development of cardiac involvement during the follow-up period. The hazard ratios for risk factors of cardiac involvement were assessed using Kaplan-Meier curves and log-rank test. @*Results@#Of 437 patients with SLE, 12 patients (2.7%) developed new cardiac involvement during a median follow-up period of 47.6 months. Frequencies in men and in patients with anti-Sm antibody, anti-Ro antibody, and at least one Systemic Lupus International Collaborating Clinics/American College of Rheumatology damage index (SDI) score in patients with cardiac involvement were higher, compared to those without cardiac involvement (P < 0.001, P = 0.026, P = 0.015, and P < 0.001, respectively). Men gender, older age, anti-Sm antibody, SDI, and corticosteroid dosage were potent predictors for cardiac involvement in patients with SLE in the determination of risk factors for cardiac involvement. Men, anti-Sm antibody positivity, and SDI ≥ 1 increased incidence rates of cardiac involvement for (P < 0.001, P = 0.036, and P < 0.001, respectively). @*Conclusion@#The results of this study reveal that SLE-related factors such as anti-Sm antibody, SDI, and corticosteroid dosage at baseline are risk factors for cardiac involvement in SLE.

Erratum: Clinical Usefulness of Uric Acid as a Biomarker for Knee Osteoarthritis: A Comparative Analysis With Plain Radiography and Musculoskeletal Ultrasound

The original version of this article contained a typographical error in the Abstract, Main text, and Figure 1. These errors have now been corrected in the online version of the Article.

Korean rheumatology workforce from 1992 to 2015: current status and future demand

BACKGROUND/AIMS@#Rheumatology in Korea has rapidly advanced in the 24 years since the subspecialty board certification program was established in 1992. The objective of this investigation was to analyze the distribution of rheumatology practices in Korea in order to better understand the rheumatology workforce.@*METHODS@#Using a membership list from the Korean College of Rheumatology (KCR), we obtained information on practicing rheumatologists. We mapped the ratio of rheumatologists to the general population and to patients with rheumatologic disease using data from Statistics Korea and the 2015 Health Insurance Review & Assessment Service (HIRA).@*RESULTS@#In the 16 administrative districts of Korea in 2015, there were 311 practicing rheumatologists on the list of KCR members. There were 218 members practicing in metropolitan areas and 93 members in the provinces. The mean number of rheumatologists per 100,000 people was 0.60, with 0.33/100,000 in the provinces, but 0.92/100,000 in metropolitan areas, a 2.7-fold difference. The number of rheumatologists per 100,000 patients with chronic rheumatic disease was 17.21 in metropolitan areas but 6.57 in the provinces, according to 2015 HIRA data. This geographic maldistribution emerged as a problem; indeed, the regional disparity in the distribution of Korean rheumatologists was striking when compared to the published medical professional distribution in 2014.@*CONCLUSIONS@#Because of the uneven distribution of rheumatologists, it is likely that some patients with chronic rheumatic conditions have limited access to rheumatology care. Thus, a policy-based approach is needed to alleviate this disparity.

The Effect of Mycophenolate Mofetil on Non-Renal Manifestations in Systemic Lupus Erythematosus: Results from Korean Lupus Network Registry

BACKGROUND: The objective of this study was to identify the effects of mycophenolate mofetil (MMF) on non-renal manifestations in systemic lupus erythematosus (SLE). METHODS: The study population comprised 439 SLE patients from the Korean Lupus Network registry who were followed up annually and completed the baseline survey and two follow-up visits from 2014 to 2018. Disease activity, laboratory markers, and clinical manifestations including mucocutaneous lesions, arthritis, serositis, neurological disorders, and hematologic/immunologic abnormalities were assessed. All variables by group (MMF and non-MMF) effects with time (baseline, 1st follow-up, and 2nd follow-up) were analyzed by generalized estimation equation. RESULTS: Seventy-two patients were treated with MMF. There was significant difference in frequencies of malar rash, arthritis, renal disorder, and hematologic disorder between MMF and non-MMF groups in total SLE patients. In subgroup analysis of hematologic abnormalities in total patients, frequency of leukopenia was significantly different between the two groups during follow-up (P = 0.001), but frequencies of hemolytic anemia, lymphopenia, and thrombocytopenia were not. In addition, frequencies of leukopenia in patients without lupus nephritis were significantly decreased in MMF group compared to non-MMF group (P = 0.012). CONCLUSION: This study showed that MMF might be a beneficial treatment for hematologic abnormalities, especially leukopenia, in SLE.

Interrelationship of Uric Acid, Gout, and Metabolic Syndrome: Focus on Hypertension, Cardiovascular Disease, and Insulin Resistance

The mean serum uric acid level and the prevalence of hyperuricemia have increased over the past few decades. Hyperuricemia is considered to be responsible for the increased risk of hypertension, insulin resistance, and cardiovascular disease. Metabolic syndrome also contributes to the development of type II diabetes mellitus and cardiovascular disease. Despite the close relationships between uric acid and the components of metabolic syndrome, the causal effect of uric acid on these clinical issues is unclear. Recent studies have revealed the possible development of metabolic syndrome mediated by fructose-induced hyperuricemia. This review summarizes the available clinical and experimental data supporting the causal effect of uric acid on the components of metabolic syndrome, including hypertension, cardiovascular disease, and insulin resistance.

