Arterial stiffness in relation to subclinical atherosclerosis

Differences in carotid to femoral pulse wave velocity and carotid intima media thickness between vegetarian and omnivorous diets in healthy subjects: a systematic review and meta-analysis

Background: Arterial stiffness and atherosclerosis are known risk factors for cardiovascular morbidity and mortality. Vegetarian diets have been associated with cardiovascular benefits, including improvements in metabolic parameters. However, the impact of a vegetarian diet on cardiovascular parameters, specifically arterial stiffness and atherosclerosis, in healthy individuals remains unclear. Thus, this study aims to analyze differences in arterial stiffness and atherosclerosis between vegetarian and omnivorous diets in healthy subjects. Methods: A systematic review and meta-analysis were conducted following established guidelines. PubMed, Scopus, Web of Science, and Cochrane Library databases were searched for studies examining the association between vegetarian and omnivorous diets with arterial stiffness and atherosclerosis. Cross-sectional studies reporting carotid to femoral pulse wave velocity (cf-PWv) as a measure of arterial stiffness and carotid intima media thickness (c-IMT) as a measure of atherosclerosis were included. Data were synthesized using random effects models, and sensitivity analyses, meta-regressions, and assessment of publication bias were performed. Results: Ten studies were included in the systematic review, and seven studies were included in the meta-analysis. The pooled analysis demonstrated that individuals following a vegetarian diet had differences in the levels of arterial stiffness (cf-PWv) compared to those following an omnivorous diet (MD: -0.43 m s-1; 95% CI: -0.63, -0.23). Similarly, atherosclerosis (c-IMT) was found to be different in individuals adhering to a vegetarian dietary pattern (MD = -29.86 mm; 95% CI: -58.41, -1.32). Conclusions: Our findings suggest that a vegetarian diet is associated with improved arterial stiffness and reduced atherosclerosis in healthy individuals. These results support the inclusion of a well-balanced vegetarian dietary pattern in the prevention and management of cardiovascular diseases. However, further research is needed to explore the effects of a vegetarian diet on arterial health in diverse populations and to assess long-term cardiovascular outcomes.

Triglyceride glucose index for the prediction of subclinical atherosclerosis and arterial stiffness: A meta-analysis of 37,780 individuals

Insulin resistance (IR), which can be assessed by triglyceride-glucose (TyG) index, is a major contributor to the pathogenesis of cardiovascular diseases. Arterial stiffness is an index of subclinical atherosclerosis. We conducted this systematic review and meta-analysis to summarize the existing studies and provide a quantitative assessment of the significance of the TyG index in predicting the incidence of subclinical atherosclerosis and arterial stiffness. A comprehensive literature search in PubMed, EMBASE, and Web of Science databases from inception until 30 April 2022 was conducted. Published observational studies that evaluated the association between TyG index and arterial stiffness among the adult population and reported odds ratio (OR) for this association after multivariate analysis were included. The random-effects model was used for the estimation of pooled ORs with the corresponding confidence intervals (CIs). A total of 9 observational studies, including 37780 participants, were included. Seven out of the 9 studies analyzed the TyG index as a categorical variable and showed a statistically significant association between TyG index and incident arterial stiffness (pooled OR 1.96, 95% CI 1.52-2.53, P<0.00001, I²=82%). Additionally, similar results were in the three studies that analyzed TyG index as a continuous variable (pooled OR 1.37, 95% CI 1.26-1.49, P<0.00001, I²=0%). In conclusion, our meta-analysis demonstrates that a higher TyG index is associated with higher odds of subclinical atherosclerosis and arterial stiffness. TyG index may be used as an independent predictor of an increased risk of subclinical atherosclerosis and arterial stiffness.

Association between Alcohol Intake and Arterial Stiffness in Healthy Adults: A Systematic Review

Background: Arterial stiffness as assessed by Pulse Wave Velocity (PWV) represents an independent predictor of cardiovascular disease. Several dietary compounds and lifestyle factors could influence arterial stiffness. The debate on the significance of the correlation between alcohol consumption and arterial stiffness is still open, given that the relationship is complex and potentially affected by several factors such as alcohol type, consumption levels, gender and age differences. Objective: This systematic literature review aims to examine the evidence supporting an association between alcohol use and PWV, in electronic databases including PubMed/MEDLINE and the Cochrane Library, from January 2010 to November 2020. Screening and full-text reviews were performed by three investigators and data extraction by two. Considering the significant heterogeneity of data only a qualitative analysis (systematic review) was performed. Results: A total of 13 studies met the inclusion criteria. Alcohol consumption was independently associated with arterial stiffness in a J-shaped way in most of the studies included. A benefit of alcohol consumption on arterial stiffness was found in four experimental studies, whilst an unfavorable increasing linear association was found in four others. Associations were confirmed with both oscillometric and tonometric PWV assessment methods. In some studies, a gender and age correlation was found with a more pronounced association in older males. In all studies elevated levels of alcohol consumption were associated with a worsening of arterial stiffness. Conclusions: Despite the variable findings across studies, the current review provides preliminary evidence that light-to-moderate alcohol consumption is associated with arterial stiffness values lower than expected, and evidence that high doses accelerate arterial ageing. These findings could be useful for clinicians who provide recommendations for patients at cardiovascular (CV) risk. Nevertheless, given the heterogeneity of study designs, interventions, measurement methods and statistical evaluations, the protective role of moderate alcohol consumption on arterial stiffness is likely but not certain, warranting additional trials and evidence.

The relationship between bioelectrical impedance parameters and pulmonary artery stiffness in obese subjects

OBJECTIVES

Obesity is a public health problem that needs to be treated and it occurs as a result of excessive fat accumulation in the body. The relationship between obesity and pulmonary hypertension is well known. The aim of this study is to evaluate the relationship between pulmonary artery stiffness, right ventricular functions and bioelectrical impedance parameters in obese, overweight, and healthy individuals.

METHODS

In this study, 41 obese (17 female and 24 male, mean age 43.5±10.3), 39 overweight (20 female and 19 male, mean age 38.6±10.4), 34 healthy control group (19 female and 15 male, mean age 40.5±8.6) were included. Anthropometric measurements and bioelectrical impedance parameters of all participants were performed. Right ventricular functions and pulmonary artery stiffness were evaluated by using conventional echocardiography.

RESULTS

Right ventricle myocardial performance index, pulmonary artery stiffness values were statistically different between groups. Positive correlation was observed between pulmonary artery stiffness and Body Mass Index, Waist and Hip circumferences. Significant negative correlation was observed between muscle to fat ratio and pulmonary artery stiffness. In the linear regression analysis, it was observed that the muscle to fat ratio was independent predictor of pulmonary artery stiffness (β = -1.835; 95%CI(-2.434 - - .784); p < 0.001).

CONCLUSIONS

This study showed that right ventricular function was impaired and pulmonary artery stiffness increased in obese individuals. These findings could be considered as early markers of pulmonary hypertension in obese patients who do not yet have clinical evidence of cardiovascular disease.

Detection of Early Vascular Atherosclerosis in Type 2 Diabetes Mellitus Using Ultrasound Radiofrequency-Data Technique

OBJECTIVES

To quantitatively evaluate changes in vascular elasticity and intima-media thickness (IMT) of the common carotid artery (CCA) with Ultrasound radiofrequency (RF)-data technology in asymptomatic patients with type-2 diabetes mellitus (T2DM) and controls.

MATERIALS AND METHODS

Thirty-seven T2DM patients and 39 controls were enrolled. Arterial elasticity and CCA-IMT were quantitatively assessed by RF-data technology. The CCA diameters in the diastolic and systolic phases, carotid distensibility (CD), IMT, values of stiffness (β) and local pulse wave velocity (PWVβ) were measured and compared between the two groups.

RESULTS

The T2DM group had significantly larger CCA diastolic and systolic diameter, lower CD values, higher IMT measurements (all p < 0.001), and higher values of β and PWVβ (all P < 0.05) than the controls. Significant differences were not revealed in the mean values of IMT, β, PWVβ and CD across both sides of the CCA (all P > 0.05).

