Mortality and causes of death across the systemic connective tissue diseases and the primary systemic vasculitides.

Objectives: Studies assessing relative mortality risks across the spectrum of systemic inflammatory rheumatic diseases are largely missing. In this study, we wanted to estimate standard mortality ratios (SMRs) and causes of death in an ethnically homogeneous cohort covering all major CTDs and primary systemic vasculitides (PSVs). Methods: We prospectively followed all incident CTD and PSV cases included in the Norwegian CTD and vasculitis registry (NOSVAR) between 1999 and 2015. Fifteen controls for each patient matched for sex and age were randomly drawn from the Norwegian National Population Registry. Causes of death were obtained from the National Cause of Death Register, death certificates and hospital charts. Results: The cohort included 2140 patients (1534 with CTD, 606 with PSV). During a mean follow-up time of 9 years, 279 of the patients (13%) died, compared with 2864 of 32 086 (9%) controls (P < 0.001). Ten years after diagnosis, the lowest survival was 60% in dcSSc, 73% in anti-synthetase syndrome (ASS) and 75% in lcSSc. In the CTD group, the highest SMRs were observed in dcSSc (SMR 5.8) and ASS (SMR 4.1). In the PSV group, Takayasu arteritis (SMR 2.5) and ANCA-associated vasculitis (SMR 1.5) had the highest SMRs. Major causes of death were cardiovascular disease (CTD 27%, PSV 28%), neoplasms (CTD 25%, PSV 27%), chronic respiratory disease (CTD 20%, PSV10%) and infections (CTD 9%, PSV 16%). Conclusion: We observed premature deaths across the spectrum of CTDs and PSVs, with highest SMRs in dcSSc and ASS. The overall mortality was highest in the CTD group.

Variants in CXCR4 associate with juvenile idiopathic arthritis susceptibility.

BACKGROUND: Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease among children, the etiology of which involves a strong genetic component, but much of the underlying genetic determinants still remain unknown. Our aim was to identify novel genetic variants that predispose to JIA. METHODS: We performed a genome-wide association study (GWAS) and replication in a total of 1166 JIA cases and 9500 unrelated controls of European ancestry. Correlation of SNP genotype and gene expression was investigated. Then we conducted targeted resequencing of a candidate locus, among a subset of 480 cases and 480 controls. SUM test was performed to evaluate the association of the identified rare functional variants. RESULTS: The CXCR4 locus on 2q22.1 was found to be significantly associated with JIA, peaking at SNP rs953387. However, this result is subjected to subpopulation stratification within the subjects of European ancestry. After adjusting for principal components, nominal significant association remained (p < 10(-4)). Because of its interesting known function in immune regulation, we carried out further analyses to assess its relationship with JIA. Expression of CXCR4 was correlated with CXCR4 rs953387 genotypes in lymphoblastoid cell lines (p = 0.014) and T-cells (p = 0.0054). In addition, rare non-synonymous and stop-gain sequence variants in CXCR4, putatively damaging for CXCR4 function, were significantly enriched in JIA cases (p = 0.015). CONCLUSION: Our results suggest the association of CXCR4 variants with JIA, implicating that this gene may be involved in the pathogenesis of autoimmune disease. However, because this locus is subjected to population stratification within the subjects of European ancestry, additional replication is still necessary for this locus to be considered a true risk locus for JIA. This cell-surface chemokine receptor has already been targeted in other diseases and may serve as a tractable therapeutic target for a specific subset of pediatric arthritis patients with additional replication and functional validation of the locus.

Generalized bone loss in early rheumatoid arthritis patients followed for ten years in the biologic treatment era.

