Large Artery Stiffness Is Not Related to Plasma Cholesterol in Older Subjects with Hypertension

Association Between Triglycerides, High-Density Lipoprotein Cholesterol, and Their Ratio With the Pulse Wave Velocity in Adults From the ELSA-Brasil Study

Atherogenic dyslipidemia is a risk factor for cardiovascular diseases. The present study aimed to evaluate the association between triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and the triglycerides to high-density lipoprotein (TG/HDL-C) ratio with carotid-femoral pulse wave velocity (cf-PWV), a marker of vascular stiffness. Anthropometric, biochemical, and clinical data from 13,732 adults were used to assess this association. Individuals within the third TG/HDL-C tertile presented worse anthropometric, biochemical, and clinical profiles as compared with the participants in the lower TG/HDL-C tertile. There was a linear association between TG, HDL-C, and TG/HDL-C ratio and cf-PWV in both men and women (stronger in women). After adjustment for confounders, lower levels of HDL-C were associated with increased cf-PWV in men (9.63 ± .02 m/s) and women (8.90 ± .03 m/s). However, TG was not significantly associated with cf-PWV after adjustment, regardless of sex. An increased TG/HDL-C ratio is associated with higher cf-PWV only in women (9.01 ± .03 m/s), but after adjustment for HDL-C levels, the association was non-significant (8.99 ± .03 m/s). These results highlight the stronger association of HDL-C with arterial stiffness, and that the association of TG/HDL-C with cf-PWV is dependent on HDL-C.

Differential Roles of Life-Course Cumulative Burden of Cardiovascular Risk Factors in Arterial Stiffness and Thickness

BACKGROUND

Data are limited regarding differential and common effects of cardiovascular risk factors on subclinical changes in vascular structure and function. We aimed to examine the relationships of life-course cumulative burdens of cardiovascular risk factors with adult arterial pulse wave velocity (PWV) and carotid intima-media thickness (CIMT) in a longitudinal cohort of the Bogalusa Heart Study.

METHODS

The cohort consisted of 900 subjects who had aortic-femoral PWV and CIMT measurements. These participants were examined 5-16 times for body mass index (BMI), blood pressure, atherogenic index of plasma (AIP), and low-density lipoprotein cholesterol (LDLC) from childhood to adulthood. The area under the curve (AUC) was calculated as a measure of long-term burden of the risk factors.

RESULTS

Adjusting for covariates, adult PWV was associated with AUCs of BMI, systolic blood pressure (SBP) and AIP (standardized regression coefficient [β] = 0.191, 0.321, 0.153, respectively; P < 0.001 for all). Adult CIMT was associated with AUCs of BMI, SBP, AIP and LDLC (β = 0.115, 0.202, 0.141, 0.152, respectively; P < 0.001 for all). Moreover, childhood BMI was associated with adult PWV and CIMT (β = 0.088 and 0.075, respectively; false discovery rate q values < 0.05 for both), and childhood LDLC with adult CIMT (β = 0.079; false discovery rate q value < 0.05). These associations did not differ significantly among race and sex groups.

CONCLUSIONS

The life-course cumulative burden of BMI, SBP, and AIP has common effects on arterial wall stiffening and thickening, whereas LDLC is specifically associated with arterial wall thickness, and this effect starts in early life.

Local elasticity of the aorta in patients with type 2 diabetes mellitus

Objective

Arterial elasticity is important for assessing the state of an artery. This cross-sectional study aimed to non-invasively examine stiffness parameters of the ascending aorta in patients with type 2 diabetes mellitus (T2DM).

Methods

We studied 58 patients, including 38 with T2DM and 20 controls. The stiffness of the aorta was evaluated during transthoracic echocardiography. Aortic parameters of stiffness, such as the stiffness index, elasticity index, and compliance index, were calculated using the aortic maximal diameter, aortic minimal diameter, and blood pressure.

Results

Pulse pressure values were significantly higher patients with T2DM than in controls. The β index was significantly higher in patients with T2DM lasting for >7 years compared with those with T2DM lasting for <7 years. Mean aortic compliance was significantly lower in patients with a longer duration of diabetes than in those with a shorter duration of diabetes. Aortic elasticity was significantly lower in patients with diabetes and arterial hypertension compared with patients without diabetes with concomitant arterial hypertension.

Conclusions

Patients with T2DM, especially when T2DM is long-term, have increased stiffness and decreased compliance of the ascending aorta. Pulse pressure, which is a cardiovascular risk factor, is also significantly increased in patients with T2DM.

