Geriatric nutrition risk index: a more powerful index identifying muscle mass loss in patients with rheumatoid arthritis.

OBJECTIVE: To explore the association of geriatric nutrition risk index (GNRI), a traditional albumin-body weight calculation, with myopenia in patients with rheumatoid arthritis (RA) and compare its ability to identify myopenia with protein indicators. METHODS: This cross-sectional study was carried out based on a Chinese RA cohort. Clinical data and protein indicators (including albumin, globulin, albumin to globulin ratio, prealbumin, hemoglobin) were collected. GNRI was estimated by serum albumin and body weight. Myopenia was indicated as muscle mass loss measured by bioelectric impedance analysis. RESULTS: There were 789 RA patients included with mean age 52.6 ± 12.6 years and 77.6% female. There were 41.3%, 18.0%, 27.5%, 13.2% patients with no (GNRI > 98), low (GNRI 92 to ≤ 98), moderate (GNRI 82 to < 92), and major nutrition-related risk (GNRI < 82). There were 406 (51.5%) RA patients with myopenia, RA patients with major nutrition-related risk had the highest prevalence of myopenia (87.5% vs. 73.3% vs. 50.0% vs. 26.1%). Multivariate logistic analysis showed that compared with no risk, RA patients with low (OR = 3.23, 95% CI: 1.86-5.61), moderate (OR = 9.56, 95% CI: 5.70-16.01), and major nutrition-related risk (OR = 28.91, 95% CI: 13.54-61.71) were associated with higher prevalence of myopenia. Receiver operating characteristic curves showed that GNRI (AUC = 0.79) performed a better identifiable ability toward myopenia than serum albumin (AUC = 0.66) or others indicators (AUC range 0.59 to 0.65), respectively. CONCLUSION: GNRI, an objective and convenient albumin-weight index, may be preferable for identifying myopenia in RA patients. Key Points • We firstly elucidated the association of GNRI with muscle mass loss among RA patients, and compared its ability to identify muscle mass loss with serum albumin or other protein indicators. • Major nutrition-related risk identified by GNRI showed the highest risk of muscle mass loss, GNRI demonstrated a greater ability to identify myopenia in RA patients. which indicated GNRI was an objective and convenient albumin-weight index to identify myopenia in RA patients.

Association of serum concentrations of remnant cholesterol with incident cardiovascular disease in patients with rheumatoid arthritis: A real-world data from 2001 to 2022.

BACKGROUND: Remnant cholesterol (RC) promotes cardiovascular disease (CVD) in the general population, but its role among rheumatoid arthritis (RA) patients remains unknown. We aimed to investigate circulating RC levels associated with incident CVD among Chinese patients with RA. METHODS: A total of 1018 RA patients free of baseline CVD were included and followed up in a prospective RA CVD cohort from 2001 to 2022. Fasting serum levels of triglycerides, total cholesterol (TC), low-density (LDL-C), and high-density lipoprotein cholesterol (HDL-C) were measured, while RC and Non-HDL-C levels were calculated. The primary exposure was RC levels. A LASSO Cox model was used to select covariates. The Fine-Gray competing risk model was used to estimate hazard ratios (HRs). RESULTS: RA patients had a mean age of 53.9 years, and 802 (78.8%) were females. After a median follow-up of 5.54 years, 131 patients developed CVD with an incidence rate of 21.6 per 1000 person-years. Continuous and quartile-categorized RC levels were associated with incident CVD before and after multivariate adjustment and Bonferroni correction (all P < 0.001). There were no robust associations of other lipids with incident CVD. The fully adjusted HRs for RC were 2.30 (95% CI 1.58-3.35) per 1 mmol/L increase, and 2.40 (1.36-4.25) and 2.81 (1.60-4.94) for patients in the 3rd and 4th versus the 1st quartile, respectively. CONCLUSIONS: Circulating RC levels are positively associated with incident CVD among Chinese RA patients independent of known risk factors, implying its clinically preferable use for improving the stratification of CVD risk in RA patients.

Muscle mass loss is associated with physical dysfunction in patients with early rheumatoid arthritis.

