Rheumatoid cachexia and cardiovascular disease. Nat Rev Rheumatol. 2010;6:445-451. [PMID: 20647995 DOI: 10.1038/nrrheum.2010.105]

Body composition and serum levels of adiponectin, vascular endothelial growth factor, and interleukin-6 in patients with rheumatoid arthritis

Aim

To investigate differences in body composition and body mass index (BMI) in patients with rheumatoid arthritis (RA) and their correlations with serum production of adiponectin, interleukin-6 (IL-6), and vascular endothelial growth factor (VEGF).

Methods

The study included 83 patients (age 53 ± 5 years) with RA treated with methotrexate. We determined their BMI, fat mass, and fat-free mass using bioimpedance analysis, and serum concentrations of adiponectin, VEGF, and IL-6 using immunoassay analysis.

Results

Normal BMI was found in 39 (47%), overweight and obesity in 26 (31%), and underweight in 18 (22%) patients. Concentration of adiponectin was lower in overweight/obese patients than in patients with normal BMI (2.1 [0.8-3.9] μg/mL vs 8.9 (7.2-11.3) μg/mL). In underweight patients, it was moderately increased (12.7 [9.3-14.8] μg/mL) and the correlation between the concentrations of adiponectin and IL-6 was positive (r = 0.4; P = 0.01). Concentrations of VEGF and IL-6 were increased in all groups with RA. The overweight/obese group showed a negative correlation between the concentrations of adiponectin and VEGF (r = - 0.34; P = 0.04), a positive correlation between VEGF concentration and fat mass (r = 0.39; P = 0.02), and a negative correlation between adiponectin concentration and fat mass (r = - 0.23; P = 0.02).

Conclusion

Inflammatory and angiogenesis activation was found in RA patients with all types of body composition, but only in those with obesity and overweight there was a direct antagonism between adiponectin and VEGF. Further research is needed to identify possible regimens of metabolic correction in different variations of body composition.

Cardiovascular comorbidities in patients with psoriatic arthritis: a systematic review

OBJECTIVE

Data regarding cardiovascular comorbidity and cardiovascular risk factors in patients with psoriatic arthritis (PsA) are limited. To evaluate the cardiovascular risk profile, a systematic literature search was performed to provide an extensive summary of all studies available on cardiovascular risk in PsA.

METHODS

Medline, EMBASE and the Cochrane library were searched from January 1966 to April 2011 for English language articles on data concerning cardiovascular diseases and cardiovascular risk factors in PsA. Review articles, case reports and studies on psoriasis alone were excluded.

RESULTS

Twenty-eight articles were included in this review. Studies on all-cause mortality revealed mixed results. Available data on cardiovascular disease appeared more consistent, indicating an increased cardiovascular mortality and morbidity in PsA. Commensurate with this, surrogate markers of subclinical atherosclerosis, arterial stiffness and cardiovascular risk factors, for example hypertension, dyslipidaemia, obesity and metabolic-related factors, were more prominent in PsA compared with controls. Suppression of inflammation was linked with a favourable effect on cardiovascular surrogate markers, for example carotid intima media thickness and endothelial dysfunction, in several (un)controlled studies.

CONCLUSION

Most studies point towards an increased cardiovascular risk in PsA, broadly on a par with the risk level in rheumatoid arthritis, emphasising the need for similar cardiovascular risk management in both conditions. Further studies are needed to indicate whether inflammatory suppression or modification of traditional cardiovascular risk factors, or both, will reduce cardiovascular risk.

