Impact of Metabolic Syndrome on Brachial-Ankle Pulse Wave Velocity in Japanese

Prevalence and metabolic determinants of abnormal alanine aminotransferase: A cross-sectional study of Iranian adults, 2018-2022

BACKGROUND

Alanine aminotransferase (ALT) is an enzyme whose activity became the principal biomarker for liver disease. In the current study, we aimed to determine the prevalence of abnormal ALT, as a surrogate of nonalcoholic fatty liver disease (NAFLD) and its associated determinants using different criteria among Tehranian subjects between 2018 and 2022.

METHODS

This is a cross-sectional study on 5676 Tehranian individuals aged 20-70 years. The weighted prevalence of abnormal ALT was calculated using both the National Health and Nutrition Examination Survey in the United States (US-NHANCE; ALT ≥30 U/L for females and ≥40 U/L for males) and the American College of Gastroenterology (ACG) guideline (ALT >25 U/L for females, and >33 U/L for males) thresholds. Moreover, uni/multivariable logistic regression analysis was performed to find the determinants of abnormal ALT.

RESULTS

The weighted prevalence of abnormal ALT was 12.8% (7.6% females and 18% males) and 22.5% (17.7% females and 27.3% males) based on US-NHANCE and ACG criteria, respectively. Our results showed every decade increase in age decreased the risk of abnormal ALT by 32%. We also found that generally male gender, being overweight/obese, central adiposity, TG ≥6.9 mmol/L, non-HDL-C ≥3.37 mmol/L, lipid-lowering medications, pre-diabetes/T2DM were associated with abnormal ALT using different cutoff points. Moreover, among men resting tachycardia (≥90 beats per min), hypertension, and females past-smoker were also found as other determinants of abnormal ALT.

CONCLUSION

High prevalence of abnormal ALT among non-elderly Iranian adults, especially among men, necessitates immediate multifaceted strategies by policymakers to prevent potential complications caused by NAFLD.

Three-minute bench step exercise as a countermeasure for acute mental stress-induced arterial stiffening

Acute mental stress (MS) induces a transient increase in arterial stiffness. We verified whether a single bout of bench step (BS) exercise for 3 minutes counteracts acute MS-induced arterial stiffening. Fifteen healthy young men (mean age, 21.7 ± 0.3 years) underwent two experimental trials: rest (RE) and exercise (EX) trials. Following a 5-minute MS task, the participants in the RE trial rested on a chair for 3 minutes (from 10 to 13 minutes after task cessation), whereas those in the EX trial performed the BS exercise for the same duration. The heart-brachial pulse wave velocity (PWV) (hbPWV), brachial-ankle PWV (baPWV), heart-ankle PWV (haPWV), and the cardio-ankle vascular index (CAVI) were measured at baseline and at 5 and 30 minutes after the task. In both trials, significant increases in hbPWV, haPWV, and CAVI occurred at 5 minutes after the task; these elevations persisted until 30 minutes after the task in the RE trial, but significantly decreased to baseline levels in the EX trial. baPWV was significantly elevated at 30 minutes after the task in the RE trial, but not in the EX trial. This study reveals that a 3-minute BS exercise offsets acute MS-induced arterial stiffening.

Cardiac, Macro-, and Micro-Circulatory Abnormalities in Association With Individual Metabolic Syndrome Component: The Northern Shanghai Study

Objective: This study investigated the association of metabolic syndrome (MS) and its components with cardiac, macro-, and micro-circulatory abnormalities in an elderly Chinese population.

Methods: This cross-sectional study was conducted using data for 1,958 participants from the Northern Shanghai Study aged over 65 years without a history of cardiovascular disease. MS was defined according to the National Cholesterol Education Program Adult Treatment Panel III in 2005 (NCEPIII 2005). Asymptomatic cardiovascular impairment parameters, including the left ventricle mass index (LVMI), peak transmitral pulsed Doppler velocity/early diastolic tissue Doppler velocity (E/Ea), carotid-femoral pulse wave velocity (cf-PWV), ankle-brachial index (ABI), carotid intima-media thickness (CIMT), arterial plaque, and urinary albumin–creatinine rate (UACR), were evaluated.

Results: LVMI, E/Ea, cf-PWV, and the proportion of UACR > 30 mg/g exhibited increasing trends while ABI exhibited a decreasing trend according to the number of MS components (all p for trend < 0.01). Logistic regression analysis revealed that MS was significantly associated with LV hypertrophy (LVH), LV diastolic dysfunction, arteriosclerosis, and microalbuminuria (all p < 0.001). Central obesity and high blood pressure were associated with all cardiovascular abnormalities (all p < 0.05), whereas elevated plasma glucose was associated with arteriosclerosis and microalbuminuria (both p < 0.001). In addition, high triglyceride levels were associated with microalbuminuria (p < 0.05).

