Is glucocorticoid bridging therapy associated with later use of glucocorticoids and biological DMARDs during the disease course of patients with rheumatoid arthritis in daily practice? A real-world data analysis

OBJECTIVE

To evaluate if initially starting glucocorticoid (GC) bridging leads to a higher probability of long-term GC and biological (b)DMARD use in rheumatoid arthritis (RA)-patients.

METHODS

Electronical health records data from newly diagnosed RA-patients from the Leiden University Medical Center were used. Patients who started GC as part of initial treatment (iGC group) and who did not (niGC group) were compared in terms of GC and bDMARD use later in the disease course. Multivariable adjustment was performed to account for confounding by indication.

RESULTS

465/932 newly diagnosed RA-patients (50 %) were treated with GC as initial treatment step. Patients in the iGC group were older, included fewer females, had a higher disease activity at baseline compared to the niGC group plus a more rapid decrease in DAS28 in the first 6 months. During follow-up, 42 % of the iGC group started a second course of GC and 17 % started a bDMARD, compared to 34 % and 13 % In the niGC group. The hazard to start a bDMARD later in the disease course was not significantly different between the two groups in two time periods (0.34 95 %CI(0.09;1.21) resp. 1.48 95 %CI (0.98;2.22)), but the hazard to (re)start GC later on was higher for the iGC group (aHR 1.37 95 %CI(1.09;1.73)).

CONCLUSION

In this daily practice cohort of newly diagnosed RA patients, patients in the iGC group had a more rapid DAS28 decrease and an increased probability of starting GC later on compared to the niGC group. The probability of bDMARD use was not significantly increased.

Administration of an adeno-associated viral vector expressing interferon-β in patients with inflammatory hand arthritis, results of a phase I/II study

OBJECTIVE

Inflammatory hand arthritis (IHA) results in impaired function. Local gene therapy with ART-I02, a recombinant adeno-associated virus (AAV) serotype 5 vector expressing interferon (IFN)-β, under the transcriptional control of nuclear factor κ-B responsive promoter, was preclinically shown to have favorable effects. This study aimed to investigate the safety and tolerability of local gene therapy with ART-I02 in patients with IHA.

METHODS

In this first-in-human, dose-escalating, cohort study, 12 IHA patients were to receive a single intra-articular (IA) injection of ART-I02 ranging 0.3 × 10¹²-1.2 × 10¹³ genome copies in an affected hand joint. Adverse events (AEs), routine safety laboratory and the clinical course of disease were periodically evaluated. Baseline- and follow-up contrast enhanced magnetic resonance images (MRIs), shedding of viral vectors in bodily fluids, and AAV5 and IFN-β immune responses were evaluated. A data review committee provided safety recommendations.

RESULTS

Four patients were enrolled. Long-lasting local AEs were observed in 3 patients upon IA injection of ART-I02. The AEs were moderate in severity and could be treated conservative. Given the duration of the AEs and their possible or probable relation to ART-I02, no additional patients were enrolled. No systemic treatment emergent AEs were observed. The MRIs reflected the AEs by (peri)arthritis. No T-cell response against AAV5 or IFN-β, nor IFN-β antibodies could be detected. Neutralizing antibody titers against AAV5 raised post-dose.

CONCLUSION

Single IA doses of 0.6 × 10¹² or 1.2 × 10¹² ART-I02 vector genomes were administered without systemic side effects or serious AEs. However, local tolerability was insufficient for continuation.

TRIAL REGISTRATION

NCT02727764.

Evolution of anti-modified protein antibody responses can be driven by consecutive exposure to different post-translational modifications

Background

Besides anti-citrullinated protein antibodies (ACPA), rheumatoid arthritis patients (RA) often display autoantibody reactivities against other post-translationally modified (PTM) proteins, more specifically carbamylated and acetylated proteins. Immunizing mice with one particular PTM results in an anti-modified protein antibody (AMPA) response recognizing different PTM-antigens. Furthermore, human AMPA, isolated based on their reactivity to one PTM, cross-react with other PTMs. However, it is unclear whether the AMPA-reactivity profile is “fixed” in time or whether consecutive exposure to different PTMs can shape the evolving AMPA response towards a particular PTM.

Methods

Longitudinally collected serum samples of 8 human individuals at risk of RA and 5 with early RA were tested with ELISA, and titers were analyzed to investigate the evolution of the AMPA responses over time. Mice (13 per immunization group in total) were immunized with acetylated (or carbamylated) protein (ovalbumin) twice or cross-immunized with an acetylated and then a carbamylated protein (or vice versa) and their serum was analyzed for AMPA responses.

Results

Human data illustrated dynamic changes in AMPA-reactivity profiles in both individuals at risk of RA and in early RA patients. Mice immunized with either solely acetylated or carbamylated ovalbumin (AcOVA or CaOVA) developed reactivity against both acetylated and carbamylated antigens. Irrespective of the PTM-antigen used for the first immunization, a booster immunization with an antigen bearing the other PTM resulted in increased titers to the second/booster PTM. Furthermore, cross-immunization skewed the overall AMPA-response profile towards a relatively higher reactivity against the “booster” PTM.

Conclusions

The relationship between different reactivities within the AMPA response is dynamic. The initial exposure to a PTM-antigen induces cross-reactive responses that can be boosted by an antigen bearing this or other PTMs, indicating the formation of cross-reactive immunological memory. Upon subsequent exposure to an antigen bearing another type of PTM, the overall reactivity pattern can be skewed towards better recognition of the later encountered PTM. These data might explain temporal differences in the AMPA-response profile and point to the possibility that the PTM responsible for the initiation of the AMPA response may differ from the PTM predominantly recognized later in time.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02687-5.

Handwork vs machine: a comparison of rheumatoid arthritis patient populations as identified from EHR free-text by diagnosis extraction through machine-learning or traditional criteria-based chart review

Background

Electronic health records (EHRs) offer a wealth of observational data. Machine-learning (ML) methods are efficient at data extraction, capable of processing the information-rich free-text physician notes in EHRs. The clinical diagnosis contained therein represents physician expert opinion and is more consistently recorded than classification criteria components.

Objectives

To investigate the overlap and differences between rheumatoid arthritis patients as identified either from EHR free-text through the extraction of the rheumatologist diagnosis using machine-learning (ML) or through manual chart-review applying the 1987 and 2010 RA classification criteria.

Methods

Since EHR initiation, 17,662 patients have visited the Leiden rheumatology outpatient clinic. For ML, we used a support vector machine (SVM) model to identify those who were diagnosed with RA by their rheumatologist. We trained and validated the model on a random selection of 2000 patients, balancing PPV and sensitivity to define a cutoff, and assessed performance on a separate 1000 patients. We then deployed the model on our entire patient selection (including the 3000). Of those, 1127 patients had both a 1987 and 2010 EULAR/ACR criteria status at 1 year after inclusion into the local prospective arthritis cohort. In these 1127 patients, we compared the patient characteristics of RA cases identified with ML and those fulfilling the classification criteria.

Results

The ML model performed very well in the independent test set (sensitivity=0.85, specificity=0.99, PPV=0.86, NPV=0.99). In our selection of patients with both EHR and classification information, 373 were recognized as RA by ML and 357 and 426 fulfilled the 1987 or 2010 criteria, respectively. Eighty percent of the ML-identified cases fulfilled at least one of the criteria sets.

Both demographic and clinical parameters did not differ between the ML extracted cases and those identified with EULAR/ACR classification criteria.

