The early life origins of vascular ageing and cardiovascular risk: the EVA syndrome

Oxidative stress and genetic markers of suboptimal antioxidant defense in the aging brain: a theoretical review

Normal aging involves a gradual breakdown of physiological processes that leads to a decline in cognitive functions and brain integrity, yet the onset and progression of decline are variable among older individuals. While many biological changes may contribute to this degree of variability, oxidative stress is a key mechanism of the aging process that can cause direct damage to cellular architecture within the brain. Oligodendrocytes are at a high risk for oxidative damage due to their role in myelin maintenance and production and limited repair mechanisms, suggesting that white matter may be particularly vulnerable to oxidative activity. Antioxidant defense enzymes within the brain, such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione-S-transferase (GST), are crucial for breaking down the harmful end products of oxidative phosphorylation. Previous studies have revealed that allele variations of polymorphisms that encode these antioxidants are associated with abnormalities in SOD, CAT, GPx, and GST activity in the central nervous system. This review will focus on the role of oxidative stress in the aging brain and the impact of decreased antioxidant defense on brain integrity and cognitive function. Directions for future research investigations of antioxidant defense genes will also be discussed.

Early accelerated senescence of circulating endothelial progenitor cells in premature coronary artery disease patients in a developing country - a case control study

Background

The decreased number and senescence of circulating endothelial progenitor cells (EPCs) are considered markers of vascular senescence associated with aging, atherosclerosis, and coronary artery disease (CAD) in elderly. In this study, we explore the role of vascular senescence in premature CAD (PCAD) in a developing country by comparing the numerical status and senescence of circulating EPCs in PCAD patients to controls.

Methods

EPCs were measured by flow cytometry in 57 patients with angiographically documented CAD, and 57 controls without evidence of CAD, recruited from random patients ≤ 50 years of age at All India Institute of Medical Sciences. EPC senescence as determined by telomere length (EPC-TL) and telomerase activity (EPC-TA) was studied by real time polymerase chain reaction (q PCR) and PCR– ELISA respectively.

Result

The number of EPCs (0.18% Vs. 0.039% of total WBCs, p < 0.0001), and EPC-TL (3.83 Vs. 5.10 kb/genome, p = 0.009) were markedly lower in PCAD patients compared to controls. These differences persisted after adjustment for age, sex, BMI, smoking and medications. EPC-TA was reduced in PCAD patients, but was statistically significant only after adjustment for confounding factors (1.81 Vs. 2.20 IU/cell, unadjusted p = 0.057, adjusted p = 0.044).

Conclusions

We observed an association between increased vascular cell senescence with PCAD in a sample of young patients from India. This suggests that early accelerated vascular cell senescence may play an important mechanistic role in CAD epidemic in developing countries like India where PCAD burden is markedly higher compared to developed countries.

Short-term administration of alibernet red wine extract failed to affect blood pressure and to improve endothelial function in young normotensive and spontaneously hypertensive rats

As wine polyphenols were shown to possess many positive effects in mammals, including improvement of vascular function, this study investigated the effect of the Slovak Alibernet red wine extract (AWE) on blood pressure and vascular function in young normotensive Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats. Six weeks old, male, WKY and SHR were treated with AWE for three weeks at the dose of 24.2 mg/kg/day. Blood pressure (BP), determined by tail-cuff plethysmography, was significantly elevated in SHR vs. WKY and AWE failed to affect it. Lipid peroxidation was evaluated by determination of thiobarbituric acid-reactive substances. Vascular function was assessed in rings of the femoral artery using Mulvany-Halpern's myograph. Maximal endothelium-dependent acetylcholine (ACh)-induced relaxation was reduced in control SHR vs. WKY rats by approximately 9.3 %, which was associated with a significant decrease of its NO-independent component. AWE failed to affect maximal ACh-induced relaxation, both its NO-dependent and independent components, compared to controls of the same genotype. AWE however reduced lipid peroxidation in the left ventricle of both WKY and SHR and in the liver of SHR. In conclusion, three-week administration of AWE failed to reduce BP and to improve endothelial function in the femoral arteries of both genotypes investigated.

Blood pressure and pulse wave velocity as metrics for evaluating pathologic ageing of the cardiovascular system

The influence of chronological ageing on the components of the cardiovascular system is of fundamental importance for understanding how hemodynamics change and the cardiovascular risk increases with age, the most important risk marker. An increase in peripheral vascular resistance associated with increased stiffness of central elastic arteries represents hallmarks of this ageing effect on the vasculature, referred to as early vascular ageing (EVA). In clinical practice, it translates into increased brachial and central systolic blood pressure and corresponding pulse pressure in subjects above 50 years of age, as well as increased carotid-femoral pulse wave velocity (c-f PWV)--a marker of arterial stiffness. A c-f PWV value ≥ 10 m/s is threshold for increased risk according. Improved lifestyle and control of risk factors via appropriate drug therapy are of importance in providing vascular protection related to EVA. One target group might be members of risk families including subjects with early onset cardiovascular disease.

