Identifying the high-benefit population for weight management-based cardiovascular disease prevention in Japan

Background

Cardiovascular-disease (CVD) is the leading cause of death, and the association between obesity and CVD is particularly significant among women. Given the evidence highlighting the significance of weight-gain velosity, we aimed to elucidate its influence on cardio-ankle vascular index (CAVI), a reliable surrogate marker of CVD, and identify the high-benefit population where this influence is most pronounced.

Methods

This multicenter retrospective study used electronic data from annual health checkups for workers in Japan. Individuals who voluntarily measured CAVI in 2019 were included, and weight-gain velosity was defined as the mean BMI gain from 2015 to 2019. Our primary outcome was the relationship between weight-gain velosity and CAVI.

Results

Among 459 individuals, 53 had CAVI ≥ 9. Random forest analysis revealed that age was the most important factor, followed by lipid metabolism, weight-gain velosity, and glucose metabolism, with sex being the least important. Non-linear regression analysis of the effect of age on CAVI ≥ 9 showed the effect was pronounced after age 60, and the trend was greater in women. Among individuals aged 60 or younger, the aOR of weight-gain velosity for CAVI ≥ 9 was significantly positive (aOR 11.95, 95 %CI 1.13-126.27), while it was not significant for those older than 60. The relationship between weight-gain velosity and CAVI provides a new perspective on CVD risk factors. The effects of age, especially after 60, and weight-gain velosity in early- to middle-adulthood on arterial stiffness are emphasized.

Conclusions

These findings underscore the importance of weight management under age 60, especially in women.

Relationship of Serum Uric Acid with Kidney Function Decline Mediated by Systemic Arterial Stiffness: A Retrospective Cohort Study in Japan

Hyperuricemia is associated with kidney function decline (KFD), although whether hyperuricemia directly causes nephrotoxicity or is indirectly mediated by systemic arterial stiffening remains unclear. We examined the detailed relationship of serum uric acid (SUA) with KFD and potential mediation by arterial stiffness. Study population was 27,648 urban residents with an estimated glomerular filtration rate (eGFR) of ≥60 mL/min/1.73 m2 at baseline, and they participated in a median of three consecutive annual health examinations. Arterial stiffness was assessed using cardio-ankle vascular index (CAVI). KFD was defined as a decrease in eGFR to below 60. Multivariate analysis showed an association between baseline SUA and CAVI independent of eGFR. During the study period, 6.6% of participants developed KFD. Stratified analysis revealed a linear relationship between the contribution of CAVI or SUA and KFD. ROC analysis determined a cutoff CAVI of 8.0 (males) or 7.9 (females) and a cutoff SUA of 6.3 (males) or 4.5 mg/dL (females) for predicting KFD. The linkage between SUA and CAVI was associated with a greater increase in the hazard ratio for KFD with an increase in SUA. CAVI showed the mediating effect on the relationship of SUA with KFD after an adjustment for confounders. SUA was associated positively with CAVI-mediated KFD. Further studies should verify whether intensive SUA-lowering treatment prevents KFD via improving vascular function.

Effects of Vildagliptin, a Dipeptidyl Peptidase-4 Inhibitor, on the Parameters of Glucose Metabolism and the Cardio-Ankle Vascular Index in Individuals with Type 2 Diabetes

DPP-4 inhibitors are frequently used as first-line agents for the treatment of type 2 diabetes in Japan. This study aimed to examine the effects of vildagliptin on glucose metabolism and arterial stiffness. Twenty treatment-naïve patients with type 2 diabetes (8 males and 12 females) received vildagliptin 50 mg twice daily for 6 months. Self-monitored blood glucose measurements and a 75 g OGTT were performed. Arterial stiffness was assessed using the CAVI. After the vildagliptin treatment, a significant decrease in the median HbA1c (from 8.3 to 6.4%) and fasting HOMA-β (from 26.1 to 34.5%), and a marginally significant decrease in the CAVI (from 8.9 to 8.4, p = 0.087) were observed. The glycemic variability parameters also improved, whereas the insulin sensitivity and oxidative stress remained unchanged. Participants with a lower glycemic variability on the 75 g OGTT after vildagliptin treatment showed a significant decrease in their CAVI. The baseline BMI was significantly higher for the participants with a decreased CAVI than in those with no change in their CAVI (24.5 vs. 20.8 kg/m2). After vildagliptin treatment, a decrease in the CAVI was observed, especially in the individuals with improved glycemic variability on the 75 g OGTT. Vildagliptin may be suitable for vascular protection in individuals with high glycemic variability and/or an elevated BMI.

Elevated Serum Cystatin C and Decreased Cathepsin S/Cystatin C Ratio Are Associated with Severe Peripheral Arterial Disease and Polyvascular Involvement

Peripheral arterial disease (PAD) is frequently associated with atherosclerotic manifestations of the carotids and coronaries. Polyvascular involvement and low ankle−brachial index predict major cardiovascular events and high mortality. Cathepsin S (Cat S) promotes the inflammatory pathways of the arterial wall, while Cystatin C (Cys C) functions as its inhibitor; therefore, Cys C was proposed to be a biomarker of progression in PAD. In a single-center observational study, we investigated the correlations of serum Cys C and Cat S/Cys C ratio in a group of 90 PAD patients, predominantly with polyvascular involvement. Cys C and Cat S/Cys C were associated with ankle−brachial index (ABI) scores <0.4 in univariate and multiple regression models. Furthermore, both markers correlated positively with the plasma Von Willebrand Factor Antigen (VWF: Ag) and Von Willebrand Factor collagen-binding activity (VWF: CB). In addition, Cat S/Cys C was significantly decreased, whereas Cys C increased in subjects with three-bed atherosclerotic involvement. According to our results, high serum Cys C and low Cat S/Cys C ratios may indicate severe peripheral arterial disease and polyvascular atherosclerotic involvement.

The Role of Cardio-Ankle Vascular Index as a Predictor of Mortality in Patients on Maintenance Hemodialysis

Aim

Mortality rate of maintenance hemodialysis patients is known to be high. Cardio-ankle vascular index (CAVI) is an index reflecting the proper stiffness of the arterial tree from the origin of the aorta to the ankle. We aimed to clarify the utility of CAVI as a predictor of mortality in hemodialysis patients. The roles of age and nutritional conditions on survival were also examined.

Methods

We followed 242 patients undergoing hemodialysis for 6 consecutive years. Data from 209 patients (mean age was 60 ± 11 years) excluding those with ankle-brachial index <0.90 were then analyzed. CAVI and heart to ankle pulse wave velocity (haPWV) were measured using Vasera 1500.

Results

Thirty-eight hemodialysis patients who died during the 6-year period had higher age, cardiothoracic ratio (CTR), CAVI, and haPWV, and lower diastolic blood pressure, albumin, phosphate, and calcium phosphate product. The Kaplan–Meier curves for cumulative survival among the tertile groups showed that the mortality rate was higher in the highest tertile (T3) compared to T1/T2 for both CAVI and haPWV. Receiver operating characteristic (ROC) analysis revealed that CAVI had better discriminatory power for all-cause mortality compared to haPWV. In the Cox-proportional hazards analyses, 1 SD increase in both parameters contributed independently to all-cause mortality [CAVI: HR 1.595 (95% CI 1.108–2.297), haPWV: HR 1.695 (95% CI 1.185–2.425)], as well as age and CTR. Both parameters above the cut-offs estimated in the ROC analysis (CAVI ≥ 9.2, haPWV ≥ 8.9) also had independent contributions to mortality.

