Risk factor profiles for atherosclerotic cardiovascular disease in black and other Africans with established rheumatoid arthritis

Hypertension in connective tissue disease

It is well documented that connective tissue disease (CTD) is a type of autoimmune disease characterized by chronic inflammation, which can occur across various organ systems throughout the whole body. Although the clinical manifestations of CTD are different, studies have shown that different CTD diseases have similar pathogenesis, implying that different CTD diseases may have similar clinical outcomes. Recent population-based studies have demonstrated an increased risk of cardiovascular disease (CVD) in patients with CTD compared with the control group, which is partially attributed to traditional cardiovascular risk factors, such as hypertension (HT), and that controlling the patients' blood pressure (BP) still constitutes one of the most effective means to prevent CVD. Although many studies have shown that the prevalence of HT in patients with CTD is higher than that in the general population, there is a lack of adequate data on the possible pathogenesis of HT. Also, the factors that promote the rise of BP, especially the relationship between connective tissue disease- hypertension (CTD-HT) and traditional cardiovascular risk factors (aging, sex, race, dyslipidemia, diabetes mellitus, smoking, obesity, etc.), have not been fully confirmed. In this review, we explore the mechanisms that might lead to elevated BP in patients with CTD and the factors that contribute to elevated BP and the management of CTD-HT, and we focus on whether traditional cardiovascular risk factors, the disease, and the presence of related therapeutic drugs are associated with an increased risk of HT in patients with CTD.

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

Introduction

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

Methods

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

Results

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

Conclusions

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

Points to consider in cardiovascular disease risk management among patients with rheumatoid arthritis living in South Africa, an unequal middle income country

BACKGROUND

It is plausible that optimal cardiovascular disease (CVD) risk management differs in patients with rheumatoid arthritis (RA) from low or middle income compared to high income populations. This study aimed at producing evidence-based points to consider for CVD prevention in South African RA patients.

METHODS

Five rheumatologists, one cardiologist and one epidemiologist with experience in CVD risk management in RA patients, as well as two patient representatives, two health professionals and one radiologist, one rheumatology fellow and 11 rheumatologists that treat RA patients regularly contributed. Systematic literature searches were performed and the level of evidence was determined according to standard guidelines.

RESULTS

Eighteen points to consider were formulated. These were grouped into 6 categories that comprised overall CVD risk assessment and management (n = 4), and specific interventions aimed at reducing CVD risk including RA control with disease modifying anti-rheumatic drugs, glucocorticoids and non-steroidal anti-inflammatory drugs (n = 3), lipid lowering agents (n = 8), antihypertensive drugs (n = 1), low dose aspirin (n = 1) and lifestyle modification (n = 1). Each point to consider differs partially or completely from recommendations previously reported for CVD risk management in RA patients from high income populations. Currently recommended CVD risk calculators do not reliably identify South African black RA patients with very high-risk atherosclerosis as represented by carotid artery plaque presence on ultrasound.

CONCLUSIONS

Our findings indicate that optimal cardiovascular risk management likely differs substantially in RA patients from low or middle income compared to high income populations. There is an urgent need for future multicentre longitudinal studies on CVD risk in black African patients with RA.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The Prevalence of Atherosclerosis in Those with Inflammatory Connective Tissue Disease by Race, Age, and Traditional Risk Factors

Systemic inflammation promotes cardiovascular disease. Inflammatory connective tissue diseases (CTD) like lupus and rheumatoid arthritis associate with cardiovascular risk, but it is unknown whether particular groups of patients have enhanced propensity for atherosclerotic cardiovascular disease (ASCVD) associated with their CTD. Analysis of aggregate health record data at a large U.S. academic center identified CTD and ASCVD status for 287,467 African American and white adults. ASCVD prevalence in those with CTD was 29.7% for African Americans and 14.7% for white patients with prevalence ratios, compared to those without CTD, of 3.1 and 1.8, respectively. When different types of CTD were analyzed individually (rheumatoid arthritis; lupus; scleroderma; Sjögren Syndrome; dermatomyositis/polymyositis; unspecified/mixed CTD; other inflammatory arthropathy), increased ASCVD rates were found in nearly all subsets, always with higher prevalence ratios in African Americans. The prevalence ratio of ASCVD was particularly high in young African Americans. Furthermore, individuals lacking traditional cardiovascular risk factors had more ASCVD if they had CTD (prevalence ratio 2.9). Multivariate analysis confirmed a positive interaction between CTD and African-American race and a negative interaction between CTD and age. The factors driving the observed disproportionate CTD-associated ASCVD in African Americans, young adults, and those without traditional risk factors warrant further study.