Metabolomics--a novel window into inflammatory disease

Inflammation is an important component of normal responses to infection and injury. However, chronic activation of the immune system, due to aberrant responses to normal stimuli, can lead to the establishment of a persistent inflammatory state. Such inflammatory conditions are often debilitating, and are associated with a number of important co-morbidities including cardiovascular disease. Resting non-proliferative tissues have distinctive metabolic activities and requirements, which differ considerably from those in infiltrating immune cells, which are undergoing proliferation and differentiation. Immune responses in tissues may therefore be modulated by the relative abundance of substrates in the inflamed site. In turn immune cell activity can feed back and affect metabolic behaviour of the tissues, as most clearly demonstrated in cachexia - the loss of cellular mass driven by tumour necrosis factor-alpha (TNF-α) a key mediator of the inflammatory response. Here we discuss the potential for metabolomic analysis to clarify the interactions between inflammation and metabolic changes underlying many diseases. We suggest that an increased understanding of the interaction between inflammation and cellular metabolism, energy substrate use, tissue breakdown markers, the microbiome and drug metabolites, may provide novel insight into the regulation of inflammatory diseases.

Inflammatory arthritis as a novel risk factor for cardiovascular disease

Cardiovascular disease (CVD) comorbidity is a significant issue for the inflammatory arthritides (IA). There is a wealth of mortality studies showing increased cardiovascular mortality in rheumatoid arthritis (RA) and the evidence suggests that the same is likely to be true of psoriatic arthritis (PsA) and ankylosing spondylitis (AS). CVD co-morbidity is due to ischaemic pathologies driven by accelerated atherosclerosis and relates to the increased prevalence and clustering of classical risk factors, which may also be affected by treatments for IA, and their interplay with novel risk factors, namely systemic inflammation. Currently we are unable to quantify the contribution that classical and novel risk factors make to an individuals' CVD risk and specific algorithms need to be developed and validated in RA, PsA and AS to facilitate clinical management. Furthermore, large clinical trials are required to assess the effect of lifestyle modifications, primary prevention strategies and effective immunosuppression on hard CVD endpoints. However, in the meantime, a pragmatic approach should be adopted towards CVD risk management. Consensus opinion has generated guidelines for the management of CVD risk in IA and we discuss the importance of assessing each individual for CVD risk and establishing a system for routine risk factor identification alongside a commitment to treat identified risk factors to specific targets.

Asymmetric dimethylarginine as a surrogate marker of endothelial dysfunction and cardiovascular risk in patients with systemic rheumatic diseases

The last few decades have witnessed an increased life expectancy of patients suffering with systemic rheumatic diseases, mainly due to improved management, advanced therapies and preventative measures. However, autoimmune disorders are associated with significantly enhanced cardiovascular morbidity and mortality not fully explained by traditional cardiovascular disease (CVD) risk factors. It has been suggested that interactions between high-grade systemic inflammation and the vasculature lead to endothelial dysfunction and atherosclerosis, which may account for the excess risk for CVD events in this population. Diminished nitric oxide synthesis—due to down regulation of endothelial nitric oxide synthase—appears to play a prominent role in the imbalance between vasoactive factors, the consequent impairment of the endothelial hemostasis and the early development of atherosclerosis. Asymmetric dimethylarginine (ADMA) is one of the most potent endogenous inhibitors of the three isoforms of nitric oxide synthase and it is a newly discovered risk factor in the setting of diseases associated with endothelial dysfunction and adverse cardiovascular events. In the context of systemic inflammatory disorders there is increasing evidence that ADMA contributes to the vascular changes and to endothelial cell abnormalities, as several studies have revealed derangement of nitric oxide/ADMA pathway in different disease subsets. In this article we discuss the role of endothelial dysfunction in patients with rheumatic diseases, with a specific focus on the nitric oxide/ADMA system and we provide an overview on the literature pertaining to ADMA as a surrogate marker of subclinical vascular disease.

A randomized controlled trial of a cognitive behavioural patient education intervention vs a traditional information leaflet to address the cardiovascular aspects of rheumatoid disease

OBJECTIVES

Cardiovascular disease (CVD) is responsible for 50% of the excess mortality for patients with RA. This study aimed to evaluate a novel 8-week cognitive behavioural patient education intervention designed to effect behavioural change with regard to modifiable CVD risk factors in people with RA.

