Cardio-ankle vascular index and cardiovascular disease: Systematic review and meta-analysis of prospective and cross-sectional studies

Contribution of cardio-ankle vascular index to prediction of cardiovascular events in the adult urban population: data from the ESSE-RF study (Tomsk)

Aim. To determine the role of cardio-ankle vascular index (CAVI) in predicting cardiovascular events (CVEs) in adult Russian population using model of the Epidemiology of Cardiovascular Diseases and their Risk Factors in Regions of Russian Federation (ESSE-RF) study (Tomsk).

Material and methods. We analyzed the data of 1342 people aged 25-64 (4,3±11,6) years, in whom arterial stiffness was assessed as part of the ESSE-RF study using the vascular screening system VaSeraVS-1500, followed by phone contacts, on average, 4,7 years later. We studied the prognostic role of CAVI in relation to primary composite (cardiovascular death, nonfatal myocardial infarction (MI) or stroke) and secondary composite (all CVEs) endpoints.

Results. We revealed that prior myocardial infarction or stroke (n=52) is associated with an increase in CVE incidence from 2,3 to 11,5% (p=0,0003) and from 5% to 23% (p<0,001) for primary and secondary composite endpoints, respectively. In a group of 1290 people (without prior MI or stroke), CAVI was significantly higher in men than in women: 7,4±1,4 vs 7,1±1,3 (p=0,002), despite more young age: 45,4±11,8 vs 48,0±11,3 years (p<0,001). The risk criterion for CVE was CAVI >7,8 (relative risk (RR): 5,06; 95% confidence interval (CI): 2,32-11,06) (p<0,001) and (RR: 3,95; 95% CI: 2,37-6,58) (p<0,001), which retains its predictive value when adjusted for conventional risk factors (RR: 3,13; 95% CI: 1,26-7,75) (p=0,014) and (RR: 2,16; 95% CI: 1,18-3,98) (p=0,013) — primary and secondary composite endpoints, respectively.

Conclusion. CAVI has a significant independent value in predicting CVEs in Tomsk adult urban population aged 25-64 years. To clarify the cardiovascular risk, vascular screening with identifying CAVI should be carried out during preventive and screening examinations for men over 35 and women over 45.

Green coffee: economic relevance and a systematic review of the effects on human health

Coffee is probably the most popular beverage after water and is an important component in diet and health since its consumption is high worldwide. Globally, it is the most relevant food commodity being just behind crude oil. Besides its pleasant flavor, it is an antioxidant source due to polyphenols, which are protective compounds against several diseases. This study aimed to evaluate the economic relevance and perform a systematic review of green coffee's effects on human health. Databases such as MEDLINE-PubMed, EMBASE, COCHRANE, and GOOGLE SCHOLAR were searched, and PRISMA guidelines were followed. Green coffee is considered a novel food product because consumers usually consume only roasted coffee. It can be marketed as such or as an extract. Due to the content of bioactive compounds, which are partially lost during the roasting process, the extracts are usually marketed concerning the potential regarding health effects. Green coffee can be used as dietary supplements, cosmetics, and pharmaceuticals, as a source of antioxidants. It can benefit human health, such as improvement in blood pressure, plasma lipids, and body weight (thus contributing to the improvement of risk components of Metabolic Syndrome). Moreover, benefits for cognitive functions may also be included.

Cardio-Ankle Vascular Index Predicts Post-Discharge Stroke in Patients with Heart Failure

AIM

We aimed to evaluate the significance of the cardio-ankle vascular index (CAVI) to predict stroke in patients with heart failure (HF).

METHODS

This was a prospective observational study, which recruited clinical data from a total of 557 patients who had been hospitalized for HF and undergone CAVI. According to the receiver operating characteristic curve analysis, the accurate cut-off value of CAVI in predicting post-discharge stroke was 9.64. We divided the patients into two groups: the high-CAVI group (HF patients with CAVI ≥ 9.64, n=111, 19.9%) and the low-CAVI group (HF patients with CAVI ＜9.64, n=446, 80.1%). We compared the patients' characteristics and post-discharge prognosis. The primary endpoint was stroke.

RESULTS

The high-CAVI group was older (73.0 vs. 65.5 years old, P＜0.001). Male sex (73.9% vs. 61.4%, P=0.015), coronary artery disease (47.7% vs. 36.1%, P=0.024), and diabetes mellitus (54.1% vs. 37.4%, P=0.001) were more prevalent in the high-CAVI group. In contrast, there was no difference in left ventricular ejection fraction, and prevalence of hypertension and dyslipidemia. The Kaplan-Meier analysis demonstrated that post-discharge stroke rate was higher in the high-CAVI group than in the low-CAVI group (log-rank P=0.005). In multivariate Cox proportional hazard analysis, high CAVI was found to be an independent predictor of stroke, with an adjusted hazard ratio of 3.599, compared to low CAVI.

CONCLUSION

CAVI independently predicts stroke in patients with HF.

Arterial Stiffness Assessed by Cardio-Ankle Vascular Index in Patients With Abdominal Aortic Aneurysm and Its Alterations After Treatment

PURPOSE

The aim of the present study was to investigate a potential difference on the arterial stiffness among aneurysm patients and non-aneurysm controls, as well as to explore potential changes between patients treated either with endovascular or open repair.

MATERIALS AND METHODS

A 110 patients with an infrarenal AAA were prospectively enrolled in this study. Fifty-six patients received an EVAR, whereas 54 patients received an open surgical repair. Moreover, 103 gender and age-matched subjects without AAA served as controls. The cardio-ankle vascular index (CAVI) was applied for measurement of the arterial stiffness.

RESULTS

CAVI values were statistically higher in the AAA patients when compared with control subjects. Although at 48 hours postoperatively the CAVI values were increased in both groups when compared to baseline values, the difference in CAVI had a tendency to be higher in the open group compared to the endovascular group. At 6 months of follow up the CAVI values returned to the baseline for the patients of the open repair group. However, in the endovascular group CAVI values remained higher when compared with the baseline values.

CONCLUSION

Patients with AAAs demonstrated a higher value of CAVI compared to healthy controls. A significant increase of arterial stiffness in both groups during the immediate postoperative period was documented. The increase in arterial stiffness remained significant at 6 months in EVAR patients. Further studies are needed to elucidate the impact of a decreased aortic compliance after stentgraft implantation on the cardiac function of patients with AAA.