CONCLUSIONS

Higher IMT measurement and lower arterial elasticity of the CCA are significantly pronounced in asymptomatic T2DM patients and may suggest atherosclerotic changes, and the ultrasound RF-data technique may be used as a potential approach for detection of early-stage atherosclerosis.

Stimulation of vascular smooth muscle cell proliferation by stiff matrix via the IKCa channel-dependent Ca2+ signaling

Vascular stiffening, an early and common characteristic of cardiovascular diseases (CVDs), stimulates vascular smooth muscle cell (VSMC) proliferation which reciprocally accelerates the progression of CVDs. However, the mechanisms by which extracellular matrix stiffness accompanying vascular stiffening regulates VSMC proliferation remain largely unknown. In the present study, we examined the role of the intermediate-conductance Ca²⁺ -activated K⁺  (IK_Ca ) channel in the matrix stiffness regulation of VSMC proliferation by growing A7r5 cells on soft and stiff polydimethylsiloxane substrates with stiffness close to these of arteries under physiological and pathological conditions, respectively. Stiff substrates stimulated cell proliferation and upregulated the expression of the IK_Ca channel. Stiff substrate-induced cell proliferation was suppressed by pharmacological inhibition using TRAM34, an IK_Ca channel blocker, or genetic depletion of the IK_Ca channel. In addition, stiff substrate-induced cell proliferation was also suppressed by reducing extracellular Ca²⁺ concentration using EGTA or intracellular Ca²⁺ concentration using BAPTA-AM. Moreover, stiff substrate induced activation of extracellular signal-regulated kinases (ERKs), which was inhibited by treatment with TRAM34 or BAPTA-AM. Stiff substrate-induced cell proliferation was suppressed by treatment with PD98059, an ERK inhibitor. Taken together, these results show that substrates with pathologically relevant stiffness upregulate the IK_Ca channel expression to enhance intracellular Ca²⁺ signaling and subsequent activation of the ERK signal pathway to drive cell proliferation. These findings provide a novel mechanism by which vascular stiffening regulates VSMC function.

Non-invasive evaluation of the common carotid artery in normal adults using ultrasound radiofrequency data technology

AIM

To evaluate the changes in CCA-IMT and vascular elasticity in healthy subjects in relation to age using radiofrequency data technology, to produce reference values for potential clinical applications.

MATERIALS AND METHODS

The following variables were measured in 160 subjects using radiofrequency data techniques: CCA-IMT, carotid distensibility (CD), local pulse-wave velocity (PWVβ), and stiffness (β). The subjects were divided into four age groups (30-39, 40-49, 50-59, and 60-69 years), with 20 men and 20 women in each group. The above parameters were compared among the different age groups.

RESULTS

CCA-IMT increased significantly with age (p<0.05). CD decreased significantly in the 40-49-years compared with the 30-39-years age group (p<0.05). PWVβ showed a significant increase in the 30-39-, 40-49-, and 50-59-years age groups (p<0.05). β increased significantly in the 50-59- compared with the 40-49-years age group (p<0.05). Compared with the 50-59-years age group, CD, PWVβ, and β showed no significant changes in the 60-69-years age group (p>0.05), with mean values of 329.39 ± 102.06 μm, 7.22 ± 1.91 m/s, and 10.04 ± 4.91, respectively.

CONCLUSION

Ultrasound radiofrequency data technology provides a non-invasive method for quantitatively and accurately assessing increased CCA-IMT and reduced vascular elasticity in healthy subjects in different age groups. The reference values produced in this study will be useful in clinical practice.

Increased bioavailability of phenolic acids and enhanced vascular function following intake of feruloyl esterase-processed high fibre bread: A randomized, controlled, single blind, crossover human intervention trial

BACKGROUND & AIMS

Clinical trial data have indicated an association between wholegrain consumption and a reduction in surrogate markers of cardiovascular disease. Phenolics present in wholegrain bound to arabinoxylan fibre may contribute these effects, particularly when released enzymatically from the fiber prior to ingestion. The aim of the present study was therefore to determine whether the intake of high fibre bread containing higher free ferulic acid (FA) levels (enzymatically released during processing) enhances human endothelium-dependent vascular function.

METHODS

A randomized, single masked, controlled, crossover, human intervention study was conducted on 19 healthy men. Individuals consumed either a high fibre flatbread with enzymatically released free FA (14.22 mg), an equivalent standard high fibre bread (2.34 mg), or a white bread control (0.48 mg) and markers of vascular function and plasma phenolic acid concentrations were measured at baseline, 2, 5 and 7 h post consumption.

RESULTS

Significantly increased brachial arterial dilation was observed following consumption of the high free FA ('enzyme-treated') high fibre bread verses both a white bread (2 h: p < 0.05; 5 h: p < 0.01) and a standard high fibre bread (5 h: p < 0.05). Concurrently, significant increases in plasma FA levels were observed, at 2 h (p < 0.01) after consumption of the enzyme-treated bread, relative to control treatments. Blood pressure, heart rate, DVP-SI and DVP-RI were not significantly altered following intake of any of the breads (p > 0.05).

CONCLUSION

Dietary intake of bread, processed enzymatically to release FA from arabinoxylan fiber during production increases the bioavailability of FA, and induces acute endothelium-dependent vasodilation.

CLINICAL TRIAL REGISTRY

NO: NCT03946293. WEBSITE: www.clinicaltrials.gov.

Live endothelial cells on plasma-nitrided and oxidized titanium: An approach for evaluating biocompatibility

We evaluated the effects of titanium plasma nitriding and oxidation on live endothelial cell viscoelasticity. For this, mechanically polished titanium surfaces and two surfaces treated by planar cathode discharge in nitriding (36N₂ and 24H₂) and oxidant (36O₂ and 24H₂). Surfaces were characterized regarding wettability, roughness and chemical composition. Rabbit aortic endothelial cells (RAECs) were cultured on the titanium surfaces. Cell morphology, viability and viscoelasticity were evaluated by scanning electron microscopy (SEM), methyl thiazolyl tetrazolium (MTT) assay and atomic force microscopy (AFM), respectively. Grazing Incidence X-ray Diffraction confirmed the presence of TiN_0,26 on the surface (grazing angle theta 1°) of the nitrided samples, decreasing with depth. On the oxidized surface had the formation of TiO₃ on the material surface (Theta 1°) and in the deeper layers was noted, with a marked presence of Ti (Theta 3°). Both plasma treatments increased surface roughness and they are hydrophilic (angle <90°). However, oxidation led to a more hydrophilic titanium surface (66.59° ± 3.65 vs. 76.88° ± 2.68; p = 0.001) due to titanium oxide films in their stoichiometric varieties (Ti₃O, TiO₂, Ti₆O), especially Ti₃O. Despite focal adhesion on the surfaces, viability was different after 24 h, as cell viability on the oxidized surface was higher than on the nitrided surface (9.1 × 10³ vs. 4.5 × 10³cells; p < 0.05). This can be explained by analyzing the viscoelastic property of the cellular cytoskeleton (nuclear and peripheral) by AFM. Surface oxidation significantly increased RAECs viscoelasticity at cell periphery, in comparison to the nucleus (2.36 ± 0.3 vs. 1.5 ± 0.4; p < 0.05), and to the RAECs periphery in contact with nitrided surfaces (1.36 ± 0.7; p < 0.05) and polished surfaces (1.55 ± 0.6; p < 0.05). Taken together, our results have shown that titanium plasma treatment directly increased cell viscoelasticity via surface oxidation, and this mechanobiological property subsequently increased biocompatibility.

