Saedis Saevarsdottir

Patients with early rheumatoid arthritis who smoke are less likely to respond to treatment with methotrexate and tumor necrosis factor inhibitors: Observations from the Epidemiological Investigation of Rheumatoid Arthritis and the Swedish Rheumatology Register cohorts

OBJECTIVE To determine whether cigarette smoking influences the response to treatment in patients with early rheumatoid arthritis (RA). METHODS We retrieved clinical information about patients entering the Epidemiological Investigation of Rheumatoid Arthritis (EIRA) early RA cohort from 1996 to 2006 (n=1,998) who were also in the Swedish Rheumatology Register (until 2007). Overall, 1,430 of the 1,621 registered patients were followed up from the time of inclusion in the EIRA cohort. Of these, 873 started methotrexate (MTX) monotherapy at inclusion, and 535 later started treatment with a tumor necrosis factor (TNF) inhibitor as the first biologic agent. The primary outcome was a good response according to the European League Against Rheumatism criteria at the 3-month visit. The influence of cigarette smoking (current or past) on the response to therapy was evaluated by logistic regression, with never smokers as the referent group. RESULTS Compared with never smokers, current smokers were less likely to achieve a good response at 3 months following the start of MTX (27% versus 36%; P=0.05) and at 3 months following the start of TNF inhibitors (29% versus 43%; P=0.03). In multivariate analyses in which clinical, serologic, and genetic factors were considered, the inverse associations between current smoking and good response remained (adjusted odds ratio [OR] for MTX response 0.60 [95% CI 0.39-0.94]; adjusted OR for TNF inhibitor response 0.52 [95% CI 0.29-0.96]). The lower likelihood of a good response remained at later followup visits. Evaluating remission or joint counts yielded similar findings. Past smoking did not affect the chance of response to MTX or TNF inhibitors. Evaluating the overall cohort, which reflects all treatments used, current smoking was similarly associated with a lower chance of a good response (adjusted ORs for the 3-month, 6-month, 1-year, and 5-year visits 0.61, 0.65, 0.78, 0.66, and 0.61, respectively). CONCLUSION Among patients with early RA, current cigarette smokers are less likely to respond to MTX and TNF inhibitors.

Low Serum Mannose-Binding Lectin Level Increases the Risk of Death due to Pneumococcal Infection

Abstract Background. Previous studies have shown associations between low mannose-binding lectin (MBL) level or variant MBL2 genotype and sepsis susceptibility. However, MBL deficiency has not been rigorously defined, and associations with sepsis outcomes have not been subjected to multivariable analysis. Methods. We reanalyzed MBL results in a large cohort with use of individual data from 4 studies involving a total of 1642 healthy control subjects and systematically defined a reliable deficiency cutoff. Subsequently, data were reassessed to extend previous MBL and sepsis associations, with adjustment for known outcome predictors. We reanalyzed individual data from 675 patients from 5 adult studies and 1 pediatric study of MBL and severe bacterial infection. Results. XA/O and O/O MBL2 genotypes had the lowest median MBL concentrations. Receiver operating characteristic analysis revealed that an MBL cutoff value of 0.5 ≪g/mL was a reliable predictor of low-producing MBL2 genotypes (sensitivity, 82%; specificity, 82%; negative predictive value, 98%). MBL deficiency was associated with increased likelihood of death among patients with severe bacterial infection (odds ratio, 2.11; 95% confidence interval, 1.30–3.43). In intensive care unit–based studies, there was a trend toward increased risk of death among MBL-deficient patients (odds ratio, 1.58; 95% confidence interval, 0.90–2.77) after adjustment for Acute Physiology and Chronic Health Enquiry II score. The risk of death was increased among MBL-deficient patients with Streptococcus pneumoniae infection (odds ratio, 5.62; 95% confidence interval, 1.27–24.92) after adjustment for bacteremia, comorbidities, and age. Conclusions. We defined a serum level for MBL deficiency that can be used with confidence in future studies of MBL disease associations. The risk of death was increased among MBL-deficient patients with severe pneumococcal infection, highlighting the pathogenic significance of this innate immune defence protein.