Background: Muscle mass loss is common in long-standing rheumatoid arthritis (RA). The aim was to explore the prevalence and effects of RA disease characteristics in patients with early RA. Methods: This cross-sectional study was carried out based on a Chinese RA cohort and control subjects. The body composition (BC) was assessed using bioelectric impedance analysis. Myopenia was defined by an appendicular skeletal muscle mass index of ≤ 7.0 kg/m2 in men and ≤ 5.7 kg/m2 in women. Physical dysfunction was defined as a health assessment questionnaire disability index > 1. Propensity score matching was performed to balance age and gender differences among patients with early RA (disease duration ≤ 12 months) and established RA, and controls (with 1:3:3 matching). Results: In total, 2017 controls and 1,008 patients with RA were recruited for this study. Among the patients with RA, there were 190 (18.8%) patients with early RA, with a median disease duration of 7 (4, 11) months. The matched patients with early RA (n = 160) showed a higher prevalence of myopenia than the matched controls (41.3 vs. 15.8%, P < 0.0167), but no difference was found in the matched patients with established RA (41.3 vs. 50.4%, P > 0.0167). Compared with the patients with established RA, the patients with early RA exhibited higher disease activity scores [disease activity score in 28 joints with four variables including C-reactive protein (DAS28-CRP): median 4.76 vs. 3.93, P < 0.001] and a higher prevalence of physical dysfunction (26.3 vs. 19.4%, P = 0.035). In the patients with early RA, patients with myopenia showed a higher prevalence of physical dysfunction than those without myopenia (41.3 vs. 15.5%, P < 0.001), among which walking and common daily activities were the most involved subdimensions. Multivariate logistic regression analysis showed that DAS28-CRP was positively associated with myopenia [adjusted odds ratio (AOR) 1.558, 95% CI (1.138-2.132)], and myopenia [AOR 2.983, 95% CI (1.192-7.465)] was independently associated with physical dysfunction in the patients with early RA. Conclusion: Our data indicate the importance of early detection of muscle involvement in the early stage of RA and imply the significance of early aggressive control of disease activity for the prevention of myopenia and physical dysfunction in patients with early RA. Our study provides a new perspective on RA management.

Prevalence and influence of hypouricemia on cardiovascular diseases in patients with rheumatoid arthritis.

BACKGROUND: Serum uric acid (SUA) acts as an antioxidant and abnormally low SUA may raise the risk of developing atherosclerotic disorders. There is a U-shaped association between SUA with cardiovascular diseases (CVDs) in general population. However, the prevalence of hypouricemia and its influence on CVDs in rheumatoid arthritis (RA) remains unclear. METHODS: This cross-sectional study collected clinical data from a Chinese RA cohort. Hypouricemia was defined as SUA ≤ 3.0 mg/dL, and hyperuricemia was defined as SUA ≥ 7.0 mg/dL. CVDs were defined as a history of angina pectoris, myocardial infarction, heart failure, stroke and peripheral arterial disease. Restricted cubic spline regression and logistic regression analysis were conducted to evaluate the associations between SUA levels and CVDs. RESULTS: Among 1130 RA patients recruited, the mean age was 53.2 years and 79.0% were female. The prevalence of hypouricemia and hyperuricemia were 10.6% and 12.0%, respectively. RA patients with hyperuricemia had a higher rate of CVDs than normouricemic patients (27.9% vs. 7.1%, P < 0.05). Surprisingly, RA patients with hypouricemia also had a higher rate of CVDs (20.7% vs. 7.1%, P < 0.05) even without higher traditional cardiovascular risk factors. A U-shaped association between SUA levels and total CVDs was found (Pnon-linear < 0.001). Multivariate logistic regression analysis revealed that compared with normouricemia, both hypouricemia [adjusted OR (AOR) = 4.707, 95% CI 2.570-8.620] and hyperuricemia (AOR = 3.707, 95% CI 2.174-6.321) were associated with higher risk of CVDs. CONCLUSIONS: Hypouricemia may be a potential risk factor of CVDs in RA patients.

Myokine myostatin is a novel predictor of one-year radiographic progression in patients with rheumatoid arthritis: A prospective cohort study.

