Performance of cut-offs adjusted with positive control band intensity in line-blot assays for myositis-specific antibodies.

The diagnostic performance of band intensity (BI) cut-offs, adjusted by a positive control band (PCB) in a line-blot assay (LBA) for myositis-related autoantibodies (MRAs) is investigated. Sera from 153 idiopathic inflammatory myositis (IIM) patients with available immunoprecipitation assay (IPA) data and 79 healthy controls were tested using the EUROLINE panel. Strips were evaluated for BI using the EUROLineScan software, and the coefficient of variation (CV) was calculated. Sensitivity and specificity, area under the curve (AUC), and the Youden's index (YI) were estimated at non-adjusted or PCB-adjusted cut-off values. Kappa statistics were calculated for IPA and LBA. Although inter-assay CV for PCB BI was 3.9%, CV was 12.9% in all samples, and a significant correlation was found between BIs of PCB and seven MRAs (all P < 0.05). At adjusted BI (aBI) > 10, the negative conversion rate of myositis-specific autoantibody (MSA)-positivity at BI > 10 was 11.5% in controls and 1.3% in patients. The specificity, AUC, and YI for MSAs at aBI > 10 or > 20 were higher than those at non-adjusted cut-off values. Additionally, AUC (0.720), YI (0.440), and the prevalence of MRAs with kappa > 0.60 (58.3%) were the highest at aBI > 20. The overall sensitivity and specificity for MSAs were 50.3% and 93.7% at aBI > 20, respectively, and 59.5% and 65.8% with BI > 10, respectively. The diagnostic performance of LBA can be improved using PCB-adjusted BIs. aBI > 20 is the optimal cut-off for IIM diagnosis using the EUROLINE LBA panel.

Metabolic obesity and the risk of knee osteoarthritis progression in elderly community residents: A 3-year longitudinal cohort study.

OBJECTIVE: Metabolic syndrome is a major health problem worldwide associated with obesity, thus drawing attention to its relation to osteoarthritis (OA). However, it is still uncertain whether metabolic syndrome or body fat distribution is associated with knee OA. The aim of this longitudinal study was to elucidate the association between metabolic obesity and adverse structural changes of knee OA assessed by magnetic resonance imaging (MRI). METHODS: Participants were recruited from the Hallym Aging Study cohort in Korea. Knee MRI scans, along with dual-energy X-ray absorptiometry, were assessed in 226 participants at baseline and after 3 years. The structural progression in the tibiofemoral joint was evaluated using the semi-quantitative Whole-Organ MRI Score (WORMS) for cartilage morphology and bone marrow lesions (BML). Logistic regression with generalized estimating equation was performed for associations of metabolic risk factors with worsening of WORMS scores at the subregional level. RESULTS: In the medial compartment, fat mass in women was associated with cartilage loss, but the statistical significance disappeared after adjusting for body mass index. Metabolic syndrome and each of its components were not associated with cartilage loss or increase of BML. On the other hand, the interaction effects of metabolic syndrome on the association between obesity and knee OA progression were not significant. CONCLUSION: In this cohort, metabolic effects of obesity on knee cartilage damage and BML were not demonstrated. Further large-scale studies are required to prove the causal relationship between metabolic obesity and knee OA.

Norepinephrine modulates IL-1ß-induced catabolic response of human chondrocytes.

BACKGROUND: The influence of the sympathetic nervous system (SNS) on metabolism of bone and cartilage expressing ß-adrenergic receptors (AR) was suggested. Here, we investigated whether the SNS functions as a modulator of cartilage metabolism induced by interleukin-1beta (IL-1ß). METHODS: Human articular chondrocytes and articular cartilage were collected from patients with osteoarthritis (OA). Chondrocyte monolayer and cartilage explant culture were stimulated with IL-1ß. The activity of ß-ARs was modulated by an agonist, norepinephrine (NE), and antagonists, including propranolol, atenolol, nebivolol, and nadolol. RESULTS: The levels of ß1-, ß2-, and ß3-AR in OA cartilage and IL-1ß-treated chondrocytes were lower than normal cartilage and untreated cells. Treatment of chondrocytes with IL-1ß and ß-blockers, including propranolol, atenolol, nebivolol, and nadolol, for 6 h significantly upregulated IL-1ß-induced expression of MMP-1, -3, and - 13, compared to chondrocytes treated with IL-1ß alone, indicating that antagonism of ß-AR confers catabolic signals. On the other hand, NE antagonized IL-1ß-induced catabolic response. In addition, NE significantly inhibited IL-1ß-induced release of glycosaminoglycan (GAG) from cartilage explant culture. In addition, ß-AR activity significantly affected IL-1ß-stimulated phosphorylation of JNK and ERK. These results indicate that ß-AR signal is associated with cartilage metabolism. CONCLUSIONS: Our findings showed that ß-ARs is a regulator of cartilage catabolism induced with IL-1ß.