Predictors of response to methotrexate in early DMARD naïve rheumatoid arthritis: results from the initial open-label phase of the SWEFOT trial

Objective To identify predictors of response to methotrexate (MTX) in early rheumatoid arthritis (RA). Methods In the SWEFOT trial, patients with RA with symptom duration <1 year started MTX monotherapy (20 mg/weekly) and 405/487 continued until the 3–4- month visit. The primary outcome measure was the DAS28-based European League against Rheumatism (EULAR) response criteria. Multivariate logistic regression was used to study the association between response and the following baseline characteristics: gender, age, symptom duration, cigarette smoking habits, autoantibody status, Health Assessment Questionnaire (HAQ) score, concurrent prednisolone and treatment with non-steroidal anti-inflammatory drugs. Secondary response and remission measures were the American College of Rheumatology and the Simple Disease Activity Index and Clinical Disease Activity Index (SDAI/CDAI)-derived criteria. Results After 3–4 months of MTX treatment, the frequency of EULAR good/moderate/no response was 34%/41%/25%, respectively. Parameters associated with a decreased likelihood of EULAR response were female gender (adjusted OR (adj OR) 0.50, 95% CI 0.31 to 0.81), symptom duration (adj OR per month increase 0.93, 95% CI 0.88 to 0.99), current smoking (adj OR 0.35, 95% CI 0.20 to 0.63) and higher HAQ (adj OR 0.56, 95% CI 0.40 to 0.80). Parameters associated with an increased likelihood of EULAR response were higher age (adj OR per 10-year increase 1.30, 95% CI 1.11 to 1.51) and prednisolone treatment (adj OR 2.84, 95% CI 1.43 to 5.63). The findings were similar when patients on prednisolone were excluded and other response criteria tested, although current smoking was the only significant predictor using all response criteria, while HAQ was the only significant predictor of all the remission criteria used. A matrix showed up to ninefold differences between subgroups stratified by the main predictors. Conclusion Current smoking, female sex, longer symptom duration and younger age predict a worse response to MTX in patients with new-onset RA. TrialRegNo NCT00764725

Rheumatoid Arthritis Risk Allele PTPRC Is Also Associated With Response to Anti-Tumor Necrosis Factor alpha Therapy

OBJECTIVE Anti-tumor necrosis factor alpha (anti-TNF) therapy is a mainstay of treatment in rheumatoid arthritis (RA). The aim of the present study was to test established RA genetic risk factors to determine whether the same alleles also influence the response to anti-TNF therapy. METHODS A total of 1,283 RA patients receiving etanercept, infliximab, or adalimumab therapy were studied from among an international collaborative consortium of 9 different RA cohorts. The primary end point compared RA patients with a good treatment response according to the European League Against Rheumatism (EULAR) response criteria (n = 505) with RA patients considered to be nonresponders (n = 316). The secondary end point was the change from baseline in the level of disease activity according to the Disease Activity Score in 28 joints (triangle upDAS28). Clinical factors such as age, sex, and concomitant medications were tested as possible correlates of treatment response. Thirty-one single-nucleotide polymorphisms (SNPs) associated with the risk of RA were genotyped and tested for any association with treatment response, using univariate and multivariate logistic regression models. RESULTS Of the 31 RA-associated risk alleles, a SNP at the PTPRC (also known as CD45) gene locus (rs10919563) was associated with the primary end point, a EULAR good response versus no response (odds ratio [OR] 0.55, P = 0.0001 in the multivariate model). Similar results were obtained using the secondary end point, the triangle upDAS28 (P = 0.0002). There was suggestive evidence of a stronger association in autoantibody-positive patients with RA (OR 0.55, 95% confidence interval [95% CI] 0.39-0.76) as compared with autoantibody-negative patients (OR 0.90, 95% CI 0.41-1.99). CONCLUSION Statistically significant associations were observed between the response to anti-TNF therapy and an RA risk allele at the PTPRC gene locus. Additional studies will be required to replicate this finding in additional patient collections.

Genome-wide association study and gene expression analysis identifies CD84 as a predictor of response to etanercept therapy in rheumatoid arthritis.

