Body mass index and clinical response to infliximab in rheumatoid arthritis

A systematic review of the association of obesity with the outcomes of inflammatory rheumatic diseases

This was a systematic review of the literature on the association between obesity and the outcome of inflammatory rheumatic diseases. We conducted a literature search using PubMed®, Embase and PsycINFO®. Articles were classified into three categories based on the effects of obesity on the outcomes of inflammatory rheumatic diseases. The subject population, country, type of studies, number of patients, measurement of obesity and outcomes assessed were presented. Quality was appraised using Kmet et al's criteria. 4,331 articles were screened and 60 were relevant to the objective. Obesity had a negative, positive and neutral association with outcomes of inflammatory rheumatic diseases in 38 (63.3%) studies with 57,612 subjects, 11 (18.3%) studies with 3,866 subjects, and 11 (18.3%) studies with 3,834 subjects, respectively. In most studies, the disease population had been diagnosed with rheumatoid arthritis (RA). Tumour necrosis factor-α inhibitors were mostly associated with negative outcomes. More studies examining subjects outside Europe and North America and diseases other than RA are warranted.

Plasma Leptin Does Not Reflect the Effect of High Body Mass Index on Disease Activity in Rheumatoid Arthritis

Background: The effect of obesity on disease severity in rheumatoid arthritis (RA) remains controversial. Adipocytes secrete pro-inflammatory cytokines and adipokines which may contribute to RA disease activity. The goal of the present study is to address the association between body mass index (BMI) with plasma levels of leptin, pro-inflammatory cytokines, and RA disease severity.Methods: Fifty RA patients (20 newly diagnosed and 30 under treatment) as well as 30 age- and sex-matched healthy subjects were included in this survey. The plasma levels of leptin and pro-inflammatory cytokines, including TNF-α and IL-6, were measured, and the results were compared among the patients in the three different categories of BMI, including <25, ≥25-30, and ≥30.Results: In our study, a significant positive correlation was observed between disease activity score-28 (DAS-28) and BMI in overweight (OW) RA patients (p = .036 r = 0.440). The plasma levels of leptin were significantly higher in patients group, compared to healthy subjects (p < .05); moreover, leptin levels were significantly higher in OW and obese patients compared to RA patients with normal BMI (p = .011, p = .001, respectively) and also BMI had positive correlation with leptin concentrations just in the newly diagnosed patients (p < .0001, r = 0.748). There was no correlation between leptin and DAS-28. The plasma IL-6 and TNF-α did not show significant differences between RA patients and healthy subjects, and also the plasma leptin did not have any correlation with plasma levels of IL-6 and TNF-α.Conclusion: BMI contribution to RA disease severity is independent of systemic levels of leptin and pro-inflammatory cytokines.

Body mass index and treatment response to subcutaneous abatacept in patients with psoriatic arthritis: a post hoc analysis of a phase III trial

Objective

This post hoc analysis of the phase III Active PSoriaTic Arthritis RAndomizEd TriAl (ASTRAEA) evaluated the effect of baseline body mass index (BMI) on subsequent response to subcutaneous (SC) abatacept in patients with psoriatic arthritis (PsA).

Methods

In ASTRAEA, patients with active PsA were randomised (1:1) to receive blinded weekly SC abatacept 125 mg or placebo for 24 weeks. Treatment response at week 24 was assessed by the proportions of patients achieving American College of Rheumatology 20% improvement response, Disease Activity Score in 28 joints (DAS28 (C reactive protein (CRP))) ≤3.6 and <2.6, Health Assessment Questionnaire-Disability Index reduction from baseline ≥0.35 and radiographic non-progression (defined as change from baseline ≤0 in PsA-modified total Sharp/van der Heijde score). Responses were stratified by baseline BMI (underweight/normal, <25 kg/m²; overweight, 25–30 kg/m²; obese, >30 kg/m²) and compared in univariate and multivariate models.

Results

Of 212/213 and 210/211 patients with baseline BMI data in the abatacept and placebo groups, respectively, 15% and 19% were underweight/normal, 36% and 27% were overweight, and 49% and 54% were obese. After adjusting for baseline characteristics, there were no significant differences for any outcome measure at week 24 with abatacept in the overweight or obese versus underweight/normal subgroup. In the placebo group, patients in the obese versus underweight/normal subgroup were significantly less likely to achieve DAS28 (CRP) <2.6 at week 24 (OR 0.26; 95% CI 0.08 to 0.87; p=0.03).

Conclusion

BMI does not impact clinical or radiographic response to SC abatacept in patients with PsA.

Trial registration number

NCT01860976.

Assessing prognosis and prediction of treatment response in early rheumatoid arthritis: systematic reviews

BACKGROUND

Rheumatoid arthritis (RA) is a chronic, debilitating disease associated with reduced quality of life and substantial costs. It is unclear which tests and assessment tools allow the best assessment of prognosis in people with early RA and whether or not variables predict the response of patients to different drug treatments.

OBJECTIVE

To systematically review evidence on the use of selected tests and assessment tools in patients with early RA (1) in the evaluation of a prognosis (review 1) and (2) as predictive markers of treatment response (review 2).

DATA SOURCES

Electronic databases (e.g. MEDLINE, EMBASE, The Cochrane Library, Web of Science Conference Proceedings; searched to September 2016), registers, key websites, hand-searching of reference lists of included studies and key systematic reviews and contact with experts.

STUDY SELECTION

Review 1 - primary studies on the development, external validation and impact of clinical prediction models for selected outcomes in adult early RA patients. Review 2 - primary studies on the interaction between selected baseline covariates and treatment (conventional and biological disease-modifying antirheumatic drugs) on salient outcomes in adult early RA patients.

RESULTS

Review 1 - 22 model development studies and one combined model development/external validation study reporting 39 clinical prediction models were included. Five external validation studies evaluating eight clinical prediction models for radiographic joint damage were also included. c-statistics from internal validation ranged from 0.63 to 0.87 for radiographic progression (different definitions, six studies) and 0.78 to 0.82 for the Health Assessment Questionnaire (HAQ). Predictive performance in external validations varied considerably. Three models [(1) Active controlled Study of Patients receiving Infliximab for the treatment of Rheumatoid arthritis of Early onset (ASPIRE) C-reactive protein (ASPIRE CRP), (2) ASPIRE erythrocyte sedimentation rate (ASPIRE ESR) and (3) Behandelings Strategie (BeSt)] were externally validated using the same outcome definition in more than one population. Results of the random-effects meta-analysis suggested substantial uncertainty in the expected predictive performance of models in a new sample of patients. Review 2 - 12 studies were identified. Covariates examined included anti-citrullinated protein/peptide anti-body (ACPA) status, smoking status, erosions, rheumatoid factor status, C-reactive protein level, erythrocyte sedimentation rate, swollen joint count (SJC), body mass index and vascularity of synovium on power Doppler ultrasound (PDUS). Outcomes examined included erosions/radiographic progression, disease activity, physical function and Disease Activity Score-28 remission. There was statistical evidence to suggest that ACPA status, SJC and PDUS status at baseline may be treatment effect modifiers, but not necessarily that they are prognostic of response for all treatments. Most of the results were subject to considerable uncertainty and were not statistically significant.

LIMITATIONS

The meta-analysis in review 1 was limited by the availability of only a small number of external validation studies. Studies rarely investigated the interaction between predictors and treatment.

SUGGESTED RESEARCH PRIORITIES

Collaborative research (including the use of individual participant data) is needed to further develop and externally validate the clinical prediction models. The clinical prediction models should be validated with respect to individual treatments. Future assessments of treatment by covariate interactions should follow good statistical practice.

CONCLUSIONS

Review 1 - uncertainty remains over the optimal prediction model(s) for use in clinical practice. Review 2 - in general, there was insufficient evidence that the effect of treatment depended on baseline characteristics.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016042402.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Body Mass Index and Clinical Response to Tocilizumab in Patients With Rheumatoid Arthritis

Objectives

This study aims to determine whether baseline body mass index (BMI) affects clinical response to tocilizumab (TCZ) after six months of treatment in rheumatoid arthritis (RA) patients.

Patients and methods

In this prospective study, a total of 52 RA patients (10 males, 42 females; mean age 50.6±12.2 years; range, 23 to 73 years) receiving intravenous TCZ were consecutively recruited and followed-up for six months. BMI was calculated before initiation of TCZ treatment. The primary clinical response criterion was clinical disease activity index (CDAI) low disease activity (LDA) and the secondary clinical response criteria included CDAI remission, disease activity score based on 28 joints (DAS28)-erythrocyte sedimentation rate (ESR) LDA, DAS28-ESR remission, European League Against Rheumatism (EULAR) good response, and decreased DAS28-ESR (ΔDAS28-ESR)≥1.2.

Results

The number of RA patients classified as normal weight, overweight, and obese according to baseline BMI was 38 (73.1%), eight (15.4%), and six (11.5%), respectively. Similar baseline BMI median levels were found between RA patients reaching CDAI LDA and non-LDA: 21.11 (18.94-23.72) versus 20.78 (20.03-22.29) (p=0.98), and non-significant difference in the proportion of responders between normal weight and overweight/obese RA patients was found (p=0.47). No significant difference was found when the secondary clinical response criteria were applied.

