Long-Term Risk of VTE in Sarcoidosis: A Nationwide Cohort Study

BACKGROUND

Chronic inflammation is increasingly recognized as a risk factor for VTE, but unlike other inflammatory diseases including systemic lupus erythematosus and rheumatoid arthritis, data on the risk of VTE in patients with sarcoidosis are sparse.

RESEARCH QUESTION

Do patients with sarcoidosis have a higher long-term risk of VTE (pulmonary embolism or DVT, and each of these individually) compared with the background population?

STUDY DESIGN AND METHODS

Using Danish nationwide registries, patients aged ≥ 18 years with newly diagnosed sarcoidosis (two or more inpatient/outpatient visits, 1996-2020) without prior VTE were matched 1:4 by age, sex, and comorbidities with individuals from the background population. The primary outcome was VTE.

RESULTS

We included 14,742 patients with sarcoidosis and 58,968 matched individuals (median age, 44.7 years; 57.2% male). The median follow-up was 8.8 years. Absolute 10-year risks of outcomes for patients with sarcoidosis vs the background population were the following: VTE, 2.9% vs 1.6% (P < .0001), pulmonary embolism, 1.5% vs 0.7% (P < .0001), and DVT, 1.6% vs 1.0% (P < .0001), respectively. In multivariable Cox regression, sarcoidosis was associated with an increased rate of all outcomes in the first year after diagnosis (VTE: hazard ratio [HR], 4.94; 95% CI, 3.61-6.75) and after the first year (VTE: HR, 1.65; 95% CI, 1.45-1.87) compared with the background population. These associations persisted when excluding patients with a history of cancer and censoring patients with incident cancer during follow-up. Three-month mortality was not significantly different between patients with VTE with and without sarcoidosis (adjusted HR, 0.84; 95% CI, 0.61-1.15).

INTERPRETATION

In this nationwide cohort study, sarcoidosis was associated with a higher long-term risk of VTE compared with a matched background population.

Treatment experiences with focus on IL-6R inhibition in patients with VEXAS-syndrome and a case of remission with azacytidine treatment

OBJECTIVES

The aim of the study was to evaluate the treatment response to Interleukin-6-receptor inhibitition (IL-6Ri), primarily tocilizumab, in patients with VEXAS.

METHODS

Data were obtained from review of hospital based clinical records and included symptoms, laboratory data, transfusion history, pathology reports, imaging, and treatment.

RESULTS

Fifteen patients were treated with tocilizumab intravenously. Two patients changed treatment to subcutaneous sarilumab. Three discontinued treatment due to treatment failure.Of the 10 patients with treatment-response and prednisone use prior to IL-6Ri one was tapered off prednisone, one used it intermittently, and seven patients could be reduced to 10 mg or less daily.Three patients exhibited a marked decrease in UBA1-levels during IL-6Ri which corresponded with symptom control and normalization of haemoglobin levels. However, in most a progressive marrow failure occurred as indicated by decreasing platelet levels, increasing MCV, and for some, declining haemoglobin levels and transfusion dependence in spite of control of the inflammatory symptoms and low c-reactive protein levels.One patient became refractory to both tocilizumab and sarilumab, and had previously failed conventional DMARDs, JAK-inhibition, TNFa-inhibition, and interleukin-1R-inhibiton. Treatment with 9 cycles of azacytidine resulted in complete symptom remission, discontinuation of prednisone, normalization of biochemical parameters and undetectable UBA1 mutation levels which has now lasted for 10 months since cessation of azacytidine.

CONCLUSION

IL-6Ri induces control of inflammatory symptoms and allows decreased prednisone usage in a large subset of VEXAS patients. However, most experience progressive bone marrow failure during IL-6Ri.Azacytidine could be a promising treatment strategy and warrants further investigation.