Cardio-ankle vascular index represents the best surrogate for 10-year ASCVD risk estimation in patients with primary hypertension

Background: Identification of target organ damage and/or risk-enhancing factors help treatment decisions in hypertensive and hyperlipidaemic patients who reside in borderline to an intermediate risk category based on 10-year atherosclerotic cardiovascular disease (ASCVD) risk estimates.Aim: In the present study, we aimed to investigate the comparative efficacy of certain hypertension-mediated organ damage markers (HMOD) for the prediction of 10-year ASCVD risk ≥10%, in patients with primary hypertension without established CVD.Methods: One-hundred thirty-seven asymptomatic hypertensive patients ≥40 years of age were enrolled in the present study. Ten-year ASCVD risks were estimated by Pooled Cohort Equations. The following HMOD markers; pulse pressure (PP), left ventricular mass index (LVMI), carotid intima-media thickness (CIMT), ankle-brachial index (ABI), cardio-ankle vascular index (CAVI) and estimated glomerular filtration rate (eGFR) were evaluated with respect to efficacy for predicting ≥10% ASCVD risk with ROC analysis.Results: CAVI gave the greatest Area Under Curve (AUC = 0.736, p < .000), and followed by CIMT (AUC = 0.727, p < .000), LVMI (AUC = O.630, p = .01), and PP (AUC = 0.623, p = .02). ABI and eGFR were not found to be predictive. CAVI correlated best with estimated 10-year ASCVD risk (r = 0.460, p < .000). A CAVI value ≥8 was found 71% sensitive and 72% specific for predicting ≥10% risk in 10-year ASCVD risk scale. CAVI gave the best graded response to increments in 10-year ASCVD risk categories.Conclusion: We suggest that CAVI is the best surrogate for 10-year ASCVD risk, among several HMOD markers.

Beneficial Effect of Statin Therapy on Arterial Stiffness

Arterial stiffness describes the increased rigidity of the arterial wall that occurs as a consequence of biological aging and several diseases. Numerous studies have demonstrated that parameters to assess arterial stiffness, especially pulse-wave velocity, are predictive of those individuals that will suffer cardiovascular morbidity and mortality. Statin therapy may be a pharmacological strategy to improve arterial elasticity. It has been shown that the positive benefits of statin therapy on cardiovascular disease is attributable not only to their lipid-lowering capacity but also to various pleiotropic effects, such as their anti-inflammatory, antiproliferative, antioxidant, and antithrombotic properties. Additionally, statins reduce endothelial dysfunction, improve vascular and myocardial remodeling, and stabilize atherosclerotic plaque. The aim of the present review was to summarize the evidence from human studies showing the effects of statins on arterial stiffness.

Arterial Stiffness Index and Exercise Tolerance in Patients Undergoing Cardiac Rehabilitation

Arterial stiffness contributes to the development of cardiovascular disease (CVD). However, the relationship between the arterial stiffness and exercise tolerance in CVD patients with preserved ejection fraction (pEF) and those with reduced EF (rEF) is unclear. We enrolled 358 patients who participated in cardiac rehabilitation and underwent cardiopulmonary exercise testing at Juntendo University Hospital. After excluding 195 patients who had undergone open heart surgery and 20 patients with mid-range EF, the patients were divided into pEF (n = 99) and rEF (n = 44) groups. Arterial stiffness was assessed using arterial velocity pulse index (AVI) and arterial pressure volume index (API) at rest. The patients in the pEF group were significantly older and had a higher prevalence of coronary artery disease than the rEF group. The pEF group had significantly lower AVI levels and higher API levels than the rEF group. In the pEF group, the peak oxygen uptake (peak VO₂) and the anaerobic threshold was significantly higher than those in the rEF group. The peak VO₂ was significantly and negatively correlated with AVI and API in the pEF group (All, P < 0.05), but not in the rEF group. Multivariate linear regression analyses demonstrated that AVI was independently associated with peak VO₂ (β = -0.34, P < 0.05) in the pEF group. In conclusion, AVI may be a useful factor for assessing exercise tolerance, particularly in CVD patients with pEF.

Cardio-Ankle Vascular Index in the Persons with Pre-Diabetes and Diabetes Mellitus in the Population Sample of the Russian Federation

The aim of this study was to evaluate Cardio-Ankle Vascular Index (CAVI) and increased arterial stiffness predictors in patients with carbohydrate metabolism disorders (CMD) in the population sample of Russian Federation. Methods: 1617 patients (age 25–64 years) were enrolled in an observational cross-sectional study Epidemiology of Cardiovascular Diseases and Their Risk Factors in the Regions of the Russian Federation (ESSE-RF). The standard ESSE-RF protocol has been extended to measure the cardio-ankle vascular index (CAVI), a marker of arterial stiffness. Patients were divided into three groups: patients with type 2 diabetes mellitus (n = 272), patients with prediabetes (n = 44), and persons without CMD (n = 1301). Results: Median CAVI was higher in diabetes and prediabetes groups compared with group without CMD (p = 0.009 and p < 0.001, respectively). Elevated CAVI (≥9.0) was detected in 16.8% of diabetes patients, in 15.9% of those with prediabetes, and in 9.0% of those without CMD (p < 0.001). The factors affecting on CAVI did not differ in CVD groups. In logistic regression the visceral obesity, increasing systolic blood pressure (SBP) and decreasing glomerular filtration rate (GFR) were associated with a pathological CAVI in CMD patients, and age, diastolic blood pressure (DBP), and cholesterol in persons without CMD. Conclusions: the CAVI index values in the prediabetes and diabetes patients were higher than in normoglycemic persons in a population sample of the Russian Federation. Since the identified disorders of arterial stiffness in prediabetes are similar to those in diabetes, their identification is important to prevent further cardiovascular complications.

Association of the Estimated Coronary Artery Incidence Risk According to the Japan Atherosclerosis Society Guidelines 2017 with Cardio-Ankle Vascular Index

Aims: The categories in the comprehensive lipid and risk management guidelines were proposed by the Japan Atherosclerosis Society (JAS Guidelines 2017), which adopted the estimated 10 year absolute risk of coronary artery disease (CAD) incidence in the Suita score. We examined whether those categories were concordant with the degree of arterial stiffness.

Methods: In 2014, the cardio-ankle vascular index (CAVI), an arterial stiffness parameter, was measured in 1,972 Japanese participants aged 35–74 years in Tsuruoka City, Yamagata Prefecture, Japan. We examined the mean CAVI and the proportion and odds ratios (ORs) of CAVI ≥ 9.0 on the basis of the following three management classifications using the analysis of variance and logistic regression: “Category I (Low risk),” “Category II (Middle risk),” and “Category III (High risk).”

