Nutritional status in relation to adipokines and oxidative stress is associated with disease activity in patients with rheumatoid arthritis

Association of Mediterranean diet pattern with disease activity in the patients with rheumatoid arthritis: A cross-sectional study on Iranian patients

BACKGROUND & AIMS

Rheumatoid arthritis is a systemic autoimmune disease that causes joint erosion, as well as damage to extra-articular organs. The aim of this study was the investigation of the association between the Mediterranean diet quality index with disease activity in patients with rheumatoid arthritis.

METHODS

In this cross-sectional study 184 females with rheumatoid arthritis were studied in Kermanshah, Iran. The American College of Rheumatology's 2010 criteria were used to diagnose RA. The biochemical tests including erythrocyte sedimentation rate, C-reactive protein, rheumatoid facto, anti-nuclear antibody titration, antibodies against cyclic citrulline peptide, disease activity score 28 and the food frequency questionnaire was used to assess rheumatoid arthritis activity and the Mediterranean diet quality index, respectively. To compare the dietary intakes of participants across tertiles of Mediterranean diet score, we used Analysis of Variance. Multinomial logistic regression with three adjusted models was used to investigate the association between Mediterranean diet score with disease activity.

RESULTS

184 eligible patients with rheumatoid arthritis participated in this study. The mean age and duration of disease, body mass index, waist circumference and percent body fat did not differ significantly among the tertiles of the Mediterranean diet score (P-value>0.05). Participants in the highest tertile of Mediterranean diet score had significantly greater intakes of fruits, vegetables, fish, legume, nuts and had lowest intake of grains (refrain grain) and red and process meats to white meat ratio (P-value<0.05). There was no significant difference in terms of variables related to disease activity among the tertiles of the Mediterranean score (P-value>0.05). In multi-adjusted models, the odds ratio of Mediterranean diet scores no significant different in the third as compared to the first tertile of Mediterranean diet score (P-value>0.05).

CONCLUSION

Based on our findings there is no association between the Mediterranean diet score and disease activity of people with rheumatoid arthritis.

Nutrition Patterns and Their Gender Differences among Rheumatoid Arthritis Patients: A Descriptive Study

Dietary factors probably play a role in the pathogenesis and clinical course of rheumatoid arthritis (RA). There is a paucity of specific dietary guidelines for RA patients and little information on their implementation in daily life. Therefore, this study aimed to determine the nutritional status and provision of nutritional education among outpatients with RA. Here, 61 patients were included with a sex ratio of 2.03 (f/m). Based on BMI, 22% of women were overweight and 32% obese, whereas 50% of men were overweight and 30% obese. Fasting blood and a 3-day estimated dietary record were collected. Additionally, patients were asked whether they had already received information about a specific diet as part of their disease treatment plan. Elevated total cholesterol levels were found in 76% of women and in 60% of men caused by increased non-HDL-C levels. The dietary intake assessment showed a lower self-reported intake of energy, polyunsaturated fat, carbohydrates, fiber, and several micronutrients than recommended. Regarding healthy eating, all patients reported familiarity with dietary recommendations, but found it difficult to implement the recommendations into their diets. These findings suggested that RA patients need more specific recommendations and education in clinical practice to improve the quality of their diet.

Inadequate Dietary Nutrient Intake in Patients With Rheumatoid Arthritis in Southwestern Sweden: A Cross-Sectional Study

Background

Patients with rheumatoid arthritis (RA), who suffer from impaired physical function and fatigue, may have difficulties with grocery shopping and preparing meals. Also, to improve symptoms, patients often experiment with diets but seldom consult a dietitian. Although this could lead to a nutritiously deprived diet, an up-to-date, thorough description of the nutrient intake in Swedish patients with RA is absent. Here, we investigated the habitual dietary energy and nutrient intake in patients with RA living in southwestern Sweden.

Materials and Methods

Three-day food records performed at two time points during the ADIRA (Anti-inflammatory Diet In Rheumatoid Arthritis) trial, were used. The intake of energy and nutrients was analyzed using The Swedish Food Composition Database.

Results

A total of 62 participants (50 females, 12 males) were included in the study, where 18 participants completed one 3-day food record and 44 participants completed two 3-day food records. Median (IQR) intake of total fat was above or in the upper range of recommendations (females: 37.1 [32.5, 41.7] energy percent (E%), and males: 40.3 [37.5, 42.9] E%). Median (IQR) intake of saturated fatty acids exceeded recommendations (females: 14.9 [12.5, 17.0] E% and males: 15.4 [12.2, 17.0] E%), while median (IQR) carbohydrate and fiber intakes were below recommendations (females: 41.7 [36.3, 45.4] E% and 17.2 [12.8, 20.9] g, respectively, and males: 38.8 [35.2, 40,3] E% and 18.5 [15.7, 21.0] g, respectively). The reported intake of other macronutrients was in line with recommendations. For several micronutrients, e.g., vitamin A and D, folate, and calcium, median intake was below recommended intake. Vitamin A intake was especially low and did not reach lower intake level (LI) for 14 and 17% of females and males, respectively. For females, about 10% did not reach LI for vitamin D, calcium, and riboflavin.

Conclusion

We found that patients with RA residing in southwestern Sweden reported a high intake of saturated fatty acids and low intake of fiber and several micronutrients.