Influence of low socioeconomic status on mortality in granulomatosis with polyangiitis

Objectives: To evaluate the influence of low socioeconomic status (SES) on mortality among patients with granulomatosis with polyangiitis (GPA).Methods: Using nationwide registers, we established a cohort of 827 patients diagnosed with GPA in the public hospital system of Denmark. For each patient, information regarding educational level, civil status, employment status, and comorbidities at time of GPA diagnosis was collected. We used Cox regression analyses to calculate hazard ratios (HRs) adjusted for age, gender, calendar period of GPA diagnosis, and Charlson Comorbidity Index score for preceding illnesses as a measure of relative risk of death. We assessed the risk of death associated with three measures of low SES: basic schooling only, civil status as single, and being unemployed or recipient of disability pension.Results: The median age of patients at GPA diagnosis was 61 (interquartile range 51-69) years, and 508 were 18-64 years old. During a total of 4337 person-years, 237 patients died. Among patients aged 18-64 years at GPA diagnosis, all three measures of low SES were identified as risk factors for death [basic schooling only: HR = 2.04, 95% confidence interval (CI) 1.30-3.19; civil status as single: HR = 1.95, 95% CI 1.24-3.05; being unemployed or recipient of disability pension: HR = 2.96, 95% CI 1.72-5.08]. The association between low SES and mortality was less pronounced among patients aged ≥ 65 years.Conclusions: Our observations indicate that low SES is associated with increased mortality in GPA, especially among patients of working age.

Predictive value of a multi-biomarker disease activity score for clinical remission and radiographic progression in patients with early rheumatoid arthritis: a post-hoc study of the OPERA trial

OBJECTIVES

Measurement of serum biomarkers at disease onset may improve prediction of disease course in patients with early rheumatoid arthritis (RA). We evaluated the multi-biomarker disease activity (MBDA) score and early changes in MBDA score for prediction of 28-joint Disease Activity Score based on C-reactive protein (DAS28-CRP) remission and radiographic progression in the double-blinded OPERA trial.

METHOD

Treatment-naïve RA patients (N = 180) with moderate or high DAS28 were randomized to methotrexate (MTX) + adalimumab (n = 89) or MTX + placebo (n = 91) in combination with glucocorticoid injection into swollen joints. X-rays of hands and feet were evaluated at months 0 and 12 (n = 164) by the total Sharp van der Heijde score (TSS). The smallest detectable change (1.8 TSS units) defined radiographic progression (∆TSS ≥ 2). Clinical remission (DAS28-CRP < 2.6) was assessed at baseline and 6 months. MBDA score was determined at 0 and 3 months and tested in a multivariable logistic regression model for predicting DAS28 remission at 6 months and radiographic progression at 1 year.

RESULTS

Baseline MBDA score was independently associated with radiographic progression at 1 year [odds ratio (OR) = 1.03/unit, 95% confidence interval (CI) = 1.01-1.06], and changes in MBDA score from baseline to 3 months with clinical remission at 6 months [OR = 0.98/unit, 95% CI 0.96-1.00). In anti-cyclic citrullinated peptide antibody (anti-CCP)-positive patients, 35 of 89 with high MBDA score (> 44) showed radiographic progression (PPV = 39%), compared with 0 of 15 patients (NPV = 100%) with low/moderate MBDA score (≤ 44) (p = 0.003).

CONCLUSION

Early changes in MBDA score were associated with clinical remission based on DAS28-CRP at 6 months. In anti-CCP-positive patients, a non-high baseline MBDA score (≤ 44) had a clinical value by predicting very low risk of radiographic progression at 12 months.

Plasma MicroRNA Profiles in Patients with Early Rheumatoid Arthritis Responding to Adalimumab plus Methotrexate vs Methotrexate Alone: A Placebo-controlled Clinical Trial

OBJECTIVE

The aim was to identify plasma (i.e., cell-free) microRNA (miRNA) predicting antitumor necrosis and/or methotrexate (MTX) treatment response in patients enrolled in an investigator-initiated, prospective, double-blinded, placebo-controlled trial (The OPERA study, NCT00660647).