Results: The mean CAVI and proportion of CAVI ≥ 9.0 were 8.6 and 34.8% among males and 8.1 and 18.3% among females, respectively. The mean CAVI and proportion of CAVI ≥ 9.0 were associated with an estimated 10 year absolute risk for CAD among males and females, excluding High risk for females. These results were similar to the management classification by the guideline: the multivariable-adjusted ORs (95% confidence intervals) of CAVI ≥ 9.0 among Category II and Category III compared with those among Category I were 2.96 (1.61–5.43) and 7.33 (4.03–13.3) for males and 3.99 (2.55–6.24) and 3.34 (2.16–5.16) for females, respectively.

Conclusions: The risk stratification, which was proposed in the JAS Guidelines 2017, is concordant with the arterial stiffness parameter.

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.

Prevalence of obesity in women of different ages and its relationship with arterial stiffness

Background. General and abdominal obesity is widespread among women in the Russian population. The relationship between obesity and arterial stiffness, as a predictor of the development of cardiovascular diseases, in women of different ages remains unclear. Aims: to study the relationship between obesity and arterial stiffness and dynamics of central aortic pressure in women of different ages with preserved and lost reproductive function. Methods. 161 women were examined and divided into 3 groups. Two groups included women with preserved reproductive function: group 1 consisted of 52 young women aged from 18 to 30 years (23.8 5.3 years); group 2 included 54 women aged from 31 years to the menopause (41 5.9 years). Group 3 included 55 postmenopausal women (55.4 5.8 years). All the women underwent a clinical examination with anthropometry; questioning; 24-hour monitoring of the dynamics of blood pressure with measuring the indicators of arterial stiffness and daily aortic central pressure; determination of the carotid-femoral pulse wave velocity (cfPWV); study of vascular stiffness by volume sphygmography. Results. The anthropometric data in groups 2 and 3 were comparable in terms of the prevalence of general obesity (GO). Abdominal obesity (AO) was detected in 19.2% of the 1st group; 51.9% of the 2nd and 76.4% of the 3rd group. In the 1st group AO had the strongest correlation with the aortic pulse wave velocity PWVao (R = 0.41, p = 0.002) and the corrected to HR75 augmentation index Aixao (R = 0.38, p = 0.005). In the 2nd group AO correlates with cfPWV (R = 0.4, p = 0.003); GO with PWVao (R = 0.38, p = 0.005) and aortic cardio-ankle vascular index CAVIao (R = 0.48, p = 0.001). In the 2nd group AO and GO are also interconnected with the central and peripheral pressure. In the 3rd group AO correlates with PWVao (R = 0.33, p = 0.01), cfPWV (R = 0.32, p = 0.02); GO with the index of the double product IDP (R = 0.36, p = 0.01). Conclusions. Obesity, especially its abdominal type, is an important factor determining the development of vascular wall stiffness in women of the reproductive age. It is necessary to conduct a comprehensive assessment of arterial stiffness and daily dynamics of central aortic pressure in women of all ages, suffering from obesity and, first of all, its abdominal type, in order to early diagnose subclinical changes in the vascular wall and central hemodynamic disorders.

Arterial stiffness measured by cardio-ankle vascular index is greater in non-obese young women with polycystic ovarian syndrome

AIM

The association of metabolic abnormalities and polycystic ovarian syndrome (PCOS) has been documented, but few studies have focused on cardiovascular risk in these women. The aim of this study was to compare arterial stiffness by using the cardio-ankle vascular index (CAVI) in PCOS women with controls, and to evaluate whether any clinical or laboratory variables had independent associations with it.

METHODS

A group of 160 women, matched for age and body mass index were recruited. Diagnosis of PCOS was made according to the Rotterdam criteria. Arterial stiffness using CAVI was evaluated in non-obese young woman, with and without PCOS.

RESULTS

In the PCOS group (n = 80), 60 cases (75%) had findings of hyperandrogenism, 59 (73.8%) had ovulatory dysfunction, and 70 (87.5%) had an ultrasonographic appearance of polycystic ovaries. Women with PCOS had significantly higher mean CAVI values when compared to subjects without PCOS (5.78 ± 0.64 vs 5.28 ± 0.77, P < 0.001). Multiple regression analysis revealed that androgen excess was associated with increased arterial stiffness, independent of ovulatory dysfunction, polycystic ovaries, body mass index and age.

CONCLUSION

This data suggests that vascular compliance is decreased in young women with PCOS. Androgen excess is independently associated with increased arterial stiffness.

Association of Arterial Stiffness With Kidney Function Among Adults Without Chronic Kidney Disease

BACKGROUND

Our aims were to assess whether arterial stiffness is associated with a higher risk for kidney dysfunction among persons without chronic kidney disease (CKD).

METHODS

We analyzed data from the national health checkup system in Japan; for our analyses, we selected records of individuals who completed assessments of cardio-ankle vascular index (CAVI) and kidney function from 2005 to 2016. We excluded participants who had CKD at baseline, defined as the presence of proteinuria or estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2. We compared 2 groups of CAVI measurements-the highest quartile (≧8.1) and the combined lower 3 quartiles (<8.1). We used Cox proportional hazards models to assess associations between these 2 groups and subsequent CKD events, proteinuria, eGFR <60 ml/min/1.73 m2, and rapid eGFR decline (greater than or equal to -3 ml/min/1.73 m2 per year).

RESULTS

The mean age of the 24,297 included participants was 46.2 years, and 60% were female. Over a mean follow-up of 3.1 years, 1,435 CKD events occurred. In a multivariable analysis, the hazard ratios with 95% confidence intervals (CIs) for the highest vs. combined lower quartiles of CAVI measurements were 1.3 (1.1, 1.5) for CKD events, 1.3 (0.96, 1.62) for proteinuria, 1.4 (1.1, 1.7) for eGFR <60 ml/min/1.73 m2, and the odds ratio with 95% CI was 1.3 (1.1, 1.4) for rapid eGFR decline.

CONCLUSIONS

Persons with CAVI measurements ≧8.1 had a higher risk for CKD events compared with their counterparts with CAVI measurements <8.1. Greater arterial stiffness among adults without CKD may be associated with kidney dysfunction.

Cardio-ankle vascular index (CAVI) measured by a new device: protocol for a validation study

INTRODUCTION

Cardio-ankle vascular index (CAVI) is a new marker of arterial stiffness (AS) that can assess vascular wall stiffness in the aorta, femoral artery and tibial artery. CAVI is less affected by blood pressure at the time of measurement than the gold standard method (carotid-femoral pulse wave velocity (PWV)). Our group has developed a device called VOPITB (Velocidad Onda de Pulso Índice Tobillo Brazo) that uses the oscillometric method and easily and accurately measures the PWV in the arms and legs separately, allowing new AS indices to be studied. This article describes the research protocol to determine CAVI using VOPITB and to validate the device against a reference device (VaSera VS-1500) and assess its clinical utility.