Clinical Trial Registration

[https://clinicaltrials.gov/ct2/show/NCT02941055?term=NCT02941055&amp;draw=2&amp;rank=1], identifier [NCT02941055].

The Relationship between Fatty Acids and the Development, Course and Treatment of Rheumatoid Arthritis

For this systematic review, a search of the relevant literature was conducted in the EMBASE and PubMed databases. We used the following terms: ‘rheumatoid arthritis’ in conjunction with ‘fatty acid’. The following inclusion criteria had to be satisfied for the studies to be included in the analysis: an RCT/observational/cohort study published in English. A total of seventy-one studies were analysed. The presented systematic review of the available data indicates that increased consumption of omega-3 fatty acids (FAs) may have a beneficial effect on human health by decreasing pain and disease activity in patients with RA. The beneficial effect of unsaturated FA on the clinical parameters of RA was demonstrated in all 71 studies analysed. The content of omega-3 FAs in the diet and the consumption of fish, which are their main source, may contribute to a reduced incidence of RA. FAs are an essential component in the synthesis of eicosanoids that exhibit anti-inflammatory properties. Due to the documented positive influence of unsaturated FAs on treatment outcomes, the use of a diet rich in long-chain unsaturated FAs should be the standard of care, along with pharmacotherapy, in the treatment of RA patients. An important element in the control of the treatment process should be the routine assessment of the quality of life of RA patients.

C-Reactive Protein-to-Albumin Ratio: A Novel Inflammatory Marker and Disease Activity Sign in Early Rheumatoid Arthritis

Objective A novel inflammation-based score, C-reactive protein (CRP)-to-albumin ratio (CAR), has been shown to have an association with the inflammatory status in several diseases. We aimed to analyse the association between CAR and disease activity in patients with early rheumatoid arthritis (RA) and to determine the cut-off value of CAR in early and established RA.

Methods A total of 177 patients with RA and 111 age and gender-matched healthy controls were included in this study. Cases with a disease duration of less than 1 year were classified as early RA. Serum albumin, CRP, erythrocyte sedimentation rate (ESR), Disease Activity Score-28 (DAS-28-ESR), Clinical Disease Activity Index (CDAI) and Health Assessment Questionnaire (HAQ) scores were recorded.

Results CAR was 2.44 (0.21–30.83) in the RA group and 0.45 (0.21–10.47) in the control group (p<0.001). Eighty-seven (49.15%) of the RA cases were classified as early RA. The analyses indicated that the ESR, CRP and CAR values were higher in patients with early RA than in those with established RA and controls. CAR was correlated with albumin, CRP, ESH, DAS-28 and HAQ scores in both early RA and established RA groups. The receiver operating characteristic curves revealed a CAR cut-off value of 2.67 (80% sensitivity and 85% specificity) and 1.63 (77% sensitivity and 72% specificity) for the prediction of early and established RA, respectively.

Conclusion CAR, a formulated ratio, has been described as a predictor for disease activity in patients with early RA as well as in those with established RA. However, CAR has higher sensitivity and specificity for early RA than for established RA.

Association of Dietary Inflammatory Index (DII) with disease activity and inflammatory cytokines in the patients with rheumatoid arthritis

OBJECTIVES

This study aimed, at first, to assess Dietary Inflammatory Index (DII) in participants with rheumatoid arthritis (RA) and compare them with healthy controls. Then, to evaluate the association of DII with the risk of RA occurrence, the severity of disease, and systemic inflammation.

METHODS

This case-control study enrolled 100 newly diagnosed cases with RA and 100 age and sex-matched healthy controls. DII was computed based on the individuals' FFQ-derived dietary data. Serum levels of inflammatory markers, including the high sensitivity C-reactive protein (hs-CRP) and Tumour Necrosis Factor-alpha (TNF-α), were measured using the ELISA method; and the severity of the disease was assessed based on the disease activity score 28 (DAS-28).

RESULTS

The mean DII score was higher in the RA patients as compared with that in the controls (0.66 ± 0.23 vs. -0.58 ± 0.19, P = .002). Patients with the highest DII had significantly higher serum inflammatory (hs-CRP and TNF) and clinical markers (DAS-28 score and the number of tender joints). A significant univariate relationship between DII score and risk of RA incident [6.48 (95% CI: 1.79 to 23.44)] disappeared in multivariate analysis. For each 1-unit increase in DII, the DAS-28 score was raised by 1.11 times (P = .001).

CONCLUSION

An inflammatory diet may act as a potential risk factor contributing to the development of RA and its severity. Therefore, dietary modification with the goal of reducing the DII score could be a beneficial strategy to improve the clinical outcomes in such patients.

Causal association of monounsaturated fatty acids with rheumatoid arthritis but not osteoarthritis: A two-sample Mendelian randomization study

OBJECTIVES

Previous studies have indicated that dietary monounsaturated fatty acids (MUFAs) are associated with decreased risk of osteoarthritis (OA) and rheumatoid arthritis (RA). However, the causality of the observed associations is largely undetermined. We sought to ascertain the potential causal roles of two of the most common MUFAs, oleic acid and palmitoleic acid, in RA and OA risk using a two-sample Mendelian randomization approach.