BACKGROUND: Osteoporosis is a well-known extra articular manifestation in rheumatoid arthritis (RA). Biologic disease modifying anti rheumatic drugs (DMARDs) has been shown to be superior to synthetic DMARDs to reduce bone destruction including generalized bone loss in RA. Our aim was to study short- and long term changes in hip and spine bone mineral density (BMD) in early RA patients treated during the first decade with available biologic DMARDs. METHODS: RA patients diagnosed at an out-patient clinic between 1999 and 2001 were consecutively enrolled. Demographic, disease and treatment data were collected and BMD was assessed by dual energy X-ray absorptiometry at baseline and after 2, 5 and 10 years. RESULTS: The 92 included RA patients had a baseline mean age (SD) of 50.9 (13.3) years and symptom duration of 12.4 (6.7) months, 62.0% were women and 66.3% were RF positive. In the first 2 years ever use of biologic DMARDs was 18.5%, synthetic DMARDs 91.3% and prednisolone 62.0% whereas the figures for the subsequent 8 years were 62.6%, 89.2% and 51.4%, respectively. The annual rate of BMD loss in the first 2 years and the subsequent 8 years was at femoral neck -1.00% vs. -0.56%, at total hip -0.96% vs. -0.41% and at spine L1-4 -0.42% vs. 0.00%. CONCLUSIONS: Our study adds evidence that aggressive anti-inflammatory treatment including biologic DMARDs reduces the rate of bone loss in RA. Indicating that the burden of osteoporosis is reduced in RA patients treated in clinical practice in the new millennium.

Serum levels of lipoprotein(a) and E-selectin are reduced in rheumatoid arthritis patients treated with methotrexate or methotrexate in combination with TNF-α-inhibitor.

OBJECTIVES: To examine the effect of methotrexate (MTX) with or without tumor necrosis factor alpha (TNF-α)-inhibitors on serum lipoprotein(a) (s-Lp(a)), and to explore a possible relationship between s-Lp(a) and endothelial function (EF) in terms of serum levels of adhesion molecules and reactive hyperaemic index (RHI) in patients with rheumatoid arthritis (RA). METHODS: Serum levels of Lp(a), endothelial adhesion molecules, RHI and inflammatory markers were studied in 64 RA patients, starting with either MTX (n=34) or MTX+TNF-α-inhibitor treatment (n=30) at baseline and after 6 weeks and 6 months. RESULTS: Compared to baseline values, s-Lp(a) was significantly reduced after 6 weeks (p=0.001) and 6 months (p=0.001) in RA patients treated with MTX, and after 6 weeks (p=0.001) in the MTX+TNF-α-inhibitor group. A non-significant reduction was found after 6 months (p=0.102) in the MTX+TNFα-inhibitor group. Serum E-selectin (s-E-selectin) was significantly reduced in both RA treatment groups at both control points. S-Lp(a) correlated positively with s-E-selectin at baseline (p=0.004), and change in s-E-selectin correlated with the change in s-Lp(a) during follow-up (p6weeks= 0.008, p 6months=0.009). No association was found between s-Lp(a) and the other adhesion molecules and RHI. CONCLUSIONS: MTX or MTX combined with a TNFα-inhibitor appears to significantly reduce Lp(a). This finding indicate that s-Lp(a) might be related to systemic inflammation, or that the examined drugs might reduce s-Lp(a) by other mechanisms. Anti-inflammatory treatment might be a novel therapeutic option to decrease s-Lp(a). The associations between s-E-selectin and s-Lp(a) suggest an interaction between these factors, or a common cause.

Antibodies to common infectious agents in coronary artery disease patients with and without rheumatic conditions.

OBJECTIVES: The mechanism linking inflammation to atherosclerosis is unknown. We have previously demonstrated a high occurrence of inflammation in the aortic adventitia of patients with coronary artery disease (CAD), which was more pronounced in patients with inflammatory rheumatic diseases (IRDs), and which might be involved in the pathogenesis of cardiovascular disease. In theory, infections might play a role in the pathogenesis of vascular inflammation or atherosclerosis, or both. This study compared seropositivity and the burden of several common infections in patients with CAD, both with and without IRD, and in healthy controls (HCs). Moreover, we looked for relationships between the examined antibodies and inflammatory infiltrates in the aortic adventitia. METHODS: We examined sera for Chlamydophila pneumoniae, Mycoplasma pneumoniae, Helicobacter pylori, CMV, Streptococcus pyogenes, parvovirus B19, HBV and HCV with commercially available serological tests in 67 patients with IRD, 52 patients without IRD and 30 HCs. RESULTS: We observed neither any statistically significant differences in the examined antibodies between the groups nor a difference in the burden of infection. Except for a protective effect of mycoplasma immunoglobulin A (IgA), we did not find any other associations between the examined antibodies and the occurrence of aortic adventitial mononuclear cell infiltrates. CONCLUSION: Our study does not support the notion that chronic infections or infectious burden contribute to accelerated occurrence of CAD in IRD. Mycoplasma IgA was related to a lower occurrence of aortic adventitial inflammation.