The Framingham Score and the Systematic Coronary Risk Evaluation at Low Cutoff Values Are Useful Surrogate Markers of High-risk Subclinical Atherosclerosis in Patients with Rheumatoid Arthritis

Objective.

We determined the performance of the Framingham score and the Systematic COronary Risk Evaluation (SCORE) in assessing high-risk atherosclerosis in patients with rheumatoid arthritis (RA).

Methods.

We assembled 330 cases without established cardiovascular disease (CVD), diabetes, and moderate or severe chronic kidney disease among 451 consecutive Spanish patients who underwent CVD risk screening and carotid ultrasound-determined plaque assessment. The findings were validated in 90 black and 97 white African patients.

Results.

When sensitivity for the Framingham score was set at 80% in receiver-operator curve analysis [area under the curve (AUC) = 0.799], the corresponding cutoff value and specificity were 7.3% and 63%, respectively. At a specificity of 80%, the cutoff value and sensitivity were 10.8% and 65%, respectively. When sensitivity for SCORE (AUC = 0.747) was set at 80%, the cutoff value and specificity were 0.5% and 58%, respectively. At a specificity of 80%, the cutoff value and sensitivity were 1.5% and 50%, respectively. Upon applying a cutoff value of 7.3% for the Framingham and 0.5% for SCORE in African white patients with RA, the corresponding sensitivities and specificities were 67% and 72%, and 67% and 55%, respectively. CVD risk equations did not discriminate between black African patients with and without plaque (AUC = 0.544 and 0.549 for Framingham score and SCORE, respectively).

Conclusion.

The Framingham score and SCORE at markedly low cutoff values of 7.3% to 10.8% and 0.5% to 1.5%, respectively, can usefully estimate plaque presence in RA. Effective population-specific CVD risk assessment strategies are needed in black African patients with RA.

Cardiovascular disease risk amongst African black patients with rheumatoid arthritis: the need for population specific stratification

Rheumatoid arthritis (RA) enhances the risk of cardiovascular disease to a similar extent as diabetes. Whereas atherogenesis remains poorly elucidated in RA, traditional and nontraditional risk factors associate similarly and additively with CVD in RA. Current recommendations on CVD risk stratification reportedly have important limitations. Further, reported data on CVD and its risk factors derive mostly from data obtained in the developed world. An earlier epidemiological health transition is intrinsic to persons living in rural areas and those undergoing urbanization. It is therefore conceivable that optimal CVD risk stratification differs amongst patients with RA from developing populations compared to those from developed populations. Herein, we briefly describe current CVD and its risk factor profiles in the African black population at large. Against this background, we review reported data on CVD risk and its potential stratification amongst African black compared to white patients with RA. Routinely assessed traditional and nontraditional CVD risk factors were consistently and independently related to atherosclerosis in African white but not black patients with RA. Circulating concentrations of novel CVD risk biomarkers including interleukin-6 and interleukin-5 adipokines were mostly similarly associated with both endothelial activation and atherosclerosis amongst African black and white RA patients.

Marked independent relationship between circulating interleukin-6 concentrations and endothelial activation in rheumatoid arthritis

We examined the potential impact of conventional compared with nonconventional cardiovascular risk factors including interleukin-6 levels on endothelial activation in RA. Circulating soluble E-selectin, vascular cell adhesion molecule-1, intercellular adhesion molecule-1, and monocyte chemoattractant protein-1 concentrations were measured in 217 African patients (112 black and 105 white) with RA. In comprehensive confounder adjusted mixed regression models, 5 conventional and 4 nonconventional cardiovascular risk factors were associated (P = 0.05 to <0.0001) with endothelial activation. Interleukin-6 was the only risk factor related to each endothelial activation molecule and independently contributed by 18% and significantly more than other risk factors to the variation in overall endothelial activation as estimated by an SD (z) score of endothelial activation molecule concentrations. The independent interleukin-6-overall endothelial activation relationships were reproduced in various subgroups. Interleukin-6 concentrations relate consistently, markedly, and to a larger extent than other cardiovascular risk factors to endothelial activation in RA. Assessment of interleukin-6 concentrations may enhance cardiovascular risk stratification in RA.