Conclusions: MS is significantly associated with cardiac, macro-, and micro-circulatory abnormalities in elderly Chinese. Moreover, the presence of individual MS components may have specific prognostic significance.

Hepatic Steatosis Index and Chronic Kidney Disease among Middle-Aged Individuals: A Large-Scale Study in Japan

BACKGROUND

Though nonalcoholic fatty liver disease (NAFLD) is related to chronic kidney disease (CKD), it is unclear whether the hepatic steatosis index (HSI), a screening tool for NAFLD, is related to CKD. The present study investigated the relationship between HSI and CKD among middle-aged individuals in Japan.

METHODS

Subjects were adults (aged 40-64 years) who received an annual health checkup in Japan between April 2013 and March 2014. Height and weight were measured, and venous blood samples were obtained to determine alanine aminotransferase (ALT), aspartate aminotransferase (AST), and creatinine levels. HSI was calculated by the following formula: HSI = 8 × ALT/AST ratio + body mass index (+2, if diabetes; +2, if female). CKD was defined as an estimated glomerular filtration rate < 60 mL/min/1.73 m2 and/or urinary protein of ≥ (+). Logistic regression analysis was performed to estimate the odds ratio (OR) and its 95% confidence interval (CI) for CKD.

RESULTS

Data of 94,893 adults were analyzed. Compared with men with an HSI < 30, men with 30 ≤ HSI ≤ 36 (OR: 1.50, 95% CI: 1.40-1.61) and HSI > 36 (OR: 2.14, 95% CI: 1.99-2.31) had significantly higher ORs for CKD. Moreover, there was a significant dose-response relationship between HSI and CKD (P for trend < 0.001). Even after adjusting for confounders, the significant results persisted. These findings in men were similar to those in women.

CONCLUSIONS

This study showed that the HSI was associated with CKD among middle-aged adults in Japan. Additionally, a dose-response relationship of HSI to CKD was observed. The present study suggested that it might be useful to monitor the HSI among middle-aged individuals to detect CKD at an early stage.

Association between arterial stiffness and the clustering of metabolic syndrome risk factors: a systematic review and meta-analysis

OBJECTIVES

Metabolic syndrome (MetS) is a cluster of different cardiometabolic risk factors (CMRFs), and its different combinations with other CMRFs, such as arterial stiffness have been hypothesized to explain, at least partially, increased risk of cardiovascular disease. Thus, in this systematic review and meta-analysis, we aimed to synthesize the evidence regarding the association between the clustering of MetS-related CMRFs and arterial stiffness measured using pulse wave velocity (PWV).

METHODS

Original studies analysing the association between arterial stiffness, measured using PWV, and MetS were systematically searched. Pooled effect size estimates and their respective 95% confidence intervals (CI) were calculated using the DerSimonian and Laird method for two separate analyses: the diagnosis of MetS and PWV values and the number of CMRFs and PWV values.

RESULTS

Moderate effect size estimates were observed between MetS and PWV (0.68, 95% CI: 0.54-0.82) with a slightly higher effect size for the low-risk compared with the high-risk population group (0.75, 95% CI: 0.58-0.92; and 0.51, 95% CI: 0.32-0.82, respectively). A trend between the number of MetS-related CMRFs and PWV was found with the pooled effect size nearly doubling as the number of MetS-related CMRFs increased, 0.11 (95% CI: 0.04-0.17) for one MetS-related CMRF, 0.26 (95% CI: 0.13-0.4) for two, and 0.4 (95% CI: 0.2-0.6) for three or more.

CONCLUSION

These results demonstrated a clinically relevant association between MetS and PWV and an increasing trend in PWV values, such as a MetS-related CMRF increase. Although these results should be considered cautiously because of the considerable heterogeneity, our findings reinforce the rationale of MetS as an aggregation of risk factors with common causes, which could provide additional useful information to guide clinical management.

Impact of acute mental stress on segmental arterial stiffness

PURPOSE

It has been reported that acute brief episodes of mental stress (MS) result in a prolonged increase in carotid-femoral pulse wave velocity (cfPWV), an index of aortic stiffness. However, whether acute MS also impacts arterial stiffness in other segments is unclear. The present study aimed to examine the impact of acute MS on segmental arterial stiffness.

