The Value of HLA-DRB1 Shared Epitope, −308 Tumor Necrosis Factor-α Gene Promoter Polymorphism, Rheumatoid Factor, Anti-Citrullinated Peptide Antibodies, and Early Erosions for Predicting Radiological Outcome in Recent-Onset Rheumatoid Arthritis

The Role of Shared Epitope in Rheumatoid Arthritis Prognosis in Relation to Anti-Citrullinated Protein Antibody Positivity

Introduction

Shared epitope (SE) is present in high proportions of anti-citrullinated protein antibody (ACPA) + patients with rheumatoid arthritis (RA) and is associated with poor prognosis. We assessed the role of SE in RA prognosis, in relation to ACPA positivity.

Methods

Patients enrolled in the Brigham and Women’s RA Sequential Study were included. Changes from baseline in disease activity (Disease Activity Score in 28 joints using C-reactive protein [DAS28 (CRP)], Clinical Disease Activity Index [CDAI], Simplified Disease Activity Index [SDAI]) to 1 year were assessed. Baseline characteristics were compared by SE and ACPA status (±; chi-squared, Kruskal-Wallis). Association between number of SE alleles and ACPA status (logistic regression models), relationships between baseline characteristics and changes in disease activity (adjusted linear regression model), and effect of ACPA on the association between SE and changes in disease activity (mediation analysis) were studied.

Results

Nine hundred twenty-six patients were included. SE + versus SE − patients had significantly longer disease duration and higher disease activity scores and were more likely to have erosive disease, have higher comorbidity burden, and be RF + (all p < 0.05). Among patients with one or two SE alleles (vs. 0), odds of being ACPA + were 1.97 (p = 0.0003) and 3.82 (p < 0.0001), respectively. SE + versus SE − patients had worse disease activity scores as indicated by mean increases in DAS28 (CRP) of 0.22, CDAI of 2.07, and SDAI of 2.43 over 1 year (all p < 0.05). Direct effect of SE + accounted for 76.4–80.1% of total effect in disease activity increases.

Conclusions

SE is strongly associated with ACPA positivity and higher disease activity in patients with RA. SE was associated with greater increases in disease activity over 1 year, which was partially mediated by the presence of ACPA.

Trial Registration

ClinicalTrials.gov identifier: NCT01793103; registration date: February 15, 2013, retrospectively registered.

Patients with rheumatoid arthritis (RA) experience inflamed and damaged joints. RA is an autoimmune disease where proteins called autoantibodies in the blood of patients with RA target the patient’s own joint tissue and organs by mistake. This causes inflammation. Patients with certain autoantibodies, such as anti-citrullinated protein antibodies (ACPAs), may experience worse symptoms. There are certain genetic risk factors that may mean a person is more likely to develop RA. One example of a genetic risk factor is having the shared epitope (SE).

Our study looked at almost 1000 patients with RA in the general population. It explored the impact of having SE and ACPAs on changes in RA disease activity. Patients with SE had RA for a longer time, had more severe disease, and were more likely to have other diseases compared with patients without SE. Patients with SE were also more likely to have ACPAs. Over the course of one year, patients with SE had larger increases in RA disease activity than those patients without SE, even though they were taking the same treatments. These results suggest that patients with the genetic risk factor, SE often have RA that is harder to treat. Doctors should take this into account when selecting treatment for RA.

Tumour necrosis factor gene polymorphisms in Egyptian patients with rheumatoid arthritis and their relation to disease activity and severity

Aim of the study

The present case control study was conducted to assess the association of LTA 252 A>G, TNF-α 308 G>A, and TNF-α 1031 T>C gene polymorphisms with rheumatoid arthritis (RA), and their involvement in disease activity and severity.

Material and methods

A total of 70 Egyptians, including 35 RA patients and 35 healthy control individuals, were included in the study. The RA patients comprised 34 females and one male. Cases with RA were diagnosed by a rheumatologist and fulfilled the 2010 ACR/EULAR criteria. Modified disease activity score (DAS28) was used to assess disease activity. Van Der Heijde-modified Sharp score (vdHSS) was used to assess radiological changes for assessment of disease severity. PCR-RFLP was used to detect the association of LTA 252 A>G, TNF-α 308 G>A, and TNF-α 1031 T>C gene polymorphisms with RA.