Conclusion

Through the 6 consecutive years of follow-up in 209 HD patients, increased CAVI might represent a major modifiable risk factor for all-cause mortality. Further research is needed to examine whether CAVI-lowering interventions contribute to improved prognosis.

Enhanced prediction of renal function decline by replacing waist circumference with "A Body Shape Index (ABSI)" in diagnosing metabolic syndrome: a retrospective cohort study in Japan

Background

Abdominal obesity as a risk factor for diagnosing metabolic syndrome (MetS) is conventionally evaluated using waist circumference (WC), although WC does not necessarily reflect visceral adiposity.

Objective

To examine whether replacing WC with “A Body Shape Index (ABSI)”, an abdominal obesity index calculated by dividing WC by an allometric regression of weight and height, in MetS diagnosis is useful for predicting renal function decline.

Subjects/Methods

In total, 5438 Japanese urban residents (median age 48 years) who participated in a public health screening program for 4 consecutive years were enrolled. Systemic arterial stiffness was assessed by cardio-ankle vascular index (CAVI). The predictability of the new-onset renal function decline (eGFR < 60 mL/min/1.73 m²) by replacing high WC with high ABSI (ABSI ≥ 0.080) was examined using three sets of MetS diagnostic criteria: Japanese, IDF and NCEP-ATPIII.

Results

In Japanese and NCEP-ATPIII criteria, MetS diagnosed using ABSI (ABSI-MetS) was associated with significantly higher age-adjusted CAVI compared to non-MetS, whereas MetS diagnosed using WC (WC-MetS) showed no association. Kaplan–Meier analysis of the rate of new-onset renal function decline over 4 years (total 8.7%) showed remarkable higher rate in subjects with ABSI-MetS than in those without (log-rank test p < 0.001), but almost no difference between subjects with and without WC-MetS (p = 0.014–0.617). In gender-specific Cox-proportional hazards analyses including age, proteinuria, and treatments of metabolic disorders as confounders, ABSI-MetS (Japanese criteria for both sexes, IDF criteria for men) contributed independently to the new-onset renal function decline. Of these, the contribution of IDF ABSI-MetS disappeared after adjustment by high CAVI in the subsequent analysis.

Conclusion

In this study, replacing WC with ABSI in MetS diagnostic criteria more efficiently predicted subjects at risk of renal function decline and arterial stiffening.

Cardio-ankle vascular index with renal progression and mortality in high atherosclerosis risk: a prospective cohort study in CORE-Thailand

BACKGROUND

Increased arterial stiffness is linked to markers of endothelial dysfunction and vasculopathy such as albuminuria, vascular calcification, left ventricular hypertrophy and cardiovascular (CV) diseases. Studies of arterial stiffness on renal progression are limited.

OBJECTIVE

The study aimed to evaluate the association between high cardio-ankle vascular index (CAVI) and renal endpoint and all-cause mortality in a Thai population with high atherosclerosis risk.

METHODS

A multicenter prospective cohort study was conducted among subjects with high CV risk or established CV diseases in Thailand. Subjects were divided into 3 groups with mean CAVI < 8, 8-8.9, and ≥ 9, respectively. Primary composite outcome consisted of estimated glomerular filtration rate (eGFR) decline over 40%, eGFR less than 15 mL/min/1.73 m², doubling of serum creatinine, initiation of dialysis and death related to renal causes. The secondary outcomes were all-cause mortality, CV mortality and eGFR decline.

RESULTS

A total of 4898 subjects (2743 men and 2155 women) were enrolled. Cox proportional hazards model showed a significant relationship of high CAVI (CAVI ≥ 9) and primary composite outcome. Subjects with high CAVI at baseline had a 1.45-fold (95% CI 1.13-1.84) significant risk for the primary composite outcome and 1.72-fold (95% CI 1.12-2.63) risk for all-cause mortality, compared with normal CAVI (CAVI < 8). After stepwise multivariate analysis, the high CAVI group was only positively associated with primary composite outcome. Kaplan-Meier curve of the primary composite outcome and all-cause mortality demonstrated the worst survival in the high CAVI group (log-rank test with P < 0.05).

CONCLUSION

In a Thai cohort with high atherosclerosis risk, increased arterial stiffness was a risk factor for worsening renal function, including end-stage renal disease and initiation of dialysis.

Arterial stiffness in health and disease: The role of cardio-ankle vascular index

Arterial stiffness increases with age, as well as in various pathological states, including obesity, diabetes mellitus, smoking, and dyslipidemia, and it has important consequences for cardiovascular health. Arterial stiffness plays a central role in hemodynamic dysfunction characterized by excess pulsatility; specifically, it leads to heart failure, cerebrovascular disease, and renal failure. Among measures of arterial stiffness, carotid-femoral pulse wave velocity is considered as the reference standard; however, it has not been incorporated into routine clinical practice. Cardio-ankle vascular index (CAVI), which is a marker of arterial stiffness measured from the origin of the aorta to the ankle, was developed in 2004. CAVI is based on stiffness parameter β, which is theoretically independent of blood pressure at the time of measurement. CAVI applies stiffness parameter β to arterial segments between the heart and ankle. The measurement of CAVI is simple and well-standardized, and its reproducibility and accuracy are acceptable. Several studies have demonstrated that CAVI is high in patients with various atherosclerotic risk factors, and treatment of cardiovascular risk factors and lifestyle modifications improve CAVI. Several prospective studies have investigated the association between CAVI and future cardiovascular events in the general population and in patients with cardiovascular risk factors. A cut-off value of 9.0 is proposed for predicting patients at a high risk of cardiovascular events. From this review, it is clear that CAVI may be useful in the prevention of cardiovascular disease.

Rapid Rise of Cardio-Ankle Vascular Index May Be a Trigger of Cerebro-Cardiovascular Events: Proposal of Smooth Muscle Cell Contraction Theory for Plaque Rupture

Cardiovascular diseases have been recognized as the main cause of death all over the world. Recently, the established cardio-ankle vascular index (CAVI) has become known as an index of arterial stiffness of the arterial tree from the origin of the aorta to the ankle. CAVI reflects the progress of arteriosclerosis, and a rapid rise in CAVI indicates arterial smooth muscle cell contraction. Considering the vasculature of the atheroma where vasa vasorum penetrates the smooth muscle cell layer and supplies blood to the intimal atheromatous lesion, a rapid rise of CAVI means “choked” atheroma. Thus, we proposed a “smooth muscle cell contraction” hypothesis of plaque rupture.

Elevated cardio-ankle vascular index may be related to future stroke risk in Japanese subjects

BACKGROUND

The cardio-ankle vascular index (CAVI) has been proposed as a useful parameter for arteriosclerotic diseases. However, whether it is associated with stroke risk in Japanese subjects remains unclear.

METHODS

In total, 280 Japanese subjects (92 females, 52.6 ± 5 years old) underwent a medical check-up. CAVI value and risk factors for arterial dysfunction were evaluated; the predicted 10-year stroke risk was measured by the Japan Public Health Center study.

RESULTS

Age, sex, body mass index, and systolic blood pressure were significant independent predictors of CAVI. CAVI values were significantly elevated in the high, compared with the medium-low and low predicted risk groups. A significant odds ratio (OR) for the high-risk group was noted in the highest quartile of CAVI values (OR, 14.67; 95% confidence interval [CI], 3.17-68.0), compared with the lowest quartile, after adjusting for potential confounders. A significant OR for very high predicted stroke risk was also found for each quartile increase (OR, 3.04; 95% CI, 1.87-4.94) and 1-standard deviation increase (OR, 2.24; 95% CI, 1.52-3.30) in CAVI value.

