Diabetes mellitus, aortic stiffness, and cardiovascular mortality in end-stage renal disease

Association of bilateral brachial-ankle pulse wave velocity difference with peripheral vascular disease and left ventricular mass index

Unequal arterial stiffness had been associated with cardiovascular risks. We investigated whether an association existed between unequal arterial stiffness indicated by bilateral brachial-ankle pulse wave velocity (baPWV) difference and ankle-brachial index (ABI), baPWV, echocardiographic parameters and interarm and interankle systolic blood pressure (BP) differences. A total of 1111 patients referred for echocardiographic examination were included in this study. The BPs, ABI and baPWV were measured simultaneously by an ABI-form device. The ΔbaPWV was defined as absolute value of difference between bilateral baPWV. We performed three multivariate analyses for determining the factors associated with a ΔbaPWV ≧ 185 cm/s (90 percentile of ΔbaPWV) (model 1: significant variables in univariate analysis and ABI <0.9 and baPWV; model 2: significant variables in univariate analysis and left ventricular mass index [LVMI]; model 3: significant variables in univariate analysis and interankle systolic BP difference ≧ 15 mmHg). The ABI <0.9 and high baPWV (both P<0.001) in model 1, high LVMI (P = 0.021) in model 2 and an interankle systolic BP difference ≧ 15 mmHg (P = 0.026) in model 3 were associated with a ΔbaPWV ≧ 185 cm/s, but the interarm systolic BP difference ≧ 10 mmHg was not (P = NS). Our study demonstrated ABI <0.9, high baPWV, high LVMI and an interankle systolic BP difference ≧ 15 mmHg were associated with unequal arterial stiffness.

The association between arterial stiffness and fluid status in peritoneal dialysis patients

OBJECTIVES

In this study our aim was to evaluate the relationship between degree of fluid status and arterial stiffness measured by pulse wave velocity (PWV) in peritoneal dialysis (PD) patients. Fluid status was determined by different methods including fluid overload measured by bioimpedance (Body Composition Monitor, BCM), calf normalized resistivity (CNR), plasma N-terminal fragment of B-type natriuretic peptide (NT-proBNP) and extracellular to intracellular water ratio (ECW/ICW).

METHODS

Sixty PD patients were evaluated. They were stratified into normo- and hypervolemic groups according to their fluid overload (FO). CNR was calculated from resistance at 5 kHz using calf bioimpedance spectroscopy. Arterial stiffness was assessed by PWV. Additionally, all patients underwent transthoracic echocardiography and had levels of NT-proBNP measured.

RESULTS

PWV was higher in the hypervolemic compared to normovolemic patients (9.99 ± 2.4 m/sec vs 7.48 ± 2.3 m/sec, p < 0.001). Hypervolemic patients had higher NT-proBNP levels (3065 ± 981 pg/mL vs 1095 ± 502 pg/mL, p < 0.001), a higher ratio of ECW/ICW; (0.93 ± 0.11 vs 0.81 ± 0.08, p < 0.001) and lower CNR (13.7 ± 2.4 vs 16.0 ± 3.3 W m(3)/kg(*)10(-2), p = 0.005). NT-pro BNP level, ECW/ICW ratio, relative FO, and left ventricular (LV) mass index were positively and CNR negatively correlated with PWV. Relative FO and CNR independently predicted PWV in multivariate analysis adjusted for age, duration of PD, body mass index and mean arterial pressure.

CONCLUSIONS

Arterial stiffness is increased in fluid-overloaded PD patients. Our results indicated that fluid status is an independent predictor of PWV.

Aortic pulse wave velocity improves cardiovascular event prediction: an individual participant meta-analysis of prospective observational data from 17,635 subjects

OBJECTIVES

The goal of this study was to determine whether aortic pulse wave velocity (aPWV) improves prediction of cardiovascular disease (CVD) events beyond conventional risk factors.

BACKGROUND

Several studies have shown that aPWV may be a useful risk factor for predicting CVD, but they have been underpowered to examine whether this is true for different subgroups.

METHODS

We undertook a systematic review and obtained individual participant data from 16 studies. Study-specific associations of aPWV with CVD outcomes were determined using Cox proportional hazard models and random effect models to estimate pooled effects.

RESULTS

Of 17,635 participants, a total of 1,785 (10%) had a CVD event. The pooled age- and sex-adjusted hazard ratios (HRs) per 1-SD change in loge aPWV were 1.35 (95% confidence interval [CI]: 1.22 to 1.50; p < 0.001) for coronary heart disease, 1.54 (95% CI: 1.34 to 1.78; p < 0.001) for stroke, and 1.45 (95% CI: 1.30 to 1.61; p < 0.001) for CVD. Associations stratified according to sex, diabetes, and hypertension were similar but decreased with age (1.89, 1.77, 1.36, and 1.23 for age ≤50, 51 to 60, 61 to 70, and >70 years, respectively; pinteraction <0.001). After adjusting for conventional risk factors, aPWV remained a predictor of coronary heart disease (HR: 1.23 [95% CI: 1.11 to 1.35]; p < 0.001), stroke (HR: 1.28 [95% CI: 1.16 to 1.42]; p < 0.001), and CVD events (HR: 1.30 [95% CI: 1.18 to 1.43]; p < 0.001). Reclassification indices showed that the addition of aPWV improved risk prediction (13% for 10-year CVD risk for intermediate risk) for some subgroups.

CONCLUSIONS

Consideration of aPWV improves model fit and reclassifies risk for future CVD events in models that include standard risk factors. aPWV may enable better identification of high-risk populations that might benefit from more aggressive CVD risk factor management.

Aortic pulse wave velocity is a strong predictor of all--cause and cardiovascular mortality in chronic dialysis patients

BACKGROUND/AIMS

The aim of this study was to investigate all-cause and cardiovascular mortality in chronic hemodialysis patients (CHP) and to identify the determinants of mortality predictors.