Can we IMPROVE cardiovascular outcomes through phosphate lowering in CKD? Rationale and protocol for the IMpact of Phosphate Reduction On Vascular End-points in Chronic Kidney Disease (IMPROVE-CKD) study

INTRODUCTION

Patients with chronic kidney disease (CKD) are at heightened cardiovascular risk, which has been associated with abnormalities of bone and mineral metabolism. A deeper understanding of these abnormalities should facilitate improved treatment strategies and patient-level outcomes, but at present there are few large, randomised controlled clinical trials to guide management. Positive associations between serum phosphate and fibroblast growth factor 23 (FGF-23) and cardiovascular morbidity and mortality in both the general and CKD populations have resulted in clinical guidelines suggesting that serum phosphate be targeted towards the normal range, although few randomised and placebo-controlled studies have addressed clinical outcomes using interventions to improve phosphate control. Early preventive measures to reduce the development and progression of vascular calcification, left ventricular hypertrophy and arterial stiffness are crucial in patients with CKD.

METHODS AND ANALYSIS

We outline the rationale and protocol for an international, multicentre, randomised parallel-group trial assessing the impact of the non-calcium-based phosphate binder, lanthanum carbonate, compared with placebo on surrogate markers of cardiovascular disease in a predialysis CKD population-the IM pact of P hosphate R eduction O n V ascular E nd-points (IMPROVE)-CKD study. The primary objective of the IMPROVE-CKD study is to determine if the use of lanthanum carbonate reduces the burden of cardiovascular disease in patients with CKD stages 3b and 4 when compared with placebo. The primary end-point of the study is change in arterial compliance measured by pulse wave velocity over a 96-week period. Secondary outcomes include change in aortic calcification and biochemical parameters of serum phosphate, parathyroid hormone and FGF-23 levels.

ETHICS AND DISSEMINATION

Ethical approval for the IMPROVE-CKD trial was obtained by each local Institutional Ethics Committee for all 17 participating sites in Australia, New Zealand and Malaysia prior to study commencement. Results of this clinical trial will be published in peer-reviewed journals and presented at conferences.

TRIAL REGISTRATION NUMBER

ACTRN12610000650099.

Markers of arterial stiffness in a sample of Lebanese subjects with Grade I essential hypertension

Objectives:

Arterial stiffness is becoming a major global condition associated with an increased risk of cardiovascular problems and death. Several markers have been linked to arterial stiffness.

Methods:

To determine and evaluate these relations, anthropometric parameters (weight, height, and pulse rate), biochemical profile, and central and peripheral indices of arterial function were measured in 114 Lebanese subjects with Grade I essential hypertension.

Results:

Age was associated with a higher pulse wave velocity (p = .001), central systolic blood pressure (p = .013), central pulse pressure (p = .028), central augmentation index (p ≤ .0001) with a lower heart rate (p = .08), and glomerular filtration rate (p = .019). Pulse wave velocity was found to be higher in older subjects (>65 years) and correlated with higher body mass index (r = .85) independent of age. Aging also correlated with higher plasma glucose and alterations in calcium–phosphorus metabolism.

Conclusion:

Aging is associated with increased arterial stiffness which is reflected by an increase in the pulse wave velocity, augmentation index, central pulse pressure, and central systolic blood pressure with a reduction in heart rate. Also, a higher body mass index and a lower estimated glomerular filtration rate (< 60 mL/min/1.73 m²) are associated with increased arterial stiffness while calcium and phosphorus metabolism may play a role by promoting vascular calcification.

Aortic stiffness and left ventricular function in patients with differentiated thyroid cancer

OBJECTIVE

The aim of this study was to investigate aortic stiffness and left ventricular (LV) systolic and diastolic function in patients with differentiated thyroid cancer (DTC) on thyroxine (L-T4) therapy and after L-T4 withdrawal to assess the cardiovascular impact of long-term subclinical hyperthyroidism and short-term overt hypothyroidism.

METHODS

Twenty-four patients who had had total thyroidectomy and radioiodine ablation for differentiated thyroid cancer were studied on two occasions: on TSH suppressive L-T4 therapy (sTSH 0.24 ± 0.11 mU/L), and 4 weeks after L-T4 withdrawal (sTSH 89.82 ± 29.36 mU/L). Echocardiography was performed and thyroid function, serum thyroglobulin, lipid parameters, homocystine, C-reactive protein, fibrinogen and von Willebrand factor activity (vWF) were measured. Twenty-two healthy volunteers matched for age and sex served as euthyroid controls.