Association of Adipocytokines With Carotid Intima Media Thickness and Arterial Stiffness in Obstructive Sleep Apnea Patients

Objective: Obstructive sleep apnea (OSA) results in increased carotid intima-media thickness (IMT) and arterial stiffness; however, the association between adipocytokines and IMT/arterial stiffness in OSA patients is unclear. Methods: We enrolled 95 normal weight and overweight, not obese, participants from May 2018 to December 2018 in this study. All subjects underwent a carotid artery ultrasound examination and polysomnography. Blood samples were used to determine serum chemerin, adiponectin, SFRP5, and apelin levels. Correlations between two quantitative variables were assessed using the Pearson or Spearman coefficient. Stepwise models of multiple linear regression analysis were performed to assess the independent relationships. Result: IMT in OSA patients was significantly higher than in the non-snorers. There were significant differences in the arterial stiffness parameters such as distensibility coefficient (DC), compliance coefficient (CC), and pulse wave velocity (PWV). SFRP5 level was lower in OSA patients than in non-snorers. Adiponectin correlated with CC, DC, and PWV among OSA patients; however, the relationship disappeared after a multivariable adjustment. Age was independently associated with all quantitative IMT and stiffness indices. AHI and minimum oxygen saturation (Mini SaO₂) were independently related to arterial stiffness. Conclusion: The quantitative IMT and carotid arterial elasticity were significantly worse among OSA patients. Age was the main independent factor correlated with quantitative IMT and arterial stiffness, and AHI and mini SaO₂ were associated factors. There were no relationships between aforementioned adipocytokines and quantitative IMT/carotid arterial stiffness.

Evaluation of Subclinical Atherosclerosis by Ultrasound Radiofrequency Data Technology in Patients With Familial Mediterranean Fever

OBJECTIVES

The aim of this study was to noninvasively demonstrate the presence of early risk associated with subclinical inflammatory activity in patients with familial Mediterranean fever (FMF) who had stable disease, using ultrasound (US) radiofrequency data technology.

METHODS

A total of 110 participants, including 55 patients with FMF and 55 healthy control participants, were evaluated with Doppler US. The intima-media thickness and arterial stiffness were measured from bilateral common carotid arteries (CCAs) by the radiofrequency method.

RESULTS

No statistically significant difference was found between the patients with FMF and controls in terms of the right and left CCA intima-media thickness, distensibility coefficient, compliance coefficient, α and β stiffness indices, and pulsed wave velocity (P > .05). Symptom duration and diagnosis and treatment time of the patients with FMF had a negative correlation with the distensibility and compliance measurements obtained by Doppler US (r = -0.324 and -0.303), and a positive (r = 0.380 and 0.339) and statistically significant relationship was detected between the α stiffness index, β stiffness index, and pulsed wave velocity (P < .05).

CONCLUSIONS

Common carotid artery intima-media thickness and arterial stiffness measurements can aid in early prediction of cardiovascular disease development in patients with FMF. Radiofrequency data technology provides a noninvasive method for accurately and quantitatively showing the CCA intima-media thickness elevation and the decrease in vascular elasticity in patients with FMF.

Association between skeletal muscle mass to visceral fat area ratio and arterial stiffness in Chinese patients with type 2 diabetes mellitus

BACKGROUND

The skeletal muscle mass-to-visceral fat area ratio (SVR) has been linked to arterial stiffness in non-diabetic adults. We examined the association between the SVR and arterial stiffness in patients with type 2 diabetes mellitus (T2DM).

METHODS

Patients with type 2 diabetes mellitus (252 men and 171 women) aged 40-75 years were enrolled and divided into three groups according to SVR tertiles. Arterial stiffness was measured as brachial-ankle pulse wave velocity (baPWV), with baPWV> 1800 mm/s defined as high. Spearman's partial correlation was used to adjust confounding factors. The odds ratio for high baPWV was determined by multiple logistic regression analyses, and receiver-operating characteristic analysis was conducted.

RESULTS

SVR was associated with baPWV in Chinese patients with T2DM (Spearman's partial correlation = - 0.129, P < 0.01). SVR was found to be significantly associated with baPWV on multiple logistic regression analysis. Patients in the lower SVR tertiles had a higher OR than did those in the higher SVR tertiles, after adjusting for multiple covariates (Q1: OR = 4.33 in men and 4.66 in women; Q3: OR = 1). The area under the curve for SVR was significantly greater than that for appendicular skeletal muscle (ASM), ASM/height², and visceral fat area (VAF) for identifying high baPWV (0.747 in men and 0.710 in women). The optimal cutoffs values of SVR for detecting high baPWV were 191.7 g/cm² for men and 157.3 g/cm² for women.

CONCLUSIONS

SVR has an independent, negative association with arterial stiffness, and is a better risk-assessment tool than ASM, ASM/height², and VFA in clinical practice to identify patients with type 2 diabetes at high cardiovascular risk.

A combination of experimental and numerical methods to investigate the role of strain rate on the mechanical properties and collagen fiber orientations of the healthy and atherosclerotic human coronary arteries

Atherosclerosis enables to alter not only the microstructural but also the physical properties of the arterial walls by plaque forming. Few studies so far have been conducted to calculate the isotropic or anisotropic mechanical properties of the healthy and atherosclerotic human coronary arteries. To date there is a paucity of knowledge on the mechanical response of the arteries under different strain rates. Therefore, the objective of the concurrent research was to comprehend whether the alteration in the strain rates of the human atherosclerotic arteries in comparison with the healthy ones contribute to the biomechanical behaviors. To do this, healthy and atherosclerotic human coronary arteries were removed from 18 individuals during autopsy. Histological analyses by both an expert histopathologist and an imaged-based recognizer software were performed to figure out the average angle of collagen fibers in the healthy and atherosclerotic arterial walls. Thereafter, the samples were subjected to 3 diverse strain rates, i.e., 5, 20, and 50 mm/min, until the material failure occurs. The stress-strain diagrams of the arterial tissues were calculated in order to capture their linear elastic and nonlinear hyperelastic mechanical properties. In addition, Artificial Neural Networks (ANNs) was employed to predict the alteration of mean angle of collagen fibers during load bearing up to failure. The findings suggest that strain rate has a significant (p < 0.05) role in the linear elastic and nonlinear hyperelastic mechanical properties as well as the mean angle of collagen fibers of the atherosclerotic arteries, whereas no specific impact on the healthy ones. Furthermore, the mean angle of collagen fibers during the load bearing up to the failure at each strain rate was well predicted by the proposed ANNs code.

Extracellular Matrix Disarray as a Mechanism for Greater Abdominal Versus Thoracic Aortic Stiffness With Aging in Primates

OBJECTIVE

Increased vascular stiffness is central to the pathophysiology of aging, hypertension, diabetes mellitus, and atherosclerosis. However, relatively few studies have examined vascular stiffness in both the thoracic and the abdominal aorta with aging, despite major differences in anatomy, embryological origin, and relation to aortic aneurysm.

APPROACH AND RESULTS

The 2 other unique features of this study were (1) to study young (9±1 years) and old (26±1 years) male monkeys and (2) to study direct and continuous measurements of aortic pressure and thoracic and abdominal aortic diameters in conscious monkeys. As expected, aortic stiffness, β, was increased P<0.05, 2- to 3-fold, in old versus young thoracic aorta and augmented further with superimposition of acute hypertension with phenylephrine. Surprisingly, stiffness was not greater in old thoracic aorta than in young abdominal aorta. These results can be explained, in part, by the collagen/elastin ratio, but more importantly, by disarray of collagen and elastin, which correlated best with vascular stiffness. However, vascular smooth muscle cell stiffness was not different in thoracic versus abdominal aorta in either young or old monkeys.

CONCLUSIONS

Thus, aortic stiffness increases with aging as expected, but the most severe increases in aortic stiffness observed in the abdominal aorta is novel, where values in young monkeys equaled, or even exceeded, values of thoracic aortic stiffness in old monkeys. These results can be explained by alterations in collagen/elastin ratio, but even more importantly by collagen and elastin disarray.