METHODS

In the main experiment, 17 young male subjects (mean age, 20.1 ± 0.7 years) performed a 5-min MS and control (CON) task in a random order. Pulse wave velocity (PWV) from the heart to the brachium (hbPWV) and the ankle (haPWV), PWV between the brachial artery and the ankle (baPWV), and the cardio-ankle vascular index (CAVI) were simultaneously measured at baseline and 5, 15, and 30 min after the task.

RESULTS

Compared to baseline values, hbPWV, baPWV, haPWV, and CAVI significantly increased until 30 min after the MS task, whereas these variables did not significantly change following the CON task. At 5 and 30 min after the MS task, percentage changes from baseline were significantly higher in hbPWV (+ 5.2 ± 4.4 and 6.6 ± 4.9%) than in baPWV (+ 2.2 ± 2.1 and 2.2 ± 2.0%) or haPWV (+ 3.6 ± 2.6 and 4.3 ± 2.9%) and were also significantly lower in baPWV than in haPWV.

CONCLUSION

These findings suggest that acute MS elicits an increase in arterial stiffness in various segments and this arterial stiffening is not uniform among the segments.

The association of metabolic syndrome and its components with brachial-ankle pulse wave velocity in south China

BACKGROUND

Brachial-ankle pulse wave velocity (baPWV) can reflect both central and peripheral arterial stiffness. Metabolic syndrome (MS) and its components may increase arterial stiffness and the risks of cardiovascular diseases. However, the correlation of MS and its components with arterial stiffness has not been not well studied. The aim of this study was to investigate the correlation between MS/its components and arterial stiffness by the measurement of baPWV in south China population.

METHODS

A total of 8599 subjects were selected from those who underwent health examination in our hospital. MS was defined by Joint Scientific Statement. BaPWV, waist circumference, blood pressure (BP), fasting plasma glucose (FPG), lipid profile and serum uric acid (UA) were measured. The relationship between baPWV and MS/its components was analyzed.

RESULTS

BaPWV was significantly higher in the subjects with MS than in those without MS (P < 0.001 for both genders). By multivariate regression analysis, all the metabolic components were correlated to baPWV in the male and female subjects except low HDL-C and high UA in the male group. BP and FPG had the strongest correlation factors. The values of baPWV were positively correlated with the advanced age (P < 0.001) and the values of the MS components, and this correlation was stronger in the females than in the males (P < 0.001).

CONCLUSION

Metabolic syndrome and its individual components were positively correlated with baPWV. Monitoring baPWV is helpful to identify early stage of arterial stiffness in those people with MS.

HIV is an independent predictor of aortic stiffness

BACKGROUND

Patients with treated Human Immunodeficiency Virus-1 (HIV) infection are at increased risk of cardiovascular events. Traditionally much of this risk has been attributed to metabolic and anthropometric abnormalities associated with HIV, which are similar to the metabolic syndrome (MS), an established risk factor for cardiovascular mortality. It remains unclear whether treated HIV infection is itself associated with increased risk, via increase vascular stiffness.

METHODS

226 subjects (90 with HIV) were divided into 4 groups based on HIV and MS status: 1) HIV-ve/MS-ve, 2) HIV-ve/MS + ve, 3) HIV + ve/MS-ve and 4)HIV + ve/MS + ve. CMR was used to determine aortic pulse wave velocity (PWV) and regional aortic distensibility (AD).

RESULTS

PWV was 11% higher and regional AD up to 14% lower in the HIV + ve/MS-ve group when compared to HIV-ve/MS-ve (p < 0.01 all analyses). PWV and AD in the HIV + ve/MS-ve group was similar to that observed in the HIV-ve/MS + ve group (p > 0.99 all analyses). The HIV + ve/MS + ve group had 32% higher PWV and 30-34% lower AD than the HIV-ve/MS-ve group (all p < 0.001), and 19% higher PWV and up to 31% lower AD than HIV + ve/MS-ve subjects (all p < 0.05). On multivariable regression, age, systolic blood pressure and treated HIV infection were all independent predictors of both PWV and regional AD.

CONCLUSION

Across multiple measures, treated HIV infection is associated with increased aortic stiffness and is also an independent predictor of both PWV and regional AD. The magnitude of the effect of treated HIV and MS are similar, with additive detrimental effects on central vascular elasticity.

Brachial-to-ankle pulse wave velocity as an independent prognostic factor for ovulatory response to clomiphene citrate in women with polycystic ovary syndrome

Background

Polycystic ovary syndrome (PCOS) has a risk for cardiovascular disease. Increased arterial stiffness has been observed in women with PCOS. The purpose of the present study was to investigate whether the brachial-to-ankle pulse wave velocity (baPWV) is a prognostic factor for ovulatory response to clomiphene citrate (CC) in women with PCOS.