METHODS AND ANALYSES

A cross-sectional, descriptive and observational study will be conducted. In all, 120 subjects (a minimum of 40% of subjects from any one gender) will be evaluated. CAVI will be determined from the measurement by VOPITB and VaSera VS-1500. For each subject, the average of the three readings taken with each device will be calculated. The Bland-Altman plot will be used to determine whether any bias exists in the data-that is, a tendency of the size of the difference to vary with the mean. The participants will be divided roughly equally between the following age bands: <30, 30-60 and >60 years.

ETHICS AND DISSEMINATION

The study has been approved by the ethics committee of the Hospital San Pedro de Alcántara, Cáceres, Spain. The participants will be required to sign an informed consent form before inclusion in the study, in accordance with the Declaration of Helsinki and WHO standards for observational studies. The dissemination plan of the research study results will be through presentations in relevant national and international conferences and scientific publications in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04303546.

Relationship between cardio-ankle vascular index and obstructive sleep apnea

Patients with obstructive sleep apnea (OSA) are susceptible to developing atherosclerosis. Consequently, such patients are at a high risk of developing cardiovascular diseases, leading to poor prognosis. Many physiological parameters have been previously used to predict the development of atherosclerosis. One such parameter, the cardio-ankle vascular index (CAVI), a measure of arterial stiffness, has garnered much attention as it can also predict the degree of atherosclerosis. The CAVI can be calculated based on noninvasive measurements, and is less susceptible to blood pressure variations at the time of measurement. Therefore, the CAVI can assess changes in arterial stiffness and the risk of developing atherosclerosis independent of blood pressure changes. Continuous positive airway pressure (CPAP) is a standard therapy for OSA and can suppress the issue significantly. Several studies have shown that CPAP treatment for OSA could also reduce the CAVI. In this review, we discuss the relationship between OSA and arterial stiffness, primarily focusing on the CAVI. Furthermore, we propose future perspectives for the CAVI and OSA.

Dose of Alcohol From Beer Required for Acute Reduction in Arterial Stiffness

Acute beer or alcohol ingestion reduces arterial stiffness, but the dose required to reduce arterial stiffness is unclear. Therefore, this study aimed to determine the acute effects of ingesting various amounts of beer on arterial stiffness in healthy men. Nine men (20–22 years) participated, in eight trials in random order on different days. The participants each consumed 25, 50, 100, or 200 mL of alcohol-free beer (AFB25, AFB50, AFB100, and AFB200) or regular beer (B25, B50, B100, and B200), and were monitored for 60 min thereafter. Arterial stiffness did not significantly change among all AFB and B25. However, B50, B100, and B200 caused a significant decrease in arterial stiffness for approximately 30–60 min: heart-brachial pulse wave velocity (B50: −4.5 ± 2.4%; B100: −3.4 ± 1.3%; B200: −8.1 ± 2.6%); brachial-ankle pulse wave velocity (B50: −0.6 ± 2.0%; B100: −3.3 ± 1.1%; B200: −9.3 ± 3.0%); heart-ankle pulse wave velocity (B50: −3.7 ± 0.3%; B100: −3.3 ± 0.9%; B200: −8.1 ± 2.7%); and cardio-ankle vascular index (B50: −4.6 ± 1.3%; B100: −5.6 ± 0.8%; B200: −10.3 ± 3.1%). Positive control alcoholic beverages reduced arterial stiffness, and these reductions did not significantly differ regardless of the type of beverage. Our data show that consuming about 50 mL of beer can start to reduce arterial stiffness, and that the reduced arterial stiffness is mainly attributable to the alcohol in beer.

The Relationship Between Alcohol Consumption With Vascular Structure and Arterial Stiffness in the Spanish Population: EVA Study

BACKGROUND

Controversy exists regarding the way alcohol use is associated with vascular structure and arterial stiffness parameters. The purpose of this study is to evaluate the association between alcohol consumption with vascular structure and arterial stiffness in an adult population.

METHODS

We conducted a cross-sectional study. Five hundred and one participants were recruited by random sampling from an urban population of 43,946 individuals aged 35 to 75 years, assigned from 5 healthcare centers located in Salamanca, Spain. This was a subanalysis of the EVA study. Arterial stiffness was assessed by measuring cardio-ankle vascular index (CAVI) and brachial-ankle pulse wave velocity (ba-PWV) with the VaSera VS-1500^® device, and carotid-femoral pulse wave velocity (cf-PWV) with the Sphygmocor^® . Vascular structure was evaluated by measuring the carotid intima-media thickness (c-IMT) with a Sonosite Micromax^® ultrasound. Alcohol consumption was calculated using a standardized questionnaire and quantified in g/wk.

RESULTS

In the multiple regression analysis adjusted for sex, age, smoking status, and systolic blood pressure, the c-IMT and cf-PWV values of individuals drinking > 70 g/wk were higher than those of the reference group (nondrinkers) by 0.02 mm (p = 0.030) and 0.42 m/s (p = 0.021), respectively. The association between alcohol consumption with vascular structure and arterial stiffness only attains statistical significance for cf-PWV (p = 0.039) and c-IMT (p = 0.019), showing an association which suggests a J-shaped association. This association was not statistically significant for ba-PWV and CAVI (p = 0.446 and p = 0.141, respectively), although a similar trend was observed with ba-PWV.

CONCLUSIONS

The results of this study suggest that heavy alcohol consumption (>70 g/wk) is associated with increased c-IMT and cf-PWV. Moreover, we found a J-shaped association between alcohol consumption and c-IMT and cf-PWV values as markers of vascular structure and arterial stiffness, with no association with ba-PWV and CAVI being observed.

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.

[Predictive value of vascular health indicators on newly cardiovascular events: Preliminary validation of Beijing vascular health stratification system]

OBJECTIVE

To explore the predictive value of carotid femoral artery pulse wave velocity (CF-PWV), carotid radial artery pulse wave velocity (CR-PWV), cardio-ankle vascular index (CAVI), and ankle brachial index (ABI) on coronary heart disease (CHD) and cerebral infarction (CI), and the preliminary validation of Beijing vascular health stratification (BVHS).