Independent associations of total and high molecular weight adiponectin with cardiometabolic risk and surrogate markers of enhanced early atherogenesis in black and white patients with rheumatoid arthritis: a cross-sectional study

INTRODUCTION

Whether adiponectin levels associate with atherogenesis in RA is uncertain. We examined the independent relationships of total and high molecular weight (HMW) adiponectin concentrations with cardiometabolic risk and surrogate markers of enhanced early atherogenesis in black and white patients with RA.

METHODS

We determined total and HMW adiponectin concentrations and those of endothelial activation molecules including soluble E-selectin, vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1) and monocyte chemoattractant protein-1 (MCP-1), in 210 (119 black and 91 white) RA patients. Associations were determined in potential confounder and mediator adjusted mixed regression models.

RESULTS

Total and HMW adiponectin concentrations related similarly to metabolic risk factors and endothelial activation. In all patients, total and HMW adiponectin concentrations associated paradoxically with high systolic, diastolic and mean blood pressure (partial R = 0.155 to 0.241, P ≤ 0.03). Ethnic origin did not impact on these relationships (interaction P ≥ 0.09). Total and HMW adiponectin concentrations associated with those of glucose in white and black patients respectively (partial R = -0.304, P = 0.006 and -0.246, P = 0.01). In black but not white participants, total and HMW adiponectin concentrations also related favorably to lipid profiles (partial R = 0.292 to 0.360, P ≤ 0.003 for HDL cholesterol concentrations, -0.269 to -0.299, P ≤ 0.006 for triglyceride concentrations and -0.302 to -0.390, P ≤ 0.002 for total-HDL cholesterol ratio) and the number of metabolic risk factors (partial R = -0.210 to -0.238, P ≤ 0.03). In white but not black patients, total and HMW adiponectin concentrations associated paradoxically with overall endothelial activation as estimated by a standard z-score of endothelial activation molecule concentrations (partial R = 0.262, P = 0.01 and 0.252, P = 0.02); in the respective models, the extent of effect of total and HMW adiponectin concentrations on endothelial activation was larger in white compared to black participants (standardized β (SE) = 0.260 (0.107) versus -0.106 (0.107), P = 0.01 and 0.260 (0.120) versus -0.100 (0.111), P = 0.02). The HMW-total adiponectin ratio related inconsistently to metabolic risk factors and not to endothelial activation.

CONCLUSION

In this study, total and HMW adiponectin concentrations associated with increased blood pressure parameters, and in white patients additionally with endothelial activation. The potential mechanism(s) underlying these paradoxical relationships between adiponectin concentrations and cardiovascular risk in RA merit further investigation.

Rheumatoid arthritis is associated with reduced adiposity but not with unfavorable major cardiovascular risk factor profiles and enhanced carotid atherosclerosis in black Africans from a developing population: a cross-sectional study

Introduction

Rheumatoid arthritis (RA) is characterized by inflamed joint-derived cytokine-mediated high-grade systemic inflammation that enhances cardiovascular metabolic risk and disease in developed populations. We investigated the potential impact of RA on cardiovascular risk factors including systemic inflammation and atherosclerosis, and their relationships in black Africans from a developing population.

Methods

We evaluated demographic features, adiposity indices, major traditional cardiovascular risk factors, circulating C-reactive protein and interleukin-6 concentrations and ultrasound determined carotid intima-media thickness (cIMT) in 274 black Africans; 115 had established RA. Data were analyzed in confounder-adjusted mixed regression models.