Conclusions

With ML methods, we enable fast patient extraction from the huge EHR resource. Our ML algorithm accurately identifies patients diagnosed with RA by their rheumatologist. This resulting group of RA patients had a strong overlap with patients identified using the 1987 or 2010 classification criteria and the baseline (disease) characteristics were comparable. ML-assisted case labeling enables high-throughput creation of inclusive patient selections for research purposes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02553-4.

Complex medical history of a patient with a compound heterozygous mutation in C1QC

Introduction

C1q is an essential part of the classical pathway of complement activation. Genetic deficiencies, caused by homozygous mutations in one of the C1q genes, are rare and are strongly associated with development of systemic lupus erythematosus (SLE). Here we describe a C1q-deficient patient with a compound heterozygous mutation.

Material and methods

Serum was analysed with enzyme-linked immunosorbent assay (ELISA) and Western blot for the presence of C1q, and DNA and RNA sequencing was performed to identify the mutations and confirm that these were located on different chromosomes.

Results

The medical history of the patient includes SLE diagnosis at age 11 years with cerebral involvement at age 13, various infections, osteonecrosis and hemophagocytic syndrome. Using ELISA and Western blot, we confirmed the absence of C1q in the serum of the patient. Using DNA sequencing, two mutations in the C1QC gene were identified: c.100G > A p.(Gly34Arg) and c.205C > T p.(Arg69X). With RNA sequencing we confirmed that the mutations are located on different chromosomes.

Discussion

The patient described in this case report has a compound heterozygous mutation in C1QC resulting in C1q deficiency.

Does treatment strategy influence the ability to achieve and sustain DMARD-free remission in patients with RA? Results of an observational study comparing an intensified DAS-steered treatment strategy with treat to target in routine care

OBJECTIVES

To study the impact of treatment strategy on achieving and sustaining disease-modifying antirheumatic drug (DMARD)-free remission in patients with rheumatoid arthritis (RA).

METHODS

Two hundred seventy-nine RA patients (median follow-up 7.8 years) were studied. Of these, 155 patients participated in a disease activity score (DAS) < 1.6 steered trial aimed at DMARD-free remission. Initial treatment comprised methotrexate with high-dose prednisone (60 mg/day) and a possibility to start biologicals after 4 months. In the same period and hospital, 124 patients were treated according to routine care, comprising DAS < 2.4 steered treatment. Percentages of DMARD-free remission (absence of synovitis for ≥ 1 year after DMARD cessation), late flares (recurrence of clinical synovitis ≥ 1 year after DMARD cessation), and DMARD-free sustained remission (DMARD-free remission sustained during complete follow-up) were compared between both treatment strategies.

RESULTS

Patients receiving intensive treatment were younger and more often ACPA-positive. On a group level, there was no significant association between intensive treatment and DMARD-free remission (35% vs 29%, corrected hazard ratio (HR) 1.4, 95%CI 0.9-2.2), nor in ACPA-negative RA (49% versus 44%). In ACPA-positive RA intensive treatment resulted in more DMARD-free remission (25% vs 6%, corrected HR 4.9, 95%CI 1.4-17). Intensive treatment was associated with more late flares (20% versus 8%, HR 2.3, 95%CI 0.6-8.3). Subsequently, there was no difference in DMARD-free sustained remission on a group level (28% versus 27%), nor in the ACPA-negative (43% versus 42%) or ACPA-positive stratum (17% versus 6%, corrected HR 3.1, 95%CI 0.9-11).

CONCLUSIONS

Intensive treatment did not result in more DMARD-free sustained remission, compared to routine up-to-date care. The data showed a tendency towards an effect of intensive treatment in ACPA-positive RA; this needs further investigation.

Outcomes of neuropsychiatric events in systemic lupus erythematosus based on clinical phenotypes; prospective data from the Leiden NP SLE cohort

Objective

The objective of this study was to assess whether clinical and patient’s reported outcomes are associated with a different pathophysiological origin of neuropsychiatric events presenting in systemic lupus erythematosus.

Methods

A total of 232 neuropsychiatric events presenting in 131 systemic lupus erythematosus patients were included. Neuropsychiatric systemic lupus erythematosus diagnosis was established per event by multidisciplinary evaluation. All neuropsychiatric events were divided according to a suspected underlying pathophysiological process into one of the following: non-neuropsychiatric systemic lupus erythematosus related, inflammatory and ischaemic neuropsychiatric systemic lupus erythematosus. The clinical outcome of all neuropsychiatric events was determined by a physician-completed four-point Likert scale. Health-related quality of life was measured with the subscales of the patient-generated Short Form 36 (SF-36) health survey questionnaire. The change between scores at paired visits of all domain scores, mental component summary (SF-36 MCS) and physical component summary (SF-36 PCS) scores were retrospectively calculated and used as patient-reported outcome. The association among these outcomes and the different origin of neuropsychiatric events was obtained using multiple logistic regression analysis.

Results

The clinical status of 26.8% non-neuropsychiatric systemic lupus erythematosus events, 15.8% ischaemic neuropsychiatric systemic lupus erythematosus and 51.6% inflammatory neuropsychiatric systemic lupus erythematosus improved after re-assessment. Almost all SF-36 domains had a positive change at re-assessment in all groups independently of the origin of neuropsychiatric events. Neuropsychiatric systemic lupus erythematosus ( B = 0.502; p < 0.001) and especially inflammatory neuropsychiatric systemic lupus erythematosus ( B = 0.827; p < 0.001) had better clinical outcome, with change in disease activity being the only important predictor. The change in SF-36 MCS was also independently associated with neuropsychiatric systemic lupus erythematosus ( B = 5.783; p < 0.05) and inflammatory neuropsychiatric systemic lupus erythematosus ( B = 11.133; p < 0.001). Disease duration and change in disease activity were the only predictors in both cases. The change in SF-36 PCS was only negatively associated with age.

Conclusion

Inflammatory neuropsychiatric systemic lupus erythematosus events have better clinical outcome and meaningful improvement in SF-36 MCS than ischaemic neuropsychiatric systemic lupus erythematosus or non-neuropsychiatric systemic lupus erythematosus.

Phase 1b randomized, double-blind study of namilumab, an anti-granulocyte macrophage colony-stimulating factor monoclonal antibody, in mild-to-moderate rheumatoid arthritis

Background

Namilumab (AMG203) is an immunoglobulin G1 monoclonal antibody that binds with high affinity to the GM-CSF ligand. This was a phase 1b, randomized, double-blind study (PRIORA) to assess namilumab in active, mild-to-moderate rheumatoid arthritis (RA). The primary outcome was the safety and tolerability of repeated subcutaneous injections of namilumab in patients with mild-to-moderate RA.

Methods

Adults with mild-to-moderate RA on stable methotrexate doses for ≥12 weeks were eligible. Patients received three subcutaneous injections of namilumab 150 or 300 mg, or placebo on days 1, 15, and 29, with 12 weeks’ follow-up. Primary objective was safety/tolerability.