METHODS

For the outcomes, we used summary-level data for RA (14 361 people with RA and 43 923 controls) and OA (10 083 people with OA and 40 425 controls) from two genome-wide association studies in European ancestry. For the exposures, five single-nucleotide polymorphisms associated with palmitoleic acid and one associated with oleic acid with genome-wide significance (P < 5 × 10^-8) were selected as instrumental variables. The causal effects were estimated using the inverse-variance weighted method with several sensitivity analyses.

RESULTS

For genetically predicted levels, an increase of one SD in palmitoleic acid (odds ratio, 0.24; 95% confidence interval, 0.10-0.59; P = 0.002) and oleic acid (odds ratio, 0.78; 95% confidence interval, 0.67-0.90; P < 0.001) was significantly associated with lower risk of RA. However, genetic predisposition to either of the two individual MUFAs was not associated with OA risk. Sensitivity analyses yielded similar results.

CONCLUSIONS

Our Mendelian randomization analyses suggest a causal relationship between higher genetically predicted MUFA levels and lower risks of RA. However, the causality between MUFAs and OA cannot be inferred from this study. Further research is required to unravel the role of MUFA supplementation in arthritis prevention.

Association of Leptin Gene Polymorphisms with Rheumatoid Arthritis in a Chinese Population

Background

Recently, increasing studies have revealed that leptin is involved in the development of rheumatoid arthritis (RA). This study is aimed at exploring the association of leptin gene single nucleotide polymorphisms (SNPs) with susceptibility to RA in a Chinese population.

Methods

We recruited 600 RA patients and 600 healthy controls from a Chinese population and analyzed their three leptin SNPs (rs10244329, rs2071045, and rs2167270) using the improved Multiplex Ligase Detection Reaction (iMLDR) assays. The associations of these SNPs with clinical manifestations of RA were also analyzed. Enzyme-linked immunosorbent assay (ELISA) was performed for plasma leptin determination.

Results

No significant difference in either allele or genotype frequencies of these three SNPs between RA patients and healthy controls was observed (all P > 0.05). Association between the genotype effects of dominant, recessive models was also not found (all P > 0.05). No significant difference in plasma leptin levels was detected between RA patients and controls (P > 0.05).

Conclusion

Leptin gene (rs10244329, rs2071045, and rs2167270) polymorphisms are not associated with RA genetic susceptibility and its clinical features in the Chinese population.

A Cohort Study of Liver Involvement in Patients With Adult-Onset Still's Disease: Prevalence, Characteristics and Impact on Prognosis

Objective: Adult-onset Still's disease (AOSD) is a systemic disorder commonly accompanied by liver involvement. This study aims to illustrate the detailed information of liver abnormalities in patients with AOSD and evaluate the impact on the prognosis.

Methods: A total number of 128 hospitalized patients, who met the Yamaguchi criteria of AOSD in the Department of Rheumatology and Immunology, Ruijin Hospital from July 2016 to August 2019 were consecutively enrolled and followed up. The demographic characteristics, clinical features, laboratory tests, treatments and prognosis were recorded. Correlations of liver function tests (LFTs) with disease activity and laboratory parameters were analyzed by the Spearman test. Risk factors of the refractory AOSD were evaluated by multivariate logistic regression analysis.

Results: Liver involvement was presented in 104 (81.3%) patients with AOSD. We observed that 34 (32.7%) patients were with mild elevation, 32 (30.8%) patients were with moderate elevation, and 38 (36.5%) patients were with severe elevation. The majority of elevated ALT, AST and ALP decreased to normal within the range of 2 months, except for GGT. Furthermore, the LFTs were found significantly correlated with disease activity. Besides, we found patients with higher levels of LFTs tended to require more intensive treatments and suffered from poorer prognosis. Multivariate logistic regression analysis showed ALP ≥ 141 IU/L and GGT ≥ 132 IU/L are independent risk factors of refractory AOSD.

Conclusion: Liver involvement is common in patients with AOSD, the levels of LFTs are associated with disease activity and related to the treatment strategies and prognosis.

Changes to Body Composition in Women With Long-Standing Established Rheumatoid Arthritis: Differences by Level of Disease Activity

INTRODUCTION

Few studies on rheumatoid arthritis have investigated disease activity and body composition by dual-energy X-ray absorptiometry including evaluation of visceral adipose tissue. Thus, we sought to verify the association between body composition by dual-energy X-ray absorptiometry, including visceral adipose tissue, and inflammatory activity in long-standing established rheumatoid arthritis.

METHODS

Seventy-eight postmenopausal women with rheumatoid arthritis (American College of Rheumatology 2010) were studied. Disease activity was assessed by composite indexes (DAS28, CDAI, SDAI) and C-reactive protein. Potential association between body composition and disease activity was analysed by Pearson correlation and Tukey´s test (p < 0.05).

RESULTS

There was significant negative correlation between C-reactive protein and appendicular lean mass index (r = -0.234, p = 0.039). After adjusting for confounding variables, women with C-reactive protein >10 mg/L had a lower appendicular lean mass index than those with C-reactive protein 5-10 mg/L and <5 mg/L (6.3 ± 0.8 kg/m² vs 7.2 ± 1.2 kg/m² vs 6.8 ± 1.0 kg/m², respectively; p = 0.013). Women with moderate inflammation (C-reactive protein 5-10 mg/L) had more fat than those with C-reactive protein >10 mg/L and C-reactive protein <5 mg/L (12.4 ± 3.5 kg/m² vs 9.9 ± 3.6 kg/m² vs 10.5 ± 2.8 kg/m², respectively; p = 0.040), as well as more visceral adipose tissue than women with higher and lower C-reactive protein (812.5 ± 266.4 cm³ vs 604.3 ± 236.3cm³ vs 658.9 ± 255.6 cm³; p = 0.009).

