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ID PMID Title PublicationDate abstract
20483050 Evaluation of disease activity assessments in patients with rheumatoid arthritis and an in 2010 Mar OBJECTIVES: To assess the ability of efficacy measures that incorporate onset or sustainability to detect treatment effect or reflect patient satisfaction, using exploratory analyses of data from the ATTAIN (Abatacept Trial in Treatment of Anti-TNF INadequate Responders) trial. METHODS: 218 abatacept- and 99 placebo-treated patients were evaluated. Reporting methods included time to onset (first American College of Rheumatology [ACR] 50 response/Low Disease Activity State [LDAS; DAS28 < or =3.2]) and sustainability of ACR50/LDAS, both assessed according to discriminatory capacity (number of patients needed to study [NNS]) and patient satisfaction with treatment. RESULTS: Efficacy measures incorporating elements of sustainability or onset decreased discriminatory capacity, while sustainability, but not onset of action, was important in reflecting patient satisfaction. CONCLUSIONS: Optimal assessment methods depend on whether the outcome of interest is ability to detect treatment effects or to reflect patient satisfaction. Sustainability of response (and possibly, at a lower magnitude, fast onset of action) may be important when evaluating patient satisfaction with RA therapies in patients who have previously failed anti-TNF therapy.
20158887 Functional consequences of DECTIN-1 early stop codon polymorphism Y238X in rheumatoid arth 2010 INTRODUCTION: Dectin-1, a pattern recognition receptor expressed by the innate immune system, is known to be a major receptor inducing Th17-type adaptive immune responses that have been demonstrated to mediate autoimmunity. In this study, dectin-1 mRNA and protein expression, as well as the recently characterized DECTIN-1 Y238X early stop codon polymorphism, were studied in relation to rheumatoid arthritis (RA) susceptibility and severity. METHODS: Dectin-1 mRNA expression was measured in synovial tissue specimens of RA, osteoarthritis (OA), and nonrheumatic patients. Dectin-1 protein expression and localization were assessed in RA synovial tissue specimens. Macrophages from individuals with different DECTIN-1 genotypes were examined for differences in cytokine responses on dectin-1 stimulation. Furthermore, clinical parameters of inflammation and bone destruction of 262 RA patients were correlated with the presence of the DECTIN-1 Y238X polymorphism. RESULTS: Evaluation of dectin-1 mRNA expression in synovial tissue biopsies revealed an increased expression in RA specimens, compared with biopsies from OA and nonrheumatic patients. Accordingly, dectin-1 protein expression in RA synovial tissue biopsies was moderate to high, especially on macrophage-like cells. Cytokine production capacity of macrophages bearing the DECTIN-1 Y238X polymorphism was demonstrated to be impaired on dectin-1 stimulation. However, the presence of the DECTIN-1 Y238X polymorphism was not associated with RA susceptibility or disease severity. CONCLUSIONS: Although expression of dectin-1 was high in synovial tissue of RA patients, and reduced cytokine production was observed in macrophages of individuals bearing the DECTIN-1 Y238X polymorphism, loss of one functional allele of DECTIN-1 is not associated with either susceptibility to or severity of RA.
20601897 Infliximab reduces the frequency of interleukin 17-producing cells and the amounts of inte 2010 Oct BACKGROUND: To detect frequency changes in interleukin 17 (IL-17)(+) CD4(+) T cells and the amounts of IL-17 in supernatants between baseline and 30 weeks after Infliximab combined with methotrexate (MTX) or MTX-alone therapy. METHODS: Flow cytometry was used to analyze the frequency of IL-17(+) CD4(+) T cells in rheumatoid arthritis (RA) patients and control subjects at baseline and 30 weeks after therapy. Secretion of IL-17 by peripheral blood mononuclear cells was measured by enzyme-linked immunosorbent assay. RESULTS: The percentages of IL-17(+) CD4(+)T cells were increased in the peripheral blood mononuclear cells of patients with RA compared with healthy subjects. The percentages of IL-17(+) CD4(+)T cells were correlated with the number of swelling joints and C-reactive protein of RA patients. Likewise, concentrations of IL-17 in supernatants from patients with RA were significantly higher compared with those from control subjects. After infliximab combined with MTX or MTX-alone therapy, the number of swelling joints, erythrocyte sedimentation rate, C-reactive protein, rheumatoid factor, and Disease Activity Score 28 decreased significantly compared with baseline. Only in the infliximab + MTX group that the frequency of T(H)17 cells and concentration of IL-17 decreased. CONCLUSIONS: These data support the hypothesis that infliximab therapy can have an effect on T(H)17 cells and decrease disease activity.