Results

Patients in cohort 1 were randomized to namilumab 150 mg (n = 8) or placebo (n = 5). In cohort 2, patients were randomized to namilumab 300 mg (n = 7) or placebo (n = 4). Incidence of treatment-emergent adverse events (TEAEs) was similar across the three groups (namilumab 150 mg: 63%; namilumab 300 mg: 57%; placebo: 56%). TEAEs in ≥10% of patients were nasopharyngitis (17%) and exacerbation/worsening of RA (13%). No anti-namilumab antibodies were detected. The pharmacokinetics of namilumab were linear and typical of a monoclonal antibody with subcutaneous administration. In a post hoc efficacy, per protocol analysis (n = 21), patients randomized to namilumab showed greater improvement in Disease Activity Score 28 (erythrocyte sedimentation rate and C-reactive protein [CRP]), swelling joint counts and tender joint counts compared with placebo. Difference in mean DAS28-CRP changes from baseline between namilumab and placebo favored namilumab at both doses and at all time points. In addition area under the curve for DAS28-CRP was analyzed as time-adjusted mean change from baseline. A significant improvement in DAS28-CRP was shown with namilumab (150 and 300 mg groups combined) compared with placebo at day 43 (p = 0.0117) and also 8 weeks after last dosing at day 99 (p = 0.0154).

Conclusions

Subcutaneous namilumab was generally well tolerated. Although namilumab demonstrated preliminary evidence of efficacy, patient numbers were small; phase 2 studies are ongoing.

Trial registration

ClinicalTrials.gov, NCT01317797. Registered 18 February 2011.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1267-3) contains supplementary material, which is available to authorized users.

Neuropsychiatric symptoms in systemic lupus erythematosus: impact on quality of life

Objective

Assess quality of life in patients with systemic lupus erythematosus (SLE) presenting with neuropsychiatric symptoms (neuropsychiatric SLE, NPSLE).

Methods

Quality of life was assessed using the Short-Form 36 item Health Survey (SF-36) in patients visiting the Leiden NPSLE clinic at baseline and at follow-up. SF-36 subscales and summary scores were calculated and compared with quality of life of the general Dutch population and patients with other chronic diseases.

Results

At baseline, quality of life was assessed in 248 SLE patients, of whom 98 had NPSLE (39.7%). Follow-up data were available for 104 patients (42%), of whom 64 had NPSLE (61.5%). SLE patients presenting neuropsychiatric symptoms showed a significantly reduced quality of life in all subscales of the SF-36. Quality of life at follow-up showed a significant improvement in physical functioning role (p = 0.001), social functioning (p = 0.007), vitality (p = 0.023), mental health (p = 0.014) and mental component score (p = 0.042) in patients with neuropsychiatric symptoms not attributed to SLE, but no significant improvement was seen in patients with NPSLE.

Conclusion

Quality of life is significantly reduced in patients with SLE presenting neuropsychiatric symptoms compared with the general population and patients with other chronic diseases. Quality of life remains considerably impaired at follow-up. Our results illustrate the need for biopsychosocial care in patients with SLE and neuropsychiatric symptoms.

Presence of anticitrullinated protein antibodies in a large population-based cohort from the Netherlands

OBJECTIVES

To determine the prevalence of anticitrullinated protein antibodies (ACPAs) and their association with known rheumatoid arthritis (RA) risk factors in the general population.

METHODS

Lifelines is a multidisciplinary prospective population-based cohort study in the Netherlands. Cross-sectional data from 40 136 participants were used. The detection of ACPA was performed by measuring anti-CCP2 on the Phadia-250 analyser with levels ≥6.2 U/mL considered positive. An extensive questionnaire was taken on demographic and clinical information, including smoking, periodontal health and early symptoms of musculoskeletal disorders. RA was defined by a combination of self-reported RA, medication use for the indication of rheumatism and visiting a medical specialist within the last year.

RESULTS

Of the total 40 136 unselected individuals, 401 (1.0%) had ACPA level ≥6.2 U/mL. ACPA positivity was significantly associated with older age, female gender, smoking, joint complaints, RA and first degree relatives with rheumatism. Of the ACPA-positive participants, 22.4% had RA (15.2% had defined RA according to our criteria and 7.2% self-reported RA only). In participants without RA, 311 (0.8%) were ACPA-positive. In the non-RA group, older age, smoking and joint complaints remained significantly more frequently present in ACPA-positive compared with ACPA-negative participants.

CONCLUSIONS

In this large population-based study, the prevalence of ACPA levels ≥6.2 U/mL was 1.0% for the total group and 0.8% when excluding patients with RA. Older age, smoking and joint complaints were more frequently present in ACPA-positive Lifelines participants. To our knowledge, this study is the largest study to date on ACPA positivity in the general, mostly Caucasian population.

Age affects joint space narrowing in patients with early active rheumatoid arthritis

BACKGROUND

Joint space narrowing (JSN) in rheumatoid arthritis (RA) may be a manifestation of (primary) osteoarthritis becoming more prominent with age. We investigated the severity and predictors of JSN progression among different age groups.

METHODS

10-year follow-up data of the BeSt study, a randomised controlled treat-to-target trial in early RA were used. Annual X-rays of hands and feet were scored using the Sharp/van der Heijde score (SHS). Subgroups were defined by age at baseline: ≥55, ≥40<55 and <40 years. JSN progression predictors were assessed by Poisson regression.

RESULTS

Baseline JSN scores (median (IQR)) were higher in patients ≥55 (2.0 (0.0-6.0)) compared with the other age groups: 1.0 (0.0-3.0) ≥40<55 and 0.3 (0.0-3.0) <40, p<0.001. After 10 years, total JSN and SHS were similar in all age groups. In patients ≥55 the mean erythrocyte sedimentation rate (ESR) over time (relative risk 1.02 (95% CI 1.00 to 1.03)) and the combined presence of rheumatoid factor and anticitrullinated protein antibodies (RF+/ACPA+) (3.27 (1.25-8.53)) were significantly correlated with JSN progression. In patients <40 the baseline swollen joint count (SJC; 1.09 (1.01-1.18)) and ESR over time (1.04 (1.02-1.06)) were significantly associated.

CONCLUSIONS

At baseline, patients with RA ≥55 years had more JSN than younger patients but after 10 years JSN scores were similar between age groups. Independent risk factors for JSN progression were baseline SJC and ESR over time in patients <40, RF+/ACPA+ and ESR over time in patients ≥55 years. This suggests that mechanisms leading to JSN progression are related to (residual) rheumatoid inflammation and vary between age groups. These mechanisms remain to be elucidated.

TRIAL REGISTRATION NUMBERS

NTR262, NTR265.

Rheumatoid arthritis phenotype at presentation differs depending on the number of autoantibodies present

Objectives

In rheumatoid arthritis (RA), seropositive and seronegative disease may be two entities with different underlying pathophysiological mechanisms, long-term outcomes and disease presentations. However, the effect of the conjoint presence of multiple autoantibodies, as proxy for a more pronounced humoral autoimmune response, on clinical phenotype remains unclear. Therefore, this study investigates the association between the number of autoantibodies and initial clinical presentation in two independent cohorts of patients with early RA.

Methods

Autoantibody status (rheumatoid factor, anticitrullinated protein antibodies and anticarbamylated protein antibodies) was determined at baseline in the Leiden Early Arthritis Cohort (n=828) and the Swedish BARFOT (Better Anti-Rheumatic Farmaco-Therapy, n=802) study. The association between the number of autoantibodies and baseline clinical characteristics was investigated using univariable and multivariable ordinal regression.

Results

In both cohorts, the following independent associations were found in multivariable analysis: patients with a higher number of RA-associated antibodies were younger, more often smokers, had a longer symptom duration and a higher erythrocyte sedimentation rate at presentation compared with patients with few autoantibodies.

