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ID PMID Title PublicationDate abstract
29352092 Incident Heart Failure in Patients With Rheumatoid Arthritis: A Nationwide Cohort Study. 2018 Jan 19 BACKGROUND: Rheumatoid arthritis (RA) is a chronic inflammatory disease associated with a wide range of comorbidities, including cardiovascular disease, but its association with heart failure (HF) is not fully clear. We investigated the risk of incident HF in a nationwide cohort of patients with RA. METHODS AND RESULTS: The study comprised the entire Danish population aged ≥18 years followed from January 1, 2008 until first hospitalization for HF, emigration, December 31, 2012, or death. Information on comorbidity, medication, and socioeconomic status was identified by individual-level linkage of administrative registers. Patients with a rheumatologist diagnosis of RA between 1978 and 2008 were included. The primary study outcome was incident HF defined as first hospital admission for HF. Incidence rates of HF per 1000 person-years were calculated and incidence rate ratios adjusted for age, sex, calendar year, comorbidity, medications, socioeconomic status, smoking, and alcohol consumption were estimated. A total of 4 305 225 subjects with no history of HF were eligible for analysis at the study start. Of these subjects, 24 343 developed RA and 50 623 were hospitalized for HF. Overall incidence rates of incident HF were 2.43 and 6.64 for the reference population (n=49 879) and patients with RA (n=744), respectively. Correspondingly, the fully adjusted incidence rate ratio for incident HF was increased in patients with RA with incidence rate ratio 1.30 (95% confidence interval, 1.17-1.45). CONCLUSIONS: In this cohort study, RA was associated with an increased hospitalization for HF. These findings add significantly to the existing evidence of RA as a clinically relevant risk factor for HF.
29225253 An Analysis of the Neuropathic Pain Components in Rheumatoid Arthritis Patients. 2018 Feb 15 Objective To analyze the neuropathic pain (NeP) components in patients with rheumatoid arthritis (RA). Methods The painDETECT questionnaire (PD-Q) was completed by 300 RA patients (79 men, 221 women). Results Nine patients (3.0%) were categorized as likely NeP, 33 (11.0%) were categorized as possible NeP, and 258 (86.0%) were categorized as unlikely NeP. When we excluded patients with diabetes mellitus, spinal diseases, neurological diseases, and herpes zoster infection (conditions associated with NeP), 5 of the patients (1.7%) had likely NeP, and 23 (7.7%) had possible NeP without any underlying conditions. Furthermore, there were no marked differences in the percentages of these underlying conditions among the patients with likely, possible, and unlikely NeP. When we compared patients with likely and possible NeP (n=42) and unlikely NeP (n=258), the body mass index (BMI), disease activity score-28 based on the erythrocyte sedimentation rate, C-reactive protein level, pain visual analogue scale (VAS), and PD-Q score were significantly higher in the patients with likely and possible NeP than in those with unlikely NeP. A multivariate analysis showed that BMI ≥22 and not being in clinical remission were associated with NeP. Conclusion Although RA pain has usually been classified as nociceptive pain, the present study clarified that a significant number of patients might have NeP. The present findings suggest that high disease activity and being overweight are related to NeP in RA patients.
30511295 MicroRNA-132, miR-146a, and miR-155 as potential biomarkers of methotrexate response in pa 2019 Mar INTRODUCTION: Rheumatoid arthritis (RA) patients have high expression levels of hsa-miR-132-3p, hsa-miR-146a-5p, and hsa-miR-155-5p in peripheral blood. We studied if baseline blood levels of these microRNAs (miRNAs) could predict response to methotrexate (MTX). METHODS: RA patients (the American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) criteria) with active disease (disease-modifying anti-rheumatic drug (DMARD)-naïve and Disease Activity Score 28 (DAS28) > 3.2) were enrolled. They were treated with MTX by gradually increasing dose up to 25 mg/week. After 4 months, the DAS28 score was calculated and EULAR response was assessed. The hsa-miR-132-3p, hsa-miR-146a-5p, and hsa-miR-155-5p levels were measured by real-time qPCR in whole-blood RNA at baseline and 4 months after therapy, using hsa-let-7a-5p as housekeeping gene. Results are expressed as median (interquartile range). RESULTS: The 94 enrolled patients (81 females) had a median age of 40 (17) years, disease duration of (24) months, and DAS28 4.61 (1.11). After 4 months of therapy, 73 were classified as responders and 21 as non-responders. Baseline levels of all three miRNAs were lower in responders than non-responders, hsa-miR-132-3p (- 8.03 (0.70) versus - 7.47 (0.85), P < 0.05), hsa-miR-146a-5p (- 5.11 (0.88) versus - 4.62 (0.90), P < 0.05), and hsa-miR-155-5p (- 7.59 (1.07) versus - 7 (0.72), P = 0.002). Receiver operating characteristic curve analysis showed that all three miRNAs were also good predictors of MTX response, showing the following values: hsa-miR-132-3p (area under curve (AUC) 0.756, P < 0.05), hsa-miR-146a-5p (AUC 0.760, P < 0.05), and hsa-miR-155-5p (AUC 0.728, P = 0.002). CONCLUSION: hsa-miR-132-3p, hsa-miR-146a-5p, and hsa-miR-155-5p are potential biomarkers of responsiveness to MTX therapy.
