Rheumatoid cachexia and cardiovascular disease

OBJECTIVE

It has been frequently stated that rheumatoid cachexia (RC) associates with increased cardiovascular risk; however, no studies to date have investigated this. The aim of this study was to investigate the association of RC with multiple novel and classical cardiovascular disease (CVD) risk factors and the presence of established CVD in rheumatoid arthritis (RA).

METHODS

A total of 34 RA patients with RC (RA+RC) were identified from a database of 400 RA patients using published RC criteria and compared to the remaining patients (RA-RC) who did not fulfil RC criteria. All patients were assessed for fat and fat-free mass, albumin (indicator of catabolism), disease activity/severity, novel and classical risk CVD factors and established CVD.

RESULTS

Fat-free mass (kg) and albumin (g/L) were significantly decreased in RA+RC vs. RA-RC patients: 37.3(33.9-41.6) vs. 45.9(41.2-55.5), p<0.001 and 39.6 + or - 6.7 vs. 42.4 + or - 4.9, p=0.001). Percent body fat was not significantly different. No significant differences were detected in either the classical or novel CVD risk factors, 10-year CVD risk or the prevalence of established CVD.

CONCLUSIONS

RC does not appear to be associated with worse CVD profile in RA patients, but this needs to be confirmed in prospective studies.

What predicts obesity in patients with rheumatoid arthritis? An investigation of the interactions between lifestyle and inflammation

OBJECTIVE

To assess whether physical activity, diet or inflammation is a more important determinant of body mass index (BMI) and body fat (BF) in patients with rheumatoid arthritis (RA).

METHODS

A total of 150 RA patients (102 female) were assessed for BMI and BF. Their habitual physical activity was assessed with the international physical activity questionnaire (IPAQ) and their energy intake with a 3-day food diary. Pro-inflammatory cytokines (interleukins, IL-1 and IL-6, and tumor necrosis factor-alpha), erythrocyte sedimentation rate, C-reactive protein, disease activity score-28 and physical function (Health Assessment Questionnaire-HAQ) were also measured.

RESULTS

BMI correlated inversely with IPAQ (r=-0.511, P=0.000) and positively with energy intake (r=0.331, P=0.016) and HAQ (r=0.133, P=0.042). BF correlated inversely with IPAQ (r=-0.575, P=0.000) and positively with HAQ (r=0.201, P=0.037). Normal weight patients were more physically active compared with those who were either overweight (P=0.006) or obese (P=0.000). Underweight patients consumed significantly fewer calories compared with other patients (P<0.05 in all cases). Cytokines or HAQ did not differ between weight groups. IPAQ was the sole predictor of obesity, whereas energy intake was the sole predictor of underweight.

CONCLUSIONS

Inflammation does not seem to influence BMI and BF in RA. As in the general population, high levels of habitual physical activity associate with low BMI and BF in RA. Energy intake is a major determinant of being underweight in those who consume fewer calories. Further research is needed to investigate the suitability of exercise and diet modalities, and their effects on the body composition of RA patients.

Reactions to disability in patients with early versus established rheumatoid arthritis

OBJECTIVES

This study examined differences in reactions to disability between early and established rheumatoid arthritis (RA) patients, and whether these reactions were related to age, physical functioning, acceptance of illness, or self-efficacy.

METHODS

Thirty-four patients with early RA (< 2 years since diagnosis) and 84 patients with established RA (> 4 years since diagnosis) completed the Reactions to Impairment and Disability Inventory (RIDI), and measures of anxiety, depression, acceptance of illness, self-efficacy, and physical functioning.

RESULTS

Early RA patients reported greater future denial than established RA patients. Younger patients reported more hostility than older patients. Accepting the illness was uniquely related to less anger and hostility. Higher self-efficacy for pain specifically related to greater shock, while patients with poorer self-efficacy for other symptoms reported worse anxiety, depression, shock, and anger.

CONCLUSIONS

Denial may be a coping strategy in the early stages of RA: anxiety, depression, shock, and anger appear to persist. Longitudinal studies of RA patients from diagnosis are required to plan interventions timed to maximize patient benefit and optimize healthcare resource utilization.