Conclusion

Our study demonstrates that BMI is not associated with clinical response to TCZ among RA patients and TCZ may be used to treat RA patients regardless of BMI levels.

TNF, but not hyperinsulinemia or hyperglycemia, is a key driver of obesity-induced monocytosis revealing that inflammatory monocytes correlate with insulin in obese male mice

Inflammation contributes to obesity-related hyperinsulinemia and insulin resistance, which often precede type 2 diabetes. Inflammation is one way that obesity can promote insulin resistance. It is not clear if the extent of obesity, hyperinsulinemia, or hyperglycemia, underpins changes in cellular immunity during diet-induced obesity. In particular, the requirement for obesity or directionality in the relationship between insulin resistance and monocyte characteristics is poorly defined. Inflammatory cytokines such as tumor necrosis factor (TNF) can contribute to insulin resistance. It is unclear if TNF alters monocytosis or specific markers of cellular immunity in the context of obesity. We measured bone marrow and blood monocyte characteristics in WT and TNF-/- mice that were fed obesogenic, high fat (HF) diets. We also used hyperglycemic Akita mice and mice implanted with insulin pellets in order to determine if glucose or insulin were sufficient to alter monocyte characteristics. We found that diet-induced obesity in male mice increased the total number of monocytes in blood, but not in bone marrow. Immature, inflammatory (Ly6Chigh ) monocytes decreased within the bone marrow and increased within peripheral blood of HF-fed mice. We found that neither hyperinsulinemia nor hyperglycemia was sufficient to induce the observed changes in circulating monocytes in the absence of diet-induced obesity. In obese HF-fed mice, antibiotic treatment lowered insulin and insulin resistance, but did not alter circulating monocyte characteristics. Fewer Ly6Chigh monocytes were present within the blood of HF-fed TNF-/- mice in comparison to HF-fed wild-type (WT) mice. The prevalence of immature Ly6Chigh monocytes in the blood correlated with serum insulin and insulin resistance irrespective of the magnitude of adipocyte or adipose tissue hypertrophy in obese mice. These data suggest that diet-induced obesity instigates a TNF-dependent increase in circulating inflammatory monocytes, which predicts increased blood insulin and insulin resistance independently from markers of adiposity or adipose tissue expansion.

Body Mass Index Impact on Disease Activity, Clinical and Sonographic Remission Rates in Patients with Rheumatoid Arthritis

AIM

To investigate the impact of body mass index (BMI) on clinical disease activity indices and clinical and sonographic remission rates in patients with rheumatoid arthritis (RA).

PATIENTS AND METHODS

Sixty-three patients with RA were categorized according to BMI score into three groups: normal (BMI<25), overweight (BMI 25-30) and obese (BMI≥30). Thirty-three of them were treated with conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs), and 30 with biologic DMARDs (bDMARDs). Patients underwent clinical and laboratory assessment and musculoskeletal ultrasound examination (MSUS) at baseline and at 6 months after initiation of therapy. We evaluated the rate of clinical and sonographic remission (defined as Power Doppler score (PD) = 0) and its correlation with BMI score.

RESULTS

In the csDMARDs group, 60% of the normal weight patients reached DAS28 remission; 33.3% of the overweight; and 0% of the obese patients. In the bDMARDs group, the percentage of remission was as follows: 60% in the normal weight subgroup, 33.3% in the overweight; and 15.8% in the obese. Within the csDMARDs treatment group, two significant correlations were found: BMI score-DAS 28 at 6th month, rs = .372, p = .033; BMI score-DAS 28 categories, rs = .447, p = .014. Within the bDMARDs group, three significant correlations were identified: BMI score-PDUS at sixth month, rs = .506, p =.004; BMI score-DAS 28, rs = .511, p = .004; BMI score-DAS 28 categories, rs = .592, p = .001. Sonographic remission rates at 6 months were significantly higher in the normal BMI category in both treatment groups.

CONCLUSION

BMI influences the treatment response, clinical disease activity indices and the rates of clinical and sonographic remission in patients with RA. Obesity and overweight are associated with lower remission rates regardless of the type of treatment.

Treatment Failure of TNF-α Inhibitors in Obese Patients With Inflammatory Bowel Disease-A Cohort Study

BACKGROUND

In treatment of inflammatory bowel disease (IBD) with anti-tumor necrosis factor-α agents (anti-TNF-α), obesity has been suspected as a cause of accelerated loss of response (LOR). We sought to determine whether overweight IBD patients have accelerated LOR when treated with anti-TNF-α agents, compared with normal weight IBD patients.

METHODS

We identified a cohort of adult IBD patients treated with anti-TNF-α agents at a Danish university hospital. Patients were grouped according to body mass index (BMI), and our main outcome was time to LOR. We performed survival analyses on LOR and calculated hazard ratios (HRs) with the normal weight group as the reference, while adjusting for confounders.

RESULTS

Of 210 eligible patients, 92 (44%) experienced LOR. One hundred eighty patients were treated with infliximab and 30 with adalimumab, 114 (54%) were normal weight, 51 (24%) were overweight, and 45 (21%) were obese. Regression analysis produced the following adjusted HRs, compared with the normal weight group: overweight 0.89 (95% confidence interval [CI], 0.51-1.56) and obese 1.31 (95% CI, 0.76-2.24), thus showing no statistically significant association between BMI and time to LOR. Subgroup analyses produced similar results, except for obese ulcerative colitis patients having an adjusted HR of 2.42 (95% CI, 1.03-5.70).

CONCLUSIONS

In IBD patients treated with anti-TNF-α agents, we found no overall association between increased BMI and accelerated LOR.

Clinical Responses and Synovial Vascularity in Obese Rheumatoid Arthritis Patients Treated with Adalimumab and Methotrexate

OBJECTIVE

Obese patients with rheumatoid arthritis (RA) report more joint swelling and tenderness and often have poorer responses to therapy than nonobese patients. The aim of this posthoc analysis of the MUSICA trial was to compare imaging and clinical disease activity measures in obese and nonobese patients with RA.

METHODS

MUSICA evaluated methotrexate (MTX) 20 mg/week versus 7.5 mg/week in combination with adalimumab (ADA) in RA patients with an inadequate response to MTX. Patients were categorized by baseline body mass index as normal (< 25), overweight (≥ 25 to < 30), or obese (≥ 30). Synovial vascularity and hypertrophy, swollen and tender joint counts (SJC and TJC), American College of Rheumatology (ACR) responses, and low disease activity (LDA), defined as Clinical Disease Activity Index < 10 and 28-joint count Disease Activity Score using C-reactive protein (DAS28-CRP) < 3.2, were assessed at weeks 12 and 24.

RESULTS

Patient characteristics were similar among groups at baseline. Obese patients had numerically smaller changes from baseline to weeks 12/24 in SJC, TJC, DAS28-CRP, and synovial hypertrophy and vascularity versus nonobese patients. Significantly fewer obese patients reached ACR20/50 at weeks 12 and 24, and LDA at Week 12; this difference was especially apparent in patients receiving 7.5 mg/week MTX but was no longer significant at Week 24.

CONCLUSION

Obese patients with RA had worse clinical and ultrasonographic responses than nonobese patients, which were partly overcome with time. Obese patients may experience better and faster clinical improvements if ADA is initiated with high-dose (20 mg/week) rather than low-dose MTX. [ClinicalTrials.gov: NCT01185288].

Chemerin and PEDF Are Metaflammation-Related Biomarkers of Disease Activity and Obesity in Rheumatoid Arthritis

Objective: Obesity is a risk factor for Rheumatoid Arthritis (RA) being associated to low grade inflammation. This study aimed to determine whether PEDF and Chemerin are biomarkers of inflammation related to fat accumulation in RA and to investigate whether weight loss associates with clinical disease improvement through the modification of fat-related biomarkers in overweight/obese RA with low-moderate disease.

Participants and Methods: Two-hundred and thirty RA patients were enrolled, of whom 176 at disease onset treated according to a treat-to-target strategy (T2T) and 54 overweight/obese RA in stable therapy and low-moderate disease activity. Gene expression of adipokines, interleukin-6 and their receptors were examined in adipose tissue from obese RA. Obese RA with low-moderate disease activity underwent low-calories diet aiming to Body Mass Index (BMI) reduction >5%, maintaining RA therapy unchanged. Chemerin, PEDF and Interleukin-6 plasma values were assessed by ELISA and disease activity was evaluated.

Results: At RA onset, PEDF and Chemerin plasma values correlated with BMI (p < 0.001) but only Chemerin plasma values correlated with disease activity (p < 0.001). After adopting a T2T strategy, Chemerin arose as an independent factor associated with remission in early RA [OR(95%CIs):0.49(0.25–0.97)]. Moreover, after low-calories diet, RA with low-moderate disease activity reaching BMI reduction ≥5% (62.6%) at 6 months had significant decrease of PEDF (p < 0.05) and Chemerin (p < 0.05) plasma values, in parallel with the improvement in disease activity.

Conclusions: PEDF and Chemerin arose as biomarkers of obesity and metaflammation respectively, providing a link between chronic inflammation and excess of body weight in RA. Therefore, BMI reduction of at least 5% in obese RA allowed better disease control without modifying RA treatment.