Methods

This study was a retrospective cohort study of 62 women with PCOS conducted from January 2009 to December 2012 at the university hospital, Yamagata, Japan. We analyzed 62 infertile PCOS patients who received CC. Ovulation was induced by 100 mg CC for 5 days. CC non-responder was defined as failure to ovulate for at least 2 consecutive CC-treatment cycles. The endocrine, metabolic, and cardiovascular parameters between CC responder (38 patients) and non-responder (24 patients) groups were analyzed.

Results

In univariate analysis, waist-to-hip ratio, level of free testosterone, percentages of patients with dyslipidemia, impaired glucose tolerance, and diabetes mellitus, blood glucose and insulin levels at 60 min and 120 min, the area under the curve of glucose and insulin after 75-g oral glucose intolerance test, and baPWV were significantly higher in CC non-responders compared with responders. In multivariate logistic regression analysis, both waist-to-hip ratio (odds ratio, 1.77; 95% confidence interval, 2.2–14.1; P = 0.04) and baPWV (odds ratio, 1.71; 95% confidence interval, 1.1–2.8; P = 0.03) were independent predictors of ovulation induction by CC in PCOS patients. The predictive values of waist-to-hip ratio and baPWV for the CC resistance in PCOS patients were determined by the receiver operating characteristic curves. The area under the curves for waist-to-hip ratio and baPWV were 0.76 and 0.77, respectively. Setting the threshold at 0.83 for waist-to-hip ratio offered the best compromise between specificity (0.65) and sensitivity (0.84), while the setting the threshold at 1,182 cm/s for baPWV offered the best compromise between specificity (0.80) and sensitivity (0.71).

Conclusions

Both metabolic and cardiovascular parameters were predictive for CC resistance in PCOS patients. The measurement of baPWV may be a useful tool to predict ovulation in PCOS patients who receive CC.

Development of a novel pulse wave velocity measurement system: using dual piezoelectric elements

The aim of this study is to develop a painless system of measuring the brachial-ankle arterial pulse wave velocity (baPWV) without compression cuffs. The PWV reflects the compliance of the artery and is measured for the early diagnosis of arteriosclerotic vascular diseases. However, the conventional baPWV system, which measures four cuff pressures simultaneously, easily causes circulation block and tightening pain at the extremities. In addition, approximately 15 min are required to stabilise the blood pressure for re-examination. Therefore, we developed a novel baPWV measurement system using dual piezoelectric sensor elements. The principle of this high-sensitivity pressure pulse detection system is based on adding the two in-phase outputs from the coaxially arranged dual piezoelectric sensor. As our system facilitates the measurement of the baPWV by detecting the pulsation of an artery using sensors fixed on the skin where the pulse is palpable, it does not cause pain and reduces examination time. The coefficients of correlation between the baPWV values obtained from the conventional and present methods were 0.93 (right side) and 0.90 (left side). The results suggest that our system can be used to measure the baPWV without pressure cuffs as accurately as the conventional method.

Variation of serum monocyte chemoattractant protein-1 in patients with diabetes and metabolic syndrome

This study investigated the variation of serum monocyte chemoattractant protein-1 (MCP-1) in patients with both diabetes mellitus (DM) and metabolic syndrome (MS). Based on the International Diabetes Federation (IDF) diagnostic criteria, 93 patients enrolled in this study were divided into four groups: normal control (NC), simple DM, simple MS, and DM plus MS (DM-MS) groups. The main measures included height, weight, waist circumference (WC), hip circumference, blood pressure, fasting blood glucose, insulin resistance index (HOMA-IR), serum triglyceride (TG), HDL-ch, LDL-ch, and MCP-1. The results showed that the serum levels of MCP-1 in the DM-MS group were significantly increased as compared with those in the DM and MS groups (P<0.05), and the increase in the MCP-1 level in the DM group was much higher than in the MS group (P<0.05). The DM-MS group had the highest HOMA-IR levels, followed by MS, DM and NC groups (P<0.05). Correlation tests showed that the association of MCP-1 with age, HDL-ch, or LDL-ch was insignificant, whereas that of MCP-1 with body mass index (BMI), waist hip rate (WHR), WC, systolic blood pressure (SBP), diastolic blood pressure (DBP), TG, and HOMA-IR was significantly positive. It was concluded that circulating MCP-1 was substantially increased in patients with both DM and MS as compared with that in the patients with DM or MS alone, and the central obese state may contribute to a more vicious proinflammatory condition and insulin resistance in patients with diabetes.