METHODS

Subjects with at least 2 in-patient records were included into the study between 2010 and 2017 from Vascular Medicine Center of Peking University Shougang Hospital. Subjects with CHD or CI, and without data of vascular function at baseline were excluded. Eventually, 467 subjects free of CHD [cohort 1, mean age: (63.4±12.3) years, female 42.2%] and 658 subjects free of CI [cohort 2, mean age: (64.3±12.2) years, female 48.7%] at baseline were included. The first in-patient records were as the baseline data, the second in-patient records were as a following-up data. Cox proportional hazard regression was used to establish the predictive models of CHD or CI derived from BVHS by multivariable-adjusted analysis.

RESULTS

The median follow-up time of cohort 1 and cohort 2 was 1.9 years and 2.1 years, respectively. During the follow-up, 164 first CHD events occurred in cohort 1 and 117 first CI events occurred in cohort 2. Four indicators were assessed as continuous variables simultaneously by multivariable-adjusted analysis. In cohort 1, CF-PWV, CR-PWV, ABI, and CAVI reached statistical significance in the multivariable-adjusted models (P<0.05). In cohort 2, only CAVI (P<0.05) was of statistical significance. In addition, the higher CF-PWV became a protector of CHD or CI (P<0.05). The prediction value of BVHS reached the statistical significance for CHD and CI in the unadjusted models (all P<0.05), however, BVHS could only predict the incidence of CHD (P<0.05), but not the incidence of CI (P>0.05) in the multivariable-adjusted models. CF-PWV, CR-PWV, ABI, and CAVI were associated factors of CHD independent of each other (P<0.05), only CAVI (P<0.05) was the risk factor of CI independent of the other three.

CONCLUSION

The different vascular indicators might have different effect on CHD or CI. CAVI might be a stable predictor of both CHD and CI. Higher baseline CF-PWV was not necessarily a risk factor of CHD or CI because of proper vascular health management. BVHS was a potential factor for the prediction of CHD, and further research is needed to explore the prediction value for CI.

The effect of soy isoflavones on arterial stiffness: a systematic review and meta-analysis of randomized controlled trials

PURPOSE

Some but not all randomized controlled trials (RCTs) of soy isoflavones showed their beneficial effect on arterial stiffness, a predictor of cardiovascular events, dementia, and all-cause mortality, independent of traditional risk factors. To test the hypothesis that supplementation of soy isoflavones reduces arterial stiffness, we performed a systematic review and meta-analysis of RCTs of soy isoflavones on arterial stiffness.

METHODS

The protocol of this systematic review was registered with PROSPERO (CRD42019126128) and written in accordance with PRISMA. The PubMed, Embase, and clinicaltrials.gov databases were searched using the following criteria: human subjects, soy isoflavones as intervention, and arterial stiffness as primary outcome. A random-effects meta-analysis was used to pool estimates across studies. Standardized mean difference (SMD) was used to synthesize quantitative results.

RESULTS

Among 998 articles retrieved, 8 articles met our criteria. Duration of intervention was relatively short (maximum of 12 weeks). Outcome measurements extracted were pulse wave velocity (PWV), systemic arterial compliance (SAC), augmentation index (AI), and cardio-ankle vascular index (CAVI). Soy isoflavones reduced arterial stiffness compared to placebo (standardized mean difference - 0.33, 95% confidence interval - 0.47, - 0.19). Subgroup analyses showed no difference between treatment effects for intervention duration (< 6 weeks vs. ≥ 6 weeks) or gender (women only vs. men only vs. combined). Sensitivity analysis showed no difference in the effect of soy isoflavones between PWV, CAVI, SAC, and AI.

CONCLUSION

Supplementation of soy isoflavones reduced arterial stiffness. Longer duration trials with larger number of participants are warranted.

Large-Artery Stiffness in Health and Disease: JACC State-of-the-Art Review

A healthy aorta exerts a powerful cushioning function, which limits arterial pulsatility and protects the microvasculature from potentially harmful fluctuations in pressure and blood flow. Large-artery (aortic) stiffening, which occurs with aging and various pathologic states, impairs this cushioning function, and has important consequences on cardiovascular health, including isolated systolic hypertension, excessive penetration of pulsatile energy into the microvasculature of target organs that operate at low vascular resistance, and abnormal ventricular-arterial interactions that promote left ventricular remodeling, dysfunction, and failure. Large-artery stiffness independently predicts cardiovascular risk and represents a high-priority therapeutic target to ameliorate the global burden of cardiovascular disease. This paper provides an overview of key physiologic and biophysical principles related to arterial stiffness, the impact of aortic stiffening on target organs, noninvasive methods for the measurement of arterial stiffness, mechanisms leading to aortic stiffening, therapeutic approaches to reduce it, and clinical applications of arterial stiffness measurements.

Decreased arterial distensibility and postmeal hyperinsulinemia in young Japanese women with family history of diabetes

INTRODUCTION

To assess vascular function and characterize insulin secretion using a physiological approach in Japanese women with family history of type 2 diabetes (FHD).

RESEARCH DESIGN AND METHODS

Standardized mixed-meal tests were performed with multiple postprandial glucose, insulin and free fatty acids (FFA) measurements over a 30-120 min period in 31 Japanese women aged 21-24 years. Arterial distensibility was assessed as well.

RESULTS

Fasting glucose, triglyceride and insulin averaged <90 mg/dL, <60 mg/dL and <5 μU/mL, respectively, and did not differ cross-sectionally between 10 with (FHD+) and 21 without FHD (FHD-). FHD+ showed higher insulin responses not only during the first 30 min (p=0.005) but also during the second hour (60-120 min, p<0,05) in spite of identical postprandial suppression of FFA and identical fasting and postprandial glucose and FFA concentrations, except for higher 60 min FFA in FHD+. Further, FHD+ had decreased arterial distensibility (p=0.003). On multivariate regression analysis, arterial distensibility emerged as the only significant independent predictor of FHD+. Endurance training in FHD+ did not alter decreased arterial distensibility whereas it abolished postprandial hyperinsulinemia.

CONCLUSIONS

FHD was associated with decreased arterial distensibility and postprandial hyperinsulinemia despite nearly identical postprandial glycemia and postprandial FFA suppression, suggesting that impaired vascular insulin sensitivity may precede glucose and lipid dysmetabolism in normal weight Japanese women aged 22 years.