Management of Paediatric Ulcerative Colitis, Part 1: Ambulatory Care-An Evidence-based Guideline From European Crohn's and Colitis Organization and European Society of Paediatric Gastroenterology, Hepatology and Nutrition

BACKGROUND

The contemporary management of ambulatory ulcerative colitis (UC) continues to be challenging with ∼20% of children needing a colectomy within childhood years. We thus aimed to standardize daily treatment of pediatric UC and inflammatory bowel diseases (IBD)-unclassified through detailed recommendations and practice points.

METHODS

These guidelines are a joint effort of the European Crohn's and Colitis Organization (ECCO) and the Paediatric IBD Porto group of European Society of Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN). An extensive literature search with subsequent evidence appraisal using robust methodology was performed before 2 face-to-face meetings. All 40 included recommendations and 86 practice points were endorsed by 43 experts in Paediatric IBD with at least an 88% consensus rate.

RESULTS

These guidelines discuss how to optimize the use of mesalamine (including topical), systemic and locally active steroids, thiopurines and, for more severe disease, biologics. The use of other emerging therapies and the role of surgery are also covered. Algorithms are provided to aid therapeutic decision-making based on clinical assessment and the Paediatric UC Activity Index (PUCAI). Advice on contemporary therapeutic targets incorporating the use of calprotectin and the role of therapeutic drug monitoring are presented, as well as other management considerations around pouchitis, extraintestinal manifestations, nutrition, growth, psychology, and transition. A brief section on disease classification using the PIBD-classes criteria and IBD-unclassified is also part of these guidelines.

CONCLUSIONS

These guidelines provide a guide to clinicians managing children with UC and IBD-unclassified management to provide modern management strategies while maintaining vigilance around appropriate outcomes and safety issues.

Optimal search strategies for identifying moderators and predictors of treatment effects in PubMed

BACKGROUND

Treatment effects differ across patients. To guide selection of treatments for patients, it is essential to acknowledge these differences and identify moderators or predictors. Our aim was to generate optimal search strategies (commonly known as filters) for PubMed to retrieve papers identifying moderators and predictors of treatment effects.

METHODS

Six journals were hand-searched for articles on moderators or predictors. Selected articles were randomly allocated to a development and validation set. Search terms were extracted from the development set and tested for their performance. Search filters were created from combinations of these terms and tested in the validation set.

RESULTS

Of 4407 articles, 198 were considered to be relevant. The most sensitive filter in the development set '("Epidemiologic Methods" [MeSH] OR assign* OR control*[tiab] OR trial*[tiab]) AND therapy*[sh]' yielded in the validation set a sensitivity of 89% [88%-90%] and a specificity of 80% [79%-82%].

CONCLUSIONS

The search filters created in this study can help to efficiently retrieve evidence on moderators and predictors of treatment effect. Testing of the filters in multiple domains should reveal robustness across disciplines. These filters can facilitate the retrieval of evidence on moderators and predictors of treatment effects, helping the implementation of stratified or personalised health care.

Overweight, Obesity, and the Likelihood of Achieving Sustained Remission in Early Rheumatoid Arthritis: Results From a Multicenter Prospective Cohort Study

OBJECTIVE

Obesity is implicated in rheumatoid arthritis (RA) development, severity, outcomes, and treatment response. We estimated the independent effects of overweight and obesity on ability to achieve sustained remission (sREM) in the 3 years following RA diagnosis.

METHODS

Data were from the Canadian Early Arthritis Cohort, a multicenter observational trial of early RA patients treated by rheumatologists using guideline-based care. sREM was defined as Disease Activity Score in 28 joints (DAS28) <2.6 for 2 consecutive visits. Patients were stratified by body mass index (BMI) as healthy (18.5-24.9 kg/m² ), overweight (25-29.9 kg/m² ), and obese (≥30 kg/m² ). Cox regression was used to estimate the effect of the BMI category on the probability of achieving sREM over the first 3 years, controlling for age, sex, race, education, RA duration, smoking status, comorbidities, baseline DAS28, Health Assessment Questionnaire disability index, C-reactive protein level, and initial treatment.

RESULTS

Of 982 patients, 315 (32%) had a healthy BMI, 343 (35%) were overweight, and 324 (33%) were obese; 355 (36%) achieved sREM within 3 years. Initial treatment did not differ by BMI category. Compared to healthy BMI, overweight patients (hazard ratio [HR] 0.75 [95% confidence interval (95% CI) 0.58-0.98]) and obese patients (HR 0.53 [95% CI 0.39-0.71]) were significantly less likely to achieve sREM.

CONCLUSION

Rates of overweight and obesity were high (69%) in this early RA cohort. Overweight patients were 25% less likely, and obese patients were 47% less likely, to achieve sREM in the first 3 years, despite similar initial disease-modifying antirheumatic drug treatment and subsequent biologic use. This is the largest study demonstrating the negative impact of excess weight on RA disease activity and supports a call to action to better identify and address this risk in RA patients.

Obesity and Response to Infliximab in Patients with Inflammatory Bowel Diseases: Pooled Analysis of Individual Participant Data from Clinical Trials

OBJECTIVES

To assess whether obesity may affect response to infliximab, we conducted an individual participant data pooled analysis using data from clinical trials of infliximab in inflammatory bowel diseases (IBD), using the Yale Open Data Access (YODA) Project.

METHODS

We analyzed individual participant data from four clinical trials of infliximab in adults with IBD (ACCENT-I, SONIC, ACT-1, and -2). Patients were categorized as obese (body mass index [BMI] ≥ 30 kg/m²) vs. non-obese, and by quartiles based on BMI or weight at time of trial entry. Primary outcome was clinical remission (Crohn's disease activity index [CDAI] < 150 or pediatric CDAI <10, Mayo Clinic Score <3); secondary outcomes were clinical response and mucosal healing. Multivariable logistic regression analysis was performed, after adjusting for sex, smoking, disease activity, and concomitant prednisone and/or immunomodulators.

RESULTS

We included 1205 infliximab-treated patients (mean age 37 years, 51.6% males, 14% obese). Obesity was not associated with odds of achieving clinical remission (obese vs. non-obese: adjusted OR, 0.93 [95% CI, 0.47-1.46]; Q4 vs. Q1: aOR, 0.94 [0.61-1.47], p-value for trend = 0.97), clinical response (Q4 vs. Q1: aOR, 0.84 [0.52-1.35], p = 0.45) or mucosal healing (Q4 vs. Q1: aOR, 1.13 [0.55-2.34], p = 0.95). These results were consistent across strata based on disease type (Crohn's disease and ulcerative colitis) and trial design (induction and maintenance therapy).

CONCLUSIONS

Based on individual participant data pooled analysis, obesity is not associated with inferior response to infliximab in patients with IBD. Future studies examining the association between obesity and fixed-dose therapies are warranted.

Obesity and response to anti-tumor necrosis factor-α agents in patients with select immune-mediated inflammatory diseases: A systematic review and meta-analysis

OBJECTIVES

We sought to evaluate the association between obesity and response to anti-tumor necrosis factor-α (TNF) agents, through a systematic review and meta-analysis.

METHODS

Through a systematic search through January 24, 2017, we identified randomized controlled trials (RCTs) or observational studies in adults with select immune-mediated inflammatory diseases-inflammatory bowel diseases (IBD), rheumatoid arthritis (RA), spondyloarthropathies (SpA), psoriasis and psoriatic arthritis (PsA)-treated with anti-TNF agents, and reporting outcomes, stratified by body mass index (BMI) categories or weight. Primary outcome was failure to achieve clinical remission or response or treatment modification. We performed random effects meta-analysis and estimated odds ratios (OR) and 95% confidence interval (CI).

RESULTS

Based on 54 cohorts including 19,372 patients (23% obese), patients with obesity had 60% higher odds of failing therapy (OR,1.60; 95% CI,1.39-1.83;I2 = 71%). Dose-response relationship was observed (obese vs. normal BMI: OR,1.87 [1.39-2.52]; overweight vs. normal BMI: OR,1.38 [1.11-1.74],p = 0.11); a 1kg/m2 increase in BMI was associated with 6.5% higher odds of failure (OR,1.065 [1.043-1.087]). These effects were observed across patients with rheumatic diseases, but not observed in patients with IBD. Effect was consistent based on dosing regimen/route, study design, exposure definition, and outcome measures. Less than 10% eligible RCTs reported outcomes stratified by BMI.

CONCLUSIONS

Obesity is an under-reported predictor of inferior response to anti-TNF agents in patients with select immune-mediated inflammatory diseases. A thorough evaluation of obesity as an effect modifier in clinical trials is warranted, and intentional weight loss may serve as adjunctive treatment in patients with obesity failing anti-TNF therapy.

Baricitinib in Patients with Rheumatoid Arthritis and an Inadequate Response to Conventional Disease-Modifying Antirheumatic Drugs in United States and Rest of World: A Subset Analysis

INTRODUCTION

This article evaluates the efficacy and safety of baricitinib 4 mg versus placebo in United States including Puerto Rico (US) and rest of the world (ROW) subpopulations using data pooled from RA-BEAM and RA-BUILD, which enrolled patients with moderate-to-severe adult-onset rheumatoid arthritis (RA).