Serum uric acid and knee osteoarthritis in community residents without gout: a longitudinal study.

OBJECTIVES: Emerging evidence suggests a potential link between OA and gout; however, the association between serum uric acid (UA) itself and knee OA remains uncertain due to a lack of longitudinal studies. Here, we investigated the association between serum UA and knee OA according to cartilage status in elderly community residents without gout. METHODS: In this longitudinal study, participants without a history of gout were recruited from among the Korean cohort of the Hallym Aging Study (n = 296 for radiography study and n = 223 for MRI study). Weight-bearing knee radiographs and 1.5-T MRI scans, along with blood collection for analysis of serum UA, were performed at baseline and after 3 years. The severity and structural progression of knee OA were evaluated using the Kellgren-Lawrence grading system and the Whole-Organ MRI Score (WORMS) cartilage scoring method. Multivariable logistic regression analysis was conducted using generalized estimating equation (GEE) models. RESULTS: Serum UA levels were not associated with radiographic progression after adjusting for age, sex and BMI. There was no significant association between serum UA and tibiofemoral cartilage loss on MRI. However, baseline serum UA levels were negatively associated with patellofemoral cartilage loss over 3 years (adjusted odd ratio 0.70 per 1 mg/dl increase, 95% CI: 0.49, 0.98). CONCLUSION: In this population-based cohort, serum UA was not a risk factor for knee OA progression. Further large-scale longitudinal studies in other populations are needed to validate the effects of UA on cartilage damage.

Potential clinical utility of a novel optical tomographic imaging for the quantitative assessment of hand rheumatoid arthritis.

Optical tomographic imaging (OTI) was reported to be a novel technique for the early diagnosis and disease activity assessment of rheumatoid arthritis (RA). This study aimed to evaluate the clinical utility of OTI for the detection of hand synovitis of RA patients. Manu-scan was used to perform imaging targeting the proximal interphalangeal (PIP) and metacarpophalangeal (MCP) joints in 12 RA patients and three controls. The enrolled RA patients also underwent magnetic resonance imaging (MRI) and bone scintigraphy (BS) to provide reference images. Of the 181 joints feasible for OTI analysis, 140 joints (111 in RA patients and 29 in controls, 77.3%) in which the difference of the OTI indices in the two measurements was within 20% were evaluated. The OTI indices in RA joints were significantly lower than those in control joints (p < 0.001). Overall, the OTI indices in RA joints decreased as the synovitis grades on MRI or BS increased. Moreover, OTI was able to discriminate between RA and control joints (AUC = 0.815, 95% CI 0.739-0.891), even if RA joints were normal on physical examination (AUC = 0.714, 95% CI 0.594-0.834). OTI was in good agreement (kappa = 0.60) with MRI for evaluating synovitis in RA patients and showed positive results in 11.4% of clinically asymptomatic joints. OTI in this study showed the potential to be a supplementary imaging modality for the quantification of synovial inflammation in PIP and MCP joints of RA patients. Further large-scale trials are needed to confirm these findings.

Novel susceptibility alleles in HLA region for myositis and myositis specific autoantibodies in Korean patients.