METHODS

In this study with 3 years of follow-up period, we studied a cohort of 80 CHPs. Mean age at entry was 59.3 ± 11.8 years (duration of dialysis 5.47 ± 5.16 years). At entry, together with standard clinical and biochemical analyses, pulse wave velocity (PWV) was determined from time diversity propagation of the common carotid artery and common femoral artery flow signals by Doppler ultrasound.

RESULTS

The mean PWV (m/s) was presented at entry: in survived (12.5 ± 2.01) and deceased (13.13 ± 1.70) patients. The PWV cutoff point (by ROC curves) was 11.8. The regression coefficients (b) and Exp (b) hazard ratio coefficients of covariates in Cox-regression survival analysis in all-cause and CV outcomes was: PWV (b = 0.2617, Exp[b] = 1.2992, p = 0.0027; b = 0.3569, Exp[b] = 1.4289, p = 0.0005), CRP (b = 0.0776, Exp[b] = 1.0807, p = 0.0001; b = 0.0832, Exp[b] = 1.0868, p = 0.0001) and albumin (b = -0.1302, Exp[b] = 0.8779, p = 0.0089; b = -0.1881, 0.8285, p = 0.0030), respectively. Relative risk for exposed groups according to all-cause and CV events was 4.2976 (95% CI = 1.6051-11.5071) and 14.3590 (95% CI = 1.6051-11.5071), p = 0.0037, respectively.

CONCLUSIONS

We conclude that PWV, CRP and serum albumin are strong independent predictors of overall and CV mortality in patients undergoing dialysis.

Assessment of arterial stiffness for clinical and epidemiological studies: methodological considerations for validation and entry into the European Renal and Cardiovascular Medicine registry

Epidemiological studies have highlighted the role of arterial stiffness as a risk factor for development of cardiovascular (CV) diseases. Moreover, aortic stiffness has been shown to be a significant predictive factor of all-cause and CV mortality in different populations including patients with end-stage renal disease. Pulse-wave velocity (PWV) is the most widely used technique to assess arterial stiffness. Although PWV can be measured on any artery or between any arterial sites, only carotid-to-femoral PWV, representing stiffness of the aorta and iliofemoral axes, has been shown to have predictive value for morbidity and mortality. The several available commercial devices differ according to the type of signal (pressure, distension, flow) or by recording both sites simultaneously or using ECG synchronization. It is also possible to directly measure arterial diameter changes during the cardiac cycle and link them to local pulse-pressure changes, which provides the pressure-diameter relationship and stress-strain relationship if arterial wall thickness is also measured. These techniques are based on high-precision vascular echo tracking or magnetic resonance imaging and applanation tonometry. This paper summarizes the basic principles of arterial haemodynamics and various methodologies to assess stiffness and the latest consensus recommendations for clinical applications.

Increased Aortic Stiffness Predicts Contrast-Induced Nephropathy in Patients With Stable Coronary Artery Disease Undergoing Percutaneous Coronary Intervention

Increased aortic stiffness (AS) has been shown to be an independent risk factor for cardiovascular disease in renal failure and was also found to be associated with even mild renal insufficiency. We investigated the relationship between contrast-induced nephropathy (CIN) and AS parameters such as pulse wave velocity (PWV) and augmentation index (AIx). Patients (n = 440) with stable coronary artery disease (CAD) treated with percutaneous coronary intervention (PCI) were included prospectively (mean age: 60.3 ± 10.3 years). The PWV and AIx were calculated using the single-point method. The PWV, age, diabetes, SYNTAX score, and contrast media dose were independent predictors for CIN ( P < .05, for all). The cutoff value for PWV obtained by the receiver–operator characteristic curve analysis was 10.35 m/s for the prediction of CIN (95% confidence interval: 0.838-0.916, sensitivity: 82.1%, specificity: 77.9%, and P < .001). In conclusion, a greater AS pre-PCI may predict CIN development in patients with stable CAD.

Effect of beraprost sodium on arterial stiffness in patients with type 2 diabetic nephropathy

Background

Diabetic nephropathy is the leading cause of end-stage renal disease (ESRD). Cardiovascular (CV) complications are the most common cause of death among ESRD patients. Beraprost sodium (BPS) is a prostacyclin analog with vasodilatory and antiplatelet effects.

Methods

This is a multicenter prospective, randomized, double-blind, placebo-controlled trial to determine whether treatment with BPS improves arterial stiffness in patients with type 2 diabetic nephropathy. A total of 102 participants with type 2 diabetic nephropathy will be screened, enrolled, and randomly assigned to receive either 80 μg BPS or placebo daily for 12 weeks. The primary outcome is the change in brachial-ankle pulse wave velocity between baseline and after 12 weeks of medication use. The secondary outcomes will include changes in the ankle-brachial index, the urine albumin to creatinine ratio, the estimated glomerular filtration rate, lipid profiles, and blood pressure from baseline to after treatment.

Discussion

This clinical trial is the first to investigate the effects of BPS on changes in CV biomarkers, albuminuria, renal function, and lipid profiles in patients with diabetic nephropathy.

Trial registration

ClinicalTrials.gov number NCT01796418

Insulin resistance and the metabolic syndrome are associated with arterial stiffness in patients with chronic kidney disease

BACKGROUND

Insulin resistance (IR) and the metabolic syndrome (MetS) may contribute to cardiovascular risk in chronic kidney disease (CKD). We examine the association between IR and vascular function in CKD. Furthermore, we define the prevalence of MetS and examine the association between defining MetS and vascular function.

METHODS

This cross-sectional study of 71 stage 3-4 CKD subjects assessed arterial stiffness (pulse wave velocity (PWV) and endothelial dysfunction (ED). IR was assessed using Homeostasis Model Assessment-IR (HOMA-IR). MetS was defined by the unified International Diabetes Federation and American Heart Association/National Heart Lung and Blood Institute criteria.