METHODS

In RA-BEAM, patients with an inadequate response (IR) to methotrexate, at least one X-ray erosion, and high sensitivity C-reactive protein (hsCRP) ≥ 6 mg/L were randomized to placebo or orally administered baricitinib 4 mg daily or subcutaneously administered adalimumab 40 mg every other week. In RA-BUILD, patients with an IR to at least one conventional synthetic disease-modifying antirheumatic drug (csDMARD) and with hsCRP ≥ 3.6 mg/L were randomized to placebo or baricitinib 2 or 4 mg daily. Patients in both trials were biologic naive. In this post hoc analysis, data from both studies were pooled (714 baricitinib 4 mg-treated, 716 placebo-treated patients).

RESULTS

Overall, 188 US and 1242 ROW patients were included. Subgroups differed in baseline characteristics including race, weight, age, time since RA diagnosis, current corticosteroid use, and previous csDMARD use. At weeks 12 and 24, baricitinib-treated patients had larger responses compared to placebo-treated patients for multiple efficacy outcomes: American College of Rheumatology 20/50/70 response, low disease activity, remission, Disease Activity Score 28-C-reactive protein, and Health Assessment Questionnaire-Disability Index. Overall, similar efficacy was observed in US and ROW subgroups with no notable safety differences between subgroups at weeks 12 or 24.

CONCLUSION

Baricitinib 4 mg was efficacious compared to placebo in US and ROW subpopulations. Safety was similar between subgroups.

FUNDING

Eli Lilly & Company and Incyte Corporation.

TRIAL REGISTRATION

ClinicalTrials.gov identifiers, NCT01721057; NCT01710358.

Impact of obesity on the efficacy of different biologic agents in inflammatory diseases: A systematic review and meta-analysis

OBJECTIVE

Obesity is a worldwide epidemic and a growing body of evidence suggests that it may affect the body's response to biologic agents. We investigated the influence of obesity on the efficacy of different biologic agents used to treat inflammatory diseases.

METHODS

Medline, EMBASE and the Cochrane Database were searched using relevant MeSH and keyword terms for obesity and bDMARDs. Articles were selected if they reported a clinical response in obese subjects relative to other BMI categories. Response and remission outcomes were assessed using meta-analysis and all other reported outcomes were summarized.

RESULTS

Among the 3850 records retrieved, 24 articles met the inclusion criteria, including 10 on rheumatoid arthritis (RA), 4 on axial spondyloarthritis (axSpA), 4 on Crohn's disease (CD), 4 on psoriasis (Ps) and 2 on psoriasic arthritis (PsA). Four biological disease-modifying anti-rheumatic drugs (bDMARDs) - anti-TNF agents, T cell co-stimulation inhibitor (abatacept), IL-6 inhibitor (tocilizumab), and B-cell depletion therapy (rituximab) - were involved. The meta-analysis showed that the odds to reach a good response or achieve remission were lower in obese (BMI>30kg/m²) than non-obese (BMI≤30kg/m²) patients who were treated with anti-TNF agents (good responder % in RA: OR 0.34, 95% CI 0.18-0.64; remission% in RA: OR 0.36, 95% CI 0.21-0.59; BASDAI50% in axSpA: OR 0.41, 95% CI 0.21-0.83), but no significant difference between obese and non-obese was found in patients treated with abatacept (good responder % in RA: OR 0.75, 95% CI 0.42-1.36; remission% in RA: OR 0.84, 95% CI 0.65-1.09) and tocilizumab (good responder % in RA: OR 1.08, 95% CI 0.44-2.63; remission% in RA: OR 0.91, 95% CI 0.50-1.66).

CONCLUSION

Obesity hampered the effect of anti-TNF agents, but not those of abatacept and tocilizumab, suggesting that a personalized treatment strategy should be considered for obese patients with inflammatory diseases.

Association of weight loss with improved disease activity in patients with rheumatoid arthritis: A retrospective analysis using electronic medical record data

Objective

To evaluate the association between weight loss and rheumatoid arthritis (RA) disease activity.

Methods

We conducted a retrospective cohort study of RA patients seen at routine clinic visits at an academic medical center, 2012-2015. We included patients who had ≥2 clinical disease activity index (CDAI) measures. We identified visits during follow-up where the maximum and minimum weights occurred and defined weight change and CDAI change as the differences of these measures at these visits. We defined disease activity improvement as CDAI decrease of ≥5 and clinically relevant weight loss as ≥5 kg. We performed logistic regression analyses to establish the association between improved disease activity and weight loss and baseline BMI category (≥25 kg/m² or <25 kg/m²). We built linear regression models to investigate the association between continuous weight loss and CDAI change among patients who were overweight/obese at baseline and who lost weight during follow-up.

Results

We analyzed data from 174 RA patients with a median follow-up of 1.9 years (IQR 1.3-2.4); 117 (67%) were overweight/obese at baseline, and 53 (31%) lost ≥5 kg during follow-up. Patients who were overweight/obese and lost ≥5 kg had three-fold increased odds of disease activity improvement compared to those who did not (OR 3.03, 95%CI 1.18-7.83). Among those who were overweight/obese at baseline, each kilogram weight loss was associated with CDAI improvement of 1.15 (95%CI 0.42-1.88). Our study was limited by using clinical data from a single center without fixed intervals for assessments.

Conclusion

Clinically relevant weight loss (≥5 kg) was associated with improved RA disease activity in the routine clinical setting. Further studies are needed for replication and to evaluate the effect of prospective weight loss interventions on RA disease activity.

Immunogenicity and loss of response to TNF inhibitors: implications for rheumatoid arthritis treatment

The availability of monoclonal antibodies has revolutionized the treatment of an increasingly broad spectrum of diseases. Inflammatory diseases are among those most widely treated with protein-based therapeutics, termed biologics. Following the first large-scale clinical trials with monoclonal antibodies performed in the 1990s by rheumatologists and clinical immunologists, the approval of these agents for use in daily clinical practice led to substantial progress in the treatment of rheumatic diseases. Despite this progress, however, only a proportion of patients achieve a long-term clinical response. Data on the use of agents blocking TNF, which were among the first biologics introduced into clinical practice, provide ample evidence of primary and secondary treatment inefficacy in patients with rheumatoid arthritis (RA). Important issues relevant to primary and secondary failure of these agents in RA include immunogenicity, methodological problems for the detection of antidrug antibodies and trough drug levels, and the implications for treatment strategies. Although there is no strong evidence to support the routine estimation of antidrug antibodies or serum trough levels during anti-TNF therapy, these assessments might be helpful in a few clinical situations; in particular, they might guide decisions on switching the therapeutic biologic in certain instances of secondary clinical failure.

Patients with Crohn's Disease with High Body Mass Index Present More Frequent and Rapid Loss of Response to Infliximab

BACKGROUND

Infliximab (IFX) is effective in inducing and maintaining remission in patients with luminal and anoperineal Crohn's disease (CD). However, treatment failure within 12 months after initiating IFX is observed in a significant proportion of patients. The aim of the present study was to determine whether the body mass index (BMI) affects response to IFX during the first year of treatment in patients with CD.

METHODS

All patients with luminal CD who began IFX between January 2010 and May 2014 were prospectively included. BMI was calculated before IFX treatment was begun, and patients were divided into 3 groups: normal BMI (BMI < 25 kg/m), overweight patients (BMI of 25.0-30 kg/m), and obese patients (BMI > 30.0 kg/m). The primary outcome was to evaluate the rate and delay of IFX optimization during the first year of treatment among normal weight, overweight, and obese patients.

RESULTS

One hundred forty patients were included. Demographic and clinical characteristics at IFX initiation were comparable among the 3 groups. Within 12 months after the initiation of IFX, the rate of IFX optimization was significantly higher in overweight and obese patients than in the normal BMI group: 52%, 56%, and 20%, respectively (P = 0.0002). The median time until optimization of IFX was significantly shorter in overweight and obese patients than in the normal BMI group: 7, 7, and 10 months, respectively (P = 0.03). A BMI >25 kg/m was significantly associated with IFX optimization within 12 months on multivariate analysis.

CONCLUSION

This is the first study to show that optimization of IFX is more frequent and faster in obese and overweight patients with CD and occurs within 12 months after beginning IFX, suggesting that an induction regimen with higher doses of IFX and a tight control of IFX concentrations may be needed in these patients.

Extraintestinal Manifestations Are Common in Obese Patients with Crohn's Disease

INTRODUCTION

Crohn's disease (CD) is a chronic condition associated with the risk of malabsorption. The incidence of obesity worldwide is increasing, and the effect of obesity on patients with CD is unknown. We aim to identify traits related to obesity in a cohort of patients with CD.

METHODS

We conducted a retrospective study of 209 adult patients with CD. Age, Montreal disease classification, sex, race, duration of disease, erythrocyte sedimentation rate, C-reactive protein levels, physician global assessment, endoscopic appearance, histologic activity, medication use, and body mass index (BMI) were collected about each patient.