OBJECTIVES: HLA genes are a major genetic risk factor for myositis and myositis specific antibodies (MSAs), exhibiting unique HLA backgrounds for myositis in different ethnic groups. This is the first large scale Korean study to genotype the HLA-DRB1 and -DPB1 alleles and to examine their association with myositis and MSAs. METHODS: HLA-DRB1 and HLA-DPB1 alleles and MSAs were examined in 179 patients with dermatomyositis (DM, n = 129) or polymyositis (PM, n = 50) and healthy controls (n = 800 for HLA-DRB1, n = 548 for HLA-DPB1). Associations between individual HLA alleles and myositis/MSA were examined. Bonferroni correction was applied for multiple testing comparing patients and controls. RESULTS: A total of 33 HLA-DRB1 and 24 HLA-DPB1 alleles were genotyped in patients and controls. MSAs were found in 67.0% of patients. Anti-MDA5 (26.8%) and anti-aminoacyl-tRNA synthetase antibodies (15.6%) were most common, followed by anti-Mi2 (9.5%) and anti-TIF1γ antibodies (8.9%). HLA-DRB1*12:02 and HLA-DRB1*14:03 were associated with DM and PM, respectively. HLA-DRB1*12:02 was associated with anti-MDA5, HLA-DRB1*08:03 with anti-ARS, HLA-DRB1*14:03 with anti-SRP, and HLA-DRB1*07:01 with anti-Mi2 antibodies. Although HLA-DRB1*13:01 was associated with anti-TIF1γ antibodies, the frequency of HLA-DRB1*13:01 was rare. HLA-DPB1*02:01 was negatively associated with myositis and PM while HLA-DPB1*17:01 was associated with anti-Mi2 positive DM. CONCLUSIONS: Unique immunogenetic background was observed for Korean patients with myositis. Novel myositis susceptibility alleles, HLA-DRB1*12:02 and HLA-DRB1*14:03, were identified, together with MSA-associated HLA alleles unique to Korean patients with myositis.

Baseline peripheral blood neutrophil-to-lymphocyte ratio could predict survival in patients with adult polymyositis and dermatomyositis: A retrospective observational study.

Recent studies have suggested that neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein-to-albumin ratio (CAR) are emerging markers of disease activity and prognosis in patients with chronic inflammatory diseases, cardiovascular diseases, or malignancies. Therefore, we investigated the clinical significance and prognostic value of the NLR and CAR in adult patients with polymyositis and dermatomyositis. The medical records of 197 patients with newly diagnosed polymyositis/dermatomyositis between August 2003 and November 2016 were retrospectively reviewed. Survival and causes of death were recorded during an average 33-month observational period. Clinical and laboratory findings were compared between survivors and non-survivors. Using receiver operating characteristic curves, the NLR and CAR cut-off values for predicting survival were calculated. Univariate and multivariate analyses using Cox proportional hazard models were performed to identify factors associated with survival. Twenty-six patients (13.2%) died during the study period, and the 5-year survival-rate was estimated to be 82%. The non-survivor group exhibited older age and a higher prevalence of interstitial lung disease (ILD), acute interstitial pneumonia, and acute exacerbation of ILD compared to that in the survivor group. NLR and CAR values were significantly higher in the non-survivors and in patients with polymyositis/dermatomyositis-associated ILD, and the death rates increased across NLR and CAR quartiles. Furthermore, when stratified according to the NLR or CAR optimal cut-off values, patients with a high NLR (>4.775) or high CAR (>0.0735) had a significantly lower survival rate than patients with low NLR or CAR, respectively. In addition, old age (>50 years), the presence of acute interstitial pneumonia, hypoproteinemia (serum protein <5.5 g/dL), and high NLR (but not high CAR) were independent predictors for mortality. The results indicate that a high NLR is independently associated with worse overall survival. Thus, the baseline NLR level may be a simple, cost-effective prognostic marker in patients with polymyositis/dermatomyositis.

Modeling quality of life in patients with rheumatic diseases: the role of pain catastrophizing, fear-avoidance beliefs, physical disability, and depression.

PURPOSE: To examine factors in the fear-avoidance model, such as pain, pain catastrophizing, fear-avoidance beliefs, physical disability, and depression and their relationships with physical and psychological quality of life in patients with rheumatic diseases. MATERIALS AND METHODS: The data were obtained from 360 patients with rheumatic diseases who completed self-report measures assessing study variables. Structural equation modeling was used to examine the hypothesized relationships among factors specified in the fear-avoidance model predicting physical and psychological quality of life. RESULTS: Final models fit the data well, explaining 96% and 82% of the variance in physical and psychological quality of life, respectively. Higher pain catastrophizing was related to stronger fear-avoidance beliefs that had a direct negative association with physical disability and depression, which, in turn, negatively affected physical quality of life. Pain severity was also directly related to physical disability. Physical disability also affected physical quality of life indirectly through depression. The hypothesized relationships specified in the model were also confirmed for psychological quality of life. However, physical disability had an indirect association with psychological quality of life via depression. CONCLUSION: The current results underscore the significant role of cognitive, affective, and behavioral factors in perceived physical disability and their mediated detrimental effect on physical and psychological quality of life in patients with rheumatic diseases. Implications for rehabilitation The fear-avoidance model is applicable to the prediction of quality of life in patients with rheumatic diseases. As pain-catastrophizing and fear-avoidance beliefs are important factors linked to physical disability and depression, intervening these cognitive factors is necessary to improve physical function and depression in patients with rheumatic diseases. Considering the strong association between depression and physical and psychological quality of life, the assessment and treatment of the former should be included in the rehabilitation of patients with rheumatic diseases. Interventions targeting physical function and depression are likely to be effective in terms of improving physical and psychological quality of life in patients with rheumatic diseases.

