Metabolic syndrome in rheumatoid arthritis

Understanding the Role of the Complement System in Insulin Resistance and Metabolic Syndrome in Patients With Rheumatoid Arthritis

OBJECTIVE

The complement system has been associated with the etiopathogenesis of rheumatoid arthritis (RA). Insulin resistance (IR) and metabolic syndrome (MetS) are prevalent among patients with RA. The aim of this study was to explore the relationship between a comprehensive evaluation of the complement system and IR, as well as MetS, in patients with RA.

METHODS

A total of 339 nondiabetic patients with RA were recruited. Functional assays of the 3 complement pathways were assessed. Additionally, serum levels of the following individual components of the complement system were measured: C1q (classical); lectin (lectin); C2, C4, and C4b (classical lectin); factor D and properdin (alternative); C3 and C3a (common); C5, C5a, and C9 (terminal); as well as the factor I and C1 inhibitor regulators. IR and β cell function indices were calculated using the homeostatic model assessment. Criteria for MetS were applied. Multivariable linear regression analysis was performed to investigate the association between the complement system and IR in patients with RA.

RESULTS

Many elements of the upstream and common complement pathways, but not the functional tests of the 3 routes, correlated positively with higher levels of IR and β cell function. However, after multivariable adjustment for factors associated with IR, these relationships were lost. Conversely, the presence of MetS in patients with RA maintained a relationship with higher levels of C1q, C4, C3, properdin, and factor I after adjusting for confounders.

CONCLUSION

There is a positive correlation between the complement system and MetS among nondiabetic patients with RA. This association is independent of traditional IR factors.

Coffee consumption might be associated with lower potential risk and severity of metabolic syndrome: national health and nutrition examination survey 2003-2018

BACKGROUND

Metabolic syndrome (MetS) is a clinical syndrome characterized by multiple metabolic disorders and is a serious global health problem. The coffee effect, acting as one of the most prevalent beverages on metabolic syndrome, is debatable.

METHODS

We included patients from the National Health and Nutrition Examination Survey 2003-2018 and used a comprehensive evaluation called the MetS z-score to assess the severity of metabolic syndrome. The relationship between coffee, decaffeinated coffee, tea, and MetS z-scores was explored using a weighted linear regression. We also divided the participants into metabolic and non-metabolic syndrome groups according to the NCEP/ATP III criteria for the subgroup analysis.

RESULTS

A total of 14,504 participants were included in this study. The results demonstrated that drinking more than three cups of coffee daily was significantly linked to lower MetS z-scores (p < 0.001). Daily coffee consumption was also associated with lower BMI (p = 0.02), systolic blood pressure (p < 0.001), Homeostatic Model Assessment for Insulin Resistance (p < 0.001), and triglycerides (p < 0.001), while it was positively correlated with HDL-C (p = 0.001). Participants who consumed more than three cups of coffee daily had a lower MetS z-score in the MetS (p < 0.001) and non-MetS (p = 0.04) groups.

CONCLUSION

This research indicates that coffee consumption is linked to MetS severity. However, decaffeinated coffee and tea intake were unrelated to MetS severity.

The impacts of obesity in rheumatoid arthritis and insights into therapeutic purinergic modulation

Rheumatoid Arthritis (RA) is an autoimmune condition responsible for the impairment of synovia and joints, endangering the functionality of individuals and contributing to mortality. Currently, obesity is increasing worldwide, and recent studies have suggested an association between such condition and RA. In this sense, obese individuals present a lower capacity for achieving remission and present more intense symptoms of the disease, demonstrating a link between both disorders. Different studies aim to understand the possible connection between the conditions; however, few is known in this sense. Therefore, knowing that obesity can alter the activity of multiple body systems, this work's objective is to evaluate the main modifications caused by obesity, which can be linked to the pathophysiology of RA, highlighting as relevant topics obesity's negative impact triggering systemic inflammation, intestinal dysbiosis, endocrine disbalances. Furthermore, the relationship between oxidative stress and obesity also deserves to be highlighted, considering the influence of reactive oxygen species (ROS) accumulation in RA exacerbation. Additionally, many of those characteristics influenced by obesity, along with the classic peculiarities of RA pathophysiology, can also be associated with purinergic signaling. Hence, this work suggests possible connections between the purinergic system and RA, proposing potential therapeutic targets against RA to be studied.

Autoimmune polyendocrine syndromes associated with autoimmune rheumatic diseases

Autoimmune polyendocrine syndromes (APSs), also called autoimmune polyglandular syndromes, are a group of autoimmune diseases characterized by the co-occurrence of dysfunctions of several (at least two) endocrine glands. They develop under the influence of environmental factors in genetically predisposed people. Autoimmune polyendocrine syndromes may accompany autoimmune rheumatic diseases and worsen their course - APS-2 and APS-3 are the most common. The APS-2 includes the coexistence of, e.g. Hashimoto's disease, celiac disease and rheumatoid arthritis (RA). In APS-3, rheumatic diseases such as RA, systemic lupus erythematosus, and Sjögren's syndrome may coexist with Hashimoto's disease, type 1 diabetes and hypogonadism or other endocrinopathies. Undiagnosed endocrine diseases may be the reason for the intensification of metabolic disorders observed in the course of rheumatic diseases, cause the ineffectiveness of rheumatological treatment and also increase the frequency of bone fractures due to osteoporosis, cardiovascular complications and even miscarriages when coexistent, e.g. Hashimoto's disease with hypothyroiditis, which increases the risk of pregnancy loss. It is important to be able to conduct an extensive interview, paying attention to the symptoms of possible endocrinopathy as well as the features of other autoimmune disorders in the physical examination (e.g. vitiligo or darkening of the skin in Addison's disease). Depending on the history and physical examination, screening for various APSs is advised.

Dietary fiber intake associated with risk of rheumatoid arthritis among U.S. adults: NHANES 2010-2020

Rheumatoid arthritis (RA) is a prevalent inflammatory joint disease that imposes a significant medical burden and morbidity. Recent scientific evidence suggests that dietary components and patterns could be associated with RA risk. In this study, we aim to investigate the possible relationship between dietary fiber intake and RA risk. We included 15,114 participants from the 2010 to 2020 National Health and Nutrition Examination Survey database in our study. Participants aged 20 or above were categorized into those with and without RA. Univariate logistic regression analysis and multivariate regression models were used to test the association between dietary fiber intake, high-sensitivity C-reactive protein, and RA. Out of all the participants, 1053 were diagnosed with RA (6.97%). Multivariate logistic regression analysis indicated that fiber intake was negatively associated with high-sensitivity c-reactive protein (-0.09 [-0.18, -0.02]) and RA risk (0.99 [0.98, 0.99]). Furthermore, our sensitivity analysis suggested that individuals with higher fiber intake (>19.1 g/day) had a 25% lower risk of developing RA than those with lower fiber intake [0.75 (0.63, 0.88)]. Our findings suggest that higher dietary fiber intake is associated with a reduced risk of RA and may help reduce systemic inflammation, thereby potentially slowing down RA progression.