CONCLUSIONS

High inflammatory activity that persists after a long disease duration was associated with both lower muscle and fat mass (including visceral adipose tissue), which is suggestive of more exuberant rheumatoid cachexia. Conversely, moderate activity was associated with greater visceral adipose tissue, which is associated with increased cardiovascular risk. These results point to the existence of different body composition profiles according to inflammatory status and the importance of individualized approaches to muscle mass and adiposity according to disease activity level in long-standing rheumatoid arthritis.

Intake frequency of vegetables or seafoods negatively correlates with disease activity of rheumatoid arthritis

Objective

To clarify the relationship between dietary habit and disease activity of rheumatoid arthritis (RA).

Methods

This study enrolled RA patients who met the ACR/EULAR 2010 classification criteria from Kyoto University Rheumatoid Arthritis Management Alliance (KURAMA) cohort in 2015. 22-item food frequency questionnaire (FFQ) was taken for the measurement of dietary habit in a single-institution cohort of RA (Kyoto University Rheumatoid Arthritis Management Alliance: KURAMA) in 2015. The disease activities of RA using the Disease Activity Score calculated based on the erythrocyte sedimentation rate (DAS28-ESR), Simplified Disease Activity Index (SDAI), Health Assessment Questionnaire (HAQ), and serum matrix metalloproteinase-3 (MMP-3) level, the use of disease-modifying anti-rheumatic drugs (DMARDs), disease duration, rheumatoid factor, anti-cyclic citrullinated antibody, and body mass index were also examined. All of them were combined and statistically analyzed.

Results

441 RA patients (81% women; mean age 65 years; mean disease duration 15 years) were enrolled from the KURAMA cohort. Average Disease Activity Score-28 using the erythrocyte sedimentation rate (DAS28-ESR) was 2.7. Univariate analysis showed that intake frequency of vegetables had a statistically significant negative correlation with disease activity markers, such as DAS28-ESR (ρ = −0.11, p<0.01), Simplified Disease Activity Index (SDAI) (ρ = −0.16, p<0.001), matrix metalloproteinase-3 (MMP-3) (ρ = −0.21, p<0.0001), and Health Assessment Questionnaire (HAQ) (ρ = −0.13, p<0.01). Factor analysis with varimax rotation was done to simplify the relevance of disease activity to various food items. 22 foods were categorized into five dietary patterns: “seafoods”, “vegetables/fruits”, “meats/fried foods”, “snacks”, and “processed foods”. The multivariate analysis adjusted for clinically significant confounders showed that “seafoods” had statistically significant negative correlations with DAS28-ESR (β = −0.15, p<0.01), SDAI (β = −0.18, p<0.001), MMP-3 (β = −0.15, p<0.01), and HAQ (β = −0.24, p<0.0001). “Vegetables/fruits” had statistically significant negative correlations with SDAI (β = −0.11 p<0.05), MMP-3 (β = −0.12, p<0.01), and HAQ (β = −0.11, p<0.05)

Conclusions

These results suggest that high intake frequency of vegetables/fruits and/or seafoods might correlate with low disease activity.

Incidence and effect of insulin resistance on progression of atherosclerosis in rheumatoid arthritis patients of long disease duration

Background

The continued atherosclerotic risk in rheumatoid arthritis (RA) has been inadequately explained by conventional factors. Chronic inflammation and endothelial activation seems responsible for developing insulin resistance (IR). The study was aimed to assess the role of inflammation and endothelial activation causing IR in long term RA patients leading to increased atherosclerotic risk.

Methods

Fifty (25 long-duration and 25 short-duration) RA patients and twenty-three healthy controls were recruited excluding potential confounding co-morbidities. Fasting insulin, proinflammatory cytokines, endothelial stress markers and adipokines were quantified by ELISA. Homeostasis Model Assessment (HOMA)-IR calculated using glucose and insulin values. Atherosclerotic indices were measured using ultrasound.

Results

Lipid profile was comparable among groups. Mean carotid intima media thickness (cIMT) was significantly higher in both RA groups (p = 0.0062) compared to controls. HOMA-IR was significantly higher in long-duration RA (p = 0.005); it showed significant associations with DAS 28 (p = 0.01) and hsCRP (p = 0.03) in this subset. Mean cIMT for short-duration RA (p = 0.02) and long-duration RA (p = 0.0006) respectively was also significantly associated with HOMA-IR. Pro-inflammatory markers like TNF-α, resistin and leptin were highest in long-duration RA, higher in short-duration RA when compared to control group respectively. HOMA-IR was significantly dependent on TNF-α (p = 0.008), resistin (p = 0.031), leptin (p = 0.0054). Mean cIMT showed association with all parameters mainly with TNF-α (p = 0.001), iNOS (p = 0.001), resistin (p = 0.008) and leptin (p = 0.04).

Conclusions

Persistent inflammation leads to altered adipokine secretion promoting IR in RA patients with long disease duration. Treatment with conventional disease modifying anti-rheumatic drugs (DMARDs) is incomplete to control chronic inflammation and limit progression of atherosclerosis.

