Evaluation of disease activity indices in Korean patients with rheumatoid arthritis

The aim of this study is to examine the validity of the rheumatoid arthritis (RA), disease activity score (DAS), 28-C-reactive protein (CRP), the simplified disease activity index (SDAI), and the clinical disease activity index (CDAI) against the DAS28-erythrocyte sedimentation rate (ESR) and determine cut-off values for each tool in Korean patients with RA. A total of 223 RA patients were consecutively recruited from the Hanyang University Hospital for Rheumatic Diseases in Seoul, Korea. DAS28-CRP, SDAI, and CDAI were measured and compared with DAS28-ESR. The correlation coefficients of DAS28-ESR with DAS28-CRP, SDAI, and CDAI were 0.93, 0.85, and 0.84, demonstrating strong linear relationships. The cut-off values of DAS28-CRP classifying RA patients into four categories of disease activity were defined as 2.19, 2.60, and 4.07. SDAI cut-off values were defined as 3.75, 7.50, and 16.88. CDAI cut-off values were defined as 3.62, 7.38, and 16.50. DAS28-CRP, SDAI, and CDAI are valid and sensitive assessment indices of disease activity that are comparable to DAS28-ESR. The cut-off values of each tool derived in this study might be useful for routine monitoring and therapeutic decision-making in Korean RA patients.     

Serum adenosine deaminase may predict disease activity in rheumatoid arthritis

To determine the relationship between serum adenosine deaminase (ADA) and disease activity, and to develop a new disease activity index based on serum ADA in rheumatoid arthritis (RA). Seventy RA patients were included. Disease activity based on Disease Activity Score 28-ESR (DAS28-ESR) and Disease Activity Score 28-CRP (DAS28-CRP) and serum ADA were measured. There were correlations when serum ADA compared with DAS28-ESR and DAS28-CRP. (R ²?=?0.014, 0.175, respectively, P values?<?0.00). New disease activity index was developed by replacing ADA with ESR and CRP in DAS28-ESR and DAS28-CRP. There were strong correlations when new model compared with DAS28-ESR and DAS28-CRP. (R ²?=?0.94 and 0.95, respectively, P values?<?0.00) The best new model values corresponding to DAS28-ESR values of 2.6, 3.2, and 5.1 were 2.79, 3.4, and 4.82, respectively; and new model values corresponding to DAS28-CRP values of 2.3, 2.7, and 4.1 were 2.1, 2.9, and 4, respectively. There were agreements when the new model compared with DAS28-ESR and DAS28-CRP for determination of patients in different disease activity categories. (Kappa?=?0.81 and 0.71, respectively, P values?<?0.00). The new disease activity index that applies serum ADA may help in predicting disease activity in RA.     

The efficacy of abatacept in Japanese patients with rheumatoid arthritis: 104 weeks radiographic and clinical results in clinical practice

Objective: We aimed to assess the efficacy of abatacept in Japanese patients with rheumatoid arthritis (RA) in clinical practice.

Methods: We examined 92 patients who received abatacept for 104 weeks. Analysis of radiographic efficacy was conducted using van der Heijde-modified total Sharp score (mTSS). Disease activity score was assessed using disease activity score in 28 joints (DAS28) and simplified disease activity index (SDAI) by last observation carried forward.

Results: The change in mTSS was 0.61 at 52 weeks and 0.27 at 52–104 weeks. Structural remission occurred in 64.9% at 52 weeks and 76.6% at 104 weeks. The significant risk factors for joint damage progression at 52 weeks were prednisolone use, baseline C-reactive protein level (CRP), and erythrocyte sedimentation rate (ESR), as well as average DAS28-CRP and DAS28-ESR scores, SDAI, CRP, ESR, and matrix metalloproteinase-3 (MMP-3) levels. The clinical remission rates were 47.8% by DAS28-CRP, 39.1% by DAS28-ESR, and 30.4% by SDAI at 52 weeks, were 59.8% by DAS28-CRP, 48.9% by DAS28-ESR, and 43.5% by SDAI at 104 weeks.

Conclusion: This study suggested efficacy of abatacept treatment in Japanese patient with RA for 104 weeks in daily clinical practice. Abatacept lead to suppress joint destruction for 104 weeks.     

