[show abstract][hide abstract] ABSTRACT: To investigate whether baseline concentrations of one-carbon metabolism biomarkers are associated with treatment nonresponse and adverse events in rheumatoid arthritis (RA) patients receiving methotrexate (MTX).
A prospective derivation cohort (n = 285) and validation cohort (n = 102) of RA patients receiving MTX were studied. Concentrations of plasma homocysteine, serum vitamin B12 , serum folate, erythrocyte vitamin B6 , and erythrocyte folate were determined at baseline and after 3 months of treatment. Nonresponse after 3 months was assessed using the Disease Activity Score in 28 joints (DAS28) and the European League Against Rheumatism (EULAR) response criteria. Adverse events at 3 months were assessed using biochemical parameters and health status questionnaires. Analyses were corrected for baseline DAS28, age, sex, MTX dose, comedications, and presence of the methylenetetrahydrofolate reductase 677TT genotype.
In the derivation cohort, the mean DAS28 scores at baseline and 3 months were 4.94 and 3.12, respectively, and 78% of patients experienced adverse events. This was similar between the 2 cohorts, despite a lower MTX dose in the validation cohort. Patients with lower levels of erythrocyte folate at baseline had a higher DAS28 at 3 months in both the derivation cohort (β = -0.15, P = 0.037) and the validation cohort (β = -0.20, P = 0.048). In line with these results, lower baseline erythrocyte folate levels were linearly associated with a 3-month DAS28 of >3.2 in both cohorts (derivation cohort, P = 0.049; validation cohort, P = 0.021) and with nonresponse according to the EULAR criteria (derivation cohort, P = 0.066; validation cohort, P = 0.027). None of the other biomarkers (levels at baseline or changes over 3 months) were associated with the DAS28 or treatment nonresponse. Baseline levels of the biomarkers and changes in levels after 3 months were not associated with incidence of adverse events.
A low baseline concentration of erythrocyte folate is associated with high disease activity and nonresponse at 3 months after the start of MTX treatment and could be used in prediction models for MTX outcome. None of the investigated one-carbon metabolism biomarkers were associated with incidence of adverse events at 3 months.
[show abstract][hide abstract] ABSTRACT: Patients with rheumatoid arthritis (RA) carry an excess risk for cardiovascular disease, which is comparable to the risk in patients with type 2 diabetes mellitus. The mechanisms involved are partly related to traditional cardiovascular risk factors, disease-associated inflammation and undertreatment of traditional cardiovascular disease (CVD) risk factors. Since atherosclerosis is an inflammatory disease, the auto-immune mediated inflammation observed in RA patients contributes to increased endothelial dysfunction, oxidative stress and activation and vascular migration of leukocytes. This concept is underscored by the CVD risk reduction that is seen by anti-inflammatory disease modifying anti-rheumatic drugs such as methotrexate and TNFα inhibitors. The evidence for underdiagnosis and undertreatment of traditional CVD risk factors in RA strengthens the potential benefit of structured CVD risk management in these patients. Current cardiovascular guidelines recommend screening and treatment of CVD risk factors in RA patients, without well defined treatment targets. At present, there is a lack of scientific evidence to establish treatment targets for CVD risk factors in RA. Therefore, expanding research regarding screening and treatment of traditional CVD risk factors in RA patients is needed.
[show abstract][hide abstract] ABSTRACT: The folate antagonist methotrexate (MTX) is the anchor drug in the treatment of rheumatoid arthritis. The therapeutic effects of MTX are attributed to the intracellular levels of MTX, present in the cell as polyglutamates (MTXPGn). We developed a new liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS)-based assay to separately quantitate MTXPGn in red blood cells using stable-isotope-labelled internal standards. Samples were analyzed by LC-ESI-MS/MS using a Waters Acquity UPLC BEH C18 column with a 5-100% organic gradient of 10 mM ammonium bicarbonate (pH 10) and methanol. The analysis consisted of simple sample preparation and a 6-min run time. Detection was done using a Waters Acquity UPLC coupled to a Waters Quattro Premier XE with electrospray ionization operating in the positive ionization mode. Assay validation was performed following recent Food and Drug Administration guidelines. The method was linear from 1-1,000 nM for all MTXPGn (R (2) > 0.99). The coefficient of variation ranged from 1-4% for intraday precision and 6-15% for interday precision. Samples were stable for at least 1 month at -80 °C. Recovery ranged from 98-100%, and the relative matrix-effect varied from 95-99%. The lower limit of quantitation was 1 nM for each MTXPGn. Fifty patient samples from the tREACH study were analyzed. The MTXPGn concentration and distribution of these samples were comparable with values reported in literature. The developed LC-ESI-MS/MS method for the quantitative measurement of MTXPGn in red blood cells is both sensitive and precise within the clinically relevant range. The method can be easily applied in clinical laboratories due to the combination of simple pre-treatment with robust LC-ESI-MS/MS.