CONCLUSION

Elevated CAVI values were related to an elevated predicted stroke risk, suggesting that CAVI could be a suitable surrogate marker for finding subjects at an increased risk of first-ever stroke.

New Horizons of Arterial Stiffness Developed Using Cardio-Ankle Vascular Index (CAVI)

Arterial stiffness is recognized mainly as an indicator of arteriosclerosis and a predictor of cardiovascular events. Cardio-ankle vascular index (CAVI), which reflects arterial stiffness from the origin of the aorta to the ankle, was developed in 2004. An important feature of this index is the independency from blood pressure at the time of measurement. A large volume of clinical evidence obtained using CAVI has been reported. CAVI is high in patients with various atherosclerotic diseases including coronary artery disease and chronic kidney disease. Most coronary risk factors increase CAVI and their improvement reduces CAVI. Many prospective studies have investigated the association between CAVI and future cardiovascular disease (CVD), and proposed CAVI of 9 as the optimal cut-off value for predicting CVD. Research also shows that CAVI reflects afterload and left ventricular diastolic dysfunction in patients with heart failure. Furthermore, relatively acute changes in CAVI are observed under various pathophysiological conditions including mental stress, septic shock and congestive heart failure, and in pharmacological studies. CAVI seems to reflect not only structural stiffness but also functional stiffness involved in acute vascular functions. In 2016, Spronck and colleagues proposed a variant index CAVI₀, and claimed that CAVI₀ was truly independent of blood pressure while CAVI was not. This argument was settled, and the independence of CAVI from blood pressure was reaffirmed. In this review, we summarize the recently accumulated evidence of CAVI, focusing on the proposed cut-off values for CVD events, and suggest the development of new horizons of vascular function index using CAVI.

Marker Of Sepsis Severity Is Associated With The Variation In Cardio-Ankle Vascular Index (CAVI) During Sepsis Treatment

Introduction

The main pathophysiology of sepsis is considered to be circulation crisis with an imbalance of vasodilation and vasoconstriction mechanisms, which contributes to multiple organ failure. However, sepsis-induced hemodynamic changes have not been fully validated by novel arterial stiffness parameter. The aim of this study was to clarify the acute vascular alteration and hemodynamic change in sepsis using cardio-ankle-vascular index (CAVI).

Methods

Twenty-one Japanese patients (14 males and 7 females, age 62.8 ± 19.0 years) with sepsis were recruited. CAVI was measured before and 1-week after sepsis treatment.

Results

The leading underlying cause of sepsis was pyelonephritis, followed by pneumonia, lung abscess, hepatic abscess and cholecystitis. All subjects recovered from sepsis. Analysis of all subjects showed a significant increase in CAVI after 1-week treatment (7.9 ± 2.4 to 9.6 ± 1.8, P < 0.001), but no significant change in blood pressure (BP) was observed. Significant correlations were observed for all combinations among the change in CAVI, systolic BP and ln[procalcitonin (PCT)], respectively. Additionally, in subjects with PCT at presentation ≥2.0 ng/mL, the increase in CAVI after treatment was significantly greater compared to those with PCT < 2.0 ng/mL (2.4 ± 1.6 vs 1.1 ± 0.9, P = 0.037).

Discussion

CAVI may reflect sepsis-induced vascular alteration which is not indicated by BP change, and is associated with sepsis severity. These findings suggest the usefulness of CAVI in the management of circulatory failure in sepsis patients.

Coefficients in the CAVI Equation and the Comparison Between CAVI With and Without the Coefficients Using Clinical Data

Aim: The Cardio-Ankle Vascular Index (CAVI) is a stiffness index of the arterial tree from the origin of the aorta to the ankle, independent of blood pressure at the time of measurement. The CAVI equation includes the coefficients “a” and “b” to adjust it to the value of Hasegawa's pulse wave velocity, which is compensated for at 80 mmHg of diastolic pressure. To verify this adjustment with the coefficients, the clinical significance of CAVI and CAVI without the coefficients (haβ) were compared in both an epidemiological study and an acute clinical study.

Methods: In the epidemiological study, the significances of CAVI and haβ among people with or without coronary risks such as hypertension, dyslipidemia, hyperglycemia, and abnormal electrocardiography change, were compared. In the acute clinical study, nitroglycerin was administered to subjects in a control group and to coronary artery disease patients, observing CAVI and haβ values over a 20-min period.

Results: There was no discrepancy in terms of statistically significant differences between CAVI and haβ among subjects with or without risk factors. Furthermore, there was also no discrepancy in terms of statistically significant differences between CAVI and haβ during the changes of those values following nitroglycerin administration over a 20-min period.

Conclusion: In both the epidemiologic and clinical studies, there was no discrepancy in terms of significant differences between CAVI and haβ. These results suggest that both are valid as indices of stiffness of the arterial tree from the origin of the aorta to the ankle.

Lipid Parameters are Independently Associated with Cardio-Ankle Vascular Index (CAVI) in Healthy Japanese Subjects

AIM

To investigate the associations of conventional lipid parameters with arterial stiffness assessed by cardio-ankle vascular index (CAVI).

METHODS

A retrospective cross-sectional study was conducted in 23,257 healthy Japanese subjects (12,729 men and 10,528 women, aged 47.1±12.5 years, body mass index (BMI) 22.9±3.4 kg/m2) who underwent health screening between 2004 and 2006 in Japan.

RESULTS

Male subjects had significantly higher BMI, CAVI and triglycerides (TG), and lower high-density lipoprotein cholesterol (HDL-C) compared to female subjects. After adjusting for confounders, including gender, age, systolic blood pressure and BMI identified by multiple regression analysis, adjusted CAVI was lower in normolipidemic than in dyslipidemic subjects. Among dyslipidemic subjects, those with hypertriglyceridemia had higher adjusted CAVI. A trend test detected linear relations between adjusted CAVI and all the conventional lipid parameters throughout the entire range of serum levels. After adjusting for confounders, logistic regression models showed that all lipid parameters contributed independently to high CAVI (≥90th percentile). Receiver-operating-characteristic analysis determined reliable cut-off values of 93 mg/dl for TG (area under the curve, AUC= 0.735), 114 mg/dl for low-density lipoprotein cholesterol (AUC=0.614) and 63 mg/dl for HDL-C (AUC=0.728) in predicting high CAVI. These cut-off values were confirmed to independently predict high CAVI in a bivariate logistic regression model.

CONCLUSION

The present study demonstrated independent contribution of conventional lipid parameters to CAVI, indicating a possible association of lipid parameters with early vascular damage.

In healthy normotensive subjects age and blood pressure better predict subclinical vascular and cardiac organ damage than atherosclerosis biomarkers

PURPOSE

Only few studies evaluated biomarkers useful for defining the cardiovascular risk of a subject in a pre-clinical condition (i.e. healthy subjects). In this context we sought to determine the relationships of Plasminogen activator inhibitor type 1 (PAI-1), P-Selectin, Tissue Inhibitors Metalloproteinases type 1 (TIMP-1) and Cystatin-C with subclinical Target Organ Damage (TOD) in normotensive and normoglycemic subjects without known cardiovascular and kidney diseases.

MATERIALS AND METHODS

480 blood donors participated at the present analysis. TOD was evaluated as Pulse Wave Velocity (PWV), Left Ventricular Hypertrophy (LVH) and Intima Media Thickness (IMT) and carotid plaque presence) grouped together under carotid TOD.