29793335 Ziziphora clinopodioides ameliorated rheumatoid arthritis and inflammatory paw edema in di 2018 Jan Ziziphora clinopodioides has been used in traditional medicine for its anti-inflammatory properties. Current study is believed to first time report the potential of Z. clinopodioides extracts to ameliorate joint inflammation using model of chronic joint inflammation (FCA-induced rheumatoid arthritis). The study further investigates the effects on joint inflammation using acute inflammatory paw edema models. The anti-inflammatory effects were also supported by using xylene-induced ear edema model. Results showed that Z. clinopodioides significantly ameliorated rheumatoid arthritis as indicated by the inhibition of arthritic development and paw edema. Histopathological examination showed significant attenuation in pannus formation, bone erosion, and joint inflammation. Treatment with the plant extracts also nearly normalized counts of RBCs, platelets, and total leukocytes along with hemoglobin (Hb) content. Biochemical analysis (AST, ALT, urea, and creatinine) showed that plant extracts did not possess hepatotoxic or nephrotoxic effects. Water displacement plethysmometric analysis showed that Z. clinopodioides significantly attenuated carrageenan-induced paw edema. To evaluate the mechanism, anti-inflammatory effects were further evaluated using histamine- and serotonin-induced inflammatory paw edema models. Z. clinopodioides significantly suppressed paw edema induced by both histamine and serotonin, and also caused the inhibition of xylene-induced ear edema. This suggested the inhibition of autacoids as one of the mechanisms of anti-inflammatory effects of plant. GC-MS analysis showed that the plant is rich in essential oils, including terpenoids, esters, alcohols, furans, cyclic ketones, epoxides, oxanes, and acyclic hydrocarbons. In conclusion, current study demonstrated that Z. clinopodioides possessed significant anti-arthritic and anti-inflammatory properties which might be attributed to the inhibition of autacoids.
29327123 Text Mining of Rheumatoid Arthritis and Diabetes Mellitus to Understand the Mechanisms of 2018 Oct OBJECTIVE: To identify the commonalities between rheumatoid arthritis (RA) and diabetes mellitus (DM) to understand the mechanisms of Chinese medicine (CM) in different diseases with the same treatment. METHODS: A text mining approach was adopted to analyze the commonalities between RA and DM according to CM and biological elements. The major commonalities were subsequently verified in RA and DM rat models, in which herbal formula for the treatment of both RA and DM identified via text mining was used as the intervention. RESULTS: Similarities were identified between RA and DM regarding the CM approach used for diagnosis and treatment, as well as the networks of biological activities affected by each disease, including the involvement of adhesion molecules, oxidative stress, cytokines, T-lymphocytes, apoptosis, and inflammation. The Ramulus Cinnamomi-Radix Paeoniae Alba-Rhizoma Anemarrhenae is an herbal combination used to treat RA and DM. This formula demonstrated similar effects on oxidative stress and inflammation in rats with collagen-induced arthritis, which supports the text mining results regarding the commonalities between RA and DM. CONCLUSION: Commonalities between the biological activities involved in RA and DM were identified through text mining, and both RA and DM might be responsive to the same intervention at a specific stage.