Pivotal factors for successful withdrawal of nonsteroidal anti-inflammatory drugs in rheumatoid arthritis patients in remission or with low-disease activity.

The purpose of this study is to examine the patient-reported outcomes (PRO) after discontinuing nonsteroidal anti-inflammatory drugs (NSAIDs) and clinical factors associated with a favorable outcome in patients with rheumatoid arthritis (RA) in remission or with low-disease activity (LDA). A 16-week prospective open-label trial was conducted at eight rheumatology clinics in Korea. RA patients with 28-joint disease activity score based on erythrocyte sedimentation rate (DAS28-ESR) < 3.2 who were on NSAIDs for more than a month were enrolled, and NSAIDs were discontinued. Acetaminophen (AAP) was used as the rescue medication, and NSAIDs were restarted when joint pain was intolerable with AAP. The endpoint was to analyze the group of patients who continued to withdraw NSAIDs. Among 109 enrolled patients, 105 completed the 16-week follow-up. Eighty-nine (84.8%) patients remained without restarting NSAIDs. In these patients, there was a slight increase in their pain levels compared with baseline (median 14.0 versus 19.0 using the pain-visual analog scale, p = 0.010). However, changes in DAS28-ESR (p = 0.638) and routine assessment of patient index data 3 (RAPID-3) (p = 0.128) were insignificant. Moreover, 66 (62.9%) patients showed sustained effectiveness on PRO without restarting NSAIDs. In the multivariate regression models, joint swelling was the detrimental factor in NSAID withdrawal (odds ratio [OR] 0.149, 95% confidence interval [CI] 0.033-0.680, p = 0.014) and sustained effectiveness (OR 0.284, 95% CI 0.091-0.883, p = 0.030). Joint pain in RA patients in remission or with LDA can be well managed without NSAIDs, especially in those without swollen joints at the time of cessation.

Examining the Relationship Between Pain Catastrophizing and Suicide Risk in Patients with Rheumatic Disease: the Mediating Role of Depression, Perceived Social Support, and Perceived Burdensomeness.

PURPOSE: Little research has examined the role of pain catastrophizing (PC) in predicting suicide among patients with rheumatic disease or the mechanisms through which it works. This study examines whether depression, perceived social support (PSS), and perceived burdensomeness (PB) mediate the relationship between PC and suicide risk. It also examines the relative importance of sociodemographic, clinical, and psychological factors in predicting suicide risk. METHODS: Three hundred sixty patients from a rheumatology clinic in Korea completed measures of pain catastrophizing, social support, depression, and perceived burdensomeness. RESULTS: In hierarchical multiple regression analysis, the PC magnification, PB, physical disability, and PSS were significantly related to suicide risk. Results of the serial multiple mediation analysis indicated that the total indirect effect of PC magnification on suicide risk was significant while the direct effect was not. Four specific indirect effects of PC magnification were found to be statistically significant. First of all, PC magnification was associated with suicide risk through PB and through depression and PB. PC magnification was also associated with suicide risk through depression and PSS. Lastly, PC magnification was associated with suicide risk through depression, PSS, and PB. CONCLUSIONS: The identified pathways through which PC affects suicide risk suggest the importance of depression, PSS, and PB. Evaluation and intervention targeted at physical disability and the psychological factors of PC magnification, depression, PSS, and PB may be integrated into the management of suicide risk in patients with rheumatic disease.

Elevated Erythrocyte Sedimentation Rate Is Predictive of Interstitial Lung Disease and Mortality in Dermatomyositis: a Korean Retrospective Cohort Study.