METHODS

We included 180 disease-modifying antirheumatic drug-naive patients with early rheumatoid arthritis (RA) randomized to adalimumab (ADA; n = 89) or placebo (n = 91) in combination with MTX. Plasma samples before and 3 months after treatment initiation were analyzed for 91 specific miRNA by quantitative reverse transcriptase-polymerase chain reaction on microfluidic dynamic arrays. A linear mixed-effects model was used to test for associations between pretreatment miRNA and changes in miRNA expression and American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) Boolean (28 joints) remission at 3 and 12 months, applying false discovery rate correction for multiple testing. Using leave-one-out cross validation, we built predictive multivariate miRNA models and estimated classification performances using receiver-operating characteristics (ROC) curves.

RESULTS

In the ADA group, a higher pretreatment level of miR-27a-3p was significantly associated with remission at 12 months. The level decreased in remitting patients between pretreatment and 3 months, and increased in nonremitting patients. No associations were found in the placebo group receiving only MTX. Two multivariate miRNA models were able to predict response to ADA treatment after 3 and 12 months, with 63% and 82% area under the ROC curves, respectively.

CONCLUSION

We identified miR-27a-3p as a potential predictive biomarker of ACR/EULAR remission in patients with early RA treated with ADA in combination with MTX. We conclude that pretreatment plasma-miRNA profiles may be of predictive value, but the results need confirmation in independent cohorts.

Monitoring total-body inflammation and damage in joints and entheses: the first follow-up study of whole-body magnetic resonance imaging in rheumatoid arthritis

OBJECTIVE

To investigate changes in whole-body magnetic resonance imaging (WBMRI) inflammatory and structural lesions in most joints and entheses in patients with rheumatoid arthritis (RA) treated with adalimumab.

METHODS

WBMRI was obtained at weeks 0, 6, 16, and 52 in a 52 week follow-up study of 37 RA patients starting treatment with adalimumab. Readability and reliability of WBMRI were investigated for 76 peripheral joints, 23 discovertebral units, the sacroiliac joints, and 33 entheses. Changes in WBMRI joint and entheses counts were investigated.

RESULTS

The readability of peripheral and axial joints was 82-100%, being less for elbows and small joints of the feet. For entheses, 72-100% were readable, except for entheses at the anterior chest wall, elbow, knee, and plantar fascia. The intrareader agreement was high for bone marrow oedema (BMO), bone erosion (80-100%), and enthesitis (77-100%), and slightly lower for synovitis and soft tissue inflammation (50-100%). All synovitis, BMO, and soft tissue inflammation counts decreased numerically during treatment. The 26-joint synovitis WBMRI count decreased significantly during the first 16 weeks for patients with a good European League Against Rheumatism (EULAR) response (from median 6 to 4, p < 0.05), but not for patients with a moderate or no EULAR response. There were no overall changes in structural lesions.

CONCLUSIONS

WBMRI allows simultaneous monitoring of most axial and peripheral joints and entheses in RA patients and can visualize a decrease in inflammatory counts during treatment. This first WBMRI follow-up study of patients with RA encourages further investigation of the usefulness of WBMRI in RA.

Hand bone loss in early rheumatoid arthritis during a methotrexate-based treat-to-target strategy with or without adalimumab-a substudy of the optimized treatment algorithm in early RA (OPERA) trial

