Gender differences of aortic wave reflection and influence of menopause on central blood pressure in patients with arterial hypertension

Background

Evidences suggest that central hemodynamics indexes are independent predictors of future cardiovascular events and all-cause mortality. Multiple factors have been pointed to have potential influence on central aortic function: height, heart rate, left ventricular ejection duration and blood pressure level. Data related to the influence of gender and postmenopausal status on aortic waveform reflection is scarce. We aim to evaluate the impact of gender and menopause on central blood pressure of hypertensive patients.

Methods

In a cross sectional study 122 hypertensive patients (52 men and 70 women) were studied. Hypertension was defined as blood pressure (BP) levels ≥140/90 mmHg or use of antihypertensive drugs. Central arterial pressure, augmentation index (AIx) and augmentation index normalized to 75 bpm (AIx75) were obtained using applanation tonometry. Menopause and postmenopause history were accessed by a direct series of questions. Postmenopause was defined as at least one year since last menstruation. Patients were paired by age, gender and menopausal status, and the data were compared considering gender and menopausal status.

Results

Height and weight were significantly lower in women than in men at the same age. Conversely, AIx (32.7 ± 9.8% vs. 20.1 ± 11.7%, p < 0.01), AIx75 (29.6 ± 6.7% vs. 18.3 ± 9.4%, p < 0.01) and central systolic blood pressure (136 ± 30 vs. 125 ± 23 mmHg, p = 0.03) were higher in women than men. The menopausal women (mean age of menopause = 48 years) had the worst indexes of aortic wave reflection, compared to men at the same age and younger women.

Conclusion

Hypertensive women had both higher reflected aortic pressure waveform and central blood pressure indexes than hypertensive men, and these findings were worsened by the menopausal status.

Prevalence of Metabolic Syndrome and Framingham Risk Score in Apparently Healthy Vegetarian and Omnivorous Men

BACKGROUND

Recent studies have shown a lower prevalence of metabolic syndrome (MSyn) in vegetarians (VEG) despite the inconclusive evidence from others.

OBJECTIVE

To verify the association between diet and other lifestyle characteristics and the prevalence of MSyn, cardiovascular risk factors (CRF), and Framingham Risk Score (FRS) in apparently healthy VEG and omnivorous (OMN) men.

METHODS

In this cross-sectional study, 88 apparently healthy men ≥ 35 years, 44 VEG and 44 OMN, were assessed for anthropometric data, blood pressure, blood lipids, glucose, C-reactive protein (CRP) and FRS. To test the association between lifestyle and MSyn, Student t test, chi-square test, and multiple logistic regression model were used. A significance level of 5% was considered in all statistical analyses.

RESULTS

Several CRF were significantly lower in VEG than in OMN: body mass index, systolic blood pressure, diastolic blood pressure, fasting serum total cholesterol, LDL-cholesterol, apolipoprotein b, glucose, and glycated hemoglobin (all p < 0.05). The FRS mean was lower in VEG than in OMN (2.98 ± 3.7 vs 4.82 ± 4.8, p = 0.029). The percentage of individuals with MSyn was higher among OMN than among VEG (52.3 vs.15.9%) (p < 0.001). The OMN diet was associated with MSyn (OR: 6.28 95%CI 2.11-18.71) and alterations in most MSyn components in the multiple regression model independently of caloric intake, age and physical activity.

CONCLUSION

The VEG diet was associated with lower CRF, FRS and percentage of individuals with MSyn.

There Is No Impact of Diabetes on the Endothelial Function of Chronic Kidney Disease Patients

BACKGROUND

Patients with chronic kidney disease (CKD) and type 2 diabetes mellitus (DM) have increased risk of endothelial dysfunction, cardiovascular disease, and mortality. Several studies have separately analyzed endothelial function in these populations. However, data of patients with both CKD and DM are scarce. The aim of this study was to evaluate whether the presence of DM has any additional effect on the endothelial dysfunction of CKD patients.