Interstitial lung disease (ILD) is a major cause of death in patients with dermatomyositis (DM). This study was aimed to examine the utility of the erythrocyte sedimentation rate (ESR) as a predictor of ILD and prognostic marker of mortality in patients with DM. One hundred-and-fourteen patients with DM were examined, including 28 with clinically amyopathic DM (CADM). A diagnosis of ILD was made based on high resolution computed tomography (HRCT) scans. The association between elevated ESR and pulmonary impairment and mortality was then examined. ILD was diagnosed in 53 (46.5%) of 114 DM patients. Cancer was diagnosed in 2 (3.8%) of 53 DM patients with ILD and in 24 (92.3%) of those without ILD (P < 0.001). The median ESR (50.0 mm/hour) in patients with ILD was significantly higher than that in patients without ILD (29.0 mm/hour; P < 0.001). ESR was inversely correlated with forced vital capacity (Spearman ρ = - 0.303; P = 0.007) and carbon monoxide diffusing capacity (ρ = - 0.319; P = 0.006). DM patients with baseline ESR ≥ 30 mm/hour had significantly higher mortality than those with ESR < 30 mm/hour (P = 0.002, log-rank test). Patients with a persistently high ESR despite immunosuppressive therapy was associated with higher mortality than those with a normalized ESR (P = 0.039, log-rank test). Elevated ESR is associated with increased mortality in patients with DM due to respiratory failure. Thus, monitoring ESR should be an integral part of the clinical care of DM patients.

Survival benefit associated with early cyclosporine treatment for dermatomyositis-associated interstitial lung disease.

Interstitial lung disease (ILD) is the most common cause of death in dermatomyositis (DM). Cyclosporine A (CsA) has shown to be effective in DM-associated ILD (DM-ILD). This study aimed to define the optimal time of CsA administration. A total of 47 patients with DM-ILD, who were treated with CsA at Seoul National University Hospital between January 1998 and June 2013, were enrolled. ILD was diagnosed based on typical chest high-resolution computed tomography (HRCT) findings. Patients with early and delayed CsA treatment were compared in regard to the mortality and ILD progression on HRCT. The early (n = 16) and the delayed treatment group (n = 31) did not differ in regard to baseline clinical characteristics including HRCT scores and pulmonary function. Patients with clinically amyopathic DM (CADM) were more common in the early treatment group. The mortality rate was significantly lower in the early treatment group than in the delayed treatment group (p = 0.009). The survival benefit of early CsA treatment remained significant even after adjusting for age, degree of dyspnea, CADM status, and the year of CsA treatment (hazard ratio 0.057, 95 % confidence interval 0.007-0.472). CsA stabilized disease progression on HRCT in the early treatment group (p = 0.738). Delay in CsA treatment is associated with a worse survival in patients with DM-ILD. Early CsA treatment should be considered at DM-ILD diagnosis especially in patients at a higher risk of developing a rapidly progressive ILD.

A decision model for the watch-and-wait strategy in systemic sclerosis-associated interstitial lung disease.

OBJECTIVE: To develop a decision model to identify SSc-associated interstitial lung disease (ILD) patients who are eligible for watchful waiting at ILD diagnosis. METHODS: One hundred and fifty-one SSc-ILD patients who received medical care at Seoul National University Hospital from 1986 to 2013 were enrolled in this retrospective cohort study. ILD was diagnosed by chest CT. Patients with and without immunosuppressive treatment were compared in terms of characteristics at ILD diagnosis to identify distinguishing variables. After multivariate analysis, a decision model for watchful waiting was formulated. Its validity was assessed by comparing the survival of patients whose management in real practice did and did not accord with the management recommended by the model. RESULTS: The untreated group had better survival than the immunosuppressive treatment group (P = 0.0316, by log-rank test). The untreated group was less likely to have gastrointestinal involvement (P = 0.008) and pulmonary arterial hypertension (PAH), as determined by echocardiography) (P = 0.015) and more likely to have favourable initial forced vital capacity (P = 0.0004), favourable initial lung diffusion capacity for carbon monoxide (P = 0.0002) and a low CT grade (P < 0.001). The final watchful waiting decision model included lack of PAH and limited ILD extent on CT. Application of the model to the cohort revealed that patients who were eligible for watchful waiting (as determined by the model) and underwent this management strategy had better survival than eligible patients who underwent immunosuppressive treatment (P = 0.048, by log-rank test). CONCLUSION: Watchful waiting may be effective for SSc-ILD patients who have minimal pulmonary involvement on CT and lack PAH on echocardiography at baseline.