Poor Dietary Quality Is Associated with Increased Inflammation in Swedish Patients with Rheumatoid Arthritis

The aim was to study whether dietary quality was associated with disease activity and inflammation among patients with rheumatoid arthritis (RA). This cross-sectional analysis included 66 Swedish participants, who each completed a food frequency questionnaire (FFQ) at screening. Food intake was scored by a dietary quality index created by the Swedish National Food Agency. Disease activity was measured as Disease Activity Score 28 (DAS28), based on erythrocyte sedimentation rate (ESR), a patient administered visual analogue scale of perceived global health and the number of tender and swollen joints out of 28 examined. Inflammation was measured as ESR and C-reactive protein (hs-CRP). Associations between dietary quality, disease activity and inflammation were evaluated using multivariable linear regression analysis. High dietary quality (high intake of fish, shellfish, whole grain, fruit and vegetables and low intake of sausages and sweets) was not related to DAS28 (B = −0.02, p = 0.787). However, dietary quality was significantly negatively associated with hs-CRP (B = −0.6, p = 0.044) and ESR (B = −2.4, p = 0.002) after adjusting for body mass index, age, education, smoking and gender. Both hs-CRP and ESR decreased with increasing dietary quality. In conclusion, among patients with RA, high dietary quality was associated with reduced inflammation but not with disease activity.

The association between albumin-dNLR score and disease activity in patients with rheumatoid arthritis

BACKGROUND

Recently, clinical studies have described an association between albumin and the derived neutrophil to lymphocyte ratio (dNLR) with several diseases. This study was aimed to investigate the albumin-dNLR (ALB-dNLR) score in rheumatoid arthritis (RA) patients and assess its relationship with clinical and laboratory parameters of RA.

METHODS

We retrospectively enrolled 127 RA patients, 155 osteoarthritis (OA) patients, and 155 healthy controls. The ALB-dNLR score was based on serum albumin level, neutrophil count, and white cell count. The Spearman's rank test was used to measure the correlations between ALB-dNLR score and disease activity as well as laboratory indexes.

RESULTS

The ALB-dNLR score was significantly higher in RA patients than in OA patients (P < 0.001) and in healthy controls (P < 0.001). The proportion of higher ALB-dNLR score has been raised along with increased disease activity (P < 0.001). The Spearman's rank test showed that ALB-dNLR score was positively associated with DAS28 score, CRP, ESR, IgA, and platelet count. Moreover, the receiver operating characteristic (ROC) curve showed that the area under the curve (AUC) of ALB-dNLR was 0.693 (95% CI: 0.631-0.755), which was higher than that of albumin (AUC: 0.625, 95% CI: 0.559-0.692) and dNLR (AUC: 0.680, 95% CI: 0.617-0.743) alone.

CONCLUSIONS

The results demonstrate that the ALB-dNLR score increased in RA patients. The ALB-dNLR score may be a useful marker to estimate the disease activity of RA patients.

The Influence of LPS-Induced Maternal Inflammation on Postnatal Collagen-Induced Arthritis

Maternal health and nutritional status influence offspring health and the diseases that may develop in them. The effects of maternal inflammation on offspring from the perspective of the inflammatory response and immune changes are not fully understood. We hypothesized that maternal inflammation modulates immune and metabolic functions, affecting the pathophysiology of inflammatory diseases in offspring. This study investigated whether maternal inflammation affects the onset of collagen-induced arthritis (CIA), a murine model of human rheumatoid arthritis. Female DBA/1J mice received a single intraperitoneal injection of lipopolysaccharide (LPS) 5 days before conception. Male offspring of LPS-treated dams were placed in the maternal LPS group (MLG). To induce CIA, type II collagen (CII) was emulsified with Freund's complete adjuvant and injected twice into each mouse, at 13 and 16 weeks. The offspring were sacrificed at 26 weeks to analyze immunological and metabolic parameters. The degree of joint swelling at an early stage of CIA was lower in the MLG than in the control group. From histological analysis, the severity of joint destruction (severity of arthritis score) and CII-specific IgG titer were significantly lower in the MLG. However, at 26 weeks, serum interleukin (IL)-6 levels, an index of CIA disease activity, were significantly higher in the MLG. Moreover, serum leptin levels were lower in the MLG, and a negative correlation between leptin and serum IL-6 was observed. In conclusion, maternal inflammation does not merely suppress inflammation; it may delay CIA in offspring. The analysis of inflammatory cytokines and leptin concentrations at 26 weeks suggests that the pathophysiology of arthritis was worsening. This study also suggests that maternal inflammation modulates postnatal inflammatory response patterns in offspring.