RESULTS

The mean age was 43.4 ± 14.9 years; 68.9% were white, and 51.7% were male. The mean duration of disease was 11.0 ± 10.6 years. The mean BMI was 26.8 ± 5.7: underweight 7.7%; normal weight 29.3%; overweight 38.0%; and obese 25%. Patients with higher BMI were more likely to have extraintestinal manifestations (EIM) (P = 0.005) and more likely to have nonarthralgia extraintestinal manifestations (P = 0.047). There was a linear association between proximal CD and decreasing BMI (underweight 31.3%, normal weight 14.8%, overweight 15.0%, obese 7.7%; P = 0.046). There was no difference in BMI between patients with and without perianal disease (P = 0.216).

CONCLUSIONS

Most patients were overweight or obese, which correlates with national population trends. Our data suggest disease location plays a role in weight modulation in patients with CD. Increased extraintestinal manifestations in patients with high BMI suggests that the chronic inflammation associated with obesity may play a role in extraintestinal inflammation.

Obesity is a strong predictor of worse clinical outcomes and treatment responses in early rheumatoid arthritis: results from the SWEFOT trial

Objectives

The aim of this paper was to analyse the impact of obesity, in addition to known predictors, on disease outcome in early rheumatoid arthritis (RA).

Methods

Body mass index (BMI) was available in 260 patients from the Swedish pharmacotherapy trial (SWEFOT). Differences in disease activity (DAS28), functional impairment (HAQ), pain (Visual Analogue Scale, VAS-pain) and radiographic damage were evaluated over 24 months between BMI categories (obese BMI >30, n=43; overweight BMI=25–29.9, n=74; normal BMI <25, n=143) using non-parametric testing. Predictors of European League Against Rheumatism non-remission (DAS28 ≥2.6) at 24 months of follow-up were evaluated using binary univariate and multivariate logistic regression.

Results

Obesity at baseline was associated with worse continuous-scale clinical outcomes over 24 months (DAS28, HAQ and VAS-pain at last visit: obese vs normal: p<0.001; obese vs overweight: p<0.05). Furthermore, obese patients compared with non-obese patients had significantly greater odds of non-remission at 24 months (adjusted OR (aOR) 5.2; 95% CI 1.8 to 15.2). Other independent predictors were female sex (aOR 2.6; 95% CI 1.1 to 5.8), current smoking (aOR 2.6; 95% CI 1.1 to 6.3) and HAQ (per-unit increase, aOR 1.9; 95% CI 1.1 to 3.4). The pattern was similar among seropositive and seronegative patients; and in the subgroups of methotrexate responders and patients randomised at 3 months to add-on of sulfasalazine+hydroxychloroquine, although not significant with add-on of infliximab. Obesity had no independent association to radiographic progression.

Conclusions

In this early RA trial reflecting today’s standard treatment, obesity, in addition to sex, smoking and functional impairment strongly lowered the chance of attaining good clinical outcomes, including remission, today’s treatment goal. This highlights the importance of considering lifestyle modification as one of the cornerstones of RA care.

Trial registration number

NCT00764725; Post-results. WHO database at the Karolinska University Hospital: CT20080004.

Prediction of Response to Targeted Treatment in Rheumatoid Arthritis

Rheumatoid arthritis is an autoimmune syndrome presenting with chronic inflammation of the joints. Patients with the same diagnosis can present with different phenotypes. In some patients severe joint inflammation and early joint destruction are observed, whereas a milder phenotype can be seen in others. Conversely, patients with the same signs and symptoms may exhibit different immunological and molecular abnormalities. Since the introduction of early treatment in clinical practice, the treat to target principle, and new medicines such as biologic disease-modifying antirheumatic drugs, clinical remission can be achieved early in the disease course, albeit not in all patients. The clinical response and efficacy of biologic disease-modifying antirheumatic drugs vary among different individuals. Therefore, there is a need to develop a more personalized approach toward treatment to achieve rapid remission in every patient to prevent disability and restore and maintain quality of life, without unnecessary adverse effects, in a cost-effective manner. The latest data from explorative studies of predictive markers of response are discussed here, together with a preliminary treatment algorithm based on currently available knowledge.

Obesity and rates of clinical remission and low MRI inflammation in rheumatoid arthritis

OBJECTIVES

Obesity has been proposed as a risk factor for refractory rheumatoid arthritis (RA). We evaluated the impact of obesity on achieving clinical and imaging definitions of low disease activity.

METHODS

This study evaluated 470 patients with RA from GO-BEFORE and GO-FORWARD randomised clinical trials. Included patients had blinded clinical disease activity measures and MRI at baseline, 24 and 52 weeks. Synovitis, osteitis and total inflammation scores were determined using the RA MRI scoring system. Multivariable logistic regression analyses compared odds of achieving Disease Activity Score using 28 joints and C-reactive protein (DAS28-CRP) remission, low component measures, or low MRI inflammation measures at 24 weeks in patients with obesity versus no obesity.

RESULTS

At 24 weeks, patients with obesity were significantly less likely to achieve DAS28(CRP) remission (OR 0.47; 95% CI 0.24 to 0.92, p=0.03). In contrast, patients with obesity had similar odds of achieving low synovitis (OR 0.94; 95% CI 0.51 to 1.72, p=0.84) and inflammation scores (OR 1.16; 95% CI 0.61 to 2.22, p=0.64) and greater odds of achieving low osteitis scores (OR 2.06; 95% CI 1.10 to 3.84, p=0.02) versus normal weight patients.

CONCLUSIONS

Patients with RA and obesity have lower rates of DAS28 remission but similar rates of low MRI activity compared with patients without obesity, suggesting that obesity and its associated comorbidities can bias clinical disease activity measures.

TRIAL REGISTRATION NUMBER

NCT00361335 and NCT00264550; Post-results.

Increased serum concentrations of IL-1 beta, IL-21 and Th17 cells in overweight patients with rheumatoid arthritis

Backgrounds

Obesity is associated with worse disease activity and drug responses in patients with rheumatoid arthritis (RA). However, the immunological mechanisms responsible for the relationship between RA and obesity have not yet been clarified in detail. This study aimed to elucidate the immunological mechanisms contributing to the pathogenesis of RA in overweight patients.

Methods

The frequencies of CD4⁺ T cell, B cell and monocyte subsets were analyzed in RA (n = 81) and healthy donors (n = 99) by flow cytometry, and were compared between three groups (body mass index (BMI) <20,  ≥20 to 25, >25). Serum cytokines were measured using multiplex ELISA. Gene expression was analyzed by quantitative PCR. Clinical information was extracted from medical records.

Results

The frequencies of T helper (Th)17 (CD4⁺CD45RA-CXCR5-CXCR3-CCR6⁺) cells and plasmablasts (PB) were significantly increased in patients with RA with BMI >25. Significant correlation was observed between BMI and Th17 cells in patients with RA. No significant differences in cell frequencies between the three BMI groups were observed in the healthy donors. Serum interleukin (IL)-1β and IL-21 significantly correlated with BMI in RA patients. Gene expression patterns in Th17 cells from overweight patients with RA showed the characteristics of pathogenic Th17 cells.

Conclusions

Quantitative and qualitative changes in Th17 cells were characteristic in overweight patients with RA.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1308-y) contains supplementary material, which is available to authorized users.

Differential impact of obesity on the pathogenesis of RA or preclinical models is contingent on the disease status

OBJECTIVE

Studies were performed to uncover the significance of obesity in rheumatoid arthritis (RA) and preclinical models.

METHODS

Preclinical arthritis models were used to examine the impact of obesity on disease onset and remission. Conditioned media from RA adipose tissues were used to investigate the mechanism contributing to joint neutrophil influx and M1 macrophage differentiation observed in early and remission phases of arthritis.

RESULTS

We report that mice fed with high fat diet (HFD) have an earlier onset of collagen-induced arthritis (CIA) compared with mice on regular diet. However, the differences in CIA joint swelling between the two diet groups are lost once disease is established. We found that early arthritis triggered by obesity is due to elevated joint MIP2/interleukin-8 levels detected in CIA as well as in the RA and mouse adipose tissues and the effect of this chemokine on neutrophil recruitment. Although active disease progression is similarly affected in both diet groups, arthritis resolution is accelerated in lean mice while joint inflammation is sustained in obese mice. We document that HFD can prolong toll-like receptor (TLR)4-induced arthritis by increasing joint monocyte migration and further remodelling the recruited cells into M1 macrophages. Consistently, we show that adipose condition media can transform RA and wild-type naïve myeloid cells into M1 macrophages; however, this function is impaired by TLR4 blockade or deficiency.

CONCLUSIONS

We conclude that despite established disease being unaffected by obesity, the early and the resolution phases of RA are impacted by obesity through different mechanisms.

Joint-specific assessment of swelling and power Doppler in obese rheumatoid arthritis patients

Background

Clinical swollen joint examination of the obese rheumatoid arthritis (RA) patient can be difficult. Musculoskeletal Ultrasound (MSUS) has higher sensitivity than physical examination for swollen joints (SJ). The purpose of this study was to determine the joint-specific association between power Doppler (PDUS) and clinical SJ in RA across body mass index (BMI) categories.

Methods

Cross-sectional clinical and laboratory data were collected on 43 RA patients. PDUS was performed on 9 joints (wrist, metacarpalphalangeal 2–5, proximal interphalgeal 2/3 and metatarsalphalangeal 2/5). DAS28 and clinical disease activity index (CDAI) were calculated. Patients were categorized by BMI: <25, 25–30, and >30. Demographic and clinical characteristics were compared across BMI groups with Kruskal-Wallis test and chi-square tests. Joint-level associations between PDUS and clinically SJ were evaluated with mixed effects logistic regression models.