Influence of Acetylator Status on Sulphasalazine Efficacy and Toxicity in Patients with Rheumatoid Arthrftis

The influence of acetylator status on the therapeutic efficacy and the toxicity of sulphasalazine (SASP) was assessed in 106 patients with rheumatoid arthritis (RA). Changes of indices of disease activity after 6 months, and progression of erosions after 2 years of SASP treatment were similar in fast and slow acetylators. Incidence and nature of withdrawals and side-effects, and requirement for intra-articular steroid injections or combination therapy due to poor response to SASP were almost identical in the two groups. A significant increase of the hepatic enzyme aspartate transaminase was noted mainly in slow acetylators, but was not associated with clinical disease. These results suggest that acetylator status does not relate significantly to either the efficacy or the toxicity of SASP in RA. It is possible that hepatic metabolism is affected by SASP, particularly in slow acetylators, but this does not lead to clinically identifiable problems.

Cardiovascular risk factors and not disease activity, severity or therapy associate with renal dysfunction in patients with rheumatoid arthritis

OBJECTIVES

The present study aimed to evaluate the prevalence and associations of renal dysfunction in patients with rheumatoid arthritis (RA). It specifically addressed the hypotheses that renal dysfunction in these patients may associate with the presence of insulin resistance, dyslipidaemia, uric acid levels and/or current levels of systemic inflammation.

METHODS

Renal function was assessed by estimated glomerular filtration rate (GFR) using the modification of diet in renal disease equation in 400 consecutive RA patients for this cross-sectional, single-centre study. Risk factors for renal dysfunction were recorded/measured in all participants. Correlations between GFR and other variables were analysed by Pearson or Spearman test as appropriate. Linear regression was used to test the independence of the associations between GFR and other variables.

RESULTS

In this RA patient cohort, 67.75% of patients had a reduced GFR of less than 90 ml/minute per 1.73 m(2) and 12.75% had a GFR of less than 60 ml/minute per 1.73 m(2). Multivariable analysis revealed significant associations between GFR and age (beta = -0.370, p<0.001), female sex (beta = -0.181, p=0.002), total cholesterol (beta = -0.112, p=0.022), serum uric acid (SUA) (beta = -0.425, p<0.001) and the presence of extra-articular disease, apart from sicca and/or nodules (beta = -0.084, p=0.040).

CONCLUSIONS

Renal dysfunction in RA is quite common and associates with classic cardiovascular risk factors such as advanced age and dyslipidaemia, levels of SUA and the presence of extra-articular disease. Renal dysfunction was not related to other RA-related factors including disease activity and duration, disability and past or present use of nephrotoxic medications.

Transforming growth factor-beta1 869T/C, but not interleukin-6 -174G/C, polymorphism associates with hypertension in rheumatoid arthritis

OBJECTIVES

Part of the deleterious effects of systemic inflammation on the cardiovascular system of patients with RA may be exerted via increased propensity to hypertension. IL-6 and TGF-beta1 are important regulators of the inflammatory response. In some, but not all, studies, IL6 -174G/C (rs1800795) and TGFB1 869T/C (rs1982073) gene polymorphisms have been associated with hypertension in the general population. The present study addressed their potential association with hypertension in RA patients.

METHODS

TGFB1 869T/C and IL6 -174G/C were identified in 400 RA patients and 422 local, non-RA controls using real-time PCR and melting curve analysis. Binary logistic and linear regression models were used to identify the independence of the effects of the polymorphisms on hypertension.

RESULTS

Genotypic and allelic frequencies of the two polymorphisms were similar in RA and controls. Within the RA group, there was no significant association between IL6 -174G/C and hypertension, but TGF 869T-allele carriers had significantly increased prevalence of hypertension compared with CC homozygotes (70.2 vs 55.2%; P = 0.023). This association remained significant after adjustment for other hypertension risk factors and medication (odds ratio = 1.96; 95% CI 1.02, 3.77; P = 0.044), and was more pronounced in patients with increased systemic inflammation.

CONCLUSIONS

This study suggests an association of TGFB1 869T/C, but not of IL6 -174G/C, with hypertension in RA patients. If this finding is confirmed in prospective studies, this polymorphism could be used as a screening tool for RA patients with higher risk of developing hypertension and lead to increased surveillance and earlier treatment.

Associations of obesity with modifiable risk factors for the development of cardiovascular disease in patients with rheumatoid arthritis

OBJECTIVES

To assess the association of body mass index (BMI) with modifiable cardiovascular disease (CVD) risk factors in patients with rheumatoid arthritis (RA).

METHODS

BMI, disease activity, selected CVD risk factors and CVD medication were assessed in 378 (276 women) patients with RA. Patients exceeding accepted thresholds in >or=3 CVD risk factors were classified as having the metabolic syndrome (MetS).