Anti-tumor necrosis factor alpha (anti-TNF) biologic therapy is a widely used treatment for rheumatoid arthritis (RA). It is unknown why some RA patients fail to respond adequately to anti-TNF therapy, which limits the development of clinical biomarkers to predict response or new drugs to target refractory cases. To understand the biological basis of response to anti-TNF therapy, we conducted a genome-wide association study (GWAS) meta-analysis of more than 2 million common variants in 2,706 RA patients from 13 different collections. Patients were treated with one of three anti-TNF medications: etanercept (n = 733), infliximab (n = 894), or adalimumab (n = 1,071). We identified a SNP (rs6427528) at the 1q23 locus that was associated with change in disease activity score (ΔDAS) in the etanercept subset of patients (P = 8×10−8), but not in the infliximab or adalimumab subsets (P>0.05). The SNP is predicted to disrupt transcription factor binding site motifs in the 3′ UTR of an immune-related gene, CD84, and the allele associated with better response to etanercept was associated with higher CD84 gene expression in peripheral blood mononuclear cells (P = 1×10−11 in 228 non-RA patients and P = 0.004 in 132 RA patients). Consistent with the genetic findings, higher CD84 gene expression correlated with lower cross-sectional DAS (P = 0.02, n = 210) and showed a non-significant trend for better ΔDAS in a subset of RA patients with gene expression data (n = 31, etanercept-treated). A small, multi-ethnic replication showed a non-significant trend towards an association among etanercept-treated RA patients of Portuguese ancestry (n = 139, P = 0.4), but no association among patients of Japanese ancestry (n = 151, P = 0.8). Our study demonstrates that an allele associated with response to etanercept therapy is also associated with CD84 gene expression, and further that CD84 expression correlates with disease activity. These findings support a model in which CD84 genotypes and/or expression may serve as a useful biomarker for response to etanercept treatment in RA patients of European ancestry.

Mannan binding lectin as an adjunct to risk assessment for myocardial infarction in individuals with enhanced risk

Inflammation can predispose to myocardial infarction (MI), and mannan binding lectin (MBL) promotes phagocytic clearance of inflammatory agents, but the predictive value of MBL levels for MI is not known. MBL was analyzed in subgroups of the population-based Reykjavik study, a cohort of 19,381 participants recruited from 1967. MBL levels were very stable over time (self correlation: 0.86). In a cross-sectional group from the original cohort (n = 987), high MBL (>1,000 μg/L) was associated with a greatly lowered odds ratio for MI (0.64, P < 0.001). To verify this finding, a nested case control sample (n = 1,309) was randomly selected from the cohort. High MBL at recruitment was also associated with decreased MI risk in this follow-up group, but to a lesser extent and not significant for the whole group, smokers, or hypertensive individuals. However, high MBL was as in the cross-sectional group, associated with greatly decreased MI risk in diabetic (P = 0.02) or hypercholesterolemic individuals (P = 0.004). This also applied to raised erythrocyte sedimentation rate (P = 0.007). Diabetic patients with high MBL did not have a higher MI risk than nondiabetic individuals. Our findings indicate that high MBL may predict decreased likelihood of MI, particularly in diabetics, and are consistent with the possibility that MBL may promote clearance of atherogenic agents.

In early rheumatoid arthritis, patients with a good initial response to methotrexate have excellent 2-year clinical outcomes, but radiological progression is not fully prevented: data from the methotrexate responders population in the SWEFOT trial

Objective To investigate the 2-year clinical and radiological outcomes of patients with early rheumatoid arthritis (RA; symptom duration <1 year) who had initially responded well to methotrexate monotherapy. Methods In the SWEFOT trial, all 487 patients started methotrexate (target dose 20 mg/week). After 3–4 months, 147 had low disease activity, 28-joint based disease activity score (DAS28) ≤3.2. These patients were not randomly selected but were followed in regular care for 2 years. Clinical outcomes and radiographic progression according to the van der Heijde modified Sharp (SvdH) score were analysed. Results The majority of the 147 patients continued on methotrexate monotherapy. After 1 and 2 years, DAS28 remission was achieved in 59.6% and 71.8% and mean observed DAS28 values were 2.53 and 2.25, respectively. Despite the favourable clinical course, a proportion of the patients progressed radiographically with a mean (SD) increase in the SvdH score after 2 years of 3.90 (6.84). There was no significant difference in progression between patients in DAS28 remission versus not in remission (p=0.73). At baseline, approximately half the patients had no radiographic damage, while after 2 years the proportion was approximately 20%. Conclusion Most early RA patients who achieve low disease activity after 3–4 months of methotrexate monotherapy continue to have low disease activity during 2 years follow-up, and additional treatment is needed infrequently. Some radiological progression occurs in most patients, and may be marked or severe in some, even despite sustained DAS28 remission. Close monitoring for radiological progression is thus warranted.

Overweight decreases the chance of achieving good response and low disease activity in early rheumatoid arthritis.