Results

TNF-α 308 G allele and TNF-α 308 GG genotype were significantly higher in RA patients compared to healthy control subjects (p = 0.04 and p = 0.001, respectively). TNF-α 308 G allele and GG genotype were significantly higher in the RA non-remission group compared to the remission group (p = 0.008, p < 0.001). Patients with the TNF-α 308 AG genotype had higher mean of Sharp score compared to the patients with the GG and AA genotypes (p = 0.007). There was no significant association between LTA 252 A>G and TNF-α 1031 T>C gene polymorphisms and RA.

Conclusions

Our results suggest that TNF-α 308 G/A gene polymorphism is genetically associated with RA and involved in disease activity and severity in Egyptian patients.

Predictors of remission, erosive disease and radiographic progression in a Colombian cohort of early onset rheumatoid arthritis: a 3-year follow-up study

The objective of the study is to find predictors of remission, radiographic progression (RP), and erosive disease in a cohort of patients with early onset rheumatoid arthritis (EORA) that followed a therapeutic protocol aiming at remission, in a real world tight-control setting. EORA patients were enrolled in a 3-year follow-up study. Clinical, biological, immunogenetic, and radiographical data were analyzed. Radiographs were scored according to Sharp-van der Heijde (SvdH) method. RP was defined by an increase of 3 units in 36 months. Remission was defined as DAS28 <2.6. A stepwise multiple logistic regression model was used to identify independent predictors of the three target outcomes. One hundred twenty-nine patients were included. Baseline disease activity was high. Significant overall improvement was observed, but only 33.3 % achieved remission. At 36 month, 50.4 % (65) of patients showed erosions. RP was observed in 62.7 % (81) of cases. Statistical analysis showed that baseline SvdH score was the only predictive factor associated with the three outcomes evaluated. Lower HAQ-DI and absence of autoantibodies were predictive of remission. Higher levels of ESR and presence of erosions at entry were predictive of RP. Independent baseline predictors of incident erosive disease were anti-CCP and RF positivity, symptom duration at baseline >3 months, and presence of HLA-DRB1 shared epitope. Radiographic damage at baseline was the main predictor of outcomes. Autoantibodies, HAQ and ESR at baseline, symptom duration before diagnosis, and HLA-DRB1 status had influence on clinical course and development of structural joint damage in Colombian RA patients.

Predictive value of autoantibodies from anti-CCP2, anti-MCV and anti-human citrullinated fibrinogen tests, in early rheumatoid arthritis patients with rapid radiographic progression at 1 year: results from the ESPOIR cohort

Objectives

We compared the ability of antibodies against cyclic citrullinated peptides (anti-CCP2), against mutated citrullinated vimentin (anti-MCV) and against citrullinated fibrinogen (AhFibA) to predict 1 year rapid radiographic progression (RRP; total Sharp score variation ≥5 points), in early rheumatoid arthritis (RA).

Methods

We analysed 566 patients from the ESPOIR cohort with early RA fulfilling the 2010 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) criteria at year 1. We assayed the 3 anticitrullinated peptide antibodies (ACPA) tests on baseline sera. We compared the performance of these 3 ACPA tests to predict first-year RRP, by comparing areas under the receiver operating characteristic curves (ROCs). We assessed the 1 year RRP risk by ACPA titres. We used a logistic multivariate regression to analyse RRP risk in terms either of ACPA positivity or titre: high (>3 times the N cut-off) and low (1 to 3N).

Results

145 patients displayed RRP. Areas under the ROCs were similar (0.60) for the 3 tests. High ACPA titres were associated with 1 year RRP, whatever the test was, and with similar ORs. Low+ anti-MCV titres were not associated with 1-year RRP, whereas low+ anti-CCP2 titres (p=0.0226) and low+ AhFibA titres (p=0.0332) were significantly associated. In multivariate analysis, 1 year RRP was associated with anti-CCP2 positivity (p<0.0001), AhFibA positivity (p<0.0001) and high anti-MCV titres (p<0.0001).