The Involvement of Glucose and Lipid Metabolism Alteration in Rheumatoid Arthritis and Its Clinical Implication

Obviously, immune cells like T cells and macrophages play a major role in rheumatoid arthritis (RA). On one hand, the breakdown of immune homeostasis directly induces systemic inflammation; on the other hand, these cells initiate and perpetuate synovitis and tissue damages through the interaction with fibroblast-like synoviocytes (FLS). In recent years, the pathological link between metabolic disorders and immune imbalance has received increasing attention. High energy demand of immune cells leads to the accumulation of metabolic byproducts and inflammatory mediators. They act on various metabolism-sensitive signal pathways as well as relevant transcription factors, such as HIF-1α, and STATs. These molecular events will impact RA-related effectors like circulating immune cells and joint-resident cells in return, allowing the continuous progression of systemic inflammation, arthritic manifestations, and life-threatening complications. In other words, metabolic complications are secondary pathological factors for the progression of RA. Therefore, the status of energy metabolism may be an important indicator to evaluate RA severity, and in-depth explorations of the mechanisms underlying the mystery of how RA-related metabolic disorders develop will provide useful clues to further clarify the etiology of RA, and inspire the discovery of new anti-rheumatic targets. This article reviews the latest research progress on the interactions between immune and metabolism systems in the context of RA. Great importance is attached to the changes in certain pathways controlling both immune and metabolism functions during RA progression.

Metabolic Abnormalities, Cardiovascular Disease, and Metabolic Syndrome in Adult Rheumatoid Arthritis Patients: Current Perspectives and Clinical Implications

AIM

Rheumatoid arthritis is a prevalent worldwide disease, associated with an increased risk of multiple metabolic abnormalities that generate a higher disease burden.

OBJECTIVE

To gather the available evidence on the epidemiology, pathophysiology, current perspectives, clinical implications and prognosis of metabolic abnormalities in patients with rheumatoid arthritis.

METHODS

This is a narrative literature review. Search was conducted in PubMed, OVID, and Taylor & Francis databases, using the following MeSH terms: "Arthritis Rheumatoid", "Metabolic Diseases", and "Metabolic Syndrome".

RESULTS

This study describes the main metabolic manifestations of rheumatoid arthritis. Research has recognized that rheumatoid arthritis and metabolic abnormalities share pathophysiological mechanisms with an additive effect that increases cardiovascular risk. In that context, appropriate antirheumatic treatment can also impact on cardiovascular risk.

CONCLUSION

There are metabolic abnormalities in rheumatoid arthritis patients that increase cardiovascular risk. Therefore, it is crucial to evaluate cardiovascular risk to provide appropriate comprehensive management to reduce morbidity and mortality in patients with this disease.

Effects of high fat diet-induced obesity on pathophysiology, immune cells, and therapeutic efficacy in systemic lupus erythematosus

Prior studies have suggested a strong link between obesity and autoimmune diseases. This study aimed to evaluate the effects of high fat diet (HFD)-induced obesity on the disease pathogenesis, immune cell infiltration, and therapeutic efficacy in systemic lupus erythematosus (SLE). Treatment with methylprednisolone significantly increased the survival in the control diet group, but not in the HFD group. An HFD significantly increased the incidence of severe proteinuria and glucose intolerance. Regardless of the diet, treatment with methylprednisolone significantly decreased the serum levels of anti-dsDNA antibodies, IL-2, IL-10, and interferon γ-induced protein 10 (IP-10), and improved the renal pathology scores. Treatment with methylprednisolone significantly lowered the serum levels of IL-6, MCP-1, and TNF-α in the control diet group, but not in the HFD group. HFD significantly increased the proportions of CD45⁺ and M1 cells and significantly decreased the proportion of M2 cells in white adipose tissue; methylprednisolone treatment significantly rescued this effect. In the HFD group, methylprednisolone treatment significantly decreased the M1:M2 and increased the Foxp3⁺:RORγt⁺ cell in the spleen compared with the untreated group. These data improve our understanding of the effect of HFD on the therapeutic efficacy of corticosteroids in SLE treatment, which could have clinical implications.

Effects of One-Year Tofacitinib Therapy on Lipids and Adipokines in Association with Vascular Pathophysiology in Rheumatoid Arthritis

Background: Cardiovascular (CV) morbidity, mortality and metabolic syndrome are associated with rheumatoid arthritis (RA). A recent trial has suggested increased risk of major CV events (MACE) upon the Janus kinase (JAK) inhibitor tofacitinib compared with anti-tumor necrosis factor α (TNF-α) therapy. In our study, we evaluated lipids and other metabolic markers in relation to vascular function and clinical markers in RA patients undergoing one-year tofacitinib therapy. Patients and methods: Thirty RA patients treated with either 5 mg or 10 mg bid tofacitinib were included in a 12-month follow-up study. Various lipids, paraoxonase (PON1), myeloperoxidase (MPO), thrombospondin-1 (TSP-1) and adipokine levels, such as adiponectin, leptin, resistin, adipsin and chemerin were determined. In order to assess flow-mediated vasodilation (FMD), common carotid intima-media thickness (IMT) and arterial pulse-wave velocity (PWV) ultrasonography were performed. Assessments were carried out at baseline, and 6 and 12 months after initiating treatment. Results: One-year tofacitinib therapy significantly increased TC, HDL, LDL, APOA, APOB, leptin, adipsin and TSP-1, while significantly decreasing Lp(a), chemerin, PON1 and MPO levels. TG, lipid indices (TC/HDL and LDL/HDL), adiponectin and resistin showed no significant changes. Numerous associations were found between lipids, adipokines, clinical markers and IMT, FMD and PWV (p < 0.05). Regression analysis suggested, among others, association of BMI with CRP and PWV (p < 0.05). Adipokines variably correlated with age, BMI, CRP, CCP, FMD, IMT and PWV, while MPO, PON1 and TSP-1 variably correlated with age, disease duration, BMI, RF and PWV (p < 0.05). Conclusions: JAK inhibition by tofacitinib exerts balanced effects on lipids and other metabolic markers in RA. Various correlations may exist between metabolic, clinical parameters and vascular pathophysiology during tofacitinib treatment. Complex assessment of lipids, metabolic factors together with clinical parameters and vascular pathophysiology may be utilized in clinical practice to determine and monitor the CV status of patients in relation with clinical response to JAK inhibition.

Prevalence of Metabolic Syndrome in Patients With Rheumatoid Arthritis: An Updated Systematic Review and Meta-Analysis

Introduction

Rheumatoid arthritis (RA) due to systemic inflammation and insulin resistance increases the risk of cardiovascular disease and reduces life expectancy. In order to develop cardiac death prevention strategies, it is necessary to estimate the prevalence of metabolic syndrome (MetS) in these patients.

Methods

This systematic review and meta-analysis was performed to estimate the prevalence of MetS among patients with RA. International databases (i.e., Scopus, PubMed, Web of Science, and Google Scholar) were searched during the period of October 1 and October 10, 20121. Heterogeneity among the included studies was assessed through the Cochrane Q test statistics and I² test. Finally, a random-effects meta-analysis model was computed to estimate the pooled prevalence of MetS.

Results

Sixty-one articles with 96 groups and a sample size of 13,644 people were analyzed. The pooled prevalence of MetS was 32% (95% CI: 29.6–34.4). The highest prevalence of MetS is related to studies conducted in Asia (32.7%, 95% CI: 29–36.3) and Europe (32.7%, 95% CI: 27.5.37.9) and the lowest Prevalence was also related to studies conducted in Africa (28%, 95% CI: 28.8–32.2). The prevalence of MetS in men was 33% (95% CI: 26–39) and 34% (95% CI: 29–40) in women. Findings by diagnostic criteria showed that the highest and lowest prevalence of MetS was related to ATP III (37.5%, 95% CI: 30.9–44.2) and EGIR (14.4%, 95% CI: 10.5–18.5), respectively.

Conclusions

MetS is highly prevalent in patients with RA and identification of high-risk patients is necessary to prevent cardiovascular mortality.