Comparison of composite disease activity indices for rheumatoid arthritis

To evaluate the composite disease activity indices for rheumatoid arthritis (RA), we compared disease activities and the changes therein calculated using the Disease Activity Score based on 28 joint counts using erythrocyte sedimentation rate (DAS28-ESR), DAS28-CRP (C-reactive protein), Simplified Disease Activity Index (SDAI), and Clinical Disease Activity Index (CDAI) in a cohort of 1,412 patients with RA. The median (1st; 3rd quartile) scores were 4.20 (3.31; 5.14) for DAS28-ESR, 3.44 (2.59; 4.36) for DAS28-CRP, 13.6 (7.49; 21.1) for SDAI, and 12.0 (6.9; 18.9) for CDAI. Absolute scores and their changes were significantly correlated (p < 0.0001) in all combinations among these four disease activity indices; however, their correlations were lower in males than in females. Correlations between disease activity indices and the clinical and acute phase reactant variables were different according to disease activity index, sex and age. A comparison of the number of patients in each disease activity category according to the disease activity indices using kappa-statistics revealed an almost perfect agreement between SDAI and CDAI (κ = 0.871), a moderate agreement between DAS28-ESR and SDAI (κ = 0.415) or CDAI (κ = 0.427), but only fair agreement between DAS28-ESR and DAS28-CRP (κ = 0.329). For the selection of a disease activity index for an evaluation of RA patients, both the convenience and the characteristics of the respective disease activity index should be considered.     

Revising DAS28 scores for remission in rheumatoid arthritis

Current initiatives to treat rheumatoid arthritis (RA) to target remission have resulted in the widespread use of composite outcome measures to quantify disease activity. Simplified Disease Activity Index (SDAI) ≤3.3 is the gold standard of remission. Previous work has suggested that the remission threshold of DAS28-ESR or DAS28-CRP ≤2.6 is known to be not strict enough and should be revised. There is no previous study that looks at the equivalent DAS28-CRP value that best reflects SDAI remission in a real-life cohort. Consecutive cases fulfilling ACR/EULAR classification criteria for RA from one centre were included if they had an optimum number of visits with recording of all raw data to calculate DAS28-ESR, DAS28-CRP and SDAI. Data from seven visits each of 76 patients, providing 532 data points was examined. Spearman’s correlation between DAS28-ESR, DAS28-CRP and SDAI was 0.91–0.97 (p?<?0.001). A Bland-Altman plot demonstrated a mean difference of 0.37 units between DAS28-ESR and DAS28-CRP (p?<?0.001). ROC and kappa analysis provided values of 2.58 and 2.55 for DAS28-ESR4V and 2.09 and 2.05 for DAS28-CRP4V for SDAI value of 3.3, respectively. The two versions of DAS28 using ESR and CRP and SDAI correlate but are not equivalent or interchangeable for an individual patient. The DAS28-CRP overestimates remission and should be revised downwards to a proposed value of 2.1.     

Comparison of Disease Activity Score (DAS)28- erythrocyte sedimentation rate and DAS28- C-reactive protein threshold values

OBJECTIVE: To estimate the disease activity score (DAS)28-C-reactive protein (CRP) threshold values that correspond to DAS28-erythrocyte sedimentation rate (ESR) values for remission, low disease activity and high disease activity in patients with rheumatoid arthritis. METHODS: DAS28 data were analysed using a large observational study (Institute of Rheumatology Rheumatoid Arthritis) database of 6729 patients with rheumatoid arthritis. Firstly, the relationship between the DAS28-ESR and the DAS28-CRP values was analysed. Secondly, the best DAS28-CRP trade-off values for each threshold were calculated using receiver operating characteristic (ROC) curves. RESULTS: The correlation coefficient of ESR versus CRP was 0.686, whereas that of DAS28-ESR versus DAS28-CRP was 0.946, showing the strong linear relationship between DAS28-ESR and DAS28-CRP values. DAS28-CRP threshold values corresponding to remission, low disease activity and high disease activity were 2.3, 2.7 and 4.1, respectively. The sensitivity and specificity from the ROC curves were gradually reduced as DAS28 values became lower. CONCLUSIONS: This study showed that DAS28-CRP and DAS28-ESR were well correlated, but the threshold values should be reconsidered. As the results were derived from only Japanese patients, it is essential to compare DAS28-CRP threshold values in people of other ethnic groups.     