Impact of obesity on cardiovascular health

This review examines the impact of obesity on cardiovascular health. We will review first, relationship between obesity and hypertension. Second, we will describe obesity-related subclinical abnormalities in cardiovascular function and structure. Third, we will summarize evidence linking obesity to overt cardiovascular disease including coronary artery disease, congestive heart failure, stroke, arrhythmias and sudden cardiac death. Fourth, we will discuss the potential mechanisms underlying increased cardiovascular risk in obese subjects. Last, we will discuss contribution of sleep apnea to the link between obesity and cardiovascular disease. Despite recent progress in understanding epidemiologic and pathophysiological links between obesity and cardiovascular disease, several issues remain to be addressed in the future studies. There is a clear need to identify better markers of obesity-related subclinical cardiovascular damage. Furthermore, we should improve identification of obese subjects at highest cardiovascular risk.

Determination of hyperelastic properties for umbilical artery in preeclampsia from uniaxial extension tests

OBJECTIVE

Preeclampsia often results in altered hemodynamics and structurally remodeled umbilical arteries in the fetus--alterations that may be associated with arterial stiffening. We therefore hypothesized that the mechanical function of preeclamptic (PE) umbilical arteries had increased stiffness compared to control.

STUDY DESIGN

Umbilical arteries were collected from control (n=9) and PE (n=6) pregnancies without any other complications. Samples were tested uniaxially in axial and circumferential directions for the passive mechanics. The umbilical artery was modeled as a fiber reinforced hyperelastic material in both control and PE conditions.

RESULTS

The PE arteries were stiffer than control arteries at stresses of 20-160 mmHg in the axial direction and 65-200 mmHg in the circumferential direction (P<0.05). The PE umbilical arteries exhibited a 58% and 48% increase in circumferential moduli at the systolic and diastolic blood pressure respectively compared to the controls (P<0.05). A hyperelastic model showed a substantial increase in both isotropic and anisotropic contribution in the mechanical behavior. Collectively, the changes observed correlated to a higher collagen fiber density in the PE group with increased hyperelastic material parameters (P<0.05).

CONCLUSION

PE umbilical arteries demonstrated stiffer biomechanics compared to the controls due to the change in collagen fiber content. These altered biomechanical and structural changes provide a potential snapshot into systemic vasculature remodeling occurring in the newborn.

Small artery elasticity predicts future cardiovascular events in chinese patients with angiographic coronary artery disease

Arterial elasticity has been shown to predict cardiovascular disease (CVD) in apparently healthy populations. The present study aimed to explore whether arterial elasticity could predict CVD events in Chinese patients with angiographic coronary artery disease (CAD). Arterial elasticity of 365 patients with angiographic CAD was measured. During follow-up (48 months; range 6-65), 140 CVD events occurred (including 34 deaths). Univariate Cox analysis demonstrated that both large arterial elasticity and small arterial elasticity were significant predictors of CVD events. Multivariate Cox analysis indicated that small arterial elasticity remained significant. Kaplan-Meier analysis showed that the probability of having a CVD event/CVD death increased with a decrease of small arterial elasticity (P < .001, respectively). Decreased small arterial elasticity independently predicts the risk of CVD events in Chinese patients with angiographic CAD.

Increased arterial stiffness and extracellular matrix reorganization in intrauterine growth-restricted fetal sheep

BACKGROUND

Fetal intrauterine growth restriction (IUGR) results in increased placental resistance to blood flow, fetal hypertension, and increased pulsatility stresses shown to lead to vascular remodeling. We tested our hypothesis that IUGR causes decreased compliance in the carotid and umbilical arteries due to altered extracellular matrix (ECM) composition and structure.

METHODS

A sheep model of placental insufficiency-induced IUGR (PI-IUGR) was created by exposure of the pregnant ewe to elevated ambient temperatures. Umbilical and carotid arteries from near-term fetuses were tested with pressure-diameter measurements to compare passive compliance in control and PI-IUGR tissues. ECM composition was measured via biochemical assay, and the organization was determined by using histology and second-harmonic generation imaging.

RESULTS

We found that PI-IUGR increased arterial stiffness with increased collagen engagement, or transition stretch. PI-IUGR carotid arteries exhibited increased collagen and elastin quantity, and PI-IUGR umbilical arteries exhibited increased sulfated glycosaminoglycans. Histomorphology showed altered collagen-to-elastin ratios with altered cellular proliferation. Increased stiffness indicates altered collagen-to-elastin ratios with less elastin contribution leading to increased collagen engagement.

CONCLUSION

Because vessel stiffness is a significant predictor in the development of hypertension, disrupted ECM deposition in IUGR provides a potential link between IUGR and adult hypertension.

Hyperelastic remodeling in the intrauterine growth restricted (IUGR) carotid artery in the near-term fetus

A constitutive model for a fiber reinforced hyperelastic material was applied to understand arterial fiber remodeling in a sheep model of Intrauterine Growth Restriction (IUGR). IUGR is associated altered hemodynamics characterized by increased resistance to blood flow in the placenta and elevated fetal arterial pressure and pulsatility. The constitutive model describes the collagen contribution to the mechanics within the arterial wall in both control and IUGR carotid artery through defining the material modulus and the orientation of the microstructure. A sheep model of placental insufficiency induced IUGR (PI-IUGR) was created by exposure of the pregnant ewe to elevated ambient temperatures. Experimental data was collected using pressure-diameter measurements to measure passive compliance in control and PI-IUGR carotid arteries. The constitutive model was optimized to fit the experimental data predicting the material parameters. Specifically, the collagen fiber predicted angle (γ) in the control artery was 49.9° from the circumferential axis while the PI-IUGR was 16.6° with a 23.5% increase in fiber orientation (κ). Quantitative assessment of collagen fiber orientation in secondary harmonic generation images confirmed the shift in orientation between the two groups. Together these suggest vascular remodeling of the ECM fiber orientation plays a major role in arterial stiffening in the PI-IUGR near-term fetal sheep.