Changes of Metabolic Biomarker Levels upon One-Year Anti-TNF-α Therapy in Rheumatoid Arthritis and Ankylosing Spondylitis: Associations with Vascular Pathophysiology

Background: Cardiovascular (CV) morbidity, mortality, and metabolic syndrome are associated with rheumatoid arthritis (RA) and ankylosing spondylitis (AS). Here, lipids and other metabolic markers in relation to vascular function and clinical markers were evaluated in RA and AS patients undergoing one-year anti-TNF therapy. Patients and methods: Fifty-three patients including 36 RA patients treated with either etanercept (ETN) or certolizumab pegol (CZP) and 17 AS patients treated with ETN were included in a 12-month follow-up study. Various lipids, paraoxonase (PON) and arylesterase (ARE) activities, myeloperoxidase (MPO) and adipokine levels were determined overtime. Ultrasonography was performed to determine flow-mediated vasodilation (FMD), common carotid intima-media thickness (ccIMT), and arterial pulse-wave velocity (PWV) in all patients. All assessments were performed at baseline and 6 and 12 months after treatment initiation. Results: Anti-TNF therapy decreased ARE activity, MPO, adiponectin, and chemerin levels after 12 months (p < 0.05). Lipids, PON activity, and leptin remained unchanged. Regression analyses suggested variable associations of IMT, PWV, and FMD with ARE, MPO, leptin, and lipids (p < 0.05). On the other hand, these metabolic parameters were significantly associated with disease duration, CV history, CRP, obesity, PWV, and IMT (p < 0.05). One-year anti-TNF treatment together with baseline leptin (p = 0.039) or CRP (p = 0.016) levels determined 12 months of lipid changes overtime. TNF inhibition together with baseline disease activity determined ARE activity changes (p = 0.046). Anti-TNF therapy and baseline chemerin levels determined IMT changes overtime (p = 0.003). Conclusions: Assessment of various metabolic parameters together with disease activity, CRP, and ultrasound-based techniques may exert additional value in determining CV burden and in monitoring the effects of biologics on preclinical vascular pathophysiology.

Emerging role of leptin in joint inflammation and destruction

Rheumatoid arthritis (RA) is an autoimmune disease characterized by tumor-like hyperplasia and inflammation of the synovium, which causes synovial cell invasion into the bone and cartilage. In RA pathogenesis, various molecules in effector cells (i.e., immune cells and mesenchymal cells) are dysregulated by genetic and environmental factors. Consistent with the early stages of RA, these pathogenic cells cooperate and activate each other directly by cell-to-cell contact or indirectly via humoral factors. Recently, growing evidence has revealed essential role of adipokines, which are multifunctional signal transduction molecules, in the immune system. In this review, we summarize the current understanding of the cross-talk between leptin, one of the most well-known and best-characterized adipokines, and osteoimmunology. Furthermore, we discuss the contribution of leptin to the pathogenesis of RA and its potential mechanisms.

Potential relation of cardiovascular risk factors to disease activity in patients with axial spondyloarthritis

Background:

Axial spondyloarthritis (axSpA) patients are known to have a higher prevalence of several comorbidities, including, among others, an increased risk of atherosclerosis, hypertension, dyslipidemia, and diabetes. The purpose of the present study was to determine whether the sum of traditional cardiovascular (CV) risk factors is related to disease characteristics, such as disease activity, in patients with axSpA.

Methods:

A cross-sectional study that encompassed 804 patients with axSpA was conducted. Patients were assessed for the presence of five traditional CV risk factors (diabetes mellitus, dyslipidemia, hypertension, obesity, and smoking status), and disease activity measurements. A multivariable regression analysis was performed to evaluate whether the number of classic CV risk factors was independently associated with specific features of the disease, to include disease activity.

Results:

A multivariable analysis showed that Ankylosing Spondylitis Disease Activity Score–C reactive protein (ASDAS-CRP) activity score was significantly higher in patients with 1 [beta coefficient 0.3 (95% confidence interval (CI) 0.1–0.5), p = 0.001] and ⩾2 [beta coefficient 0.5 (95% CI 0.3–0.7), p = 0.000] CV risk factors compared with those without CV risk factors. Similarly, patients with 1 [OR 2.00 (95%CI 0.99–4.02), p = 0.053] and ⩾2 [OR 3.39 (95%CI 1.82–6.31), p = 0.000] CV risk factors had a higher odds ratio for the presence of high disease activity compared with the zero CV category. The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) activity score was significantly associated with the number of CV risk factors, being higher in patients with more CV risk factors. These relationships showed a CV risk factor-dependent effect being beta coefficients and ORs higher for the effect of ⩾2 over 1 CV risk factor.

Conclusion:

Among patients with axSpA, as the number of traditional CV risk factors increased, disease activity similarly increases in an independent manner.

Early-life famine exposure and rheumatoid arthritis in Chinese adult populations: a retrospective cohort study

OBJECTIVE

This study aimed to explore the association between famine exposure in early life and the odds of rheumatoid arthritis (RA) in adulthood.

DESIGN

A population-based retrospective cohort study.

SETTING

China.

PARTICIPANTS

A total of 111 706 participants (1775 with RA) born from 1956 to 1964 were selected from the baseline survey of a large cohort in China.

PRIMARY AND SECONDARY OUTCOME MEASURES

Four famine exposure groups were generated based on dates of birth, namely prenatal-exposed, infant-exposed, preschool-exposed and non-exposed groups. Logistic regressions were used to explore the association between famine exposure and self-reported RA in adulthood, adjusting for sex, region, monthly income, highest education, alcohol consumption, tobacco use, body mass index (BMI) and metabolic equivalent tasks. Analyses were also performed with stratification for sex (female or male), residing region (urban or rural), famine severity (severe or non-severe) and BMI (≥24 or <24).

RESULTS

The study included 1775 (1.59%) RA cases and 109 931 (98.41%) non-RA controls. Among them, 22 413 (20.06%) were prenatal-exposed, 14 899 (13.34%) were infant-exposed and 34 356 (30.76%) were preschool-exposed. Prenatal exposure to famine was not associated with onset of RA in adulthood. Infant-exposed group and preschool-exposed group had significantly elevated odds of getting RA compared with non-exposed group (infant-exposed: OR=1.44, 95% CI 1.24 to 1.67; preschool-exposed: OR=1.38, 95% CI 1.22 to 1.57, p<0.001), and the relationship was stronger among women, urban residents and participants with BMI ≥24. Similar results were additionally observed when an age-balanced control group was used.

CONCLUSIONS

Exposure to the Great Chinese Famine in early life after birth especially in infancy may be associated with a higher risk of RA in adulthood. Strengthening early-life nutrition could be an implication to prevent future RA.

Lipid metabolism in cartilage and its diseases: a concise review of the research progress

The homeostasis of the vertebrate body depends on anabolic and catabolic activities that are closely linked the inside and outside of the cell. Lipid metabolism plays an essential role in these metabolic activities. Although a large amount of evidence shows that normal lipid metabolism guarantees the conventional physiological activities of organs in the vertebrate body and that abnormal lipid metabolism plays an important role in the occurrence and deterioration of cardiovascular-related diseases, such as obesity, atherosclerosis, and type II diabetes, little is known about the role of lipid metabolism in cartilage and its diseases. This review aims to summarize the latest advances about the function of lipid metabolism in cartilage and its diseases including osteoarthritis, rheumatoid arthritis, and cartilage tumors. With the gradual in-depth understanding of lipid metabolism in cartilage, treatment methods could be explored to focus on this metabolic process in various cartilage diseases.