29529307 Opportunistic infections in rheumatoid arthritis patients exposed to biologic therapy: res 2018 Jun 1 OBJECTIVES: This analysis set out to estimate the risk of opportunistic infection (OI) among patients with RA by biologic class. METHODS: The British Society for Rheumatology Biologics Register for Rheumatoid Arthritis is a prospective observational cohort study established to evaluate safety of biologic therapies. The population included adults commencing biologic therapy for RA. The primary outcome was any serious OI excluding tuberculosis (TB). Event rates were compared across biologic classes using Cox proportional hazards with adjustment for potential confounders identified a priori. Analysis of the incidence of TB was performed separately. RESULTS: In total, 19 282 patients with 106 347 years of follow-up were studied; 142 non-TB OI were identified at a rate of 134 cases/100 000 patient years (pyrs). The overall incidence of OI was not significantly different between the different drug classes; however, the rate of Pneumocystis infection was significantly higher with rituximab than with anti-TNF therapy (adjusted hazard ratio = 3.2, 95% CI: 1.4, 7.5). The rate of TB fell dramatically over the study period (783 cases/100 000 pyrs in 2002 to 38 cases/100 000 pyrs in 2015). The incidence of TB was significantly lower among rituximab users than anti-TNF users, with 12 cases/100 000 pyrs compared with 65 cases/100 000 pyrs. CONCLUSIONS: The overall rate of OI was not significantly different between drug classes; however, a subtle difference in the pattern of OI was seen between the cohorts. Patient factors such as age, gender and comorbidity were the most important predictors of OI.
30657096 Characterization of falls in adults with established rheumatoid arthritis and associated f 2018 Jul 27 BACKGROUND: Rheumatoid arthritis patients may have an increased risk of falls due to changes caused by the disease such as muscle weakness, joint impairment, reduced mobility and postural instability. The aim of this study was to prospectively analyze the occurrence of falls in RA patients and its risk factors. METHODS: A cohort of 86 RA patients were assessed over 1 year for disease activity using the Disease Activity Score (DAS-28), for functionality using the Health Assessment Questionnaire (HAQ), for the characterization of falls and for the use of medications, and they were subjected to the Berg Balance Scale (Berg), Timed Up and Go (TUG), 6-Minute Walk (6MWT) and Short Physical Performance Battery (SPPB) tests. The Kolmogorov-Smirnov, Spearman's correlation, Student's t, Mann-Whitney and chi-square tests were performed with a significance level of P ≤ 0.05. RESULTS: A total of 86 patients were evaluated, of which 48.8% had at least one fall and 75.6% reported having a fear of falling. No association of falls with age, disease duration, functional capacity, disease activity or physical performance was found. Patients with poorer performance in the physical tests had more functional impairment, higher disease activity and more advanced age. No differences in physical or functional performance, disease activity, gender or fear of falling were found between fallers and non-fallers; only a greater amount of medications used was found in the group of fallers. CONCLUSIONS: The occurrence of falls was high and associated with a previous history of falls and polypharmacy, with no association with disease activity or duration, functional capacity, physical performance, age or gender.
29731452 [Diagnosis and treatment of rheumatoid arthritis:toward the best practice. Pathogenesis of 2018 Rheumatoid arthritis(RA)has been a disease of unknown cause for many years. However, the etiology is becoming obvious due to the use of biological products in recent years, arthritis model mice in basic immunology and genome wide analysis in genetics etc. In particular, the knowledge of what is effective and what is not effective for biological products directly reveals the pathology of RA. It has also been found that the cytokine dependence of arthritis model mice and RA is not necessarily the same. It is pointed out that the difference may be derived from the presence of anti-citrullinated protein antibody(ACPA). Studies of immune responses against self antigens such as citrullinated protein will provide a clue to elucidate the pathogenesis of RA. Further analysis of genetic polymorphism and epigenome in combination with human immunity is expected to promote understanding of RA.