Aim To investigate whether overweight/obesity at diagnosis affects the chances of decrease in disease activity and pain in early rheumatoid arthritis (RA). Method We investigated incident RA cases from the population-based Epidemiological Investigation of risk factors for Rheumatoid Arthritis (EIRA) study (2006–2009, N=495) with clinical follow-up in the Swedish Rheumatology Quality Register. At diagnosis, 93% received disease-modifying antirheumatic drugs (DMARDs) (86% methotrexate). The odds of achieving a good response according to the DAS28-based European League Against Rheumatism (EULAR) criteria, low disease activity (DAS28<3.2), remission (DAS28<2.6) or pain remission (visual analogue scale ≤20 mm) at 3-months and 6-months follow-up, were calculated using logistic regression, adjusting for potential confounders. Results Significant dose-response relationships were found between Body Mass Index (BMI) and change of disease activity as well as pain at both time points. Patients with BMI ≥25 had 51% lower odds of achieving low disease activity (odds ratio (OR=0.49 (95% CI 0.31 to 0.78)) and 42% lower odds of remission (OR=0.58 (95% CI 0.37 to 0.92)) at the 6-months visit, compared to normal-weight patients. This effect was also present at 3 months, where we also found a 43% decreased odds of pain remission (OR=0.57 (95% CI 0.37 to 0.88)). No effect modification was found for anti-citrullinated protein antibody (CCP)-status, sex, prednisolone treatment or DAS28 at diagnosis. Conclusions Overweight at diagnosis significantly decreases the chance of achieving good disease control during the early phase of RA.

Genome-wide association analysis of anti-TNF drug response in patients with rheumatoid arthritis

Background Treatment strategies blocking tumour necrosis factor (anti-TNF) have proven very successful in patients with rheumatoid arthritis (RA). However, a significant subset of patients does not respond for unknown reasons. Currently, there are no means of identifying these patients before treatment. This study was aimed at identifying genetic factors predicting anti-TNF treatment outcome in patients with RA using a genome-wide association approach. Methods We conducted a multistage, genome-wide association study with a primary analysis of 2 557 253 single-nucleotide polymorphisms (SNPs) in 882 patients with RA receiving anti-TNF therapy included through the Dutch Rheumatoid Arthritis Monitoring (DREAM) registry and the database of Apotheekzorg. Linear regression analysis of changes in the Disease Activity Score in 28 joints after 14 weeks of treatment was performed using an additive model. Markers with p<10−3 were selected for replication in 1821 patients from three independent cohorts. Pathway analysis including all SNPs with p<10−3 was performed using Ingenuity. Results 772 markers showed evidence of association with treatment outcome in the initial stage. Eight genetic loci showed improved p value in the overall meta-analysis compared with the first stage, three of which (rs1568885, rs1813443 and rs4411591) showed directional consistency over all four cohorts studied. We were unable to replicate markers previously reported to be associated with anti-TNF outcome. Network analysis indicated strong involvement of biological processes underlying inflammatory response and cell morphology. Conclusions Using a multistage strategy, we have identified eight genetic loci associated with response to anti-TNF treatment. Further studies are required to validate these findings in additional patient collections.

Pretreatment multi-biomarker disease activity score and radiographic progression in early RA: results from the SWEFOT trial

Objectives Prediction of radiographic progression (RP) in early rheumatoid arthritis (eRA) would be very useful for optimal choice among available therapies. We evaluated a multi-biomarker disease activity (MBDA) score, based on 12 serum biomarkers as a baseline predictor for 1-year RP in eRA. Methods Baseline disease activity score based on erythrocyte sedimentation rate (DAS28-ESR), disease activity score based on C-reactive protein (DAS28-CRP), CRP, MBDA scores and DAS28-ESR at 3 months were analysed for 235 patients with eRA from the Swedish Farmacotherapy (SWEFOT) clinical trial. RP was defined as an increase in the Van der Heijde-modified Sharp score by more than five points over 1 year. Associations between baseline disease activity measures, the MBDA score, and 1-year RP were evaluated using univariate and multivariate logistic regression, adjusted for potential confounders. Results Among 235 patients with eRA, 5 had low and 29 moderate MBDA scores at baseline. None of the former and only one of the latter group (3.4%) had RP during 1 year, while the proportion of patients with RP among those with high MBDA score was 20.9% (p=0.021). Among patients with low/moderate CRP, moderate DAS28-CRP or moderate DAS28-ESR at baseline, progression occurred in 14%, 15%, 14% and 15%, respectively. MBDA score was an independent predictor of RP as a continuous (OR=1.05, 95% CI 1.02 to 1.08) and dichotomised variable (high versus low/moderate, OR=3.86, 95% CI 1.04 to 14.26). Conclusions In patients with eRA, the MBDA score at baseline was a strong independent predictor of 1-year RP. These results suggest that when choosing initial treatment in eRA the MBDA test may be clinically useful to identify a subgroup of patients at low risk of RP. Trial registration number WHO database at the Karolinska Institute: CT20080004; and clinicaltrials.gov: NCT00764725.