Conclusions

The number of autoantibodies, reflecting the breadth of the humoral autoimmune response, is associated with the clinical presentation of RA. Predisease pathophysiology is thus reflected by the initial clinical phenotype.

Complement levels and anti-C1q autoantibodies in patients with neuropsychiatric systemic lupus erythematosus

Objective

The objective of this paper is to analyse serum levels of anti-C1q, C1q circulating immune complexes (CIC), complement activation and complement components in systemic lupus erythematosus (SLE) patients during the first central nervous system neuropsychiatric (NP) event and to define the possible association between these results and clinical and laboratory characteristics.

Methods

A total of 280 patients suspected of having NP involvement due to SLE were recruited in the Leiden NPSLE-clinic. All SLE patients were classified according to the ACR 1982 revised criteria for the classification of SLE. The clinical disease activity was measured by the SLE Disease Activity Index 2000 (SLEDAI-2K) and NP diagnoses were classified according to the 1999 ACR case definitions for NPSLE. We measured in serum of all patients anti-C1q and C1q CIC levels, the activation capacity of complement (CH50 and AP50) and different complement components (C1q, C3, C4).

Results

In 92 patients the symptoms were attributed to SLE. NPSLE patients consisted of 63 patients with focal NPSLE and 34 patients with diffuse NPSLE. Anti-C1q antibodies were significantly higher and CH50, AP50 and C3 were significantly lower in NPSLE patients compared with SLE patients without NPSLE. This association was specially marked for diffuse NPSLE while no differences were found for focal NPSLE. After using potential predictors, decreased C4 remained significantly associated with focal NPSLE, but only when antiphospholipid antibodies (aPL) were included in the model. C3 and AP50 were independently associated with diffuse NPSLE. When SLEDAI-2K was included in the model these two associations were lost. When individual NPSLE syndromes were analysed, psychosis and cognitive dysfunction showed significantly lower values of complement activation capacity and all complement components. No significant associations were seen for other individual NPSLE syndromes.

Conclusion

The associations between diffuse NPSLE and anti-C1q, C3/AP50 and focal NPSLE and C4 may be explained by disease activity and the presence of aPL, respectively. The role of complement activation and complement components in lupus psychosis and cognitive dysfunction merits further research.

The association between anti-carbamylated protein (anti-CarP) antibodies and radiographic progression in early rheumatoid arthritis: a study exploring replication and the added value to ACPA and rheumatoid factor

Objective

Anti-carbamylated protein (anti-CarP) antibodies are reported to associate with more radiographic progression within the total rheumatoid arthritis (RA) population and anti-citrullinated peptide antibody (ACPA)-negative subgroup. We explored the association of anti-CarP with radiographic progression in RA and aimed to replicate the association and evaluate the added value of anti-CarP antibodies in relation to ACPA and rheumatoid factor (RF).

Methods

576 Swedish and 628 Dutch patients with RA (2394 and 3247 sets of radiographs, respectively) were longitudinally studied. Replication was restricted to the Swedish patients. In both cohorts, the association of anti-CarP with radiographic progression was determined in strata of patients with similar ACPA and RF status; results of both cohorts were combined in fixed-effect meta-analyses. The net percentage of patients for whom the radiographic progression in 5 years was additionally correctly classified when adding anti-CarP to a model including ACPA and RF was evaluated.

Results

Anti-CarP associated with radiographic progression in the total Swedish RA population (beta=1.11 per year, p=8.75×10−13) and in the ACPA-negative subgroup (beta=1.14 per year, p=0.034). Anti-CarP associated with more radiographic progression in the strata of ACPA-positive/RF-negative, ACPA-negative/RF-positive and ACPA-positive/RF-positive patients with RA (respective p values 0.014, 0.019 and 0.0056). A model including ACPA and RF correctly classified 54% and 57% of the patients; adding anti-CarP to this model did not increase these percentages (54% and 56% were correctly classified).

Conclusions

Anti-CarP antibodies associated with more severe radiographic progression in the total and ACPA-negative RA population. Anti-CarP-positivity had a statistically significant additive value to ACPA and RF, but did not improve correct classification of patients.

Efficacy of etanercept in combination with methotrexate in moderate-to-severe rheumatoid arthritis is not dependent on methotrexate dosage

Objective

To evaluate the impact of methotrexate (MTX) dosage on clinical, functional and quality of life outcomes in patients with rheumatoid arthritis (RA) from two previous etanercept (ETN) trials after 24 months of treatment.

Methods

Patients with active RA in the ETN+MTX combination treatment arms of the Trial of Etanercept and Methotrexate with Radiographic Patient Outcomes (TEMPO) and COmbination of Methotrexate and ETanercept in Active Early Rheumatoid Arthritis (COMET) studies were pooled in this post hoc analysis and stratified by MTX dosage at 24 months, having MTX monotherapy groups as control: low dose, <10.0 mg/week; medium dose, 10.0–17.5 mg/week; and high dose, >17.5 mg/week. Data from these patient subgroups were included in descriptive summaries of demographic and disease characteristics at baseline. The following outcomes at 24 months were also evaluated for each subgroup: Disease Activity Score in 28 joints (DAS28) low disease activity (LDA) and remission; American College of Rheumatology 20%, 50% and 70% improvement criteria (ACR20, 50 and 70) responses; and changes from baseline in DAS28, Health Assessment Questionnaire Disease Index (HAQ-DI) and EuroQol 5-dimensions visual analogue scale (EQ-5D VAS).

Results

Baseline demographics were similar between the low, medium and high MTX dose groups in the ETN+MTX combination and MTX monotherapy arms, with the exception of disease duration (ETN+MTX low 5.5; medium 5.1; high 0.8 years vs MTX low 8.3; medium 4.7; high 0.8 years). Responses to ETN+MTX combination therapy at 24 months were consistently high across MTX dosage groups, with very similar rates of DAS28 LDA/remission and ACR20/50/70. Improvements in DAS28, HAQ-DI and EQ-5D VAS were also not dependent on MTX dosage in the combination treatment arm.

Conclusions

Patients with RA in the TEMPO and COMET trials who received ETN+MTX showed similar efficacy outcomes at 24 months, regardless of MTX dosage.

Trial registration numbers

NCT00195494 (COMET) and NCT00393471 (TEMPO).

Anticitrullinated protein antibodies and rheumatoid factor are associated with increased mortality but with different causes of death in patients with rheumatoid arthritis: a longitudinal study in three European cohorts

OBJECTIVE

Patients with rheumatoid arthritis (RA)-related autoantibodies have an increased mortality rate. Different autoantibodies are frequently co-occurring and it is unclear which autoantibodies associate with increased mortality. In addition, association with different causes of death is thus far unexplored. Both questions were addressed in three early RA populations.

METHODS

2331 patients with early RA included in Better Anti-Rheumatic Farmaco-Therapy cohort (BARFOT) (n=805), Norfolk Arthritis Register (NOAR) (n=678) and Leiden Early Arthritis Clinic cohort (EAC) (n=848) were studied. The presence of anticitrullinated protein antibodies (ACPA), rheumatoid factor (RF) and anticarbamylated protein (anti-CarP) antibodies was studied in relation to all-cause and cause-specific mortality, obtained from national death registers. Cox proportional hazards regression models (adjusted for age, sex, smoking and inclusion year) were constructed per cohort; data were combined in inverse-weighted meta-analyses.