Conclusions

Anti-CCP2 antibodies and AhFibA were predictive of 1 year RRP in early RA whatever their titre was, whereas only high anti-MCV antibody titres were predictive, potentially making them more discriminant to predict 1 year RRP risk.

The role of genetic variants in CRP in radiographic severity in African Americans with early and established rheumatoid arthritis

This study investigates the association of CRP (C-reactive protein) single-nucleotide polymorphisms (SNPs) with plasma CRP levels and radiographic severity in African Americans with early and established rheumatoid arthritis (RA). Using a cross-sectional case-only design, CRP SNPs were genotyped in two independent sets of African Americans with RA: Consortium for the Longitudinal Evaluation of African Americans with RA (CLEAR 1) and CLEAR 2. Radiographic data and CRP measurements were available for 294 individuals from CLEAR 1 (median (interquartile range (IQR) 25-75) disease duration of 1 (0.6-1.6) year) and in 407 persons from CLEAR 2 (median (IQR 25-75) disease duration of 8.9 (3.5-17.7) years). In CLEAR 1, in adjusted models, the minor allele of rs2808630 was associated with total radiographic score (incident rate ratio 0.37 (95% confidence interval (CI) 0.19-0.74), P-value=0.0051). In CLEAR 2, the minor allele of rs3093062 was associated with increased plasma CRP levels (P-value=0.002). For each rs3093062 minor allele, the plasma CRP increased by 1.51 (95% CI 1.15-1.95) mg dl(-1) when all the other covariates remained constant. These findings have important implications for assessment of the risk of joint damage in African Americans with RA.

The role of citrullinated protein antibodies in predicting erosive disease in rheumatoid arthritis: a systematic literature review and meta-analysis

Background. Autoantibodies to citrullinated peptides have been shown to be valuable in the diagnosis of rheumatoid arthritis (RA). The expanding repertoire of antibodies to citrullinated peptide antigens (ACPA) has been a topic of great interest in recent reviews and research studies, as has the ability of these autoantibodies to predict disease outcome. Objectives. The aim of this review was to provide an update on the relevance of ACPA as prognostic markers in RA. The ability to identify patients predisposed to an aggressive outcome at the time of initial diagnosis greatly facilitates the selection of appropriate and cost-effective treatment. Methods. A systematic review of the literature was carried out. Studies from 1967 up to June 2014 with data on prognostic value of ACPA were included. Quality assessment was done by using the modified Hayden list for prognostic studies. Meta-analysis was performed using BioStat software. Results. The results of 25 studies were selected for the final review. A total of 6421 patients with RA were included, mainly in inception cohorts, with follow-up duration ranging from one year to ten years. All studies carried prognostic data on all available isotypes of anticyclic citrullinated protein (CCP), while four had data on antimutated citrullinated vimentin (MCV). There was a single relevant study each on anticitrullinated enolase peptide 1 (CEP1) and antichimaeric fibrin/filaggrin citrullinated peptide 1 (CFFCP1). All studies showed ACPA to be strong predictors of joint erosions in RA. Other factors, particularly baseline erosions, showed an additive effect. Anti-MCV appeared to be a marker of a more aggressive form of disease. Ten studies had data on which a meta-analysis could be performed. This gave an overall odds ratio of 4.85 for ACPA (anti-CCP/MCV) positivity being predictive for the development of joint erosions. Two studies with data on anti-CEP1 and anti-CFFCP1 also showed this positive predictive role of ACPA for joint erosions. Conclusions. ACPA are strong predictors of severity in RA. Their use should be part of routine rheumatology practice.

Characterization of cumulative joint damage patterns in patients with rheumatoid arthritis: a clinical, serological, and gene polymorphism perspective

OBJECTIVE

To characterize cumulative joint damage (CJD) patterns in rheumatoid arthritis (RA) and determine their associations with demographic/clinical features and HLA-DRB1 gene polymorphism.