19434315 Immunohistochemical study of skeletal muscle in rheumatoid myositis. 2009 INTRODUCTION: Rheumatoid myositis (RM) represents a poorly characterized entity, immune mechanism, assessment and management remaining still unclear. The aim of this study was to investigate endothelial and inflammatory cells activation in RM muscle biopsy. MATERIAL AND METHODS: Prospective study on 23 consecutive rheumatoid arthritis (RA) with muscle involvement as defined by clinical, biological and imagistic parameters. CD4, CD8, CD20, CD3, CD45RO and CD68 markers, HLA-DR, cytokines receptors (IL-2, TNFalpha, TGF alpha), pro-apoptotic (CD95) and adhesion molecules (CD54) were assessed by immunohistochemistry in deltoid muscle samples. RESULTS: (1) endomysial, perivascular and perimysial inflammatory infiltrates and moderate muscle fibers involvement; predominance of activated (HLA-DR+), memory (CD45RO+) CD3+TCD8+ cells and macrophages surrounding and invading non-necrotic muscle fibers (34.78%) and TCD4+ activated cells in perivascular and perifascicular areas (65.22%); (2) up-regulation of HLA-DR, CD54 and IL-2R on both endothelial cells and lymphocytes (85%); (3) aberrant increased CD95 in endothelial cells without any other apoptotic sign (83%) have been described. CONCLUSION: Increased expression of activation markers, adhesion molecules and cytokine receptors may indicate early endothelial activation in RM pathogenesis, while endomysial TCD8+ activation may account for further development and perpetuation of myositis.
19296831 The health-related quality of life in rheumatoid arthritis, ankylosing spondylitis, and ps 2009 Mar 18 BACKGROUND: The health-related quality of life (HRQL) is an important indicator of the burden of musculoskeletal disease. The Medical Outcome Study Short-Term 36 (SF-36) is the most used tool that evaluates HRQL as a subjective perception about psychological and physical limitations due to an underlying illness. The purpose of this study was to compare the HRQL scores among patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and ankylosing spondylitis (AS) and a selected sample of health people and determine their relationship with measures of clinical condition. METHODS: 799 patients (469 with RA, 164 with AS, 65 with axial PsA and 101 with peripheral PsA) accepted the invitation to participate. 1579 healthy controls were used for the comparison. We calculated scores for the eight SF-36 subscales, the Physical Component Summary (PCS) score, and the Mental Component Summary (MCS) score, according to published algorithms. Disease-related characteristics included disease duration, comorbidity, a measure for disease activity and for radiographic damage. The presence of comorbidity was ascertained through patient's self-reports by the Self-Administered Comorbidity Questionnaire (SCQ). Comparison were performed with respect to sex and age, and s-scores were calculated for comparison with the norm. Multivariate analyses were used to assess the relationship between HRQL and radiographic damage, disease activity, and socio-demographic data. RESULTS: The four inflammatory rheumatic diseases (IRD), compared to controls, significantly impaired all eight health concepts of the SF-36 (p < 0.0001) in both component PCS and MCS scores (p < 0.0001). Overall, the dimensions typically affected were physical functioning, limitations due to physical function, and bodily pain. The disease with the worst HRQL for those dimensions was RA. The multivariate analyses revealed that the physical component was influenced by a high disease activity and comorbidity. The severity of psoriatic lesions was associated with poor mental functioning in patients with PsA. CONCLUSION: Chronic IRD have a clearly detrimental effect on the HRQL in both sex and in age groups, and physical domain is more impaired than mental and social ones.
19880281 The use of an item response theory-based disability item bank across diseases: accounting 2010 May OBJECTIVE: There is not a single universally accepted activity of daily living (ADL) instrument available to compare disability assessments across different patient groups. We developed a generic item bank of ADL items using item response theory, the Academic Medical Center Linear Disability Scale (ALDS). When comparing outcomes of the ALDS between patients groups, item characteristics of the ALDS should be comparable across groups. The aim of the study was to assess the differential item functioning (DIF) in a group of patients with various disorders to investigate the comparability across these groups. STUDY DESIGN AND SETTING: Cross-sectional, multicenter study including 1,283 in- and outpatients with a variety of disorders and disability levels. The sample was divided in two groups: (1) mainly neurological patients (n=497; vascular medicine, Parkinson's disease and neuromuscular disorders) and (2) patients from internal medicine (n=786; pulmonary diseases, chronic pain, rheumatoid arthritis, and geriatric patients). RESULTS: Eighteen of 72 ALDS items showed statistically significant DIF (P<0.01). However, the DIF could effectively be modeled by the introduction of disease-specific parameters. CONCLUSION: In the subgroups studied, DIF could be modeled in such a way that the ensemble of the items comprised a scale applicable in both groups.
