Antonios Stavropoulos-Kalinoglou

Individualised aerobic and resistance exercise training improves cardiorespiratory fitness and reduces cardiovascular risk in patients with rheumatoid arthritis

Background and objectives Low cardiorespiratory fitness (CRF) is a significant predictor of cardiovascular disease (CVD), and interventions aiming at increasing CRF are known to reduce CVD risk. The effects of such interventions on CVD risk have not been studied in patients with rheumatoid arthritis (RA). Methods 40 age, gender, body mass index (BMI) and disease duration matched RA patients were allocated to either an exercise (receiving 6 months individualised aerobic and resistance high intensity exercise intervention, three times per week), or control (receiving advice on exercise benefits and lifestyle changes) arm. Participants were assessed at baseline, 3 and 6 months for aerobic capacity (VO2max), individual CVD risk factors (blood pressure, lipids, insulin resistance, body composition), 10-year CVD event probability and RA characteristics (C-reactive protein (CRP), Disease Activity Score 28 (DAS28) and Health Assessment Questionnaire (HAQ)). Results There were no differences between groups at baseline in any of the assessed variables. VO2max (p=0.001), blood pressure (systolic: p<0.001; diastolic: p=0.003), triglycerides (p=0.030), high density lipoprotein (HDL; p=0.042), total cholesterol:HDL ratio (p=0.005), BMI (p=0.001), body fat (p=0.026), 10-year CVD event probability (p=0.012), CRP (p=0.042), DAS28 (p=0.008) and HAQ (p=0.003) were all significantly improved in the exercise versus the control group. The change in VO2max was the strongest predictor for the observed improvements in all of the assessed CVD risk factors and disease characteristics. Conclusions Individualised aerobic and resistance exercise intervention can lead to significantly improved CRF, individual CVD risk factors, composite CVD risk, and disease activity and severity in RA patients.

Platelet function in rheumatoid arthritis: arthritic and cardiovascular implications

Patients with rheumatoid arthritis (RA) are at high risk of cardiovascular events. Platelet biomarkers are involved in inflammation, atherosclerosis and thrombosis. Cardiovascular and RA-associated factors can alter the structure and function of platelets, starting from megakaryocytopoiesis. Reactive megakaryocytopoiesis increases circulating platelets count and triggers hyperactivity. Hyperactive platelets target synovial membranes with subsequent local rheumatoid inflammation. Hyperactive platelets interact with other cells, and target the vascular wall. Accumulating evidence suggests that disease modifying anti-rheumatic drugs (DMARD) decrease platelet activity.

Association of interleukin-6 (IL-6)-174G/C gene polymorphism with cardiovascular disease in patients with rheumatoid arthritis: The role of obesity and smoking

BACKGROUND Cardiovascular morbidity and mortality are increased in rheumatoid arthritis (RA). Interleukin-6 (IL-6) is high in RA and, together with smoking and obesity, an important contributor to the development of cardiovascular disease (CVD). The present study examined the potential association of IL-6-174 G/C polymorphism, together with obesity and smoking, with the presence of CVD in RA patients. METHODS AND RESULTS DNA samples were collected from 383 RA patients (who also had extensive clinical and laboratory evaluations). IL-6-174 G/C was identified using real time PCR and melting curve analysis. Serum IL-6 levels were measured in a subgroup of 135 RA patients to examine the functionality of the polymorphism. Carriers of the IL6-174C-allele demonstrated increased prevalence of CVD (26.2% vs. 17.0%, p=0.041). There was a significant association with CVD, even after adjustment for traditional CVD risk factors (OR=1.92, 95%CI: 1.03 to 3.58, p=0.041). IL-6 levels were significantly increased in C-allele carriers [14.02 (3.21-38.81) vs. 4.48 (2.25-16.5), p=0.028]. No significant interactions were observed between adiposity and IL6-174G/C genotypes. There was only a trend for an interaction between ever smoking and IL6 C-allele carriers on CVD. CONCLUSION The IL-6-174C-allele may associate with CVD in RA patients and possibly exerts its effect via increased inflammation. This finding, if confirmed in future studies, may be used as a part of a genetic screening tool for RA patients at high CVD risk.