Results

The body mass index and waist-height ratio were lower in RA compared to non-RA subjects (29.2 (6.6) versus 33.7 (8.0), P < 0.0001 and 0.58 (0.09) versus 0.62 (0.1), P = 0.0003, respectively). Dyslipidemia was less prevalent in patients with RA (odds ratio (OR) (95% confidence interval (CI) = 0.54 (0.30 to1.00)); this disparity was no longer significant after further adjustment for reduced adiposity and chloroquine use. RA was also not associated with hypertension, current smoking and diabetes. The number of major traditional risk factors did not differ by RA status (1.1 (0.8) versus 1.2 (0.9), P = 0.7). Circulating C-reactive protein concentrations were similar and serum interleukin-6 concentrations reduced in RA (7.2 (3.1) versus 6.7 (3.1) mg/l, P = 0.7 and 3.9 (1.9) versus 6.3 (1.9) pg/ml, P < 0.0001, respectively). The cIMT was 0.700 (0.085) and 0.701 (0.111) mm in RA and non-RA subjects, respectively (P = 0.7). RA disease activity and severity parameters were consistently unrelated to systemic inflammation, despite the presence of clinically active disease in 82.6% of patients. In all participants, adiposity indices, smoking and converting angiotensin inhibitor non-use were associated with increased systemic inflammation, which related to more atherogenic lipid profiles, and circulating low density lipoprotein concentrations were associated with cIMT (partial R = 0.153, P = 0.032); RA did not impact on these relationships (interaction P ≥0.1).

Conclusions

Among black Africans, patients with established RA experience reduced overall and abdominal adiposity but no enhanced major traditional risk factor and atherosclerosis burden. This study further suggests that an absent interleukin-6 release by inflamed RA joints into the circulation may account for this unaltered cardiovascular disease risk.

Metabolic syndrome in rheumatoid arthritis: case control study

Background

Metabolic syndrome, a cluster of classical cardiovascular risk factors, including hypertension, obesity, glucose intolerance, and dyslipidemia is highly prevalent in patients with rheumatoid arthritis (RA). The aim of the study was to assess the frequency of metabolic syndrome (MS) in RA patients, and to evaluate the relationships between metabolic syndrome and RA.

Methods

The study was conducted on 120 RA patients according to the 1987 revised American College of Rheumatology classification criteria, and 100 age and sex matched apparently healthy controls. The frequency of metabolic syndrome was assessed using six Metabolic Syndrome definitions (Joint Consensus 2009, National Cholesterol Education Programme 2004 and 2001, International Diabetes Federation, World Health Organisation and European Group for Study of Insulin Resistance). Logistic regression was used to identify independent predictors of metabolic Syndrome.

Results

The frequency of metabolic syndrome varied from 18 to 48.6% in RA according to the definition used and was significantly higher than controls (for all definitions p<0.05). In multivariate analysis, higher ESR was independently associated with the presence of Met S (OR =1.36; CI: 1.18–2.12; p = 0.03). Glucocorticoid use, but not other disease modifying anti-rheumatic drugs (DMARDs), values remained significant independent predictors of the presence of metabolic syndrome in RA patients (OR = 1.45; CI: 1.12–2.14; p = 0.04).

Conclusions

In summary, the frequency of metabolic syndrome in RA varies according to the definition used and was significantly higher compared to controls (for all definitions p<0.05). Higher systemic inflammatory marker, and glucocorticoids use were independent predictors associated with the presence of metabolic syndrome in patients with RA. These findings suggest that physicians should screen for metabolic syndrome in patients with RA to control its components and therefore reduce the risk of cardiovascular disease in these patients.

Rheumatoid arthritis impacts on the independent relationships between circulating adiponectin concentrations and cardiovascular metabolic risk

Adiponectin and leptin are likely involved in the pathophysiology of rheumatoid arthritis (RA) and therefore potential new therapeutic targets. Adiponectin inhibition could be expected to enhance cardiovascular metabolic risk. However, it is unknown whether RA changes the influence of adipokines on cardiovascular metabolic risk. We determined whether RA impacts on the independent relationships of circulating leptin and adiponectin concentrations with cardiovascular risk factors and carotid intima-media thickness (cIMT) in 277 black African subjects from a developing population; 119 had RA. RA impacted on the relationships of adiponectin concentrations with lipid concentrations and blood pressure, independent of confounders including adiposity (interaction P < 0.05). This translated into an association of adiponectin concentrations with more favorable lipid variables including HDL cholesterol (P = 0.0005), non-HDL cholesterol (P = 0.007), and triglyceride (P = 0.005) concentrations, total cholesterol-HDL cholesterol (P = 0.0002) and triglycerides-HDL cholesterol (P = 0.0003) ratios, and higher systolic (P = 0.0006), diastolic (P = 0.0004), and mean blood pressure (P = 0.0007) in RA but not non-RA subjects. Leptin was not associated with metabolic risk after adjustment for adiposity. The cIMT did not differ by RA status, and adipokine concentrations were unrelated to atherosclerosis. This study suggests that leptin and adiponectin inhibition may not alter overall cardiovascular risk and disease in RA.