RESULTS

CKD subjects with HOMA-IR score above the median had significantly higher body mass index and waist circumference. They also had higher PWV, higher triglycerides with lower high-density lipoprotein concentration (P < 0.05). Age, systolic blood pressure, and HOMA-IR were independently associated with PWV, even after exclusion of diabetic subjects (n = 16) (P ≤ 0.05). MetS was more prevalent in CKD (78.9%) than controls (2.5%). MetS in CKD was associated with increased PWV (MetS(+) geometric mean = 9.5 m/s, 95% confidence interval (95% CI) = 8.9-10.2 m/s; vs. MetS(-) 8.1 m/s, 95% CI = 7.1-9.3 m/s; P = 0.03) but not ED. In a multiple logistic regression analysis, PWV higher than the median was independently associated with dysglycemia.

CONCLUSIONS

IR is independently associated with arterial stiffness, even in nondiabetic CKD. MetS is common and identified a subgroup of CKD patients with increased arterial stiffness, which is associated with dysglycemia.

Reproducibility of arterial stiffness and wave reflections in chronic obstructive pulmonary disease: the contribution of lung hyperinflation and a comparison of techniques

Significant cardiovascular morbidity and mortality exists in chronic obstructive pulmonary disease (COPD). Arterial stiffness is raised in COPD and may be a mechanistic link. Non-invasive assessment of arterial stiffness has the potential to be a surrogate outcome measure, although no reproducibility data exists in COPD patients. Two studies (23 and 33 COPD patients) were undertaken to 1) assess the Vicorder reproducibility of carotid-femoral pulse wave velocity and Augmentation index in COPD; 2) compare it to SphygmoCor; and 3) assess the contribution of lung hyperinflation to measurement variability. There were excellent correlations and good agreement between repeat Vicorder measurements for carotid-femoral pulse wave velocity (r = 0.96 (p < 0.001); mean difference ±SD = -0.03 ± 0.36 m/s (p = 0.65); co-efficient of reproducibility = 4.02%; limits of agreement = -0.68-0.75 m/s). Augmentation index significantly correlated (r = 0.736 (p < 0.001); mean difference ±SD = 0.72 ± 4.86% (p = 0.48), however limits of agreement were only 10.42-9.02%, with co-efficient of reproducibility of 27.93%. Comparing devices, Vicorder values were lower but there was satisfactory agreement. There were no correlation between lung hyperinflation (as measured by residual volume percent predicted, total lung capacity percent predicted or the ratio of inspiratory capacity to residual volume) and variability of measurements in either study. In COPD, measurement of carotid-femoral pulse wave velocity is highly reproducible, not affected by lung hyperinflation and suitable as a surrogate endpoint in research studies. Day-to-day variation in augmentation index highlights the importance of such studies prior to the planning and undertaking of clinical COPD research.

Increased pulse wave velocity and carotid intima-media thickness in patients with ulcerative colitis

BACKGROUND

Ulcerative colitis (UC) is characterized with chronic, progressive inflammation of the gastrointestinal tract. The association of UC with cardiovascular disease is still a matter of debate.

AIM

The aim of this study was to investigate whether carotid intima-media thickness (CIMT) and carotid-femoral pulse wave velocity (cf-PWV) as surrogates of atherosclerosis and arterial stiffness are increased in patients with UC.

METHODS

Our study was cross-sectional and observational in design. Baseline characteristics were recorded during interview with the patient. Patients with previous cardiovascular disease, rheumatoid arthritis, chronic renal failure, and infectious and inflammatory disorders other than UC were excluded. Thirty-seven consecutive patients with UC and 30 control participants underwent cf-PWV assessment and CIMT measurement. The diagnosis of UC was based on clinical, radiologic, endoscopic, and histological findings.

RESULTS

CIMT, cf-PWV, and C reactive protein were significantly higher in patients with UC. Although linear regression analyses identified UC as an independent predictor of CIMT (β ± SE, 0.39 ± 0.08; p < 0.001), only age independently predicted cf-PWV (β ± SE, 0.08 ± 0.03; p = 0.003) in our study population. Moreover, we revealed higher CIMT and PWV values in patients with higher disease activity and more extensive involvement, compared to patients with mild activity and limited disease.

CONCLUSION

We revealed increased pulse wave velocity and CIMT in patients with UC. UC appears to be associated with arterial stiffness and atherosclerotic burden, but the underlying mechanisms require further studies to be identified.

Association of the cardioankle vascular index and ankle-brachial index with carotid artery intima media thickness in hemodialysis patients

The objectives of the present study are (1) to compare the cardioankle vascular index (CAVI), ankle-brachial index (ABI), and carotid artery intima-media thickness (CA-IMT) between HD patients with and without type 2 diabetes (T2D) or prevalence of cardiovascular (CV) disease and (2) also to evaluate the relationship of these indices with CA-IMT in these patients according to ABI levels. This study consisted of 132 HD patients with T2D and the same number of patients without T2D. The patients with diabetes or prevalence of CV disease had significantly higher CA-IMT and lower ABI values than those without diabetes or prevalence of CV disease, respectively. Although diabetic patients had higher CAVI than those without diabetes, CAVI did not differ between patients with or without prevalence of CV disease. In univariate analysis, CA-IMT was more strongly correlated with ABI than CAVI. However, the opposite was true in patients with an ABI value of more than 0.95. Both indices were significantly correlated with CA-IMT although ABI was a powerful determinant than CAVI. It appears that both indices are associated with CA-IMT in HD patients, especially with an ABI value of more than 0.95.