Extracellular Matrix Stiffness Controls VEGF Signaling and Processing in Endothelial Cells

Vascular endothelial growth factor A (VEGF) drives endothelial cell maintenance and angiogenesis. Endothelial cell behavior is altered by the stiffness of the substrate the cells are attached to suggesting that VEGF activity might be influenced by the mechanical cellular environment. We hypothesized that extracellular matrix (ECM) stiffness modifies VEGF-cell-matrix tethering leading to altered VEGF processing and signaling. We analyzed VEGF binding, internalization, and signaling as a function of substrate stiffness in endothelial cells cultured on fibronectin (Fn) linked polyacrylamide gels. Cell produced extracellular matrices on the softest substrates were least capable of binding VEGF, but the cells exhibited enhanced VEGF internalization and signaling compared to cells on all other substrates. Inhibiting VEGF-matrix binding with sucrose octasulfate decreased cell-internalization of VEGF and, inversely, heparin pre-treatment to enhance Fn-matrix binding of VEGF increased cell-internalization of VEGF regardless of matrix stiffness. β1 integrins, which connect cells to Fn, modulated VEGF uptake in a stiffness dependent fashion. Cells on hard surfaces showed decreased levels of activated β1 and inhibition of β1 integrin resulted in a greater proportional decrease in VEGF internalization than in cells on softer matrices. Extracellular matrix binding is necessary for VEGF internalization. Stiffness modifies the coordinated actions of VEGF-matrix binding and β1 integrin binding/activation, which together are critical for VEGF internalization. This study provides insight into how the microenvironment may influence tissue regeneration and response to injury and disease. J. Cell. Physiol. 231: 2026-2039, 2016. © 2016 Wiley Periodicals, Inc.

Circulating adhesion molecules and arterial stiffness

Aim

VCAM-1 and ICAM-1 are two important members of the immunoglobulin gene superfamily of adhesion molecules, and their potential role as biomarkers of diagnosis, severity and prognosis of cardiovascular disease has been investigated in a number of clinical studies. The aim of the present study was to determine the relationship between circulating ICAM-1 and VCAM-1 levels and aortic stiffness in patients referred for echocardiographic examination.

Methods

Aortic distensibility was determined by echocardiography using systolic and diastolic aortic diameters in 63 consecutive patients referred for echocardiography. Venous samples were collected in the morning after a 12-hour overnight fast, and serum concentrations of ICAM-1 and VCAM-1 were measured using commercial enzyme immunoassay kits.

Results

Data of a total of 63 participants (mean age 55.6 ± 10.5 years, 31 male) were included in the study. Circulating levels of adhesion molecules were VCAM-1: 12.604 ± 3.904 ng/ml and ICAM-1: 45.417 ± 31.429 ng/ml. We were unable to demonstrate any correlation between indices of aortic stiffness and VCAM-1 and ICAM-1 levels.

Conclusion

The role of soluble adhesion molecules in cardiovascular disease has not been fully established and clinical studies show inconsistent results. Our results indicate that levels of circulating adhesion molecules cannot be used as markers of aortic stiffness in patients.

Secoiridoids delivered as olive leaf extract induce acute improvements in human vascular function and reduction of an inflammatory cytokine: a randomised, double-blind, placebo-controlled, cross-over trial

The leaves of the olive plant (Olea europaea) are rich in polyphenols, of which oleuropein and hydroxytyrosol (HT) are most characteristic. Such polyphenols have been demonstrated to favourably modify a variety of cardiovascular risk factors. The aim of the present intervention was to investigate the influence of olive leaf extract (OLE) on vascular function and inflammation in a postprandial setting and to link physiological outcomes with absorbed phenolics. A randomised, double-blind, placebo-controlled, cross-over, acute intervention trial was conducted with eighteen healthy volunteers (nine male, nine female), who consumed either OLE (51 mg oleuropein; 10 mg HT), or a matched control (separated by a 4-week wash out) on a single occasion. Vascular function was measured by digital volume pulse (DVP), while blood collected at baseline, 1, 3 and 6 h was cultured for 24 h in the presence of lipopolysaccharide in order to investigate effects on cytokine production. Urine was analysed for phenolic metabolites by HPLC. DVP-stiffness index and ex vivo IL-8 production were significantly reduced (P< 0.05) after consumption of OLE compared to the control. These effects were accompanied by the excretion of several phenolic metabolites, namely HT and oleuropein derivatives, which peaked in urine after 8-24 h. The present study provides the first evidence that OLE positively modulates vascular function and IL-8 production in vivo, adding to growing evidence that olive phenolics could be beneficial for health.

The Relationship Between High Pulse Pressure and Low Ankle-Brachial Index. Potential Utility in Screening for Peripheral Artery Disease in Population-Based Studies

INTRODUCTION

The ankle-brachial index (ABI) is a reliable screening procedure for peripheral artery disease detection. However, ABI testing is time-consuming and requires trained personnel, which may preclude its routine use in population-based surveys. Preliminary data suggest a relationship between ABI values and pulse pressure (PP) levels.

AIM

To assess whether PP calculation might help to detect persons who need ABI screening in population-based studies.

METHODS

All Atahualpa residents aged ≥60 years were identified during a door-to-door survey and invited to undergo ABI testing. Non-consented persons and those with ABI ≥1.4 were excluded. Using generalized linear and logistic regression models adjusted for demographics and cardiovascular risk factors, as well as receiver operator characteristics curve analysis, we evaluated the association between PP values and ABI, as well as the reliability of PP to identify candidates for ABI testing.

RESULTS

Out of 239 participants (mean age 70 ± 8 years, 62 % women), 46 (19 %) had an ABI ≤0.9 and 136 (57 %) had PP >65 mmHg, with a negative relationship between them (R = -0.386, p < 0.0001). A PP >65 mmHg was associated with an ABI ≤ 0.9 in the logistic regression model (OR 3.46, 95 % CI 1.07-11.2, p = 0.038). Continuous PP levels also correlated negatively with ABI (β -0.0014, 95 % CI -0.0024 to -0.0004, p = 0.005). The sensitivity of a PP >65 mmHg to predict a low ABI was 85 %, and the specificity was 50 %. In contrast, the sensitivity of blood pressure ≥140/90 mmHg was 27 % and the specificity was 10 %. The area under the curve for the predictive value of a PP >65 mmHg was 0.673 (95 % CI 0.609-0.736), and that of a blood pressure ≥140/90 mmHg was 0.371 (95 % CI 0.30-0.443), with a significant difference between them (p < 0.0001).

CONCLUSIONS

PP calculation may be a simple tool to detect candidates for ABI testing in population-based studies.

A combination of low-dose fluvastatin and valsartan decreases inflammation and oxidative stress in apparently healthy middle-aged males

PURPOSE

We have previously shown that a "short-term, low-dose" treatment approach with statins, angiotensin receptor blockers, and especially their low-dose combination, is effective in improving arterial wall properties in apparently healthy middle-age men. This study was performed to expand investigation of its effects on inflammation and oxidative stress.

METHODS

The study was performed supplementary to 3 previous studies, overall 65 treated participants (25 received fluvastatin 10 mg, 20 valsartan 20 mg, 20 their combination) and 65 participants placebo. The stored blood samples (collected at inclusion and after 30 days of treatment) were used to measure high-sensitivity CRP, interleukin-6, vascular cell adhesion molecule-1, total antioxidant status, glutathione peroxidase, and selenium concentration.

RESULTS

A low-dose combination decreased inflammation parameters (high-sensitivity CRP: from 1.2 ± 0.1 to 0.7 ± 0.1 mg/L; P < .001; vascular cell adhesion molecule-1: from 523 ± 21 to 482 ± 12 pg/mL; P < .05; while interleukin-6 did not reach the level of significance). It also increased antioxidant defenses, as measured by total antioxidant status and glutathione peroxidase (from 1.4 ± 0.04 to 1.5 ± 0.04 mmol/L; P < .01, and from 1.2 ± 0.06 to 1.4 ± 0.06 μkat/g hemoglobin; P < .05, respectively), accompanied by decreased selenium levels. Low-dose valsartan was separately less effective than the combination. No changes were observed in the control groups.