RESULTS

During 26 300 person-years of observation, 29% of BARFOT patients, 30% of NOAR and 18% of EAC patients died, corresponding to mortality rates of 24.9, 21.0 and 20.8 per 1000 person-years. The HR for all-cause mortality (95% CI) was 1.48 (1.22 to 1.79) for ACPA, 1.47 (1.22 to 1.78) for RF and 1.33 (1.11 to 1.60) for anti-CarP. When including all three antibodies in one model, RF was associated with all-cause mortality independent of other autoantibodies, HR 1.30 (1.04 to 1.63). When subsequently stratifying for death cause, ACPA positivity associated with increased cardiovascular death, HR 1.52 (1.04 to 2.21), and RF with increased neoplasm-related death, HR 1.64 (1.02 to 2.62), and respiratory disease-related death, HR 1.71 (1.01 to 2.88).

CONCLUSIONS

The presence of RF in patients with RA associates with an increased overall mortality rate. Cause-specific mortality rates differed between autoantibodies: ACPA associates with increased cardiovascular death and RF with death related to neoplasm and respiratory disease.

Differential TLR-induced cytokine production by human mast cells is amplified by FcɛRI triggering

BACKGROUND

Mast cells are mainly present in strategic locations, where they may have a role in defence against parasites and bacteria. These pathogens can be recognized by mast cells via Toll-like receptors (TLR). Allergic symptoms are often increased in the presence of pathogens at the site of allergen exposure, but it is unknown which cytokines can mediate such an effect.

OBJECTIVE

To study whether an interaction between IgE- and TLR-mediated activation of human mast cells can contribute to exacerbated inflammatory responses.

METHODS

Peripheral blood-derived mast cells were stimulated with TLR ligands, in the presence or absence of anti-IgE triggering, after which degranulation was measured using flow cytometry and cytokine production was evaluated by multiplex assays, and ELISA. For evaluation of allergen-specific responses, mast cells were sensitized with serum of allergic individuals or controls, after which they were stimulated using allergens in combination with TLR ligands.

RESULTS

Simultaneous triggering of mast cells via IgE and TLR ligands greatly enhanced cytokine production but not IgE-induced degranulation. Different TLR ligands specifically enhanced the differential production of cytokines in conjunction with FcεRI triggering. Importantly, only TLR-4 and TLR-6 were able to induce robust production of IL-13, an important molecule in allergic reactions.

CONCLUSIONS & CLINICAL RELEVANCE

These results indicate that the simultaneous presence of pathogen- or danger-associated signals and FcεRI triggering via specific IgE can significantly modify mast cell-mediated allergic reactions via synergistic production of cytokines and inflammatory mediators and provide an explanation of augmented allergic symptoms during infection.

IL2RA is associated with persistence of rheumatoid arthritis

INTRODUCTION

Although rheumatoid arthritis (RA) is generally a chronic disease, a proportion of RA-patients achieve disease-modifying antirheumatic drug (DMARD)-free sustained remission, reflecting loss of disease-persistence. To explore mechanisms underlying RA-persistence, we performed a candidate gene study. We hypothesized that variants associating with lack of radiographic progression also associate with DMARD-free sustained remission.

METHODS

645 Dutch RA-patients were studied on DMARD-free sustained remission during a maximal follow-up duration of 10-years. Variants associated with radiographic progression under an additive model in the total RA-population (Human Leukocyte Antigens (HLA)-DRB1-shared epitope (SE), Dickkopf-1 (DKK1)-rs1896368, DKK1-rs1896367, DKK1-rs1528873, C5Orf30-rs26232, Interleukin-2 receptor-α (IL2RA)-rs2104286, Matrix metalloproteinase-9 (MMP-9)-rs11908352, rs451066 and Osteoprotegerin (OPG)-rs1485305) were studied. Cox-regression analyses were performed and Bonferroni correction applied. Soluble IL2Rα (sIL2Rα)-levels were studied. For replication, 622 RA-patients included in the French Evaluation et Suivi de POlyarthrites Indifférenciées Récentes cohort (ESPOIR)-cohort were investigated. Results were combined in inverse-variance weighted meta-analysis.

RESULTS

Similar as previously reported, the SE-alleles associated with less remission (hazard ratio (HR) = 0.57, 95 % confidence interval (95 % CI) = 0.42-0.77, p = 2.72×10(-4)). Variants in DKK-1, C5orf30, MMP-9 and OPG were not associated with remission. The IL2RA-rs2104286 minor allele associated with a higher chance on remission (HR = 1.52, 95 % CI = 1.16-1.99, p = 2.44×10(-3)). The rs2104286 minor allele associated with lower sIL2Rα-levels (p = 1.44×10(-3)); lower sIL2Rα-levels associated with a higher chance on remission (HR per 100 pg/L = 0.81, 95 % CI = 0.68-0.95, p = 0.012). When including rs2104286 and sIL2Rα-levels in one analysis, the HR for rs2104286 was 2.27 (95 % CI = 1.06-4.84, p = 0.034) and for sIL2Rα 0.83 (95 % CI = 0.70-0.98, p = 0.026). Within ESPOIR, the HR of rs2104286 was 1.31 (95 % CI = 0.90-1.90). The meta-analysis revealed a p-value of 1.01×10(-3).

CONCLUSION

IL2RA-rs2104286 and sIL2Rα-level associated with RA-persistence. IL2RA variants are known to protect against multiple sclerosis, diabetes mellitus and RA. Besides HLA-SE, IL2RA-rs2104286 is thus far the only known genetic variant associated with both joint destruction and RA-persistence. This underlines the relevance of IL2RA for RA.

Biomarkers for radiographic progression in rheumatoid arthritis

Treatment of patients with rheumatoid arthritis (RA) is rarely personalized, since predictors of disease course are lacking. The severity of RA can be measured objectively by radiographic progression. The most reliable way to measure radiographic progression is in a longitudinal cohort with serial time points, scoring on a quantitative scale, with a validated scoring method and trained readers. Current models used to predict radiographic progression are based on C-reactive protein and anti-citrullinated protein antibodies. Other biomarkers could increase the prognostic ability of these models. In this review, we evaluated the published (and partly nonpublished) data on genetic, serologic, and imaging biomarkers for the severity of joint destruction in RA. We evaluated variants in 10 genes (CD40, IL2RA, IL4R, IL15, OPG, DKK1, SOST, GRZB, MMP9, and SPAG16). In 5 variants (IL2RA, DKK1, GRZB, MMP9, and SPAG16), we found evidence of an association at the functional level. We evaluated several serological biomarkers, namely, autoantibodies (RF, ACPA, anti-CarP), markers related to inflammation (ESR, CRP), and proteinases or components of the extracellular matrix of bone and cartilage (MMP3, CTX-I, CTX-II, COMP, TIMP1, PYD, RANKL/OPG, CXCL13). Finally, we evaluated markers that can be visualized by ultrasound or MRI, including erosions, bone marrow edema, synovitis, and tenosynovitis. Several studies showed that bone marrow edema and synovitis on MRI are robust predictors of radiographic progression. Some studies showed that inflammation detected with ultrasound predicted radiographic progression. Future studies will reveal whether adding and combining all these different biomarkers will increase the accuracy of risk models predicting radiographic progression in RA.