This study aims to investigate 1-year hand bone loss (HBL_1-year) in early rheumatoid arthritis (RA) patients treated with a methotrexate (MTX) and intra-articular triamcinolone treat-to-target strategy +/- adalimumab and to determine if HBL_6months is associated with radiographic progression after 2 years. In a clinical trial (OPERA) of 180 treatment-naive early RA patients, bone mineral density (BMD) was estimated from hand radiographs with digital X-ray radiogrammetry (DXR) at baseline, after 6 (n = 90) and 12 months (n = 70) of follow-up. Baseline and 2-year radiographs were scored according to the Sharp/van der Heijde method. Baseline characteristics and HBL_6months (0-6 months changes in DXR-BMD) were investigated as predictors of structural damage by univariate linear (∆ total Sharp/van der Heijde score (TSS) as dependent variable) and logistic (+/-radiographic progression (∆TSS >0) as dependent variable) regression analyses. Variables with p < 0.10 were included in multivariable models. In 70 patients with available HBL_1-year data, HBL_1-year was median (interquartile range (IQR)) -1.9 (-3.3; -0.26 mg/cm²) in the MTX + placebo group and -1.8 (-3.6; 0.06) mg/cm² in the MTX + adalimumab group, p = 0.98, Wilcoxon signed-rank. Increased HBL (compared to general population reference values) was found in 26/37 and 23/33 patients in the MTX + placebo and MTX + adalimumab groups, chi-squared = 0.99. In 90 patients with HBL_6months data and 2-year radiographic data, HBL_6months was independently associated with ∆TSS after 2 years (β = -0.086 (95% confidence interval = -0.15; -0.025) TSS unit/mg/cm² increase, p = 0.006) but not with presence of radiographic progression (∆TSS >0) (OR 0.96 (0.92-1.0), p = 0.10). In early RA patients treated with a methotrexate-based treat-to-target strategy, the majority of patients had increased HBL_1-year, irrespective of adalimumab; HBL_6months was independently associated with ∆TSS after 2 years.

Clinical and radiographic outcome of a treat-to-target strategy using methotrexate and intra-articular glucocorticoids with or without adalimumab induction: a 2-year investigator-initiated, double-blinded, randomised, controlled trial (OPERA)

OBJECTIVES

To study clinical and radiographic outcomes after withdrawing 1 year's adalimumab induction therapy for early rheumatoid arthritis (eRA) added to a methotrexate and intra-articular triamcinolone hexacetonide treat-to-target strategy (NCT00660647).

METHODS

Disease-modifying antirheumatic drug (DMARD)-naive patients with eRA started methotrexate (20 mg/week) and intra-articular triamcinolone (20 mg/ml) for 2 years. In addition, they were randomised to receive placebo adalimumab (DMARD group, n=91) or adalimumab (40 mg/every other week) (DMARD+adalimumab group, n=89) during the first year. Sulfasalazine and hydroxychloroquine were added if disease activity persisted after 3 months. During year 2, synthetic DMARDs continued. Adalimumab was (re)initiated if active disease reoccurred. Clinical response, remission, disability, quality of life and radiographic changes were assessed.

RESULTS

One year after adalimumab withdrawal, treatment profiles and clinical responses did not differ between groups. In the DMARD/DMARD+adalimumab groups, the median 2-year methotrexate dose was 20/20 mg/week (p=0.45), triple DMARD therapy had been initiated in 33/27 patients (p=0.49), adalimumab was (re)initiated in 12/12 patients and cumulative triamcinolone dose was 160/120 mg (p=0.15). The treatment target (disease activity score, 4 variables, C-reactive protein (DAS28CRP) ≤3.2 or DAS28>3.2 without swollen joints) was achieved at all visits in ≥85% of patients in year 2; remission rates were DAS28CRP<2.6:69%/66%; Clinical Disease Activity Index ≤2.8:55%/57%; Simplified Disease Activity Index <3.3:54%/49%; American College of Rheumatology/European League against Rheumatism (28 joints):44%/45% (p=0.66-1.00). Radiographic progression (Δtotal Sharp score/year) was similar 1.31/0.53 (p=0.12). Erosive progression (Δerosion score (ES)/year) was year 1:0.57/0.06 (p=0.02); year 2:0.38/0.05 (p=0.005). Proportion of patients without erosive progression (ΔES≤0) was year 1: 59%/76% (p=0.03); year 2:64%/79% (p=0.04).

CONCLUSIONS

An aggressive triamcinolone and synthetic DMARD treat-to-target strategy in eRA provided excellent 2-year clinical and radiographic disease control independent of adalimumab induction therapy. ES progression was slightly less during and following adalimumab induction therapy.