Gastroesophageal reflux disease in patients with rheumatoid arthritis

Abstract

Objective. Patients with rheumatoid arthritis (RA) are frequently complicated with gastric mucosal injury; however, there are few reports investigating gastroesophageal reflux disease (GERD) among patients with RA. We investigated the frequency of GERD and the correlation between GERD and the clinical characteristics of RA including patient's global assessment (PGA).

Methods. Patients with RA were investigated for GERD using self-administered frequency scale for the symptoms of GERD (FSSG). The correlation between GERD and the clinical characteristics of RA was analyzed statistically.

Results. Two hundred and eleven patients in Japan were investigated. The prevalence of GERD among patients with RA (24.6%) was significantly higher than that in the Japanese population (11.5%) (p < 0.001). FSSG was positively correlated with modified health assessment questionnaire (mHAQ), PGA, evaluator's global assessment (EGA) (p < 0.001), disease activity score (DAS)28-erythrocyte sedimentation rate (ESR) (p < 0.05), DAS28-C-reactive protein (CRP), simplified disease activity index (SDAI) and clinical disease activity index (CDAI) (p < 0.001). The patients with GERD showed significantly higher scores in mHAQ, PGA, EGA, tenderness joint count, DAS28-ESR, DAS28-CRP, SDAI and CDAI (p < 0.001). Furthermore, the patients with GERD showed lower remission rates based on DAS28-ESR (p < 0.05), DAS28-CRP, SDAI and CDAI (p < 0.001).

Conclusion. GERD complicated with RA increases PGA and the indices of disease activity. GERD symptoms analyzed using FSSG may be desirable to avoid the overestimation as part of the total management of patients with RA.     

Serum-soluble folate receptor β as a biomarker for the activity of rheumatoid arthritis synovitis and the response to anti-TNF agents

This study aims to develop a sandwich ELISA system for the measurement of soluble folate receptor β (sFRβ) and evaluate whether base line levels of serum sFRβ are a biomarker for the activity of RA synovitis and the response to anti-TNF agents. Serum sFRβ from normal controls (41 samples), patients with OA (29 samples), and patients with RA (27 samples) and synovial fluid sFRβ from patients with RA (17 samples) were measured by sandwich ELISA, using anti-FRαβ and anti-FRβ antibodies as capture and detection antibodies, respectively. Baseline levels of serum sFRβ before therapy were evaluated in relation with DAS28-CRP or CRP and response to anti-TNF agents at 3-month follow-up. sFRβ levels in RA synovial fluids were higher than those in RA sera, and sFRβ levels in RA sera were higher than those in osteoarthritis and normal control sera. A significant relationship was observed between serum sFRβ levels and the DAS28-CRP scores or CRP values. The area under curve (AUC) values for receiver-operating characteristic curves defined using the serum sFRβ levels of RA patients before therapy had a higher predictive capacity than DAS28-CRP and CRP for the effective response of anti-TNF agents. The high serum sFRβ levels with a cutoff value of 8 ng/mL were 100% specificity for the effective response of anti-TNF agents. The findings support that the serum sFRβ levels in patients with RA act as a disease activation biomarker and that high serum sFRβ levels act as a predictive biomarker for the response to anti-TNF agents.     

Comparison between different disease activity scores in rheumatoid arthritis: an Egyptian multicenter study