METHODS

This was a non-blinded randomized controlled trial with a delayed intervention arm. Participants were randomly assigned to receive the cognitive behavioural education intervention or a control information leaflet at a ratio of 1:1. The primary outcome measure was patient's knowledge of CVD in RA; secondary measures were psychological measures relating to effecting behaviour change, actual behaviour changes and clinical risk factors. Data were collected at baseline, 2 and 6 months.

RESULTS

A total of 110 participants consented (52 in the intervention group and 58 in the control group) to participate in the study. At 6 months, those in the intervention group had significantly higher knowledge scores (P < 0.001); improved behavioural intentions to increase exercise (P < 0.001), eat a low-fat diet (P = 0.01) and lose weight (P = 0.06); and lower mean diastolic blood pressure by 3.7 mmHg, whereas the control group's mean diastolic blood pressure increased by 0.8 mmHg. There was no difference between the groups on actual behaviours.

CONCLUSIONS

Patient education has a significant role to play in CVD risk factor modification for patients with RA, and the detailed development of this programme probably contributed to its successful results. It is disappointing that behaviours, as we measured them, did not change. The challenge, as always, is how to translate behavioural intentions into action. Larger studies, powered specifically to look at behavioural changes, are required. Trial registration. National Institute for Health Research, UKCRN 4566.

Anti-tumour necrosis factor alpha therapy improves insulin sensitivity in normal-weight but not in obese patients with rheumatoid arthritis

INTRODUCTION

Insulin resistance (IR), a risk factor for the development of cardiovascular disease, is common among patients with rheumatoid arthritis (RA). Inflammation, and especially tumour necrosis factor alpha (TNFα), has been associated with IR, and the administration of anti-TNFα agents is suggested to improve insulin sensitivity. However obesity, a potent contributor to IR, may limit the beneficial effects of anti-TNFα medication on IR. The aim of this study is to compare the effects of anti-TNFα therapy on IR between normal-weight and obese patients with RA.

METHODS

Patients who were normal-weight with IR (N+IR) or obese with IR (O+IR) and had embarked on anti-TNFα treatment, participated. Assessments included body mass index (BMI), insulin sensitivity (Homeostasis Model Assessment of insulin resistance, HOMA and the Quantitative Insulin sensitivity Check Index, QUICKI), and RA disease characteristics before and following six months of anti-TNFα treatment. Their results were compared to matched (for age, gender, BMI, disease duration and smoking status) normal-weight patients without IR (N-IR) and obese without IR (N-IR), respectively. In total, 32 patients were assessed for this study, with 8 in each group.

RESULTS

Following six months of treatment, disease activity was significantly reduced in all groups (P < 0.05) to a similar extent (P for differences between groups > 0.05 in all cases). In the total population, changes in HOMA (mean reduction at 6 m = -0.2 ± 0.1; P = 0.088) and QUICKI (mean increase at 6 m = 0.03 ± 0.022; P = 0.092) after treatment were not statistically significant, though a trend towards improvement was observed. However, N+IR patients showed a significant decrease in HOMA (mean reduction at 6 m = -0.54 ± 0.2; P = 0.002) and increase in QUICKI (mean increase at 6 m = 0.046 ± 0.02; P = 0.011). These changes were significantly different compared to the other groups (P < 0.05 in all cases). Multivariable analyses showed that the change in Erythrocyte Sedimentation Rate (ESR), and the change in C-Reactive Protein (CRP) associated with the improvement in HOMA (ESR: F₁₋₇ = 5.143, P = 0.019; CRP: F₁₋₇ = 3.122, P = 0.022) and QUICKI (ESR: F₁₋₇ = 3.814, P = 0.021; CRP: F₁₋₇ = 2.67; P = 0.041) only in the N+IR group.

CONCLUSIONS

Anti-TNFα therapy, through controlling inflammation, seems to improve insulin sensitivity in normal-weight RA patients with insulin resistance, but is not sufficient to achieving the same beneficial effect in obese RA patients with insulin resistance.