The carotid artery atherosclerosis burden and its relation to cardiovascular risk factors in black and white Africans with established rheumatoid arthritis: a cross-sectional study

OBJECTIVE

Black Africans currently experience a distinctly low frequency of atherosclerotic cardiovascular disease. Whether this protection persists in those with rheumatoid arthritis (RA) is unknown. We compared the carotid atherosclerosis burden and its relationships with cardiovascular (CV) risk factors between Africans with RA from a developing black and developed CV population.

METHODS

We performed high resolution B-mode ultrasonography and assessed CV risk factors in 243 patients with established RA, of whom 121 were black and 122 white. Data were analyzed in age, sex, and healthcare center-adjusted regression models.

RESULTS

The mean±SD common carotid intima-media thickness (cIMT) was 0.694±0.097 mm in black and 0.712±0.136 mm in white patients (adjusted p=0.8). Plaque prevalence was also similar in black compared to white cases (35.5% and 44.3%, respectively; adjusted OR 0.83, 95% CI 0.32-2.20, p=0.7). Interactions between population grouping and several CV risk factors were independently associated with cIMT and plaque. In stratified analysis, that is, in each population group separately, risk factors associated with cIMT or/and plaque comprised the systolic blood pressure (p=0.02), serum cholesterol/high-density lipoprotein cholesterol ratio (p=0.004), C-reactive protein concentrations (p=0.01), and the presence of extraarticular manifestations (p=0.01) in whites but, contrastingly, the Arthritis Impact Measurement Scales tension score (p=0.04) and use of nonsteroidal antiinflammatory agent (p=0.03) in black patients. The Framingham score was significantly associated with atherosclerosis only in whites (p<0.0001).

CONCLUSION

The carotid atherosclerosis burden is similar in black compared to white Africans with RA, but relationships between modifiable CV risk factors and atherosclerosis vary substantially among Africans with RA.

Obesity and carotid atherosclerosis in African black and Caucasian women with established rheumatoid arthritis: a cross-sectional study

INTRODUCTION

Reported findings on the relationship between adiposity and atherosclerotic cardiovascular disease (ACVD) risk in rheumatoid arthritis (RA) are contradictory and originate in developed populations. Approximately 80% of ACVD now occurs in developing countries. We aimed to ascertain the associations of clinical obesity measures with metabolic cardiovascular risk and atherosclerosis in African women with RA from a developing black and developed Caucasian population.

METHODS

The associations of body mass index (BMI) as an indicator of overall adiposity and waist circumference and waist-to-height and waist-to-hip ratios as abdominal obesity indices with metabolic risk factors and high resolution B-mode ultrasound-determined carotid artery atherosclerosis were assessed in multivariate regression models in 203 African women with established RA; 108 were black and 95 Caucasian.

RESULTS

BMI and waist-to-height ratio were higher in African black compared to Caucasian women (29.9 (6.6) versus 25.3 (4.9) kg/m2, P = 0.002 and 0.59 (0.09) versus 0.53 (0.08), P = 0.01, respectively). Interactions between population origin and anthropometric measures were not related to metabolic risk factors but were associated with atherosclerosis, independent of confounders and individual terms. In all patients, BMI was related to systolic and diastolic blood pressure but not with serum lipid concentrations whereas abdominal obesity indices were associated with serum lipid concentrations but not with blood pressure values; obesity measures that were associated with plasma glucose concentrations comprised BMI, waist circumference and waist-to-height ratio (P < 0.05 in multiple confounder adjusted analysis). In African Caucasian women, BMI was associated with common carotid artery intima-media thickness (standardized β (95% confidence interval (CI)) = 0.21 (0.03 to 0.38)) and waist-to-hip ratio with plaque (odds ratio (OR) (95% CI) = 1.83 (1.03 to 3.25) for one standard deviation (SD) increase). These relationships were independent of multiple non-metabolic risk factors and explained by metabolic risk factors. In African black women with RA, none of the obesity measures was related to atherosclerosis.

CONCLUSIONS

Obesity in women with RA from developing groups of black African descent does not as yet translate into atheroma. In Caucasian women with RA that belong to developed populations, BMI and waist-to-hip ratio should be considered in ACVD risk assessment.