The troubling liaison between cancer and metabolic syndrome in chronic inflammatory rheumatic diseases

Background

Several studies on community populations found that metabolic syndrome (MetS) is associated with higher risk for total incident cancer with a predisposition for specific types of cancer. These findings have never been analyzed in patients with chronic inflammatory rheumatic and musculoskeletal diseases (RMD). We assessed prevalence/incidence and factors related to the development of cancer in a large cohort of these patients and evaluate whether MetS and its components were associated with cancer independent of traditional markers of inflammation.

Methods

Between March 2014 and April 2016, 474 patients with RMD involved in a cardiovascular primary prevention program were consecutively recruited into this ambispective (combination of retrospective/prospective) study. They underwent clinical, laboratory, and echocardiographic evaluations. MetS was diagnosed according to the ATPIII criteria.

Results

Duration of follow-up was 42 [18–60] months. Patients with a diagnosis of cancer (made before recruitment or during follow-up) were 46 (9.7%). Cancer was diagnosed in 22/76 patients (29%) with MetS and in 24/398 patients (6%, p < 0.001) without MetS; nearly two thirds of malignancies belonged to those traditionally related to MetS. MetS was the strongest cancer risk factor. Cancer was positively associated with the number of MetS components identified in each patient. Beyond MetS, cancer was associated to older age and increased inflammatory disease activity; this information allowed to build a simple performance indicator highly sensitive for cancer development.

Conclusion

In light of our results, an increasingly accurate assessment of MetS would be required in patients with RMD as potential measure of clinical outcomes including the risk of cancer.

Body Mass Index and Disease Activity in Chronic Inflammatory Rheumatic Diseases: Results of the Cardiovascular in Rheumatology (Carma) Project

OBJECTIVE

Since obesity has been associated with a higher inflammatory burden and worse response to therapy in patients with chronic inflammatory rheumatic diseases (CIRD), we aimed to confirm the potential association between body mass index (BMI) and disease activity in a large series of patients with CIRDs included in the Spanish CARdiovascular in rheuMAtology (CARMA) registry.

METHODS

Baseline data analysis of patients included from the CARMA project, a 10-year prospective study of patients with rheumatoid arthritis (RA), ankylosing spondylitis (AS), and psoriatic arthritis (PsA) attending outpatient rheumatology clinics from 67 Spanish hospitals. Obesity was defined when BMI (kg/m²) was >30 according to the WHO criteria. Scores used to evaluate disease activity were Disease Activity Score of 28 joints (DAS28) in RA, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) in AS, and modified DAS for PsA.

RESULTS

Data from 2234 patients (775 RA, 738 AS, and 721 PsA) were assessed. The mean ± SD BMI at the baseline visit were: 26.9 ± 4.8 in RA, 27.4 ± 4.4 in AS, and 28.2 ± 4.7 in PsA. A positive association between BMI and disease activity in patients with RA (β = 0.029; 95%CI (0.01- 0.05); p = 0.007) and PsA (β = 0.036; 95%CI (0.015-0.058); p = 0.001) but not in those with AS (β = 0.001; 95%CI (-0.03-0.03); p = 0.926) was found. Disease activity was associated with female sex and rheumatoid factor in RA and with Psoriasis Area Severity Index and enthesitis in PsA.

CONCLUSIONS

BMI is associated with disease activity in RA and PsA, but not in AS. Given that obesity is a potentially modifiable factor, adequate control of body weight can improve the outcome of patients with CIRD and, therefore, weight control should be included in the management strategy of these patients.

Metabolic syndrome in rheumatoid arthritis patients: Relationship among its clinical components

BACKGROUND

Metabolic syndrome (MetS) prevalence in rheumatoid arthritis (RA) patients is known to vary considerably across the world. This study aimed to determine the prevalence of MetS in RA patients from western Mexico and to analyze the interrelation of the MetS components with the clinical variables of RA.

METHODS

This case-control study included 216 RA patients and 260 control subjects (CS). MetS prevalence was determined according to the NCEP/ATP III and the Latin American Consensus of the Latin American Diabetes Association (ALAD) criteria.

RESULTS

MetS was observed in 30.6% RA patients and 33.3% of controls (p > 0.05) according to NCEP/ATP III and 28.7% in RA patients and 31.1% for controls using ALAD criteria. Total cholesterol, LDL-C, and Castelli's I-II indexes were lower in RA (p < 0.001) than in CS. The RA patients with MetS had more swollen joints than those without MetS (p = 0.018). In RA patients with MetS, DAS-28 score correlated with smoking index (rho = 0.4601, p = 0.0004) and VLDL-C (rho = 0.3108, p = 0.0056); similarly, rheumatoid factor (RF) correlated with age (rho = 0.2031, p = 0.0027), smoking index (rho = 0.3404, p < 0.0001), triglycerides (rho = 0.1958, p = 0.0039), and VLDL-C (rho = 0.1761, p = 0.0162).

CONCLUSIONS

The MetS prevalence in RA patients from western Mexico is not higher than controls; however, in RA patients with MetS, some inflammatory markers are associated with MetS components; thus, the control of MetS in RA could be beneficial to regulate disease activity.

Correlation between sarcopenia and nailfold microcirculation, serum 25-hydroxycholecalciferol (vitamin D3) and IL-17 levels in female patients with rheumatoid arthritis

AIMS

To investigate the correlation between sarcopenia and nailfold microcirculation and serum 25-hydroxycholecalciferol [25 (OH) D3] (instead of 25-hydroxyvitamin D) and IL-17 levels in female rheumatoid arthritis (RA) patients.

METHODS

130 female rheumatoid arthritis (RA) patients and 80 healthy controls were tested. Nailfold capillaroscopic scores (NFCS) were measured. Bioimpedance analysis (BIA) was used to measure skeletal muscle mass. Enzyme-linked immunosorbant assay (ELISA) was used to detect the levels of IL-17, IL-6 and TNF-α. Serum 25 (OH) D3 concentration was determined by photochemical immunoassay. The correlation was analyzed by Pearson's correlation, and the influencing factors were analyzed by binary logistic regression.

RESULTS

(1) Compared with the control group, NFCS and serum IL-17 levels were higher in the RA group, while the serum 25 (OH) D3 and skeletal mass index (SMI) were lower. (2) Pearson correlation analysis found: SMI was positively correlated with 25 (OH) D3 (r=0.515, P<0.001), SMI was negatively correlated with IL-17 (r=-0.468, P<0.001), SMI was negatively correlated with NFS (r = -0.229, P=0.009); (3) Logistic regression analysis: serum 25 (OH) D3 was a protective factor for sarcopenia (OR=0.392, P=0.016); IL-17, C-reactive protein, and NFS were risk factors for sarcopenia (OR=1.516, P=0.049; OR=1.469, P=0.045; OR=3.497, P=0.002).

CONCLUSION

Secondary sarcopenia in RA is common and is closely related to microcirculation abnormalities. Increased NFCS is a risk factor for sarcopenia. Decreased serum 25 (OH) D3 levels and increased IL-17 are also risk factors for sarcopenia, but the mechanisms involved in sarcopenia and microcirculation abnormalities need further investigation.