Leptin as an obesity marker in rheumatoid arthritis

The determination of excess of body fat mass provides a more suitable determinant of obesity in rheumatoid arthritis patients; however, body mass index (BMI) may not be accurate for the quantification of adiposity. To identify a marker of excess adiposity in women with rheumatoid arthritis (RA) using different methods for fat mass evaluation. A cross-sectional study was conducted in adult female patients with RA. Disease activity was assessed by DAS28-ESR, and obesity was determined by waist circumference (WC), BMI and dual-energy X-ray absorptiometry (DXA). The Human Bone Metabolism kit (Merck Millipore, Darmstadt, Alemanha) was used to determine the plasma levels of leptin, TNF-α, IL-6, and IL-1β by quantification of serum proteins by technical microspheres (LUMINEX, TX, USA). Adiponectin was measured by enzyme-linked immunosorbent assay sandwich kit (R&D Systems, Minneapolis, MN, USA). Eighty-nine female patients, median age of 55.4 (± 11.6) years, and median disease duration of 16.4 (± 14.9) years were included. The frequency of obesity was 33.7% according to BMI, 89.9% with WC, and 56.1% with DXA. The median serum leptin concentration was the only marker that correlated with body fat percentage according to the three methods. This correlation was positive and not influenced by DAS28, C-reactive protein, erythrocyte sedimentation rate, or inflammatory cytokines levels (IL-6, TNF-α, IL-1β). Analysis of ROC curves determined the cut-off point of 10.3 ng/mL of leptin as an obesity marker, with a sensitivity of 96.43% and a specificity of 23.81%. Serum leptin correlates positively with fat mass and is potentially useful in excess fat mass determination in clinical practice.

A randomized controlled cross-over trial investigating the effect of anti-inflammatory diet on disease activity and quality of life in rheumatoid arthritis: the Anti-inflammatory Diet In Rheumatoid Arthritis (ADIRA) study protocol

Background

Rheumatoid arthritis (RA) is a chronic inflammatory disease that affects 0.5–1.0% of the population, and where many patients in spite of modern pharmacological treatment fail to reach remission. This affects physical as well as mental wellbeing and leads to severely reduced quality of life and reduced work capacity, thus yielding high individual as well as societal costs. As a complement to modern pharmacological treatment, lifestyle intervention should be evaluated as a treatment option. Scientific evidence exists for anti-inflammatory effects by single foods on RA, but no study exists where these foods have been combined to obtain maximum effect and thus offer a substantial improvement in patient life quality. The main goal of the randomized cross-over trial ADIRA (Anti-inflammatory Diet In Rheumatoid Arthritis) is to test the hypothesis that an anti-inflammatory diet intervention, compared to a regular diet, will decrease disease activity and improve quality of life in patients with stable established RA.

Methods

In total, 50 RA patients with moderate disease activity are randomized to receive initially either a portfolio diet based on several food items with suggested anti-inflammatory effects or a control diet during 2 × 10 weeks with 3 months wash-out between diets. Food bags are delivered weekly by a home food delivery chain and referred to as the fiber bag and the protein bag, respectively, to partially blind participants. Both groups continue with regular pharmacological treatment. Known food biomarkers will be analyzed to measure intervention compliance. Impact on disease severity (measured by DAS28, a composite score which predicts disability and progression of RA), risk markers for cardiovascular disease and quality of life are evaluated after each diet regimen. Metabolomics will be used to evaluate the potential to predict responders to dietary treatment. A health economic evaluation is also included.

Discussion

The nutritional status of patients with RA often is poor and many ask their physician for diet advice. No evidence-based dietary guidelines for patients with RA exist because of the paucity of well-conducted sufficiently large diet intervention trials. ADIRA is an efficacy study and will provide evidence as to whether dietary treatment of RA can reduce disease activity and improve quality of life as well as reduce individual and societal costs.

Trial registration

ClinicalTrials.gov Registration Number: NCT02941055.

Electronic supplementary material

The online version of this article (10.1186/s12937-018-0354-x) contains supplementary material, which is available to authorized users.

Evaluation in terms of dietary habits of rheumatic process: A clinical study

OBJECTIVE

This study compared the dietary habits of patients with ankylosing spondylitis (AS) and rheumatoid arthritis (RA).

METHODS

The nutritional status of 56 patients, seen at the Rheumatology Outpatient Clinic and diagnosed with RA based on the ACR-2010 criteria, was compared with that of 28 patients diagnosed with AS using the modified New York criteria. Nutritional status was determined using a form that was filled out during face-to-face interviews with all patients. Patient demographics, disease activity, smoking and alcohol use, concomitant diseases, disease duration and nutritional status were determined using a questionnaire.

RESULTS

RA patients consumed butter on 2 days a week, and AS patients on 1 day per month. Yoghurt was consumed by RA patients daily and by AS patients 3 days a week.

CONCLUSIONS

Compared to the diet of AS patients, the diet of RA patients was richer in protein and lipids. The impact of diet on these two diseases remains to be determined in large-scale studies.

Relationship between leptin concentrations and disease activity in patients with rheumatoid arthritis

BACKGROUND AND OBJECTIVE

Multiple studies have found a direct relationship between leptin concentrations and disease activity in rheumatoid arthritis.

PATIENTS AND METHODS

We studied 77 patients with the diagnosis of rheumatoid arthritis; the leptin determination was through an enzyme immunoassay. Disease activity was assessed by the DAS-28 CRP. A multivariate logistic regression model was used to determine the association between significant variables and leptin concentrations.

RESULTS

40.3% of the patients were in remission, 41.6% were mildly active, 11.7% were moderately active and 6.5% were severely active. The results show an independent association between higher concentrations of leptin and disease activity (OR 1.7; 95% CI 1.4-3.2; p .03), the number of swollen joints (OR 4.6; 95% CI 1.7-8.3; p .000), the number of painful joints (OR 3.4; 95% CI 1.6-4.6; p .000), and the presence of metabolic syndrome (OR 1.3; 95% IC 1.2-1,9; p .045).