TNF-Alpha in the Locomotor System beyond Joints: High Degree of Involvement in Myositis in a Rabbit Model

The importance of TNF-alpha in arthritis is well documented. It may be that TNF-alpha is also markedly involved in muscle inflammation (myositis). An animal model where this can be investigated is needed. A newly developed rabbit myositis model involving pronounced muscle overuse and local injections of substances having proinflammatory effects was therefore used in the present study. The aim was to investigate the patterns of TNF-alpha expression in the developing myositis and to evaluate the usefulness of this myositis model for further TNF-alpha research. Human rheumatoid arthritis (RA) synovial tissue was examined as a reference. TNF-alpha immunoexpression and TNF-alpha mRNA, visualized via in situ hybridization, were detected in cells in the inflammatory infiltrates of the affected muscle (soleus muscle). Coexistence of TNF-alpha and CD68 immunoreactions was noted, suggesting that the TNF-alpha reactive cells are macrophages. Expression of TNF-alpha mRNA was also noted in muscle fibers and blood vessel walls in areas with inflammation. These findings demonstrate that TNF-alpha is highly involved in the myositis process. The model can be used in further studies evaluating the importance of TNF-alpha in developing myositis.

Predictors of new atherosclerotic carotid plaque development in patients with rheumatoid arthritis: a longitudinal study

Introduction

Rheumatoid arthritis (RA) is associated with increased cardiovascular morbidity and mortality attributed to both classical risk factors and chronic inflammation. We assessed longitudinally the factors associated with new carotid plaques in nondiabetic RA patients and apparently healthy individuals.

Methods

In our present prospective observational study, carotid plaques were identified by ultrasonography at baseline and follow-up end, separated by an average of 3.6 ± 0.2 years, in 64 patients (mean age 59.2 ± 12.0 and disease duration at baseline 7.8 ± 6.2 years, 83% women, clinical and laboratory evaluation every 3 to 6 months). In a substudy, 35 of the patients were matched 1:1 for traditional cardiovascular risk factors with 'healthy' controls and were studied in parallel.

Results

New atherosclerotic plaques formed in 30% of patients (first plaque in 9%) who were significantly older than the remaining patients. Tobacco use, blood pressure, body mass index, average cumulative low-density lipoprotein, high-sensitivity C-reactive protein, erythrocyte sedimentation rate level, RA stage, functional class, disease duration and treatment modalities during follow-up did not differ significantly between subgroups after application of the Bonferroni correction. RA was in clinical remission, on average, for approximately 70% of the follow-up time and was not different between subgroups. Multivariate analysis including all the above parameters revealed that age (P = 0.006), smoking (P = 0.009) and duration of low-dose corticosteroid use (P = 0.016) associated independently with new plaque formation. RA patients displayed similar numbers of newly formed carotid plaques to the tightly matched for traditional cardiovascular risk factors 'healthy' controls, although more patients than controls had carotid plaques at baseline.

Conclusions

Formation of new atherosclerotic plaques in this small cohort of patients with well-controlled RA depended mainly on traditional cardiovascular risk factors and corticosteroid use, whereas an adverse effect of residual systemic inflammation was not readily detectable.

Are the benefits of a high-intensity progressive resistance training program sustained in rheumatoid arthritis patients? A 3-year followup study

OBJECTIVE

Rheumatoid arthritis (RA) patients were reassessed for body composition and physical function mean ± SD 39 ± 6 months after commencing a randomized controlled trial involving 24 weeks of either high-intensity progressive resistance training (PRT) or low-intensity range of movement exercise (control) to determine whether the benefits of PRT (i.e., reduced fat mass [FM], increased lean mass [LM], and improved function) were retained.

METHODS

Nine PRT and 9 control subjects were reassessed for body composition (dual x-ray absorptiometry) and function (knee extensor strength, chair test, arm curl test, 50-foot walk) approximately 3 years after resuming normal activity following the exercise intervention.