RESULTS

Aortic stiffness was increased both in hypothyroidism (6.04 ± 2.88 cm(2)/dyn/10(3), p < 0.05) and subclinical hyperthyroidism (9.27 ± 4.81 cm(2)/dyn/10(3), p < 0.05) vs. controls (3.92 ± 1.84 cm(2)/dyn/10(3)). Subclinical hyperthyroidism had a more marked effect (p < 0.05). LV dimensions and ejection fractions were similar before and after L-T4 withdrawal. The E'/A' was higher in euthyroid controls (1.34 ± 1.02) as compared to both subclinical hyperthyroidism (1.0 ± 0.14, p < 0.05) and overt hypothyroidism (1.13 ± 0.98, p < 0.05). Change of aortic stiffness correlated with change of free-thyroxine (fT4), vWF and fibrinogen levels in a positive manner.

CONCLUSION

Long-term thyrotropin-suppression therapy has continuous adverse effects on the arterial wall. The degree of TSH suppression in patients with DTC should be kept at the possible minimum, based on individually determined potential benefits and risks of treatment, especially in patients with cardiovascular co-morbidities.

Relationships between HDL-C, hs-CRP, with central arterial stiffness in apparently healthy people undergoing a general health examination

Background

Some cardiovascular risk factors have been confirmed to be positively correlated with arterial stiffness. However, it is unclear whether HDL-C, a well-established anti-risk factor, has an independent association with arterial stiffness. The aim of this study was to evaluate the relationship between HDL-C levels and arterial stiffness and the possible role of high-sensitivity C-reactive protein (hs-CRP) in this potential correlation in apparently healthy adults undergoing a general health examination in China.

Materials and Methods

This was a cross-sectional survey. In total, 15,302 participants (age range, 18–82 years; mean, 43.88±8.44 years) were recruited during routine health status examinations. A questionnaire was used and we measured the body mass index, systolic and diastolic blood pressure, and fasting glucose, and serum lipid, uric acid, hs-CRP, and serum creatinine levels of each participant. Central arterial stiffness was assessed by carotid–femoral pulse wave velocity (cf-PWV).

Results

HDL-C levels decreased as cf-PWV increased. Pearson’s correlation analysis revealed that HDL-C levels were associated with cf-PWV (r=−0.18, P<0.001). hs-CRP levels were positively associated with cf-PWV (r=0.13). After adjustment for all confounders, HDL-C was inversely independently associated with all quartiles of cf-PWV. Furthermore, HDL-C was associated with cf-PWV in different quartiles of hs-CRP, and the correlation coefficients (r) gradually decreased with increasing hs-CRP levels (quartiles 1–4).

Conclusions

HDL-C is inversely independently associated with central arterial stiffness. The anti-inflammatory activity of HDL-C may mediate its relationship with cf-PWV. Further, long-term follow-up studies are needed to evaluate whether high HDL-C levels are protective against central artery stiffening through the anti-inflammatory activity of HDL-C.

Blood pressure tracking over the adult life course: patterns and correlates in the Framingham heart study

The extent to which select vascular risk factors differentially influence blood pressure (BP) is incompletely understood. Thus, we used multilevel modeling to analyze serial BP measurements using 21 732 person-observations obtained on Framingham Heart Study participants (mean age, 38 years, 52% women; 4993 unique individuals) over a 28-year period. We related longitudinal tracking of each BP measure (systolic BP, diastolic BP, mean arterial pressure, and pulse pressure) to age, sex, body mass index, smoking, diabetes mellitus, total/high-density lipoprotein cholesterol ratio, and heart rate. In multivariable-adjusted analyses, we observed that older age, male sex, greater body mass index, and higher heart rate were positively associated with increase in all BP measures (P<0.0001). Notably, higher total/high-density lipoprotein cholesterol ratio was associated with greater mean arterial pressure (P<0.01). Conversely, diabetes mellitus and smoking were associated with higher pulse pressure (P<0.01). We also observed effect modification by sex: the increase in pulse pressure with age and body mass index was more pronounced in women compared with men (P<0.0001). All BP measures tracked at higher levels in both men and women with multiple vascular risk factors. Taken together, our longitudinal observations in a large community-based sample demonstrate a greater pulsatile load in women than in men with increasing age. We also observed a differential impact of select vascular risk factors on the individual components of BP, underscoring distinct regulation of these measures over the life course.