RESULTS

3.1% of the subjects showed a PWV higher than 10 m/sec with those subjects exerting significantly lower values of P-Selectine (0.068 ± 0.015 vs 0.08 ± 0.036 mg/L, p = .014). 8.8% of the subjects showed carotid TOD that was associated with higher Cystatin-C values (0.67 ± 0.17 vs 0.63 ± 0.14 mg/L, p = .045). Finally 23.8% of the subjects showed LVH with no significant differences regarding biomarkers. Despite some significant correlations between biomarkers and TOD, at the multivariate analysis none came out to be as significant predictor of the assessed TOD.

CONCLUSIONS

in normotensive and normoglycemic healthy subjects, the evaluated biomarkers of atherosclerotic process didn't show any significant association with cardiac, carotid and vascular TOD while age and BP are its principal predictors.

Protocol for Evaluating the Cardio-Ankle Vascular Index to Predict Cardiovascular Events in Japan: A Prospective Multicenter Cohort Study

INTRODUCTION

The cardio-ankle vascular index (CAVI) was developed in Japan and is a blood pressure-independent index of arterial stiffness from the origin of the aorta to the ankle. In recent years, it has been studied by many researchers worldwide, and it is strongly anticipated that it will play a role as a predictive factor for arteriosclerotic diseases. The objective of this study was to examine the benefits of using CAVI as a predictor of cardiovascular events in high-risk patients.

METHODS AND DESIGN

This prospective multicenter study to evaluate the usefulness of the CAVI to predict cardiovascular events in Japan (CAVI-J) is a cohort study with central registration. Participants (n = 3,000) will be scheduled to enroll and data will be collected for up to 5 years from entry of participants into the study. To be eligible to participate in the CAVI-J study, individuals have to be aged between 40 and 74 years and have at least one of the following risk factors for arteriosclerosis: (1) type 2 diabetes mellitus; (2) high-risk hypertension; (3) metabolic syndrome; (4) chronic kidney disease (stage 3), or (5) history of coronary artery disease or noncardiogenic cerebral infarction. The primary endpoints of this study are cardiovascular death, nonfatal myocardial infarction, and stroke. The secondary endpoints are composite cardiovascular events including all cause death, angina pectoris with revascularization, new incidence of peripheral artery disease, abdominal aortic aneurysm, aortic dissection, heart failure requiring hospitalization, and deterioration in renal function. The cutoff for CAVI against the incidence of cardiovascular events will be determined.

Inverse relationship of cardioankle vascular index with BMI in healthy Japanese subjects: a cross-sectional study

Objective

The objective of this study is to investigate the association of body mass index (BMI) with arterial stiffness assessed by cardioankle vascular index (CAVI).

Subjects and methods

A retrospective cross-sectional study was conducted in 23,257 healthy Japanese subjects (12,729 men and 10,528 women, aged 47.1 ± 12.5 years, BMI 22.9 ± 3.4 kg/m²) who underwent health screening between 2004 and 2006 in Japan. Exclusion criteria were current medication use and a past history of cardiovascular disease, hypertension, stroke, diabetes, and nephritis.

Results

Male subjects showed significantly higher BMI, CAVI, and triglycerides and lower high-density lipoprotein (HDL)-cholesterol compared with female subjects. Next, the subjects were divided into tertiles of BMI: lower, middle, and upper, in a gender-specific manner. After adjusting for confounders including age, systolic blood pressure, and HDL-cholesterol identified by multiple regression analysis, the mean CAVI decreased progressively as BMI tertile increased in both genders. Furthermore, a negative inverse relationship between BMI and adjusted CAVI was observed throughout the BMI distribution. Multivariate logistic regression model for contributors of high CAVI (≥90th percentile) identified obesity (odds ratios (95% confidence interval): 0.804 (0.720–0.899)], older age [15.6 (14.0–17.4)], male gender [2.26 (2.03–2.51)], hypertension [2.28 (2.06–2.54)], impaired fasting glucose [1.17 (1.01–1.37)], and low HDL-cholesterol [0.843 (0.669–1.06)] as independent factors.

Conclusion

We demonstrated an inverse relationship between CAVI and BMI in healthy Japanese subjects, suggesting that systemic accumulation of adipose tissue per se may lead to a linear decrease of arterial stiffness in nonobese and obese subjects without metabolic disorders.

Subclinical cardiovascular disease markers and vitamin D deficiency in non-dialysis chronic kidney disease patients

INTRODUCTION

Since 25-hydroxyvitamin D (25(OH)D) deficiency has been linked to an increased risk for cardiovascular disease (CVD) in the hemodialysis population, we aimed to determine the relationship between serum 25(OH)D level and markers of subclinical CVD in non-dialysis chronic kidney disease (CKD) patients.

MATERIAL AND METHODS

This cross-sectional, single-center study prospectively enrolled 87 clinically stable CKD patients (median age: 61 (57-66) years, 51% male, median estimated glomerular filtration rate (eGFR): 32 (27-37) ml/min). Five markers of subclinical CVD were assessed: intima-media thickness, abdominal aortic calcifications (AAC) using the Kauppila score, cardio-ankle vascular index, ankle-brachial index (ABI) and interventricular septum thickness.

RESULTS

Vascular (37%), glomerular (23%) and interstitial (18%) nephropathies were the main causes of CKD. 25(OH)D had a median value of 14 (12.5-17.1) ng/ml, and its levels decreased with eGFR (rs = 0.19; p = 0.04). Patients with 25(OH)D deficiency (54%) were older, had a higher serum alkaline phosphatase level, lower ABI and higher AAC score. There were no differences between the two groups regarding other traditional or non-traditional risk factors for atherosclerosis. The association between subclinical CVD markers and 25(OH)D was further evaluated in multivariable binomial logistic regression models adjusted for CV risk factors. Lower 25(OH)D level was retained as an independent predictor only for pathological ABI.

CONCLUSIONS

This is the first study to evaluate the relationship between a large set of subclinical CVD markers and 25(OH)D deficiency in non-dialysis CKD patients. We found that hypovitaminosis D is associated with subclinical peripheral arterial disease, independently of other cardiovascular risk factors.

Effect of nitroglycerin administration on cardio-ankle vascular index

Purpose

The purpose of this study was to clarify the difference between effects of nitroglycerin (NTG) on the functional stiffness in patients with and without coronary artery disease (CAD) using a newly developed stiffness index, cardio-ankle vascular index (CAVI).

Subjects and methods

The two subject groups in this study were normal controls (n=31) and CAD patients (n=25). The normal controls had no medical history and were not on regular medications. On the other hand, the CAD patients had received various treatments like antihypertensive drugs, hypoglycemic agents, and statins. This study was conducted in CAD patients under medications. After a single sublingual administration of NTG 0.3 mg, CAVI, blood pressure (BP), and heart rate (HR) were measured every 5 minutes for 20 minutes. Comparisons of each parameter before and after taking NTG were evaluated for statistical significance using analysis of variance and post hoc tests. Tukey–Kramer test was used for post hoc comparisons.

Results

In the normal controls, CAVI significantly decreased from baseline after 5, 10, and 15 minutes (from 6.5±0.9 to 5.2±0.9, 5.5±0.9, and 5.7±0.9, respectively). Systolic BP and HR were not significantly changed. Diastolic BP significantly decreased from baseline after 5 and 10 minutes (from 72±8 to 64±9 and 63±9 mmHg, respectively). On the other hand, CAVI, HR, and diastolic BP were not changed significantly in CAD patients. Systolic BP was significantly decreased from baseline after 5, 10, and 15 minutes (from 147±16 to 131±14, 129±12, and 129±13 mmHg, respectively). In the comparison of the two groups, ΔCAVI was not significantly different between the normal controls and CAD patients (−1.4±0.7 vs −1.4±0.9, −1.1±0.7 vs −1.4±1.0, −0.8±0.7 vs −1.2±1.0, and −0.5±0.7 vs −1.1±1.0 at 5, 10, 15, and 20 minutes, respectively). ΔHR was not significantly different between the two groups. ΔSystolic BP in the CAD patients was significantly higher than in the normal controls at 5, 10, 15, and 20 minutes (normal controls vs CAD; −3±7 vs −10±11, −3±5 vs −10±11, −3±6 vs −13±10, and −1±6 vs −11±10 mmHg, respectively). ΔDiastolic BP in the normal controls was significantly higher than in the CAD patients at 5 and 10 minutes (normal controls vs CAD; −8±6 vs −4±4 and −9±4 vs −6±5 mmHg, respectively).