Association of valine and leucine at HLA-DRB1 position 11 with radiographic progression in rheumatoid arthritis, independent of the shared epitope alleles but not independent of anti-citrullinated protein antibodies

OBJECTIVE

For decades it has been known that the HLA-DRB1 shared epitope (SE) alleles are associated with an increased risk of development and progression of rheumatoid arthritis (RA). Recently, the following variations in the peptide-binding grooves of HLA molecules that predispose to RA development have been identified: Val and Leu at HLA-DRB1 position 11, Asp at HLA-B position 9, and Phe at HLA-DPB1 position 9. This study was undertaken to investigate whether these variants are also associated with radiographic progression in RA, independent of SE and anti-citrullinated protein antibody (ACPA) status.

METHODS

A total of 4,911 radiograph sets from 1,878 RA patients included in the Leiden Early Arthritis Clinic (The Netherlands), Umeå (Sweden), Hospital Clinico San Carlos-Rheumatoid Arthritis (Spain), and National Data Bank for Rheumatic Diseases (US) cohorts were studied. HLA was imputed using single-nucleotide polymorphism data from an Immunochip, and the amino acids listed above were tested in relation to radiographic progression per cohort using an additive model. Results from the 4 cohorts were combined in inverse-variance weighted meta-analyses using a fixed-effects model. Analyses were conditioned on SE and ACPA status.

RESULTS

Val and Leu at HLA-DRB1 position 11 were associated with more radiographic progression (meta-analysis P = 5.11 × 10(-7)); this effect was independent of SE status (meta-analysis P = 0.022) but not independent of ACPA status. Phe at HLA-DPB1 position 9 was associated with more severe radiographic progression (meta-analysis P = 0.024), though not independent of SE status. Asp at HLA-B position 9 was not associated with radiographic progression.

CONCLUSION

Val and Leu at HLA-DRB1 position 11 conferred a risk of a higher rate of radiographic progression independent of SE status but not independent of ACPA status. These findings support the relevance of these amino acids at position 11.

Personalized medicine in rheumatoid arthritis: is the glass half full or half empty?

The care of patients with rheumatoid arthritis (RA) has been revolutionized since the 1990s. Strict monitoring and disease control based on measurement of signs and symptoms towards a target of low disease activity have improved outcome of patients enormously. As a result of treatment strategies based upon individualized measurement of disease activity, the clinical view of RA has changed from a destructive autoimmune disease (with a median joint damage of >10 Sharp units per year) to a condition in which significant damage can be prevented in the majority of patients. Moreover, a large number of targeted therapies (tumour necrosis factor, IL6, CD80/CD86 and CD20 inhibitors) have become available to better treat the underlying disease process. However, identification of the underlying pathways that drive the disease process in an individual patient has been relatively unsuccessful, implying that no predictive factors have been identified to guide the choice of a specific treatment. Distinct subsets of RA patients have been identified, based on the presence or absence of anticitrullinated protein antibodies (ACPAs). These two subsets are associated with different environmental and genetic risk factors, histology and disease outcome (a more destructive disease course with more persistent joint inflammation is observed when ACPAs are present). Therefore, it is recommended that treatment should be guided towards a more consistently low level of disease activity in the presence of ACPAs than in the absence of the antibodies.

Translation, cross-cultural adaptation, and validation of the UCLA Scleroderma Clinical Trial Consortium Gastrointestinal Tract Instrument (SCTC GIT) 2.0 into Dutch

OBJECTIVES

To translate and adapt the University of California, Los Angeles Scleroderma Clinical Trial Consortium Gastrointestinal Tract Instrument 2.0 (UCLA SCTC GIT 2.0) into Dutch and validate it among Dutch systemic sclerosis (SSc) patients.

METHODS

First, the UCLA SCTC GIT 2.0 questionnaire was translated and adapted according to international guidelines. The resulting Dutch GIT 2.0 was, in combination with the SSc Health Assessment Questionnaire (SHAQ) and Short Form-36 (SF-36) administered to SSc patients participating in a standardised medical assessment. Moreover, all previous clinical examinations and confirmed medical diagnoses related to GIT were extracted from the medical records. Internal consistency was determined by calculating Cronbach's alpha. To determine the reliability, the questionnaire was re-administered with an interval of two weeks to a subgroup of patients and the intraclass-correlation coefficient (ICC) was computed. Spearman correlation coefficients between GIT scores, SF-36 and SHAQ were computed. GIT scores were compared among patients with and without previous gastrointestinal examinations and/or diagnoses.

RESULTS

Eighty-nine patients with a mean age of 53.6 (SD 12) years, and predominantly female (76%) were included. The median total GIT score was 0.17 (Cronbach's alpha 0.921). The test-retest reliability of the total GIT score was good (n=27; ICC 0.749). Overall, the GIT total scores correlated significantly with the SHAQ visual analogue scale intestinal complaints and the SF-36. Significant differences between GIT total and subscale scores of patients with and without previous gastrointestinal examinations and diagnoses were present.

CONCLUSIONS

The Dutch GIT 2.0 questionnaire showed good internal consistency, construct validity and test-retest reliability.

Degree of synovitis on MRI by comprehensive whole knee semi-quantitative scoring method correlates with histologic and macroscopic features of synovial tissue inflammation in knee osteoarthritis

OBJECTIVE

To evaluate the association between synovitis on contrast enhanced (CE) MRI with microscopic and macroscopic features of synovial tissue inflammation.

METHOD

Forty-one patients (mean age 60 years, 61% women) with symptomatic radiographic knee OA were studied: twenty underwent arthroscopy (macroscopic features were scored (0-4), synovial biopsies obtained), twenty-one underwent arthroplasty (synovial tissues were collected). After haematoxylin and eosin staining, the lining cell layer, synovial stroma and inflammatory infiltrate of synovial tissues were scored (0-3). T1-weighted CE-MRI's (3 T) were used to semi-quantitatively score synovitis at 11 sites (0-22) according to Guermazi et al. Spearman's rank correlations were calculated.

RESULTS

The mean (SD) MRI synovitis score was 8.0 (3.7) and the total histology grade was 2.5 (1.6). Median (range) scores of macroscopic features were 2 (1-3) for neovascularization, 1 (0-3) for hyperplasia, 2 (0-4) for villi and 2 (0-3) for fibrin deposits. The MRI synovitis score was significantly correlated with total histology grade [r = 0.6], as well as with lining cell layer [r = 0.4], stroma [r = 0.3] and inflammatory infiltrate [r = 0.5] grades. Moreover, MRI synovitis score was also significantly correlated with macroscopic neovascularization [r = 0.6], hyperplasia [r = 0.6] and villi [r = 0.6], but not with fibrin [r = 0.3].

CONCLUSION

Synovitis severity on CE-MRI assessed by a new whole knee scoring system by Guermazi et al. is a valid, non-invasive method to determine synovitis as it is significantly correlated with both macroscopic and microscopic features of synovitis in knee OA patients.

Mortality in osteoarthritis patients

OBJECTIVES

To investigate whether all-cause mortality and deaths due to cardiovascular disease are increased in patients who have consulted primary or secondary health care with symptoms and signs of osteoarthritis (OA).

METHOD

This study included 383 patients with symptomatic OA at multiple sites from the Genetics ARthrosis and Progression (GARP) study (mean age 60 years, 82% women, 3693 person-years of follow-up) and 459 patients with primary hand, knee, or hip OA from the Osteoarthritis Care Clinic (OCC) study (mean age 61 years, 88% women, 1890 person-years of follow-up). Standardized mortality ratios (SMRs) with 95% confidence intervals (CIs) were calculated for all-cause mortality and causes of deaths in comparison to the general population. Cox proportional hazard ratios (HRs) with 95% CIs were used to associate baseline characteristics with all-cause mortality.