METHODS

Hand and foot radiographs were obtained from 404 patients with RA. CJD patterns were determined by 3 derivations from Sharp/van der Heijde scores, obtained by the mathematical division of scores for hands/feet (Sharp-h/f score), fingers/wrists (Sharp-f/w score), and erosion/space narrowing (Sharp-e/sn score), respectively. DNA and serum were obtained for determination of HLA-DRB1 polymorphism, rheumatoid factor (RF), and anticitrullinated protein antibodies (ACPA).

RESULTS

Patients with wrist-dominant CJD pattern were more likely to have severe RA than those with finger-dominant pattern (68.4% vs 46.0%; p = 0.036) as were those with foot-dominant vs hand-dominant CJD pattern (76.5% vs 56.4%; p = 0.044). HLA-DRB1 shared epitope (SE) alleles were associated with erosion-dominant CJD pattern (p = 0.021). Patients with erosion-dominant CJD pattern had higher levels of RF and ACPA than those with space-narrowing-dominant CJD pattern (median RF 71.35 U/ml vs 22.05 U/ml, respectively; p = 0.003; median ACPA 187.9 U/ml vs 143.2 U/ml, respectively; p < 0.001). The majority of triple-positive patients (SE+, RF+, ACPA+) had erosion-dominant CJD pattern (62.3%) while the majority of triple-negative patients (SE-, FR-, ACPA-) had space narrowing-dominant CJD pattern (75%; p = 0.017). ACPA was associated with HLA-DRB1 SE alleles (p < 0.05). Patients with foot-dominant CJD pattern were taller than those with hand-dominant CJD pattern (p = 0.002); those with erosion-dominant CJD pattern had higher weight and body mass index than those with space narrowing-dominant CJD pattern (p = 0.014, p = 0.001).

CONCLUSION

CJD patterns were associated with disease severity, HLA-DRB1 SE status, presence and titer of ACPA and RF, and morphometric features.

The association between TNFα gene polymorphisms and susceptibility to rheumatoid arthritis in an ethnic Kashmiri population: relationship with disease activity and severity markers

AIM

The aim of our study was to determine the genetic associations between polymorphisms of the TNFα gene (-308G/A and -238G/A) with disease susceptibility and severity in patients with rheumatoid arthritis (RA) in an ethnic Kashmiri population.

METHODS

Allele and genotype frequencies of TNFα-308G/A and TNFα-238G/A polymorphisms were compared between 150 RA patients and 200 healthy controls by using polymerase chain reaction - restriction fragment length polymorphism method. Demographic, clinical and serological data were prospectively evaluated. Disease activity score (DAS28) was also assessed.

RESULTS

We did not find any significant association between TNFα-308G/A and TNFα-238G/A polymorphism and RA risk (P > 0.05), but TNFα-308GG genotype was associated significantly with rheumatoid factor seropositivity (P < 0.01) and TNFα-238GA genotype was associated with swollen joint count < 5 (P = 0.04) as well as with less severe disease activity as measured by DAS28 score (P = 0.02).

CONCLUSION

Our findings suggest the possible roles of TNFα-308GG and TNFα-238GA as important determinants for the development of certain manifestations and disease severity in RA in ethnic Kashmiri population.

Meta-analysis identified the TNFA -308G > A promoter polymorphism as a risk factor for disease severity in patients with rheumatoid arthritis

Introduction

The goal of this study is to investigate whether the -308G > A promoter polymorphism in the tumor necrosis factor alpha (TNFA) gene is associated with disease severity and radiologic joint damage in a large cohort of patients with rheumatoid arthritis (RA).

Methods

A long-term observational early RA inception cohort (n = 208) with detailed information about disease activity and radiologic damage after 3, 6 and 9 years of disease was genotyped for the TNFA -308G > A promoter polymorphism (rs1800629). A longitudinal regression analysis was performed to assess the effect of genotype on RA disease severity and joint damage. Subsequently, a meta-analysis, including all publically available data, was performed to further test the association between joint erosions and the TNFA polymorphism. To learn more about the mechanism behind the effect of the polymorphism, RNA isolated from peripheral blood from RA patients (n = 66) was used for TNFA gene expression analysis by quantitative PCR.