Results

While demographics and clinically-determined disease activity were similar among BMI groups, PDUS scores significantly differed (p = 0.02). Using PDUS activity as the reference standard for synovitis and clinically SJ as the test, the positive predictive value of SJ was significantly lower in higher BMI groups (0.71 in BMI < 25, 0.58 in BMI 25–30 and 0.44 in BMI < 30) (p = 0.02). The logistic model demonstrated that increased BMI category resulted in decreased likelihood of PDUS positivity (OR 0.52, p = 0.03).

Conclusions

This study suggests that in an obese RA patient, a clinically assessed SJ is less likely to represent true synovitis (as measured by PDUS). Disease activity in obese RA patients may be overestimated by CDAI/DAS28 calculations and clinicians when considering change in therapy.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-017-1406-7) contains supplementary material, which is available to authorized users.

Obesity in IBD: epidemiology, pathogenesis, disease course and treatment outcomes

Incidence of IBD is rising in parallel with overweight and obesity. Contrary to conventional belief, about 15-40% of patients with IBD are obese, which might contribute to the development of IBD. Findings from cross-sectional and retrospective cohort studies are conflicting on the effect of obesity on natural history and course of IBD. Most studies are limited by small sample size, low event rates, non-validated assessment of disease activity and lack robust longitudinal follow-up and have incomplete adjustment for confounding factors. The effect of obesity on the efficacy of IBD-related therapy remains to be studied, though data from other autoimmune diseases suggests that obesity results in suboptimal response to therapy, potentially by promoting rapid clearance of biologic agents leading to low trough concentrations. These data provide a rationale for using weight loss interventions as adjunctive therapy in patients with IBD who are obese. Obesity also makes colorectal surgery technically challenging and might increase the risk of perioperative complications. In this Review, we highlight the existing literature on the epidemiology of obesity in IBD, discuss its plausible role in disease pathogenesis and effect on disease course and treatment response, and identify high-priority areas of future research.

Impact of Obesity on Remission and Disease Activity in Rheumatoid Arthritis: A Systematic Review and Meta-Analysis

OBJECTIVE

To summarize the relationship between obesity and remission in rheumatoid arthritis (RA); secondary objectives were to summarize other measures of treatment response and mortality in RA.

METHODS

Medline and Embase searches were performed in March 2016 using relevant MeSH and keyword terms for obesity and RA. Articles were selected if they reported estimates for achieving remission in obese subjects relative to other body mass index (BMI) categories, or changes in composite or individual disease activity measures or patient-reported outcomes during therapy, or mortality rates, in relation to BMI category or on a continuous scale. Remission outcomes were conducive to meta-analysis, and all other outcomes were summarized.

RESULTS

A total of 3,368 records were screened; we included 8 reporting remission rates, 9 reporting disease activity measures or patient-reported outcomes, and 3 examining mortality by obesity status or BMI. Obese patients attain remission less frequently than nonobese and/or normal-weight patients. In adjusted models, obese patients demonstrated lower odds of achieving remission (pooled odds ratio [OR] 0.57 [95% confidence interval (95% CI) 0.45, 0.72]) and sustained remission (pooled OR 0.49 [95% CI 0.32, 0.74]) relative to nonobese subjects. Most studies found obese patients to have worse Disease Activity Scores or Disease Activity Scores in 28 joints, tender joint counts, inflammatory markers, patient global evaluation scores, pain scores, and physical function scores during followup, but not worse swollen joint counts. Obesity was not associated with increased mortality.

CONCLUSION

Obesity decreases the odds of achieving remission in RA and negatively impacts disease activity and patient-reported outcomes during therapy. Interventions to reduce BMI should be investigated for their ability to improve disease outcomes.

Body mass does not impact the clinical response to intravenous abatacept in patients with rheumatoid arthritis. Analysis from the "pan-European registry collaboration for abatacept (PANABA)

Some evidences suggest that obesity impairs the effectiveness of TNF inhibitors. We examined the impact of body mass index (BMI) on the clinical effectiveness of abatacept in rheumatoid arthritis (RA) patients. This is a pooled analysis of 10 prospective cohorts of RA patients. All patients with available BMI were included in this study. The primary endpoint was drug retention of abatacept in the different BMI categories. Multivariable Cox regression was used to estimate hazard ratios (HRs) for drug discontinuation. A secondary endpoint was EULAR/LUNDEX response rates at 6/12 months. Of the 2015 RA patients initiating therapy with IV abatacept, 380 (18.9%) were classified as obese. Obese patients had more functional disability, and were less often RF positive. The median abatacept retention time was 1.91 years for obese RA patients compared to 2.12 years for non-obese patients (p = 0.15). The risk of abatacept discontinuation was not significantly different for overweight (HR 1.03 (95% CI 0.89-1.19)), or for obese (HR 1.08 (95% CI 0.89-1.30)) compared to normal-weight patients. Rheumatoid factor positivity reduced the risk of abatacept discontinuation (HR 0.83 (95% CI 0.72-0.95)), while previous biologic therapy was positively associated with drug interruption (HRs increasing from 1.68 to 2.16 with the line of treatments). Obese and non-obese patients attained similar rates of EULAR/LUNDEX clinical response at 6/12 months. Drug retention and clinical response rates to abatacept do not seem to be decreased by obesity in RA patients.

Impact of body weight on the achievement of minimal disease activity in patients with rheumatic diseases: a systematic review and meta-analysis

Background

In this study, we evaluated the impact of obesity and/or overweight on the achievement of minimal disease activity (MDA) in patients with psoriatic arthritis (PsA) and patients with rheumatoid arthritis (RA) receiving an anti-rheumatic treatment. Obesity can be considered a low-grade, chronic systemic inflammatory disease and some studies suggested that obese patients with rheumatic diseases exhibit a lower rate of low disease activity achievement during treatment with anti-rheumatic drugs.

Methods

A systematic search was performed in major electronic databases (PubMed, Web of Science, Scopus, Embase) to identify studies reporting MDA achievement in obese and/or overweight patients with RA or PsA and in normal-weight RA or PsA control subjects. Results were expressed as Odds Ratios (ORs) with pertinent 95% Confidence Intervals (95%CIs).

Results

We included 17 studies (10 on RA and 7 on PsA) comprising a total of 6693 patients (1562 with PsA and 5131 with RA) in the analysis. The MDA achievement rate was significantly lower in obese patients than in normal-weight subjects (OR 0.447, 95% CI 0.346–0.577, p < 0.001, I² = 62.6%, p < 0.001). Similarly, overweight patients showed a significantly lower prevalence of MDA achievement than normal-weight subjects (OR 0.867, 95% CI 0.757–0.994, p = 0.041, I² = 64%, p = 0.007). Interestingly, the effect of obesity on MDA was confirmed when we separately analyzed data on patients with RA and patients with PsA. In contrast, when we evaluated the effect of overweight, our results were confirmed for PsA but not for RA. A meta-regression analysis showed that follow-up duration, age, male sex, and treatment duration are covariates significantly affecting the effect of obesity/overweight on MDA achievement.

Conclusions

The results of our meta-analysis suggest that obesity and overweight reduce the chances to achieve MDA in patients with rheumatic diseases receiving treatment with traditional or biologic disease-modifying antirheumatic drugs.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-016-1194-8) contains supplementary material, which is available to authorized users.

Body mass index and response to abatacept in rheumatoid arthritis

BACKGROUND

Previous studies suggested that obesity could negatively affect the response to antitumour necrosis factor-α (TNFα) agents in rheumatoid arthritis (RA). However, data are lacking on whether obesity affects the response to abatacept (ABA). We aimed to determine whether body mass index (BMI) affects the response to ABA in RA.

MATERIALS AND METHODS

In this multicenter retrospective study, we included RA patients who received ABA. BMI was calculated at the initiation of treatment. After 6 months of treatment, change from baseline in DAS28, pain on a visual analog scale, erythrocyte sedimentation rate and C-reactive protein level, tender and swollen joint count were analysed. The primary endpoint was decrease in DAS28 ≥ 1·2. Secondary outcomes were good response and remission by EULAR criteria.

RESULTS

At baseline, among 141 RA patients included, the median [interquartile range] BMI was 26·0 [22·9-30·8] kg/m². The number of patients with normal weight, overweight and obesity was 64 (45·4%), 38 (27%) and 39 (27·6%), respectively. Baseline characteristics did not differ among the three BMI subgroups. Univariate analysis revealed no difference in BMI between responders and nonresponders: DAS28 decrease ≥ 1·2 (25·0 [23·4-31·3] vs. 26·3 [22·9-30·2], P = 0·95), EULAR good response (26·4 [23·5-30·9] vs. 26·0 [22·9-30·6], P = 0·96) and remission (26·7 [21·7-30·3] vs. 26·0 [23·0-30·1], P = 0·83).

CONCLUSION

In our real-life study, BMI did not affect the response to ABA in RA. If confirmed, these results suggest that obesity is not a limitation of ABA use in RA.