Ideal food pyramid for patients with rheumatoid arthritis: A narrative review

Emerging literature suggests that diet plays an important modulatory role in rheumatoid arthritis (RA) because diet is an environmental factor that affects inflammation, antigen presentation, antioxidant defense mechanisms and gut microbiota. Patients with RA frequently ask their doctors about which diets to follow, and even in the absence of advice from their physicians, many patients are undertaking various dietary interventions. Given this background, the aim of this review is to evaluate the evidence to date regarding the ideal dietary approach for management of RA in order to reduce the counteracting inflammation, and to construct a food pyramid for patients with RA. The pyramid shows that carbohydrates should be consumed every day (3 portions of whole grains, preferably gluten free), together with fruits and vegetables (5 portions; among which fruit, berries and citrus fruit are to be preferred, and among the vegetables, green leafy ones.), light yogurt (125 ml), skim milk (200 ml), 1 glass (125 ml) of wine and extra virgin olive oil; weekly, fish (3 portions), white meat (3 portions), legumes (2 portions) eggs (2 portions), seasoned cheeses (2 portions), and red or processed meats (once a week). At the top of the pyramid, there are two pennants: one green means that subjects with RA need some personalized supplementation (vitamin D and omega 3) and one red means that there are some foods that are banned (salt and sugar). The food pyramid allows patients to easily figure out what to eat.

Insulin resistance in non-diabetes patients with spondyloarthritis

Objectives: Insulin resistance (IR) constitutes a major underlying abnormality driving cardiovascular disease in the general population and has been linked to inflammatory diseases. In this study, we aimed to determine the prevalence of IR in patients with spondyloarthritis (SpA) and whether IR can be explained by disease-related features in such cases. Method: The study included 577 subjects: 306 patients diagnosed with SpA according to Assessment of SpondyloArthritis international Society criteria and 271 controls. Insulin and C-peptide serum levels, IR and β-cell function (%B) indices by homoeostatic model assessment (HOMA2), and lipid profiles were assessed in patients and controls. A multivariable regression analysis was performed to evaluate the differences in IR indices between patients and controls and to determine how IR is associated with disease-related characteristics in SpA patients. Results: HOMA2-%B and HOMA2-IR scores, both calculated with insulin or C-peptide, had significantly higher values in SpA patients compared to controls in multivariable analysis adjusted for age, gender, traditional IR-related factors, and glucocorticoid intake. Disease activity, functional status, and metrological SpA indices were positively related to IR, but only in univariable analysis. Disease duration and positivity for human leucocyte antigen-B27 were independently associated with a higher HOMA2-%B after multivariable analysis. Conclusion: Patients with SpA have an increased IR compared to controls. SpA disease-related data are independently associated with β-cell dysfunction.

Metabolic Syndrome and Atherogenic Indices in Rheumatoid Arthritis and their Relationship with Disease Activity: A Hospital-based Study from Northeast India

Background and Objective

Metabolic syndrome (MetS), a constellation of metabolic abnormalities including hypertension, obesity, glucose intolerance, and dyslipidemia, is highly prevalent in patients with rheumatoid arthritis (RA). Our aim was to assess the magnitude of MetS and its determinants in RA patients and to evaluate different atherogenic indices that are reflective of the risk for future cardiovascular disease.

Patients and Methods

The study was conducted on 104 RA patients and 103 age- and sex-matched healthy controls. The frequency of MetS was assessed using the guidelines recommended for Asian Indians.

Results

A total of 104 RA patients participated with majority being females (85.6%), with a mean age of 43.82 ± 13.32 years. The frequency of MetS in patients with RA (36.5%) was significantly higher than in controls (15.5%). The atherogenic indices were found to be significantly higher in RA patients than controls (P < 0.01). On logistic regression, disease activity score (DAS28) scale for 28 joints and disease duration remained significant independent predictors of the presence of MetS in RA patients (P < 0.01 and 0.05, respectively).

Conclusions

RA is a kind of chronic disease of long course, and MetS and atherogenic indices are often concomitant in these patients. The study showed that the frequency of MetS was higher in patients with RA than in controls, and that DAS28 and disease duration remained significant independent predictors of the presence of MetS in RA patients.

Tocilizumab Increases Body Weight and Serum Adipokine Levels in Patients with Rheumatoid Arthritis Independently of Their Treatment Response: a Retrospective Cohort Study

BACKGROUND

Causes of weight change after tocilizumab treatment are unclear. We aimed to investigate the effects of tocilizumab treatment on body weight and serum adipokine levels in patients with rheumatoid arthritis (RA).

METHODS

In this retrospective cohort study, we evaluated weight changes in patients with RA who received methotrexate (Cohort I) or tocilizumab with methotrexate (Cohorts II and III) for 24 weeks. Adipokine concentrations at baseline and 24 weeks were analyzed in Cohorts I and III. Cohorts I and II received tocilizumab therapy for an additional 48 weeks, during which weight changes were monitored (24-72 weeks).

RESULTS

No significant weight change occurred after 24 weeks of methotrexate treatment (mean difference, -0.2 kg; P = 0.630), but was observed after 24 weeks of tocilizumab treatment (mean difference, +0.9 kg; P = 0.010). Weight changed regardless of the treatment response in both treatment groups. The leptin-adiponectin ratio (P = 0.015) and levels of adiponectin (P < 0.001), leptin (P < 0.001), and resistin (P = 0.003) increased significantly after 24 weeks of tocilizumab, but not methotrexate treatment. After 24, 48 and 72 weeks of tocilizumab treatment in Cohort II, mean (95% confidence interval [CI]) weight changes from baseline were +0.7 (0.0-1.4), +1.2 (0.4-2.0) and +1.1 (0.2-2.0) kg, respectively, and mean (95% CI) percent weight changes from baseline were +1.3% (0.1%-2.6%), +2.2% (0.7%-3.6%), and +2.0% (0.4%-3.7%) at 24, 48, and 72 weeks, respectively.

CONCLUSION

Weight and the leptin-adiponectin ratio increased after tocilizumab treatment. Given that cardiovascular (CV) risk factors may deteriorate in patients with RA who receive tocilizumab, further studies are required to determine the effects of weight gain on CV outcomes in these patients.

Sex and Cardiovascular Involvement in Inflammatory Joint Diseases

The term inflammatory joint disease (IJD) encompasses a group of chronic conditions with predominant joint involvement. They share an increased risk of cardiovascular (CV) complications. However, the implication of the sex in the risk of CV disease in IJD has not been specifically addressed. The aim of this work is to assess the influence of sex on the clinical expression of CV manifestations associated to IJD. With this objective, an update of the current knowledge of the sex influence on CV disease in patients with IJD was conducted. A PubMed database search of the most relevant literature on this topic was performed mainly based on studies published in English over the last 10 years. Although most studies on IJD were not specifically designed to address sex differences regarding CV complications, it seems that men with rheumatoid arthritis (RA) are at higher risk of pericarditis, ischemic heart disease, heart failure (HF) with reduced ejection fraction (EF), and CV mortality than women with RA. In contrast, HF with preserved EF and diastolic dysfunction is more frequent in women with RA. Men with ankylosing spondylitis present more frequently disorders of the conduction system and aortic valvulopathy than women. A limited number of studies addressed CV differences according to sex in psoriatic arthritis. Although there are some differences according to sex in the clinical expression of CV complications in patients with IJD, much research is still needed to better identify the implication of sex in the risk of CV disease in these patients.