The aim of our work was to assess the performance of different Disease Activity Score (DAS) other than DAS-ESR in daily clinical practice in our Egyptian outpatient clinics and also to evaluate the accuracy of European League Against Rheumatism Classification (EULAR) proposed cutoffs for these scores to stratify Egyptian patients into different categories of disease activity. This study is a cross-sectional Egyptian multicenter study. It included 130 rheumatoid arthritis (RA) patients who visited our Rheumatology and Rehabilitation outpatient and inpatient clinics; 80 patients from Cairo University Hospitals and 50 patients from Zagazig University Hospitals. The patients fulfilled the 2010 American College of Rheumatology (ACR)/European League Against Rheumatism Classification criteria for rheumatoid arthritis. Disease Activity Score 28-ESR (DAS28-ESR), DAS28-CRP, Simplified Disease Activity Index (SDAI), and Clinical Disease Activity Index (CDAI) were calculated. A significant positive correlation was found between all three scores and morning stiffness, ESR, Modified Health Assessment Questionnaire (MHAQ), and DAS-ESR. Also, there was a significant negative correlation between DAS-CRP and hemoglobin and a significant positive correlation with CRP. Also, there was a highly significant moderate agreement between DAS-ESR and DAS-CRP using Fleischmann et al. thresholds and also between DAS-ESR and SDAI. While a highly significant fair agreement was found between DAS-ESR and DAS-CRP using DAS-ESR thresholds and between DAS-ESR and CDAI. We conclude that DAS-CRP, SDAI, and CDAI are very useful in representing disease activity in RA patients in our outpatient clinics being well correlated with many markers of disease activity. We recommend huge multicenter studies in Egypt and in different populations to define new cutoff values to optimize their use in clinical setting.     

Disease Activity Score 28 (DAS28) using C-reactive protein underestimates disease activity and overestimates EULAR response criteria compared with DAS28 using erythrocyte sedimentation rate in a large observational cohort of rheumatoid arthritis patients in Japan

OBJECTIVES: To compare disease activity and the improvement of disease activity evaluated between by Disease Activity Score 28 using erythrocyte sedimentation rate (DAS28-ESR) and by DAS28 using C-reactive protein (DAS28-CRP) in Japanese patients with rheumatoid arthritis (RA). METHODS: Data from 3073 RA patients registered in the large cohort database (NinJa: National Database of Rheumatic Diseases by iR-net in Japan) of 2003 was used to calculate DAS28-ESR and DAS28-CRP and disease activities were evaluated. Improvements in disease activities were also evaluated according to the European League Against Rheumatism (EULAR) response criteria in 1482 RA patients whose DAS28-ESR and DAS28-CRP could be calculated from data for both 2002 and 2003. RESULTS: The mean value of DAS28-CRP (3.59, SD 1.25) was significantly smaller than that of mean DAS28-ESR (4.31, SD 1.32) (p < 0.0001). The number of patients who satisfied the criteria of remission was 297 (9.7%) in DAS28-ESR versus 705 (22.9%) in DAS28-CRP and the number of patients with high disease activity was 842 (27.4%) versus 357 (11.6%) for DAS28-ESR and DAS28-CRP, respectively; there was a significant difference between the two (p < 0.0001). Change of respective DAS28 was significantly correlated (DeltaDAS28-ESR -0.05, SD 1.14 versus DeltaDAS28-CRP -0.10, SD 1.10) (p < 0.0001); however, the number of "good response" patients was significantly different (p < 0.03) between DAS28-ESR (97 patients, 6.5%) and DAS28-CRP (136 patients, 9.2%). CONCLUSIONS: DAS28-CRP significantly underestimated disease activity and overestimated the improvement in disease activity compared with DAS28-ESR. DAS28-CRP should be evaluated using different criteria from that for DAS28-ESR.     

Patient-centered rheumatoid arthritis disease activity assessment by a modified RADAI

OBJECTIVE: To evaluate the psychometric properties and validity of a modified version of the Rheumatoid Arthritis Disease Activity Index (RADAI) without joint counts in order to facilitate rapid and easy RA activity assessment in daily routine. METHODS: One hundred sixty-nine outpatients with RA completed the original RADAI and the modified RADAI-5. Simultaneously, the Disease Activity Score-28-erythrocyte sedimentation rate (DAS28-ESR) and C-reactive protein (DAS28-CRP) and the Simplified Disease Activity Index (SDAI) and Clinical DAI (CDAI) were applied. Cronbach's alpha, as a measure for internal consistency, and Spearman's rho, to evaluate the linear relationship of the different disease activity scales, were calculated. Rho was determined for the RADAI-5 and the core set measures to assess convergent validity. For agreement analysis, kappa statistics were calculated. An attempt was made to estimate the modified questionnaire's sensitivity to change. RESULTS: Means for the RADAI and the RADAI-5 were 2.8 (range 0.0-9.12) and 3.07 (0-10), respectively. Other means were as follows: DAS28-ESR 3.51 (0.28-6.67), DAS28-CRP 3.19 (1.12-5.83), CDAI 11.53 (0.0-44.6), and SDAI 12.36 (0.1-44.9). Cronbach's alpha was highest for the RADAI-5 (0.917) and lowest for the DAS28-CRP (0.510). The RADAI-5 was highly significantly correlated (all p < 0.0001) to all other instruments. However, kappa was < 0.65 for the relation of the RADAI-5 and all other scores except the RADAI. Changes of the RADAI-5, DAS28-ESR, and CDAI were significantly correlated (p < 0.001). CONCLUSION: The RADAI-5, refraining from joint counts, was shown to be capable of measuring RA activity. Reliability and convergent validity could be proven.     