Background: Associations between rheumatoid arthritis (RA) and reduced skeletal muscle have been studied, and we firstly reported myopenia independently predict one-year radiographic progression in RA. Myokine myostatin can negatively regulate skeletal muscle mass and promote osteoclast differentiation. However, there is no report about their relationships in RA patients. We firstly explored the relationship of serum myostatin and disease characteristics, as well as aggravated joint destruction during one-year follow-up. Methods: Consecutive RA patients were recruited from a real-world prospective cohort and completed at least one-year follow-up. Baseline serum level of myostatin was measured by enzyme-linked immunosorbent assay. Clinical data in RA patients as well as muscle index in both RA patients and healthy controls were collected. One-year radiographic progression as primary outcome was defined by a change in the total Sharp/van der Heijde modified score ≥0.5 units. Results: Totally 344 RA patients (age 47.9 ± 12.5 years, 84.0% female) and 118 healthy control subjects (age 42.8 ± 11.3 years, 74.6% female) were recruited. Compared with healthy controls, RA patients showed a higher level of serum myostatin at baseline (3.241 ± 1.679 ng/ml vs. 1.717 ± 0.872 ng/ml, P<0.001), although lower appendicular skeletal muscle mass index (ASMI, 6.0 ± 0.9 kg/m2 vs. 6.5 ± 1.0 kg/m2, P<0.001). In RA patients, those with high myostatin level showed a higher rate of radiographic progression than low myostatin group (45.3% vs. 18.6%, P<0.001). Furtherly, RA patients were stratified into four subgroups according to serum myostatin and myopenia. Compared with other three subgroups, RA patients with high myostatin overlapping myopenia had the highest rate of radiographic progression (67.2% vs. 10.3%-31.4%, P<0.001), as well as the lowest proportion of remission and the highest rate of physical dysfunction during one-year follow-up. After adjustment for confounding factors, high serum myostatin (AOR=3.451, 95%CI: 2.016-5.905) and myopenia (AOR=2.387, 95%CI: 1.416-4.022) at baseline were risk factors for one-year radiographic progression, especially for those with high myostatin overlapping myopenia (AOR=10.425, 95%CI: 3.959-27.450) as the highest-risk individuals among four subgroups. Significant synergistic interaction effect was observed between high myostatin and myopenia on one-year radiographic progression (AP=66.3%, 95%CI: 43.2%-89.3%). Conclusion: Myostatin is a novel predictor of aggravated joint destruction in RA patients which has synergistic interaction with myopenia for predicting value.

Development and validation of equations for conversion from DAS28ESR and DAS28CRP to the SDAI in patients with rheumatoid arthritis.

INTRODUCTION: Disease Activity Score-28 (DAS28) with erythrocyte sedimentation rate (DAS28ESR), DAS28 with C-reactive protein (DAS28CRP), and simplified disease activity index (SDAI) are widely used to assess disease activity as low, moderate, or high or in remission in patients with rheumatoid arthritis (RA). However, these indicators can generate inconsistent results, influencing treatment decisions and limiting comparisons across studies. We aimed to establish equations for conversion from DAS28ESR and DAS28CRP to SDAI. METHODS: We conducted a retrospective study, including 933 outpatients who were simultaneously assessed using DAS28ESR, DAS28CRP, and SDAI. The patients were divided into a training set (70%) and a validation set (30%). We developed equations to convert DAS28ESR and DAS28CRP values into SDAI values by bisquare-weighted robust regression to obtain SDAI-DAS28ESR and SDAI-DAS28CRP. In addition to using kappa values to assess consistency, differences in disease activity classification between SDAI-DAS28ESR and SDAI-DAS28CRP were examined by the Stuart-Maxwell test and the Bowker test. RESULTS: Two quadratic equations were developed as follows: SDAI-DAS28ESR = 1.168 × (DAS28ESR)^2 - 2.432 × (DAS28ESR) + 2.649 and SDAI-DAS28CRP = 1.2 × (DAS28CRP)^2 - 0.3522 × (DAS28CRP) - 0.6014. After applying the equations, the Stuart-Maxwell test and the Bowker test were no longer significant between SDAI-DAS28ESR and SDAI or between SDAI-DAS28CRP and SDAI. The kappa values increased from 0.57 to 0.73 between SDAI-DAS28ESR and SDAI and 0.76 to 0.86 between SDAI-DAS28CRP and SDAI. CONCLUSION: SDAI-DAS28ESR and SDAI-DAS28CRP are interchangeable with the SDAI on the group level, which will facilitate comparisons among studies. In addition, the equations improved consistency between indicators. Key Points • There is disagreement in assessing disease activity in patients with rheumatoid arthritis between Disease Activity Score-28 (DAS28) with erythrocyte sedimentation rate (DAS28ESR), DAS28 with C-reactive protein (DAS28CRP), and simplified disease activity index (SDAI). • We developed and validated two quadratic equations to convert DAS28ESR and DAS28CRP into SDAI. We found there was no longer significant difference in disease activity between indicators after applying the equations. • This work may allow comparisons across studies which use different indicators.