RESULTS

In the GARP study, 26 patients died whereas 48 deaths were expected (SMR 0.54, 95% CI 0.37-0.79). The SMR was 0.47 (95% CI 0.29-0.76) in women and 0.73 (95% CI 0.39-1.35) in men. Similar results were found in the OCC study (SMR 0.45, 95% CI 0.25-0.82). Malignancy and cardiovascular disease were the main causes of deaths in GARP. Male sex (HR 3.04, 95% CI 1.38-6.69), increasing age (HR 1.10, 95% CI 1.05-1.16), and self-reported cancer (HR 8.29, 95% CI 3.12-22.03) were associated with increased mortality in GARP.

CONCLUSIONS

Patients consulting health care for their OA are not at higher risk of death than the general population. These results suggest that the management of OA patients may not need to focus specifically on the treatment of cardiovascular risk factors and comorbidities.

Clinical and radiographic outcomes at 2 years and the effect of tocilizumab discontinuation following sustained remission in the second and third year of the ACT-RAY study

Objective

To assess the efficacy and safety of tocilizumab (TCZ) plus methotrexate/placebo (MTX/PBO) over 2 years and the course of disease activity in patients who discontinued TCZ due to sustained remission.

Methods

ACT-RAY was a double-blind 3-year trial. Patients with active rheumatoid arthritis despite MTX were randomised to add TCZ to ongoing MTX (add-on strategy) or switch to TCZ plus PBO (switch strategy). Using a treat-to-target approach, open-label conventional synthetic disease-modifying antirheumatic drugs (csDMARDs), other than MTX, were added from week 24 if Disease Activity Score in 28 joints based on erythrocyte sedimentation rate (DAS28-ESR) >3.2. Between weeks 52 and 104, patients in sustained clinical remission (DAS28-ESR <2.6 at two consecutive visits 12 weeks apart) discontinued TCZ and were assessed every 4 weeks for 1 year. If sustained remission was maintained, added csDMARDs, then MTX/PBO, were discontinued.

Results

Of the 556 randomised patients, 76% completed year 2. Of patients entering year 2, 50.4% discontinued TCZ after achieving sustained remission and 5.9% achieved drug-free remission. Most patients who discontinued TCZ (84.0%) had a subsequent flare, but responded well to TCZ reintroduction. Despite many patients temporarily stopping TCZ, radiographic progression was minimal, with differences favouring add-on treatment. Rates of serious adverse events and serious infections per 100 patient-years were 12.2 and 4.4 in add-on and 15.0 and 3.7 in switch patients. In patients with normal baseline values, alanine aminotransferase elevations >3×upper limit of normal were more frequent in add-on (14.3%) versus switch patients (5.4%).

Conclusions

Treat-to-target strategies could be successfully implemented with TCZ to achieve sustained remission, after which TCZ was stopped. Biologic-free remission was maintained for about 3 months, but most patients eventually flared. TCZ restart led to rapid improvement.

Trial registration number

NCT00810199.

CD226 (DNAM-1) is associated with susceptibility to juvenile idiopathic arthritis

OBJECTIVES

Juvenile idiopathic arthritis (JIA) is considered a complex genetic autoimmune disease. We investigated the association of genetic variants previously implicated in JIA, autoimmunity and/or immunoregulation, with susceptibility to JIA.

METHODS

A genetic association study was performed in 639 JIA patients and 1613 healthy controls of northwest European descent. Ninety-three single nucleotide polymorphisms (SNP) were genotyped in a candidate gene approach. Results of the entire JIA patient group (all subtypes) were compared with results obtained, alternatively, with a clinically homogeneous patient group including only oligoarticular and rheumatoid factor (RF) negative polyarticular JIA patients (n=493). Meta-analyses were performed for all SNPs that have been typed in other Caucasian JIA cohorts before.

RESULTS

SNPs in or near PTPN22, VTCN1, the IL2-IL21 region, ANKRD55 and TNFA were confirmed to be associated with JIA (p<0.05), strengthening the evidence for involvement of these genes in JIA. In the majority of these replicated SNPs, effect sizes were larger when analysing a homogeneous patient cohort than when analysing all subtypes. We identified two novel associations with oligoarticular and RF-negative polyarticular JIA: CD226 rs763361 (OR 1.30, 95% CI 1.12 to 1.51, p=0.0006) and CD28 rs1980422 (OR 1.29, 95% CI 1.07 to 1.55, p=0.008). Meta-analyses including reported studies confirmed the association of both SNPs with susceptibility to JIA (OR 1.16, p=0.001 and OR 1.18, p=0.001, for rs763361 and rs1980422, respectively).

CONCLUSIONS

The CD226 gene has been identified as novel association with JIA, and a SNP near CD28 as a suggestive association. Both genes are probable candidate risk factors, since they are involved in costimulation of T cells.

A genetic variant in the region of MMP-9 is associated with serum levels and progression of joint damage in rheumatoid arthritis

OBJECTIVES

The severity of joint destruction is highly variable between rheumatoid arthritis (RA) patients. The majority of its heritability is still unexplained. Several autoimmune diseases share genetic risk variants that may also influence disease progression. We aimed to identify genetic risk factors for the severity of joint damage in RA by studying genetic susceptibility loci of several autoimmune diseases.

METHODS

In phase 1, 3143 sets of x-rays of 646 Dutch RA patients taken over 7 years (Sharp van der Heijde (SHS) scored) were studied. Genotyping was done by Immunochip. Associations of single-nucleotide polymorphisms (SNPs) with minor allele frequency (MAF) >0.01 and joint destruction were analysed. In phase 2, 686 North American RA patients with 926 SHS-scored x-rays over 15 years of follow-up were evaluated. In both phases multiple testing corrections were done for the number of uncorrelated SNPs; the thresholds for significance were p<1.1×10(-6) and p<0.0036. Matrix metalloproteinase 9 (MMP-9) levels were measured with ELISA in baseline serum samples.

RESULTS

In phase 1, 109 SNPs associated significantly with joint destruction (p<1.1×10(-6)). Of these, 76 were located in the HLA region; the 33 non-HLA variants were studied in phase 2. Here two variants were associated with the severity of joint destruction: rs451066 on chromosome 14 (p=0.002, MAF=0.20) and rs11908352 on chromosome 20 (p=0.002, MAF=0.21). Rs11908352 is located near the gene encoding MMP-9. Serum levels of MMP-9 were significantly associated with the rs11908352 genotypes (p=0.007).

CONCLUSIONS

These data indicate that two loci that confer risk to other autoimmune diseases also affect the severity of joint destruction in RA. Rs11908352 may influence joint destruction via MMP-9 production.

Toll-like receptor triggering augments activation of human mast cells by anti-citrullinated protein antibodies

OBJECTIVE

Mast cells may play a role in rheumatoid arthritis (RA), but activation of human mast cells in autoimmune settings has been little studied. Toll-like receptors (TLR) and Fcγ receptors (FcγR) are important receptors for cellular activation in the joint, but expression and stimulation of these receptors in human mast cells or the functional interplay between these pathways is poorly understood. Here, we analysed triggering of human mast cells via these receptors in the context of anti-citrullinated protein antibody-positive (ACPA+) RA.

METHODS

RNA and protein expression of TLRs and FcγR was quantified using PCR and flow cytometry, respectively. Mast cells were stimulated with TLR ligands (including HSP70) combined with IgG immune complexes and IgG-ACPA.