Analytical and Bioanalytical Chemistry 12/2012; · 3.66 Impact Factor
[show abstract][hide abstract] ABSTRACT: Glucocorticoid (GC) sensitivity is highly variable among individuals and has been associated with susceptibility to develop (auto-)inflammatory disorders. The purpose of the study was to assess GC sensitivity in Behçet's disease (BD) by studying the distribution of four GC receptor (GR) gene polymorphisms and by measuring in vitro cellular GC sensitivity.
Healthy controls and patients with BD in three independent cohorts were genotyped for four functional GR gene polymorphisms. To gain insight into functional differences in in vitro GC sensitivity, 19 patients with BD were studied using two bioassays and a whole-cell dexamethasone-binding assay. Finally, mRNA expression levels of GR splice variants (GR-α and GR-β) were measured.
Healthy controls and BD patients in the three separate cohorts had similar distributions of the four GR polymorphisms. The Bcll and 9β minor alleles frequency differed significantly between Caucasians and Mideast and Turkish individuals. At the functional level, a decreased in vitro cellular GC sensitivity was observed. GR number in peripheral blood mononuclear cells was higher in BD compared with controls. The ratio of GR-α/GR-β mRNA expression levels was significantly lower in BD.
Polymorphisms in the GR gene are not associated with susceptibility to BD. However, in vitro cellular GC sensitivity is decreased in BD, possibly mediated by a relative higher expression of the dominant negative GR-β splice variant. This decreased in vitro GC sensitivity might play an as yet unidentified role in the pathophysiology of BD.
[show abstract][hide abstract] ABSTRACT: Both Th1 cells and Th17 cells have been recognized in rheumatoid arthritis (RA); however, it remains unclear whether Th1 cells and/or Th17 cells are involved in driving disease chronicity and destructiveness. The aim of this study was to identify and characterize the functional role of Th17 cells in early RA.
Flow cytometry analysis was performed on peripheral blood mononuclear cells (PBMCs) from treatment-naive patients with early RA and age-matched healthy volunteers. PBMCs from these patients, naive T cells, and primary CCR6- Th1 cells and CCR6+ Th17 cells were sorted and cultured in the absence or presence of synovial fibroblasts from patients with early RA (RASFs), and cytokine expression and gene transcription were analyzed. In addition, tumor necrosis factor α (TNFα)- and interleukin-17A (IL-17A)-blocking experiments were performed.
In the PBMCs of treatment-naive patients with early RA, an increased fraction of IL-17A-and TNFα-producing CCR6+ Th17 cells was observed. When cocultured with RASFs, these primary Th17 cells were potent inducers of IL-6 and IL-8 and the tissue-destructive enzymes matrix metalloproteinase 1 (MMP-1) and MMP-3, whereas primary Th1 cells or naive T cells were not. Importantly, specific up-regulation of IL-17A but not TNFα or interferon-γ was observed in RASF/Th17 cell cocultures. In addition to TNFα blocking, IL-17A neutralization was required to further down-regulate Th17 activity in RASF/Th17 cell cocultures.
Th17 cells, but not Th1 cells, cooperated with RASFs in a proinflammatory feedback loop, revealing a potential mechanism by which human Th17 cells drive chronic destructive disease in patients with RA. Furthermore, the neutralization of IL-17A activity is essential in current anti-TNF therapies to suppress Th17 cell activity in patients with early RA and potentially other Th17 cell-mediated disorders.
[show abstract][hide abstract] ABSTRACT: To evaluate the implementation of an intensive group exercise program in patients with rheumatoid arthritis (RA).
In 4 regions in The Netherlands, the Rheumatoid Arthritis Patients In Training exercise program was implemented on a limited scale. Evaluation using the RE-AIM model included: Reach, the proportion of the target population participating; Efficacy, effects on muscle strength, aerobic capacity, functional ability, and psychological functioning; Adoption, program adoption by stakeholders; Implementation, intervention quality (quality audits); and Maintenance, stakeholders' willingness to continue the program in the future.