Conclusion

After NTG administration, the stiffness of the arteries from the origin of the aorta to the ankle as measured by CAVI decreased in both the normal controls and CAD patients, indicating that the response of arterial smooth muscle cells to nitric oxide is preserved even in CAD patients under medication.

Clinical assessment of arterial stiffness with cardio-ankle vascular index: theory and applications

Arterial stiffness is often assessed in clinical medicine, because it is not only an important factor in the pathophysiology of blood circulation but also a marker for the diagnosis and the prognosis of cardiovascular diseases. Many parameters have so far been proposed to quantitatively represent arterial stiffness and distensibility, such as pressure-strain elastic modulus (Ep), stiffness parameter (β), pulse wave velocity (PWV), and vascular compliance (Cv). Among these, PWV has been most frequently applied to clinical medicine. However, this is dependent on blood pressure at the time of measurement, and therefore it is not appropriate as a parameter for the clinical evaluation of arterial stiffness, especially for the studies on hypertension. On the contrary, stiffness parameter β is an index reflecting arterial stiffness without the influence of blood pressure. Recently, this parameter has been applied to develop a new arterial stiffness index called cardio-ankle vascular index (CAVI). Although this index is obtained from the PWV between the heart and the ankle, it is essentially similar to the stiffness parameter β, and therefore it does not depend on blood pressure changes during the measurements. CAVI is being extensively used in clinical medicine as a measure for the evaluation of cardiovascular diseases and risk factors related to arteriosclerosis. In the present article, we will explain the theoretical background of stiffness parameter β and the process to obtain CAVI. And then, the clinical utility of CAVI will be overviewed by reference to recent studies.

Assessment of Arterial Stiffness Using the Cardio-Ankle Vascular Index

BACKGROUND

Arterial stiffness is an independent predictor of outcomes for patients with cardiovascular disease. Although measurement of pulse wave velocity is a widely accepted, noninvasive approach for the assessment of arterial stiffness, its accuracy is affected by changes in blood pressure.

SUMMARY

The cardio-ankle vascular index (CAVI) is an index of the overall stiffness of the artery from the origin of the aorta to the ankle and is theoretically independent of blood pressure at the time of measurement. CAVI increases linearly with age and is elevated even in mild arteriosclerotic disease. It can identify differences in the degree of arteriosclerosis among patients with severe arteriosclerotic disease and better reflects the severity of disease of the coronary artery than does brachial-ankle pulse wave velocity. Patients with higher CAVI values show a poor prognosis compared with those with lower CAVI values. Furthermore, CAVI can be lowered by controlling diabetes mellitus and hypertension.

KEY MESSAGES

The primary aims of assessing arterial stiffness using CAVI are to assist in the early detection of arteriosclerosis, allowing timely treatment and lifestyle modification, and to quantitatively evaluate the progression of disease and the effectiveness of treatment. Whether CAVI-guided therapy can improve prognosis in high-risk patients needs to be further examined to confirm the clinical usefulness of this measure.

The Role of Monitoring Arterial Stiffness with Cardio-Ankle Vascular Index in the Control of Lifestyle-Related Diseases

Arteriosclerosis is a major contributor to cardiovascular diseases. One of the difficulties in controlling those diseases is the lack of a suitable indicator of arteriosclerosis or arterial injury in routine clinical practice. Arterial stiffness was supposed to be one of the monitoring indexes of arteriosclerosis. Cardio-ankle vascular index (CAVI) is reflecting the stiffness of the arterial tree from the origin of the aorta to the ankle, and one of the features of CAVI is independency from blood pressure at a measuring time. When doxazosin, an α1-adrenergic blocker, was administered, CAVI decreased, indicating that arterial stiffness is composed of both organic stiffness and functional stiffness, which reflects the contraction of arterial smooth muscle. CAVI shows a high value with aging and in many arteriosclerotic diseases, and is also high in persons possessing main coronary risk factors such as diabetes mellitus, metabolic syndrome, hypertension and smoking. Furthermore, when the most of those risk factors were controlled by proper methods, CAVI improved. Furthermore, the co-relationship between CAVI and heart function was demonstrated during treatment of heart failure. This paper reviews the principle and rationale of CAVI, and discusses the meaning of monitoring CAVI in following up so-called lifestyle-related diseases and cardiac dysfunction in routine clinical practice.

Cardio-ankle vascular index is associated with cardiovascular target organ damage and vascular structure and function in patients with diabetes or metabolic syndrome, LOD-DIABETES study: a case series report

Background

The cardio ankle vascular index (CAVI) is a new index of the overall stiffness of the artery from the origin of the aorta to the ankle. This index can estimate the risk of atherosclerosis. We aimed to find the relationship between CAVI and target organ damage (TOD), vascular structure and function, and cardiovascular risk factors in Caucasian patients with type 2 diabetes mellitus or metabolic syndrome.

Methods

We included 110 subjects from the LOD-Diabetes study, whose mean age was 61 ± 11 years, and 37.3% were women. Measurements of CAVI, brachial ankle pulse wave velocity (ba-PWV), and ankle brachial index (ABI) were taken using the VaSera device. Cardiovascular risk factors, renal function by creatinine, glomerular filtration rate, and albumin creatinine index were also obtained, as well as cardiac TOD with ECG and vascular TOD and carotid intima media thickness (IMT), carotid femoral PWV (cf-PWV), and the central and peripheral augmentation index (CAIx and PAIx). The Framingham-D’Agostino scale was used to measure cardiovascular risk.

Results

Mean CAVI was 8.7 ± 1.3. More than half (54%) of the participants showed one or more TOD (10% cardiac, 13% renal; 48% vascular), and 13% had ba-PWV ≥ 17.5 m/s. Patients with any TOD had the highest CAVI values: 1.15 (CI 95% 0.70 to 1.61, p < 0.001) and 1.14 (CI 95% 0.68 to 1.60, p < 0.001) when vascular TOD was presented, and 1.30 (CI 95% 0.51 to 2.10, p = 0.002) for the cardiac TOD. The CAVI values had a positive correlation with HbA1c and systolic and diastolic blood pressure, and a negative correlation with waist circumference and body mass index. The positive correlations of CAVI with IMT (β = 0.29; p < 0.01), cf-PWV (β = 0.83; p < 0.01), ba-PWV (β = 2.12; p < 0.01), CAIx (β = 3.42; p < 0.01), and PAIx (β = 5.05; p = 0.04) remained after adjustment for cardiovascular risk, body mass index, and antihypertensive, lipid-lowering, and antidiabetic drugs.

Conclusions

The results of this study suggest that the CAVI is positively associated with IMT, cf-PWV, ba-PWV, CAIx, and PAIx, regardless of cardiovascular risk and the drug treatment used. Patients with cardiovascular TOD have higher values of CAVI.