CONCLUSION

The data suggest that serum leptin is elevated in patients with active RA.

Intake of ω-3 polyunsaturated fatty acids in patients with rheumatoid arthritis: A systematic review and meta-analysis

OBJECTIVES

Rheumatoid arthritis (RA) is a chronic, autoimmune inflammatory disease of multiple joints that puts the patient at high risk for developing cardiovascular diseases (CVDs). The aim of the present study was to conduct an up-to-date systematic review and meta-analysis of published randomized controlled trials (RCTs) to assess potential changes in RA disease activity, inflammation, and CVD risk after oral intake of ω-3 polyunsaturated fatty acids.

METHODS

Publications up to July 31, 2016 were examined using the PubMed, SCOPUS, and EMBASE databases.

INCLUSION CRITERIA

English language; human subjects; both sexes; RCTs; oral intake of ω-3 fatty acids; minimum duration of 3 mo; and no medication change throughout intervention. The Cochrane Risk of Bias tool was used to assess quality of trials. We included 20 RCTs, involving 717 patients with RA in the intervention group and 535 RA patients in the control group.

RESULTS

Despite the evidence of overall low quality of trials, consumption of ω-3 fatty acids was found to significantly improve eight disease-activity-related markers. Regarding inflammation, only leukotriene B4 was reduced (five trials, standardized mean difference [SMD], -0.440; 95% confidence interval [CI], -0.676 to -0.205; I² = 46.5%; P < 0.001). A significant amelioration was found for blood triacylglycerol levels (three trials, SMD, -0.316; 95% CI, -0.561 to -0.070; I² = 0.0%; P = 0.012).

CONCLUSION

The beneficial properties of ω-3 polyunsaturated fatty acids on RA disease activity confirm the results of previous meta-analyses. Among five proinflammatory markers evaluated, only leukotriene B4 was found to be reduced. However, a positive effect on blood lipid profile of patients with RA was evident, perhaps for the first time.

Oxidative Stress Relevance in the Pathogenesis of the Rheumatoid Arthritis: A Systematic Review

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease whose pathogenic mechanisms remain to be elucidated. The oxidative stress and antioxidants play an important role in the disease process of RA. The study of oxidants and antioxidants biomarkers in RA patients could improve our understanding of disease pathogenesis; likely determining the oxidative stress levels in these patients could prove helpful in assessing disease activity and might also have prognostic implications. To date, the usefulness of oxidative stress biomarkers in RA patients is unclear and the evidence supporting them is heterogeneous. In order to resume and update the information in the status of oxidants and antioxidants and their connection as biomarkers in RA, we performed a systematic literature search in the PubMed database, including clinical trials published in the last five years using the word combination "rheumatoid arthritis oxidative stress". In conclusion, this review supports the fact that the oxidative stress is an active process in RA pathogenesis interrelated to other better known pathogenic elements. However, some controversial results preclude a definite conclusion.

Association between body composition and disease activity in rheumatoid arthritis. A systematic review

BACKGROUND

Reports regarding the association between body composition and inflammatory activity in rheumatoid arthritis (RA) have consistently yielded contradictory results.

OBJECTIVE

To perform a systematic review on the association between overweight/obesity and inflammatory activity in RA.

METHODS

FAST approach: Article search (Medline, EBSCO, Cochrane Library), followed by abstract retrieval, full text review and blinded assessment of methodological quality for final inclusion. Because of marked heterogeneity in statistical approach and RA activity assessment method, a meta-analysis could not be done. Results are presented as qualitative synthesis.

RESULTS

One hundred and nineteen reports were found, 16 of them qualified for full text review. Eleven studies (8,147 patients; n range: 37-5,161) approved the methodological quality filter and were finally included. Interobserver agreement for methodological quality score (ICC: 0.93; 95% CI: 0.82-0.98; P<.001) and inclusion/rejection decision (k 1.00, P>.001) was excellent. In all reports body composition was assessed by BMI; however a marked heterogeneity was found in the method used for RA activity assessment. A significant association between BMI and RA activity was found in 6 reports having larger mean sample size: 1,274 (range: 140-5,161). On the other hand, this association was not found in 5 studies having lower mean sample size: 100 (range: 7-150).

CONCLUSIONS

The modulation of RA clinical status by body fat mass is suggested because a significant association was found between BMI and inflammatory activity in those reports with a trend toward higher statistical power. The relationship between body composition and clinical activity in RA requires be approached with further studies with higher methodological quality.

Emerging role of leptin in rheumatoid arthritis

Numerous studies have suggested the importance of leptin against autoimmune diseases such as systemic lupus erythematosus (SLE), multiple sclerosis (MS) and psoriasis. To summarize our current understanding of the role of leptin in inflammatory responses and rheumatoid arthritis (RA), a systematic review was conducted to assess the discrepancy of leptin in RA and its effect on immunity according to different studies. Recently, emerging data have indicated that leptin is involved in the pathological function of RA, which is common in autoimmune disorders. This review discusses the possible consequences of leptin levels in RA. Blocking the key signal pathways of leptin and inhibiting the leptin activity-like leptin antagonist may be a promising way for potential therapeutic treatment of RA at risk of detrimental effects. However, leptin was increased in patients with RA and may also regulate joint damage. Thus, more understanding of the mechanism of leptin in RA would be advantageous in the future.