RESULTS

BMI independently associated with hypertension (OR = 1.28 (95% CI = 1.22 to 1.34); p = 0.001), high-density lipoprotein (OR = 1.10 (95% CI = 1.06 to 1.15); p = 0.025), insulin resistance (OR = 1.13 (95% CI = 1.08 to 1.18); p = 0.000) and MetS (OR = 1.15 (95% CI = 1.08 to 1.21); p = 0.000). In multivariable analyses, BMI had the strongest associations with CVD risk factors (F(1-354) = 8.663, p = 0.000), and this was followed by lipid-lowering treatment (F(1-354) = 7.651, p = 0.000), age (F(1-354) = 7.541, p = 0.000), antihypertensive treatment (F(1-354) = 4.997, p = 0.000) and gender (F(1-354) = 4.707, p = 0.000). Prevalence of hypertension (p = 0.004), insulin resistance (p = 0.005) and MetS (p = 0.000) was significantly different between patients with RA who were normal, overweight and obese, and BMI differed significantly according to the number of risk factors present (p = 0.000).

CONCLUSIONS

Increasing BMI associates with increased CVD risk independently of many confounders. RA-specific BMI cut-off points better identify patients with RA at increased CVD risk. Weight-loss regimens should be developed and applied in order to reduce CVD in patients with RA.

Hypertension in rheumatoid arthritis

RA associates with an increased burden of cardiovascular disease, which is at least partially attributed to classical risk factors such as hypertension (HT) and dyslipidaemia. HT is highly prevalent, and seems to be under-diagnosed and under-treated among patients with RA. In this review, we discuss the mechanisms that may lead to increased blood pressure in such patients, paying particular attention to commonly used drugs for the treatment of RA. We also suggest screening strategies and management algorithms for HT, specific to the RA population, although it is clear that these need to be formally assessed in prospective randomized controlled trials designed specifically for the purpose, which, unfortunately, are currently lacking.

Polypharmacy among people with rheumatoid arthritis: the role of age, disease duration and comorbidity

BACKGROUND

People with rheumatoid arthritis (RA) often have comorbidities with associated disability and complex medication regimens. Little published evidence exists about why people with RA require so many medications, although it is logical to hypothesize that this may relate to older age, longer duration of RA, more active RA, worse functional disability and a greater number of comorbidities.

OBJECTIVES

We set out to quantify polypharmacy in RA and identify its predictors in an observational cohort.

METHODS

The case notes of 348 people receiving secondary care for RA were reviewed to record polypharmacy. The 28-joint Disease Activity Score (DAS28) was calculated and the Health Assessment Questionnaire (HAQ) and the Self-administered Comorbidity Questionnaire (SCQ) were completed.

RESULTS

The mean total number of medications was 5.39, with a maximum of 16; of these, a mean of 2.41 medications were directly for RA. A mediational relationship was identified: older age and longer RA duration were significant predictors of a greater total number of medications, but these relationships were explained by the greater number of comorbidities in older participants and those with longer RA duration. Polypharmacy was not related to RA activity or functional disability.

CONCLUSIONS

Polypharmacy is common among people with RA and associates with older age and longer RA duration through a greater number of comorbidities. Regular review of the full treatment plan of individuals with RA by pharmacists and other health professionals specializing in rheumatology, to weigh the benefits and risks of each medication and their interactions in light of RA activity and comorbidities, is advocated.

Measuring fatigue among women with Sjögren's syndrome or rheumatoid arthritis: a comparison of the Profile of Fatigue (ProF) and the Multidimensional Fatigue Inventory (MFI)

BACKGROUND

Fatigue is common in both Sjögren's syndrome (SS) and rheumatoid arthritis (RA) and can restrict functioning.

AIMS

We tested the convergent validity of the Profile of Fatigue (ProF) using the Multidimensional Fatigue Inventory (MFI) in SS and RA.

METHODS

The 16-item ProF and the 20-item MFI were completed by 82 White-British women aged 35-79 years (mean 60.4 years). Thirty-four had been diagnosed with SS for a mean of 7.0 years and 48 had been diagnosed with RA for a mean of 14.5 years. The ProF measures four somatic facets of fatigue and two mental facets; the MFI contains one mental and four somatic facets. The structures of the items from both measures were tested by principal component factor analysis using varimax rotation.

RESULTS

No significant differences in fatigue were found between the women with SS or RA. Five factors explained a total of 76% of the variance of the MFI; six factors explained 94% of the variance of the ProF. Mental fatigue items from both questionnaires loaded onto separate factors from somatic fatigue items; the two original facets of mental fatigue in the ProF were replicated. The four somatic fatigue facets of the ProF were generally replicated but the somatic facets of the MFI did not replicate as clearly. Equivalent facets correlated well between the two questionnaires (r >or= 0.65).