Trial registration

Clinical Trials.gov Identifier: NCT01065155

Comparison of cystatin C- and creatinine-based estimated glomerular filtration rate to predict coronary heart disease risk in Japanese patients with obesity and diabetes

The aim of this study is to determine which indicator of chronic kidney disease most closely correlates with 10-year Framingham coronary heart disease (CHD) risk among serum creatinine, serum cystatin C (S-CysC), urine albumin-creatinine ratio (UACR), estimated creatinine-based GFRs (eGFRcre), and estimated CysC-based GFRs (eGFRcys) in patients with obesity and diabetes. Serum creatinine, S-CysC, UACR, and cardio-ankle vascular index (CAVI) were examined in 468 outpatients with obesity and type 2 diabetes, free of severe renal dysfunction or previous history of cardiovascular disease, as a cross-sectional survey using baseline data from the multi-centered Japan Diabetes and Obesity Study. S-CysC and eGFRcys had significantly stronger correlations with the 10-year Framingham CHD risk than serum creatinine, eGFRcre, and UACR (creatinine, ρ = 0.318; S-CysC, ρ = 0.497; UACR, ρ = 0.174; eGFRcre, ρ = -0.291; eGFRcys, ρ = -0.521; P < 0.01 by Fisher's z-test). S-CysC and eGFRcys had significantly stronger correlations with CAVI than serum creatinine, eGFRcre, and UACR (creatinine, ρ = 0.198; S-CysC, ρ = 0.383; UACR, ρ = 0.183; eGFRcre, ρ = -0.302; eGFRcys, ρ = -0.444; P < 0.05 by Fisher's z-test). The receiver operating characteristic curves to distinguish the high-risk patients for CHD revealed significantly larger areas under the curve of S-CysC and eGFRcys than those of serum creatinine, UACR, and eGFRcre (serum creatinine, 0.64; S-CysC, 0.75; UACR, 0.56; eGFRcre, 0.63; eGFRcys, 0.76; P < 0.01). The data suggested that eGFRcys can be more predictive of the 10-year CHD risk than eGFRcre in Japanese patients with obesity and diabetes.

Factors affecting high-sensitivity cardiac troponin T elevation in Japanese metabolic syndrome patients

PURPOSE

The blood concentration of cardiac troponin T (ie, high-sensitivity cardiac troponin T [hs-cTnT]), measured using a highly sensitive assay, represents a useful biomarker for evaluating the pathogenesis of heart failure or predicting cardiovascular events. However, little is known about the clinical significance of hs-cTnT in metabolic syndrome. The aim of this study was to examine the factors affecting hs-cTnT elevation in Japanese metabolic syndrome patients.

PATIENTS AND METHODS

We enrolled 258 metabolic syndrome patients who were middle-aged males without a history of cardiovascular events. We examined relationships between hs-cTnT and various clinical parameters, including diagnostic parameters of metabolic syndrome.

RESULTS

There were no significant correlations between hs-cTnT and diagnostic parameters of metabolic syndrome. However, hs-cTnT was significantly correlated with age (P<0.01), blood concentrations of brain natriuretic peptide (P<0.01), reactive oxygen metabolites (markers of oxidative stress, P<0.001), and the cardio-ankle vascular index (marker of arterial function, P<0.01). Furthermore, multiple regression analysis revealed that these factors were independent variables for hs-cTnT as a subordinate factor.

CONCLUSION

The findings of this study indicate that in vivo oxidative stress and abnormality of arterial function are closely associated with an increase in hs-cTnT concentrations in Japanese metabolic syndrome patients.

Serum osteoprotegerin is associated with arterial stiffness assessed according to the cardio-ankle vascular index in hypertensive patients

AIM

Arterial stiffness is recognized to be an independent risk factor for cardiovascular morbidity and mortality. Recent studies have found that osteoprotegerin (OPG) is associated with increased pulse wave velocity and may reflect endothelial dysfunction. The aim of this study was to evaluate the relationship between the serum OPG level and arterial stiffness in hypertensive patients using the cardio-ankle vascular index (CAVI).

METHODS

Fasting blood samples were obtained from 115 hypertensive patients and 52 healthy participants. The CAVI value was derived using the waveform device (CAVI-VaSera VS-1000). The serum OPG levels were measured using a commercially available enzyme-linked immunosorbent assay. A CAVI value of ≥9 defined the high arterial stiffness group.

RESULTS

Sixty-five hypertensive patients (56.5%) were included in the high arterial stiffness group. Diabetes (p=0.032), smoking (p=0.044), age (p < 0.001), systolic blood pressure (p=0.001), diastolic blood pressure (p=0.024), pulse pressure (p=0.046) and the creatinine (p=0.013) and serum OPG (p < 0.001) levels were higher in the high arterial stiffness group than in the low arterial stiffness group, while the glomerular filtration rate (p=0.003) was lower in the high arterial stiffness group than in the low arterial stiffness group among the hypertensive patients. The results of the Spearman's rank correlation coefficient test also indicated a strong positive correlation between the OPG and CAVI values (r=0.484, p < 0.001) in the hypertensive patients. In addition, a multivariate logistic regression analysis showed that age (odds ratio: 1.162, 95% confidence interval (CI): 1.070-1.263, p < 0.001), diastolic blood pressure (odds ratio: 1.109, 95% CI: 1.033-1.190, p=0.004), and serum OPG level (odds ratio: 1.275, 95% CI: 1.030-1.580, p=0.026) were independent predictors of arterial stiffness in hypertensive patients.

CONCLUSIONS

The serum OPG level is positively associated with arterial stiffness in hypertensive patients.

Evaluation of blood pressure control using a new arterial stiffness parameter, cardio-ankle vascular index (CAVI)

Arterial stiffness has been known to be a surrogate marker of arteriosclerosis, and also of vascular function. Pulse wave velocity (PWV) had been the most popular index and was known to be a predictor of cardiovascular events. But, it depends on blood pressure at measuring time. To overcome this problem, cardio-ankle vascular index (CAVI) is developed. CAVI is derived from stiffness parameter β by Hayashi, and the equation of Bramwell-Hill, and is independent from blood pressure at a measuring time. Then, CAVI might reflect the proper change of arterial wall by antihypertensive agents.

CAVI shows high value with aging and in many arteriosclerotic diseases and is also high in persons with main coronary risk factors. Furthermore, CAVI is decreased by an administration of α₁ blocker, doxazosin for 2-4 hours, Those results suggested that CAVI reflected the arterial stiffness composed of organic components and of smooth muscle cell contracture. Angiotensin II receptor blocker, olmesartan decreased CAVI much more than that of calcium channel antagonist, amlodipine, even though the rates of decreased blood pressure were almost same. CAVI might differentiate the blood pressure-lowering agents from the point of the effects on proper arterial stiffness.

This paper reviewed the principle and rationale of CAVI, and the possibilities of clinical applications, especially in the studies of hypertension.

Elevated arterial stiffness and diastolic dysfunction in subclinical hypothyroidism

BACKGROUND

Thyroid hormone is associated with arterial stiffness and left ventricular diastolic function in hypothyroid disease. The relationship of thyroid hormone level to cardio-ankle vascular index (CAVI) and left ventricular diastolic function, however, remains unclear in subjects with subclinical hypothyroidism.

METHODS AND RESULTS

We conducted a cross-sectional study of 83 patients with untreated subclinical hypothyroidism and compared them with 83 randomly selected controls from health check-ups. Log N-terminal prohormone of brain natriuretic peptide (NT-proBNP), C-reactive protein (CRP), and arterial stiffness were measured. In addition, we measured early diastolic mitral annular velocity (E') in 43 participants with subclinical hypothyroidism and in 40 controls. When compared with the control group, patients with subclinical hypothyroidism had higher logNT-proBNP (1.9±0.5 vs. 1.7±0.3pg/ml, P<0.05), CRP (0.22±0.04 vs. 0.09±0.06mg/dl, P<0.05), and CAVI (8.8±1.7 vs. 7.8±1.4, P<0.001) and lower E' (5.8±1.7 vs. 7.5±2.1cm/s, P<0.001). CAVI was significantly associated with logNT-proBNP, CRP and E' in the subclinical hypothyroidism group.