Individualised exercise improves endothelial function in patients with rheumatoid arthritis

Background We investigated the effects of individualised combined resistance and aerobic exercise on microvascular and macrovascular function in rheumatoid arthritis (RA) patients. Methods Forty age-matched, gender-matched and body mass index (BMI)-matched patients were allocated to either an exercise group, receiving a 6 months tailored aerobic and resistance exercise intervention, or controls receiving only information about the benefits of exercise. Participants were assessed for microvascular (acetylcholine (Ach) and sodium nitroprusside (SNP)) and macrovascular (flow-mediated dilatation (FMD) and glyceryl trinitrate (GTN)) endothelial function, maximal oxygen uptake, disease activity and severity (C-reactive protein (CRP), disease activity score 28 and health assessment questionnaire). Data were collected at baseline, 3 months and at the end of the intervention (6 months). Results At baseline, demographic, anthropometric, disease-related characteristics and endothelial function parameters were similar between the exercise and control groups (p>0.05). Repeated measures analysis of variance revealed a significant improvement in endothelial function parameters at 3 (GTN: p<0.001) or 6 months (Ach: p=0.016, SNP: p=0.045, FMD: p=0.016) in the exercise but not in the control group. Generalised estimated equations detected that maximal oxygen uptake was a strong predictor for the observed changes in Ach (p=0.009) and GTN (p<0.001) whereas logCRP for SNP (p=0.017) and GTN (p=0.008). Conclusions An exercise programme designed to meet individual needs and physical abilities significantly improves microvascular and macrovascular function in parallel with disease-related characteristics in RA patients. The potential long-term beneficial effects of such interventions at reducing cardiovascular risk in these patients merit further exploration. Clinical Trial Registration ISRCTN50861407.

Polymorphisms of the Endothelin-1 Gene Associate with Hypertension in Patients with Rheumatoid Arthritis

Rheumatoid arthritis (RA) associates with excess cardiovascular (CV) morbidity and mortality. Hypertension, a highly prevalent entity in RA, has been associated with the endothelin-1 (ET-1) gene locus (EDN1) in some groups, such as Afro-Caribbean, the obese, and in low-renin states, but not in the general population as a whole. High levels of plasma ET-1 have been observed in RA. This study evaluated the potential association of EDN1 gene locus and serum ET-1 levels with hypertension in patients with RA. Genomic DNA and serum samples were collected from 397 well-characterized RA patients; DNA was also available from 401 local general population controls without RA. To explore the overall relevance of EDN1, two suitable single-nucleotide polymorphisms (SNPs), rs1800541 and rs5370, were selected and haplotype analysis was performed. Both SNPs were identified using real-time polymerase chain reaction (PCR) and melting curve analysis. Genetic analysis was related to hypertension as dichotomous trait and to blood pressure indices as continuous variables. Serum endothelin levels were also assessed in the RA patients. No genotype or haplotype differences were observed between RA and control subjects. Within RA, logistic regression analysis of each SNP separately revealed a threefold increase in the adjusted odds of being hypertensive of rs5370 TT homozygotes compared to GG homozygotes (OR = 2.89, 95%CI: 1.02 to 8.19). After adjustment for multiple potential confounders, haplotype analysis revealed an additive effect of the rs1800541-rs5370 T-T haplotype on hypertension (OR = 2.96, 95%CI: 1.28 to 6.86; p = .011), systolic blood pressure (SBP) (beta = 6.75 +/- 2.57 mm Hg; p = .009), and pulse pressure (PP) (beta = 4.37 +/- 2.12 mm Hg; p = .040). There was an increased prevalence of raised ET-1 levels amongst hypertensive RA patients, whereas a similar trend was observed for T-T haplotype carriers. RA patients who carry the rs1800541-rs5370 T-T EDN1 haplotype appear more likely to be hypertensive with an increased SBP and PP. These findings, if replicated in future studies, could be used as a screening tool for RA patients at increased hypertension, and thus cardiovascular, risk.

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

IntroductionInsulin 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.MethodsPatients 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.ResultsFollowing 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.ConclusionsAnti-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.