The value of changes in CRP and ESR for predicting treatment response in rheumatoid arthritis

Aim: During treatment of rheumatoid arthritis (RA) the serum C‐reactive protein (CRP) and erythrocyte sedimentation rate (ESR) decrease concurrent with clinical improvement. The aim of this paper is to investigate whether changes of these parameters could predict treatment response. Methods: Patients with active RA, requiring disease‐modyfying antirheumatic drugs were entered into the study. Serum CRP and ESR were assessed at baseline and 24 weeks after the treatment. Response to treatment was assessed by the RA Disease activity Score 28 (DAS28) and DAS28‐CRP response criteria. In statistical analysis the agreement between changes of CRP and ESR at the first stage of the treatment and DAS28/DAS28‐CRP were determined as ‘good’, ‘moderate’ and ‘none’ responses. The relationship between changes in CRP and DAS28‐CRP, ESR and DAS28 were also determined and compared. Results: Sixty‐six patients with active RA entered the study. The mean age was 50 ± 18 years and the mean disease duration was 4.9 ± 5.8 years. After an average period of 24 weeks, 51 patients met the DAS28 and 49 patients met the DAS28‐CRP response criteria as good or moderate responders. Over the treatment period a reduction of serum CRP predicted 90% of DAS28‐CRP responders and reduction of ESR predicted 97% of DAS28 responders, whereas a lack of CRP or ESR reductions predicted 54% and 45% non‐responders, respectively. Overall, the accuracy of changes in CRP and ESR in predicting treatment response according to DAS28‐CRP and DAS28 response criteria were 77% and 73%, respectively. CRP/DAS28‐CRP was more sensitive but less specific than ESR/DAS28 in predicting treatment response. Conclusion: Changes of CRP or ESR at the first stage of treatment can predict treatment response. Hence, measurement of serum CRP and ESR furnishes a reliable quantitative means for early anticipation of treatment response.     

Visualization of DAS28, SDAI,and CDAI: the magic carpets of rheumatoid arthritis

There has been continuous debate regarding the applicability of various composite measures for the assessment of disease activity in rheumatoid arthritis (RA). In order to further dissect this issue, we numerically and graphically modeled 28-joint disease activity scale (DAS28), simplified disease activity index (SDAI), and clinical disease activity index (CDAI) by three-dimensional (3D) plotting. We wished to graphically visualize the relative contribution of various elements in the three activity indices to each other. We calculated DAS28 (3 variables), SDAI, and CDAI by the standard equations. We plotted 3D “carpets” showing all combinations of the corresponding variables yielding to DAS28?=?5.1, DAS28?=?3.2, DAS28?=?2.6, SDAI?=?26, SDAI?=?11, and SDAI?=?3.3. We also plotted the 3D carpet for CDAI. In patients with high or moderate disease activity, erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) was not a major confounding factor when calculating DAS28 and SDAI, respectively. In contrast, ESR and CRP highly overshadowed changes in joint counts and global assessments in patients with low disease activity (LDA) or those in remission. No reliable assessment of LDA can be performed in cases where ESR >54 mm/h or CRP >20 mg/dl. Similarly, remission cannot be determined if ESR >19 mm/h or CRP >5 mg/dl. As CDAI does not include acute phase reactants, CDAI may be a useful tool even in states of remission or LDA. Our results suggest that acute phase reactants are indeed major confounding factors and should be omitted when assessing RA disease activity at least in special cases.     