CONCLUSIONS

High logNT-proBNP was associated with a raised CAVI in patients with subclinical hypothyroidism. Subclinical hypothyroidism may be a risk factor for cardiovascular events related to arterial stiffening and left ventricular diastolic dysfunction.

Association between left ventricular hypertrophy and changes in arterial stiffness during hypertensive treatment

Cardio-ankle vascular index (CAVI) has been demonstrated as a parameter of arterial stiffness, which antihypertensive therapy may improve. However, little information is available about the factors affecting changes in arterial stiffness assessed by CAVI during antihypertensive therapy. We performed a study to examine the factors affecting changes in arterial stiffness assessed by CAVI during antihypertensive therapy. Eighty treated hypertensive patients (71 ± 10 years) were divided into two groups: 50 patients showing a decrease in CAVI (Group 1) and 30 patients showing an increase (Group 2) during observation (24 ± 11 months) of antihypertensive therapy. The groups did not differ in the rates of use of angiotensin II receptor blockers or calcium channel blockers. Age (Group 1: 67 ± 11 versus Group 2: 74 ± 8 years), left ventricular mass index (LVMI) (Group 1: 103 ± 19 versus Group 2: 120 ± 24 g/m(2)) and systolic blood pressure (Group 1: 133 ± 17 versus Group 2: 144 ± 23 mm Hg) at the start of observation were significantly higher in Group 2 than in Group 1 (p = 0.003, p = 0.001 and p = 0.027, respectively). The changes in CAVI during observation were correlated only with LVMI (r = 0.289, p = 0.009) at the start of observation for all 80 patients. It may be difficult to improve arterial stiffness assessed by CAVI during antihypertensive therapy in hypertensive patients with left ventricular hypertrophy.

Relationship between arterial stiffness and variability in systolic blood pressure during a single clinic visit in patients with hypertension

Objective

To examine factors affecting systolic blood pressure (SBP) variability during a single clinic visit, in treated hypertensive patients.

Methods

Hypertensive patients were recruited to this observational study. Blood pressure was measured using an automated blood pressure monitor when each patient arrived at the outpatient clinic and again when they saw the physician. Mean SBP and SBP variability during a single clinic visit were calculated. The cardio–ankle vascular index (CAVI), as a marker of arterial stiffness, was also measured.

Results

A total of 57 treated hypertensive patients (mean age 71 years) were included in the study. The mean SBP was positively correlated with age ( r = 0.457), while SBP variability was positively correlated with age ( r = 0.383), CAVI ( r = 0.330), and glycosylated haemoglobin ( r = 0.345) and triglyceride levels (r = 0.299).

Conclusion

Variability in SBP during a single clinic visit showed better correlations with arterial stiffness and risk factors for atherosclerosis than did mean SBP. Large SBP variability during a single clinic visit may reflect progression of atherosclerosis, in treated hypertensive patients.

Acute decrease of cardio-ankle vascular index with the administration of beraprost sodium

AIM

A novel arterial stiffness index, the cardio-ankle vascular index (CAVI), has been proposed. To clarify the properties of CAVI, the effects of beraprost sodium (BPS), a prostaglandin (PG) I2 analogue, which has a potent vasodilating effect, on CAVI were studied and comparing with brachialankle pulse wave velocity (baPWV) in healthy volunteers.

METHODS

Male volunteers (n=18, 46.3±4.2 yr) were enrolled in this study and administered BPS (40 µg). CAVI and baPWV were measured every hour for 4 hours.

RESULTS

When BPS was administered to 18 healthy volunteers, systolic blood pressure and diastolic blood pressure fluctuated slightly, but the means did not change. CAVI significantly decreased in the 1st hour from 8.3±0.34 (mean±SE) to 7.9±0.34 (p<0.05) and this decrease persisted for 3 hours, whereas baPWV did not significantly change. ΔbaPWV each time was significantly correlated with both Δsystolic blood pressure and Δdiastolic blood pressure, but ΔCAVI did not correlate with either Δsystolic blood pressure (r=-0.12, p=0.38) or Δdiastolc blood pressure (r=-0.22, p=0.10).

CONCLUSIONS

Beraprost sodium did not decrease blood pressure, but decreased CAVI, whereas baPWV did not change. These results indicate that CAVI partly reflected the contraction of arterial smooth muscle cells.

Association between arterial stiffness and pulmonary function in hypertensive patients

Arterial stiffness, assessed by cardio-ankle vascular index (CAVI), is clinically used to assess arteriosclerosis. Recently, pulmonary age, as determined by pulmonary function test, has been proposed by the Japanese Respiratory Society as a diagnostic measure for chronic obstructive pulmonary disease (COPD). This study aims to examine the association between CAVI and pulmonary function and to elucidate the correlation between vascular stiffness and pulmonary age in hypertensive patients. We enrolled a total of 45 hypertensive patients (70±9 years) who had been taking antihypertensive medications for at least 1 year. Pulmonary function was measured by the percentage of predicted forced vital capacity (FVC) and the ratio of forced expiratory volume in 1 s (FEV(1)) to FVC (FEV(1)/FVC ratio). Pulmonary age was determined by the equation proposed by the Japanese Respiratory Society. CAVI was measured at the same clinic visit. In the simple correlation analysis CAVI correlated with the FEV(1)/FVC ratio (r=-0.399, P=0.007) and pulmonary age (r=0.559, P<0.001). Multiple linear regression analysis revealed that CAVI was independently associated with FEV(1)/FVC ratio (β=-0.418, P=0.014) and pulmonary age (β=0.514, P=0.002). In addition, CAVI was significantly higher in patients with increased pulmonary age (9.4±1.4) than in those with normal pulmonary age (8.4±0.9) (P=0.011). The present study indicates that an increased CAVI is independently associated with reduced pulmonary function and increased pulmonary age. Hypertensive patients with high CAVI may need to be monitored for the progression of COPD.

Association of cardio-ankle vascular index with brain natriuretic peptide levels in hypertension

AIMS

Plasma brain natriuteric peptide (BNP) is an established marker of cardiovascular events in individuals without heart failure. Although the cardio-ankle vascular index (CAVI) is clinically used as a parameter of arterial stiffness, its usefulness for predicting cardiovascular events has not been fully examined. This study aimed to evaluate the association among CAVIs, plasma BNP levels and left ventricular (LV) hypertrophy and dysfunction in hypertensive patients.

METHODS

We enrolled 136 hypertensive patients (69±10 years) who had been taking antihypertensive medications for at least one year. Echocardiography was performed to evaluate LV hypertrophy and function. Plasma BNP levels and CAVIs were also measured simultaneously.

RESULTS

CAVI was correlated with plasma BNP (r =0.245, p =0.004). Multiple linear regression analysis revealed three independent determinants of CAVI: age (β =0.568, p <0.001), diameter of ascending aorta (β =0.289, p <0.001), and diabetes (β =0.207, p =0.003). In addition, multiple linear regression analysis revealed two independent determinants of the plasma BNP level: left atrial diameter (β =0.334, p <0.001) and CAVI (β =0.256, p =0.002).

CONCLUSION

The present study indicates that increased CAVI is independently associated with elevated plasma BNP produced by increased LV afterload, that is, arterial stiffness, in hypertensive patients. Moreover, the present study raises the possibility that CAVI may be as useful as the plasma BNP level for predicting the risk of cardiovascular events in hypertensive patients.