CONCLUSIONS

Low-dose combination of fluvastatin and valsartan and, to a lesser extent low-dose valsartan alone, produced important anti-inflammatory and anti-oxidative effects. These results confirm and extend the potential of the "short-term, low-dose" preventive strategy.

Genetic determinants of arterial stiffness

Stiffness of large arteries (called arteriosclerosis) is an independent predictor of cardiovascular morbidity and mortality. Although previous studies have shown that arterial stiffness is moderately heritable, genetic factors contributing to arterial stiffness are largely unknown. In this paper, we reviewed the available literature on genetic variants that are potentially related to arterial stiffness. Most variants have shown mixed depictions of their association with arterial stiffness across multiple studies. Various methods to measure arterial stiffness at different arterial sites can contribute to these inconsistent results. In addition, studies in patient populations with hypertension or atherosclerosis may overestimate the impact of genetic variants on arterial stiffness. Future studies are recommended to standardize current measures of arterial stiffness in different age groups. Studies conducted in normal healthy subjects may also provide better opportunities to find novel genetic variants of arterial stiffness.

The low-dose atorvastatin and valsartan combination effectively protects the arterial wall from atherogenic diet-induced impairment in the guinea pig

New preventive strategies for atherosclerosis are needed. In this study, we tested whether a new therapeutic approach consisting of low-dose treatment with a statin and sartan combination could prevent atherogenic diet-induced impairment of the arterial wall in guinea pigs. Twenty-five Dunkin-Hartley guinea pigs were randomly assigned to five experimental groups: 1) normal diet; 2) atherogenic diet (AD); 3) AD + a low-dose atorvastatin and valsartan combination (5mg/kg/day and 2.4mg/kg/day, respectively); 4) AD + low-dose atorvastatin (5mg/kg/day); 5) AD + low-dose valsartan (2.4mg/kg/day). After 8 weeks of treatment, the animals were killed, blood samples collected and thoracic and abdominal aortas isolated. The atherogenic diet significantly impaired maximal thoracic aorta endothelium-dependent relaxation by 40.1% relative to the normal diet. The low-dose combination, compared to the separate drugs, completely preserved thoracic aorta endothelium-dependent relaxation at the level of the group receiving normal diet. This substantial effect was associated with a significant change in the expression of NOS3 (R=0.93; P=0.0002) and IL1b (R=-0.79; P=0.003) genes. In addition, treatment with the low-dose combination or the separate drugs also prevented atherosclerotic plaque formation. We found that treatment with the low-dose atorvastatin and valsartan combination has the capability to completely protect the arterial wall from atherogenic diet-induced damage in the guinea pig model. Further studies evaluating this new therapeutic approach are desirable.

Arterial stiffness, the brain and cognition: a systematic review

BACKGROUND

Arterial stiffness is a known predictor of cardiovascular disease, and has also been associated with markers of cerebral small vessel disease as well as poor cognitive function and cognitive decline. The consistency of these associations and their relationship to each other are unclear.

METHOD

We conducted a systematic review of the evidence associating arterial stiffness with cognitive function and cognitive decline, and with makers of cerebral small vessel disease, specifically lacunar infarcts and white matter hyperintensities.

RESULTS

Thirteen cross-sectional studies examining arterial stiffness and white matter hyperintensities or lacunar infarctions reported a positive association between increased arterial stiffness and radiological findings of cerebral small vessel disease. Two longitudinal studies examining the relationship between arterial stiffness and white matter hyperintensities found increased pulse wave velocity to be an independent predictor of white matter hyperintensity volume. Fifteen cross-sectional and seven longitudinal studies examining arterial stiffness and cognition were identified. Fourteen of the fifteen cross-sectional studies associated increased arterial stiffness with lower cognitive function, and six of the seven longitudinal studies found arterial stiffness to be predictive of cognitive decline.

CONCLUSION

Arterial stiffness is associated with cerebral small vessel disease and decreased cognitive function. However methodological limitations such as differing covariates between studies and an over-reliance on the MMSE to measure cognition are a concern across much of the literature.

Changes in biomechanical properties of the coronary artery wall contribute to maintained contractile responses to endothelin-1 in atherosclerosis

AIMS

Our aim was to determine whether alterations in biomechanical properties of human diseased compared to normal coronary artery contribute to changes in artery responsiveness to endothelin-1 in atherosclerosis.

MAIN METHODS

Concentration-response curves were constructed to endothelin-1 in normal and diseased coronary artery. The passive mechanical properties of arteries were determined using tensile ring tests from which finite element models of passive mechanical properties of both groups were created. Finite element modelling of artery endothelin-1 responses was then performed.

KEY FINDINGS

Maximum responses to endothelin-1 were significantly attenuated in diseased (27±3 mN, n=55) compared to normal (38±2 mN, n=68) artery, although this remained over 70% of control. There was no difference in potency (pD2 control=8.03±0.06; pD2 diseased=7.98±0.06). Finite element modelling of tensile ring tests resulted in hyperelastic shear modulus μ=2004±410 Pa and hardening exponent α=22.8±2.2 for normal wall and μ=2464±1075 Pa and α=38.3±6.7 for plaque tissue and distensibility of diseased vessels was decreased. Finite element modelling of active properties of both groups resulted in higher muscle contractile strain (represented by thermal reactivity) of the atherosclerotic artery model than the normal artery model. The models suggest that a change in muscle response to endothelin-1 occurs in atherosclerotic artery to increase its distensibility towards that seen in normal artery.

SIGNIFICANCE

Our data suggest that an adaptation occurs in medial smooth muscle of atherosclerotic coronary artery to maintain distensibility of the vessel wall in the presence of endothelin-1. This may contribute to the vasospastic effect of locally increased endothelin-1 production that is reported in this condition.

Abdominal obesity and low-grade systemic inflammation as markers of subclinical organ damage in type 2 diabetes

AIM

This study aimed to explore the associations between abdominal obesity, inflammatory markers and subclinical organ damage in 740 middle-aged patients with type 2 diabetes.

METHODS

Waist circumference (WC) and sagittal abdominal diameter (SAD) were measured, and blood samples were analyzed for C-reactive protein (CRP) and IL-6. Carotid intima-media thickness (IMT) was evaluated by ultrasonography, and aortic pulse wave velocity (PWV) measured with applanation tonometry.

RESULTS

Abdominal obesity as determined by SAD and WC was significantly correlated with IL-6 (WC: r=0.27, P<0.001; SAD: r=031, P<0.001), CRP (WC: r=0.29, P<0.001; SAD: r=0.29, P<0.001), IMT (WC: r=0.09, P=0.013; SAD: r=0.11, P=0.003) and PWV (WC: r=0.18, P<0.001; SAD: r=0.21, P<0.001). In multiple linear regressions with IMT and PWV as dependent variables, and age, gender, statin use, systolic blood pressure (SBP), body mass index (BMI), CRP and HbA1c as independent variables, both SAD and WC remained associated with IMT and PWV. On stepwise linear regression and entering both SAD and WC, the association between SAD and PWV was stronger than the association between WC and PWV.

CONCLUSION

Both SAD and WC are feasible measures of obesity, and both provide information on inflammation, atherosclerosis and arterial stiffness in type 2 diabetes, while SAD appears to be slightly more robustly associated with subclinical organ damage than WC.

Toe brachial index in middle aged patients with diabetes mellitus type 2: not just a peripheral issue

AIM

To explore risk factors for peripheral arterial disease (PAD) as well as the association between toe blood pressure and subclinical and clinical central vascular disease in patients with type 2 diabetes.

METHOD

Toe brachial index (TBI) was cross-sectionally analyzed in 742 middle-aged (54-66 years) patients with type 2 diabetes as well as non-diabetic controls and related to other vascular measures (e.g. carotid intima media thickness (IMT), presence of carotid plaque, central arterial stiffness and left ventricular mass index) and previous cardiovascular events.