METHODS

We measured endothelial progenitor cells (EPCs), stromal-derived factor 1 alpha (SDF-1α), serum and urinary nitric oxide (NO), flow-mediated dilation (FMD), and pulse wave velocity (PWV) in 37 CKD patients with DM (CKD-DM group) and in 37 without DM (CKD group).

RESULTS

CKD-DM group had a higher prevalence of obesity (P < 0.01), previous myocardial infarction (P = 0.02), myocardial revascularization (P = 0.04), and a trend for more peripheral artery disease (P = 0.07). Additionally, CKD-DM group had higher EPC (P = 0.001) and PWV (P < 0.001) values. On the other hand, no difference in SDF-1α and serum or urinary NO and FMD was observed between the groups.

CONCLUSIONS

Endothelial dysfunction is frequent in CKD patients, and an additive effect of diabetes cannot be implicated, suggesting the predominant role of uremia in this condition.

Intermittent claudication and severe renal artery stenosis are independently associated in hypertensive patients referred for renal arteriography

OBJECTIVE:

The purpose of this study was to evaluate the association between the presence of clinical symptoms of peripheral artery disease and severe renal artery stenosis in patients referred for renal angiography.

METHOD:

We included 82 patients with clinical suspicion of renovascular hypertension and performed an imaging investigation (renal Doppler ultrasound and/or renal scintigraphy) for possible renal artery stenosis. All patients underwent renal arteriography and were examined for peripheral artery disease based on the presence of intermittent claudication and ankle-brachial index test results. Severe renal artery stenosis was defined as a lesion causing 70% obstruction.

RESULTS:

Severe renal artery stenosis was present in 32 of 82 (39%) patients. Patients with severe renal artery stenosis were older (63±12 vs 56±12 years, p=0.006), had more intermittent claudication (55 vs 45%, p=0.027), and had a greater prevalence of an ankle-brachial index <0.9 (44% vs 20%, p=0.021) than patients without severe renal artery stenosis. Multivariate logistic regression analysis showed that the presence of intermittent claudication was independently associated with renal artery stenosis ≥70% (OR: 3.33; 95% CI 1.03-10.82, p=0.04), unlike the ankle-brachial index, which showed no association (OR: 1.44; 95% CI 0.37-5.66, p=0.60).

CONCLUSION:

Intermittent claudication is independently associated with severe renal artery stenosis (≥70%) in patients clinically suspected of having renovascular hypertension.

Reduced subclinical carotid vascular disease and arterial stiffness in vegetarian men: The CARVOS Study

BACKGROUND

Dietary habits play an important role in the development of atherosclerosis, the most important cause of morbidity and mortality in the world. The objective of this study was to verify if vegetarian (VEG) diet could be related a better profile of subclinical vascular disease evaluated by arterial stiffness and functional and structural properties of carotid arteries, compared to omnivorous (OMN) diet.

METHODS

In this cross-sectional study, 44 VEG and 44 OMN apparently healthy men ≥35years of age, in order to not have confounding risk factors of subclinical atherosclerosis, were assessed for anthropometric data, blood pressure, blood lipids, glucose, C reactive protein (CRP), and arterial stiffness determined by carotid-femoral pulse wave velocity (PWV). Also, carotid intima-media thickness (c-IMT) and distensibility were evaluated.

RESULTS

VEG men had lower body mass index, systolic and diastolic blood pressures, fasting serum total cholesterol, LDL and non-HDL-cholesterol, apolipoprotein B, glucose and glycated hemoglobin values in comparison with OMN individuals (all p values <0.05). Markers of vascular structure and function were different between VEG and OMN: PWV 7.1±0.8m/s vs. 7.7±0.9m/s (p<0.001); c-IMT 593±94 vs. 661±128μm (p=0.003); and relative carotid distensibility 6.39±1.7 vs. 5.72±1.8% (p=0.042), respectively. After a multivariate linear regression analysis, a VEG diet was independently and negatively associated with PWV (p value 0.005).