Effects of different intensities and durations of aerobic exercise training on arterial stiffness

[Purpose] In the present study, we investigated the effects of regular aerobic training with different intensities and durations on new indices of arterial stiffness measured via an upper-arm oscillometric device. [Participants and Methods] We gathered data from 41 middle-aged and older people (age 65.0 ± 11.7 years). Participants were randomly divided into five groups: (1) 15 minutes of low intensity aerobic training (n=10); (2) 30 minutes of low intensity training (n=7); (3) 15 minutes of moderate-intensity training (n=9); (4) 30 minutes of moderate-intensity training (n=8); and (5) a non-training group (n=7). Training was conducted for 8 weeks, three times per week. Arterial pulse wave index, arterial pressure-volume index, brachial-ankle and heart-brachial pulse wave velocity, cardio-ankle vascular index, brachial and ankle blood pressure, heart rate, and peak oxygen uptake were measured before and after the intervention. [Results] All indicators of arterial stiffness and brachial and ankle blood pressure in the exercise groups were significantly lower after versus before the intervention. Peak oxygen uptake did not differ before versus after the intervention. [Conclusion] The present findings indicate that regular aerobic exercise may be important in reducing arterial stiffness regardless of the intensity or duration of aerobic exercise.

Correlation Between the Cardio-Ankle Vascular Index and Renal Resistive Index in Patients With Essential Hypertension

Background

Renal resistive index (RRI) is a parameter determined by Doppler sonography that reflects renal hemodynamics. Significant relationships connecting increases in the RRI with cardiovascular risk factors and the incidence of cardiovascular disease in hypertensive patients have been reported. This cross-sectional study aimed to clarify the relationship between cardio-ankle vascular index (CAVI), a novel marker of arterial stiffness, and the RRI in patients with essential hypertension with the goal of primary prevention of cardiovascular disease.

Methods

The study included 245 patients undergoing treatment for essential hypertension (95 men and 150 women; mean age ± standard deviation, 65 ± 13 years) with no history of cardiovascular disease. The CAVI and RRI were measured using commercial devices, and their relationships to various clinical parameters were examined.

Results

A significant positive correlation was observed between the CAVI and RRI (r = 0.43, P < 0.001). Multiple regression analyses revealed a value of β of 0.28 (P < 0.001) when CAVI was evaluated as the independent and RRI as the dependent variable. Receiver-operating characteristic curve analysis indicated that the CAVI cutoff point for high RRI (> 0.70) was 9.0 with area under the curve of 0.700 (P < 0.001).

Conclusion

The results from this study indicate that the CAVI varies directly with measures of renal vascular hemodynamics (RRI) in patients with essential hypertension. These findings identified a cardiovascular risk value of the CAVI from the perspective of renal hemodynamics as 9.0 in this patient population.

The HOPE Asia Network activity for "zero" cardiovascular events in Asia: Overview 2020

The impact of hypertension-related cardiovascular disease and target organ damage, and therefore the benefits of blood pressure (BP) control, is greater in Asian than in Western countries. Asia-specific features of hypertension and its effective management are important and active areas of research. The Hypertension Cardiovascular Outcome Prevention and Evidence in Asia (HOPE Asia) Network was formed in 2016 and is now a member of the World Hypertension League. The main goal of the HOPE Asia Network is to improve the management of hypertension and organ protection toward achieving "zero" cardiovascular events in Asia. Considerable work has already been done on the journey to achieving this goal. We have shown that BP control status in Asia differs between countries, and even between regions within the same country. Several expert panel consensus recommendations and clinical guidance papers are available to support the use of home and ambulatory BP monitoring in the region. In addition, the AsiaBP@Home study prospectively investigated home BP control status across 15 specialist centers using the same validated device and measurement schedule. We have also proposed the concept of systemic hemodynamic atherothrombotic syndrome (SHATS), a vicious cycle of BP variability and vascular disease on cardiovascular events and organ damage, and suggested a SHATS score for risk stratification for clinical practice. This special issue of the journal collates Asia-specific resources and data, contributing to advances in hypertension management and cardiovascular disease prevention in the region.

Highly precise risk prediction model for new-onset hypertension using artificial intelligence techniques

Hypertension is a significant public health issue. The ability to predict the risk of developing hypertension could contribute to disease prevention strategies. This study used machine learning techniques to develop and validate a new risk prediction model for new-onset hypertension. In Japan, Industrial Safety and Health Law requires employers to provide annual health checkups to their employees. We used 2005-2016 health checkup data from 18 258 individuals, at the time of hypertension diagnosis [Year (0)] and in the two previous annual visits [Year (-1) and Year (-2)]. Data were entered into models based on machine learning methods (XGBoost and ensemble) or traditional statistical methods (logistic regression). Data were randomly split into a derivation set (75%, n = 13 694) used for model construction and development, and a validation set (25%, n = 4564) used to test performance of the derived models. The best predictor in the XGBoost model was systolic blood pressure during cardio-ankle vascular index measurement at Year (-1). Area under the receiver operator characteristic curve values in the validation cohort were 0.877, 0.881, and 0.859 for the XGBoost, ensemble, and logistic regression models, respectively. We have developed a highly precise prediction model for future hypertension using machine learning methods in a general normotensive population. This could be used to identify at-risk individuals and facilitate earlier non-pharmacological intervention to prevent the future development of hypertension.

Rationale, design, and baseline characteristics of the Cardiovascular Prognostic COUPLING Study in Japan (the COUPLING Registry)

Vascular biomarkers, including the cardio-ankle vascular index (CAVI), are increasingly being recognized as important indicators of cardiovascular risk. CAVI has been shown to have good discriminative ability for detecting new-onset hypertension, but results of studies investigating cardiovascular risk prediction are inconsistent. Furthermore, there is a lack of data on the prognostic value of changes in CAVI over time. The Cardiovascular Prognostic Coupling study was designed to determine the impact of baseline CAVI and changes in CAVI on cardiovascular events in a Japanese cohort. The design of the ongoing, multicenter, prospective, observational registry and baseline characteristics of the enrolled population are reported. Eligible consecutive patients were aged ≥30 years, had ≥1 cardiovascular risk factor, and were being treated according to relevant Japanese guidelines. The primary outcome is time to onset of a major cardiovascular event (a composite of cerebral infarction, cerebral hemorrhage, subarachnoid hemorrhage, stroke of unknown etiology, myocardial infarction, cardiovascular intervention for angina pectoris, and sudden death). Screening and enrollment occurred over a period of 3 years, followed by ≥7 years of follow-up, with CAVI determined annually. A total of 5279 patients were registered, of whom 5109 had baseline data available and will be included in future analyses. Mean CAVI at baseline was 8.8 ± 1.4. The proportion of patients with CAVI of <8, 8-10 or >10 was 25.3%, 57.0%, and 17.7%, respectively. Data from this registry should provide information on the significance of baseline CAVI and change in CAVI as indicators of cardiovascular prognosis in a representative patient population.