RESULTS

A TBI ≤ 0.7 was seen in 22% of the patients but only one patient had severe TBI reduction (TBI ≤ 0.3). The corresponding figures in the controls were 13% and 0%, respectively. Mean TBI was significantly lower in patients with type 2 diabetes than in controls (0.81 ± 0.14 vs. 0.87 ± 0.15, p<0.001). In patients with diabetes, a lower TBI was associated with increased central arterial stiffness (p<0.001), IMT (p<0.001) and carotid plaque (p<0.001) as well as with decreasing glomerular filtration rate (p<0.001). Lower TBI was found in patients with previous macrovascular ischemic events. Furthermore, TBI was negatively correlated with age (p<0.001), diabetes duration (p<0.001) and HbA1c (p=0.01).

CONCLUSION

PAD, assessed with TBI, is common in a Swedish middle-aged diabetes type 2 cohort, affecting about one-fifth. As ankle pressure may be confounded by falsely high values in patients with diabetes due to media calcification we conclude that information about TBI may improve the risk evaluation regarding arteriosclerotic disease in both small and large vessels in type 2 diabetes.

Sagittal abdominal diameter is a more independent measure compared with waist circumference to predict arterial stiffness in subjects with type 2 diabetes--a prospective observational cohort study

Background

Anthropometric measurements are useful in clinical practice since they are non-invasive and cheap. Previous studies suggest that sagittal abdominal diameter (SAD) may be a better measure of visceral fat depots. The aim of this study was to prospectively explore and compare how laboratory and anthropometric risk markers predicted subclinical organ damage in 255 patients, with type 2 diabetes, after four years.

Methods

Baseline investigations were performed in 2006 and were repeated at follow-up in 2010. Carotid intima-media thickness (IMT) was evaluated by ultrasonography and aortic pulse wave velocity (PWV) was measured with applanation tonometry over the carotid and femoral arteries at baseline and at follow-up in a cohort of subjects with type 2 diabetes aged 55–65 years old.

Results

There were significant correlations between apolipoprotein B (apoB) (r = 0.144, p = 0.03), C - reactive protein (CRP) (r = 0.172, p = 0.009) at baseline and IMT measured at follow-up. After adjustment for sex, age, treatment with statins and Hba1c, the associations remained statistically significant. HbA1c, total cholesterol or LDL-cholesterol did not correlate to IMT at follow-up. Baseline body mass index (BMI) (r = 0.130, p = 0.049), waist circumference (WC) (r = 0.147, p = 0.027) and sagittal Abdominal Diameter (SAD) (r = 0.184, p = 0.007) correlated to PWV at follow-up. Challenged with sex, SBP and HbA1c, the association between SAD, not WC nor BMI, and PWV remained statistically significant (p = 0.036). In a stepwise linear regression, entering both SAD and WC, the association between SAD and PWV was stronger than the association between WC and PWV.

Conclusions

We conclude that apoB and CRP, but not LDL-cholesterol predicted subclinical atherosclerosis. Furthermore, SAD was more independent in predicting arterial stiffness over time, compared with WC, in middle-aged men and women with type 2 diabetes.

Blood volume pulse (BVP) derived vagal tone (VT) between 5 and 7 years of age: a methodological investigation of measurement and longitudinal stability

The present study evaluated the possibility of collecting cardiac vagal tone data using a photoplethysmograph, and its stability and continuity in a longitudinal sample of early-school aged children. A method for the optical (i.e., blood volume pulse) estimation of heart rate was established in a pilot study. Then the longitudinal stability and continuity in photoplethysmograph-derived vagal tone was assessed in 114 children (56 girls) at three sessions between 5 and 7 years of age. Results indicate that this method possesses substantial measurement reliability and individual stability, as children report low intra-individual variation over time. Children also report a mean decrease in vagal tone from 5 to 7 years of age, consistent with increased attentional capacity. Overall, this suggests blood volume pulse estimation of vagal tone is both accurate and appropriate for naturalistic developmental research.

Prevalence of low ankle brachial index and its association with pulse pressure in an elderly Chinese population: a cross-sectional study

Background

We investigated the prevalence of low ankle brachial index (ABI) and the association of low ABI with pulse pressure among elderly community residents in China.

Methods

This population-based cross-sectional study was conducted in Beijing and recruited 2982 participants who were aged 60 years or older in 2007. Low ABI was defined as an ABI value less than 0.9 in either leg. Participants with or without stroke or coronary heart disease (CHD) were analyzed separately. The association between pulse pressure and low ABI was examined by using multiple logistic regression models.

Results

The prevalence of low ABI was 5.65% (4.24% among men and 6.52% among women; P = 0.0221) among participants without stroke or CHD and 10.91% (13.07% among men and 9.49% among women; P = 0.1328) among those with stroke or CHD. After adjusting for confounders, the odds ratio (95% CI) for each 5-mm Hg increase in pulse pressure was 1.19 (1.07, 1.33) and 1.10 (1.02, 1.20) for men and women, respectively, among participants without stroke or CHD and 1.17 (1.03, 1.34) and 1.15 (1.02, 1.30) for men and women with stroke or CHD. When pulse pressure was classified into quartiles and the lowest quartile was used as reference, the association between pulse pressure and low ABI remained positive in men and women.

Conclusions

Low ABI was prevalent among elderly Chinese, and pulse pressure was positively associated with low ABI.

Carotid intima-media thickness and arterial stiffness in type 1 diabetic patients with and without microangiopathy

INTRODUCTION

The aim of the study was to assess carotid intima-media thickness (CIMT) as a subclinical marker of atherosclerosis and arterial stiffness in type 1 diabetic patients in relation to microangiopathy.

MATERIAL AND METHODS

We included 87 type 1 diabetic patients (44 women, 43 men), median age 34 years (interquartile range [IQR] 29-43), median disease duration 10 years (IQR: 9-14), mean ± standard deviation (SD) glycated haemoglobin (HbA(1c)) 8.4 ±1.4%. Fifty patients had at least one microangiopathic complication. Intima-media thickness (IMT) of the common carotid artery was measured using high resolution ultrasonography. Arterial stiffness was assessed using digital volume pulse analysis and tonometric measurement of wave reflection and central haemodynamics.

RESULTS

SUBJECTS WITH MICROANGIOPATHY COMPARED WITH THOSE WITHOUT HAD HIGHER VALUES OF CIMT (MEDIAN [IQR]: 0.53 mm [0.45-0.60 mm] vs 0.47 mm [0.34-0.52 mm], p = 0.002), higher central augmentation index (CAI(x)) (mean ± SD: 120.2 ±19.4% vs. 110.5 ±17.1%, p = 0.016) and higher peripheral augmentation index (PAI(x)) (65.7 ±18.1% vs. 57.2 ±14.9%, p = 0.023). In the logistic regression analysis, the duration of diabetes, systolic and diastolic blood pressure, postprandial glycaemia, HbA(1c) and triglycerides predicted the presence of diabetic microangiopathy independently of age and sex. The CIMT, CAI(x) and PAI(x) were associated with the presence of diabetic microangiopathy only in the univariate model.

CONCLUSIONS

In type 1 diabetic patients with microangiopathic complications, increased carotid IMT and arterial stiffness were observed. The study confirms the role of traditional risk factors for late diabetic complications, such as the duration of the disease and metabolic control in the development of microangiopathy.

Quantitative evaluation of the structure and function of the common carotid artery in hypertriglyceridemic subjects using ultrasound radiofrequency-data technology

Assessment of the properties of blood-vessel walls by ultrasound radiofrequency (RF)-data technology is an innovative technique. We quantitatively evaluated the intima-media thickness (IMT) and arterial elasticity of the common carotid artery (CCA) in asymptomatic subjects with hypertriglyceridemia (HTG) using RF-data technology. Thirty HTG subjects and 30 matched controls were enrolled in the study. The common carotid arterial systolic diameter, diastolic diameter, IMT, carotid distensibility (CD), local pulse wave velocity (PWVβ), and stiffness (β) were compared between the two groups, as was the correlation between triglyceride level and the parameters mentioned above. The HTG group had significantly higher values of CCA-IMT compared with the control group (p<0.001). There were significant differences between the HTG group and controls in terms of higher values of PWVβ and β, and lower values of CD (all p<0.05). No difference was observed in terms of the systolic and diastolic diameter of the CCA (p>0.05). The level of triglycerides had significant positive correlations with CCA-IMT (r=0.493, p<0.001), whereas significant correlations with CD, PWVβ, and β were not observed in the HTG group. Ultrasound RF-data technology can be used to non-invasively and quantitatively detect the change in the structure and function of the CCA in asymptomatic HTG subjects for evaluating preclinical atherosclerosis.