Changes in serum adipokines profile and insulin resistance in patients with rheumatoid arthritis treated with anti-TNF-α

Background: Rheumatoid arthritis (RA) is a chronic inflammatory joint disease characterized by an altered glucose and lipid metabolism. Tumor necrosis factor alpha (TNF-α) is involved in the pathogenesis of both RA and metabolic syndrome. This study evaluated the effects of anti-TNF-α agents (adalimumab, etanercept, infliximab) on lipid and glucose metabolism in patients with RA.Methods: A total of 33 RA, biological therapy-naive patients were recruited. Changes in Disease Activity, Body Mass Index, resistin, leptin and adiponectin serum levels, lipid profile, atherogenic index, insulin sensitivity index, and insulin resistance index were evaluated at baseline and after anti-TNF-α treatments.Results: Anti-TNF-α treatment was effective in reducing disease activity. An inverse relationship between disease activity and adiponectin levels was found, whereas leptin and resistin levels directly correlated with disease activity. TNF-α therapy significantly reduced leptin, resistin, and increased adiponectin. TNF-α inhibition resulted in a reduction of atherogenic index and insulin resistance index while increased insulin sensitivity index.Conclusion: Anti-TNF-α agents could have a crucial role in modifying the impact of lipid profile and glucose levels dysregulation in RA patients. TNF-α inhibition may be a potential strategy for the prevention of metabolic syndrome and could play a role in the reduction of cardiovascular risk in RA.

Psoriatic arthritis: From pathogenesis to pharmacologic management

The pathogenesis of psoriatic arthritis (PSA) is still a matter of debate. A favourable genetic background is interwoven with environmental triggering factors in a complex network. Shared antigens and the recirculation of immune cells may account for the clinical manifestations, involving both cutaneous and articular sites. A favourable genetic background has been demonstrated in many genomic and proteomic studies, being associated to polymorphic variants of the genes coding for Major Histocompatibility Complex I and cytokine pathways. In genetic-predisposed individuals, triggering factors, like infections, dysbiosis or mechanic stress may promote the development of the disease. The subsequent activation of the innate and adaptive immune system, following the stimulation of Toll-like Receptors, culminates in the expansion of dendritic cells, macrophages, CD4+ and CD8+ T cells, neutrophils, monocytes, Natural Killer lymphocytes and other cells with the final inflammation and damage of skin, joint and enthesis. Particularly, the activation of CD4+ T helper 17 lymphocytes represents a crucial point in the pathogenesis of the disease. The participation of the visceral adipose tissue may amplify the inflammatory process by means of the synthesis of pro-inflammatory adipokines. Current therapeutic algorithms address the variety of clinical manifestations with a tailored strategy aiming to achieve the best control of the symptoms with minimal side effects. Conventional immunosuppressive drugs, biologic agents and synthetic small molecules offer different attack routes and may be chosen individually or in combination according to the phenotype of the disease.

In the absence of specific advice, what do patients eat and avoid? Results from a community based diet study in patients suffering from rheumatoid arthritis (RA) with a focus on potassium

Rheumatoid arthritis (RA) is a painful disabling difficult to treat disease. Clinicians and guidelines invariably focus on drugs. Diet is important but lacks robust data. We carried out a comprehensive analytical study in Indian (Asian) patients.

METHODS

141 consenting symptomatic chronic RA patients [mean age 46 years) center and 165 unrelated healthy control subjects (mean age 36 years) completed a a-priori validated food frequency questionnaire in a cross-sectional non-random design study under the supervision of a nutritionist. All patients were under standard rheumatology care. A 3 day retrospective recall record captured dietary data for all subjects. National Indian guidelines were adopted for diet analytics. Standard statistical analysis was carried out; significant p < 0.05.

RESULTS

Daily diet was found to be significantly deficient in calories and consumption of proteins, calcium and potassium when compared to healthy subjects. It was also inadequate for several nutrients when compacted to recommended daily allowance. The proportion of carbohydrates (65%), proteins (15%) and fat (25%) in daily diet was consistent with Indian standards (healthy). Women patients reported higher deficiency. 44% patients consumed vegetarian diet and showed lesser pain and better function compared to non-vegetarians (not significant). 44% patients reported dietary restriction; higher swollen joint counts in patients following any dietary restriction (p = 0.01) or Ayurveda (ancient Indian medicinal system) advise (p = 0.01) or consuming night shade vegetables (p = 0.002).

CONCLUSION

Dietary inadequacy and in particular for protein and potassium was identified in patients of RA. Any form of dietary restriction did not seem to improve RA. Specific dietary needs of RA patients and in particular impact of potassium deficiency needs further research.

Relationship Between Insulin Sensitivity and β-Cell Secretion in Nondiabetic Subjects with Rheumatoid Arthritis

OBJECTIVE

In nondiabetic healthy individuals, insulin secretion and sensitivity are linked by a negative feedback loop characterized by a hyperbolic function. We aimed to study the association of traditional insulin resistance (IR) factors with insulin secretion and sensitivity, and to determine whether the hyperbolic equilibrium of this relation is preserved in patients with rheumatoid arthritis (RA).

METHODS

This was a cross-sectional study encompassing 361 nondiabetic individuals: 151 with RA and 210 controls. Insulin, C-peptide, and IR indices by homeostatic model (HOMA2) were assessed. A multivariable analysis was performed to evaluate the differences in the correlation of traditional IR-related factors with glucose homeostasis molecules, as well as IR indices between patients and controls. Nonlinear regression analysis was used to assess the hyperbolic relation of insulin sensitivity and secretion.

RESULTS

HOMA2-IR indices were higher in patients with RA than controls. Hepatic insulin extraction, as assessed by the insulin:C-peptide molar ratio, was lower in patients with RA after multivariable analysis (0.08 ± 0.02 vs 0.14 ± 0.07, p < 0.001). Traditional IR-related factors showed significantly lower adjusted correlation coefficients with IR indices in patients with RA. The association between insulin sensitivity and secretion showed a different hyperbolic relation in patients with RA: the variability explained by the curve was lower in RA (nonlinear r² = 0.845 vs r² = 0.928, p = 0.001) and β coefficients (-0.74, 95% CI -0.77 to -0.70 vs -1.09, 95% CI -1.17 to -1.02, ng/ml, p < 0.001) were different in RA.

CONCLUSION

The traditional factors associated with IR in healthy individuals are less related to IR in patients with RA. Insulin sensitivity and secretion yield a different hyperbolic equilibrium in RA.

Are we really what we eat? Nutrition and its role in the onset of rheumatoid arthritis

Accumulating research evidence suggests that individual dietary factors and dietary patterns might be implicated in the risk of development of rheumatoid arthritis (RA). This narrative review aims to present this evidence and provide nutritional recommendations for reducing RA risk in susceptible individuals. Overall, a 'Western' type diet rich in energy intake, total and saturated fat, an unbalanced ratio of n-3 to n-6 fatty acids, high in refined carbohydrates and sugar and low in fiber and antioxidants might increase the risk of RA both directly through increasing inflammation and indirectly through increasing insulin resistance and obesity, with the latter being a known risk factor for RA. On the contrary, consumption of long-chain omega-3 polyunsaturated fatty acids, derived from fish and fish oil, is associated with a reduced risk of RA probably due to their anti-inflammatory properties. The Mediterranean diet (MD), rich in plant-based foods such as wholegrains, legumes, fruit, vegetables, extra-virgin olive oil and low in red meat consumption, might have the potential to reduce the risk of RA. Based on current research evidence, it is suggested that adherence to the MD enhanced with an increased consumption of fatty fish, reduced consumption of sugar-sweetened drinks and maintenance of a normal body weight, contributes to reducing the risk of RA. Further research on RA susceptibility will allow for more specific dietary recommendations to be made.

Insulin resistance in hidradenitis suppurativa: a case-control study

BACKGROUND

The association between chronic inflammatory diseases, such as rheumatoid arthritis and psoriasis, and insulin resistance (IR) has been well established. Hidradenitis suppurativa (HS) is a chronic inflammatory cutaneous disease that affects the apocrine gland-bearing areas of the body.

OBJECTIVE

We aimed to determine the prevalence of IR in patients with HS.