20974613 Inter-observer reliability of high-resolution ultrasonography in the assessment of bone er 2011 Feb OBJECTIVE: The present study was aimed at testing the ability of a rheumatologist without experience in ultrasound (US) who attended an intensive 4-week training programme focused on US assessing bone erosions in the hands and feet in patients with RA. METHODS: Twenty patients diagnosed with RA according to the ACR criteria were included in the study. All US examinations were performed bilaterally by two investigators (with different experience in the field of musculoskeletal US) at the following sites: the dorsal, lateral and volar aspect of the second metacarpal, ulnar and fifth metatarsal head; and the dorsal and volar aspect of the third metacarpal and second proximal heads. Each quadrant was scanning in longitudinal and transverse scans for assessing the qualitative, semiquantitative and quantitative US findings indicative of bone erosions according the OMERACT preliminary definition. RESULTS: Both κ-values and overall agreement percentages of qualitative and semiquantitative assessments showed moderate to excellent agreement between the two investigators. Similar results were obtained for the quantitative assessment with the concordance correlation coefficient value always significant. The only exception was the volar aspects, in particular those of the fifth metatarsal head. CONCLUSION: Our study suggests that after a 4-week dedicated training programme, a rheumatologist without experience in US is able to detect and score bone erosions in the hands and feet of patients with RA.
20975633 Tocilizumab - a new step in rheumatoid arthritis treatment. 2010 Jul Rheumatoid Arthritis is a chronic systemic inflammatory disease characterized by joint pain, stiffness and swelling, with progressive destruction of small joints of the hands and feet. Methotrexate remains the most commonly used therapy and has been the recommended standard against which new drugs should be evaluated and, to date, there is limited evidence that monotherapy with other treatments is superior to MTX. The introduction of biologic agents, such as TNFα-antagonists, represented an advance in the treatment of RA. However, there are still patients with no or inadequate response, patients in whom responsiveness to treatment is lost over time, and patients in whom safety issues may develop. Thus, patients may benefit from treatment with newer biologic agents with a different mechanism of action. Tocilizumab is an IL-6 receptor inhibitor which shows significant (and rapid) clinical efficacy in the treatment of Rheumatoid Arthritis patients, as assessed by ACR responses and DAS remission rates, with an acceptable safety profile.
19132785 Determination of the subset of Sjogren's syndrome with articular manifestations by anticyc 2009 Jan OBJECTIVE: To investigate whether anticyclic citrullinated peptide antibodies (anti-CCP) predict the subset of Japanese patients with Sjögren's syndrome (SS) with articular manifestations. METHODS: Eighty-seven patients with SS were enrolled. Prevalence of anti-CCP antibodies, IgM rheumatoid factor, anti-Ro/SSA antibody, anti-La/SSB antibody, and serum IgG concentration and their relation to articular manifestations were examined. Articular manifestations included morning stiffness and the presence of tender or swollen joints. RESULTS: Eighty-seven SS patients were divided into 3 groups: 14 secondary SS with nonerosive rheumatoid arthritis (RA); 47 primary SS with articular manifestations; and 26 primary SS without articular manifestations. Ten out of 14 secondary SS with nonerosive RA expressed anti-CCP. Anti-CCP was the only statistically proven marker preferentially distributed in patients with articular manifestations (the first 2 groups) compared to primary SS without such manifestations; however, its frequency was low in primary SS. No patient with primary SS without articular manifestations expressed anti-CCP. CONCLUSION: Anti-CCP is found in the subset of Japanese with SS with articular manifestations although most of those with anti-CCP-positive SS were classified as secondary SS with RA.