Associations between cardio-ankle vascular index and microvascular complications in type 2 diabetes mellitus patients

AIM

Type 2 diabetes mellitus (T2DM) is a risk factor for increased arterial stiffness. We evaluated associations between the cardio-ankle vascular index (CAVI) and carotid plaque, intima media thickness (IMT), and diabetic microvascular complications in Korean T2DM patients.

METHODS

We conducted a retrospective, cross-sectional study of 320 Korean T2DM patients without a history of macrovascular disease or macroalbuminuria. We measured 24-hour urinary albumin excretion (UAE) levels and performed funduscopic and neuropathy examinations to assess the extent of diabetic microvascular complications. Arterial stiffness was assessed using CAVI. We also measured the ankle-brachial index (ABI), common carotid artery IMT, and carotid beta stiffness index.

RESULTS

Among the 320 patients enrolled in this study, 64 (20%) had increased CAVI (≥ 9). We found that CAVI was correlated with systolic blood pressure, pulse pressure, IMT, carotid beta stiffness index, log-transformed UAE, and total cholesterol. In multiple logistic regression analysis, mean IMT and the presence of carotid plaque were independently associated with increased CAVI (≥ 9) (OR=5.77, P < 0.01; OR=5.36, P < 0.001, respectively). Furthermore, an increased CAVI was associated with peripheral neuropathy (OR=2.03, P = 0.03) and microalbuminuria (OR=2.47, P < 0.01) after adjusting for possible confounding variables.

CONCLUSIONS

The results of this study suggest that increased CAVI is associated with the presence of arterial plaque, increased IMT, and microvascular complications, such as nephropathy and neuropathy, in T2DM patients.

Contradictory effects of β1- and α1- aderenergic receptor blockers on cardio-ankle vascular stiffness index (CAVI)--CAVI independent of blood pressure

AIM

The cardio-ankle vascular stiffness index (CAVI) is a new parameter that reflects the stiffness of the aorta, femoral artery and tibial artery as a whole. One of its conspicuous features is that CAVI is independent of blood pressure at measuring time, theoretically. But, it has not been experimentally proved yet. For confirmation, pharmacological studies were performed comparing with brachial-ankle pulse wave velocity (baPWV).

METHODS

Used drugs were a β1-adrenoceptor blocker, metoprorol and an α1- adrenoceptor blocker doxazosin. Both were administered to 12 healthy volunteer men. CAVI and baPWV were measured every one hour for 6 hours using VaSera.

RESULTS

When metoprolol (80 mg) was administered to 12 healthy volunteer men, systolic blood pressure decreased from 131.4 ± 4.5 to 118.3 ± 4.1 mmHg (mean ± SE) (p < 0.05) at the 3rd hour, and diastolic blood pressure decreased from 85.3 ± 4.0 to 75.3 ± 3.0 mm Hg (p < 0.05). baP-WV decreased from 13.93 ± 0.46 to 12.46 ± 0.49 m/sec (p < 0.05), significantly, but CAVI did not change (8.16 ± 0.29 to 8.24 ± 0.27) (p = 0.449). ΔbaPWV at each time was significantly correlated with both Δsystolic and Δdiastolic blood pressures, but ΔCAVI was not correlated with either Δblood pressure. When doxazosin (4 mg) was administered to the same men, systolic blood pressure decreased from 130.2 ± 4.6 to 117.2 ± 4.8 mmHg (p < 0.05) at the 3rd hour. Diastolic blood pressure also decreased from 85.1 ± 4.1 to 74.2 ± 3.9 mmHg (p < 0.05). baPWV decreased from 13.98 ± 0.68 to 12.25 ± 0.53 m/sec (p < 0.05), significantly. CAVI also decreased from 8.15 ± 0.28 to 7.18 ± 0.37 (p < 0.05), significantly.

CONCLUSION

These results suggested that CAVI was not affected by blood pressure at the measuring time directly, but affected by the changes of contractility of smooth muscle cells.

Urinary cystatin C as a potential risk marker for cardiovascular disease and chronic kidney disease in patients with obesity and metabolic syndrome

BACKGROUND AND OBJECTIVES

Obesity and metabolic syndrome (MS) increase the risk of cardiovascular disease (CVD), chronic kidney disease (CKD), and all-cause mortality. Serum cystatin C (S-CysC), a marker of GFR, has been shown to be associated with CVD and CKD. This study was designed to elucidate the association of urinary CysC (U-CysC), a marker of renal tubular dysfunction, with CVD and CKD risk factors in patients with obesity and MS.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The U-CysC-creatinine ratio (UCCR) was examined in 343 Japanese obese outpatients enrolled in the multi-centered Japan Obesity and Metabolic Syndrome Study.

RESULTS

UCCR was positively correlated with urine albumin-creatinine ratio (UACR) and S-CysC and negatively correlated with estimated GFR (eGFR). Among obese patients, UCCR was significantly higher in MS patients than in non-MS patients. UCCR had significant correlations with the number of components of MS and arterial stiffness, all of which are CVD predictors, similarly to UACR (P<0.05). Interestingly, diet- and exercise-induced weight reduction for 3 months significantly decreased only UCCR among all of the renal markers examined (P<0.01), in parallel with the decrease in BMI, HbA1c, and arterial stiffness, suggesting the beneficial effect of weight reduction on renal tubular dysfunction.

CONCLUSIONS

This study demonstrates that UCCR is significantly associated with renal dysfunction, the severity of MS, arterial stiffness, and weight change in obese patients. The data of this study suggest that U-CysC could serve as a CVD and CKD risk factor in patients with obesity and MS.

Cystatin C and blood pressure: results of 24 h ambulatory blood pressure monitoring

BACKGROUND

The relationship between kidney function and blood pressure (BP) components has been studied in chronic kidney disease patients. Whether cystatin C, a marker of kidney function, is associated in the normal range with systolic BP (SBP), diastolic BP (DBP), and pulse pressure (PP) obtained using ambulatory blood pressure monitoring has not been previously studied.

METHODS

The sample subjects were 53 males and 34 females, mean age was 59.3+/-13.5 years. 76% were receiving antihypertensive drug treatment. Kidney function was evaluated by measuring serum cystatin C. Microalbuminuria was measured in a 24h urine collection. Glomerular filtration rate (GFR) was estimated using the abbreviated Modification of Diet in Renal Disease equations. The ambulatory BP was measured non-invasively for 24h by the Spacelab devices programmed to measure BP every 15 min during daytime and every 20 min during nighttime.

RESULTS

The highest quartile of cystatin C distribution showed an older age and worsel parameters of renal function (cystatin C, serum creatinine and GFR) than the other groups. No differences for gender or diabetes were found. 24h SBP and PP were higher in the fourth quartile compared to the fist one (p<0.01). 24h DBP was lower for the patients in the fourth quartile of cystatin C compared which any one of the other groups (p<0.001). The relationship between cystatin C, as well as GFR, with SBP and PP was statistically significant as renal function comes down. Contrariwise, as cystatin C increases DBP declines; but the correlation with GFR measured through MDRD 4 is not significant. In the same way, no correlation was found for GFR and microalbuminuria, but there was a statistically significant positive relationship between cystatin C and microalbuminuria severity (p<0.01). Multivariate regression analysis confirms these findings.

CONCLUSIONS

Both SBP and pulse pressure were significantly associated with kidney function. DBP was negatively correlated with cystatin C concentrations but not with GFR. Cystatin C shows a positive relationship with microalbuminura severity. Cystatin C might have cardiovascular effects beyond its use as a marker of the renal function.