Results

Longitudinal regression analysis with correction for gender and disease activity showed a significant difference in total joint damage between GG and GA+AA genotype groups (P = 0.002), which was stable over time. The meta-analysis, which included 2,053 patients, confirmed an association of the genetic variant with the development of erosions (odds ratio 0.78, 95% CI 0.62, 0.98). No significant differences in TNFA gene expression were observed for the different genotypes, confirming earlier findings in healthy individuals.

Conclusions

Our data confirm that the TNFA -308G > A promoter polymorphism is associated with joint damage in patients with RA. This is not mediated by differences in TNFA gene expression between genotypes.

Anticitrullinated Protein Antibody, But Not Its Titer, Is a Predictor of Radiographic Progression and Disease Activity in Rheumatoid Arthritis

Objective.

To study the contribution of anticitrullinated protein antibody (ACPA), and especially of its titer, to radiographic progression and disease activity in rheumatoid arthritis (RA).

Methods.

Patients with RA (n = 396) who attended a Japanese clinic within 2 years after disease onset were divided into the following groups according to second-generation (ACPA-2) ACPA titer on their first visit: negative (0–4.4 U/ml; n = 115), low-positive (4.5–121 U/ml; n = 141), and high-positive (> 121 U/ml; n = 140). The ACPA-2-positive groups were further subdivided into lowest (4.5–32 U/ml), low (33–121 U/ml), high (122–277 U/ml), and highest (> 278 U/ml) quartiles. All patients were treated with disease-modifying antirheumatic drugs (DMARD) including methotrexate, but not biologics. Subsequent radiographic progression and disease activity for 2 years were prospectively evaluated using the van der Heijde-modified Sharp score (SHS) and 28-joint Disease Activity Score (DAS28).

Results.

After treatment with DMARD, the disease activity (including number of swollen joints, number of tender joints, duration of morning stiffness, DAS28-erythrocyte sedimentation rate, and DAS28-C-reactive protein) was significantly decreased in all patient groups. Disease activity and radiographic progression as revealed by the change in SHS remained relatively higher in the ACPA-2 low- and high-positive groups as compared with the ACPA-2-negative group. The relationship between the titer of ACPA-2 at baseline and subsequent radiographic progression was not exactly linear, and the extent of disease activity or radiographic progression was similar between ACPA-2 low- and high-positive groups and also between ACPA-2 lowest- and highest-positive quartile groups. The results were demonstrable in cumulative SHS probability plots, and also repeatable in seronegative patients, which indicated that the titer of ACPA-2 is not a predictor of disease activity or radiographic progression in RA, and ACPA-2-negative patients, especially those with < 3 U/ml, showed minimal radiographic progression.

Conclusion.

Presence of ACPA-2, but not its titer, at baseline is a predictor of radiographic progression or disease activity, where radiographic progression is minimal in ACPA-2-negative patients.

Radiographic estimation in seropositive and seronegative rheumatoid arthritis

Long since it have been suggested that a subpopulation of patients with rheumatoid arthritis, diagnosed with negative rheumatoid factor tests, represents a clinical entity quite distinct from that of seropositive rheumatoid arthritis (RA). Our aim was to establish a scientific comparative analysis between seronegative and seropositive rheumatoid arthritis, regarding some radiological and clinical parameters, applied for the first time on patients from Kosovo. Two hundred fifty patients with rheumatoid arthritis according to the American College of Rheumatology criteria were retrospectively studied by analysis the radiographic damage and clinical parameters of the disease, using a data base. All examinees were between 25-60 years of age (Xb=49.96, SD=10.37) with disease duration between 1-27 years (Xb = 6.41, SD=6.47). All patients underwent a standardised evaluation radiographs. Baseline standardised poster anterior radiographs of hands and feet and radiographs of other joints, depending on indications, were assessed. Erythrocyte sedimentation rate values correlated with the radiological damages and statistical difference was found for seronegative subset (r=0.24, p<0.01). Longer duration of the disease resulted in the increase of radiological changes in both subsets (r=0.66, p<0.01) seronegative, (r=0.49, p<0.01) seropositive. Anatomic changes of IInd and IIIrd level were nearly equally distributed in both subsets, 76 (60.8%) seronegative, 75 (60%) seropositive. Radiological damages are nearly equal in both subsets, elevate in relation to the duration of the disease and correlate with ESR values. Regarding the sero-status, differences within sex, with some exceptions, are not relevant. Although there are some definite quantitative and qualitative differences regarding sero-status, obviously there is a great deal of overlap between the two groups.