RESULTS

At followup, PRT subjects remained significantly leaner than control subjects (P = 0.03), who conversely had accumulated considerable FM during the study period (approximately -1.0 kg versus +2.4 kg, PRT versus controls). PRT subjects also retained most of the improvement in walking speed gained from training (P = 0.03 versus controls at followup). In contrast, the PRT-induced gains in LM and strength-related function were completely lost. Data from the controls suggest that established and stable RA patients have similar rates of LM loss but elevated rates of FM accretion relative to age-matched sedentary non-RA controls.

CONCLUSION

We found that long-term resumption of normal activity resulted in loss of PRT-induced improvements in LM and strength-related function, but substantial retention of the benefits in FM reduction and walking ability. The relatively long-term benefit of reduced adiposity, in particular, is likely to be clinically significant, as obesity is very prevalent among RA patients and is associated with their disability and exacerbated cardiovascular disease risk.

Rheumatoid arthritis: is it a coronary heart disease equivalent?

PURPOSE OF REVIEW

This review examines current evidence to address the question whether rheumatoid arthritis (RA) is a coronary heart disease equivalent, similar to type 2 diabetes mellitus (DM2).

RECENT FINDINGS

Cross-sectional and longitudinal epidemiological studies show a two-fold higher risk of cardiovascular disease (CVD) in patients with RA, and the magnitude of this increased risk is comparable to the risk associated with DM2. However, the mechanisms responsible for this appear to be different in the two conditions, with RA-related CVD being attributed to 'high-grade' systemic inflammation as well as classical CVD risk factors. Several classical risk factors are affected by RA or its medications, and there are some paradoxical associations between obesity or lipid abnormalities and CVD death in RA.

SUMMARY

Management of RA-related CVD is likely to require both aggressive control of inflammation and systematic screening and management of classical CVD risk factors. It remains unknown whether primary prevention strategies applied successfully in DM2 would be equally easy to implement and demonstrate similar benefits in people with RA.

Long-term effects of anti-tumour necrosis factor therapy on weight in patients with rheumatoid arthritis

In patients with rheumatoid arthritis (RA), weight is an important prognostic factor. Preliminary evidence has indicated that treatment with anti-tumour necrosis factor (TNF) therapy can affect the weight of patients with RA, but the relationship between improved prognosis and weight changes remains to be clarified. Our aim was to investigate the effects of anti-TNF therapy on the weight of patients with RA following 24 months of treatment. Patients (n = 168) were selected for this retrospective analysis on the basis of having received anti-TNF therapy for the first time. Change in body weight after 12 and 24 months of treatment was calculated and analysed by multiple regression analysis using age, sex, baseline body mass index (BMI), baseline DAS28 score, disease-modifying antirheumatic drug use, steroid use and specific anti-TNF drug as explanatory variables. The mean weight change of the patient group after 12 months of treatment was +1.58 kg (95% CI 0.71 to 2.46 kg) and after 24 months was +1.80 kg (95% CI 0.69 to 2.67 kg). After 24 months, 64.3% of patients had gained weight. There was no statistically significant association between weight gain at 12 or 24 months and age, sex, steroid use at baseline, anti-TNF drug or baseline DAS28 score. Baseline BMI had a statistically significant negative association with weight gain at 12 and 24 months. RA patients with lower BMIs tend to gain weight with anti-TNF therapy. Further studies are required to determine if the weight gained is fat and/or muscle and the effects upon general health outcomes.

Cardiovascular disease in rheumatoid arthritis: state of the art and future perspectives

Rheumatoid arthritis is associated with an increased risk for cardiovascular events, such as myocardial infarction and stroke. Epidemiological evidence suggests that classic cardiovascular risk factors, such as hypertension, dyslipidaemia, insulin resistance and body composition alterations are important but not sufficient to explain all of the excess risk. High-grade systemic inflammation and its interplay with classic risk factors may also contribute. Some associations between classic risk factors and cardiovascular risk in people with rheumatoid arthritis appear counterintuitive but may be explained on the basis of biological alterations. More research is necessary to uncover the exact mechanisms responsible for this phenomenon, develop accurate systems used to identify patients at high risk, design and assess prevention strategies specific to this population of patients.