CONCLUSIONS

Both the ProF and the MFI distinguish between somatic and mental fatigue in SS and RA but the ProF appears better at resolving somatic facets of fatigue.

New resting energy expenditure prediction equations for patients with rheumatoid arthritis

OBJECTIVES

Resting energy expenditure (REE), one of the main components of total energy expenditure, can be measured via indirect calorimetry and/or predicted from equations. The latter may be misleading in RA, as they do not take into account the metabolic alterations occurring in RA. The objectives of this study are to evaluate the accuracy of widely used REE-predictive equations in RA patients against measured REE and to develop RA-specific equations.

METHODS

We assessed REE (via indirect calorimetry and several predictive equations), fat-free mass (FFM; via bioelectrical impedance) and disease activity (CRP) in RA patients and healthy controls. Data from 60 RA patients (experimental group) were used to assess the accuracy of existing REE equations and to develop new equations. The new equations were validated in an independent cross-validation group of 22 RA patients. These two groups were merged and two final equations were developed.

RESULTS

All equations significantly under-predicted measured REE (from 15% to 18.2%, all at P < 0.001) in the RA experimental group, but not in the control group. After both equations demonstrated a high validity in the cross-validation group, the new final REE prediction equations developed from the total RA sample (n = 82) were: Model 1: REE (kcal/day) = 126.1 x FFM(0.638) x CRP(0.045) (R(2) = 0.70) and Model 2: REE (kcal/day) = 598.8 x weight(0.47) x age(-0.29) x CRP(0.066) (R(2) = 0.62).

CONCLUSION

The new equations provide an accurate prediction of REE in RA patients and could be used for clinical monitoring of resting metabolism of these patients without the requirement for specialized personnel.

Lymphotoxin 252A>G polymorphism is common and associates with myocardial infarction in patients with rheumatoid arthritis

OBJECTIVE

Cardiovascular disease (CVD) is more prevalent and more likely to lead to death in patients with rheumatoid arthritis (RA). Single nucleotide polymorphisms of the genes for lymphotoxin-A (LT-A) and its regulatory protein galectin-2 (LGALS2) have been implicated as genetic risk factors for acute cardiovascular events in the general population: we hypothesised that their risk alleles/genotypes (a) may be more frequent among patients with RA compared with non-RA controls (thus explaining some of the increased CVD in RA), and (b) may be more frequent among patients with RA with prevalent CVD compared with patients with RA without CVD.

METHODS

Genomic DNA samples were collected from 388 patients with RA and 399 local population controls without RA. LT-A gene intron 1 252A>G and LGALS2 intron 1 3279C>T single nucleotide polymorphisms were identified using real-time polymerase chain reaction and melting curve analysis.

RESULTS

LT-A 252GG homozygotes were significantly more prevalent among patients with RA compared with controls (19.8% vs 11.8%, p = 0.002; OR(GG/GA,AA) = 1.85, 95% CI 1.25 to 2.75, p = 0.002). Patients with RA possessing LT-A 252 GG were significantly more likely to have had a myocardial infarction compared with those with LT-A 252 AA or GA (13% vs 5.5%, p = 0.02; adjusted OR(GG/GA,AA) = 3.03, 95% CI 1.2 to 7.68, p = 0.002). The frequency of LGALS2 polymorphisms was similar between RA and controls and was not associated with CVD among patients with RA.

CONCLUSIONS

The LT-A 252GG genotype occurs more frequently among patients with RA than the general population. In RA, this genotype appears to associate with increased likelihood of suffering an myocardial infarction.

Blockade of tumour necrosis factor-alpha in rheumatoid arthritis: effects on components of rheumatoid cachexia

OBJECTIVES

Rheumatoid arthritis (RA) is accompanied by increased resting energy expenditure (REE) and decreased fat-free mass (FFM). This is referred to as rheumatoid cachexia and is attributed to high levels of tumour necrosis factor-alpha (TNF-alpha). This study aimed to investigate the effects of anti-TNF-alpha therapy on REE, body composition, physical activity and protein intake in RA patients.

METHODS

Twenty RA patients [50% female; age: (mean +/- s.d.) 61.1 +/- 6.8 yrs; body mass index (BMI): 28.3 +/- 3.7 kg/m2] and 12 age-sex-BMI-matched healthy controls were assessed. REE (indirect calorimetry), body composition (bioelectrical impedance), the International Physical Activity Questionnaire (IPAQ), diet, Health Assessment Questionnaire (HAQ), disease activity [disease activity score 28 (DAS28), erythrocyte sedimentation rate (ESR), C-reactive protein] and serum TNF-alpha were measured before (Baseline) as well as 2 weeks (Time-1) and 12 weeks (Time-2) after initiation of anti-TNF-alpha treatment. Controls were only assessed at Baseline.