Atomic force microscopy images label-free, drug encapsulated nanoparticles in vivo and detects difference in tissue mechanical properties of treated and untreated: a tip for nanotoxicology

Overcoming the intractable challenge of imaging of label-free, drug encapsulated nanoparticles in tissues in vivo would directly address associated regulatory concerns over 'nanotoxicology'. Here we demonstrate the utility of Atomic Force Microscopy (AFM) for visualising label-free, drug encapsulated polyester particles of ∼280 nm distributed within tissues following their intravenous or peroral administration to rodents. A surprising phenomenon, in which the tissues' mechanical stiffness was directly measured (also by AFM) and related to the number of embedded nanoparticles, was utilised to generate quantitative data sets for nanoparticles localisation. By coupling the normal determination of a drug's pharmacokinetics/pharmacodynamics with post-sacrifice measurement of nanoparticle localisation and number, we present for the first time an experimental design in which a single in vivo study relates the PK/PD of a nanomedicine to its toxicokinetics.

Arterial stiffness, carotid atherosclerosis and left ventricular diastolic dysfunction in postmenopausal women

BACKGROUND

Postmenopausal women have an increased cardiovascular morbidity that may be due to the increase in classical cardiovascular risk factors and also to the arterial structure and function alterations. The aim of our study was to evaluate the association of aortic pulse wave velocity (PWV), and carotid intima-media thickness (IMT), with left ventricular diastolic dysfunction (LVDD) in postmenopausal women.

PATIENTS AND METHODS

In 96 women without overt cardiovascular disease (age 62±7.7 years), and with normal left ventricular systolic function, aortic PWV was assessed by using an oscillometric device, intima-media thickness was measured by B-mode ultrasonography and the parameters of left ventricular diastolic function were evaluated by a transthoracic echocardiographic study.

RESULTS

LVDD, defined as an E/A ratio≤1 was found in 50 patients (52%). All of them had mild LVDD. In these patients we found significant increase in age (p<0.001), aortic PWV (p<0.001), carotid IMT (p=0.002) and plaque score (p=0.004) when compared with patients without LVDD. In a logistic regression analyzed, after adjusting for age, only aortic PWV was a significant predictor of LVDD (2.15, 95% CI 1.39-3.31, p=0.0006).

CONCLUSIONS

This study among postmenopausal women provides evidence that increased arterial stiffness as measured by aortic PWV and not carotid IMT may be a marker or a risk factor for LVDD, independent of other classical risk factors.

Pulse Wave Velocity in Postmenopausal Women

Cardiovascular disease (CVD) and osteoporosis are major causes of morbidity and mortality in postmenopausal women. The relationship between atherosclerosis and osteoporosis has been established by studies of the underlying pathophysiological mechanisms and biochemical pathways that seem to overlap in many places. Pulse wave velocity (PWV) is one of the known predictors of cardiovascular and all-cause mortality. Studies indicate that PWV in hypertensive postmenopausal women is increased, and hormone replacement therapy (HRT) attenuates this increase. In addition, recently, many studies have suggested a role for arterial stiffness in the association between CVD and osteoporosis. From these findings, it appears that estrogen deficiency combined with production of inflammatory cytokines plays a role in increased PWV closely associated with CVD and osteoporosis, although the mechanisms of arterial stiffness in postmenopausal women may be more complex. Accordingly, a possible role for PWV as a surrogate marker of CVD as well as osteoporosis in postmenopausal women is discussed in this review. First, menopause leads to increased arterial stiffness with aging in females. Further, epidemiological data evaluating arterial stiffness assessed by PWV provided evidence that most of the established CVD risk factors are determinants of PWV, and these risk factors are increased in patients with CVD. In turn, contrary to expectation, HRT did not always contribute to a lower incidence of CVD in postmenopausal women. By reviewing the current data available, it becomes clear that, at present, the effects of menopause including HRT on PWV remain controversial, and further studies are needed to clarify these associations.

Arterial stiffness predicts risk for long-term recurrence in patients with type 2 diabetes admitted for acute coronary event

OBJECTIVES

to investigate the predictive value of arterial stiffness (AS) estimation for long-term recurrences in patients with type 2 diabetes (DM2) following acute coronary event.

PATIENTS AND METHODS

prospective observational study involving 119 DM2 patients without history of coronary heart disease admitted with ST-segment elevation myocardial infarction (STEMI). Medical history, anthropometrics, smoking, HbA1c, lipid profile, troponine-I levels, and left ventricular ejection fraction (LVEF) were recorded. Carotid-femoral pulse wave velocity (cf-PWV) was measured 1 month after discharge. Patients were followed up for 36 months or to reach an end-point: cardiovascular death, acute coronary event, angioplasty or hospitalization for acute heart failure. To facilitate analysis, patients were divided into two groups according to cf-PWV, using the accepted cut-off value of 12m/s.

RESULTS

overall, 34 patients had a recurrence. In Kaplan-Meier analysis patients with cf-PWV>12m/s had mean time-to-event 353±43 days compared to 505±115 days for patients with cf-PWV≤12m/s, log rank=0.0252. In multivariate analysis factors independently associated with recurrence were age (66.53±6.87 vs. 61.54±10.77 years, p=0.015), LVEF (41.66±8.21 vs. 47.58±8.11%, p=0.001) and cf-PWV (13.94±2.91 vs. 12.35±2.77m/s, p=0.008).

CONCLUSIONS

AS estimation in patients with DM2 after STEMI discriminate patients at higher risk for 3-year recurrence, and maybe valuable for distinguishing patients likely to require a more rigorous therapeutic intervention.

Increased pulse wave velocity in patients with panic disorder: independent vascular influence of panic disorder on arterial stiffness

OBJECTIVE

Acute and chronic mental stress and many psychiatric disorders have been accepted as a cause of cardiovascular disease. Panic disorder, a subtype of anxiety disorder, has been associated with increased risk of fatal myocardial infarction and sudden cardiac death in epidemiological studies. Carotid-femoral pulse wave velocity (CF-PWV) is currently the gold standard measurement of arterial stiffness. CF-PWV is a well-recognized predictor of an adverse cardiovascular outcome with higher predictive value than classical cardiovascular risk factors. The aim of our study is to measure PWV as the surrogate of arterial stiffness and vascular involvement in patients with panic disorder.