Relationship between carotid artery mechanics and the spontaneous baroreflex: a noninvasive investigation in normal humans

OBJECTIVES

This study addressed the relationship between spontaneous baroreflex sensitivity and carotid mechanical properties in a clinical setting.

METHODS

In 191 normal volunteers (age range 20-60 years, mean 44 ± 13), spontaneous indices of baroreflex regulation were obtained noninvasively in the time (baroreflex slope, BRS) and frequency domains (α index and systolic arterial pressure-RR interval transfer gain) as well as using an exogenous autoregressive causal model (A.XAR); carotid mechanical properties were estimated by ultrasound. The link between mechanical measures and spontaneous baroreflex indices was explored by multivariate analysis and linear modeling.

RESULTS

Participants were divided into five groups according to age decades. With advancing age we observed a decrease in spontaneous baroreflex indices (BRS from 31.2 to 16.3; α index from 27.4 to 13.6; RR-SAP gain at high frequency from 31 ± 3.0 to 14 ± 3.0 ms/mmHg all P < 0.001) and increase in carotid intima-media thickness (IMT: from 0.53 to 0.69 mm; P < 0.001) and stiffness (local wave speed: from 4.0 to 6.9 m/s; both P < 0.001). A significant correlation was found between spontaneous indices of baroreflex sensitivity and carotid mechanical properties, particularly wave speed (r = -0.328, P < 0.001). After adjusting for age and sex, a significant correlation remained between RR-SAP gain and wave speed and between A.XAR and IMT. Factor analysis and automatic linear modeling confirmed the observation that mechanical carotid properties are strong predictors of the age-related reduction of spontaneous baroreflex.

CONCLUSION

A significant correlation between spontaneous baroreflex indices and local carotid mechanical properties supports the idea that they should be considered in the physiology of baroreflex regulation.

Carotid intima-media thickness is increased in Turner syndrome: multifactorial pathogenesis depending on age, blood pressure, cholesterol and oestrogen treatment

OBJECTIVE

Carotid intima-media thickness (IMT) may potentially supplement cardiovascular risk assessment in Turner syndrome (TS), where cardiovascular risk is high and appropriate risk stratification difficult. Knowledge of IMT in TS is scarce, and this study aimed to enhance insight into the cardiovascular risk marker.

DESIGN, PATIENTS AND MEASUREMENTS

IMT was cross-sectionally assessed by ultrasonography of the common carotid artery (cIMT) and carotid bulb (bIMT) in TS (n = 69, age 40 ± 10 years) and age-matched, healthy female controls (n = 67). Additional prospective IMT assessment was performed in TS over 2·4 ± 0·3 years. Metabolic biomarkers and 24-h ambulatory blood pressure were also assessed.

RESULTS

cIMT and bIMT (body surface area indexed) were increased in TS (P < 0·05) with 17-18% having IMTs that exceeded the 95th percentile of the controls (P < 0·05). Blood pressure, heart rate, glycosylated haemoglobin A1c and high-density lipoprotein cholesterol were increased in TS, where 43% received antihypertensive treatment. cIMT decreased during follow-up, coinciding with intensified cardiovascular risk prophylaxis, whereas bIMT was unchanged. In multiple regression analyses (R = 0·52-0·69, P < 0·05), baseline IMT in TS increased with age, blood pressure and cholesterol as well as in the presence of diabetes whilst IMT was inversely associated with duration of oestrogen replacement. In an analogue analysis, the prospective changes in cIMT (R = 0·37, P < 0·05) were beneficially influenced by antihypertensive treatment and oestrogen therapy and adversely by the presence of diabetes.

CONCLUSION

Carotid IMT was abnormal in TS and negatively influenced by age, metabolic biomarkers, blood pressure and short duration of oestrogen treatment. Attention to common cardiovascular and endocrine risk markers over more than 2 years appeared to influence IMT beneficially.

The EPICure study: association between hemodynamics and lung function at 11 years after extremely preterm birth

OBJECTIVE

To investigate the relationship between disturbed lung function and large-artery hemodynamics in school-age children born extremely preterm (EP) (at 25 completed weeks of gestation or less).

STUDY DESIGN

This was a cross-sectional study of participants from the EPICure study, now aged 11 years (n = 66), and 86 age- and sex-matched term-born classmates. Spirometry parameters (including forced expiratory volume in 1 second), blood pressure, and augmentation index (AIx, a composite of arterial stiffness and global wave reflections) were measured.

RESULTS

Compared with their classmates, the EP children had significantly impaired lung function, particularly those with neonatal bronchopulmonary dysplasia. Peripheral blood pressure did not differ significantly between the 2 groups, but AIx values were on average 5% higher (95% CI, 2%-8%) in the preterm infants, remaining significant after adjustment for potential confounders. Neonatal bronchopulmonary dysplasia status was not related to AIx. Lung function and maternal smoking were independently associated with AIx; AIx increased by 2.7% per z-score reduction in baseline forced expiratory volume in 1 second and by 4.9% in those whose mothers smoked during pregnancy.