20721560 Synovial fluid adenosine deaminase and high-sensitivity C-reactive protein activity in dif 2012 Jan It is proposed that synovial fluid biomarkers may help in differentiating the type of arthritis. The aim of study is to determine whether synovial fluid adenosine deaminase (ADA) and high-sensitivity C-reactive protein (hs-CRP) can be useful in this regard. A total of 75 patients with knee monoarthritis that were admitted in Shahid Beheshti Kashan hospital in 2009 included in the study. There were 18 rheumatoid arthritis, 13 crystal-induced arthritis, 3 septic arthritis and 41 osteoarthritis. Inflammatory arthritis was diagnosed if more than 2,000 white blood cells existed in per milliliter of the synovial fluid. There was statistically significant difference in mean synovial fluid ADA and hs-CRP concentration between inflammatory (26.06 ± 8.96 IU/l, 12.72 ± 9.25 μg/ml) and non-inflammatory arthritis (14.8 ± 2.79 IU/l, 2.36 ± 2.7 μg/ml) (P values = 0.00, 0.00). There was statistically significant difference in mean synovial fluid ADA and hs-CRP concentration when rheumatoid arthritis (23.77 ± 4.58 IU/l, 10.47 ± 6.99 μg/ml), crystal-induced arthritis (22.76 ± 3.65 IU/l, 14.37 ± 11.58 μg/ml) and septic arthritis (49.66 ± 8.96 IU/l, 18.25 ± 5.37 μg/ml) were compared with osteoarthritis (14.58 ± 2.63 IU/l, 1.91 ± 1.31 μg/ml) (All P values = 0.00). There was statistically significant difference in mean synovial fluid ADA concentration between septic and rheumatoid arthritis and also between septic arthritis and crystal-induced arthritis (P values = 0.00, 0.00). This study showed that synovial fluid ADA and hs-CRP can properly differentiate inflammatory from non-inflammatory arthritis. Synovial fluid ADA is a useful marker in differentiating septic from rheumatoid and crystal-induced arthritis.
21058483 [Effects of electroacupuncture and simple acupuncture on changes of IL-1, IL-4, IL-6 and I 2010 Oct OBJECTIVE: To explore the mechanism of electroacupuncture on rheumatoid arthritis (RA). METHODS: In a randomized and controlled trial, sixty-three cases with RA were randomly divided into an electroacupuncture group (n = 32) and a simple acupuncture group (n = 31). Baihui (GV 20), Fengchi (GB 20), Quchi (LI 11), Waiguan (TE 5), Guanyuan (CV 4) and Zusanli (ST 36) were selected by coordination method combined whole and local acupoints. The electroacupuncture group was treated with electroacupuncture at the local acupoints near painful joints, continuous wave, retaining needle for 30 minutes, and then electroacupuncture at Back-shu acupoints, retaining needle for 15 minutes, and the simple acupuncture group was treated with the same acupoints selection and acupuncture manipulation without electroacupuncture apparatus. They were all treated once every other day for 20 days as one course. After 3 courses, changes of interleukins in peripheral blood and joint fluid of patients were observed. RESULTS: Both of electroacupuncture and simple acupuncture had significant effect on IL-1, IL-4, IL-6 and IL-10 in peripheral blood and joint fluid of patients with RA ( P < 0.01, P < 0.05). But after electroacupuncture, the absolute value and improvement value of decreasing IL-1 in peripheral blood and joint fluid were super than those of simple acupuncture (all P < 0.05), and of IL-4 in joint fluid was super than that after simple acupuncture (P < 0.05), and of IL-6 and the absolute value of decreasing IL-10 were almost the same after both treatment (all P > 0.05), and after electroacupuncture, the improvement value of IL-10 in peripheral blood and joint fluid were super than those after simple acupuncture (both P < 0.05). CONCLUSION: Electroacupuncture can effectively decrease the proinflammatory cytokine of IL-1 and IL-6 and increase the inhibition cytokine of IL-4 and IL-10 and improve the internal environment of occurrence and progression of RA.
19095181 Methodological properties of six shoulder disability measures in patients with rheumatic d 2009 Jan The aim of this study was to explore the methodological properties in 6 commonly used shoulder disability measures (Dash, Spadi, Oxford, the Constant score, Shoulder Function Assessment Scale, Bostrom's shoulder movement impairment scale) in patients with inflammatory or degenerative diseases referred for shoulder surgery. One-hundred and six patients completed the measures preoperatively. Fifty-five (51.9%) were not able to carry out the assessment of the strength component of the Constant score. Pearson correlation coefficients between the measures varied between 0.22 and 0.87. The lowest correlation coefficients were found between performance-based and self-report measures. All measures, except the Dash, were able to differentiate significantly between patients who were more and less severely affected. Performance-based measures differentiated better (effect size, 0.68- 0.87) than self-report measures (effect size, 0.21-0.61) between the 2 patient groups. Performance-based and self-report assessments provide complementary information about shoulder status and should not be used interchangeably.