Differential impact of heart rate on arterial wall stiffness and thickness in young adults: The Bogalusa Heart Study

Heart rate, a hemodynamic parameter, is an important determinant of arterial wall stiffness. However, information on the relationship of heart rate to arterial wall thickness is inconsistent. This study examined the influence of heart rate on arterial stiffness and thickness in Black and White young adults. The study cohort consisted of 255 Black and 659 White adults age 25 to 43 years enrolled in the Bogalusa Heart Study. Carotid artery intima-media thickness (IMT) was measured by B-mode ultrasound and aorta-femoral pulse wave velocity (af-PWV) by echo-Doppler. There was no difference in heart rate between Blacks and Whites. Males vs. females displayed lower heart rate and higher segmental and composite carotid IMT; Blacks vs. Whites had higher composite carotid IMT (0.83 mm vs. 0.80 mm, P < .01) and af-PWV (5.4 m/s vs. 5.2 m/s, P < .01). In a multivariate regression model adjusting for traditional cardiovascular risk variables, heart rate was independently associated with af-PWV (standardized regression coefficient: beta = .14, P = .01 for Blacks; beta = .06, P = .07 for Whites; beta = .09, P = .003 for total sample), but not with carotid IMT. These results indicate that heart rate plays differential roles in the development of arterial stiffness and subclinical atherosclerosis during young adulthood.

Association between Endothelial Biomarkers and Arterial Elasticity in Young Adults - The CARDIA Study

BACKGROUND

Reduced arterial elasticity and endothelial dysfunction both may indicate early cardiovascular (CV) disease in young adults. Pulse waveform analysis estimates large (LAE) and small (SAE) artery elasticity noninvasively. We assessed the associations between LAE and SAE and markers of endothelial dysfunction and CV risk factors.

METHODS

The Coronary Artery Risk Development in Young Adults (CARDIA) assessed arterial elasticity and other characteristics cross-sectionally in 389 men and 381 women aged 27-42 years in 1995 (CARDIA year 10) and circulating levels of P-selectin and soluble intercellular adhesion molecule 1 (sICAM-1) in 2000. We adjusted for variables included in the estimation of arterial elasticity (year 10 height, body mass index, age, heart rate, and blood pressure) and other year 10 characteristics.

RESULTS

Mean adjusted SAE was 8.5 vs. 7.6 ml/mmHg x100 in those with urine albumin/creatinine ratio </=4 vs. microalbuminuria (ratio > 25; p(trend) =0.008). Mean LAE was 25.6 vs. 24.2 ml/mmHg x10 in the lowest vs. highest quintile of P-selectin (p(trend) =0.004). sICAM-1 was unrelated to either LAE or SAE. Plasma triglycerides were inversely related to LAE (p(trend) =0.029). Cigarette smokers had lower SAE than nonsmokers (p(trend) = 0.009).

CONCLUSION

In addition to smoking and triglycerides, biomarkers for endothelial dysfunction were associated with impaired LAE and SAE in young adults.

Association of serum lipids with arterial stiffness in a population-based study in Beijing

BACKGROUND

Some cardiovascular risk factors such as age, hypertension and diabetes have been confirmed to be positively correlated with arterial stiffness. However, the relationship between serum lipids and arterial stiffness is incompletely understood. Recent studies have been far from conclusive and consistent data were not obtained. We investigated the relationship between serum lipids and pulse wave velocity (PWV) in community-dwelling individuals in Beijing, China.

METHODS

This was a population-based, cross-sectional sample of adults (n = 2375; 48·1% men; age range, 40-96 years) from two communities in Beijing. A questionnaire was used for the risk factors of arterial stiffness. Anthropometry, blood pressure and heart rate were measured. Values of fasting plasma glucose (FPG), serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and uric acid were measured. Carotid-femoral PWV (cfPWV) and carotid-radial PWV (crPWV) were assessed non-invasively.

RESULTS

Carotid-femoral pulse wave velocity was significantly positively related to TC (r = 0·221; P < 0·0001), LDL-C (r = 0·193; P < 0·0001) and inversely related to HDL-C (r = -0·240; P < 0·0001), but not with TG (r = 0·073; P = 0·6721). crPWV was inversely related to HDL-C (r = -0·272; P < 0·0001), but not with TC (r = 0·007; P = 0·4781), LDL-C (r = 0·021; P = 0·6393) or TG (r = 0·008; P = 0·2498). The multiple regression analysis showed that LDL-C was independently associated with cfPWV and that HDL-C was inversely associated with cfPWV and crPWV. TC and TG were not independently related to cfPWV and crPWV.

CONCLUSIONS

These data show the correlation between some of the parameters of serum lipids and arterial stiffness. LDL-C was independently associated with aortic stiffness, and HDL-C was independently inversely associated with aortic stiffness and peripheral stiffness.