Interferon regulatory factor 5 gene polymorphism confers risk to several rheumatic diseases and correlates with expression of alternative thymic transcripts.

OBJECTIVES: Polymorphisms in genes related to the IFN pathway were investigated for susceptibility to rheumatic diseases and correlation with gene expression in thymus. METHODS: Forty-five polymorphisms were genotyped in Norwegian patients with RA (n = 518), JIA (n = 440), SLE (n = 154) and healthy controls (n = 756). Forty-two thymic samples were used for gene expression analysis. Six hundred and fifty SLE patients and 737 healthy controls from Spain were available for replication. RESULTS: We found a novel association between interferon regulatory factor 5 (IRF5), rs2004640 and JIA, in particular with the polyarthritis RF-negative patients [odds ratio (OR) = 1.60; 95% confidence interval (CI) 1.17, 2.20; P = 0.003]. Also, we confirmed the associations between rs2004640 and SLE (OR = 1.95; 95% CI 1.50, 2.53; P = 3.75 × 10(-7)), which was further strengthened in a meta-analysis (OR = 1.44; 95% CI 1.36, 1.52; P = 2.11 × 10(-37)). Suggestive evidence of association between rs2004640 and RA was found in the Norwegian discovery cohort (OR = 1.19; 95% CI 1.02, 1.40; P = 0.029) and strengthened in a meta-analysis (OR = 1.11; 95% CI 1.05, 1.18; P = 0.00028). Expression levels of exon 1B IRF5 transcripts were dependent on the presence of the rs2004640 T risk allele in thymic tissue, while exon 1A transcript levels correlated with IRF5 promoter CGGGG-indel variants. CONCLUSION: The IFN pathway gene, IRF5, is a common susceptibility factor for several rheumatic and autoimmune diseases, and risk variants are correlated with expression of alternative IRF5 transcripts in thymus implying a regulatory role.

Cardiovascular disease in patients with inflammatory rheumatic disease is associated with up-regulation of markers of inflammation in cardiac microvessels and cardiomyocytes.

OBJECTIVE: Various inflammatory rheumatic diseases (IRDs) are associated with increased mortality due to cardiovascular disease. The aim of this study was to investigate heart biopsy specimens obtained from patients undergoing coronary artery bypass grafting and compare markers of inflammation and endothelial cell activation in the cardiac and skeletal muscle of patients with and those without IRD. METHODS: Paired biopsy specimens of cardiac and skeletal muscle were obtained from 22 consecutive patients with IRD and 8 patients without IRD, all of whom were undergoing coronary artery bypass grafting. The biopsy specimens were evaluated in a blinded manner by conventional microscopy and digital image analysis for cell markers (CD3, CD4, CD8, CD68, CD163, and CD31), HLA (HLA-ABC, HLA-DR, and HLA-DQ), adhesion molecules (intercellular adhesion molecule 1 and vascular cell adhesion molecule 1), and proinflammatory cytokines (interleukin-1alpha, interleukin-1beta, and tumor necrosis factor). RESULTS: Patients with IRD had significantly higher expression of adhesion molecules, proinflammatory cytokines, and all classes of HLA on cardiomyocytes and endothelial cells but no increase on mononuclear cells in the myocardium compared with patients without IRD. Furthermore, cardiac muscle from patients with IRD displayed significantly higher local expression of inflammation and activation of cardiac microvessels compared with skeletal muscle from the same patients. CONCLUSION: Patients with cardiovascular disease had increased expression of adhesion molecules, HLA, and proinflammatory cytokines in heart tissue, indicating local inflammation involving microvessels and cardiomyocytes that could play a role in the pathogenesis of cardiovascular disease. The more pronounced changes in patients with IRD compared with patients without IRD might contribute to the increased risk of cardiovascular disease and premature death in patients with IRD.

Antirheumatic treatment is associated with reduced serum Syndecan-1 in Rheumatoid Arthritis.