Identification of clinical parameters associated with serum oxidative stress in patients with rheumatoid arthritis

OBJECTIVES

Reactive oxygen species (ROS) are considered to be involved in the pathobiology of rheumatoid arthritis (RA); however, their association with disease activity has not been elucidated. In this study, we measured reactive oxygen metabolites (ROM) in patients with RA using a new Free Radical Analytical System and determined clinical parameters associated with ROM.

METHODS

One hundred and fifty-two patients with RA and 80 patients with diabetes mellitus (DM) were included in this observational study. To measure ROM, the d-ROM test was performed on blood samples drawn from all subjects. The correlation between ROM and biomarkers, disease activity, doses of methotrexate (MTX), and prednisolone (PSL) were investigated.

RESULTS

There were significant, positive correlations between ROM and CRP, matrix metalloproteinase 3 (MMP3), Disease Activity Score 28-erythrocyte sedimentation rate (DAS28-ESR), Clinical Disease Activity Index (CDAI), and the Simplified Disease Activity Index (SDAI). Multiple regression analysis revealed that CRP and DAS28-ESR were correlated with ROM.

CONCLUSIONS

The serum level of ROM was associated with CRP and DAS28-ESR, suggesting that ROM, in conjunction with CRP and MMP3, may be able to be used as a new biological disease marker to evaluate the disease activity of RA.

The association between n-3 polyunsaturated fatty acid levels in erythrocytes and the risk of rheumatoid arthritis in Korean women

BACKGROUND

Rheumatoid arthritis (RA) is one of the most common autoimmune diseases that result in chronic inflammation of the joints. n-3 polyunsaturated fatty acids (PUFAs) have been suggested to play a role in the pathogenesis and clinical course of RA. The purpose of the present study was to investigate whether erythrocyte levels of n-3 PUFA are associated with an increased risk of RA and whether this could potentially serve as an indicator of RA disease activity in Korean women.

METHODS

A total of 100 female RA patients and 100 healthy women were enrolled into this study. Erythrocyte fatty acid composition and RA disease activity were evaluated in all patients.

RESULTS

Erythrocyte levels of α-linolenic acid (ALA; 18:3n3), eicosapentaenoic acid (EPA; 20:5n3), and the omega-3 index [EPA + docosahexaenoic acid (DHA)] were significantly lower in RA patients than in healthy controls. Multivariable-adjusted regression analysis showed that the levels of ALA, EPA, and the ratio of EPA to arachidonic acid were negatively associated with the risk of RA after adjusting for body weight and smoking status. Additionally, the concentration of prostaglandin E2 was significantly decreased with increased levels of erythrocyte DHA among RA patients.

CONCLUSIONS

Erythrocyte levels of EPA and ALA were negatively associated with the risk of RA in Korean women, which may be related to eicosanoid metabolism.

Functional profiling of the gut microbiome in disease-associated inflammation

The microbial residents of the human gut are a major factor in the development and lifelong maintenance of health. The gut microbiota differs to a large degree from person to person and has an important influence on health and disease due to its interaction with the human immune system. Its overall composition and microbial ecology have been implicated in many autoimmune diseases, and it represents a particularly important area for translational research as a new target for diagnostics and therapeutics in complex inflammatory conditions. Determining the biomolecular mechanisms by which altered microbial communities contribute to human disease will be an important outcome of current functional studies of the human microbiome. In this review, we discuss functional profiling of the human microbiome using metagenomic and metatranscriptomic approaches, focusing on the implications for inflammatory conditions such as inflammatory bowel disease and rheumatoid arthritis. Common themes in gut microbial ecology have emerged among these diverse diseases, but they have not yet been linked to targetable mechanisms such as microbial gene and genome composition, pathway and transcript activity, and metabolism. Combining these microbial activities with host gene, transcript and metabolic information will be necessary to understand how and why these complex interacting systems are altered in disease-associated inflammation.

Analysis of adipose tissues and stromal vascular cells in a murine arthritis model

PURPOSE

Changes in body composition in rheumatoid arthritis (RA), including a reduction in skeletal muscle mass and the accumulation of visceral fat, have been identified, and the interaction between immune abnormality and metabolic disorders has received much attention. The effect of a high-fat (HF) diet and the role of adipose tissue in an arthritis model were investigated.

METHODS

The effect of an HF diet on the histopathology of joints in murine type II collagen-induced arthritis (CIA) was evaluated. The morphology and adipokine production of adipose tissues were analyzed, and macrophages in the stromal vascular fraction (SVF) were counted by flow cytometry. Serum adipokine levels were measured by ELISA.

RESULTS

Significant exacerbation of joint destruction and aggravated pathological conditions were observed in CIA mice that were fed an HF diet. However, the boundary length of adipose tissue tended to decrease and the levels of adipokines (leptin and adiponectin) were lowered by the induction of arthritis. In HF/CIA mice, nevertheless, the production of MCP-1 in adipose tissues and the accumulation of macrophages in the SVF were significantly higher than CON/CIA group. The serum leptin/adiponectin (L/A) ratio was positively correlated with the number of macrophages in the SVF and MCP-1 production by adipose tissue, particularly in the CIA group.

CONCLUSION

Functional alterations of adipose tissues could be originated from HF diet during developing arthritis. An abnormal activation of macrophages and an increased production of MCP-1 in adipose tissues might be both involved in joint destruction and inflammation.