Target organ damage in patients with rheumatoid arthritis: The role of blood pressure and heart rate

BACKGROUND Rheumatoid arthritis (RA) is characterised by increased cardiovascular morbidity and mortality. Even though hypertension (HT) is highly prevalent in RA, the extent of target organ damage (TOD) caused by it remains unknown. Inflammation and sympathetic overdrive may also associate with TOD. We investigated the prevalence and associations of TOD in RA. METHODS In this cross-sectional, observational study, 251 RA patients with no overt cardiovascular or renal disease had extensive clinical and laboratory evaluations, including a 12-lead electrocardiogram and urine albumin:creatinine ratio. Pulse pressure (PP) was used as a proxy of arterial stiffness and heart rate (HR) of autonomic activity. TOD was defined as described in the European guidelines for the management of arterial hypertension. Binary logistic regression analysis was used to evaluate the independence of the variables that associated with the presence of TOD. RESULTS TOD prevalence was 23.5% (59/251). Of the 59 patients with TOD, 45.8% had suboptimally controlled HT, whereas 32.3% had undiagnosed HT. In univariable analysis, TOD was significantly associated with higher age (64.2+/-11.7 years vs. 58.0+/-12.4 years, p=0.001), HT prevalence (89.8% vs. 60.4%, p<0.001), systolic blood pressure (SBP) (150.3+/-18.8mmHg vs. 139.7+/-20.7mmHg, p=0.001), PP (70.6+/-16.6mmHg vs. 60.3+/-17.3mmHg, p<0.001), HR (77.1+/-15.4bpm vs. 72.2+/-12.2bpm, p<0.001), serum uric acid (320.6+/-88.8mumol/l vs. 285.0+/-74.9mumol/l, p=0.03) and type 2 diabetes mellitus prevalence (13.6% vs. 4.7%, p=0.019). Binary logistic regression analysis revealed that only hypertension indices and HR associated independently with TOD. CONCLUSIONS TOD is highly prevalent in patients with RA and associates independently with hypertension, arterial stiffness and heart rate. Further prospective studies are needed to confirm these findings and examine the role of beta-blockers in this particular population.

Predictors of asymmetric dimethylarginine levels in patients with rheumatoid arthritis: the role of insulin resistance.

Objective: To determine whether demographic, inflammatory, and metabolic factors predict elevated asymmetric dimethylarginine (ADMA) levels in rheumatoid arthritis (RA). Method: A total of 67 RA patients [mean age 56 ± 12 years, median disease duration 8 (3–15) years] were assessed. Routine biochemistry tests, lipid profile, glycaemic profile [glucose, insulin, homeostasis model assessment (HOMA), quantitative insulin sensitivity check index (QUICKI)], and inflammatory markers were measured in all patients. ADMA levels were measured by enzyme-linked immunosorbent assay (ELISA). Regression analyses were performed to identify predictors of ADMA in RA. Results: Regression analysis revealed that HOMA (β = 0.149, p = 0.003) was an independent predictor of ADMA in RA. From the drug factors, anti-hypertensive medication use was associated with lower ADMA levels (β = −0.081, p = 0.004). ADMA was not associated with RA disease-related parameters or any of the other cardiovascular risk factors that were assessed. Conclusions: HOMA, a strong indicator of insulin resistance, seems to be the main predictor of elevated ADMA levels in RA patients; ADMA may reflect an important pathway linking abnormal insulin metabolism with endothelial dysfunction in RA.

Lack of an Association of GNB3 C825T Polymorphism and Blood Pressure in Patients with Rheumatoid Arthritis

G-protein beta 3 subunit (GNB3) C825T (rs5443) single nucleotide polymorphism (SNP) has been implicated as a risk factor for essential hypertension in the general population. The effects of this SNP may be more prominent in subjects with endothelial dysfunction (ED). Rheumatoid arthritis (RA) is associated with ED and has a high prevalence of hypertension. Thus far, this SNP has not been studied in RA patients. We genotyped 383 RA patients and 432 controls. GNB3 C825T was identified using real-time polymerase chain reaction (PCR) and melting curve analysis. There were no differences in the frequencies of the GNB3 C825T genotype and alleles between RA and controls. Within RA patients, prevalence of hypertension did not differ across genotypes. The TT versus CC+CT contrast yielded an adjusted odds ratio (OR) of 0.92 (95% CI: 0.49 to 1.76, p = 0.813), the contrast of TT+CT versus CC an adjusted OR of 2.17 (95% CI: 0.885 to 5.30, p = 0.091), whereas that of the T allele versus C allele an adjusted OR of 1.11 (95% CI: 0.76 to 1.61, p = 0.604). Systolic and diastolic blood pressure levels were not significantly different across the three genotypic groups. No significant interaction was observed between GNB3 825C/T polymorphism and serum endothelin levels. Data from the present study suggest that the T825 variant of the G protein β3 subunit gene is unlikely to constitute major susceptibility loci for essential hypertension in Caucasian RA patients. Further larger studies are required to confirm our findings and assess the interaction of rs5443 with environmental factors.