The endothelial glycocalyx (EG) is essential for proper function of the endothelium and for vascular integrity, but its role in premature atherogenesis in rheumatoid arthritis (RA) has not been studied yet. EG impairment can play a role in pathogenesis of vascular disease, and one of its characteristics is shedding of syndecan-1 from endothelial cells. Syndecan-1 shedding is mediated by matrix metalloproteinase-9 (MMP-9) and counteracted by tissue inhibitor of metalloproteinases (TIMP)-1. Cardiovascular disease risk in RA is reversible by disease modifying antirheumatic drugs (DMARDs), but the exact modes of action are still unclear. Therefore, we examined effects of DMARDs on syndecan-1, MMP-9 and TIMP-1 in RA patients, and searched for associations between these parameters and inflammatory activity. From the observational PSARA study, we examined 39 patients starting with methotrexate (MTX) monotherapy (in MTX naïve patients, n = 19) or tumor necrosis factor inhibitors (TNFi) in combination with MTX (in MTX non-responders, n = 20) due to active RA. Serum syndecan-1, MMP-9 and TIMP-1 were measured at baseline and after six weeks of treatment. Serum syndecan-1 (p = 0.008) and TIMP-1 (p<0.001) levels decreased after six weeks of anti-rheumatic treatment. Levels of MMP-9 also decreased, but the difference was not statistically significant. The improvement in syndecan-1 levels were independent of changes in inflammatory activity. There was no significant difference in changes in syndecan-1 levels from baseline to 6 weeks between the MTX and TNFi groups, however the change was significant within the MTX group. Six weeks of antirheumatic treatment was associated with reduction in serum levels of syndecan-1, which might reflect reduced syndecan-1 shedding from EG. Thus, it is possible that EG-preserving properties of DMARDs might contribute to their cardioprotective effects. These effects may be at least partly independent of their anti-inflammatory actions. Our findings do not support the notion that syndecan-1 shedding in RA is mediated mainly by increased MMP-9 or decreased TIMP-9 serum concentration.

A CLEC16A variant confers risk for juvenile idiopathic arthritis and anti-cyclic citrullinated peptide antibody negative rheumatoid arthritis.

OBJECTIVE: Variants in CLEC16A have conferred susceptibility to autoimmune diseases in genome-wide association studies. The present work aimed to investigate the locus' involvements in juvenile idiopathic arthritis (JIA) and further explore the association with rheumatoid arthritis (RA), type 1 diabetes (T1D) and Addison's disease (AD) in the Norwegian population. METHODS: Three single nucleotide polymorphisms (SNPs) were genotyped in patients with RA (n=809), JIA (n=509), T1D (n=1211) and AD (n=414) and in healthy controls (n=2149). RESULTS: All diseases were associated with CLEC16A, but with different SNPs. The intron 22 SNP, rs6498169, was associated with RA (p=0.006) and JIA (p=0.016) and the intron 19 SNPs, rs12708716/rs12917716, with T1D (p=1x10-5) and AD (p=2x10-4). The RA association was confined to the anti-cyclic citrullinated peptide antibody (anti-CCP) negative subgroup (p=2x10-4). CONCLUSION: This is the first report of a CLEC16A association with JIA and a split of the RA association according to anti-CCP status. Different causative variants underlie the rheumatic versus the organ specific diseases.

Inflammatory markers in patients with coronary artery disease with and without inflammatory rheumatic disease.

OBJECTIVES: Patients with inflammatory rheumatic diseases (IRDs) have a higher morbidity and mortality from accelerated atherosclerosis than the general population. We hypothesized that patients with the combination of IRD and coronary artery disease (CAD) would have a certain inflammatory phenotype compared with CAD patients without this comorbidity. METHODS: Four groups of patients were included: patients with IRD, referred to coronary artery bypass grafting (CABG) (CAD-IRD, n = 67), patients without IRD, referred to CABG (CAD, n = 52), patients with IRD without CAD (IRD, n = 32) and healthy controls (n = 30). Plasma levels of several inflammatory markers were analysed by enzyme immunoassays. RESULTS: (i) Plasma levels of markers of endothelial cell activation [i.e. vascular cell adhesion molecule-1 (VCAM-1) and von Willebrand factor] and osteoprotegerin (OPG) were significantly increased and plasma levels of CCL21 significantly decreased in CAD-IRD patients as compared with CAD patients without IRD. (ii) Within the CAD-IRD group, acute coronary syndrome was a significant predictor of OPG, suggesting an enhanced inflammatory response during plaque destabilization in CAD-IRD patients. (iii) Plasma levels of VCAM-1, OPG and CCL21, but not lipid parameters, IRD characteristics and several other inflammatory markers (e.g. CRP), were significant predictors of CAD-IRD as opposed to CAD in two logistic regression models. CONCLUSION: Our findings further support a role for inflammation in the accelerated form of atherosclerosis in IRD patients, and suggest that certain inflammatory pathways, such as the enhanced endothelial cell activation and the RANK ligand/RANK/OPG system, may be of particular importance.