The effects of low-dose fluvastatin and valsartan combination on arterial function: a randomized clinical trial

BACKGROUND

Ageing progressively diminishes arterial functions, even in the absence of traditional risk factors. Our aim was to explore whether age-related arterial changes in middle-aged males could be reversed using short-term, low-dose fluvastatin/valsartan combination intervention.

METHODS

Forty apparently healthy, middle-aged males (43.3 ± 5.8 years) were recruited in a double-blind, randomised intervention. Individuals received either 10mg fluvastatin/20mg valsartan daily or placebo over 30 days. The brachial artery flow mediated dilation (FMD), pulse wave velocity (PWV) and common carotid artery β-stiffness were assessed at baseline and after 30 days, and again 5-10 months after therapy discontinuation.

RESULTS

Arterial function variables significantly improved after 30 days of intervention; FMD improved by 167.7% (P<0.001), PWV by 10.9% (P<0.05) and β-stiffness by 18.8% (P<0.01), whereas no changes were obtained in the placebo group. The favourable outcomes in the intervention group were accompanied by a significant decrease of high sensitivity-C reactive protein levels (1.8-fold; P<0.05). In contrast, lipids and blood pressure remained unchanged. Surprisingly, the beneficial arterial effects were still present to a substantial degree 7 months after completing intervention (remaining % of initial improvement: FMD 82.1%, PWV 69.5% and β-stiffness 68.5%), but declined substantially after 10 months.

CONCLUSION

Our results indicate that age-related arterial changes, at least in middle-aged males, can be reversed. Short-term treatment with a low-dose fluvastatin/valsartan combination resulted in a large and long lasting improvement of arterial function.

Abdominal obesity vs general obesity for identifying arterial stiffness, subclinical atherosclerosis and wave reflection in healthy, diabetics and hypertensive

Background

Our aim was to analyze the relationship between abdominal obesity and general obesity, with subclinical atherosclerosis, arterial stiffness and wave reflection in healthy, diabetics and hypertensive subjects.

Methods

A cross-sectional descriptive study was made of 305 individuals (diabetics 32.8%, hypertensive subjects 37.0% and healthy individuals 30.2%). Measurements: Body mass index (BMI), waist circumference (WC), body fat percentage (BFP) and waist/height ratio (WHtR). Arterial stiffness was assessed according to pulse wave velocity (PWV), intima-media thickness of the common carotid artery (C-IMT), augmentation index (central and peripheral), ankle-brachial index (ABI), and central and peripheral pulse pressure.

Results

WC and WHtR showed a positive correlation to PWV and C-IMT in the studied groups. After adjusting for age, gender, high sensitivity c-reactive protein, serum glucose and the presence of diabetes, hypertension, smoking, dyslipidemia, antidiabetic drugs, lipid-lowering drugs, and atherosclerotic plaques, it was seen that for every 0.1 point increase in WHtR, and for every cm increase in WC, the PWV increased 0.041 and 0.029 m/sec, and C-IMT increased 0.001 mm and 0.001 mm, respectively.

Conclusions

The measures of abdominal obesity (WHtR and WC) correlates better than BMI and BFP with arterial stiffness evaluated by PWV, and with subclinical atherosclerosis evaluated by C-IMT, independently of the presence of diabetes or hypertension.

Trial Registration

Clinical Trials.gov Identifier: NCT01325064

DHA-rich fish oil reverses the detrimental effects of saturated fatty acids on postprandial vascular reactivity

BACKGROUND

Experimental elevation of nonesterified fatty acids (NEFAs) impairs endothelial function, but the effect of NEFA composition is unknown.

OBJECTIVE

The objective was to test the effect of acute elevation of NEFAs enriched with either saturated fatty acids (SFAs) or SFAs with long-chain (LC) n-3 (omega-3) PUFAs on vascular function measured via flow-mediated dilatation (FMD), laser Doppler iontophoresis (LDI), and digital volume pulse (DVP).

DESIGN

In 59 subjects (30 men and 29 women), repeated oral fat feeding of either palm stearin (SFA) or palm stearin with DHA-rich fish oil (SFA + LC n-3 PUFA) was performed on 2 separate occasions with continuous heparin infusion to elevate NEFAs for a duration of 60 to 240 min. Vascular function was measured at baseline and at the end of NEFA elevation; venous blood was collected for measurement of lipids and circulating markers of endothelial function.

RESULTS

NEFA elevation during consumption of the SFA-rich drinks was associated with a marked impairment of FMD, whereas consumption of SFAs + LC n-3 PUFAs improved FMD response, with a mean (±SEM) difference of 2.06 ± 0.29% (P < 0.001). Positive correlations were found with percentage weight of LC n-3 PUFAs in circulating NEFAs and change in FMD response [Spearman's rho (r(s)) = 0.460, P < 0.001]. LDI measures increased during both treatments (P ≤ 0.026), and there was no change in DVP indexes.

CONCLUSIONS

The composition of NEFAs can acutely affect FMD. The beneficial effect of LC n-3 PUFAs on postprandial vascular function warrants further investigation but may be mediated by nitric oxide-independent mechanisms. This trial is registered at clinicaltrials.gov as NCT01351324.

Association of cardio-ankle vascular index with physical fitness and cognitive symptoms in aging Finnish firefighters

PURPOSE

Monitoring cardiovascular risk factors is important in health promotion among firefighters. The assessment of arterial stiffness (AS) may help to detect early signs of atherosclerosis. The aim of this study was to analyze associations between aerobic fitness, cognitive symptoms and cardio-ankle vascular index (CAVI) as a measure for AS among Finnish firefighters.

METHODS

The data are one part of a large 13-year follow-up study of the health and physical and mental capacity of Finnish professional firefighters. The subjects in this substudy comprised 65 male firefighters of a mean age of 48.0 (42-58) years in 2009. Their maximal oxygen uptake was successfully measured in two cross-sectional studies in 1996 and 2009, and they responded to questionnaires at both sessions, and their CAVI was measured in 2009. CAVI was calculated from the pulse waveform signal and pulse wave velocity. The lifestyle habits and subjective cognitive stress-related symptoms were collected via a standardized questionnaire. Muscular fitness was measured by the routine test battery used for Finnish firefighters.

RESULTS

CAVI was related to age. About one-fifth of the firefighters had a CAVI of >8. Aerobic fitness was the main physiological factor correlating with increased CAVI. Interestingly, VO(2)max and the accelerated decrease in VO(2)max during a 13-year follow-up were associated with signs of impaired vascular function. The cognitive symptoms derived from the Profile of Mood States questionnaire (POMS) were mainly associated with stress and sleeping difficulties. No clear association with physical fitness was found in this population of fit firefighters.

CONCLUSIONS

Among firefighters, the decrease in aerobic fitness predicts increased arterial stiffness. The speed of the age-related decline in maximal oxygen consumption is as important as absolute level. Against expectations, the cognitive function did not correlate with vascular health parameters. The cognitive symptoms, however, were only mild.

Presence of retinopathy in type 1 diabetic patients is associated with subclinical macroangiopathy

PURPOSE

The aim of the study was to assess the relationships between diabetic retinopathy, subclinical atherosclerosis and wave reflection in type 1 diabetic patients.