METHODS

This cross-sectional, case-control study enrolled 137 subjects, 76 patients with HS and 61 age- and gender-matched controls. Demographic data, clinical examination of HS patients, anthropometric measures, cardiovascular risk factors and laboratory studies were recorded. The homeostasis model assessment of IR (HOMA-IR) was calculated in all participants by measuring fasting plasma glucose and insulin levels.

RESULTS

The median (IQR) HOMA-IR value in HS patients was significantly higher [2.0 (1.0-3.6)] than in controls [1.5 (0.9-2.3)] (P = 0.01). The prevalence of IR was significantly higher in cases (43.4%) compared with controls (16.4%) (P = 0.001). In the linear regression multivariable analysis after adjusting for age, sex and body mass index (BMI), HS remained as a significant factor for a higher HOMA-IR [2.51 (0.18) vs 1.92(0.21); P = 0.04]. The HOMA-IR value and the prevalence of IR did not differ significantly among HS patients grouped by severity of the disease.

CONCLUSION

Our results show an increased frequency of IR in HS. Thus, we suggest HS patients to be evaluated for IR and managed accordingly.

Vitamin D Status, Disease Activity, and Endothelial Dysfunction in Early Rheumatoid Arthritis Patients

Cardiovascular diseases represent important complications in rheumatoid arthritis (RA) patients, generated by an accelerated atherosclerosis. The aim of this study is represented by the assessment of the correlations between serum levels of vitamin D, disease activity, and endothelial dysfunction in patients with early RA. Material and Methods. The study was performed on a group of 35 patients with early RA and 35 healthy subjects matched for age and gender, as controls. In all studied subjects, the following were determined: inflammatory markers, insulin resistance, vitamin D levels, and endothelial dysfunction. Statistical analysis were performed using the Student's t-test and the Pearson's test. p values of less than 0.05 were considered statistically significant. Results. The group of patients with RA patients presented inflammation, low levels of vitamin D, elevated insulin resistance, and reduced flow-mediated vasodilation, statistically significant compared to the control group (p < 0.00001). Significant inverse correlations between the levels of 25(OH) vitamin D and DAS28, respective insulin resistance, and significant positive correlation between 25(OH) vitamin D and endothelial function were demonstrated. Conclusion. In early RA patients with moderate and high disease activity, low serum levels of vitamin D were associated with disease activity, increased insulin resistance, and endothelial dysfunction.

Incretins in patients with rheumatoid arthritis

Background

The precise mechanism linking systemic inflammation with insulin resistance (IR) in rheumatoid arthritis (RA) remains elusive. In the present study, we determined whether the incretin-insulin axis and incretin effect are disrupted in patients with RA and if they are related to the IR found in these patients.

Methods

We conducted a cross-sectional study that encompassed 361 subjects without diabetes, 151 patients with RA, and 210 sex-matched control subjects. Insulin, C-peptide, glucagon-like peptide-1 (GLP-1), gastric inhibitory polypeptide (GIP), dipeptidyl peptidase 4 (DPP-4) soluble form, and IR indexes by homeostatic model assessment (HOMA2) were assessed. A multivariable analysis adjusted for IR-related factors was performed. Additionally, ten patients and ten control subjects underwent a 566-kcal meal test so that we could further study the postprandial differences of these molecules between patients and control subjects.

Results

Insulin, C-peptide, and HOMA2-IR indexes were higher in patients than in control subjects. This was also the case for GLP-1 (0.49 ± 1.28 vs. 0.71 ± 0.22 ng/ml, p = 0.000) and GIP (0.37 ± 0.40 vs. 1.78 ± 0.51 ng/ml, p = 0.000). These differences remained significant after multivariable adjustment including glucocorticoid intake. Disease Activity Score in 28 joints with erythrocyte sedimentation rate (β coefficient 46, 95% CI 6–87, p = 0.026) and Clinical Disease Activity Index (β coefficient 7.74, 95% CI 1.29–14.20, p = 0.019) were associated with DPP-4 serum levels. GLP-1 positively correlated with β-cell function (HOMA2 of β-cell production calculated with C-peptide) in patients but not in control subjects (interaction p = 0.003). The meal test in patients with RA revealed a higher total and late response AUC for glucose response, a later maximal response of C-peptide, and a flatter curve in GIP response.

Conclusions

The incretin-insulin axis, both during fasting and postprandial, is impaired in patients with RA.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1431-9) contains supplementary material, which is available to authorized users.

Angiopoietin-like 4: A molecular link between insulin resistance and rheumatoid arthritis

Recent evidence suggests that common factor(s) or molecule(s) might regulate lipid and glucose metabolism, inflammation, and bone and cartilage degeneration. These findings may be particularly relevant for cases of rheumatoid arthritis, in which chronic inflammation occurs in an autoimmune context and causes the degradation of articular joints as well as insulin resistance and cardiovascular complications. Candidates for this common regulatory system include signals mediated by peroxisome proliferator-activated regulator and its response factor, angiopoietin-like 4. The expression and bioactivity of angiopoietin-like 4, an adipocytokine that was originally reported to have an angiogenic function, have been detected not only in the vascular system and adipose tissue but also in rheumatoid joints. An essential role for angiopoietin-like 4 has been established in dyslipidemia, and recent reports indicate that it may modulate bone and cartilage catabolism in rheumatoid arthritis. The enhanced expression of angiopoietin-like 4 in rheumatoid arthritis may explain the occurrence of insulin resistance, cardiovascular risk, and joint destruction, thereby suggesting that this molecule could be a potential target for anti-rheumatoid arthritis strategies. This review describes recent research on the role of angiopoietin-like 4 in chronic inflammatory conditions and rheumatoid arthritis, as well as potential therapeutic candidates. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:939-943, 2017.

Metabolic syndrome and its components among rheumatoid arthritis patients: A comprehensive updated systematic review and meta-analysis

BACKGROUND

Estimating the current global prevalence of metabolic syndrome (MetS), and its components, among rheumatoid arthritis (RA) patients is necessary in order to formulate preventative strategies and to ensure there are adequate community resources available for these patients. Furthermore, the association between RA and MetS is controversial and has not previously been comprehensively assessed. Therefore, the present study aimed to: 1) determine the prevalence of MetS, and its components, among RA patients across the world 2) update the odds ratio of MetS in RA patients, compared to healthy controls, using a comprehensive systematic review and meta-analysis.

METHODS

International databases, including: the Web of Science, PubMed, Scopus, Embase, CINAHL and other relevant databases were searched to identify English language articles which reported the prevalence and risk of MetS in RA patients between January 2000 and August 2016. The meta-analysis only included studies which clearly described the time and location of the study, utilised adequate sampling strategies, and appropriate statistical analyses.

RESULTS

The meta-analyses of prevalence (70 studies [n = 12612]) and risk (43 studies [n = 35220]) of MetS in RA patients were undertaken separately. The overall pooled prevalence of MetS was 30.65% (95% CI: 27.87-33.43), but this varied from 14.32% (95% CI: 10.59-18.05) to 37.83% (95% CI: 31.05-44.61), based upon the diagnostic criteria used. The prevalence of MetS also varied slightly between males (31.94%, 95% CI: 24.37-39.51) and females (33.03%, 95% CI: 28.09-37.97), but this was not statistically significant. The overall pooled odds ratio (OR) of MetS in RA patients, compared to healthy controls, was 1.44 (95% CI: 1.20-1.74), but this ranged from 0.70 (95% CI: 0.27-1.76) to 4.09 (95% CI: 2.03-8.25), depending on the criteria used. The mean age and diagnostic criteria of MetS were identified as sources of heterogeneity in the estimated odds ratios between studies (P<0.05).