Association analysis of the interleukin 17A gene in Caucasian rheumatoid arthritis patients from Norway and New Zealand.

OBJECTIVE: Elevated levels of IL-17A have been detected in the inflamed synovium of RA patients, and murine arthritis models deficient in IL17A have shown reduced inflammation. Our aim was to investigate IL17A as a candidate gene for RA, and to assess correlations between risk variants and disease phenotypes. METHODS: Five single nucleotide polymorphisms (SNPs) were selected to tag the genetic variability of the IL17A region and were genotyped by TaqMan technology on 950 RA cases and 933 random controls from Norway. Associations to progression of radiographic damage and presence of autoantibodies were examined in a 10-yr follow-up cohort of early RA. In addition, 580 RA patients and 504 controls from New Zealand were used as a replication data set. RESULTS: A weak association between RA and the promoter SNP rs2275913 [odds ratio (OR) = 1.17; 95% CI 1.02, 1.34; P = 0.02] was found in the Norwegian population. The association was also evident at the genotype level where it indicated a recessive model. The allelic association was not replicated in the RA cohort from New Zealand (OR = 0.96; 95% CI 0.81, 1.16; P = 0.69). However, combined analysis suggested a weak recessive association (OR = 1.19; 95% CI 1.02, 1.37; P = 0.02). No significant associations were observed with radiographic progression, anti-cyclic citrullinated peptide or IgM-RF. CONCLUSIONS: Modest evidence of an association with IL17A in Norwegian RA patients was observed. Although, our findings were not replicated in an independent RA material from New Zealand, a significant common risk estimate indicated that IL17A warrants further investigation in RA.

Tumor necrosis factor inhibitors are associated with reduced complement activation in spondylarthropathies: An observational study.

BACKGROUND: The complement system is involved in pathogenesis of cardiovascular disease, and might play a role in accelerated atherogenesis in spondylarthropathies (SpA). Hence, we examined complement activation in SpA, and its relationship to antirheumatic treatment, inflammatory and cardiovascular markers. METHODS: From PSARA, a prospective observational study, we examined 51 SpA patients (31 psoriatic arthritis (PsA), and 20 ankylosing spondylitis (AS)), starting tumor necrosis factor (TNF) inhibitor alone (n = 25), combined with methotrexate (MTX) (n = 10), or MTX monotherapy (n = 16). Complement activation was determined by the soluble terminal complement complex (sC5b-9), inflammation by erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), and endothelial function by finger plethysmography (Endopat) at baseline, after 6 weeks and 6 months of treatment. RESULTS: SpA patients had sC5b-9 levels at (PsA) or above (AS) the upper limit of the estimated reference range. Median sC5b-9 levels decreased significantly from baseline to 6 weeks, with no significant difference between the AS and PsA group. Notably, a significant reduction in sC5b-9 was observed after administration of TNF inhibitor ± MTX, whereas no significant changes were observed in patients treated with MTX alone. Between 6 weeks and 6 months, sC5b-9 remained stable across all subgroups. Reduction in sC5b-9 was independently related to decreased ESR and CRP, and to increased high density cholesterol and total cholesterol. Reduction in sC5b-9 from baseline to 6 weeks was associated with improved EF in age and gender adjusted analyses. CONCLUSION: TNF-inhibition, but not MTX monotherapy, led to rapid and sustained reduction of complement activation in SpA. Thus, the observed decrease in cardiovascular morbidity in patients treated with TNF-inhibitors might be partly due to its beneficial effect on complement. TRIAL REGISTRATION: Clinical Trials (NCT00902005), retrospectively registered on the 14th of May 2009.

Lack of association between the chemokine receptor 5 polymorphism CCR5delta32 in rheumatoid arthritis and juvenile idiopathic arthritis.