TRIAL REGISTRATION NUMBER

NCT00660647.

A treat-to-target strategy with methotrexate and intra-articular triamcinolone with or without adalimumab effectively reduces MRI synovitis, osteitis and tenosynovitis and halts structural damage progression in early rheumatoid arthritis: results from the OPERA randomised controlled trial

OBJECTIVES

To investigate whether a treat-to-target strategy with methotrexate and intra-articular glucocorticosteroid injections suppresses MRI inflammation and halts structural damage progression in patients with early rheumatoid arthritis (ERA), and whether adalimumab provides an additional effect.

METHODS

In a double-blind, placebo-controlled trial, 85 disease-modifying antirheumatic drug-naïve patients with ERA were randomised to receive methotrexate, intra-articular glucocorticosteroid injections and placebo/adalimumab (43/42). Contrast-enhanced MRI of the right hand was performed at months 0, 6 and 12. Synovitis, osteitis, tenosynovitis, MRI bone erosion and joint space narrowing (JSN) were scored with validated methods. Dynamic contrast-enhanced MRI (DCE-MRI) was carried out in 14 patients.

RESULTS

Synovitis, osteitis and tenosynovitis scores decreased highly significantly (p<0.0001) during the 12-months' follow-up, with mean change scores of -3.7 (median -3.0), -2.2 (-1) and -5.3 (-4.0), respectively. No overall change in MRI bone erosion and JSN scores was seen, with change scores of 0.1 (0) and 0.2 (0). The tenosynovitis score at month 6 was significantly lower in the adalimumab group, 1.3 (0), than in the placebo group, 3.9 (2), Mann-Whitney: p<0.035. Furthermore, the osteitis score decreased significantly during the 12-months' follow-up in the adalimumab group, but not in the placebo group, Wilcoxon: p=0.001-0.002 and p=0.062-0.146. DCE-MRI parameters correlated closely with conventional MRI inflammatory parameters. Clinical measures decreased highly significantly during follow-up.

CONCLUSIONS

A treat-to-target strategy with methotrexate and intra-articular glucocorticosteroid in patients with ERA effectively decreased synovitis, osteitis and tenosynovitis and halted structural damage progression as judged by MRI. The findings suggest that addition of adalimumab is associated with further suppression of osteitis and tenosynovitis.

Identification of the tyrosine-protein phosphatase non-receptor type 2 as a rheumatoid arthritis susceptibility locus in europeans

OBJECTIVES

Genome-wide association studies have facilitated the identification of over 30 susceptibility loci for rheumatoid arthritis (RA). However, evidence for a number of potential susceptibility genes have not so far reached genome-wide significance in studies of Caucasian RA.

METHODS

A cohort of 4286 RA patients from across Europe and 5642 population matched controls were genotyped for 25 SNPs, then combined in a meta-analysis with previously published data.

RESULTS

Significant evidence of association was detected for nine SNPs within the European samples. When meta-analysed with previously published data, 21 SNPs were associated with RA susceptibility. Although SNPs in the PTPN2 gene were previously reported to be associated with RA in both Japanese and European populations, we show genome-wide evidence for a different SNP within this gene associated with RA susceptibility in an independent European population (rs7234029, P = 4.4×10(-9)).

CONCLUSIONS

This study provides further genome-wide evidence for the association of the PTPN2 locus (encoding the T cell protein tyrosine phosphastase) with Caucasian RA susceptibility. This finding adds to the growing evidence for PTPN2 being a pan-autoimmune susceptibility gene.

The frequency of anti-infliximab antibodies in patients with rheumatoid arthritis treated in routine care and the associations with adverse drug reactions and treatment failure

OBJECTIVES

To investigate the frequency of anti-infliximab antibodies in patients with RA and the associations with adverse drug reactions and treatment failure.