METHODS

The investigation involved 87 type 1 diabetic patients aged 34 years (interquartile range [IQR]: 29-43), with a disease duration of 10 years (IQR: 9-14). Of these 39 (45%) had diabetic retinopathy. Carotid intima-media thickness (CIMT) was measured using high resolution ultrasonography. Wave reflection and central hemodynamics [central (CAI(x)) and peripheral augmentation index (PAI(x))] were determined with the use of tonometry.

RESULTS

Patients with retinopathy compared to those without had increased CIMT (530 vs 480 μm, p = 0.017) and wave reflection (CAI(x) [118.90 vs 110.96 %, p = 0.03] and PAI(x) [64.95 vs 57.44 %, p = 0.029]). In logistic regression analysis, patient's age, duration of diabetes, systolic and diastolic blood pressure, postprandial glycemia, HbA1c value, CIMT (p = 0.017), CAI(x) (p = 0.03) and PAI(x) (p = 0.016) were associated with the presence of diabetic retinopathy. However, in the multivariate model, CIMT and CAI(x) did not remain predictors of retinopathy.

CONCLUSIONS

We have shown that the presence of retinopathy in type 1 diabetic patients is associated with subclinical atherosclerosis and wave reflection.

Evaluation of intima-media thickness and vascular elasticity of the common carotid artery in patients with isolated systolic hypertension using ultrasound radiofrequency-data technology

BACKGROUND

Radiofrequency (RF) data technology is a newly developed method to evaluate vascular disease, especially subclinical atherosclerotic change. Data regarding predictors of intima-media thickness (IMT) and vascular elasticity of the common carotid artery (CCA) in subjects with isolated systolic hypertension (ISH) using ultrasound RF-data technology are scarce.

AIMS

We evaluated the change in IMT and vascular elasticity of the CCA in patients with ISH at an early phase using US RF-data technology.

METHODS

Thirty-nine patients with ISH and 41 age-matched control subjects were the study population. The common carotid arterial systolic diameter (Ds), diastolic diameter (Dd), IMT, carotid distensibility (CD), local pulse wave velocity (PWVβ) and stiffness (β) were compared between the two groups, as were correlations between pulse pressure (PP) and parameters of vascular stiffness.

RESULTS

Common carotid arterial Ds, Dd, IMT, PWVβ and β increased whereas CD decreased more significantly in the ISH group than in age-matched controls. The level of PP in the ISH group had significant positive correlations with PWVβ (r = 0·298, P<0·05) and β (r = 0·291, P<0·05), whereas significant correlations with CD were not observed.

CONCLUSIONS

US RF-data technology could be used to accurately and quantitatively evaluate increased IMT and decreased arterial elasticity of the CCA in patients with ISH compared with normal subjects.

Acute effects of elevated NEFA on vascular function: a comparison of SFA and MUFA

There is emerging evidence to show that high levels of NEFA contribute to endothelial dysfunction and impaired insulin sensitivity. However, the impact of NEFA composition remains unclear. A total of ten healthy men consumed test drinks containing 50 g of palm stearin (rich in SFA) or high-oleic sunflower oil (rich in MUFA) on separate occasions; a third day included no fat as a control. The fats were emulsified into chocolate drinks and given as a bolus (approximately 10 g fat) at baseline followed by smaller amounts (approximately 3 g fat) every 30 min throughout the 6 h study day. An intravenous heparin infusion was initiated 2 h after the bolus, which resulted in a three- to fourfold increase in circulating NEFA level from baseline. Mean arterial stiffness as measured by digital volume pulse was higher during the consumption of SFA (P < 0·001) but not MUFA (P = 0·089) compared with the control. Overall insulin and gastric inhibitory peptide response was greater during the consumption of both fats compared with the control (P < 0·001); there was a second insulin peak in response to MUFA unlike SFA. Consumption of SFA resulted in higher levels of soluble intercellular adhesion molecule-1 (sI-CAM) at 330 min than that of MUFA or control (P ≤ 0·048). There was no effect of the test drinks on glucose, total nitrite, plasminogen activator inhibitor-1 or endothelin-1 concentrations. The present study indicates a potential negative impact of elevated NEFA derived from the consumption of SFA on arterial stiffness and sI-CAM levels. More studies are needed to fully investigate the impact of NEFA composition on risk factors for CVD.

Common Carotid Artery Intima-media Thickness is not Increased but Distensibility is Reduced in Normotensive Patients with Type 2 Diabetes compared with Control Subjects

This study evaluated carotid artery parameters in normotensive patients with type 2 diabetes compared with non-diabetic control subjects. Using a high-resolution B-mode ultrasound scanner, common carotid artery intima-media thickness (IMT) and carotid tree atheroma thickness were measured in 82 patients with type 2 diabetes and 41 controls. The distensibility of the common carotid artery was calculated using the Reneman equation. Distensibility was significantly decreased and atheroma thickness was significantly increased in the diabetes group. There was no significant difference in IMT between the two groups. Stepwise linear regression analysis revealed an association between common carotid artery distensibility and post-ischaemic dilatation of the brachial artery (a measure of endothelial function), body mass index and diabetes duration in patients with type 2 diabetes. In conclusion, common carotid artery IMT in normotensive patients with type 2 diabetes is comparable to that of control subjects, whereas atheroma thickness is higher and arterial stiffness more pronounced in those with type 2 diabetes, indicating the existence of atherosclerotic changes in normotensive type 2 diabetes patients.

The relationship between brachial ankle pulse wave velocity and complement 1 inhibitor

Complement 1 (C1) inhibitor is an acute phase protein with anti-inflammatory properties. The aim of the present study was to elucidate the relationship between brachial ankle pulse wave velocity (baPWV), the parameter of arterial stiffness, and C1 inhibitor. One hundred subjects were randomly enrolled in this study. Data about baPWV, age, gender, hypertension, smoking, and body mass index (BMI) were measured. Blood tests for total cholesterol, low density lipoprotein, high density lipoprotein, triglycerides, hemoglobin A1c, erythrocyte sedimentation rate, C-reactive protein, complement 3, and C1 inhibitor were performed. Based on the Pearson correlation, the C1 inhibitor showed a positive relation to the baPWV (P<0.001). Multiple regression analysis revealed the significant predictors of baPWV were not only the conventional risk factors of arteriosclerosis and/or atherosclerosis, such as age (P<0.001), gender (P<0.001), hypertension (P<0.001), and BMI (P=0.006), but also the acute phase protein, C1 inhibitor (P=0.025). In conclusion, C1 inhibitor is associated with arterial stiffness through its association with increased inflammation.

An association between the methylenetetrahydrofolate reductase (MTHFR) C677T mutation and inflammation markers related to cardiovascular disease

BACKGROUND

Prospective studies have identified many markers of systemic inflammation that are powerful predictors of future cardiovascular events. The methylenetetrahydrofolate reductase (MTHFR) C677T genotype, a common polymorphism that induces hyperhomocysteinaemia, has been proposed as a genetic risk factor for cardiovascular disease. In this work, we evaluated the relationship between the levels of inflammation markers and MTHFR genotype among cardiovascular disease free subjects of the ATTICA study.

METHODS

During 2001-2002, we randomly enrolled for genetic evaluation 574 subjects from Attica region, Greece. In this work, we investigated demographic, lifestyle, clinical, biochemical and genetic information from 322 men (46+/-13 years) and 252 women (45+/-14 years). Among other characteristics, we measured various inflammatory markers levels in relation to C677T MTHFR genotype distribution.

RESULTS

The MTHFR genotypes distribution was: homozygous normal (CC) genotype, 41%; heterozygous (CT), 48%; and homozygous mutant (TT) genotype, 11%. C-reactive protein (CRA), fibrinogen, white blood cell (WBC) counts and amyloid-a levels were higher in TT compared to CC and CT genotypes (p<0.01), in both genders, even after controlling for various potential confounders.

CONCLUSION

The observed association between markers of systemic inflammation with MTHFR genotype may state a hypothesis for a common pathobiological mechanism between inflammation process and MTHFR, which is a key enzyme in homocysteine (Hcy) metabolism.