Brachial-Ankle Pulse Wave Velocity Versus Its Stiffness Index β-Transformed Value as Risk Marker for Cardiovascular Disease

Background

The difference in the predictive ability of the brachial‐ankle pulse wave velocity (baPWV) and its stiffness index β‐transformed value (β‐baPWV, ie, baPWV adjusted for the pulse pressure) for the development of pathophysiological abnormalities related to cardiovascular disease or future occurrence of cardiovascular disease was examined.

Methods and Results

In study 1, a 7‐year prospective observational study in cohorts of 3274 men and 3490 men, the area under the curve in the receiver operator characteristic curve analysis was higher for baPWV than for β‐baPWV for predicting the development of hypertension (0.73, 95% CI=0.70 to 0.75 versus 0.59, 95% CI=0.56 to 0.62; P<0.01) and/or the development of retinopathy (0.78, 95% CI=0.73 to 0.82 versus 0.66, 95% CI=0.60 to 0.71; P<0.01) by the end of the study period. During study 2, a 3‐year observation period on 511 patients with coronary artery disease, 72 cardiovascular events were confirmed. The C statistics of both markers for predicting the development of cardiovascular events were similar.

Conclusions

Stiffness index β transformation of the baPWV may attenuate the significance of the baPWV as a risk marker for development of pathophysiological abnormalities related to cardiovascular disease in male subjects.

Short-Term Prognostic Impact of Arterial Stiffness in Older Adults Without Prevalent Cardiovascular Disease

Arterial stiffness, represented as carotid-femoral pulse wave velocity (cfPWV), predicts cardiovascular disease (CVD). In older populations, however, this association seems attenuated. Moreover, the prognostic values of pulse wave velocity at different arterial segments and newer parameters like cardio-ankle vascular index (CAVI) remain unclear, especially in US older adults. In 3034 Atherosclerosis Risk in Communities (ARIC) study participants (66-90 years) without CVD, we examined the associations of 4 pulse wave velocity measures (cfPWV, heart-femoral, brachial-ankle, heart-ankle) and 2 new measures of arterial stiffness (CAVI and cardio-femoral vascular index derived from heart-ankle and heart-femoral, respectively) with incident CVD (coronary disease, stroke, and heart failure) and all-cause mortality. Over a median follow-up of 4.4 years, there were 168 incident CVD events and 244 deaths. Overall, stiffness measures did not show strong associations with CVD, except cfPWV, which demonstrated a J-shaped association even after adjusting for potential confounders (hazard ratio, 1.83 [95% CI, 1.08-3.09] in top quartile and 1.97 [1.14-3.39] in bottom quartile versus second bottom quartile). When each CVD was examined separately, heart failure was most robustly associated with higher cfPWV, and stroke was strongly associated with lower cfPWV. There were no significant associations with all-cause mortality. Among different measures of pulse wave velocity, cfPWV showed the strongest associations with CVD, especially heart failure, in older adults without CVD. Other pulse wave velocity measures had no strong associations. Our findings further support cfPWV as the index measure of arterial stiffness and the link of arterial stiffness to heart failure development but also suggest somewhat limited prognostic value of arterial stiffness in older adults overall.

Heart-Thigh Cuff Pulse Wave Velocity: A Novel Nontechnical Measure of Arterial Stiffness

BACKGROUND

Recently, a novel index of arterial stiffness was developed to eliminate the placements of transducers on the carotid and femoral arteries and to make the measurement substantially easier. We evaluated the agreement of this new methodology with the well-established carotid-femoral pulse wave velocity (cfPWV).

METHODS

A total of 50 adults (28 men and 22 women) varying widely in age and blood pressure were studied. Heart-thigh pulse wave velocity (htPWV) and cfPWV were measured and compared.

RESULTS

Mean values of cfPWV and htPWV were 713 ± 145 and 699 ± 150 cm/s and were not significantly different (P = 0.43). Both cfPWV and htPWV were significantly associated with age (r = 0.80 and 0.58), body mass index (r = 0.44 and 0.31), and systolic blood pressure (r = 0.42 and 0.41). The 2 pulse wave velocity measures demonstrated a strong linear association with a Pearson correlation coefficient of 0.64 (P < 0.001). This agreement was consistent with the results of the Bland-Altman plot.

CONCLUSION

The automatic htPWV method, which permits the data acquisition with minimum technical skill, time, and intrusion in an operator-independent fashion, has good potential as a screening device for assessing arterial stiffness in a clinical setting.

Skeletal muscle function and need for long-term care of urban elderly people in Japan (the Bunkyo Health Study): a prospective cohort study

PURPOSE

The proportion of elderly individuals (age ≥65 years) in Japan reached 27.7% in 2017, the highest in the world. A serious social problem in a super-aged society is the rise in the number of elderly people who need long-term care (LTC), which is mainly due to cerebrovascular disease, dementia, age-related frailty, falls and fractures, and joint disease. We hypothesised that decreased muscle mass, muscle strength and insulin sensitivity are the common risk factors for these diseases related to needing LTC. We developed a prospective cohort study of elderly subjects in an urban community to test this hypothesis. The primary objective is to prospectively investigate associations between muscle mass, muscle strength, and insulin sensitivity and incidence of main disease and risk factors of needing LTC. The primary outcomes are the incidence of cerebrovascular disease and cognitive decline.

PARTICIPANTS

Participants were 1629 people aged 65-84 years living in 13 communities in an urban area (Bunkyo-ku, Tokyo, Japan). Average age was 73.1±5.4 years.

FINDINGS TO DATE

We obtained baseline data on cognitive function, cerebral small vessel disease (SVD) determined by brain MRI, body composition, bone mineral density, arteriosclerosis, physical function, muscle mass, muscle strength and insulin sensitivity. Mild cognitive impairment and dementia were observed in 18.1% and 3.3% of participants, respectively. The prevalence of cerebral SVD was 24.8%. These characteristics are similar to those previously reported in elderly Japanese subjects.

FUTURE PLANS

We will ask participants about their health status, including incidence of cerebrovascular disease, falls, fractures and other diseases every year by mail. We plan to re-evaluate cognitive function, brain MRI parameters and other parameters at 5 and 10 years after the baseline evaluation. We will evaluate whether low muscle function (muscle mass, muscle strength or insulin sensitivity) is a risk factor for cognitive decline or cerebrovascular disease.