RESULTS

Human mast cells expressed TLRs and produced cytokines in response to TLR ligands. Both cultured and synovial mast cells expressed FcγRIIA, and triggering of this receptor by IgG immune complexes synergised with activation by TLR ligands, leading to two- to fivefold increased cytokine levels. Mast cells produced cytokines in response to ACPA immune complexes in a citrulline-specific manner, which synergised in the presence of HSP70.

CONCLUSIONS

Our data show that synovial mast cells express FcγRIIA and that mast cells can be activated by IgG-ACPA and TLR ligands. Importantly, combined stimulation via TLRs and immune complexes leads to synergy in cytokine production. These findings suggest mast cells are important targets for TLR ligands and immune complexes, and that combined activation of mast cells via these pathways greatly enhances inflammation in synovial tissue of RA patients.

Metabolic profiling reveals differences in concentrations of oxylipins and fatty acids secreted by the infrapatellar fat pad of donors with end-stage osteoarthritis and normal donors

OBJECTIVE

The infrapatellar fat pad (IPFP) in the knee joint is hypothesized to contribute to osteoarthritis (OA) development by the IFPF possibly by influencing inflammatory processes. Oxylipins are essential mediators in the inflammatory process. We undertook this study to investigate secretion by the IFPF of fatty acids and oxylipins derived from those fatty acids.

METHODS

IPFP explants from 13 OA donors undergoing joint replacement surgery and from 10 normal donors postmortem were cultured for 24 hours, and supernatants (fat-conditioned medium [FCM]) were collected. Liquid chromatography tandem mass spectrometry detected fatty acids and oxylipins in FCM samples. Univariate and multivariate (partial least-squares discriminant analysis [PLS-DA]) analyses were performed, followed by pathway analysis. To validate these outcomes, a second set of OA FCM samples was measured (n=23).

RESULTS

Twenty-nine oxylipins and fatty acids could be detected in FCM. Univariate analysis showed no differences between normal donor and OA donor FCM; however, PLS-DA revealed an oxylipin/fatty acid profile consisting of 14 mediators associated with OA (accuracy rate 72%). The most important contributors to the model were lipoxin A4 (decreased), thromboxane B2 (increased), and arachidonic acid (increased). The statistical model predicted 64% of the second set of OA FCM samples correctly. Pathway analysis indicated differences in individual mediators rather than in complete pathways.

CONCLUSION

The IPFP secretes multiple and different oxylipins, and a subset of these oxylipins provides a distinctive profile for OA donors. It is likely that the observed changes are regulated by the OA process rather than being a consequence of basal metabolism changes, as an increase in fatty acid levels was not necessarily associated with an increase in oxylipins derived from that fatty acid.

Clinical, radiographic and immunogenic effects after 1 year of tocilizumab-based treatment strategies in rheumatoid arthritis: the ACT-RAY study

OBJECTIVE

To assess the 1-year efficacy and safety of a regimen of tocilizumab plus methotrexate or placebo, which was augmented by a treat-to-target strategy from week 24.

METHODS

ACT-RAY was a double-blind, 3-year trial. Adults with active rheumatoid arthritis despite methotrexate were randomised to add tocilizumab to ongoing methotrexate (add-on strategy) or to switch to tocilizumab plus placebo (switch strategy). Tocilizumab 8 mg/kg was administered every 4 weeks. Conventional open-label disease-modifying antirheumatic drugs (DMARDs) other than methotrexate were added at week 24 or later in patients with DAS28>3.2.

RESULTS

556 patients were randomised; 85% completed 52 weeks. The proportion of patients receiving open-label DMARDs was comparable in the add-on (29%) and switch (33%) arms. Overall, week 24 results were maintained or further improved at week 52 in both arms. Some endpoints favoured the add-on strategy. Mean changes in Genant-modified Sharp scores were small; more add-on (92.8%) than switch patients (86.1%) had no radiographic progression. At week 52, comparable numbers of patients had antidrug antibodies (ADAs; 1.5% and 2.2% of add-on and switch patients, respectively) and neutralising ADAs (0.7% and 1.8%). Rates of serious adverse events and serious infections per 100 patient-year (PY) were 11.3 and 4.5 in add-on and 16.8 and 5.5 in switch patients. In patients with normal baseline values, alanine aminotransferase elevations >3× upper limit of normal were observed in 11% of add-on and 3% of switch patients.

CONCLUSIONS

Despite a trend favouring the add-on strategy, these data suggest that both tocilizumab add-on and switch strategies led to meaningful clinical and radiographic responses.

Drug-free holiday in patients with rheumatoid arthritis: a qualitative study to explore patients' opinion

Clinical trials have shown that in patients with long-standing low disease activity, tapering and/or stopping antirheumatic medication is a realistic option. The objective of this study is to explore patients' opinion about tapering and discontinuing antirheumatic drugs. This qualitative study is based on interviews with 20 patients with rheumatoid arthritis (RA) about RA treatment and treatment discontinuation through structured interviewing. Interviews were tape-recorded, transcribed verbatim, and screened by three assessors independently for meaning units. Not only positive emotions about drug discontinuation such as hope, happiness, and relief, but also fear and disappointment were mentioned. Some patients expect that drug discontinuation will be possible in other patients and/or themselves, while others do not expect this. The concept of increase in disease activity after discontinuing medication was mentioned, and while patients expect that disease activity will decrease again after restarting medication, they expect that this will take (too much) time. Positive emotions about the option to taper and discontinue antirheumatic medication, with negative expectations is a common combination in these RA patients. In particular, patients expect that disease activity will flare and that improvement upon restarting medication will take time. Patients' expectations and feelings should be addressed before drug tapering is attempted in a clear strategy of continued monitoring of disease activity.

Association of genetic variants in the IL4 and IL4R genes with the severity of joint damage in rheumatoid arthritis: a study in seven cohorts

OBJECTIVE

The progression of joint destruction in rheumatoid arthritis (RA) is determined by genetic factors. Changes in IL4 and IL4R genes have been associated with RA severity, but this finding has not been replicated. This study was undertaken to investigate the association between IL4- and IL4R-tagging single-nucleotide polymorphisms (SNPs) and the progression rate of joint damage in RA in a multicohort candidate gene study.

METHODS

IL4- and IL4R-tagging SNPs (n = 8 and 39, respectively) were genotyped in 600 RA patients for whom 2,846 sets of radiographs of the hands and feet were obtained during 7 years of followup. Subsequently, SNPs significantly associated with the progression of joint damage were genotyped and studied in relation to 3,415 radiographs of 1,953 RA patients; these included data sets from Groningen (The Netherlands), Lund (Sweden), Sheffield (UK), the North American Rheumatoid Arthritis Consortium (US), Wichita (US), and the National Data Bank (US). The relative increase in progression rate per year in the presence of a genotype was determined in each cohort. An inverse variance weighting meta-analysis was performed on the 6 data sets that together formed the replication phase.

RESULTS

In the discovery phase, none of the IL4 SNPs and 7 of the IL4R SNPs were significantly associated with the joint damage progression rate. In the replication phase, 2 SNPs in the IL4R gene were significantly associated with the joint damage progression rate (rs1805011 [P = 0.02] and rs1119132 [P = 0.001]).

CONCLUSION

Genetic variants in IL4R were identified, and their association with the progression rate of joint damage in RA was independently replicated.