The influence of obesity on response to tumour necrosis factor-α inhibitors in psoriatic arthritis: results from the DANBIO and ICEBIO registries

OBJECTIVES

To investigate the impact of obesity on response to the first TNF-α inhibitor (TNFI) treatment course in patients with PsA followed in routine care.

METHODS

We performed an observational cohort study based on the Danish and Icelandic biologics registries. Kaplan-Meier plots, Cox and logistic regression analyses were performed to study the impact of obesity (BMI ⩾30 kg/m²) on TNFI adherence and response after 6 months (according to 20/50/70% improvement in ACR criteria and EULAR criteria). Subanalyses studied the impact of obesity according to gender, TNFI type and nationality.

RESULTS

Among 1943 PsA patients (193 Icelandic/1750 Danish) identified in the registries, 1271 (65%) had available BMI and 408 (32%) were obese. The median follow-up-time was 1.5 years [interquartile range (IQR) 0.5-3.9]. Obese patients had higher baseline disease activity, for example, 28-joint DAS [mean 4.6 (sd 1.2) vs 4.4 (1.2)]; CRP [median 9 mg/l (IQR 5-19) vs 7 (3-18)] and visual analogue scale-pain [66 mm (IQR 48-76) vs 60 (38-74)], compared with non-obese patients (all P < 0.05). TNFI adherence was shorter in obese patients, especially among men, where the median TNFI duration was 2.5 years (95% CI 1.7, 3.2) in obese vs 5.9 (4.1, 7.7) in non-obese patients (P < 0.01). A EULAR good or moderate (EGOM) response was achieved by 55% of obese vs 65% of non-obese patients after 6 months (P = 0.02). In multivariable analyses, obesity increased the risk of TNFI withdrawal [hazard ratio 1.6 (95% CI 1.3, 2.0)] and reduced odds for EGOM response [odds ratio 0.47 (95% CI 0.29, 0.72)]. The impact of obesity was significant across genders, TNFI types and nationality.

CONCLUSION

Obesity was associated with higher disease activity and seemed to diminish response and adherence to TNFIs in PsA.

The Obesity Epidemic and Consequences for Rheumatoid Arthritis Care

With the prevalence of obesity increasing dramatically worldwide over the past several decades, an increasing body of literature has examined the impact of obesity in the context of rheumatoid arthritis (RA). Epidemiologic studies suggest that obesity may be associated with a modestly increased risk for the development of RA, although these studies have shown conflicting results. Among patients with established RA, obesity has been observed to be associated with greater subjective measures of disease activity and poor treatment response, but also with a decreased risk of joint damage and lower mortality. A comprehensive evaluation of the influence of obesity on the measurement of disease, response to therapies, and long-term prognosis is critical in order to understand these observations. This review therefore focuses on recent observations, potential explanations for these findings, and implications for clinicians and investigators caring for and studying patients with RA.

Impact of Bariatric Surgery on Patients With Rheumatoid Arthritis

OBJECTIVE

To investigate the effect of weight loss after bariatric surgery among patients with rheumatoid arthritis (RA).

METHODS

We conducted a retrospective cohort study of RA patients who underwent bariatric surgery (Roux-en-Y gastric bypass, laparoscopic adjustable gastric banding, or sleeve gastrectomy) at 2 medical centers. We obtained information on anthropometrics, laboratory values, RA disease activity, and medication use at baseline (prior to surgery), at 6 and 12 months following surgery, and at the most recent followup visits. RA disease activity was determined by clinical or validated measures. At each postsurgical visit, characteristics were compared to baseline.

RESULTS

We identified 53 RA patients who underwent bariatric surgery. At baseline prior to surgery, mean ± SD body mass index was 47.8 ± 7.7 kg/m(2), mean ± SD weight was 128.2 ± 24.1 kg, and 57% had moderate to high RA disease activity. Twelve months following surgery, subjects lost a mean ± SD weight of 41.0 ± 17.3 kg, mean ± SD 70% ± 24% excess weight (P < 0.001). RA disease activity significantly improved at postsurgical visits (P < 0.001). At 12 months following surgery, 6% had moderate to high disease activity, compared to 57% at baseline (P < 0.001). At the most recent followup (mean ± SD 5.8 ± 3.2 years after surgery), 74% were in remission, compared to 26% at baseline (P < 0.001). Subjects had significantly lower erythrocyte sedimentation rate, C-reactive protein level, and RA-related medication use at followup visits compared to baseline (P < 0.05).

CONCLUSION

After substantial weight loss from bariatric surgery, RA patients had lower disease activity, decreased serum inflammatory markers, and less RA-related medication use. Weight loss may be an important nonpharmacologic strategy to reduce RA disease activity. However, other factors, such as improved efficacy of medications, improved physical activity, and metabolic changes, may also have contributed to these postsurgical improvements.

A Personalized Approach to Biological Therapy Using Prediction of Clinical Response Based on MRP8/14 Serum Complex Levels in Rheumatoid Arthritis Patients

Objectives

Measurement of MRP8/14 serum levels has shown potential in predicting clinical response to different biological agents in rheumatoid arthritis (RA). We aimed to develop a treatment algorithm based on a prediction score using MRP8/14 measurements and clinical parameters predictive for response to different biological agents.

Methods

Baseline serum levels of MRP8/14 were measured in 170 patients starting treatment with infliximab, adalimumab or rituximab. We used logistic regression analysis to develop a predictive score for clinical response at 16 weeks. MRP8/14 levels along with clinical variables at baseline were investigated. We also investigated how the predictive effect of MRP8/14 was modified by drug type. A treatment algorithm was developed based on categorizing the expected response per drug type as high, intermediate or low for each patient and optimal treatment was defined. Finally, we present the utility of using this treatment algorithm in clinical practice.

Results

The probability of response increased with higher baseline MRP8/14 complex levels (OR = 1.39), differentially between the TNF-blockers and rituximab (OR of interaction term = 0.78), and also increased with higher DAS28 at baseline (OR = 1.28). Rheumatoid factor positivity, functional disability (a higher HAQ), and previous use of a TNF-inhibitor decreased the probability of response. Based on the treatment algorithm 80 patients would have been recommended for anti-TNF treatment, 8 for rituximab, 13 for another biological treatment (other than TNFi or rituximab) and for 69 no recommendation was made. The predicted response rates matched the observed response in the cohort well. On group level the predicted response based on the algorithm resulted in a modest 10% higher response rate in our cohort with much higher differences in response probability in individual patients treated contrary to treatment recommendation.

Conclusions

Prediction of response using MRP8/14 levels along with clinical predictors has potential in personalizing treatment for RA patients starting biological anti-rheumatic treatment, and might increase cost-effectiveness.

Biomolecular features of inflammation in obese rheumatoid arthritis patients: management considerations

Adipose tissue is an active organ playing a role not only in metabolism but also in immune and inflammatory processes, releasing several pro-inflammatory mediators. This can explain the possible association between obesity and rheumatoid arthritis (RA) and its role in the progression of the disease. Adipose and synovial tissues share common histological features of local inflammation in terms of activation of target tissues infiltrating cells (i.e. myeloid cells). Among the so-called adipocytokines, PEDF and Chemerin orchestrate the cellular cross-talk between adipose and myeloid cells, being possible biomarkers to monitor the effect of weight loss or the decrease of adipose tissue in patients with RA. Moreover, dietary intervention has been demonstrated to reduce Chemerin as well as IL-6 and MCP-1 expression. Finally, epigenetic regulators such as micro-RNAs (i.e. miR-155) are key regulators of myeloid cells activation in RA and obesity as well as in adipocytes. In this review, we will summarize the biological link between obesity/overweight state and RA focusing on pathophysiological mechanisms, consequences and management considerations.

Evaluation of switching from intravenous to subcutaneous formulation of tocilizumab in patients with rheumatoid arthritis

OBJECTIVE

To evaluate the efficacy of switching the route from intravenous tocilizumab (TCZ) infusion (TCZ-IV) to subcutaneous TCZ injection (TCZ-SC) in a real-world setting through a comparison of the clinical response.

METHODS

Fifty-eight rheumatoid arthritis (RA) patients, for whom TCZ-SC was initiated following TCZ-IV between June 2013 and August 2014, were consecutively enrolled. Disease activity score (DAS)28-ESR, simplified disease activity index (SDAI), and clinical disease activity index (CDAI) were examined at baseline and after switching from TCZ-IV to TCZ-SC for 3 months. We investigated whether body weight and body mass index (BMI) affected the efficacy of TCZ-SC.

RESULTS

Most of the patients had achieved remission or low disease activity at baseline (77.6% examined by DAS28). Fifty-seven patients (98%) continued the TCZ-SC treatment, and the disease activity was well controlled after 3 months. ΔDAS28 tended to be worsened after switching to TCZ-SC in the high-body-weight groups (≥60 kg) as compared with the groups with body weight <60 kg, although no statistical significance was found. BMI did not affect the efficacy of TCZ-SC.

CONCLUSIONS

Caution should be exercised in the high-body-weight subjects, but these data indicate that TCZ-SC maintains the favorable RA disease activity established using TCZ-IV.