Twenty-five physical therapists from 14 practices were trained to provide the program. In total, 150 RA patients were recruited (by estimation, 2% of the target population). Of the 81 patients who had finished the 12-month intervention and were available for followup directly after the intervention, 62 patients provided clinical data. Muscle strength improved significantly, whereas aerobic capacity, functional ability, psychological functioning, and disease activity did not change. All 9 informed local patient organizations facilitated patient recruitment, and 35 of 51 rheumatologists involved referred one or more patients. All 10 approached health insurance companies funded the program for 12 months. The quality audits showed sufficient quality in 9 of 12 practices. All of the providers of the program were willing to provide the program in the future, whereas future reimbursement by health insurance companies remained unclear.
The implementation of an intensive exercise program for RA patients on a limited scale can be considered successful regarding its reach, adoption, and implementation. The limited effectiveness and the limited data regarding maintenance warrant additional research.
[show abstract][hide abstract] ABSTRACT: To examine the immunologic mechanism by which 1,25-dihydroxyvitamin D(3) (1,25[OH](2)D(3)) may prevent corticosteroid-induced osteoporosis in patients with early rheumatoid arthritis (RA), with a focus on T cell biology.
Peripheral blood mononuclear cells (PBMCs) and CD4+CD45RO+ (memory) and CD4+CD45RO- (non-memory) T cells separated by fluorescence-activated cell sorting (FACS) from treatment-naive patients with early RA were stimulated with anti-CD3/anti-CD28 in the absence or presence of various concentrations of 1,25(OH)(2)D(3), dexamethasone (DEX), and 1,25(OH)(2)D(3) and DEX combined. Levels of T cell cytokines were determined by enzyme-linked immunosorbent assay and flow cytometry.
The presence of 1,25(OH)(2)D(3) reduced interleukin-17A (IL-17A) and interferon-gamma levels and increased IL-4 levels in stimulated PBMCs from treatment-naive patients with early RA. In addition, 1,25(OH)(2)D(3) had favorable effects on tumor necrosis factor alpha (TNFalpha):IL-4 and IL-17A:IL-4 ratios and prevented the unfavorable effects of DEX on these ratios. Enhanced percentages of IL-17A- and IL-22-expressing CD4+ T cells and IL-17A-expressing memory T cells were observed in PBMCs from treatment-naive patients with early RA as compared with healthy controls. Of note, we found no difference in the percentage of CD45RO+ and CD45RO- cells between these 2 groups. Interestingly, 1,25(OH)(2)D(3), in contrast to DEX, directly modulated human Th17 polarization, accompanied by suppression of IL-17A, IL-17F, TNFalpha, and IL-22 production by memory T cells sorted by FACS from patients with early RA.
These data indicate that 1,25(OH)(2)D(3) may contribute its bone-sparing effects in RA patients taking corticosteroids by the modulation of Th17 polarization, inhibition of Th17 cytokines, and stimulation of IL-4.
[show abstract][hide abstract] ABSTRACT: The glucocorticoid receptor (GR) plays an important regulatory role in the immune system. Four polymorphisms in the GR gene are associated with differences in glucocorticoid (GC) sensitivity; the minor alleles of the polymorphisms N363 S and BclI are associated with relative hypersensitivity to GCs, while those of the polymorphisms ER22/23EK and 9β are associated with relative GC resistance. Because differences in GC sensitivity may influence immune effector functions, we examined whether these polymorphisms are associated with the susceptibility to develop Rheumatoid Arthritis (RA) and RA disease severity.
The presence of GR polymorphisms was assessed in healthy controls (n = 5033), and in RA patients (n = 368). A second control group (n = 532) was used for confirmation of results. In RA patients, the relationship between GR polymorphisms and disease severity was examined.
Carriers of the N363 S and BclI minor alleles had a lower risk of developing RA: odds ratio (OR) = 0.55 (95% confidence interval (CI) 0.32-0.96, P = 0.032) and OR = 0.73 (95% CI 0.58-0.91, P = 0.006), respectively. In contrast, 9β minor allele carriers had a higher risk of developing RA: OR = 1.26 (95% CI 1.00-1.60, P = 0.050). For ER22/23EK minor allele carriers a trend to an increased risk OR = 1.42 (95% CI 0.95-2.13, P = 0.086) was found. All ER22/23EK carriers (32/32) had erosive disease, while only 77% (259/336) of the non-carriers did (P = 0.008). In addition, ER22/23EK carriers were treated more frequently with anti-tumor necrosis factor-alpha (TNFα) therapy (P < 0.05).