CONCLUSION

The independent association between impaired lung function and cardiovascular physiology in early adolescence implies higher cardiovascular risk for children born EP, and suggests that prevention of chronic neonatal lung disease may be a priority in reducing later cardiovascular risk in preterm infants.

Cardiovascular phenotype in Turner syndrome--integrating cardiology, genetics, and endocrinology

Cardiovascular disease is emerging as a cardinal trait of Turner syndrome, being responsible for half of the 3-fold excess mortality. Turner syndrome has been proposed as an independent risk marker for cardiovascular disease that manifests as congenital heart disease, aortic dilation and dissection, valvular heart disease, hypertension, thromboembolism, myocardial infarction, and stroke. Risk stratification is unfortunately not straightforward because risk markers derived from the general population inadequately identify the subset of females with Turner syndrome who will suffer events. A high prevalence of endocrine disorders adds to the complexity, exacerbating cardiovascular prognosis. Mounting knowledge about the prevalence and interplay of cardiovascular and endocrine disease in Turner syndrome is paralleled by improved understanding of the genetics of the X-chromosome in both normal health and disease. At present in Turner syndrome, this is most advanced for the SHOX gene, which partly explains the growth deficit. This review provides an up-to-date condensation of current state-of-the-art knowledge in Turner syndrome, the main focus being cardiovascular morbidity and mortality. The aim is to provide insight into pathogenesis of Turner syndrome with perspectives to advances in the understanding of genetics of the X-chromosome. The review also incorporates important endocrine features, in order to comprehensively explain the cardiovascular phenotype and to highlight how raised attention to endocrinology and genetics is important in the identification and modification of cardiovascular risk.

Can ambulatory blood pressure measurements substitute assessment of subclinical cardiovascular damage?

OBJECTIVE

We have previously demonstrated that markers of subclinical organ damage (SOD) improve cardiovascular risk prediction in healthy individuals. We wanted to investigate whether this additive effect of SOD was due to inaccurate blood pressure (BP) measurement or whether ambulatory BP (AMBP) added further to risk prediction.

METHODS

In a population cohort of 1385 Danish individuals free of cardiovascular disease and diabetes, we recorded traditional risk factors, AMBP and pulse wave velocity (PWV), urine albumin/creatinine ratio (UACR), left ventricular mass index (LVMI) and carotid atherosclerotic plaques at baseline. A composite cardiovascular endpoint (CEP) consisting of cardiovascular death and nonfatal myocardial infarction and stroke was recorded in national registries.

RESULTS

During a median follow-up of 12.8 years, a total of 119 CEPs occurred. In categorical analysis, presence of SOD as well as masked hypertension increased sensitivity of Systemic Coronary Risk Estimation from 73.9 to 89.1% (P < 0.001) and reduced specificity from 60.1 to 41.8% (P < 0.001). In continuous analysis, logUACR [hazard ratio = 1.20 (95% confidence interval [CI] 1.05-1.38), P = 0.009], atherosclerotic plaques [hazard ratio = 1.82 (95% CI 1.21-2.74), P = 0.004] and 24-h SBP [hazard ratio = 1.34 (95% CI 1.12-1.60), P = 0.002] but not logPWV or LVMI predicted CEP in a model with adjustments for age, sex, conventional BP, total cholesterol and smoking. Compared with a risk model using only traditional risk factors, adding PWV, UACR, plaques, LVMI and 24-h SBP increased C-index significantly from 0.76 to 0.79% and produced a net reclassification improvement of 23.3% (P = 0.001).

CONCLUSION

UACR and plaques predicted cardiovascular events independently of AMBP and improved risk prediction.

Bringing prevention in geriatrics: evidences from cardiovascular medicine supporting the new challenge

Aging is a dynamic and systemic process, with high inter-individual heterogeneity, likely partially adaptive. Cardiovascular disease and hypertension are among the leading conditions causing disabilities in older subjects. If, in accordance with most recent definition, prevention is any intervention before the patient receives a diagnosis, prevention is possible at any age. Additionally, disability and CV disease in the elderly may be prevented by targeting factors underlying and modulating the arterial aging process. Cross-talk between arterial and brain aging will be discussed in this context as a paradigmatic clinical model fostering prevention in older subjects.

Prognostic value of the variability in home-measured blood pressure and heart rate: the Finn-Home Study