Association Between Metabolic Dysfunction-Associated Fatty Liver Disease and Cardiovascular Risk in Patients With Rheumatoid Arthritis: A Cross-Sectional Study of Chinese Cohort.

Background: The nomenclature from non-alcoholic fatty liver disease (NAFLD) to metabolic dysfunction-associated fatty liver disease (MAFLD) is considered to identify more cardiovascular disease (CVD) risks in the general population. Patients with rheumatoid arthritis (RA) carry an excess risk for CVD. However, the prevalence of MAFLD and its relationship with CVD risks in RA have not been reported. Methods: This cross-sectional study retrospectively analyzed clinical data from a Chinese RA cohort. MAFLD was diagnosed according to the criteria proposed by an international expert panel from 22 countries in 2020. CVD risk in patients with RA was estimated by the Prediction for Atherosclerotic Cardiovascular Disease Risk in China with a 1.5 multiplication factor. Results: Among 513 included patients with RA, 78.4% were women and the mean ± SD age was 51.8 ± 12.6 years. The prevalence of MAFLD was 21.4%. There were 10.9% patients with RA concomitated with CVD events and 32.4% with a high-estimated 10-year CVD risk. Besides a higher liver fibrosis score and a higher ratio of advanced fibrosis, RA patients with MAFLD had a higher rate of CVD events (17.3 vs. 9.2%) and a higher proportion of high estimated 10-year CVD risk (55.5 vs. 26.1%) than those without. Multivariate logistic regression analysis showed that MAFLD was associated with an increase in CVD events [adjusted odds ratio (AOR) = 2.190, 95% CI 1.135-4.227] and high estimated 10-year CVD risk (AOR = 2.483, 95% CI 1.412-4.365, all p < 0.05). Conclusion: Metabolic dysfunction-associated fatty liver disease was associated with increased CVD risk in patients with RA, which implies the importance of early detection and management of MAFLD in patients with RA.

A Matrix Prediction Model for the 6-Month Mortality Risk in Patients With Anti-Melanoma Differentiation-Associated Protein-5-Positive Dermatomyositis.

Objectives: The purpose of this study was to investigate the baseline independent risk factors for predicting 6-month mortality of patients with anti-melanoma differentiation-associated gene 5 (anti-MDA5)-positive dermatomyositis (DM) and develop a matrix prediction model formed by these risk factors. Methods: The hospitalized patients with DM who completed at least 6-month follow-up were recruited as a derivation cohort. The primary exposure was defined as positive anti-MDA5 at the baseline. The primary outcome was all-cause 6-month mortality after enrollment. A matrix prediction model was developed in the derivation cohort, and another published cohort was used for external validation. Results: In derivation cohort, 82 patients with DM were enrolled (mean age of onset 50 ± 11 years and 63% women), with 40 (49%) showing positive anti-MDA5. Gottron sign/papules (OR: 5.135, 95%CI: 1.489-17.708), arthritis (OR: 5.184, 95%CI: 1.455-18.467), interstitial lung disease (OR: 7.034, 95%CI: 1.157-42.785), and higher level of C4 (OR: 1.010, 95%CI: 1.002-1.017) were the independent associators with positive anti-MDA5 in patients with DM. Patients with anti-MDA5-positive DM had significant higher 6-month all-cause mortality than those with anti-MDA5-negative (30 vs. 0%). Among the patients with anti-MDA5-positive DM, compared to the survivors, non-survivors had significantly advanced age of onset (59 ± 6 years vs. 46 ± 9 years), higher rates of fever (75 vs. 18%), positive carcinoma embryonic antigen (CEA, 75 vs. 14%), higher level of ferritin (median 2,858 ug/L vs. 619 ug/L, all p < 0.05). A stepwise multivariate Cox regression showed that ferritin ≥1,250 µg/L (HR: 10.4, 95%CI: 1.8-59.9), fever (HR: 11.2, 95%CI: 2.5-49.9), and positive CEA (HR: 5.2, 95%CI: 1.0-25.7) were the independent risk factors of 6-month mortality. A matrix prediction model was built to stratify patients with anti-MDA5-positive DM into different subgroups with various probabilities of 6-month mortality risk. In an external validation cohort, the observed 6-month all-cause mortality was 78% in high-risk group, 43% in moderate-risk group, and 25% in low-risk group, which shows good accuracy of the model. Conclusion: Baseline characteristics such as fever, ferritin ≥1,250 µg/L, and positive CEA are the independent risk factors for 6-month all-cause mortality in patients with anti-MDA5-positive DM. A novel matrix prediction model composed of these three clinical indicators is first proposed to provide a chance for the exploration of individual treatment strategies in anti-MDA5-positive DM subgroups with various probabilities of mortality risk.