The minor alleles of the 9β and ER22/23EK polymorphisms seem to be associated with increased predisposition to develop RA. Conversely, the minor alleles of the N363 S and BclI polymorphisms are associated with reduced susceptibility to develop RA. These opposite associations suggest that constitutionally determined GC resistance may predispose to development of auto-immunity, at least in RA, and vice versa.
Arthritis research & therapy 01/2010; 12(4):R159. · 4.27 Impact Factor
[show abstract][hide abstract] ABSTRACT: To review the diagnostic and prognostic value of anti-mutated citrullinated vimentin (MCV) in rheumatoid arthritis, taking into account the already available serology.
Medline was searched via PubMed (1966 to May 2008) for anti-MCV and related terms, arthritis and arthropathies. Studies with anti-MCV, arthritis/arthropathy, and primary data on diagnosis and/or prognosis were included. Their methodological quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) instrument for diagnostic studies and the modified Hayden list for prognostic studies.
Of 14 eligible studies, 11 included diagnostic data and 3 included prognostic data. No study evaluated anti-MCV as an added diagnostic test to the already available anti-cyclic citrullinated peptide (CCP) and rheumatoid factor serology. One study included the optimal patient spectrum resulting in a sensitivity of 0.59 and specificity of 0.98. A total of 10 diagnostic case-control studies using the same anti-MCV kit showed a sensitivity of 0.64-0.84 and a specificity of 0.79-0.96. This almost equalled the performance of anti-CCP in the same studies. The prognostic evaluation of anti-MCV was limited by differences in study methodology, outcome and statistical modelling. Individual studies showed moderate associations for anti-MCV and radiological progression with the strength of the association comparable to that of anti-CCP.
Study heterogeneity, choice of study population and methodological limitations limited overall conclusions about the true diagnostic and prognostic test performance of anti-MCV. Evidence from the diagnostic case-control studies suggests that anti-MCV may be used as an alternative for anti-CCP.
Annals of the rheumatic diseases 04/2009; 69(2):337-44. · 8.11 Impact Factor
[show abstract][hide abstract] ABSTRACT: To determine whether changes in levels of anti-cyclic citrullinated peptide (anti-CCP) and rheumatoid factor (RF) are associated with the spontaneous improvement of rheumatoid arthritis (RA) during pregnancy and with the subsequent flare post partum.
Disease activity scores from the Pregnancy-induced Amelioration of Rheumatoid Arthritis (PARA) study of 118 patients were available for analysis. Before conception (if applicable), at each trimester and at 6, 12 and 26 weeks post partum, levels of the autoantibodies anti-CCP, IgM-RF, IgG-RF and IgA-RF were determined. Responses in disease activity were classified according to European League Against Rheumatism (EULAR) response criteria during pregnancy and post partum, and associated with the presence or absence of autoantibodies.
The median levels of anti-CCP and all subclasses of RF during pregnancy were stable, whereas post partum the levels of anti-CCP, IgM-RF and IgA-RF declined. A significantly higher percentage of women without autoantibodies (negative for anti-CCP and RF) improved compared with women positive for either or both autoantibodies (75% vs 39%, p = 0.01). The occurrence of a flare post partum was comparable between these groups.
Improvement of disease activity of RA during pregnancy was not associated with changes in levels of autoantibodies during pregnancy, however, improvement may occur more frequently in the absence of anti-CCP and RF.
Annals of the rheumatic diseases 04/2009; 69(2):420-3. · 8.11 Impact Factor
[show abstract][hide abstract] ABSTRACT: To investigate the effectiveness of 4 different treatment strategies for recent-onset rheumatoid arthritis (RA) on 2-year patient-reported outcomes, including functioning and quality of life.
A total of 508 patients with recent-onset RA were randomly assigned to 1) sequential monotherapy, 2) step-up combination therapy, both starting with methotrexate, 3) initial combination therapy, including a tapered high-dose prednisone, or 4) initial combination therapy with methotrexate and infliximab. Treatment was adjusted every 3 months if the Disease Activity Score (DAS) remained >2.4. The McMaster Toronto Arthritis Patient Preference Disability Questionnaire, the Short Form 36 (SF-36), and scores for pain, global health, and disease activity measured on a 100-mm visual analog scale (VAS) were compared between groups at baseline and every 3 months thereafter for 2 years.
After 2 years, all patient-reported outcomes had improved significantly from baseline, irrespective of the treatment strategy. SF-36 subscale scores approached population norms for 3 physical components, and achieved population norms (P > 0.05) for bodily pain and 4 mental components. Improvement in functioning, VAS scores, and physical items of the SF-36 occurred significantly earlier in patients treated with initial combination therapies (all comparisons after 3 months: overall P < 0.001; P < 0.05 for groups 1 and 2 versus groups 3 and 4).