Gender Is a Risk Factor for Annual Decline in Estimated Glomerular Filtration Rate in Patients Treated with Biological DMARDs in Rheumatoid Arthritis and Ankylosing Spondylitis: a Retrospective Observational Study

BACKGROUND: This study identified the risk factors of changes in renal function in patients with rheumatoid arthritis (RA) and ankylosing spondylitis (AS) treated with biological disease-modifying anti-rheumatic drugs (bDMARDs). METHODS: We retrospectively enrolled patients with RA (n = 293) and AS (n = 125) treated with bDMARDs. The estimated glomerular filter rate (eGFR) using the Modification of Diet in Renal Disease equation was applied for assessment of annual changes in renal function between initiation and last visit after bDMARD therapy. The annual change in eGFR was used as an indicator for change in renal function. Statistical significance was assessed by Mann-Whitney test, Spearman's correlation coefficient, and multivariate linear regression analysis. RESULTS: The positive annual change in eGFR in women was significantly noted, compared to that in men (P = 0.004). The annual change in eGFR was different between men and women (P = 0.038) in RA, but not in AS patients (P = 0.126). In multivariate linear regression analysis, women patients and increased serum creatinine at baseline were closely associated with positive annual change in eGFR in both RA and AS patients. In RA patients, younger age and lower ESR level were considered risk factors of positive annual change in eGFR (P = 0.013 and P = 0.022, respectively). However, disease duration and duration of bDMARD use were not associated with annual change in eGFR. CONCLUSION: This study found that gender, especially men, might be responsible for annual decline in eGFR in RA and AS patients treated with bDMARDs.

Self-Reported Physical Activity Is Associated with Lupus Nephritis in Systemic Lupus Erythematosus: Data from KORean Lupus Network (KORNET) Registry

PURPOSE: The aim of this study was to identify the associations among physical activity, disease activity, and organ damage in patients with systemic lupus erythematosus (SLE). MATERIALS AND METHODS: A total of 415 patients with SLE were consecutively enrolled from the KORean lupus Network (KORNET) registry. This registry assessed clinical features, disease activity [Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K)], and organ damage [Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) Damage Index (SDI)] upon enrollment in the study. Self-reported physical activity was measured by the International Physical Activity Questionnaire. Statistical analyses were conducted using the Mann-Whitney U test and multivariate logistic regression analysis. RESULTS: A significant difference in vigorous activity was noted between patients with lupus nephritis (LN) (n=93) and those without LN (n=322) (p=0.012), but not in moderate and walking activities. In contrast, no differences in physical activity, walking, moderate, and vigorous intensity, according to SLEDAI-2K and SDI were found. In addition to younger age (p=0.032), high physical component summary of SF-36 (p=0.004) and SLEDAI-2K (p=0.038), and less vigorous physical activity were associated with LN (p=0.024). However, cardiovascular disease was not associated with physical activity in SLE patients. CONCLUSION: This study showed that patients with LN had less vigorous physical activity than patients without LN. The results suggest that lupus nephritis might be associated with physical activity.

Impact of early diagnosis on functional disability in rheumatoid arthritis

BACKGROUND/AIMS: To determine whether early diagnosis is beneficial for functional status of various disease durations in rheumatoid arthritis (RA) patients. METHODS: A total of 4,540 RA patients were enrolled as part of the Korean Observational Study Network for Arthritis (KORONA). We defined early diagnosis as a lag time between symptom onset and RA diagnosis of ≤ 12 months, whereas patients with a longer lag time comprised the delayed diagnosis group. Demographic characteristics and outcomes were compared between early and delayed diagnosis groups. Logistic regression analyses were performed to identify the impact of early diagnosis on the development of functional disability in RA patients. RESULTS: A total of 2,597 patients (57.2%) were included in the early diagnosis group. The average Health Assessment Questionnaire-Disability Index (HAQ-DI) score was higher in the delayed diagnosis group (0.64 ± 0.63 vs. 0.70 ± 0.66, p < 0.01), and the proportion of patients with no functional disability (HAQ = 0) was higher in the early diagnosis group (22.9% vs. 20.0%, p = 0.02). In multivariable analyses, early diagnosis was independently associated with no functional disability (odds ratio [OR], 1.19; 95% confidence interval [CI], 1.01 to 1.40). In a subgroup analysis according to disease duration, early diagnosis was associated with no functional disability in patients with disease duration < 5 years (OR, 1.37; 95% CI, 1.09 to 1.72) but not in patients with longer disease duration (for 5 to 10 years: OR, 1.07; 95% CI, 0.75 to 1.52; for ≥ 10 years: OR, 0.92; 95% CI, 0.65 to 1.28). CONCLUSIONS: Early diagnosis is associated with no functional disability, especially in patients with shorter disease duration.

Genetic Association for P2X7R rs3751142 and CARD8 rs2043211 Polymorphisms for Susceptibility of Gout in Korean Men: Multi-Center Study

The aim of this study was to determine the association between P2X7R rs3751142 and CARD8 rs2043211 polymorphisms and gout susceptibility in male Korean subjects. This study enrolled a total of 242 male patients with gout and 280 healthy controls. The polymorphisms of two individual genes including rs3751142(C>A) in the P2X7R gene and rs2043211(A>T) in the CARD8 gene were assessed using Taq-Man analysis. Statistical analyses were performed using the Chi-square test, Kruskal-Wallis test, and logistic regression analyses. A difference in genotypic frequency of the P2X7R rs3751142 and CARD8 rs2043211 genes was not detected between gout and control patients. Clinical parameters including age, onset age, disease duration, body mass index, and serum uric acid levels were not different among the three genotypes for either P2X7R or CARD8 (P > 0.05 for all). A pair-wise comparison of P2X7R rs3751142 and CARD8 rs2043211 genotype combinations revealed that subjects with the CA P2X7R rs3751142 genotype and the TT CARD8 rs2043211 genotype had a trend toward a higher risk of gout compared to the CC/AA combination (P = 0.056, OR = 2.618, 95% CI 0.975 - 7.031). In conclusion, this study revealed that genetic variability of the P2X7R rs3751142 and CARD8 rs2043211 genes might, in part, be associated with susceptibility for gout.