CONCLUSIONS

A VEG diet is associated with a more favorable cardiovascular diseases biomarker profile and better vascular structural and functional parameters.

Neurovascular Control and Cardiac Structure in Amateur Runners with Hypertension

PURPOSE

The neurovascular mechanisms underlying hypertension are minimized by exercise training. However, it is not known whether previously trained individuals with hypertension would have deleterious repercussion of this disease. Our aim was to investigate the neurovascular control and the cardiac structure of athletes with hypertension.

METHODS

Muscle sympathetic nerve activity (MSNA) (microneurography), baroreflex sensitivity (intravenous infusion of phenylephrine and nitroprusside), arterial stiffness (pulse wave velocity and echotracking), and cardiac structure (echocardiography) were evaluated in 17 runners with hypertension (42 ± 1 yr) and 20 normotensive (43 ± 1 yr) amateur runners.

RESULTS

Runners with hypertension had higher MSNA (+24% burst frequency, P = 0.02; +24%, burst incidence, P < 0.01), left ventricular mass (+22%, P < 0.01), septum wall thickness (+9%, P = 0.04), posterior wall thickness (+11%, P = 0.04), and left atrium (+11%, P < 0.001) compared with normotensive runners. Baroreflex control of heart rate was lower in runners with hypertension during increase (P = 0.05) but not during decrease (P = 0.11) of systolic blood pressure when compared with normotensive runners. There was no difference between groups in baroreflex control of MSNA during increase (P = 0.38) and decrease (P = 0.36) of diastolic blood pressure. Pulse wave velocity (P = 0.71) and carotid variables: intima media thickness (P = 0.18), diameter (P = 0.09), and distension (P = 0.79) were similar between groups.

CONCLUSIONS

Sympathetic overactivity seems to be involved in the underlying mechanisms of hypertension in amateur runners. Alterations in cardiac structure and decreased baroreflex control of heart rate suggest limited protection from exercise training. However, baroreflex control of MSNA and elastic properties of artery are preserved in this population.

Glycemic control and arterial stiffness in a Brazilian rural population: Baependi Heart Study

BACKGROUND

Increased arterial stiffness predicts morbidity and mortality, independently of other cardiovascular risk factors, and glycemic control impairments are related to higher vascular stiffness. The aim of this study was to evaluate the association between HbA1c levels and increased arterial stiffness in a Brazilian rural population.

METHODS

For this study were selected 1675 individuals (both genders and aged over 18 years) resident in the municipality of Baependi, a city located in the Southeast of Brazil. HbA1c levels were determined by HPLC. Pulse wave velocity (PWV) was measured with a non-invasive automatic device (Complior).

RESULTS

HbA1c levels were associated with an increased PWV. This was more relevant for the third tertile of age. In addition, logistic regression multivariate model including age, blood pressure, gender, BMI and fasting glucose showed that the elevation of a single unit percentage of HbA1c represented an increase of 54 % in the odds of increased arterial stiffness [OR 1.54 (95 % CI 1.01-2.17)]. Both, HbA1c and fasting glucose showed higher discriminatory power in the risk assessment for increased arterial stiffness in the non-diabetic when compared to the diabetic group (AUC of HbA1c = 0.71 vs 0.57, p = 0.02; AUC of fasting glucose = 0.66 vs 0.45, p = 0.0007, respectively).

CONCLUSION

Our findings indicate that a increase in HbA1c levels is associated with increased arterial stiffness and that both, HbA1c and fasting glucose, presented higher discriminatory power in the risk assessment for increased arterial stiffness in the non-diabetic group as compared to diabetic individuals.