The assessment of vascular function during dietary intervention trials in human subjects

The potential to reduce cardiovascular morbidity through dietary modification remains an area of intense clinical and scientific interest. Any putatively beneficial intervention should be tested within a randomised controlled trial which records appropriate endpoints, ideally incident CVD and death. However, the large sample sizes required for these endpoints and associated high costs mean that the majority of dietary intervention research is conducted over short periods among either healthy volunteers or those at only slightly increased risk, with investigators using a diverse range of surrogate measures to estimate arterial health in these studies. The present review identifies commonly employed techniques, discusses the relative merits of each and highlights emerging approaches.

The macrocirculation and microcirculation of hypertension

Changes in vascular structure that accompany hypertension may contribute to hypertensive end-organ damage. Both the macrovascular and microvascular levels should be considered, as interactions between them are believed to be critically important. Regarding the macrocirculation, the article first reviews basic concepts of vascular biomechanics, such as arterial compliance, arterial distensibility, and stress-strain relationships of arterial wall material, and then reviews how hypertension affects the properties of conduit arteries, particularly examining evidence that it accelerates the progressive stiffening that normally occurs with advancing age. High arterial stiffness may increase central systolic and pulse pressure by two different mechanisms: 1) Abnormally high pulse wave velocity may cause pressure waves reflected in the periphery to reach the central aorta in systole, thus augmenting systolic pressure; 2) In the elderly, the interaction of the forward pressure wave with high arterial stiffness is mostly responsible for abnormally high pulse pressure. At the microvascular level, hypertensive disease is characterized by inward eutrophic or hypertrophic arteriolar remodeling and capillary rarefaction. These abnormalities may depend in part on the abnormal transmission of highly pulsatile blood pressure into microvascular networks, especially in highly perfused organs with low vascular resistance, such as the kidney, heart, and brain, where it contributes to hypertensive end-organ damage.

Impact of Statin Therapy on Central Aortic Pressures and Hemodynamics

Background— Statins reduce the risk of cardiovascular events in people with hypertension. This benefit could arise from a beneficial effect of statins on central aortic pressures and hemodynamics. The Conduit Artery Function Evaluation–Lipid-Lowering Arm (CAFE-LLA) study, an Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT) substudy, investigated this hypothesis in a prospective placebo-controlled study of treated patients with hypertension.

Methods and Results— CAFE-LLA recruited 891 patients randomized to atorvastatin 10 mg/d or placebo from 5 centers in the United Kingdom and Ireland. Radial artery applanation tonometry and pulse-wave analysis were used to derive central aortic pressures and hemodynamic indices at repeated visits over 3.5 years of follow-up. Atorvastatin lowered low-density lipoprotein cholesterol by 32.4 mg/dL (95% confidence interval [CI], 28.6 to 36.3) and total cholesterol by 35.1 mg/dL (95% confidence interval, 30.9 to 39.4) relative to placebo. Time-averaged brachial blood pressure was similar in CAFE-LLA patients randomized to atorvastatin or placebo (change in brachial systolic blood pressure, −0.1 mm Hg [95% CI, −1.8 to 1.6], P =0.9; change in brachial pulse pressure, −0.02 mm Hg [95% CI, −1.6 to 1.6], P =0.9). Atorvastatin did not influence central aortic pressures (change in aortic systolic blood pressure, −0.5 mm Hg [95% CI, −2.3 to 1.2], P =0.5; change in aortic pulse pressure, −0.4 mm Hg [95% CI, −1.9 to 1.0], P =0.6) and had no influence on augmentation index (change in augmentation index, −0.4%; 95% CI, −1.7 to 0.8; P =0.5) or heart rate (change in heart rate, 0.25 bpm; 95% CI, −1.3 to 1.8; P =0.7) compared with placebo. The effect of statin or placebo therapy was not modified by the blood pressure–lowering treatment strategy in the factorial design.

Conclusions— Statin therapy sufficient to significantly reduce cardiovascular events in treated hypertensive patients in ASCOT did not influence central aortic blood pressure or hemodynamics in a large representative cohort of ASCOT patients in CAFE-LLA.