30450972 Is dry heat treatment (fluidotherapy) effective in improving hand function in patients wit 2019 Mar OBJECTIVE: To evaluate the efficacy of dry heat treatment (fluidotherapy) in improving hand function in patients with rheumatoid arthritis. DESIGN: Prospective randomized controlled trial. SETTING: Departments of Physical Medicine and Rehabilitation and Rheumatology in a university hospital. SUBJECTS: Patients with rheumatoid arthritis. INTERVENTIONS: All patients were randomly divided into two groups. Group 1 underwent dry heat treatment (fluidotherapy) and Group 2 was a control group. Patients in both groups participated in a joint protection and exercise program. MAIN MEASURES: Primary outcome measures were Health Assessment Questionnaire and Duruoz Hand Index. Secondary outcome measures were pain and stiffness, Grip Ability Test, Disease Activity Score-28, and grip strength. These assessments were performed at the hospital at baseline, week 3, and week 12. RESULTS: A total of 93 participants were allocated to Group 1 ( n = 47) and Group 2 ( n = 46). The mean age of these groups was 54.19 ± 11.15 years and 53.00 ± 10.15 years, respectively ( P = 0.592). At baseline, there were no significant differences between the groups in any parameter except significantly poorer Health Assessment Questionnaire score in Group 1 ( P = 0.007). At week 3, there were no significant differences between the groups in any of the parameters ( P > 0.005). At week 12, Duruoz Hand Index scores were significantly better in Group 2 ( P = 0.039). CONCLUSION: Dry heat treatment (fluidotherapy) was not effective in improving hand function in patients with rheumatoid arthritis. Moreover, no positive effect on any other clinical parameters was observed.
29481732 Ultrasonographic Efficacy of Biologic and Targeted Synthetic Disease-Modifying Antirheumat 2018 Dec OBJECTIVE: To explore the variables associated with initial favorable power Doppler (PD) ultrasound (US) response induced by biologic and targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs) in patients with rheumatoid arthritis (RA). METHODS: We have been prospectively investigating the course of active RA patients using US after the introduction of b/tsDMARDs in the Kyushu region of Japan since June 2013. A total of 150 patients have completed the first 6 months of observation at present and have been evaluated. US was assessed in 22 joints of bilateral hands using gray-scale and PD images on a scale from 0-3. The sum of these scores was used as the indicator of US disease activity. We defined PD remission as attaining a total PD score of 0 at 6 months and investigated the associated variables by multivariate logistic regression analysis. RESULTS: The total PD and gray-scale scores and the clinical composite measures significantly improved at 6 months, whereas these reductions were less in bDMARD switchers as compared with bDMARD-naive patients. Multivariate logistic regression analysis showed that short disease duration, the absence of any previous use of bDMARDs, and low total PD scores at baseline were independent predictors of PD remission at 6 months. CONCLUSION: This present prospective US cohort has for the first time shown the variables that are associated with initial PD response to b/tsDMARDs.
30039721 They have got the blues: patient's mood- and disease activity-related psychological burden 2019 Jun Objective: Rheumatoid arthritis (RA), as a long-lasting disease, not only affects the musculoskeletal health but also deteriorates the psychological well-being of the patient. What about their caregivers? There exist a limited number of studies on this issue. The objectives of the present study were (i) to evaluate the psychological health among caregivers of RA patients and (ii) to determine the confounding factors playing role on their psychological status. Methods: Fifty-three RA patients and their caregivers were included in this cross-sectional study. Disease activity was assessed by using the disease activity score 28 based on C-reactive protein (DAS28-CRP) and rheumatoid arthritis disease activity index-5 (RADAI-5), while disability was evaluated by disability of the arm, shoulder, and hand (DASH) questionnaire. Psychological status was tested by Beck's depression and anxiety inventories (BDI and BAI). Results: A total of 53 patients with RA were included in the study. Caregivers' depression score was weakly correlated with disease activity variables including DAS28-CRP, RADAI and DASH scores (rs = .304, rs = .392 and rs = .301, respectively); and moderately correlated with patients' depression score and caregivers' comorbidity (rs = .407 and rs = .451, respectively). Conclusions: The psychological impact of RA on caregivers appears to be associated with patients' mood, disease activity and upper extremity functionality.
30244472 Assessment of Disease Activity, Structural Damage, and Function in Rheumatoid Arthritis. 2018 The primary goal in the treatment of rheumatoid arthritis (RA) should be achieving control of disease activity, prevention of structural damage in joints, and normalization of function. Therefore, reliable tools are necessary to evaluate RA. Here, we describe methods recently used to assess RA.
30097553 Rheumatoid leptomeningitis presenting with an acute neuropsychiatric disorder. 2019 Feb Leptomeningitis is a rare central nervous system manifestation of rheumatoid arthritis, generally in patients with established chronic rheumatoid disease. We report a 41-year-old man without previous rheumatoid arthritis or psychiatric disorder who presented with an acute neuropsychiatric disturbance and polyarthralgia. His MR scan of brain showed asymmetric bifrontal leptomeningitis, confirmed on (18F)-fluoro-D-glucose-positron emission tomography. Other investigations showed highly positive serum and cerebrospinal fluid anti-cyclic citrullinated peptide. A leptomeningeal biopsy showed necrotising leptomeningeal inflammation with ill-defined granulomas and lymphoplasmacytic infiltrate without organisms. Prolonged high-dose corticosteroids and then rituximab resulted in recovery. Chronic leptomeningitis can present with an acute neuropsychiatric disorder. We highlight that early rheumatoid disease can, rarely, cause a chronic leptomeningitis, reversible with immunotherapy.