Determinants of Functional and Structural Properties of Large Arteries in Healthy Individuals

Background

Changes in the properties of large arteries correlate with higher cardiovascular risk. Recent guidelines have included the assessment of those properties to detect subclinical disease. Establishing reference values for the assessment methods as well as determinants of the arterial parameters and their correlations in healthy individuals is important to stratify patients.

Objective

To assess, in healthy adults, the distribution of the values of pulse wave velocity, diameter, intima-media thickness and relative distensibility of the carotid artery, in addition to assessing the demographic and clinical determinants of those parameters and their correlations.

Methods

This study evaluated 210 individuals (54% women; mean age, 44 ± 13 years) with no evidence of cardiovascular disease. The carotid-femoral pulse wave velocity was measured with a Complior^® device. The functional and structural properties of the carotid artery were assessed by using radiofrequency ultrasound.

Results

The means of the following parameters were: pulse wave velocity, 8.7 ± 1.5 m/s; diameter, 6,707.9 ± 861.6 μm; intima-media thickness, 601 ± 131 μm; relative distensibility, 5.3 ± 2.1%. No significant difference related to sex or ethnicity was observed. On multiple linear logistic regression, the factors independently related to the vascular parameters were: pulse wave velocity, to age (p < 0.01) and triglycerides (p = 0.02); intima-media thickness, to age (p < 0.01); diameter, to creatinine (p = 0.03) and age (p = 0.02); relative distensibility, to age (p < 0.01) and systolic and diastolic blood pressures (p = 0.02 and p = 0.01, respectively). Pulse wave velocity showed a positive correlation with intima media thickness (p < 0.01) and with relative distensibility (p < 0.01), while diameter showed a positive correlation with distensibility (p = 0.03).

Conclusion

In healthy individuals, age was the major factor related to aortic stiffness, while age and diastolic blood pressure related to the carotid functional measure. The carotid artery structure was directly related to aortic stiffness, which was inversely related to the carotid artery functional property.

Determinants of Arterial Stiffness in Female Patients with Takayasu Arteritis

Objective.

The assessment of pulse wave velocity (PWV) in Takayasu arteritis (TA) is complex because of many confounding factors. We evaluated PWV in female patients with TA and controls with comparable anthropometric and clinical variables and assessed a possible association of TA with disease variables.

Methods.

We evaluated 27 patients with TA consecutively. Exclusion criteria were menopause, smoking, diabetes, renal insufficiency, poorly controlled hypertension, cardiac arrhythmias, obesity, inflammatory comorbidities, pregnancy, and surgical procedures involving the aorta. Disease activity was determined by clinical and laboratory variables. As healthy controls, 27 subjects with comparable age, blood pressure, height, and weight were selected. Carotid-femoral PWV measurements were obtained using the Complior system.

Results.

The mean PWV in patients with TA was higher than in healthy controls (9.77 ± 3.49 vs 7.83 ± 1.06 m/s; p = 0.009). Despite our strict selection criteria, patients with TA had an average systolic blood pressure (SBP) 8 mmHg higher than controls (p = NS), and significantly higher pulse pressure values. The multivariate linear regression model shows that 93.8% of the PWV variability is explained by the variables age, mean BP, and the disease itself (adjusted R2= 0.938). Stepwise logistic analysis using the PWV cutoff value established by the receiver-operator characteristic curve (> 8.34 m/s) as dependent variable, and measures with significance in univariate analysis as independent variables revealed that TA (OR 4.69; 95% CI 1.31–16.72; p = 0.017) and mean BP (OR 1.06; 95% CI 1.00–1.12; p = 0.048) were independently associated with higher PWV. Further analysis of disease variables revealed that PWV values were not correlated with erythrocyte sedimentation rate, C-reactive protein, cumulative dose of glucocorticoid, or ejection fraction (p > 0.05).

Conclusion.

In our cohort of female patients with TA, the disease itself and mean BP were the strongest determinants associated with arterial stiffness.