BACKGROUND: The chemokine receptor CCR5 has been detected at elevated levels on synovial T cells, and a 32 bp deletion in the CCR5 gene leads to a non-functional receptor. A negative association between the CCR5Delta32 and rheumatoid arthritis (RA) has been reported, although with conflicting results. In juvenile idiopathic arthritis (JIA), an association with CCR5 was recently reported. The purpose of this study was to investigate if the CCR5Delta32 polymorphism is associated with RA or JIA in Norwegian cohorts. METHODS: 853 RA patients, 524 JIA patients and 658 controls were genotyped for the CCR5Delta32 polymorphism. RESULTS: The CCR5Delta32 allele frequency was 11.5% in the controls vs. 10.4% in RA patients (OR = 0.90; P = 0.36) and 9.7% in JIA patients (OR = 0.85; P = 0.20). No decreased homozygosity was observed for CCR5Delta32, as previously suggested. CONCLUSION: Our data do not support an association between the CCR5Delta32 allele and Norwegian RA or JIA patients. Combining our results with those from a recently published meta-analysis still provide evidence for a role for CCR5Delta32 in RA, albeit substantially weaker than the effect first reported.

Polymorphisms in the cathepsin L2 (CTSL2) gene show association with type 1 diabetes and early-onset myasthenia gravis.

Type 1 diabetes (T1D) is an autoimmune disease characterized by loss of beta cells in the pancreas. The CTSL2 gene encodes the cysteine protease cathepsin V involved in antigen presentation in human cortical thymic epithelial cells, and involvement of the protease in autoimmunity has been suggested. This study aimed to evaluate CTSL2 as a candidate gene for T1D, and test whether the gene predisposes more generally to autoimmune diseases. Four polymorphisms aiming at tagging the CTSL2 locus were genotyped in 421 T1D families, and subsequently in 861 rheumatoid arthritis patients, 530 juvenile idiopathic arthritis patients, and 559 controls of Norwegian origin. Additionally, DNA from 83 German myasthenia gravis (MG) patients and 244 controls were investigated. A polymorphism, rs16919034, situated downstream of CTSL2 was associated with T1D (60.8%T, p = 0.008; p(c) = 0.03). An association with early-onset MG (45% in cases vs 36.6% in controls; p = 0.03) was observed for another polymorphism (rs4361859) situated upstream of the gene, but within the same linkage disequilibrium block. No association was observed in rheumatoid arthritis or juvenile idiopathic arthritis. Our findings suggest that the CTSL2 gene is associated with T1D and with early-onset MG.

[Rheumatoid arthritis--a risk factor of ischemic heart disease]. / Revmatoid artritt--en risikofaktor for iskemisk hjertesykdom.

BACKGROUND: Traditional treatment of rheumatoid arthritis has been directed against joint damage, not against increased cardiovascular morbidity. METHODS: The article is based on a search in Medline, bibliography of relevant articles, abstracts from congresses of rheumatology, and discussions with experts. RESULTS AND INTERPRETATION: Rheumatoid arthritis is an independent predictor for coronary artery disease, the main cause of premature mortality in rheumatoid patients. Cardiovascular prophylaxis in rheumatoid arthritis should be prioritised. Treatments of traditional cardiovascular risk factors and of inflammation both seem to be important in reducing cardiovascular morbidity. Insight in accelerated atherosclerosis in inflammatory rheumatic diseases may improve our understanding of the pathogenesis of atherosclerosis generally.

[Medical prophylaxis and treatment of steroid induced osteoporosis]. / Medikamentell profylakse og behandling av steroidindusert osteoporose.

BACKGROUND: Glucocorticoid steroids are widely used as antiinflammatory and immunosuppressive medications and are well known to induce osteoporosis. MATERIAL AND METHODS: Randomised clinical trials and Cochrane reports on the use of calcium, vitamin D, bisphosphonates and hormones were reviewed and the results summarised. Additionally, national and some international recommendations were reviewed in order to propose recommendations for prophylaxis and treatment. The literature was identified by Medline searches. RESULTS AND INTERPRETATION: Calcium and vitamin D prevent bone loss in low-to-medium-dose glucocorticoid steroid therapy. Bisphosphonates maintain or modestly increase lumbar and hip bone mass. The fracture risk was not significantly reduced in the spine and the hip. The clinical randomised trials and Cochrane reports conclude that bisphosphonates as well as calcium and vitamin D taken together are effective and the drugs of choice in prevention and treatment.

Rapid Anti-Inflammatory Effects of Gonadotropin-Releasing Hormone Antagonism in Rheumatoid Arthritis Patients with High Gonadotropin Levels in the AGRA Trial.