The objective of the study was to assess the prognostic value of variability in home-measured blood pressure (BP) and heart rate (HR) in a general population. We studied a representative sample of the Finnish adult population with 1866 study subjects aged 45-74 years. BP and HR self-measurements were performed on 7 consecutive days. The variabilities of BP and HR were defined as the SDs of morning minus evening, day-by-day, and first minus second measurements. The primary end point was incidence of a cardiovascular event. The secondary end point was total mortality. During a follow-up of 7.8 years, 179 subjects had experienced a cardiovascular event, and 130 subjects had died. In Cox proportional hazard models adjusted for age, sex, BP/HR, and other cardiovascular risk factors, morning-evening home BP variability (systolic/diastolic relative hazard: 1.04/1.10 [95% CI: 1.01-1.07/1.05-1.15] per 1-mm Hg increase in BP variability) and morning day-by-day home BP variability (relative hazard: 1.04/1.10 [95% CI: 1.00-1.07/1.04-1.16] per 1-mm Hg increase in BP variability) were predictive of cardiovascular events. Morning-evening home HR variability (relative hazard: 1.07 [95% CI: 1.02-1.12] per 1-bpm increase in HR variability) and morning day-by-day home HR variability (relative hazard: 1.11 [95% CI: 1.05-1.17] per 1-bpm increase in HR variability) were also independent predictors of cardiovascular events. Greater variabilities of morning home BP and HR are independent predictors of cardiovascular events. Because the variabilities of home BP and HR are easily acquired in conjunction with home BP and HR level, they should be used as the additive information in the assessment of cardiovascular risk.

Cardiovascular consequences of extreme prematurity: the EPICure study

OBJECTIVES

The long-term consequences of extreme prematurity are becoming increasingly important, given recent improvements in neonatal intensive care. The aim of the current study was to examine the cardiovascular consequences of extreme prematurity in 11-year-olds born at or before 25 completed weeks of gestation.

METHODS

Age and sex-matched classmates were recruited as controls. Information concerning perinatal and maternal history was collected, and current anthropometric characteristics were measured in 219 children born extremely preterm and 153 classmates. A subset of the extremely preterm children (n = 68) and classmates (n = 90) then underwent detailed haemodynamic investigations, including measurement of supine blood pressure (BP), aortic pulse wave velocity (aPWV, a measure of aortic stiffness) and augmentation index (AIx, a measure of arterial pressure wave reflections).

RESULTS

Seated brachial systolic and diastolic BP were not different between extremely preterm children and classmates (P = 0.3 for both), although there was a small, significant elevation in supine mean and diastolic BP in the extremely preterm children (P < 0.05 for both). Arterial pressure wave reflections were significantly elevated in the extremely preterm children (P < 0.001) and this persisted after adjusting for confounding variables. However, aortic stiffness was not different between the groups (P = 0.1).

CONCLUSIONS

These data suggest that extreme prematurity is associated with altered arterial haemodynamics in children, not evident from the examination of brachial BP alone. Moreover, the smaller, preresistance and resistance vessels rather than large elastic arteries appear to be most affected. Children born extremely preterm may be at increased future cardiovascular risk.

Telomerase expression on aortic wall endothelial cells is attenuated in abdominal aortic aneurysms compared to healthy nonaneurysmal aortas

OBJECTIVE

Linear chromosomes carry specific DNA structures at their ends called telomeres. The latter shorten with each successive cell division making their length a marker of cell age. Telomerase prevents such telomere attrition by adding back telomeric repeats at the telomere ends, thus playing an important role in cell aging. On the other hand, an abdominal aortic aneurysm (AAA) represents an age-related degenerative disorder. The aim of the present study was to investigate a potential correlation of telomerase expression with AAA formation.

METHODS

Aortic wall tissue samples were collected from 49 patients (mean age, 63.8 ± 4.4 years) with AAAs during open elective repair and from 24 deceased organ donors as controls (mean age, 60.5 ± 3.9 years). Telomerase expression on endothelial cells was detected by immunohistochemistry. Associations of telomerase positivity with AAAs and epidemiologic and clinical variables were investigated.

RESULTS

Telomerase expression was significantly decreased in patients with AAAs (11 of 49; 22.4%) compared to controls (19 of 24; 79.2%; P < .001). This association persisted after adjustment for age, gender, coronary artery disease (CAD), hypercholesterolemia, hypertension and smoking (odds ratio, 0.47; 95% confidence interval, 0.14-0.58; P < .01.).

CONCLUSION

Patients with AAAs have attenuated telomerase endothelial expression compared to controls, implying a protective role of telomerase against AAA formation. Further investigation of pathways involved in vascular aging may contribute to elucidation of AAA pathogenetic mechanisms.

Vascular contributions to cognitive impairment and dementia: a statement for healthcare professionals from the american heart association/american stroke association

BACKGROUND AND PURPOSE

This scientific statement provides an overview of the evidence on vascular contributions to cognitive impairment and dementia. Vascular contributions to cognitive impairment and dementia of later life are common. Definitions of vascular cognitive impairment (VCI), neuropathology, basic science and pathophysiological aspects, role of neuroimaging and vascular and other associated risk factors, and potential opportunities for prevention and treatment are reviewed. This statement serves as an overall guide for practitioners to gain a better understanding of VCI and dementia, prevention, and treatment.

METHODS

Writing group members were nominated by the writing group co-chairs on the basis of their previous work in relevant topic areas and were approved by the American Heart Association Stroke Council Scientific Statement Oversight Committee, the Council on Epidemiology and Prevention, and the Manuscript Oversight Committee. The writing group used systematic literature reviews (primarily covering publications from 1990 to May 1, 2010), previously published guidelines, personal files, and expert opinion to summarize existing evidence, indicate gaps in current knowledge, and, when appropriate, formulate recommendations using standard American Heart Association criteria. All members of the writing group had the opportunity to comment on the recommendations and approved the final version of this document. After peer review by the American Heart Association, as well as review by the Stroke Council leadership, Council on Epidemiology and Prevention Council, and Scientific Statements Oversight Committee, the statement was approved by the American Heart Association Science Advisory and Coordinating Committee.