Addition of Fibroblast-Stromal Cell Markers to Immune Synovium Pathotypes Better Predicts Radiographic Progression at 1 Year in Active Rheumatoid Arthritis.

Objectives: This study aims to investigate if addition of fibroblast-stromal cell markers to a classification of synovial pathotypes improves their predictive value on clinical outcomes in rheumatoid arthritis (RA). Methods: Active RA patients with a knee needle synovial biopsy at baseline and finished 1-year follow-up were recruited from a real-world prospective cohort. Positive staining for CD20, CD38, CD3, CD68, CD31, and CD90 were scored semiquantitatively (0-4). The primary outcome was radiographic progression defined as a minimum increase of 0.5 units of the modified total Sharp score from baseline to 1 year. Results: Among 150 recruited RA patients, 123 (82%) had qualified synovial tissue. Higher scores of CD20+ B cells, sublining CD68+ macrophages, CD31+ endothelial cells, and CD90+ fibroblasts were associated with less decrease in disease activity and greater increase in radiographic progression. A new fibroblast-based classification of synovial pathotypes giving more priority to myeloid and stromal cells classified samples as myeloid-stromal (57.7%, 71/123), lymphoid (31.7%, 39/123), and paucicellular pathotypes (10.6%, 13/123). RA patients with myeloid-stromal pathotype showed the highest rate of radiographic progression (43.7% vs. 23.1% vs. 7.7%, p = 0.011), together with the lowest rate of Boolean remission at 3, 6, and 12 months. Baseline synovial myeloid-stromal pathotype independently predicted radiographic progression at 1 year (adjusted OR: 3.199, 95% confidence interval (95% CI): 1.278, 8.010). Similar results were obtained in a subgroup analysis of treatment-naive RA. Conclusions: This novel fibroblast-based myeloid-stromal pathotype could predict radiographic progression at 1 year in active RA patients which may contribute to the shift of therapeutic decision in RA.

Neglected extra-articular manifestations in rheumatoid arthritis patients with normal body mass index: reduced skeletal muscle overlapping overfat.

BACKGROUND: Chronic inflammation in rheumatoid arthritis (RA) can induce reduced muscle mass (myopenia) and ectopic fat deposition probably showing normal body mass index (BMI). We aimed to investigate their body composition (BC) characteristics and clinical significance. METHODS: BMI and BC were collected in consecutive RA patients and control subjects. Myopenia was defined by appendicular skeletal muscle mass index (ASMI) ⩽7.0 kg/m2 in men and ⩽5.7 kg/m2 in women. Overfat was defined by body fat percentage (BF%) as ⩾25% for men and ⩾35% for women. RESULTS: There were 620 RA patients (57.6% with normal BMI) and 2537 control subjects (62.5% with normal BMI) recruited. After 1:1 age and sex matching with control subjects, RA patients with normal BMI (n = 240) showed significantly higher prevalence of myopenia (43.3% versus 22.1%) and overfat (19.2% versus 7.1%) as well as myopenia overlapping overfat (17.1% versus 3.3%). In all RA patients with normal BMI (n = 357), there were 18.2% patients with myopenia overlapping overfat who had the worst radiographic scores and highest rates of previous glucocorticoid treatment and hypertension. Compared with those without, normal BMI RA patients with previous glucocorticoid treatment (24.4% versus 10.3%) or hypertension (27.8% versus 13.6%) had a higher rate of myopenia overlapping overfat. Previous glucocorticoid treatment [odds ratio (OR) = 2.844, 95% confidence interval (CI) 1.441-5.614] and hypertension (OR = 2.452, 95% CI 1.283-4.685) were potential associated factors of myopenia overlapping overfat in RA patients with normal BMI. CONCLUSION: Myopenia overlapping overfat is an important extra-articular manifestation which should not be ignored in RA patients with normal BMI, especially with glucocorticoid treatment and hypertension.