Relation of aortic wall thickness and distensibility to cardiovascular risk factors (from the Multi-Ethnic Study of Atherosclerosis [MESA])

To determine the relation between aortic wall thickness (WT) and aortic distensibility (AD) with traditional cardiovascular risk factors in the Multi-Ethnic Study of Atherosclerosis (MESA) cohort, 1,053 participants in MESA who underwent cardiac magnetic resonance imaging were consecutively selected for the measurement of aortic WT and AD. Double inversion-recovery fast spin-echo images of the thoracic aorta were obtained to measure average and maximum WT. AD was measured at the same level using a gradient-echo cine sequence. Average and maximum WT were positively correlated with increasing age, and AD was inversely related to age (p <0.01). Compared with normotensive participants, those with hypertension had significantly greater mean average WT (2.45 vs 2.23 mm, p <0.01) and maximum WT (3.61 vs 3.41 mm, p <0.01) and lower AD (0.15 vs 0.2 mm Hg(-1), p <0.01). In multiple regression analysis, older age and hypertension were significantly associated with higher mean average WT, while older age, male gender, and higher blood pressure were associated with higher mean maximum WT. AD was inversely related to older age, hypertension, current smoking, African American ethnicity, and lower high-density lipoprotein cholesterol level. In conclusion, in the MESA cohort, older age and higher blood pressure were associated with higher aortic WT and lower AD. Decreased AD was further associated with current smoking, African American ethnicity, and higher high-density lipoprotein cholesterol level.

Smaller aortic dimensions do not fully account for the greater pulse pressure in elderly female hypertensives

This study examined the importance of aortic dimensions in determining pulse pressure in elderly hypertensives participating in the 2nd Australian National Blood Pressure Study, including a substantial number not previously receiving blood pressure lowering medication. Aortic dimensions were determined by ultrasound at the transverse arch and at the insertion of the aortic valve. Unadjusted data showed negative (P<0.001) correlations between central (carotid) and (brachial) peripheral pulse pressure and both arch (-0.200, -0.181) and outflow tract (-0.238, -0.238) diameters. Correlations were similar in those previously treated with blood pressure lowering medication and in the treatment naïve. Central pulse pressure (84+/-26 versus 75+/-28 mm Hg, P<0.001) was higher and aortic dimensions (transverse arch 2.56+/-0.31 versus 2.88+/-0.35 mm, P<0.001) smaller in women than men. Women had greater aortic stiffness (beta index 29.4+/-36.1 versus 22.1+/-21.3, P<0.03). Other bivariate correlates of central pulse pressure were age, mean arterial pressure, height, heart rate, augmentation index, aortic stiffness (all P<0.001), and weight (P=0.027). In multivariate analyses gender remained a predictor of central pulse pressure (P<0.001) even with inclusion of aortic dimensions (P=0.013) height and weight. Other significant terms were age, heart rate, mean blood pressure, and aortic stiffness (all P<0.001). These findings demonstrate an independent inverse relation between aortic size and pulse pressure in older hypertensive subjects. Differences in aortic dimensions and stiffness between genders do not fully account for the observed blood pressure differences, suggesting that a contributory factor to gender differences in pulse pressure is an increased age-related mismatch in ventricular function and aortic stiffness in women compared with men.

Endothelial function, arterial stiffness and lipid lowering drugs

The endothelium is a dynamic organ that plays a pivotal role in cardiovascular homeostasis. Alteration in endothelial function precedes the development of atherosclerosis and contributes to its initiation, perpetuation and clinical manifestations. It has been suggested that the assessment of endothelial function could represent a barometer of vascular health that could be used to gauge cardiovascular risk. This review summarises the various methods used to assess endothelium-dependent vasodilatation and their potential prognostic implications. In addition, the techniques used to evaluate arterial stiffness are discussed. The latter is to some extent controlled by the endothelium and has been the subject of considerable research in recent years. This paper also discusses the effects of lipid lowering treatment on both endothelial function and arterial stiffness.

Vascular stiffness in familial hypercholesterolaemia is associated with C-reactive protein and cholesterol burden

BACKGROUND

Familial hypercholesterolaemia (FH) is characterized by very high serum cholesterol and premature coronary atherosclerosis. Arterial stiffness and atherosclerosis are two major underlying pathophysiologies of arterial disease that are predictive of future cardiovascular events. The aims of this study were to quantify atherosclerosis and arterial stiffness and to evaluate their relationship with high sensitive C-reactive protein (hs-CRP) and the level of exposure to high serum cholesterol in FH patients.

MATERIALS AND METHODS

We measured traditional risk factors, hs-CRP, intima-media thickness (IMT) of carotid artery, and brachial-ankle pulse wave velocity (baPWV) in 35 heterozygous FH subjects and 17 healthy control subjects. Cholesterol-year score (CYS) was calculated to estimate the lifetime cholesterol burden in FH subjects.