CONCLUSIONS

According to the high prevalence of MetS in RA patients, and high risk of MetS, measuring metabolic syndrome in RA patients is strongly recommended. Furthermore, as high waist circumference (WC) is the most common metabolic syndrome component, more attention must be paid to nutrition and weight loss among those with RA.

Th17 and IL-17 Cause Acceleration of Inflammation and Fat Loss by Inducing α2-Glycoprotein 1 (AZGP1) in Rheumatoid Arthritis with High-Fat Diet

Rheumatoid arthritis (RA) is a chronic autoimmune disorder that affects the joints. High-fat diet (HFD) is a risk factor for RA and is related to inflammation but responds minimally to medication. Given the association between HFD and inflammation, it is important to understand the function of inflammation-related T cells in RA with HFD. Collagen-induced arthritis (CIA), a model of RA, was induced in HFD mice by injection of collagen II, and metabolic markers and T cells were analyzed. The metabolic index and IgG assay results were higher in HFD-CIA mice than in nonfat diet-CIA mice. Numbers of inflammation-related T cells and macrophages, such as Th1 and Th17 cells and M1 macrophages, were higher in spleens of HFD-CIA mice. HFD-CIA mice had a high level of α₂-glycoprotein 1 (Azgp1), a soluble protein that stimulates lipolysis. To examine the association between Azgp1 and Th17 cells, the reciprocal effects of Azgp1 and IL-17 on Th17 differentiation and lipid metabolism were measured. Interestingly, Azgp1 increased the Th17 population of splenocytes. Taken together, our data suggest that the acceleration of fat loss caused by Azgp1 in RA with metabolic syndrome is related to the increase of IL-17. Mice injected with the Azgp1-overexpression vector exhibited more severe CIA compared with the mock vector-injected mice.

Prevalence of Metabolic Syndrome in Treatment Naïve Rheumatoid Arthritis and Correlation With Disease Parameters

Objectives

This study aims to assess the prevalence of metabolic syndrome (MetS) in treatment naïve rheumatoid arthritis (RA) in an Indian population and correlate RA disease characteristics with presence of MetS.

Patients and methods

The study included 84 RA patients (18 males, 66 females; mean age 44.8±12.5 years; range 18 to 72 years) diagnosed according to 2010 American College of Rheumatology-European League Against Rheumatism classification criteria who were treatment naïve or did not receive disease modifying antirheumatic drugs for more than six weeks and 120 age and sex-matched apparently healthy controls (35 males, 85 females; mean age 44.1±12.7 years; range 18 to 75 years). The frequency of MetS was assessed using National Cholesterol Education Program- Adult Treatment Panel III 2004 revised criteria. Patients were also assessed in terms of disease activity, using disease activity score 28 erythrocyte sedimentation rate. Logistic regression was used to identify predictors of MetS in RA.

Results

Metabolic syndrome was found in 39.28% of RA group and 20% of control group according to National Cholesterol Education Program- Adult Treatment Panel III 2004 (p<0.005). MetS was most commonly detected in the 51 to 60 age group (65%). RA group was significantly more likely to have low high-density lipoprotein (63.09%), high triglyceride (53.57%), elevated blood pressure (41.66%) levels, and elevated waist circumference (38.09%). In RA group, disease activity score 28 (odds ratio: 6.51, confidence interval: 1.19-35.46 p=0.03), C-reactive protein (odds ratio: 1.13, confidence interval: 1.05-1.21 p<0.001), and duration of disease (odds ratio: 1.82, confidence interval: 1.04-3.18 p=0.03) remained independent predictors for presence of MetS in RA.

Conclusion

The frequency of MetS was higher in RA group compared to control group. Higher systemic inflammatory marker, disease duration, and disease activity score 28 remained independent predictors associated with presence of MetS. These findings suggest that RA patients should be screened early for presence of MetS to check for and reduce risk of atherosclerotic vascular diseases.

Recent advances in the understanding of molecular mechanisms of cartilage degeneration, synovitis and subchondral bone changes in osteoarthritis

Osteoarthritis (OA), the most common form of degenerative joint disease, is linked to high morbidity. It is predicted to be the single greatest cause of disability in the general population by 2030. The development of disease-modifying therapy for OA currently face great obstacle mainly because the onset and development of the disease involve complex molecular mechanisms. In this review, we will comprehensively summarize biological and pathological mechanisms of three key aspects: degeneration of articular cartilage, synovial immunopathogenesis, and changes in subchondral bone. For each tissue, we will focus on the molecular receptors, cytokines, peptidases, related cell, and signal pathways. Agents that specifically block mechanisms involved in synovial inflammation, degeneration of articular cartilage, and subchondral bone remodeling can potentially be exploited to produce targeted therapy for OA. Such new comprehensive agents will benefit affected patients and bring exciting new hope for the treatment of OA.

Management of Hidradenitis Suppurativa in Patients with Metabolic Comorbidities

Hidradenitis suppurativa is a chronic inflammatory skin condition associated with an increased prevalence of individual metabolic conditions such as insulin resistance, obesity, hyperlipidemia, hypertension, and with the metabolic syndrome, as a constellation of these risk factors. This places affected patients at an increased risk of early cardiovascular morbidity and mortality. Moreover, many of the therapeutic options, including the newer biologics, used in the treatment of hidradenitis suppurativa have both beneficial and adverse metabolic effects. Therefore, it is critical for physicians to consider the complex interactions between the disease process and the treatment options in the holistic management of these patients with an intrinsically higher risk of metabolic consequences. Other chronic systemic inflammatory diseases such as psoriasis and rheumatoid arthritis have been studied more extensively with regard to their associations and share an underlying link with the metabolic syndrome; we can draw upon the existing knowledge in our understanding and management of hidradenitis suppurativa.

Energy expenditure and nutritional complications of metabolic syndrome and rheumatoid cachexia in rheumatoid arthritis: an observational study using calorimetry and actimetry

OBJECTIVE

Altered energy expenditure may contribute to the nutritional complications of RA, metabolic syndrome (MS) and rheumatoid cachexia (RC). The main aim of this study was to evaluate whether the altered resting energy expenditure (REE) and physical activity (PA)-related energy expenditure (EE) are related to the duration of RA and inflammatory activity and nutritional complications in RA.

METHODS

Among patients with well-characterized RA (duration, activity: DAS28 ESR), we measured REE by indirect calorimetry, and PA-EE by actimetry (SenseWear Armband). MS was defined according to the International Diabetes Federation criteria and RC from DXA body composition analysis. The relations between the characteristics and nutritional complications, and EE were analysed by linear regression.

RESULTS

Fifty-seven patients were included [73% women, age 57 (10) years] with a wide range of disease duration: 3.8 (3.0) years, and DAS28 ESR: 3.9 (1.4). The mean REE was 1486 (256) kcal/day, associated with the DAS28 ESR (β = +0.21, P = 0.02 after adjusting for gender and fat free mass). The prevalence of MS and RC was, respectively, 24 and 18%, and they were unrelated to each other. The patients with MS and/or RC had double the longstanding RA score (P < 0.05), twice the homeostasis model assessment of insulin resistance values (P = 0.052) and halved levels of PA (P < 0.05 for metabolic equivalent tasks (METs) and number of steps/day). Two modifiable factors were associated with the presence of MS and/or RC: a low level of PA as METs [exp(B) = 0.03, P = 0.009] and the use of glucocorticoids [exp(B) = 4.08, P = 0.046].

CONCLUSION

Low levels of PA and treatment by glucocorticoids are associated with the nutritional complications of RA, suggesting the potential for therapeutic interventions.