Reduced skeletal muscle independently predicts 1-year aggravated joint destruction in patients with rheumatoid arthritis.

BACKGROUND: Numerous cross-sectional studies have reported the associations between rheumatoid arthritis (RA) and reduced skeletal muscle. We firstly explored the dynamic change of skeletal muscle and its effect on RA clinical outcomes in a real-world prospective cohort. METHODS: Consecutive RA patients were treated according to the treat-to-target strategy and completed at least 1-year follow up. Clinical data and muscle index (assessed by bioelectric impedance analysis) were collected at baseline and visits at 3, 6, 9 and 12 months. Myopenia was defined by appendicular skeletal muscle mass index ⩽7.0 kg/m2 in men and ⩽5.7 kg/m2 in women. A 1-year radiographic progression as primary outcome was defined by a change in the total Sharp/van der Heijde modified score ⩾0.5 units. RESULTS: Among 348 recruited patients, 315 RA patients (mean age 47.9 years, 84.4% female) completed 1-year follow up. There were 143 (45.4%) RA patients showing myopenia at baseline. Compared with those without baseline myopenia, RA patients with baseline myopenia had higher rate of 1-year radiographic progression (43.4% versus 21.5%, all p < 0.05). Baseline myopenia was an independent risk factor for 1-year radiographic progression with adjusted odds ratio (AOR) of 2.5-fold, especially among RA patients in remission at baseline both defined by Disease Activity Score in 28 joints (DAS28) including C-reactive protein (DAS28-CRP) or erythrocyte sedimentation rate (DAS28-ESR) with AOR of 18.5~42.9-fold. Further analysis of six subtypes of dynamic skeletal muscle change showed that newly acquired myopenia at endpoint was associated with radiographic progression (AOR of 5.4-fold). CONCLUSIONS: Reduced skeletal muscle is an independent predicting factor for 1-year aggravated joint destruction, especially in remission RA. The importance of dynamic monitoring of skeletal muscle and muscle improvement therapy are worth exploration.

Activation of the Peroxisome Proliferator-Activated Receptor γ Coactivator 1ß/NFATc1 Pathway in Circulating Osteoclast Precursors Associated With Bone Destruction in Rheumatoid Arthritis.

OBJECTIVE: Activation of osteoclastogenesis at the bone site in rheumatoid arthritis (RA) is well established. The mechanisms by which circulating osteoclast precursors contribute are still unclear. Peroxisome proliferator-activated receptor γ coactivator 1ß (PGC-1ß) is implicated in transcriptional regulation of osteoclastogenesis in mouse models. This study was undertaken to investigate the contribution of PGC-1ß to circulating osteoclast precursors and its link to bone destruction in RA. METHODS: PGC-1ß expression in RA peripheral blood CD14+ monocytes was increased and showed correlation with joint destruction shown on radiographs. Cells from RA patients or healthy controls were transfected with a lentivirus vector for PGC-1ß gene silencing or overexpression and cultured with macrophage colony-stimulating factor and RANKL. Bone resorption activity, bone-degrading enzymes, and signaling molecules were measured in these mature osteoclasts. RESULTS: Increased nuclear accumulation of PGC-1ß was observed in RA peripheral blood CD14+ monocytes, and these cells had stronger osteoclastogenesis than in healthy controls. PGC-1ß protein expression was positively correlated with radiographic joint destruction (r = 0.396-0.413; all P < 0.05). PGC-1ß knockdown suppressed (51-82% reduction) the expression of cathepsin K, tartrate-resistant acid phosphatase (TRAP), and matrix metalloproteinase 9 (MMP-9), as well as osteoclast differentiation and bone resorption activity. Conversely, PGC-1ß overexpression increased these markers (by 1.5-1.8-fold) and osteoclastogenesis. VIVIT, an inhibitor of NFATc1 activation, inhibited the effect of overexpressed PGC-1ß by reducing cathepsin K, TRAP, and MMP-9 expression. Chromatin immunoprecipitation assay and dual-luciferase reporter gene assay showed PGC-1ß bound to NFATc1 promoter, leading to transcriptional activation. CONCLUSION: Activation of the PGC-1ß/NFATc1 pathway in circulating osteoclast precursors was associated with bone destruction in RA. This may represent a new treatment target.