Lipoic acid, but not tempol, preserves vascular compliance and decreases medial calcification in a model of elastocalcinosis

Vascular calcification decreases compliance and increases morbidity. Mechanisms of this process are unclear. The role of oxidative stress and effects of antioxidants have been poorly explored. We investigated effects of the antioxidants lipoic acid (LA) and tempol in a model of atherosclerosis associated with elastocalcinosis. Male New Zealand white rabbits (2.5-3.0 kg) were fed regular chow (controls) or a 0.5% cholesterol (chol) diet+10⁴ IU/day vitamin D₂ (vitD) for 12 weeks, and assigned to treatment with water (vehicle, n=20), 0.12 mmol·kg^-1·day^-1 LA (n=11) or 0.1 mmol·kg^-1·day^-1 tempol (n=15). Chol+vitD-fed rabbits developed atherosclerotic plaques associated with expansive remodeling, elastic fiber disruption, medial calcification, and increased aortic stiffness. Histologically, LA prevented medial calcification by ∼60% and aortic stiffening by ∼60%. LA also preserved responsiveness to constrictor agents, while intima-media thickening was increased. In contrast to LA, tempol was associated with increased plaque collagen content, medial calcification and aortic stiffness, and produced differential changes in vasoactive responses in the chol+vitD group. Both LA and tempol prevented superoxide signals with chol+vitD. However, only LA prevented hydrogen peroxide-related signals with chol+vitD, while tempol enhanced them. These data suggest that LA, opposite to tempol, can minimize calcification and compliance loss in elastocalcionosis by inhibition of hydrogen peroxide generation.

A new risk score model to predict the presence of significant coronary artery disease in renal transplant candidates

BACKGROUND

Renal transplant candidates are at high risk of coronary artery disease (CAD). We sought to develop a new risk score model to determine the pre-test probability of the occurrence of significant CAD in renal transplant candidates.

METHODS

A total of 1,060 renal transplant candidates underwent a comprehensive cardiovascular risk evaluation. Patients considered at high risk of CAD (age ≥50 years, with either diabetes mellitus (DM) or cardiovascular disease (CVD)), or having noninvasive testing suggestive of CAD were referred for coronary angiography (n = 524). Significant CAD was defined by the presence of luminal stenosis ≥70%. A binary logistic regression model was built, and the resulting logistic regression coefficient B for each variable was multiplied by 10 and rounded to the next whole number. For each patient, a corresponding risk score was calculated and the receiver operating characteristic (ROC) curve was constructed.

RESULTS

The final equation for the model was risk score = (age × 0.4) + (DM × 9) + (CVD × 14) and for the probability of CAD (%) = (risk score × 2) - 23. The corresponding ROC for the accuracy of the diagnosis of CAD was 0.75 (P <0.0001) in the developmental model.

CONCLUSIONS

We developed a simple clinical risk score to determine the pre-test probability of significant CAD in renal transplant candidates. This model may help those directly involved in the care of patients with end-stage renal disease being considered for transplantation in an attempt to reduce the rate of cardiovascular events that presently hampers the long-term prognosis of such patients.

High muscle sympathetic nerve activity is associated with left ventricular dysfunction in treated hypertensive patients

BACKGROUND

The presence of asymptomatic left ventricular diastolic dysfunction (LVDD) in hypertensive patients can be associated with the development of cardiac events. The increase in sympathetic activity may be 1 of the mechanisms that predisposes to this outcome. In this study, we analyzed 2 hypotheses: (i) whether sympathetic activity is higher in the presence of LVDD, independent of blood pressure control and (ii) whether different classes of LVDD have a different effect on sympathetic activity.

METHODS

After analyzing left ventricular function using echo Doppler cardiography, 45 hypertensive patients receiving treatment were allocated into 3 groups: normal function (LV-NF, n = 15), impaired relaxation (LV-IR, n = 15), and pseudonormal or restrictive (LV-P/R, n = 15). An age-, sex-, and body mass index-matched control group of normotensive volunteers (N, n = 14) was included. Muscle sympathetic nerve activity (MSNA), heart rate, and systolic blood pressure variabilities and baroreflex sensitivity were evaluated while the patient was in a supine position.