19252250 [Effect of disease modifying anti-rheumatic drugs on radiographic progression in rheumatoi 2009 Mar Because of a paradigm shift in the therapeutic strategy of RA by biologics, the goal of RA therapy became not only the clinical remission, but also the imaging remission. From the results of randomized controlled clinical trials of disease modifying anti-rheumatic drugs (DMARDs), decreased radiographic progression has been documented. In particular, methotrexate (MTX) is described as "anchor drug" of RA therapy because inhibitory effects of MTX on radiographic progression are proved by many clinical trials. Although DMARDs can slow down the radiographic progression with the achievement of clinical remission in RA, some patients still have subclinical synovitis detected by imaging technique. Such subclinical inflammation may explain the observed discrepancy between disease activity and radiographic progression in RA during DMARD therapy.
21059672 Gene profiling predicts rheumatoid arthritis responsiveness to IL-1Ra (anakinra). 2011 Feb OBJECTIVES: The overall non-response rate to biologics remains 30-40% for patients with RA resistant to MTX. The objective of this study was to predict responsiveness to the anakinra-MTX combination by peripheral blood mononuclear cell gene profiling in order to optimize treatment choice. METHODS: Thirty-two patients treated with anakinra (100 mg/day s.c.) and MTX were categorized as responders when their 28-joint DAS (DAS-28) had decreased by ≥1.2 at 3 months. Pre-treatment blood samples had been drawn. RESULTS: For seven responders and seven non-responders, 52 microarray-identified mRNAs were expressed as a function of the response to treatment, and unsupervised hierarchical clustering correctly separated responders from non-responders. The levels of seven of these 52 transcripts, as assessed by real-time, quantitative RT-PCR, were able to accurately classify 15 of 18 other patients (8 responders and 10 non-responders), with 87.5% specificity and 77.8% negative-predictive value for responders. Among the 52 genes, 56% were associated with IL-1β. CONCLUSION: This predictive gene expression profile was obtained with a non-invasive procedure. After further validation in other cohorts of patients, it could be proposed and used on a large scale to select likely RA responders to combined anakinra-MTX. Trial registration. Clinical Trials; NCT00213538 (http://www.clinicaltrials.gov).
19052835 Necrotising scleritis and connective tissue disease--three cases and a review. 2009 Mar Necrotising scleritis is a severe form of anterior scleritis which is known to be associated with connective tissue disease but has not previously been reported in association with limited scleroderma. It is often a difficult condition to treat and without adequate early intervention leads to significant morbidity including visual loss. We report three cases of necrotising scleritis, two occurring in the context of previously unreported associations and a third case to compare presentation of the condition and highlight difficulties in management.
20216124 Trough infliximab concentrations predict efficacy and sustained control of disease activit 2010 Apr Infliximab is a chimeric monoclonal antibody that binds to human tumor necrosis factor alpha and is approved for refractory rheumatoid arthritis. We studied the association between infliximab concentration and long-term control of disease activity in patients with rheumatoid arthritis treated on a routine basis both in cross-sectional analysis and over the long term. Trough serum infliximab concentrations were measured in patients with rheumatoid arthritis receiving infliximab infusions during the period August to October 2006. Disease activity was assessed by the Disease Activity Score for 28 Joints (DAS28) and usual biologic markers. During a 42-week follow-up period, patients were classified into two groups: those continuing with the same or lower doses of infliximab (Group A = treatment success) and those who switched to another biopharmaceutical or required an increase in infliximab dose (Group B = treatment failure). Treatment maintenance for Group A was analyzed by categories of infliximab concentration at baseline and compared by the log rank test. In 28 patients, C-reactive protein and infliximab concentrations were inversely related. Infliximab concentration in patients with low disease activity (DAS28 3.2 or less) was higher than in those with persistent active disease (DAS28 greater than 3.2); median values were 3.26 and 0.16 mg/L, respectively (P < 0.01). Analysis after 42 weeks showed that patients in Group A had higher infliximab concentrations at baseline than those with treatment failure (P < 0.01). In rheumatoid arthritis, infliximab concentration is predictive of sustained efficacy with the same infliximab regimen and should be considered on a routine basis.