METHODS

Forty-two patients with PD, and 30 control participants were included in the study. Patients with hypertension, diabetes mellitus, or the history of any cardiovascular disease were excluded from study.

RESULTS

Baseline characteristics were not significantly different between the two groups, except carotid-femoral pulse wave velocity (PD vs. control; 7.51±2.02 vs. 6.24±1.09 m/s, p=0.001), heart rate, and smoking status. Additionally, CF-PWV positively correlated with age (r=0.250, p=0.034), heart rate (r=0.284, p=0.017), systolic and diastolic blood pressure (r=0.393, p=0.001 and r=0.286, p=0.015, respectively) significantly. However, only the presence of panic disorder was independently related to PWV (βeta: 0.317, p=0.011) in the multivariate analysis including age, heart rate, smoking status and blood pressure measurements.

CONCLUSION

Increased pulse wave velocity in patients with panic disorder may justify the associated risk as documented in previous studies, and may be useful in identifying the patients with higher risk of future cardiovascular complications.

Urinary corticosteroid excretion predicts left ventricular mass and proteinuria in chronic kidney disease

Blockade of the MR (mineralocorticoid receptor) in CKD (chronic kidney disease) reduces LVMI [LV (left ventricular) mass index] and proteinuria. The MR can be activated by aldosterone, cortisol and DOC (deoxycorticosterone). The aim of the present study was to explore the influence of mineralocorticoids on LVMI and proteinuria in patients with CKD. A total of 70 patients with CKD and 30 patients with EH (essential hypertension) were recruited. Patients underwent clinical phenotyping; biochemical assessment and 24 h urinary collection for THAldo (tetrahydroaldosterone), THDOC (tetrahydrodeoxycorticosterone), cortisol metabolites (measured using GC–MS), and urinary electrolytes and protein [QP (proteinuira quantification)]. LVMI was measured using CMRI (cardiac magnetic resonance imaging). Factors that correlated significantly with LVMI and proteinuria were entered into linear regression models. In patients with CKD, significant predictors of LVMI were male gender, SBP (systolic blood pressure), QP, and THAldo and THDOC excretion. Significant independent predictors on multivariate analysis were THDOC excretion, SBP and male gender. In EH, no association was seen between THAldo or THDOC and LVMI; plasma aldosterone concentration was the only significant independent predictor. Significant univariate determinants of proteinuria in patients with CKD were THAldo, THDOC, USod (urinary sodium) and SBP. Only THAldo excretion and SBP were significant multivariate determinants. Using CMRI to determine LVMI we have demonstrated that THDOC is a novel independent predictor of LVMI in patients with CKD, differing from patients with EH. Twenty-four hour THAldo excretion is an independent determinant of proteinuria in patients with CKD. These findings emphasize the importance of MR activation in the pathogenesis of the adverse clinical phenotype in CKD.

C-reactive protein is associated with aortic stiffness in a cohort of African American and white women transitioning through menopause

OBJECTIVE

Arterial stiffness is a marker of cardiovascular health. Arterial stiffness and C-reactive protein (CRP) are linked to cardiovascular outcomes. Increases in both inflammation and arterial stiffness are known to occur with menopause. The association between CRP and arterial stiffness is well accepted; however, no study has determined whether there are differences in this association by menopause status and race, independent of age.

METHODS

The cross-sectional association between CRP and aortic pulse wave velocity (PWV), a validated measure of central arterial stiffening, was evaluated in 307 African American and white women enrolled in an ancillary study to the Study of Women's Health Across the Nation. Women were categorized into premenopausal or early perimenopausal (n = 185) and late perimenopausal or postmenopausal (n = 122).

RESULTS

Natural log-transformed CRP was not associated with PWV in a linear regression model adjusted for age and cardiovascular risk factors (β = 15.9, P = 0.11). Moreover, models stratified by menopause status showed a linear relationship between CRP and PWV among late perimenopausal or postmenopausal women (β = 36.2, P = 0.049) but not for premenopausal or early perimenopausal women (β = 5.9, P = 0.61). The menopause status × log-transformed CRP and menopause status × race interactions were significant in their respective models adjusted for age and risk factors (P = 0.03 for both); however, when combined into one model, the two interactions were slightly attenuated (P = 0.063 and 0.052, respectively).

CONCLUSIONS

Menopause is strengthening the association between CRP and PWV, independent of age, and this effect seems to be stronger among African American women. This study provides a potential mechanism for the increased risk of cardiovascular disease among postmenopausal women.

The association between preeclampsia and arterial stiffness

A systematic review and meta-analysis was conducted using MEDLINE, EMBASE, and the Cochrane Library to investigate the association between preeclampsia and arterial stiffness. Twenty-three relevant studies were included. A significant increase in all arterial stiffness indices combined was observed in women with preeclampsia vs. women with normotensive pregnancies [standardized mean difference 1.62, 95% confidence interval (CI) 0.73-2.50]; carotid-femoral pulse wave velocity (cfPWV) and augmentation index (AIx) were also significantly increased (weighted mean difference, WMDcfPWV 1.04, 95% CI 0.34-1.74; WMDAIx 15.10, 95% CI 5.08-25.11), whereas carotid-radial PWV (crPWV) increase did not reach significance (WMDcrPWV 0.99, 95% CI -0.07 to 2.05). Significant increases in arterial stiffness measurements were noted in women with preeclampsia compared with those with gestational hypertension. Arterial stiffness measurements may also be useful in predicting preeclampsia and may play a role in the increased risk of future cardiovascular complications seen in women with a history of preeclampsia.