RESULTS

The construct of VCI has been introduced to capture the entire spectrum of cognitive disorders associated with all forms of cerebral vascular brain injury-not solely stroke-ranging from mild cognitive impairment through fully developed dementia. Dysfunction of the neurovascular unit and mechanisms regulating cerebral blood flow are likely to be important components of the pathophysiological processes underlying VCI. Cerebral amyloid angiopathy is emerging as an important marker of risk for Alzheimer disease, microinfarction, microhemorrhage and macrohemorrhage of the brain, and VCI. The neuropathology of cognitive impairment in later life is often a mixture of Alzheimer disease and microvascular brain damage, which may overlap and synergize to heighten the risk of cognitive impairment. In this regard, magnetic resonance imaging and other neuroimaging techniques play an important role in the definition and detection of VCI and provide evidence that subcortical forms of VCI with white matter hyperintensities and small deep infarcts are common. In many cases, risk markers for VCI are the same as traditional risk factors for stroke. These risks may include but are not limited to atrial fibrillation, hypertension, diabetes mellitus, and hypercholesterolemia. Furthermore, these same vascular risk factors may be risk markers for Alzheimer disease. Carotid intimal-medial thickness and arterial stiffness are emerging as markers of arterial aging and may serve as risk markers for VCI. Currently, no specific treatments for VCI have been approved by the US Food and Drug Administration. However, detection and control of the traditional risk factors for stroke and cardiovascular disease may be effective in the prevention of VCI, even in older people.

CONCLUSIONS

Vascular contributions to cognitive impairment and dementia are important. Understanding of VCI has evolved substantially in recent years, based on preclinical, neuropathologic, neuroimaging, physiological, and epidemiological studies. Transdisciplinary, translational, and transactional approaches are recommended to further our understanding of this entity and to better characterize its neuropsychological profile. There is a need for prospective, quantitative, clinical-pathological-neuroimaging studies to improve knowledge of the pathological basis of neuroimaging change and the complex interplay between vascular and Alzheimer disease pathologies in the evolution of clinical VCI and Alzheimer disease. Long-term vascular risk marker interventional studies beginning as early as midlife may be required to prevent or postpone the onset of VCI and Alzheimer disease. Studies of intensive reduction of vascular risk factors in high-risk groups are another important avenue of research.

Arterial stiffness and 24 h ambulatory blood pressure monitoring in young healthy volunteers: the early vascular ageing Aristotle University Thessaloniki Study (EVA-ARIS Study)

Differences in 24 h blood pressure (BP) monitoring parameters such as average 24 h BP, day to night BP ratio and BP variability could have an impact in arterial stiffness. The study hypothesis was that despite similar average BP values in ambulatory blood pressure monitoring subjects with increased 24 h BP variability may have increased arterial stiffness. The study population consisted of 115 consecutive young healthy volunteers. Carotid-femoral PWV was measured in all subjects. Clinic BP was measured and an appropriate cuff was fitted on the non-dominant arm of each subject for a 24 h ambulatory blood pressure monitoring session. Waist to hip ratio as well as BMI was measured. Family history and smoking habits were recorded. In univariate analysis, estimated carotid-femoral PWV showed a significant correlation with age, weight, waist circumference, height, clinic systolic and diastolic BP, 24-h systolic and diastolic BP, 24-h pulse pressure, 24-h systolic and diastolic BP variability, daytime systolic and diastolic BP, daytime pulse pressure, daytime systolic and diastolic BP variability, nighttime systolic BP, nighttime pulse pressure and nighttime systolic BP variability. In multivariate regression analysis, age (B=0.95, P<0.001) and 24 h systolic BP variability (B=0.28, P<0.001) were independent determinanats of arterial stiffness. In conclusions, increased 24 h systolic BP variability is associated with arterial stiffness in young healthy volunteers. Pulse wave velocity in a young healthy population is useful to identify determinants of premature arterial stiffness, thus further elucidating the aspects of early vascular ageing.

Angiotensin II and the vascular phenotype in hypertension

Hypertension is associated with vascular changes characterised by remodelling, endothelial dysfunction and hyperreactivity. Cellular processes underlying these perturbations include altered vascular smooth muscle cell growth and apoptosis, fibrosis, hypercontractility and calcification. Inflammation, associated with macrophage infiltration and increased expression of redox-sensitive pro-inflammatory genes, also contributes to vascular remodelling. Many of these features occur with ageing, and the vascular phenotype in hypertension is considered a phenomenon of ‘premature vascular ageing’. Among the many factors involved in the hypertensive vascular phenotype, angiotensin II (Ang II) is especially important. Ang II, previously thought to be the sole effector of the renin–angiotensin system (RAS), is converted to smaller peptides [Ang III, Ang IV, Ang-(1-7)] that are biologically active in the vascular system. Another new component of the RAS is the (pro)renin receptor, which signals through Ang-II-independent mechanisms and might influence vascular function. Ang II mediates effects through complex signalling pathways on binding to its G-protein-coupled receptors (GPCRs) AT1R and AT2R. These receptors are regulated by the GPCR-interacting proteins ATRAP, ARAP1 and ATIP. AT1R activation induces effects through the phospholipase C pathway, mitogen-activated protein kinases, tyrosine kinases/phosphatases, RhoA/Rhokinase and NAD(P)H-oxidase-derived reactive oxygen species. Here we focus on recent developments and new research trends related to Ang II and the RAS and involvement in the hypertensive vascular phenotype.