Cardio-ankle vascular index is associated with diabetic retinopathy in younger than 70 years patients with type 2 diabetes mellitus

AIMS

This study aimed to investigate the relationship between cardio-ankle vascular index (CAVI) and diabetic retinopathy (DR) in Caucasian patients with type 2 Diabetes Mellitus (T2DM).

METHODS

This was a cross-sectional study of 299 T2DM patients admitted to Endocrine Unit of Foggia. DR was diagnosed using the International Clinical Disease Severity Scale of American Academy of Ophthalmology. The VaSera VS-1500N was used to measure CAVI. Because age is the most powerful determinant of arterial stiffness and affects the progression of DR, we divided the whole sample into two subgroups: above (older) and below (younger) 70 years.

RESULTS

The mean age of patients was 60.4 ± 12.6 years and the mean CAVI value was 8.6 ± 1.7. In the whole population DR was diagnosed in 74 (24.7%) patients. CAVI value was clearly higher in patients with DR (9.5 ± 1.6) than in those without (8.7 ± 1.7) (P = 0.001) although this difference was not any more significant when adjusted by age and gender (P = 0.067). In the multivariate model taking into account several possible confounders, the correlation between DR and CAVI remained significant only in younger subjects. In the same subgroup we found a significant association between the stages of DR and CAVI (p = 0.019 adjusted by age and gender).

CONCLUSIONS

This study shows that CAVI is significantly higher in younger patients with DR than in those without, with a relationship between the stages of DR and CAVI in the same subgroup. Physicians should pay attention to sub-clinical macroangiopathy in younger T2DM patients who have DR.

Relationships Between the Cardio-Ankle Vascular Index and Pulsatility Index of the Common Carotid Artery in Patients With Cardiovascular Risk Factors

Background

Pulsatility index (PI) is a hemodynamic parameter determined using Doppler sonography; it reflects the degree of peripheral vascular resistance. Moreover, researchers have reported significant relationships between an increase in the PI of the common carotid artery (CCA) and ischemic stroke. This cross-sectional study aimed to clarify the relationships between cardio-ankle vascular index (CAVI) as a marker of arterial stiffness and the PI of the CCA in patients with cardiovascular risk factors for the primary prevention of ischemic stroke.

Methods

A total of 405 outpatients undergoing treatment for cardiovascular risk factors (152 men and 253 women; mean age ± standard deviation, 64 ± 9 years) with no history of cardiovascular events, including ischemic stroke, were enrolled. The CAVI and the PI of the CCA were measured using commercial devices, and their relationships to various clinical parameters were examined.

Results

A significant positive correlation was observed between the CAVI and the PI of the CCA (r = 0.44, P < 0.001). Further, multiple regression analysis revealed that the CAVI (β = 0.19, P < 0.001) was selected as independent factor for PI of the CCA as a subordinate factor. Meanwhile, high-sensitivity C-reactive protein, as an inflammation marker, and skin autofluorescence, as a marker of advanced glycation end products in the tissues, were selected as independent variables for either the CAVI or the PI of the CCA as a subordinate factor. The receiver-operating characteristic curve analysis indicated that the cut-off point of the CAVI for high PI of the CCA (> 1.60) as a risk value of stroke incidence by previous report was 9.1 (area under the curve = 0.750, P < 0.001).

Conclusion

The present results indicate that the CAVI reflects cerebrovascular resistance in patients with cardiovascular risk factors. Moreover, the risk value of the CAVI for ischemic stroke incidence was considered to be 9.1 in these patients.

Arterial Stiffness Assessed by Cardio-Ankle Vascular Index

Arterial stiffness is an age-related disorder. In the medial layer of arteries, mechanical fracture due to fatigue failure for the pulsatile wall strain causes medial degeneration vascular remodeling. The alteration of extracellular matrix composition and arterial geometry result in structural arterial stiffness. Calcium deposition and other factors such as advanced glycation end product-mediated collagen cross-linking aggravate the structural arterial stiffness. On the other hand, endothelial dysfunction is a cause of arterial stiffness. The biological molecular mechanisms relating to aging are known to involve the progression of arterial stiffness. Arterial stiffness further applies stress on large arteries and also microcirculation. Therefore, it is closely related to adverse outcomes in cardiovascular and cerebrovascular system. Cardio-ankle vascular index (CAVI) is a promising diagnostic tool for evaluating arterial stiffness. The principle is based on stiffness parameter β, which is an index intended to assess the distensibility of carotid artery. Stiffness parameter β is a two-dimensional technique obtained from changes of arterial diameter by pulse in one section. CAVI applied the stiffness parameter β to all of the arterial segments between heart and ankle using pulse wave velocity. CAVI has been commercially available for a decade and the clinical data of its effectiveness has accumulated. The characteristics of CAVI differ from other physiological tests of arterial stiffness due to the independency from blood pressure at the time of examination. This review describes the pathophysiology of arterial stiffness and CAVI. Molecular mechanisms will also be covered.

Relationships Between Skin Autofluorescence and Cardio-Ankle Vascular Index in Japanese Male Patients With Metabolic Syndrome

Background

An autofluorescence (AF) reader can be used to noninvasively measure tissues that accumulated advanced glycation end-products to diagnose skin AF. This study aimed to clarify the clinical significance of skin AF as a risk factor for cardiovascular disease in Japanese male patients with metabolic syndrome using the cardio-ankle vascular index (CAVI) as a marker of arterial function.

Methods

This cross-sectional study enrolled 261 Japanese male patients with metabolic syndrome without history of cardiovascular disease (mean age, 58 ± 7 years (mean ± standard deviation)). Associations between skin AF and various clinical parameters including CAVI were examined.

Results

Skin AF was significantly positively correlated with CAVI (r = 0.40, P < 0.001). Furthermore, multiple regression analyses revealed that skin AF (β = 0.18, P = 0.002) was selected as an independent subordinate factor for CAVI. Meanwhile, homeostatic model assessment of insulin resistance (HOMA-IR) as a marker of insulin resistance, smoking habits and high-sensitivity C-reactive protein as an inflammation marker were independent variables for either CAVI or skin AF as a subordinate factor. According to the receiver-operating characteristic curve analysis and results of previous reports that determined CAVI of ≥ 9.0 as a diagnostic criterion for vascular failure, skin AF of > 2.7 arbitrary unit is the optimal cut-off point for discriminating high CAVI (area under the curve = 0.718, P < 0.001).

Conclusion

Findings in this study indicate that skin AF may be an important risk factor of cardiovascular disease in Japanese male patients with metabolic syndrome. In addition, the risk value of skin AF was considered as higher than 2.7 arbitrary unit. Further investigations in a large number of prospective studies, including intervention therapies, are required to validate the results in this study.