Arterial stiffness contributes to coronary artery disease risk prediction beyond the traditional risk score (RAMA-EGAT score)

Objectives

The traditional risk score (RAMA-EGAT) has been shown to be an accurate scoring system for predicting coronary artery disease (CAD). Arterial stiffness measured by the cardio–ankle vascular index (CAVI) is known to be a marker of atherosclerotic burden. A study was undertaken to determine whether CAVI improves the prediction of CAD beyond the RAMA-EGAT score.

Design

Cross-sectional study.

Patients

Patients with a moderate to high risk for CAD by the RAMA-EGAT score were enrolled between November 2005 and March 2006. 64-slice multidetector CT coronary angiography was used to evaluate the coronary artery calcium score and coronary stenosis. Arterial stiffness was assessed by CAVI.

Results

1391 patients of median age 59 years (range 31–88) were enrolled in the study, 635 (45.7%) men and 756 (54.3%) women. Of the 1391 patients, 346 (24.87%) had coronary stenosis. There was a correlation between CAVI and the prevalence of coronary stenosis after adjusting for traditional CAD risk factors (OR 3.29). In addition, adding CAVI into the RAMA-EGAT score (modified RAMA-EGAT score) improved the prediction of CAD incidence, increasing C-statistics from 0.72 to 0.85 and resulting in a net reclassification improvement of 27.7% (p<0.0001).

Conclusion

CAVI is an independent risk predictor for CAD. The addition of CAVI to the RAMA-EGAT score significantly improves the diagnostic yield of CAD.

Systemic vascular hemodynamics and transplanted kidney survival

INTRODUCTION

High blood pressure and arterial stiffness contribute independently to cardiovascular mortality in uremic patients. High blood pressure is an established risk factor for chronic allograft nephropathy, recently named interstitial fibrosis/tubular atrophy (IF/TA). We sought to assess whether heart afterload determinants: arterial stiffness and vascular resistance or impedance accelerate kidney graft failure upon long-term observation.

METHODS

Using a noninvasive method of blood pressure waveform analysis, (HDI/PulseWave/CR-2000), we studied 160 consecutive kidney transplant recipients, who were at least 3 months after transplantation, for systolic (SBP), diastolic, and mean blood pressure; pulse rate; systemic vascular resistance and impedance as well as large and small artery compliance. The associations of the hemodynamic parameters with relative increases in serum creatinine for every year of graft survival (ΔCreat) were assessed using multiple linear regression analysis. Relationships between systemic hemodynamics and kidney graft loss due to IF/TA were evaluated by Cox regression analysis, including serum creatinine, time after transplantation, delayed graft function, human leukocyte antigen mismatch, panel-reactive antibodies, cold ischemia time, donor age glomerular filtration rate as well as prescribed cardiovascular and immunosuppressive drugs.

RESULTS

Over 6.6±0.4 years of follow-up, excluding four noncompliant patients, 11 patients died and 32 lost their kidney grafts, including 25 due to IF/TA. ΔCreat (10.3%±22.0%/y) was independently and positively associated with the initial SBP (β=0.26; P=.001) and serum creatinine values (β=0.16; P=.04). The risk of graft loss due to IF/TA was greater among patients with an increased serum creatinine (relative risk [RR]=59.5 per nlog-unit increase; P<.001) or higher SBP (RR=51.1 per nlog-unit increase; P=.04). Besides SBP, no other hemodynamic parameter was associated with graft failure.

CONCLUSIONS

The rate of kidney graft function deterioration and risk of transplant loss due to IF/TA are not independently influenced by systemic arterial compliance, resistance, or impedance. SBP appears to be the key circulatory parameter independently affecting the progression of IF/TA, and should be a therapeutic target.

Relation of carotid intima-media thickness and silent cerebral infarction to cardiovascular events and all-cause mortality in chronic hemodialysis patients

OBJECTIVE

Silent cerebral infarction (SCI) and increased carotid intima-media thickness (IMT) have been found to be associated with future stroke in the general population. We investigated whether a combination of SCI and increased IMT is a predictor of cardiovascular events and all-cause mortality in chronic hemodialysis (HD) patients.

METHODS

We performed a retrospective cohort study of 70 HD patients who had one or more risk factors for atherosclerosis but no history of cardiovascular disease. We performed cranial magnetic resonance imaging (MRI) and measured carotid IMT at baseline, and then evaluated the risks of cardiovascular events and all-cause mortality by using Cox proportional hazards models. The Kaplan-Meier method and a log-rank test were used to compare event-free survival.

RESULTS

SCI was present in 25 patients (35.7%) at baseline. During an average follow-up of 46.3 ± 14.3 months (range: 19 to 56 months), 15 patients (21.4%) died and 16 (22.9%) experienced a new cardiovascular event. The presence of SCI in combination with increased carotid IMT at baseline was independently associated with cardiovascular events and all-cause mortality after adjustment for age, sex, duration of dialysis, and traditional vascular risk factors.

CONCLUSION

SCI, similar to carotid IMT, is an independent predictor of cardiovascular events and all-cause mortality in chronic HD patients.

[A statistical definition of aortic pulse wave velocity normality in a Portuguese population: a subanalysis of the EDIVA project]

INTRODUCTION

Aortic pulse wave velocity (PWV) has been associated with cardiovascular risk in different clinical subsets. This subanalysis of the EDIVA project aimed to establish criteria for normality of PWV based on a statistical definition that considers the fundamental physiological role of aging in arterial stiffness.

METHODS

A sample of 668 healthy subjects (412 male) enrolled in the EDIVA Project (a prospective, multicenter, observational study) were studied. Mean age was 40.00 ± 13.42 years, body mass index was 25.90 ± 4.21kg/m(2), and systolic and diastolic blood pressure were respectively 125.47 ± 11.18 and 75.75 ± 9.27mmHg. PWV was determined annually using a Complior device, and mean follow-up was 23.3 ± 3.34 months. Personal and family history, physical examination, electrocardiogram and biochemical analysis were used to determine individual health.