OBJECTIVES: Gonadotropin-releasing hormone (GnRH) and pituitary gonadotropins, which appear to be proinflammatory, undergo profound secretory changes during events associated with rheumatoid arthritis (RA) onset, flares, or improvement e.g. menopausal transition, postpartum, or pregnancy. Potential anti-inflammatory effects of GnRH-antagonists may be most pronounced in patients with high GnRH and gonadotropin levels. Therefore, we investigated the efficacy and safety of a GnRH-antagonist, cetrorelix, in RA patients with high gonadotropin levels. METHODS: We report intention-to-treat post hoc analyses among patients with high gonadotropin levels (N = 53), i.e. gonadotropin levels>median, from our proof-of-concept, double-blind AGRA-study (N = 99). Patients with active longstanding RA, randomized to subcutaneous cetrorelix (5mg days1-2; 3mg days 3-5) or placebo, were followed through day 15. Only predefined primary and secondary endpoints were analyzed. RESULTS: The primary endpoint, Disease Activity Score of 28-joint counts with C-reactive protein (DAS28-CRP), improved with cetrorelix compared with placebo by day 5 (-1.0 vs. -0.4, P = 0∙010). By day 5, more patients on cetrorelix achieved at least a 20% improvement in the American College of Rheumatology scale (44% vs. 19%, P = 0.049), DAS28-CRP≤3.2 (24% vs. 0%, P = 0.012), and European League against Rheumatism 'Good-responses' (19% vs. 0%, P = 0.026). Tumor necrosis factor-α, interleukin-1ß, interleukin-10, and CRP decreased with cetrorelix (P = 0.045, P = 0.034, P = 0.020 and P = 0.042 respectively) compared with placebo by day 15. Adverse event rates were similar between groups. CONCLUSIONS: GnRH-antagonism produced rapid anti-inflammatory effects in RA patients with high gonadotropin levels. GnRH should be investigated further in RA. TRIAL REGISTRATION: ClinicalTrials.gov NCT00667758.

Epistasis amongst PTPN2 and genes of the vitamin D pathway contributes to risk of juvenile idiopathic arthritis.

Juvenile idiopathic arthritis (JIA) is a leading cause of childhood-onset disability. Although epistasis (gene-gene interaction) is frequently cited as an important component of heritability in complex diseases such as JIA, there is little compelling evidence that demonstrates such interaction. PTPN2, a vitamin D responsive gene, is a confirmed susceptibility gene in JIA, and PTPN2 has been suggested to interact with vitamin D pathway genes in type 1 diabetes. We therefore, tested for evidence of epistasis amongst PTPN2 and the vitamin D pathway genes GC, VDR, CYP24A1, CYP2R1, and DHCR7 in two independent JIA case-control samples (discovery and replication). In the discovery sample (318 cases, 556 controls), we identified evidence in support of epistasis across six gene-gene combinations (e.g., GC rs1155563 and PTPN2 rs2542151, ORint=0.45, p=0.00085). Replication was obtained for three of these combinations. That is, for GC and PTPN2, CYP2R1 and VDR, and VDR and PTPN2, similar epistasis was observed using the same SNPs or correlated proxies in an independent JIA case-control sample (1008 cases, 9287 controls). Using SNP data imputed across a 4 MB region spanning each gene, we obtained highly significant evidence for epistasis amongst all 6 gene-gene combinations identified in the discovery sample (p-values ranging from 5.6×10(-9) to 7.5×10(-7)). This is the first report of epistasis in JIA risk. Epistasis amongst PTPN2 and vitamin D pathway genes was both demonstrated and replicated.

Major histocompatibility complex associations of ankylosing spondylitis are complex and involve further epistasis with ERAP1.

Ankylosing spondylitis (AS) is a common, highly heritable, inflammatory arthritis for which HLA-B*27 is the major genetic risk factor, although its role in the aetiology of AS remains elusive. To better understand the genetic basis of the MHC susceptibility loci, we genotyped 7,264 MHC SNPs in 22,647 AS cases and controls of European descent. We impute SNPs, classical HLA alleles and amino-acid residues within HLA proteins, and tested these for association to AS status. Here we show that in addition to effects due to HLA-B*27 alleles, several other HLA-B alleles also affect susceptibility. After controlling for the associated haplotypes in HLA-B, we observe independent associations with variants in the HLA-A, HLA-DPB1 and HLA-DRB1 loci. We also demonstrate that the ERAP1 SNP rs30187 association is not restricted only to carriers of HLA-B*27 but also found in HLA-B*40:01 carriers independently of HLA-B*27 genotype.