Myopenia is associated with joint damage in rheumatoid arthritis: a cross-sectional study.

BACKGROUND: The link between body mass index (BMI) and disease characteristics in rheumatoid arthritis (RA) remains controversial. Body composition (BC) has been more frequently recommended to be used instead of BMI for more accurate assessment. Our study aimed to investigate the characteristics of BC in RA patients and their associations with disease characteristics. METHODS: Body composition was assessed in consecutive Chinese RA patients and control subjects by bioelectric impedance analysis. Overfat was defined by body fat percentage (BF%) as ≥25% for men and ≥35% for women. Myopenia was defined by appendicular skeletal muscle mass index (ASMI) ≤7.0 kg/m2 in men and ≤5.7 kg/m2 in women. BMI and clinical data including disease activity, function, and radiographic assessment were collected. Active disease was defined by disease activity score in 28 joints with four variables including C-reactive protein (DAS28-CRP) ≥2.6. Functional limitation was defined as Stanford health assessment questionnaire disability index (HAQ-DI) >1. Radiographic joint damage (RJD) was defined as the Sharp/van der Heijde modified sharp score (mTSS) >10. RESULTS: There were 457 RA patients (mean age 49.5 ± 13.1 years old with 82.7% women) and 1860 control subjects (mean age 34.3 ± 9.9 years old with 51.2% women) recruited. Comparisons of BMI and BC between RA patients and control subjects in age and gender stratification showed that lower BMI with 17.7% underweight and lower ASMI with 45.1% myopenia are the main characteristics in RA patients. Compared with those without myopenia, RA patients with myopenia had significantly higher DAS28-CRP (median 3.5 vs. 3.0), higher HAQ-DI (median 0.38 vs. 0.13) with higher rate of functional limitation (24.8% vs. 7.6%), and higher mTSS (median 22.3 vs. 9.0) with more RJD (71.8% vs. 45.8%) (all P < 0.001). Multivariate logistic regression analysis showed myopenia were positively associated with functional limitation (OR = 2.546, 95% CI: 1.043-6.217) and RJD (OR = 2.660, 95% CI: 1.443-4.904). All RA patients were divided into four BC subgroups according to overfat and myopenia. Those with both overfat and myopenia had the worst disease characteristics. After adjustment for confounding factors, significant additive interactions were observed between overfat and myopenia in active disease (AP = 0.528, 95% CI: 0.086-0.971), functional limitation (AP = 0.647, 95% CI: 0.356-0.937), and RJD (AP = 0.514, 95% CI: 0.139-0.890). CONCLUSIONS: Myopenia is very common in RA patients that is associated with functional limitation and joint damage in RA. Further research on the underlying mechanism and the effect of skeletal muscle mass improvement in RA management are worth exploring in the future.

Deleterious role of hepatitis B virus infection in therapeutic response among patients with rheumatoid arthritis in a clinical practice setting: a case-control study.