METHODS

Based on the DANBIO registry, patients with RA who initiated treatment with infliximab at Hvidovre Hospital between 2000 and 2008 and had available serum samples were identified. The patients were followed for 52 weeks. Anti-infliximab antibodies were determined prior to infusion at baseline and during follow-up (weeks 2, 6, 14 and 52 or at withdrawal) using the IMPACT indirect assay (Roche Diagnostics) and merged with clinical data prospectively registered in the DANBIO registry.

RESULTS

A total of 218 patients with RA were included (80% females, median age 56 years, disease duration 10 years, 65% RF positive, median DAS28 = 5.0). During the 52-week follow-up, 28 patients (13%) withdrew due to adverse events and 50 (23%) due to treatment failure. Antibodies were detected in 118 patients (54%) during follow-up. Patients with detectable anti-infliximab antibodies after 6 weeks had an increased risk of adverse drug reactions [hazard ratio (HR) = 5.06, 95% CI 2.36, 10.84; P < 0.0001] compared with patients without anti-infliximab antibodies. Similar results were observed in patients with anti-infliximab antibodies after 14 weeks (HR = 3.30, 95% CI 1.56, 6.99; P = 0.0009). Patients with detectable anti-infliximab antibodies during the 52-week follow-up were less likely to achieve sustained minimal disease activity and remission.

CONCLUSION

Early anti-infliximab antibody formation increased the risk of adverse drug reactions, including infusion reactions. Anti-infliximab antibody formation during the 52-week follow-up decreased the likelihood of minimal disease activity and remission in patients with RA treated in routine care.

Adalimumab added to a treat-to-target strategy with methotrexate and intra-articular triamcinolone in early rheumatoid arthritis increased remission rates, function and quality of life. The OPERA Study: an investigator-initiated, randomised, double-blind, parallel-group, placebo-controlled trial

OBJECTIVES

An investigator-initiated, double-blinded, placebo-controlled, treat-to-target protocol (Clinical Trials:NCT00660647) studied whether adalimumab added to methotrexate and intra-articular triamcinolone as first-line treatment in early rheumatoid arthritis (ERA) increased the frequency of low disease activity (DAS28CRP<3.2) at 12 months.

METHODS

In 14 Danish hospital-based clinics, 180 disease-modifying anti-rheumatic drugs (DMARD)-naïve ERA patients (<6 months duration) received methotrexate 7.5 mg/week (increased to 20 mg/week within 2 months) plus adalimumab 40 mg every other week (adalimumab-group, n=89) or methotrexate+placebo-adalimumab (placebo-group, n=91). At all visits, triamcinolone was injected into swollen joints (max. four joints/visit). If low disease activity was not achieved, sulfasalazine 2 g/day and hydroxychloroquine 200 mg/day were added after 3 months, and open-label biologics after 6-9 months. Efficacy was assessed primarily on the proportion of patients who reached treatment target (DAS28CRP<3.2). Secondary endpoints included DAS28CRP, remission, Health Assessment Questionnaire (HAQ), EQ-5D and SF-12. Analysis was by intention-to-treat with last observation carried forward.

RESULTS

Baseline characteristics were similar between groups. In the adalimumab group/placebo group the 12-month cumulative triamcinolone doses were 5.4/7.0 ml (p=0.08). Triple therapy was applied in 18/27 patients (p=0.17). At 12 months, DAS28CRP<3.2 was reached in 80%/76% (p=0.65) and DAS28CRP was 2.0 (1.7-5.2) (medians (5th/95th percentile ranges)), versus 2.6 (1.7-4.7) (p=0.009). Remission rates were: DAS28CRP<2.6: 74%/49%, Clinical Disease Activity Index≤2.8: 61%/41%, Simplified Disease Activity Index<3.3: 57%/37%, European League Against Rheumatism/American College of Rheumatology Boolean: 48%/30% (0.0008<p<0.014, number-needed-to-treat: 4.0-5.4). Twelve months HAQ, SF12PCS and EQ-5D improvements were most pronounced in the adalimumab group. Treatments were well tolerated.