Is vascular stiffness a target for therapy?

BACKGROUND

Early cardiovascular disease starts in the endothelium leading to functional changes in the vasculature. These changes can be depicted by assessment of arterial stiffness or elasticity. There are several techniques to assess arterial stiffness. Increased arterial stiffness or decreased arterial elasticity has been associated with cardiovascular risk factors. There is now evidence that small artery elasticity is a strong predictor for arterial hypertension. Moreover arterial elasticity provides extra prognostic information beyond arterial blood pressure measurement. Arterial stiffness attenuation may reflect the true reduction of arterial wall damage.

RESULTS

ACE-inhibitors, angiotensin II receptor blockers, aldosterone antagonists and calcium antagonists have favorable effects in improving arterial elasticity, while beta-blockers have an inverse effect. Diuretics have not been evaluated. Lipid lowering therapy, some antidiabetic therapy have shown to reduce arterial stiffness. Inflammatory and infectious diseases have been associated with vascular inflammation and consequently increase in arterial stiffness. The effect of anti-inflammatory agents and antiretroviral therapy on arterial stiffness is under investigation.

CONCLUSIONS

Measurement of arterial stiffness will not only be helpful in the detection of early vascular disease but also as a tool in the selection and follow-up monitoring of therapeutic strategies aimed at preventing or delaying progression of vascular disease.

High blood pressure in children: clinical and health policy implications

Hypertension is a global problem, affecting both developed and developing nations. In addition to being a major cause of morbidity and mortality, hypertension places a heavy burden on health care systems, families, and society as a whole. Despite evidence of an increasing prevalence of hypertension among youth, the consequences of early onset are poorly established and often overlooked. Childhood hypertension is often asymptomatic and easily missed, even by health professionals. Target organ damage is detectable in children and adolescents, however, and hypertension continues into adulthood. Additional strategies to improve cardiovascular health among children and adolescents are needed, including methods to achieve healthy lifestyles at home and in school, improved systems for diagnosis, and research on mechanisms and timing of interventions. The burden of hypertension in the young will continue to grow unless it is given the attention it deserves by policy makers, health care providers, schools, parents, and society. This report aims to increase awareness of the problem of hypertension in childhood. Recent reports on prevalence and target organ injury are discussed and health policy initiatives to improve blood pressure control are proposed.

Early vascular phenotypes in the genesis of hypertension

Cardiovascular complications occurring in adults find their roots in risk factors operating early in life. Among the factors influencing cardiovascular risk, blood pressure values in children represent an important measurable marker of the level of potential cardiovascular risk later in life because the levels are both the cause and the consequence of early vascular alterations. Early vascular phenotypes represent a field of great interest, and they can be studied through indirect assessment using non-invasive techniques. Estimations of blood pressure components, pulse wave velocity, and reflecting waves provide valuable information that can be easily recorded and repeated overtime. A direct assessment, carried out by examining the umbilical vessels, can add further valuable information. In this review, we discuss the potential application of surrogate markers of early vascular alterations and describe the information provided by umbilical cord vessels.

Evaluating arterial aging in the clinical setting: a tentative agenda for critical appraisal

Population aging is a worldwide phenomenon. However, the cultural attitude to older adults has not yet incorporated understanding of the effects of the aging process. The arterial system is affected by the aging process, which is responsible for the great majority of mortality, morbidity and disability in older people. We briefly describe how the aging process affects large arteries and their properties that are easily measurable noninvasively, and suggest a tentative agenda for solving the critical problems that have hampered the diffusion of routine assessment of arterial aging in the clinical setting.

Stopping the cardiovascular disease continuum: Focus on prevention

The cardiovascular disease continuum (CVDC) is a sequence of events, which begins from a host of cardiovascular risk factors that consists of diabetes mellitus, dyslipidemia, hypertension, smoking and visceral obesity. If it is not intervened with early, it inexorably progresses to atherosclerosis, coronary artery disease, myocardial infarction, left ventricular hypertrophy, and left ventricular dilatation, which lead to left ventricular diastolic or systolic dysfunction and eventually end-stage heart failure and death. Treatment intervention at any stage during its course will either arrest or delay its progress. In this editorial, the cardiovascular risk factors that initiate and perpetuate the CVDC are briefly discussed, with an emphasis on their early prevention or aggressive treatment.

Maternal alcohol intake and offspring pulse wave velocity

BACKGROUND

Intrauterine exposure to alcohol may affect cardiovascular development, increasing risk of cardiovascular malformations. Intrauterine exposure to light maternal alcohol intake has been reported to affect human umbilical arterial contractility, and adult sheep exposed in utero have had altered cerebrovascular reactivity. In human adults, alcohol intake affects arterial stiffness.

OBJECTIVES

We investigated whether intrauterine exposure to alcohol was associated with childhood pulse wave velocity (PWV), a measure of arterial stiffness.