All 4 DAS-driven treatment strategies resulted in substantial improvements in functional ability, quality of life, and self-assessed VAS scores after 2 years. Initial combination therapy led to significantly faster improvement in all patient-reported measures.
[show abstract][hide abstract] ABSTRACT: To compare the clinical and radiological efficacy of initial vs delayed treatment with methotrexate (MTX) and infliximab (IFX) in patients with recent onset rheumatoid arthritis (RA).
In a post hoc analysis of the BeSt study (for Behandel Stratagieen, Dutch for treatment strategies), 117 patients who started initial MTX+IFX were compared with 67 patients who started MTX+IFX treatment after failing (disease activity score (DAS)>2.4; median delay to IFX: 13 months) on > or =3 traditional DMARDs. If the DAS remained >2.4, the protocol dictated IFX dose increases to 6, 7.5 and 10 mg/kg. In case of a DAS < or =2.4 for > or =6 months, IFX was tapered and finally stopped. We aimed to correct for allocation bias using propensity scores. Functional ability was measured by the Health Assessment Questionnaire (HAQ), radiological progression by Sharp/van der Heijde scoring (SHS).
Baseline differences between the initial and delayed groups were no longer significant after propensity score adjustment. At 3 years after baseline, patients treated with initial MTX+IFX experienced more improvement in HAQ over time and were less likely to have SHS progression than patients treated with delayed MTX+IFX (p = 0.034). At 2 years after IFX initiation, more patients in the initial group compared with the delayed group could discontinue IFX after a good response (56% vs 29%, p = 0.008).
The results of this post hoc analysis suggest that using MTX+IFX as initial treatment for patients with recent onset RA is more effective than reserving MTX+IFX for patients who failed on traditional DMARDs, with more HAQ improvement over time, more IFX discontinuation and less progression of joint damage.
Annals of the rheumatic diseases 10/2008; 68(7):1153-8. · 8.11 Impact Factor
[show abstract][hide abstract] ABSTRACT: In RA, conflicting results have been described on the association between genotypes of the complement factor mannose-binding lectin (MBL) and disease susceptibility and severity. This might be due to underpowerment of previous research work and the fact that no confirmation cohorts were used. Therefore a different approach is warranted.
MBL2 gene polymorphisms were determined in two RA cohorts (378 and 261 cases) and 648 controls. Considering MBL polymorphisms, cases and controls were categorized in groups of high, intermediate and low MBL production. The total sample size allows detection of a potential association between RA susceptibility and MBL groups with an odds ratio of 1.37 (alpha < 0.05; 1-beta > 0.8). Disease severity as defined by the need for anti-TNF therapy was also analysed for possible associations with MBL groups.
There was no difference in the frequencies between MBL genotypes of RA cases and controls that are associated with high (cases 54.4%, controls 57.0%), intermediate (cases 28.9%, controls 27.5%) or low (cases 16.7%, controls 15.5%) MBL production. Furthermore, there was no association between MBL groups and disease severity.
MBL genotype groups are not associated with RA disease susceptibility or severity in this large study including a confirmation cohort. Compared with previous smaller studies these results add to more definite conclusions.
[show abstract][hide abstract] ABSTRACT: To investigate the utility of serum COMP level measurements as a predictor of future damage of the weight-bearing (large) joints in RA patients participating in intensive exercise.
Data of the 281 completers of a 2-yr randomized controlled trial (Rheumatoid Arthritis Patients In Training; RAPIT) comparing the effects of usual care physical therapy with high-intensity weight-bearing exercises were analysed. The primary outcome variable was defined as the change in radiological joint damage (Larsen score) of the large joints. Potential predictors of outcome were defined: baseline and change in serum level of COMP after 3 months, baseline radiological damage of the large and small joints, number of months on glucocorticoids, change in disease activity and in physical capacity (aerobic fitness and muscle strength) after 2 yrs, and participation in the exercise group.
In cross-sectional evaluation of baseline data, we found strong association between the high serum COMP level and current damage of the large joints. Serum COMP level at baseline, however, was not associated with an increased rate of radiological joint damage after 2 yrs of follow-up. Furthermore, neither interaction between baseline COMP level and participation in exercises, nor change in COMP level after 3 months of exercising were associated with future damage of the large joints.
Neither baseline serum COMP level nor its individual change after 3 months from start of intensive exercise predict longitudinal progression of damage of the large joints in this population.