Genetic risk score predicting risk of rheumatoid arthritis phenotypes and age of symptom onset

Background

Cumulative genetic profiles can help identify individuals at high-risk for developing RA. We examined the impact of 39 validated genetic risk alleles on the risk of RA phenotypes characterized by serologic and erosive status.

Methods/Principal Findings

We evaluated single nucleotide polymorphisms at 31 validated RA risk loci and 8 Human Leukocyte Antigen alleles among 542 Caucasian RA cases and 551 Caucasian controls from Nurses' Health Study and Nurses' Health Study II. We created a weighted genetic risk score (GRS) and evaluated it as 7 ordinal groups using logistic regression (adjusting for age and smoking) to assess the relationship between GRS group and odds of developing seronegative (RF− and CCP−), seropositive (RF+ or CCP+), erosive, and seropositive, erosive RA phenotypes. In separate case only analyses, we assessed the relationships between GRS and age of symptom onset.

In 542 RA cases, 317 (58%) were seropositive, 163 (30%) had erosions and 105 (19%) were seropositive with erosions. Comparing the highest GRS risk group to the median group, we found an OR of 1.2 (95% CI = 0.8–2.1) for seronegative RA, 3.0 (95% CI = 1.9–4.7) for seropositive RA, 3.2 (95% CI = 1.8–5.6) for erosive RA, and 7.6 (95% CI = 3.6–16.3) for seropositive, erosive RA. No significant relationship was seen between GRS and age of onset.

Conclusions/Significance

Results suggest that seronegative and seropositive/erosive RA have different genetic architecture and support the importance of considering RA phenotypes in RA genetic studies.

The contribution of four immunogenetic markers for predicting persistent activity in patients with recent-onset rheumatoid arthritis or undifferentiated arthritis

We assessed the contribution of four baseline markers-HLA-DRB1 shared epitope (SE), -308 tumor necrosis factor α gene promoter polymorphism, rheumatoid factor, and anticitrullinated peptide antibodies-for predicting persistent activity (DAS28 score ≥2.6) after one year of followup in a cohort of 201 patients with recent-onset rheumatoid arthritis (RA) or undifferentiated arthritis (UA) aged 16 years or older who had a 4-week to 12-month history of swelling of at least two joints. Patients had not been previously treated with corticosteroids or disease-modifying antirheumatic drugs (DMARD). In the best logistic regression model, only two variables were retained: SE positivity and number of DMARD administered (area under the curve = 76.4%; 95% CI: 69.2%, 84.4%; P < 0.001). The best linear regression model also included these two variables, explaining only 22.5% of the variability of DAS28 score. In this study, given an equal number of DMARD administered, the probability of persistent activity in patients with recent-onset RA or UA was significantly influenced by SE presence.

TNFA -308 (rs1800629) polymorphism is associated with a higher risk of cardiovascular disease in patients with rheumatoid arthritis

OBJECTIVE

To assess the influence of the TNFA rs1800629 (G > A) polymorphism in the risk of cardiovascular (CV) disease and subclinical atherosclerosis in patients with rheumatoid arthritis (RA).

METHODS

587 patients fulfilling the 1987 American College of Rheumatology classification criteria for RA were studied. Patients were genotyped for the TNFA rs1800629 polymorphism using predesigned TaqMan single nucleotide polymorphism genotyping assay. Also, HLA-DRB1 genotyping was performed using molecular based methods. Carotid artery intima-media thickness, flow-mediated endothelium-dependent and endothelium independent vasodilatation, used as surrogate markers of subclinical atherosclerosis, were measured in a subgroup of patients.