BACKGROUND: Previous studies have revealed that hepatitis B virus (HBV) infection may be associated with rheumatoid arthritis (RA), while there are no further clinical studies regarding the role of HBV infection in RA progression during disease-modifying anti-rheumatic drug (DMARD) therapy. Here, we aimed to explore the influence of HBV infection on radiographic and clinical outcomes among patients with RA in a clinical practice setting. METHODS: Thirty-two consecutive patients with RA (Disease Activity Score 28-joint assessment based on C-reactive protein (DAS28-CRP) ≥2.6) with chronic HBV infection (CHB) were retrospectively recruited as the CHB group and 128 age-matched, sex-matched, and disease activity-matched contemporary patients with RA without CHB were included in the non-CHB group. Clinical data were collected at baseline and visits at month 1, 3, 6, and 12. The therapeutic target was defined as DAS28-CRP <2.6 in all patients or <3.2 in patients with long disease duration (>24 months). The primary outcome was the percentage of patients with one-year radiographic progression (a change in modified total Sharp score ≥0.5). RESULTS: Compared with the non-CHB group, a significantly higher percentage of patients with one-year radiographic progression was observed in the CHB group (53% vs. 17%, p < 0.001), with smaller proportions of patients achieving therapeutic target at month 6 and month 12 (53% vs. 82% and 53% vs. 75%, both p < 0.05), remission at month 6 (DAS28-CRP <2.6, 50% vs. 72%, p = 0.039), and American College of Rheumatology (ACR)20/50 responses and good or moderate European League Against Rheumatism (EULAR) responses mainly at month 6 and 12 (all p < 0.05). Multivariate logistic regression analysis revealed that CHB status was significantly associated with one-year radiographic progression and failure to achieve therapeutic target within 6 months. HBV reactivation occurred in 34% of patients with CHB during one-year follow up, with two patients suffering hepatitis flare. CONCLUSIONS: HBV infection may play a deleterious role in radiographic and clinical outcomes in patients with RA, and HBV reactivation should be paid close attention during immunosuppressive therapy.

Joint damage is amplified in rheumatoid arthritis patients with positive thyroid autoantibodies.

BACKGROUND: Autoimmune thyroid disease (AITD), which is characterized by an increased presence of thyroid autoantibodies (TAbs), such as antibodies against thyroid peroxidase (TPOAbs) and antibodies against thyroglobulin (TgAbs), has been reported to be associated with rheumatoid arthritis (RA) because AITD and RA both involve autoimmunity. However, few data are available on the incidence of TAbs in Chinese RA patients, and studies on the association between TAbs and joint damage as well as synovitis in RA patients remain sparse. Here, we aimed to evaluate the incidence of TAbs in a consecutive Chinese RA cohort and to investigate whether the elevated presence of TAbs is associated with joint damage and synovitis in RA patients. METHODS: A total of 125 hospitalized RA patients were consecutively recruited. Clinical data and available synovial tissues were collected at baseline, and TAbs and thyroid function were detected by chemiluminescent immunoassay. Patients who tested positive for TPOAbs or TgAbs were classified as the TAbs-positive group, and patients who tested positive for neither TPOAbs nor TgAbs were recruited as the TAbs-negative group. Disease activity was assessed using DAS28-ESR (the disease activity score in 28 joints and including the erythrocyte sedimentation rate). X-ray assessment of the hand/wrist was performed according to the Sharp/van der Heijde-modified Sharp score (mTSS), and patients with an mTSS score >10 were defined as having radiographic joint damage (RJD). Serial tissue sections were stained immunohistochemically for CD3, CD15, CD20, CD34, CD38, and CD68, and synovitis were assessed according to Krenn's synovitis score. RESULTS: A total of 44 (35%) patients were positive for either TPOAbs or TgAbs. Importantly, there was a significantly greater percentage of patients with RJD in the TAbs-positive group versus the TAbs-negative group (68% vs. 42%, p = 0.005). Compared with the TAbs-negative group, significantly more CD38-positive plasma cells infiltrated the TAbs-positive synovium, and a higher percentage of patients with high-grade synovitis were observed in the TAbs-positive group (5/8, 63% vs. 5/14, 36%). Moreover, RF positivity and disease activity indicators, including TJC28, DAS28-ESR, and CDAI, were significantly higher in the TAbs-positive group (all p < 0.05). Adjusted logistic regression analysis revealed that positive TAbs (OR 2.999, 95% CI [1.301-6.913]; p = 0.010) and disease duration (OR 1.013, 95% CI [1.006-1.019]; p < 0.001) were independently associated with RJD, and an odds ratio of 2.845 (95% CI [1.062-7.622]) was found for RJD in women with positive TAbs (n = 37) compared with those without TAbs (n = 59) (p = 0.038). CONCLUSION: Our data showed that joint destruction was amplified in RA patients with an elevated presence of TAbs, which supports the importance and necessity of TAbs and thyroid function screening and monitoring in RA patient management in clinical practice.