RESULTS

Blood pressure and antihypertensive drug use were similar among the hypertensive groups. The LV-IR and LV-P/R groups had similar MSNA (33±1 and 32±1 bursts/min, respectively), which was significantly higher than that of the LV-NF and N groups (26±3 and 15±2 bursts/min, respectively). The LV-IR and LV-P/R groups had significantly higher LF-systolic blood pressure variability and significantly lower baroreflex sensitivity compared with the N group.

CONCLUSIONS

The presence of asymptomatic LVDD is associated with increased MSNA, independent of blood pressure control. The sympathetic hyperactivity associated with LVDD is similar in the different patterns of LVDD studied.

Distances walked in the six-minute walk test: suggestion of defining characteristic for the nursing diagnosis Ineffective Peripheral Tissue Perfusion

Distances walked in walking tests are important functional markers, although they are not accepted as defining characteristics of Ineffective Peripheral Tissue Perfusion. The aims of this study were to verify the distances participants with and without this nursing diagnosis walked in the six-minute walk test and if these measures may be considered defining characteristics of this phenomenon. Participants with (group A; n=65) and without (group B; n=17) this nursing diagnosis were evaluated regarding physical examination, vascular function and functional capacity. Participants of group A seemed to have worse vascular function and functional capacity compared with those of group B. Pain-free travelled distance was predictive of the nursing diagnosis. These results are important for the refinement of this diagnosis. In conclusion, this study provides evidences that the distances walked in the six-minute walk test may be considered defining characteristics of Ineffective Peripheral Tissue Perfusion.

Increased arterial stiffness assessed by pulse wave velocity in Behçet's disease and its association with the lipid profile

OBJECTIVE

To evaluate the structural and functional properties of vessels in Behçet's Disease (BD) using carotid-femoral pulse wave velocity (PWV) and an echo-tracking system.

METHODS

BD patients without traditional cardiovascular risk factors were selected. All BD patients performed PWV and carotid ultrasound. BD patients were divided into groups based on the presence of systemic (vascular and/or ocular and/or central nervous system involvement) and vascular involvement. Healthy controls age- and sex-matched with the same exclusion criteria were selected.

RESULTS

A total of 23 BD patients (mean age 35.0 ± 7.6 years) had significantly higher PWV levels compared with controls (8.48 ± 1.14 vs. 7.53 ± 1.40 m/s, P = 0.017). Intima-media thickness (594.87 ± 138.61 vs. 561.08 ± 134.26 μm, P = 0.371), diastolic diameter (6383.78 ± 960.49 vs. 6447.65 ± 1159.73 μm, P = 0.840), distension (401.95 ± 117.72 vs. 337.91 ± 175.36 μm, P = 0.225) and relative distension (6.26 ± 2.83 vs. 5.42 ± 2.46 μm, P = 0.293) were similar in both groups. The systemic disease group had significantly higher levels of PWV (8.79 ± 1.21 vs. 7.88 ± 0.72 m/s, P = 0.036) compared to those with exclusive mucocutaneous manifestations. BD patients with vascular involvement had similar PWV and echo-tracking parameters compared to those without vascular involvement (P > 0.05), but had higher total and LDL cholesterol levels (P = 0.019 and P = 0.012, respectively). The multivariate linear regression analysis identified triglycerides as the most important factor in increasing PWV levels (P = 0.001) in BD.

CONCLUSIONS

PWV is more useful than carotid ultrasound in detecting structural and functional vascular damage in BD and emphasizes the role of the disease itself in promoting these alterations. Our findings also reinforce the need for rigorous control of all risk factors in BD, particularly lipoproteins.