RESULTS

FH subjects had significantly elevated total cholesterol, low-density lipoprotein cholesterol, and carotid IMT compared with those without mutations. Among FH patients, the baPWV and carotid IMT were higher in cases with high cholesterol burden than those without. Similarly, the baPWV and carotid IMT were also higher in cases with elevated hs-CRP (> 1 mg L(-1)) than those without. Multiple linear regression analysis demonstrated CYS and hs-CRP were significant independent predictors of baPWV and IMT in FH patients.

CONCLUSIONS

Both high cholesterol burden and vascular inflammation are not only associated with atherosclerosis, but also contribute to the development of arterial stiffness in FH patients. Early detection of hypercholesterolaemia in FH patients is warranted to prevent the untoward pathophysiologies.

Ageing and vascular ageing

There is an age related decline in various physiological processes. Vascular ageing is associated with changes in the mechanical and the structural properties of the vascular wall, which leads to the loss of arterial elasticity and reduced arterial compliance. Arterial compliance can be measured by different parameters like pulse wave velocity, augmentation index, and systemic arterial compliance. There is evidence that arterial compliance is reduced in disease states such as hypertension, diabetes, and end stage renal failure. Changes in arterial compliance can be present before the clinical manifestation of cardiovascular disease. Pharmacological and non-pharmacological measures have been shown to improve arterial compliance. Arterial compliance may constitute an early cardiovascular risk marker and may be useful in assessing the effects of drugs on the cardiovascular system. Pharmacogenetics and genetics of arterial compliance in the future will improve our knowledge and understanding about vascular ageing.

RELATIONSHIP BETWEEN ARTERIAL STIFFNESS AND GLUCOSE METABOLISM IN WOMEN WITH METABOLIC SYNDROME

1. Cardiovascular risk factors associated with the metabolic syndrome affect vascular functions adversely. The aim of the present study was to assess the relationship between parameters of glucose homeostasis and arterial stiffness in women with characteristics of the metabolic syndrome. 2. Twenty post-menopausal women participated in a cross-sectional study in which systemic arterial compliance (SAC) and plasma glucose, lipids and glycosylated haemoglobin (HbA1c) were measured while subjects were maintained on a diet high in fibre, raised in protein and reduced in saturated fat. 3. Regression analysis suggested that mean ( +/-SD) fasting glucose of 5.9 +/- 1.7 mmol/L, glucose levels 2 h after a 75 g glucose load of 6.8 +/- 3.6 mmol/L, systolic blood pressure of 131 +/- 12 mmHg and HbA1c of 5.3 +/- 1.7% predicted SAC negatively. The following correlations were obtained between SAC and: (i) fasting glucose: R = -0.49, P = 0.028; (ii) 2 h glucose level post-glucose load: R = -0.42, P = 0.064; (iii) HbA1c: R = -0.42, P = 0.056; and (iv) systolic blood pressure: R = -0.55, P = 0.012. 4. Relationships between SAC and fasting glucose and systolic blood pressure were significantly independent of each other. There was no evidence of relationships between SAC and any plasma lipid parameter (other than a trend in relation to plasma triglyceride), bodyweight or waist circumference. 5. In conclusion, in post-menopausal women with metabolic syndrome, fasting plasma glucose and systolic blood pressure, and possibly HbA1c and the 2 h glucose post-glucose load, predicted increased arterial stiffness.

Determinants of arterial stiffness in an apparently healthy population over 60 years

Arterial stiffness assessed by the pulse wave velocity (PWV), a non-invasive and reproducible method, predicts cardiovascular morbidity and mortality. The main determinants of arterial stiffness are well established in younger and middle-aged populations, but much less in the elderly. The aim of this study was to describe the determinants of arterial stiffness in elderly apparently healthy subjects. The study included 221 voluntary subjects born before 1944 (mean age 67.4+/-5.0 years), who had a standard health check-up at the 'Centre de Médecine Préventive' of Nancy. Arterial stiffness was evaluated by measuring the carotid-femoral PWV with the PulsePen automatic device. Clinical and biological parameters were evaluated at the same day. Measurements were valid and analysed in 207 subjects (94 women). Mean PWV was 9.39+/-2.64 m/s. Men showed higher PWV values than women (9.99+/-2.56 vs 8.66+/-2.56, P<0.001). In univariate analysis, PWV was correlated with age (r=0.26, P<0.001) and mean arterial pressure (MAP) (r=0.40, P<0.001), and these relationships were similar in men and women. Subjects with hypertension (P<0.001), diabetes mellitus (P<0.001) and obesity (P<0.01) had higher values of PWV. In multiple regression analysis, PWV correlated positively and independently with age, male gender, MAP and diabetes mellitus. In conclusion, in an apparently healthy elderly population, the main determinants of arterial stiffness are the age, MAP, diabetes and gender. Our study also shows that the gender-related differences in arterial stiffness observed in middle-aged subjects are maintained in the elderly.