Disease activity score 28 may overestimate the remission induction of rheumatoid arthritis patients treated with tocilizumab: comparison with the remission by the clinical disease activity index

We evaluated the efficacy of tocilizumab (TCZ) in patients with rheumatoid arthritis (RA) by the clinical disease activity index (CDAI) and disease activity score (DAS) 28-erythrocyte sedimentation rate (ESR). Thirty-two RA patients received 8?mg/kg of TCZ intravenously every 4?weeks for 48?weeks. The therapeutic response was also evaluated in 30 RA patients treated with 3?mg/kg of infliximab (IFX) for 46?weeks. We compared the therapeutic course of TCZ with IFX in order to evaluate the efficacy of TCZ therapy. A strong positive correlation between CDAI and DAS28-ESR was observed at baseline, whereas their associations dropped significantly within the first 2?months. The association recovered to the baseline by IFX, but still remained low in TCZ. Although a decrement of DAS28-ESR was prominent in TCZ as compared with IFX, that of CDAI was significant in the early phase and even in the latter in patients treated by IFX. The present study revealed that DAS28-ESR may not be sufficient to estimate RA disease activity treated by TCZ, probably due to the significant effect toward inhibition of acute phase reactants by TCZ. CDAI is suggested to be an important alternate of composite measure in these cases.     

Interchangeability of 28-joint disease activity scores using the erythrocyte sedimentation rate or the C-reactive protein as inflammatory marker

This paper aims to examine the interchangeability of the disease activity score in 28 joints (DAS28)-erythrocyte sedimentation rate (ESR) and DAS28-CRP scores in a diverse sample of rheumatoid arthritis (RA) patients and to evaluate generalizability over gender, age, and disease duration. A sample of 682 patients was drawn from the DREAM registry. Agreement between the two DAS28 scores was analyzed using the intraclass correlation coefficient (ICC), Bland Altman plots, and a matrix of classification agreement over DAS28 disease activity categories. Despite a strong linear correlation between the DAS28 scores and a high ICC value of 0.931, a considerable lack of individual agreement could be observed, with Bland-Altman 95 % limits of agreement ranging between ?0.85 and +1.25 points. On average, DAS28-CRP scores were 0.20 points lower than DAS28-ESR scores, and data stratification on age and gender showed that this systematic bias was most severe in older women (0.39 points). The overall classification agreement across DAS28 categories was 76.69 %, with the agreement being lowest (35.37 %) in the low disease activity group. Patients were more easily classified as being in remission when using the DAS28-CRP measure. DAS28-ESR and DAS28-CRP scores are not interchangeable within individuals. The DAS28-CRP tends to yield lower values of disease activity than the DAS28-ESR, resulting in substantial classification differences.     

Identification of clinical parameters associated with serum oxidative stress in patients with rheumatoid arthritis

Abstract

Objectives. Reactive oxygen species (ROS) are considered to be involved in the pathobiology of rheumatoid arthritis (RA); however, their association with disease activity has not been elucidated. In this study, we measured reactive oxygen metabolites (ROM) in patients with RA using a new Free Radical Analytical System and determined clinical parameters associated with ROM.

Methods. One hundred and fifty-two patients with RA and 80 patients with diabetes mellitus (DM) were included in this observational study. To measure ROM, the d-ROM test was performed on blood samples drawn from all subjects. The correlation between ROM and biomarkers, disease activity, doses of methotrexate (MTX), and prednisolone (PSL) were investigated.

Results. There were significant, positive correlations between ROM and CRP, matrix metalloproteinase 3 (MMP3), Disease Activity Score 28–erythrocyte sedimentation rate (DAS28-ESR), Clinical Disease Activity Index (CDAI), and the Simplified Disease Activity Index (SDAI). Multiple regression analysis revealed that CRP and DAS28-ESR were correlated with ROM.

Conclusions. The serum level of ROM was associated with CRP and DAS28-ESR, suggesting that ROM, in conjunction with CRP and MMP3, may be able to be used as a new biological disease marker to evaluate the disease activity of RA.     

High rate of improvement in serum matrix metalloproteinase-3 levels at 4 weeks predicts remission at 52 weeks in RA patients treated with adalimumab

Objective: This study aimed to determine whether serum matrix metalloproteinase-3 (MMP-3) levels can predict remission in rheumatoid arthritis (RA) patients treated with adalimumab (ADA).