METHODS

On postnatal day 4, mothers of 147 twin pairs born in Tasmania from 1991 to 1993 reported alcohol intake during each trimester of pregnancy. At 9 years, child PWV was assessed over carotid-femoral and femoral-dorsalis pedis arterial segments by applanation tonometry.

RESULTS

Carotid-femoral PWV was 0.2 m/s (95% CI 0.06, 0.4) higher (indicating stiffer vessels) in children whose mothers drank alcohol in the 2nd trimester rather than abstained, after adjusting for potential confounding factors. A similar effect was not seen for femoral-dorsalis pedis PWV. Findings were independent of child blood pressure which correlated strongly with PWV. Alcohol intake varied little between trimesters, so it was not possible to assess the effect of timing of exposure.

CONCLUSIONS

Carotid-femoral PWV in adults is predictive of cardiovascular morbidity and mortality. The degree of continuity between childhood and adulthood PWV is unknown, but as we found an association between prenatal alcohol exposure and carotid-femoral PWV at 9 years, a permanent change in vessel wall structure or function is possible. These findings need to be confirmed in other and larger cohorts, and mechanistic animal studies are needed.

The central arterial burden of the metabolic syndrome is similar in men and women: the SardiNIA Study

AIMS

We evaluated whether specific clusters of metabolic syndrome (MetS) components differentially impact on arterial structure and function, and whether the impact is similar in men and in women.

METHODS AND RESULTS

Components of the MetS and arterial properties were assessed in 6148 subjects, aged 14-102 in a cluster of four towns in Sardinia, Italy. MetS was defined in accordance with the ATP III criteria. Age groups were classified as: <35, 35-49, 50-64, and > or =65 years. Systolic blood pressure (BP), diastolic BP, pulse pressure, common carotid artery (CCA) diameter, intima-media thickness, distensibility, strain, stiffness index, wall stress, and aortic pulse wave velocity were measured. Common carotid artery plaque was defined as focal encroachment of the arterial wall and CCA calcification as acoustic shadowing. In any age group, subjects with MetS presented thicker, stiffer or less distensible, and wider large arteries than controls. The arterial burden of MetS increased as the number of altered MetS components increased. However, not all MetS components were associated with the same changes in arterial properties. In fact, specific clusters of MetS components, i.e. any combination of altered glucose tolerance, elevated BP, and elevated triglycerides (with or without abdominal obesity), dramatically increased age-associated arterial changes. The impact of MetS on arterial function was similar in men and women.

CONCLUSION

MetS accelerates age-associated arterial changes, even in older persons. However, not all the clusters of MetS components render the same burden on arterial structure and function.

Mechanisms of hypertension in the cardiometabolic syndrome

Arterial hypertension is often part of a constellation of anthropometric and metabolic abnormalities that occur simultaneously to a higher degree than would be expected by chance alone, supporting the existence of a discrete disorder, the so-called metabolic syndrome. It is the result of interactions among a large number of interconnected mechanisms, which eventually lead to both an increase in cardiovascular and renal risk, and the development of diabetes. Mechanisms involved in the metabolic syndrome are obesity, insulin resistance, and a constellation of independent factors, which include molecules of hepatic, vascular, and immunologic origin with pro-inflammatory properties. At each of these key points are interactions of demographics, lifestyle, genetic factors, and environmental fetal programming. Superimposing upon these are infections or chronic exposure or both to certain drugs that can also make their contribution. Skeletal muscle and the liver, not adipose tissue, are the two key insulin-response tissues involved in maintaining glucose balance, although abnormal insulin action in the adipocytes also plays a role in development of the syndrome. Factors commonly associated with and partly dependent on obesity, insulin resistance, such as overactivity of the sympathetic, stimulation of the renin-angiotensin-aldosterone systems, abnormal renal sodium handling, endothelial dysfunction, and large vessels' alterations, may play a key role in the blood pressure elevation of the syndrome.

Influence of concurrent obesity and low birth weight on blood pressure phenotype in youth

The aim of this study was to assess the impact of obesity and low birth weight on both office and ambulatory blood pressure (BP) values, as well as on aortic-derived parameters in youths. A total of 422 white youths, from 10 to 18 years of age, were included. Subjects were divided into 4 groups according to the presence (234; 55%) or the absence (188; 45%) of obesity and according to low (114; 27%) or normal (308; 73%, birth weight. Spacelabs 90207 was used to measure ambulatory BP during a 24-hour period. SphygmoCor radial/aortic transform software was used to estimate aortic pressure waveform. Office, 24-hour, daytime, and nighttime systolic BP values were significantly higher in those subjects with low birth weight who became obese. The lowest BP values were present in nonobese subjects in the absence of low birth weight. In the middle, with similar BP values, were nonobese subjects with low birth weight and obese subjects in the absence of low birth weight. No interaction existed between obesity and low birth weight in the office (P=0.165) or ambulatory (P=0.603) systolic BP values. Augmentation index, an estimate of the pulse wave reflection, was significantly higher in the nonobese low birth weight group when compared with the other groups after controlling for height, heart rate, and diastolic BP. A significant interaction between low birth weight and obesity (P<0.005) existed. In conclusion, although the low birth weight children who become obese have the highest systolic BP values, the presence of obesity blunts the increment of the reflecting wave observed in low birth weight subjects.