RESULTS

In the overall population PWV was 8.8 ± 1.4m/sec, 8.7 ± 1.6m/sec in men and 8.9 ± 1.5m/sec in women (p=NS). Normal PWV was defined as the 95th percentile adjusted for age and gender, above which PWV was considered abnormal. Serial evaluation of PWV also enabled the annual age-dependent increase in PWV to be estimated at 5%, values above this cut-off being defined as abnormal vascular deterioration.

CONCLUSION

This study establishes criteria for normality based on a statistical definition that takes into account the fundamental physiological role of aging in arterial stiffness. Additionally, it provides a cut-off for the clinical interpretation of serial PWV measurements.

Arterial stiffness, central hemodynamics, and cardiovascular risk in hypertension

This review summarizes several scientific contributions at the recent Satellite Symposium of the European Society of Hypertension, held in Milan, Italy. Arterial stiffening and its hemodynamic consequences can be easily and reliably measured using a range of noninvasive techniques. However, like blood pressure (BP) measurements, arterial stiffness should be measured carefully under standardized patient conditions. Carotid-femoral pulse wave velocity has been proposed as the gold standard for arterial stiffness measurement and is a well recognized predictor of adverse cardiovascular outcome. Systolic BP and pulse pressure in the ascending aorta may be lower than pressures measured in the upper limb, especially in young individuals. A number of studies suggest closer correlation of end-organ damage with central BP than with peripheral BP, and central BP may provide additional prognostic information regarding cardiovascular risk. Moreover, BP-lowering drugs can have differential effects on central aortic pressures and hemodynamics compared with brachial BP. This may explain the greater beneficial effect provided by newer antihypertensive drugs beyond peripheral BP reduction. Although many methodological problems still hinder the wide clinical application of parameters of arterial stiffness, these will likely contribute to cardiovascular assessment and management in future clinical practice. Each of the abovementioned parameters reflects a different characteristic of the atherosclerotic process, involving functional and/or morphological changes in the vessel wall. Therefore, acquiring simultaneous measurements of different parameters of vascular function and structure could theoretically enhance the power to improve risk stratification. Continuous technological effort is necessary to refine our methods of investigation in order to detect early arterial abnormalities. Arterial stiffness and its consequences represent the great challenge of the twenty-first century for affluent countries, and "de-stiffening" will be the goal of the next decades.

Arterial stiffness is associated with incident albuminuria and decreased glomerular filtration rate in type 2 diabetic patients

OBJECTIVE

To investigate the association between aortic stiffness and incident albuminuria and the decline in estimated glomerular filtration rate (eGFR) in patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

We investigated 461 Japanese type 2 diabetic patients, comprising 199 women and 262 men, with a mean age of 59 ± 11 years. Patients were divided into two groups according to the median value of carotid-femoral pulse wave velocity (cf-PWV), which was used to evaluate aortic stiffness. The end point was defined as the transition from normo- to microalbuminuria or micro- to macroalbuminuria. The Cox proportional hazard model was used to calculate the hazard ratio (HR) and 95% CI. The correlation between cf-PWV and rate of change in eGFR was also determined by linear regression analysis.

RESULTS

The baseline mean (± SD) cf-PWV was 9.6 ± 2.4 m/s. During a median follow-up period of 5.9 years (range 0.3-8.6), progression of albuminuria was observed in 85 patients. The 5-year cumulative incidence of the end point in patients with cf-PWV below and above the median was 8.5 and 19.4%, respectively (P = 0.002, log-rank test). cf-PWV was significantly associated with incident albuminuria (HR 1.23, 95% CI 1.13-1.33, P < 0.001) by multivariate Cox regression analysis. A significant association between cf-PWV and annual change in eGFR was also suggested by multiple linear regression analysis (standardized estimate -0.095, P = 0.031).

CONCLUSIONS

Aortic stiffness is associated with incident albuminuria and the rate of decline in glomerular filtration rate in type 2 diabetic patients.

Non-high-density lipoprotein cholesterol and its correlation with anthropometric markers of cardiovascular risk in hemodialysis

INTRODUCTION

Non-high-density lipoprotein cholesterol (non-HDL-c) may be a better indicator of atherogenicity in the hemodialysis population.

PURPOSE

To investigate the correlation of non-HDL-c with anthropometric measurements associated to cardiovascular risk, such as body mass index, waist circumference, waist-to-height ratio, waist-to-height(2) ratio, and waist-to-hip circumference ratio.

METHODS

We evaluated anthropometric markers and lipids in 86 hemodialysis patients, and the correlation between them was investigated.

RESULTS

Non-HDL-c had a positive correlation with body mass index (r = 0.273; P = .01), waist circumference (r = 0.375; P = .000), waist-to-height ratio (r = 0.333; P = .002), waist-to-height(2) ratio (r = 0.270; P = .012), and waist-to-hip circumference ratio (r = 0.356; P = .001).

CONCLUSIONS

This study detected a positive and significant correlation between non-HDL-c, but not low-density lipoprotein cholesterol, and the anthropometric cardiovascular risk indexes. We could suggest that non-HDL-c can be used as a cardiovascular risk factor indicator among dialysis patients.

Arterial stiffness: from physiology to clinical implications

Current European guidelines for the management of arterial hypertension introduce the assessment of arterial stiffness by pulse wave velocity (PWV) as an index of hypertension-related cardiovascular target organ damage. An increase in arterial stiffness is related to haemodynamic modifications at the level of the aorta, leading to a rise in cardiac afterload, a reduction in coronary perfusion and an overstretch of the aortic walls. An increasing number of studies have demonstrated the accuracy of PWV as an independent predictor of cardiovascular events and cardiovascular mortality in patients with different co-morbidities and cardiovascular risk. Many strategies have demonstrated their efficacy in preventing arterial stiffening; therapy of arterial hypertension is the mainstay in the management of patients with increased PWV and altered pulse wave reflection. Literature has clearly shown the specific efficacy of drugs interfering with the renin-angiotensin-aldosterone system and calcium-channel blockers in the control of central haemodynamics, particularly when compared with β-blockers (β-adrenoceptor antagonists). The same action has not yet been demonstrated on PWV. Further studies are needed to assess the real relative efficacy of different drug classes on the management of arterial stiffness and the clinical and prognostic relevance of these therapies.