30196708 Changes in Care After Implementing a Multifaceted Intervention to Improve Preventive Cardi 2019 May Rheumatoid arthritis (RA) increases cardiovascular disease (CVD) risk. However, CVD risk factor identification and treatment is often inadequate. The authors implemented a multifaceted rheumatology practice intervention to improve CVD risk factor measurement, assessment, and management. The intervention included clinician education, point-of-care decision support, feedback, and care management. The authors measured quality indicators from electronic health records and assessed impact with interrupted time series. Following the intervention, more RA patients had all major CVD risk factors assessed (53% vs 72.2%), and the rate of increase was greater during the intervention period than baseline (difference of 0.74% per month, P = .0016). Moderate- or high-intensity statin prescribing increased (21.6% to 28.2%), but the rate of change was not different from baseline. Several other quality measures did not increase. Although CVD risk factor assessment improved, the intervention did not affect risk factor management and control. Other strategies are needed to optimize CVD prevention in RA.
29461231 EFFICIENCY OF BIOFEEDBACK THERAPY IN COMPLEX TREATMENT OF RHEUMATOID ARTHRITIS PATIENTS. 2018 Jan Biofeedback is the process of gaining greater awareness of many physiological functions primarily using instruments that provide information on the activity of those same systems, with a goal of being able to manipulate them at will. In this work, the analysis of efficiency of biofeedback therapy in treatment of patients suffering from rheumatoid arthritis (RA) is carried out. This analysis was fulfilled by studying the dynamics of clinical, laboratory and psychological (level of subjective control) indices and their comparison in patients of main and control groups before and after the treatment. During the course of combined therapy alongside biofeedback therapy, an analgesic and anti-inflammatory effects, and improved functional capabilities were noticed in the patients. Thus, the additional use of biofeedback mechanism in complex treatment of RA patients promote increased efficiency of medical and rehabilitation process and improvement of level of self-control in the patients.
29185956 Diagnostic value of BiP or anti-BiP antibodies for rheumatoid arthritis: a meta-analysis. 2018 May OBJECTIVES: To evaluate the diagnostic value of BiP or anti-BiP antibodies in patients with rheumatoid arthritis. METHODS: Relevant studies published on PubMed and CNKI from January 1995 to July 2016 were retrieved. Two reviewers independently evaluated studies and QUADAS tool was used to assess the quality of the included studies. A random-effects model was used to combine sensitivity, specificity, positive and negative likelihood ratios and diagnostic odds ratio. Stratified analysis was performed for exploring heterogeneity and funnel plot was examined for the possibility of publication bias. RESULTS: Nine studies met our inclusion criteria. The pooled sensitivity, specificity, LR+, LR-, DOR were 0.67 (95%CI, 0.64-0.70), 0.92 (95%CI, 0.90-0.93), 7.65(95%CI, 4.08-14.36), 0.36(95%CI, 0.33-0.39), 23.73(95%CI, 13.01-43.28), respectively. CONCLUSIONS: This meta-analysis shows that BiP or anti-BiP antibodies have a moderate accuracy for the diagnosis of rheumatoid arthritis with a moderate sensitivity and high specificity. It can be an efficient supplement to the existing diagnostic method.