RESULTS

RA patients had significantly higher REE than controls at Baseline (1799.4 +/- 292.0 vs 1502.9 +/- 114.5 kcal/day, P = 0.002). Within the RA group, REE increased significantly between Time-1 and Time-2 (P = 0.001) but not between Baseline and Time-2. Sustained significant increases were observed in IPAQ (P = 0.001) and protein intake (P = 0.001). There were no significant changes in FFM or body fat. ESR (P = 0.002), DAS28 (P < 0.001), HAQ (P < 0.001) and TNF-alpha (P = 0.024) improved significantly. Physical activity (P = 0.001) and protein intake (P = 0.024) were significant between-subject factors for the elevation of REE.

CONCLUSIONS

After 12 weeks of anti-TNF-alpha therapy, there were significant improvements in disease activity and physical function, as well as physical activity and protein intake, but no significant changes in REE or FFM. There is a need for longer-term studies in this field.

Cigarette smoking significantly increases basal metabolic rate in patients with rheumatoid arthritis

OBJECTIVE

Basal metabolic rate (BMR) is the most important indicator of human metabolism and its abnormalities have been linked to undesirable health outcomes. Cigarette smoking associates with increased BMR in healthy individuals; it is also related with worse disease outcomes in patients with rheumatoid arthritis(RA), in whom BMR is high due to hypercatabolism caused by systemic inflammation. We aimed to investigate whether smokers with RA demonstrated higher BMR levels than their non-smoking counterparts.

METHODS

A total of 53 patients with RA (36 female, 17 male, 20 current smokers) were assessed for: BMR(indirect calorimetry), anthropometrical data, fat-free mass (bioelectrical impedance), physical function (health assessment questionnaire; HAQ) and disease activity(disease activity score DAS28 and C reactive protein).

RESULTS

RA smokers and non-smokers were not significantly different for age, height, weight, body mass index and fat-free mass. Compared to non-smokers,smokers with RA demonstrated significantly higher BMR (mean (SD) 1513.9 (263.3) vs 1718.1 (209.2) kcal/day; p,0.001) and worse HAQ (1.0 (0.8) vs 1.7 (0.8); p=0.01). The BMR difference was significantly predicted by the interaction smoking/gender (p=0.04). BMR was incrementally higher in light, moderate and heavy smokers (p=0.018), and correlated with the daily number of cigarettes smoked (r=0.68, p=0.04).

CONCLUSION

Current cigarette smoking further increases BMR in patients with RA and has a negative impact on patients self-reported functional status. Education regarding smoking cessation is needed for the RA population.

Long-term exposure to medium-dose glucocorticoid therapy associates with hypertension in patients with rheumatoid arthritis

OBJECTIVE

Rheumatoid arthritis (RA) associates with increased cardiovascular morbidity and mortality that is due to both traditional and novel cardiovascular risk factors. Hypertension (HT), one of the most common risk factors for cardiovascular disease, is highly prevalent in RA. The effects of long-term glucocorticoid (GC) therapy on blood pressure have not been established yet. This study examined whether GC exposure associates with HT in patients with RA.

METHODS

Four hundred consecutive RA patients with detailed clinical and laboratory assessments were categorized into three groups according to GC exposure: no or limited exposure (N/L-E); a low-dose (< 7.5 mg) long-term exposure (LD/LT-E); and medium-dose (> or = 7.5 mg) long-term exposure (MD/LT-E). The association of GC exposure with HT was evaluated using logistic regression analysis.

RESULTS

HT was more prevalent in the MD/LT-E group (84.7%) than the LD/LT-E or N/L-E groups (70.7 and 67.3%, respectively, P = 0.028). Logistic regression revealed increased odds for HT when comparing MD/LT-E with N/L-E, after adjustment for HT risk factors [odds ratio (OR) = 2.57, 95% CI 1.01-6.56, P = 0.049] and RA disease characteristics (OR = 3.64, 95% CI: 1.36-9.77, P = 0.01).

CONCLUSIONS

MD/LT GC exposure associates with a very high prevalence of HT. This appears to be independent of other risk factors for HT or of channelling bias due to disease severity, even though the latter cannot be excluded given the cross-sectional nature of our study. RA patients in this GC exposure group should be particularly targeted for early identification and aggressive management of HT.