CONCLUSIONS

Adalimumab added to methotrexate and intra-articular triamcinolone as first-line treatment did not increase the proportion of patients who reached the DAS28CRP<3.2 treatment target, but improved DAS28CRP, remission rates, function and quality of life in DMARD-naïve ERA.

CD6 and syntaxin binding protein 6 variants and response to tumor necrosis factor alpha inhibitors in Danish patients with rheumatoid arthritis

BACKGROUND

TNFα inhibitor therapy has greatly improved the treatment of patients with rheumatoid arthritis, however at least 30% do not respond. We aimed to investigate insertions and deletions (INDELS) associated with response to TNFα inhibitors in patients with rheumatoid arthritis (RA).

METHODOLOGY AND PRINCIPAL FINDINGS

In the DANBIO Registry we identified 237 TNFα inhibitor naïve patients with RA (81% women; median age 56 years; disease duration 6 years) who initiated treatment with infliximab (n=160), adalimumab (n=56) or etanercept (n=21) between 1999 and 2008 according to national treatment guidelines. Clinical response was assessed at week 26 using EULAR response criteria. Based on literature, we selected 213 INDELS potentially related to RA and treatment response using the GeneVa® (Compugen) in silico database of 350,000 genetic variations in the human genome. Genomic segments were amplified by polymerase chain reaction (PCR), and genotyped by Sanger sequencing or fragment analysis. We tested the association between genotypes and EULAR good response versus no response, and EULAR good response versus moderate/no response using Fisher's exact test. At baseline the median DAS28 was 5.1. At week 26, 68 (29%) patients were EULAR good responders, while 81 (34%) and 88 (37%) patients were moderate and non-responders, respectively. A 19 base pair insertion within the CD6 gene was associated with EULAR good response vs. no response (OR=4.43, 95% CI: 1.99-10.09, p=7.211×10(-5)) and with EULAR good response vs. moderate/no response (OR=4.54, 95% CI: 2.29-8.99, p=3.336×10(-6)). A microsatellite within the syntaxin binding protein 6 (STXBP6) was associated with EULAR good response vs. no response (OR=4.01, 95% CI: 1.92-8.49, p=5.067×10(-5)).

CONCLUSION

Genetic variations within CD6 and STXBP6 may influence response to TNFα inhibitors in patients with RA.

Promoter polymorphisms in the chitinase 3-like 1 gene influence the serum concentration of YKL-40 in Danish patients with rheumatoid arthritis and in healthy subjects

Introduction

The present study investigates the association between single nucleotide polymorphisms (SNPs) in the chitinase 3-like 1 (CHI3L1) gene and serum concentrations of YKL-40 in Danish patients with rheumatoid arthritis (RA) and healthy controls as well as the association with RA in the Danish population. The CHI3L1 gene is located on chromosome 1q32.1 and encodes the YKL-40 glycoprotein. YKL-40 concentrations are elevated in the serum of patients with RA compared to healthy subjects, and YKL-40 has been suggested to be an auto-antigen and may play a role in development of RA and in inflammation.

Methods

Eight SNPs in the CHI3L1 gene and promotor were genotyped in 308 patients with RA and 605 controls (healthy blood donors) using TaqMan allele discrimination assays. Serum concentrations of YKL-40 were determined by an enzyme-linked immunosorbent assay (ELISA).

Results

We found significant association between the serum concentrations of YKL-40 and polymorphism in the CHI3L1 gene among both patients with RA and controls. The g.-131(C > G) polymorphism (rs4950928) was most strongly associated with age adjusted serum concentrations of YKL-40 in patients with RA (P < 2.4e-8) and controls (P < 2.2e-16). No significant allelic- or genotypic association with RA was found in this Danish cohort.

Conclusions

We suggest that the g.-131(C > G) promoter polymorphism has a substantial impact on serum concentrations of YKL-40 in patients with RA and healthy subjects. However, the polymorphism does not seem to confer risk to RA itself. The effect of CHI3L1 polymorphism on clinical outcome or the response to treatment in patients with RA remains to be investigated.