RESULTS

We observed a higher frequency of carriers of the minor allele A among the patients with CV disease (with 37.6% vs. without 27.9%, p = 0.06, OR 1.56 [95% confidence interval-CI 0.95-2.54]). Carriers of the minor allele A exhibited a higher risk of CV events after adjustment for demographic and traditional CV risk factors (p = 0.023, HR 1.72 [95% CI 1.076-2.74]). Also, a significant interaction between this polymorphism and the presence of the rheumatoid shared epitope (SE) was observed (p = 0.024). Due to this, the association between carriers of the minor allele A and CV disease was only present in carriers of the SE, even after adjustment (p = 0.001, HR 2.43 [95% CI 1.41-4.19]). No significant association between the TNFA variant and the surrogate markers of subclinical atherosclerosis was observed.

CONCLUSION

Our results show that TNFA rs1800629 gene polymorphism is associated with predisposition to CV complications in patients with RA. This predisposition is restricted to individuals carrying the rheumatoid SE.

IL10 GGC Haplotype Is Positively and HLA-DQA1*05-DQB1*02 Is Negatively Associated with Radiographic Progression in Undifferentiated Arthritis

Objective.

In rheumatoid arthritis (RA), many genetic markers, such as the shared-epitope (SE) alleles, are described in association with radiographic progression, but limited data are available on undifferentiated arthritis (UA). We investigated whether single-nucleotide polymorphisms (SNP) and haplotypes in immune response genes and HLA class II alleles are associated with radiographic progression in patients with early UA.

Methods.

Progression of radiographic damage was determined in white Dutch patients with early UA after 2 years of followup. Severe progression was defined as an increase in Sharp/van der Heijde Score ≥ 5 points after 2 years of followup. The remainder was classified as mild. These SNP were genotyped by Taqman technology: tumor necrosis factor (TNF) −1031, −863, −857, −308, −238; lymphotoxin-α (LTA) +368, +252; interleukin 10 (IL10) −2849, −1082, −819; IL1A −889, IL1B −31, +3953; and IL1RN +2018. Carriage of SE alleles and HLA-DQA1*05-DQB1*02 haplotype was established. These markers were analyzed in relation to radiographic progression.

Results.

Forty-eight out of 151 patients with early UA had severe radiographic progression. Severe radiographic progression was associated with an increased carrier frequency of SE alleles (OR 5.12, 95% CI 2.0–13.1, p < 0.001) and IL10 GGC haplotype (OR 2.8, 95% CI 1.4–5.8, p = 0.003). Mild radiographic progression was associated with the HLA-DQA1*05-DQB1*02 haplotype (OR 0.3, 95% CI, 0.1–0.8, p = 0.013) and with allele TNF −308A (OR 0.4, 95% CI, 0.2–0.9, p = 0.02).

Conclusion.

The SE and the IL10 GGC haplotype are associated with severe progression of radiographic damage, in contrast to the DQA1*05-DQB1*02 haplotype and the TNF −308A allele, which are associated with mild radiographic progression in early UA.

Update on the genetic risk factors for rheumatoid arthritis

Rheumatoid arthritis (RA) is a complex disease, meaning that multiple genetic variants, environmental factors and random events interact to trigger pathological pathways. Although many of these etiological factors have not yet been identified, recent groundbreaking advances have expanded our knowledge about the genetic factors that contribute to RA. Here, we review the most recent findings on the genetic risk factors for RA. First, we give an overview of the genetics of RA and briefly describe the susceptibility loci discovered prior to the availability of genome-wide association studies (GWAS). Second, we focus on the newly discovered RA loci that have arisen from GWAS in populations of European ancestry. Through these studies, the number of established RA susceptibility loci has now grown to 13. Third, we discuss several important issues emerging from GWAS, such as ethnic heterogeneity and shared autoimmunity risk loci. Finally, we discuss what still needs to be accomplished before a more complete picture of the genetic risk to RA can be attained.