Comparison of serum albumin, serum C-reactive protein, and pulse wave velocity as predictors of the 4-year mortality of chronic hemodialysis patients

AIM

Although serum albumin and C-reactive protein (CRP) levels and pulse wave velocity (PWV) are known to be associated with the clinical outcome of hemodialysis (HD) patients, it is unknown which of these parameters are more predictive of the long-term mortality of such patients.

METHODS

We measured biochemical parameters, including serum albumin and CRP, and the PWV of 202 patients on maintenance HD therapy and followed their course for 4 years, and 186 of the patients were enrolled in the current study analyses. We divided the 186 patients into three tertiles according to their serum albumin and CRP levels and PWV values, and conducted multivariate analyses to examine the impact of the tertiles on 4-year mortality.

RESULTS

Twenty-three (12.4%) patients died during the follow-up period, and the serum albumin of the group that died was significantly lower than in the group that survived, but the CRP levels and PWV were significantly higher in the group that died. The results of Kaplan-Meier analyses revealed a significantly higher risk of all-cause mortality in HD patients with higher CRP based on the results of Cox proportional hazards analyses; however, the serum albumin and PWV values were not associated with all-cause mortality.

CONCLUSION

The results of this study suggest that serum CRP levels are a better mortality predictor than serum albumin or PWV values of chronic HD patients.

Angiotensin-converting enzyme inhibitor limits pulse-wave velocity and aortic calcification in a rat model of cystic renal disease

The effect of angiotensin-converting enzyme inhibition on function and structure of the aorta was studied in the Lewis polycystic kidney (LPK) rat model of cystic renal disease and Lewis controls. Pulse-wave velocity (PWV) was recorded under urethane anesthesia (1.3 g/kg ip) in mixed-sex animals aged 6 and 12 wk and in 12-wk-old animals treated with perindopril (3 mg·kg(-1)·day(-1) po) from age 6-12 wk. Tail-cuff systolic pressures were recorded over the treatment period. After PWV measurements, animals were euthanized and the aorta was removed for histomorphological and calcium analysis. Hypertension in LPK at 6 and 12 wk was associated with a shift of the PWV curve upward and to the right, indicating a decrease in aortic compliance, which was significantly reduced by perindopril. LPK demonstrated greater aortic calcification (6 wk: 123 ± 19 vs. 65 ± 7 and 12 wk: 406 ± 6 vs. 67 ± 6 μmol/g, P < 0.001, LPK vs. Lewis, respectively). This was reduced by treatment with perindopril (172 ± 48 μmol/g, 12 wk LPK P < 0.001). Medial cross-sectional area and elastic modulus/wall stress of the aorta were greater in LPK vs. Lewis control animals at 6 and 12 wk of age and showed an age-related increase that was prevented by treatment with perindopril (P < 0.001). Perindopril also ameliorated the degradation of elastin, increase in collagen content, and medial elastocalcinosis seen in 12-wk LPK. Overall, perindopril improved the structural and functional indices of aortic stiffness in the LPK rats, demonstrating a capacity for angiotensin-converting enzyme inhibition to limit vascular remodeling in chronic kidney disease.

Assessment of differences between repeated pulse wave velocity measurements in terms of 'bias' in the extrapolated cardiovascular risk and the classification of aortic stiffness: is a single PWV measurement enough?

Currently, there is no recommendation regarding the minimum number of pulse wave velocity (PWV) measurements to optimize individual's cardiovascular risk (CVR) stratification. The aim of this study was to examine differences between three single consecutive and averaged PWV measurements in terms of the extrapolated CVR and the classification of aortic stiffness as normal. In 60 subjects who referred for CVR assessment, three repeated measurements of blood pressure (BP), heart rate and PWV were performed. The reproducibility was evaluated by the intraclass correlation coefficient (ICC) and mean±s.d. of differences. The absolute differences between single and averaged PWV measurements were classified as: ≤0.25, 0.26-0.49, 0.50-0.99 and ≥1 m s(-1). A difference ≥0.5 m s(-1) (corresponding to 7.5% change in CVR, meta-analysis data from >12 000 subjects) was considered as clinically meaningful; PWV values (single or averaged) were classified as normal according to respective age-corrected normal values (European Network data). Kappa statistic was used to evaluate the agreement between classifications. PWV for the first, second and third measurement was 7.0±1.9, 6.9±1.9, 6.9±2.0 m s(-1), respectively (P=0.319); BP and heart rate did not vary significantly. A good reproducibility between single measurements was observed (ICC>0.94, s.d. ranged between 0.43 and 0.64 m s(-1)). A high percent with difference ≥0.5 m s(-1) was observed between: any pair of the three single PWV measurements (26.6-38.3%); the first or second single measurement and the average of the first and second (18.3%); any single measurement and the average of three measurements (10-20%). In only up to 5% a difference ≥0.5 m s(-1) was observed between the average of three and the average of any two PWV measurements. There was no significant agreement regarding PWV classification as normal between: the first or second measurement and the averaged PWV values. There was significant agreement in classification made by the average of the first two and the average of three PWV measurements (κ=0.85, P<0.001). Even when high reproducibility in PWV measurement is succeeded single measurements provide quite variable results in terms of the extrapolated CVR and the classification of aortic stiffness as normal. The average of two PWV measurements provides similar results with the average of three.