Methods: Subjects were 114 RA patients continuously treated with ADA for 52 weeks. Predictive factors at baseline and 4 weeks after initiation of ADA therapy for the achievement of remission (28-point count Disease Activity Score-CRP (DAS28-CRP)?Results: DAS28-CRP at 4 weeks (odds ratio (OR) 0.614, 95% confidence interval (CI) 0.382–0.988) and improvement in serum MMP-3 levels at 4 weeks (OR 1.057, 95% CI 1.002–1.032) were independent predictors of remission at 52 weeks. The best cut-off level of DAS28-CRP and improvement in serum MMP-3 levels at 4 weeks for predicting remission at 52 weeks was 3.73 (sensitivity: 90%, specificity: 50%, area under the receiver operating characteristic curve (AUC): 62%) and 39.93% (sensitivity: 47%, specificity: 83%, AUC: 64%), respectively.

Conclusion: Our findings suggest that a high rate of improvement in serum MMP-3 levels at 4 weeks after initiation of ADA therapy can predict remission at 52 weeks in RA patients.     

Changes in serum interleukin-6 levels as possible predictor of efficacy of tocilizumab treatment in rheumatoid arthritis

Objectives: We aimed to evaluate the association between the change in serum IL-6 during the clinical course of tocilizumab (TCZ) therapy and rheumatoid arthritis (RA) disease activity or occurrence of adverse events.

Methods: General laboratory data including serum IL-6 levels and physical findings were obtained every 4 weeks, and, in addition, at the time when any adverse events occurred.

Results: The proportion achieving Clinical Disease Activity Index (CDAI) remission at 52 weeks was significantly lower in 20 patients with serum IL-6?≥?30?pg/ml at 12 weeks than 24 patients with serum IL-6?Conclusion: Serum IL-6 levels from 12 to 24 weeks after TCZ initiation better reflect the efficacy of TCZ at 52 weeks.     

Serum anti-cyclic citrullinated peptide antibodies may predict disease activity in rheumatoid arthritis

To define the relationship between serum anti-cyclic citrullinated peptide antibodies (anti-CCP) and disease activity, and to construct a new disease activity index by using anti-CCP in rheumatoid arthritis (RA). One hundred and five RA patients were included. Disease activity based on DAS28-ESR and serum anti-CCP was measured. There was correlation between serum anti-CCP and DAS28-ESR. (R ²?=?0.71, P value?<?0.01). New disease activity index was developed by replacing anti-CCP with ESR in DAS28-ESR. There was correlation between new model and DAS28-ESR. (R ²?=?0.91, P value?<?0.01) The new composite index best cut-off values corresponding to DAS28-ESR values of 2.6, 3.2, and 5.1 were 3.21, 3.38, and 4.74, respectively. There was agreement between new model and DAS28-ESR for determination of patients in different disease activity categories. (Kappa?=?0.71, P value?<?0.01). The new disease activity index that applies serum anti-CCP may predict disease activity in RA.     

Fractures lead to worsening of disease activity in rheumatoid arthritis

Objectives: The cause of rheumatoid arthritis (RA) flares is multifactorial and not well understood. No reports of fractures influencing disease activity in patients with RA have been published. The purpose of this study was to determine whether fractures influence disease activity in patients with RA.

Methods: Hospital records of 470 patients with RA between 2011 and 2014 were analyzed. We first examined the incidence of flare using multiple regression analysis. Secondly, we examined the incidence of flare using DAS28-ESR, DAS28-CRP, and drug changes before bone fracture until bone union in the fracture cases.

Results: Multiple linear regression analysis showed that female sex (p?<?0.001), bottom DAS28-ESR (p?<?0.001), and fracture (p?=?0.041) were independent factor for DAS28-ESR at the last observation period, and sex (p?=?0.040), bottom DAS28-CRP (p?<?0.001), and fracture (p?=?0.019) were independent factor for DAS28-CRP at the last observation period. The average DAS28-ESR value was significantly increased from 3.19 (prefracture) to 3.58 (bone union). The average DAS28-CRP value was also significantly increased from 2.45 (prefracture) to 2.79 (bone union).

Conclusions: We have demonstrated that fractures influence disease activity in patients with RA. Larger numbers of fracture cases are required to confirm the present observations; however, the prevention of fracture is clearly required in patients with RA.