Body mass index and response to tocilizumab in rheumatoid arthritis: a real life study

Several studies have suggested that obesity could have a negative effect on response to anti-tumor necrosis factor α (anti-TNFα) in rheumatoid arthritis (RA). Little is known about the impact of body mass index (BMI) on other biologic agents. We aimed to evaluate the effect of BMI on response to tocilizumab (TCZ) in RA. RA patients treated with TCZ were included in this multicenter retrospective study. BMI was calculated at the initiation of treatment. After 6 months of treatment, change from baseline in DAS28, pain on a visual analog scale, erythrocyte sedimentation rate and C-reactive protein level, and tender and swollen joints were analyzed. The primary endpoint was decrease in DAS28 ≥ 1.2. Secondary outcomes were good response and remission by EULAR criteria. At baseline, among 115 RA patients included, the median (interquartile range) BMI was 25.4 (22.0-28.8) kg/m(2). The number of patients with normal weight, overweight, and obesity was 53 (46 %), 37 (32 %), and 25 (22 %), respectively. Baseline characteristics did not differ between the three subgroups of BMI. The median BMI did not differ between responders and non-responders for DAS28 decrease ≥1.2 (25.7 [22.1-29.9] vs 24.9 [22.0-27.1], P = 0.38), EULAR good response (25.9 [22.8-30.0] vs 25.4 [22.0-28.4], P = 0.61), and remission (25.1 [22.5-28.6] vs 25.4 [22.0-28.9], P = 0.76). BMI did not affect the response to TCZ in RA. If confirmed, these results could be helpful for the selection of a biologic agent in obese RA patients.

Personalized biological treatment for rheumatoid arthritis: a systematic review with a focus on clinical applicability

OBJECTIVES

To review studies that address prediction of response to biologic treatment in RA and to explore the clinical utility of the studied (bio)markers.

METHODS

A search for relevant articles was performed in PubMed, Embase and Cochrane databases. Studies that presented predictive values or in which these could be calculated were selected. The added value was determined by the added value on prior probability for each (bio)marker. Only an increase/decrease in chance of response ⩾15% was considered clinically relevant, whereas in oncology values >25% are common.

RESULTS

Of the 57 eligible studies, 14 (bio)markers were studied in more than one cohort and an overview of the added predictive value of each marker is presented. Of the replicated predictors, none consistently showed an increase/decrease in probability of response ⩾15%. However, positivity of RF and ACPA in case of rituximab and the presence of the TNF-α promoter 308 GG genotype for TNF inhibitor therapy were consistently predictive, yet low in added predictive value. Besides these, 65 (bio)markers studied once showed remarkably high (but not validated) predictive values.

CONCLUSION

We were unable to address clinically useful baseline (bio)markers for use in individually tailored treatment. Some predictors are consistently predictive, yet low in added predictive value, while several others are promising but await replication. The challenge now is to design studies to validate all explored and promising findings individually and in combination to make these (bio)markers relevant to clinical practice.

Association of Body Mass Index Categories with Disease Activity and Radiographic Joint Damage in Rheumatoid Arthritis: A Systematic Review and Metaanalysis

OBJECTIVE

Obesity and overweight are increasing conditions. Adipose tissue with proinflammatory properties could be involved in rheumatoid arthritis (RA) activity and radiographic progression. This study aims to investigate the influence of overweight and obesity on RA activity and severity.

METHODS

We conducted a systematic review and metaanalysis to assess the association of body mass index (BMI) categories with the Disease Activity Score in 28 joints (DAS28), functional disability [Health Assessment Questionnaire (HAQ)], and radiographic joint damage in patients with RA. We searched Medline through PubMed, EMBASE, and the Cochrane Database of Systematic Reviews for all studies assessing DAS28, HAQ, or/and radiographic damage according to predefined BMI groups.

RESULTS

Among the 737 citations retrieved, 58 articles met the inclusion criteria and 7 were included in the metaanalysis. DAS28 was higher in obese (BMI > 30 kg/m(2)) than non-obese (BMI ≤ 30 kg/m(2)) patients (mean difference 0.14, 95% CI 0.01-0.27, p = 0.04, I(2) = 0%). HAQ score was also higher among obese patients (mean difference 0.10, 95% CI 0.01-0.19, p = 0.03, I(2) = 0%). Radiographic joint damage was negatively associated with obesity (standardized mean difference -0.15, 95% CI -0.29 to -0.02, p = 0.03, I(2) = 38%).

CONCLUSION

Obesity in RA is associated with increased DAS28 and HAQ score and with lower radiographic joint damage. These associations mainly result from an increase of subjective components of the DAS28 (total joint count and global health assessment) in obese patients. Conflicting results were reported concerning inflammation markers (C-reactive protein and erythrocyte sedimentation rate).

Evidence-based Recommendations for the Management of Comorbidities in Rheumatoid Arthritis, Psoriasis, and Psoriatic Arthritis: Expert Opinion of the Canadian Dermatology-Rheumatology Comorbidity Initiative

Objective.

Comorbidities such as cardiovascular diseases (CVD), cancer, osteoporosis, and depression are often underrecognized in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), or psoriasis (PsO). Recommendations may improve identification and treatment of comorbidities. The Canadian Dermatology-Rheumatology Comorbidity Initiative reviewed the literature to develop practical evidence-based recommendations for management of comorbidities in patients with RA, PsA, and PsO.

Methods.

Eight main topics regarding comorbidities in RA, PsA, and PsO were developed. MEDLINE, EMBASE, and the Cochrane Library (1960–12/2012), together with abstracts from major rheumatology and dermatology congresses (2010–2012), were searched for relevant publications. Selected articles were analyzed and metaanalyses performed whenever possible. A meeting including rheumatologists, dermatologists, trainees/fellows, and invited experts was held to develop consensus-based recommendations using a Delphi process with prespecified cutoff agreement. Level of agreement was measured using a 10-point Likert scale (1 = no agreement, 10 = full agreement) and the potential effect of recommendations on daily clinical practice was considered. Grade of recommendation (ranging from A to D) was determined according to the Oxford Centre for Evidence-Based Medicine evidence levels.

Results.

A total of 17,575 articles were identified, of which 407 were reviewed. Recommendations were synthesized into 19 final recommendations ranging mainly from grade C to D, and relating to a large spectrum of comorbidities observed in clinical practice: CVD, obesity, osteoporosis, depression, infections, and cancer. Level of agreement ranged from 80.9% to 95.8%.

Conclusion.

These practical evidence-based recommendations can guide management of comorbidities in patients with RA, PsA, and PsO and optimize outcomes.

Cachexia and adiposity in rheumatoid arthritis. Relevance for disease management and clinical outcomes

Altered body composition is a frequent finding in rheumatoid arthritis and is associated with the two major outcomes of the disease: disability and cardiovascular mortality. It is estimated that up to two thirds of patients may be affected by loss of lean mass, the so-called rheumatoid cachexia. Hence, body weight being equal, the relative amount of lean mass is lower and that of body fat is higher in rheumatoid arthritis patients vs. healthy controls. Both disease-related factors and other factors, like drug treatments, physical activity and nutrition contribute to modify body composition in rheumatoid arthritis. The effect of pharmacological treatments, and notably of anti-TNF drugs, on body composition is controversial. Conversely, training programs to stimulate muscle growth can restore lean mass and reduce adiposity. There is good evidence that amelioration of body composition ameliorates function and reduces disability. Currently, there is no evidence that interventions that modify body composition can reduce cardiovascular morbidity and mortality in rheumatoid arthritis.

Obesity and inflammatory arthritis: impact on occurrence, disease characteristics and therapeutic response

Overweight and obesity are increasing worldwide and now reach about one-third of the world's population. Obesity also involves patients with inflammatory arthritis. Knowing the impact of obesity on rheumatic diseases (rheumatoid arthritis, ankylosing spondylitis and psoriatic arthritis) is thus an important issue. This article first reviews the epidemiological and clinical data available on obesity in inflammatory rheumatic diseases, that is, its impact on incident disease, disease characteristics and the therapeutic response. The second part of this review gives an overview of the factors potentially involved in the specifics of inflammatory arthritis in patients with obesity, such as limitations in the clinical assessment, diet, microbiota and adipokines.

The role of leptin in the pathophysiology of rheumatoid arthritis

The past 20 years of research on leptin has provided important insights into its role in rheumatoid arthritis (RA). Leptin is one of the different adipokines produced by the adipose tissue that influences the endocrine system, energy homeostasis and the immune response in several ways. Leptin is known to have predominantly pro-inflammatory effects, especially in the setting of chronic inflammation. Animal models of arthritis have illustrated well the participation of leptin in the inflammatory response within the joints. In patients with RA, numerous studies have evaluated the concentrations of leptin in the bloodstream and/or the joint cavity, showing higher levels compared to control populations. Leptin has also been found to correlate with clinical or biological measurements of disease activity of RA. Conversely, the relationship between serum leptin and joint structural damage is less evident. Leptin may also promote the development of atherosclerosis in RA and may contribute to the cardiovascular consequences of the metabolic syndrome that coexists with RA. Indeed, leptin could be a link between inflammation, metabolic risk factors and cardiovascular diseases in RA. Finally, due to abnormal body composition phenotypes with an increased prevalence of obesity in RA, the therapeutic response to traditional DMARDs and/or biological agents may be attenuated. This review discusses the multiple interplays that have been described between leptin and the clinical, radiographic and therapeutic aspects of RA.