19445983 Thrombin-sensitive photodynamic agents: a novel strategy for selective synovectomy in rheu 2009 Sep 15 Protease-sensitive macromolecular prodrugs have attracted interest for bio-responsive drug delivery to sites with up-regulated proteolytic activities such as inflammatory or cancerous lesions. Here we report the development of a novel polymeric photosensitizer prodrug (T-PS) to target thrombin, a protease up-regulated in synovial tissues of rheumatoid arthritis (RA) patients, for minimally invasive photodynamic synovectomy. In T-PS, multiple photosensitizer units are tethered to a polymeric backbone via short, thrombin-cleavable peptide linkers. Photoactivity of the prodrug is efficiently impaired due to energy transfer between neighbouring photosensitizer units. T-PS activation by exogenous and endogenous thrombin induced an increase in fluorescence emission by a factor of 16 after in vitro digestion and a selective fluorescence enhancement in arthritic lesions in vivo, in a collagen-induced arthritis mouse model. In vitro studies on primary human synoviocytes showed a phototoxic effect only after enzymatic digestion of the prodrug and light irradiation, thus demonstrating the functionality of T-PS induced PDT. The developed photosensitizer prodrugs combine the passive targeting capacity of macromolecular drug delivery systems with site-selective photosensitizer release and activation. They illuminate lesions with pathologically enhanced proteolytic activity and induce cell death, subsequent to irradiation.
20435922 Resolution of inflammation in murine autoimmune arthritis is disrupted by cyclooxygenase-2 2010 Jun 1 Acute inflammation follows defined phases of induction, inflammation and resolution, and resolution occurs by an active process that requires cyclooxygenase-2 (COX-2) activity. This study aims to address whether this paradigm extends to recognized model of chronic inflammation. We demonstrated that murine collagen-induced arthritis follows a similar sequential course. Interestingly, COX-2 and its metabolite, the presumably proinflammatory PGE(2), are present in the joints during resolution, and blocking COX-2 activity and PGE(2) production within this period perpetuated, instead of attenuated, inflammation. Repletion with PGE(2) analogs restored homeostasis, and this function is mediated by the proresolving lipoxygenase metabolite, lipoxin A(4), a potent stop signal. Thus, the study provided in vivo evidence for a natural, endogenous link between the cyclooxygenase-lipoxygenase pathways and showed that PGE(2) serves as a feedback inhibitor essential for limiting chronic inflammation in autoimmune arthritis. These findings may explain the enigma regarding why COX-2 inhibitors are palliative rather than curative in humans, because blocking resolution may mitigate the benefit of preventing induction.
21109513 Cardiovascular disease in rheumatoid arthritis: state of the art and future perspectives. 2011 Jan Rheumatoid arthritis is associated with an increased risk for cardiovascular events, such as myocardial infarction and stroke. Epidemiological evidence suggests that classic cardiovascular risk factors, such as hypertension, dyslipidaemia, insulin resistance and body composition alterations are important but not sufficient to explain all of the excess risk. High-grade systemic inflammation and its interplay with classic risk factors may also contribute. Some associations between classic risk factors and cardiovascular risk in people with rheumatoid arthritis appear counterintuitive but may be explained on the basis of biological alterations. More research is necessary to uncover the exact mechanisms responsible for this phenomenon, develop accurate systems used to identify patients at high risk, design and assess prevention strategies specific to this population of patients.
19939280 Infliximab concentration monitoring improves the control of disease activity in rheumatoid 2009 INTRODUCTION: Adjustment of infliximab dosage for individuals may be useful in improving therapeutic response in rheumatoid arthritis (RA). Herein, we aimed to determine whether measurement of infliximab serum concentration modifies the therapeutic decision and improves the control of disease activity. METHODS: RA patients routinely treated with infliximab were included in an observational open-label study. On visit 1 (V1), according to the disease activity, a preliminary therapeutic decision was selected among four therapeutic options and a blood sample was collected to measure trough serum infliximab concentration. The final therapeutic decision, based on both disease activity and serum infliximab concentration assessed at V1, was applied at the following infusion (V2). Clinical and biological evaluations were performed at V3 and V4 and compared with those at V1. RESULTS: We included 24 patients. The final therapeutic decision differed from the preliminary decision for 12 patients (50%). For patients with increased infliximab dosage at V2, mean disease activity score for 28 joints (DAS28) decreased by about 20% at V3 or V4 as compared with V1 (P < 0.05). Decreased DAS28 was correlated with increased serum infliximab concentration (P < 0.02). CONCLUSIONS: The measurement of infliximab trough concentration modifies the therapeutic decision for RA patients and helps improve control of disease activity. Therapeutic drug monitoring of infliximab in RA may be useful for individual dosage adjustment.