Non-invasively measured structural and functional arterial characteristics and coronary heart disease risk in middle aged and elderly men

BACKGROUND

In cardiovascular (CV) epidemiology, interest increases in studying etiologic and prognostic implications of early structural or functional changes of the large arteries. Examples of such measurements are pulse wave velocity (PWV), carotid intima-media thickness (CIMT) and augmentation index (AIx). PWV and CIMT are established markers of CV risk whereas the role of AIx as indicator of risk has not fully been established. Therefore, our aim was to relate AIx to CV risk and to compare the magnitude of relations of PWV, CIMT and AIx to CV risk.

METHODS

Two hundred and ninty-nine men free from cardiovascular disease (mean age 59.2 years), participated in this cross-sectional study. Cardiovascular risk profile was determined and 10-year coronary heart disease risk was estimated using the Framingham risk score (FRS). PWV, CIMT and AIx were measured and data were analyzed using linear regression models.

RESULTS

PWV and CIMT were strongest related to FRS whereas AIx showed the weakest relation. Ten-year coronary heart disease risk increased 6.24%, 95% confidence interval (CI) [5.11;7.37] per standard deviation (S.D.) increase in PWV, 6.39% [5.24;7.54] per S.D. increase in CIMT and 2.50% [1.19;3.80] per S.D. increase in AIx.

CONCLUSION

In middle aged and elderly men AIx is related to CV risk. However, compared with AIx, PWV and CIMT seem better markers of cardiovascular risk.

Different Effects of Atherogenic Lipoproteins and Blood Pressure on Arterial Structure and Function: The Bogalusa Heart Study

Differential impact of non-high-density lipoprotein cholesterol (total cholesterol minus high-density lipoprotein cholesterol) and blood pressure on arterial wall thickness and stiffness was examined in 900 black and white adults aged 24-43 years. Blacks compared with whites had greater values of pulse wave velocity (5.4 m/sec vs. 5.2 m/sec; p<0.01) and carotid artery intima-media thickness (0.83 mm vs. 0.80 mm; p<0.01). Non-high-density lipoprotein cholesterol was significantly associated with carotid intima-media thickness (standardized regression coefficient [b]=0.21; p<0.01), but not with pulse wave velocity (b=0.03; p=0.37), after adjusting for race, sex, age, body mass index, insulin, glucose, and smoking. Systolic blood pressure was associated significantly stronger with pulse wave velocity (b=0.36; p<0.01) than with carotid intima-media thickness (b=0.15; p<0.01). No race difference in these relationships was found. The results of this study indicate that atherogenic lipoproteins and blood pressure may play different roles in the development of arterial wall stiffness and atherosclerosis.

Alcohol and arterial wave reflections in middle aged and elderly men

BACKGROUND

Augmentation index (AIx) is a measure of arterial wave reflection, providing information on the workload of the heart. and is a possible marker for cardiovascular disease risk. The relation of alcohol consumption with cardiovascular disease (CVD) risk is U-shaped with a protective effect of moderate alcohol consumption. The relation of alcohol consumption level with AIx has not been widely investigated, which prompted this study of the relation of alcohol consumption with AIx in a population-based cohort of men aged 40-80 years.

METHODS

Three hundred and seventy-four men (mean age 60.5 years) participated in this cross-sectional study. Alcohol consumption and smoking habits were determined through a validated questionnaire. Fasting blood samples were drawn and analyzed for glucose and lipid levels and AIx was estimated by radial applanation tonometry using the SphygmoCor Device. The resultant data were analyzed using linear regression models.

RESULTS

Age, height, heart rate, blood pressure, packyears, current smoking, presence of CVD and hypertension were independently related to AIx. The relation of alcohol consumption with AIx was U-shaped, with a significantly lower AIx in the group drinking 4-8 glasses/week (difference = -2.91%, 95% CI [-5.65; -0.18]) relative to those drinking 0-3 glasses/week. Additional adjustment for current smoking did not change this relationship, but adjustment for pulse wave velocity attenuated the relation.

CONCLUSIONS

In a population-based cohort of men aged 40-80 years the relation of alcohol consumption level with AIx was U-shaped, further expanding the evidence for vascular protective effects of moderate alcohol intake.