29808525 Treatment delays for patients with new-onset rheumatoid arthritis presenting to an Austral 2018 Dec BACKGROUND: Early treatment ensures optimal outcomes in rheumatoid arthritis (RA) yet there are limited data in Australia quantifying treatment delays in clinical practice. AIMS: To quantify treatment delays in new RA patients and to explore factors influencing delay and resultant patient outcomes. METHODS: Data were obtained for 88 patients presenting with a new diagnosis of RA to an early arthritis clinic (EAC) in Australia between 2008 and 2015. Date and details of symptom onset, initial general practitioner (GP) presentation, GP referral and review at EAC were collected. Patient demographics and clinical features were analysed for outcomes and features predictive of delay. RESULTS: Median overall delay from symptom onset to rheumatology review was 26.4 weeks. Patient delay (8.7 weeks) was the longest delay and predicted overall delay. Delays in GP referral and time to EAC review were 4 and 8.4 weeks respectively. Increased overall delay was predicted by lower fatigue and disease activity scores (DAS28) and increased tender joint counts (TJC). Patient delay was increased by socioeconomic disadvantage. Increased GP delay was associated with lower DAS28 and higher TJC and ESR. Patients seen within 16 weeks had greater improvement in DAS28 and probability of remission at 6 months. CONCLUSIONS: In this Australian EAC setting, patient delay was the greatest contributor to RA treatment delay. Delays in treatment were associated with lower disease severity and socioeconomic disadvantage. Remission was more likely after prompt initiation of treatment.
29589645 Chronic peripheral edema in a patient with rheumatoid arthritis. 2018 Mar Chronic peripheral edema is a very common yet underestimated problem. It is of utmost importance to investigate various possible causes and understand the pathophysiological mechanisms of chronic peripheral edema in order to determine the optimal treatment. This case report presents the case of a polymorbid patient with a deformity-causing type of rheumatoid arthritis and a 1-year history of progressive symmetrical peripheral edema. Based on an extensive diagnostic investigation, the patient was diagnosed with a combined form of chronic peripheral edema comprised of true lymphedema, which was confirmed by lymphoscintigraphy, and filtration edema due to muscular inactivity. Edema as a side effect of tocilizumab was also suspected.
30408585 Arthritis in primary Sjögren's syndrome: Characteristics, outcome and treatment from Fren 2019 Jan OBJECTIVE: To describe the characteristics and the outcome of primary Sjögren Syndrome (pSS) associated arthritis and to compare the efficacy of different therapeutic regimen. METHODS: We conducted a retrospective study using Club Rhumatisme and Inflammation (CRI) and French Internal Medicine Society (SNFMI) networks. All patients with a diagnosis of pSS and at least one episode of clinical and/or echographic synovitis were included. Patients with synovitis (cases) were compared to pSS patients without synovitis (controls). RESULTS: 57 patients (93% women) were included with a median age of 54 years [45-63]. Patients with synovitis had more frequently lymph node enlargement (12.3% vs. 1.8%, p = .007) and a higher ESSDAI score (8 [6-12] vs. 2 [1-4], p < .0001). There was no difference concerning CRP levels, rheumatoid factor and cyclic citrullinated peptide (CCP)-antibodies positivity. Among 57 patients with synovitis, 101 various treatment courses have been used during the follow-up of 40 [22.5-77] months. First treatment course consisted in steroids alone (3.5%), steroids in association (79%) with hydroxychloroquine (HCQ) (49%), methotrexate (MTX) (35%), rituximab (RTX) (5.3%) or other immunosuppressive drugs (7%). HCQ, MTX, and RTX were associated with a significant reduction of tender and swollen joint count, and a significant steroids-sparing effect. No difference could be shown for the joint response between these treatment regimens. CONCLUSION: pSS articular manifestations may include synovitis which could mimic rheumatoid arthritis but differ by the absence of structural damage. Even if the use of HCQ, MTX, and RTX seem to be effective for joint involvement, the best regimen remains to be determined.
30418118 Aromatic hydrocarbon receptor provides a link between smoking and rheumatoid arthritis in 2019 May OBJECTIVES: Epidemiology shows that smoking plays a central role in rheumatoid arthritis (RA). The aim of this study was to evaluate the potential relationship between smoking, aromatic hydrocarbon receptor (AHR) and RA susceptibility. METHODS: We performed a hospital-based, case-control study of patients with RA and healthy controls. Expressions of AHR, cytochrome P4501A1(CYP1A1), aromatic hydrocarbon receptor repressor (AHRR) genes were assessed in peripheral blood mononuclear cells (PBMCs) and cultured cells using real-time PCR. The response of PBMCs to the AHR agonist, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and cigarette smoke extract (CSE) were cultured in vitro. RESULTS: AHR and its downstream gene expressions were demonstrated in smoking rheumatoid PBMCs and non-smoking patients with significantly higher expression in smoking patients. The observation was consistent with the sensitivity of RA PBMCs to TCDD and CSE stimulation demonstrated in vitro. CONCLUSIONS: Our study shows that smoking may be involved in the pathogenesis of RA by the AHR pathway.