Brachial-ankle pulse wave velocity and cardiovascular risk factors in the non-diabetic and newly diagnosed diabetic Chinese: Guangzhou Biobank Cohort Study-CVD

BACKGROUND

Increased arterial stiffness is an important cause of cardiovascular disease (CVD). We examined determinants of arterial stiffness in subjects across strata of glycaemic status.

METHODS

A total of 1249 subjects from a sub-study of the Guangzhou Biobank Cohort Study (GBCS-CVD) had brachial-ankle pulse wave velocity (baPWV) measured by automatic oscillometric method. Major cardiovascular risk factors including glycosylated haemoglobin A1c (HbA(1c)), high sensitivity C-reactive protein (hsCRP), fasting triglyceride, low- and high-density lipoprotein cholesterol and both fasting and post 2-h oral glucose-load glucose, systolic and diastolic blood pressure were assessed.

RESULTS

In all, 649, 479 and 121 subjects were classified into normoglycaemia, impaired glucose metabolism (IGM) and newly diagnosed diabetes groups, respectively. Both age and systolic blood pressure were significantly associated with increased baPWV in all three groups (all p < 0.001). In both normoglycaemic and IGM groups, hsCRP and HbA(1c) were positively associated with baPWV (p from 0.04 to < 0.001), whereas current smoking and triglyceride were associated with baPWV in the normoglycaemic and IGM group, respectively (p = 0.04 and 0.001). No gender difference in baPWV was observed in the normoglycaemic or IGM groups. However, in the newly diagnosed diabetes group, men had higher baPWV than women (p = 0.01).

CONCLUSIONS

In the normoglycaemic and IGM subjects, after adjusting for age, blood pressure and other confounders, increasing HbA(1c) was associated with increased baPWV, suggesting a pathophysiological role of chronic glycaemia that can contribute to vascular disease risk in persons without diabetes.

The relation of metabolic syndrome according to five definitions to cardiovascular risk factors--a population-based study

BACKGROUND

Although National Cholesterol Education Program (NCEP), International Diabetes Federation (IDF), American Heart Association and National Heart, Lung and Blood Institute (AHA/NHLBI), World Health Organization (WHO), and the European Group for the Study of Insulin Resistance (EGIR) definitions of metabolic syndrome (MetS) have been commonly used by studies, little is known about agreement among these five definitions. We examined the agreement among these five definitions and explored their relationship with risk factors of cardiovascular disease in a Taiwan population.

METHODS

A total of 1305 subjects aged 40 years and over in Taiwan were analyzed. Biomedical markers and anthropometric indices were measured. Agreement among definitions was determined by the kappa statistic. Logistic regression models were fit to estimate the odds of a high cardiovascular risk group for five definitions of MetS.

RESULTS

The agreement among the NCEP, IDF, and AHA/NHLBI definitions was from substantial to very good, and agreement between the WHO and EGIR definitions was also substantial. All MetS definitions were significantly associated prevalence of microalbuminuria, elevated highly sensitive CRP (hs-CRP), and arterial stiffness only in women. In men, MetS by NCEP and AHA/NHLBI was associated with elevated level of hs-CRP and arterial stiffness. MetS by WHO and EGIR were significantly associated with microalbuminuria. And MetS by WHO was the only MetS definition that significantly associated with prevalence of arterial stiffness (OR: 2.75, 95% CI: 1.22-6.19).

CONCLUSIONS

The associations of these five definitions with cardiovascular risk factors were similar in women, and it was evident that the five definitions performed better in women than in men, with higher ORs observed in relation to arterial stiffness, elevated hs-CRP, and higher Framingham risk scores.

Impact of lifestyle-related diseases on carotid arterial wall elasticity as evaluated by an ultrasonic phased-tracking method in Japanese subjects

AIM

We investigated the relationship between coronary risk factors and the intima-media thickness (IMT) and wall elasticity of carotid arteries. A new real-time ultrasonic measurement system that allows measurement of the elasticity of the carotid arterial intima-media complex was applied to 350 subjects, who were also checked for the presence/absence of hypertension, dyslipidemia, diabetes mellitus and regular smoking. Simultaneous measurement of the elastic modulus and IMT was conducted at four sites in the bilateral carotid arteries.

METHODS AND RESULTS

In the group with maximum IMT (max IMT) <1.1 mm, the IMT, as well as the mean elastic modulus in the circumferential direction (Etheta), showed positive correlations with age and coronary risk factors. Multiple regression analysis showed that age, systolic blood pressure and pulse rate remained independent determinants of Etheta. The number of criteria fulfilling the diagnosis of metabolic syndrome showed a good positive correlation with the value of Etheta in the group with max IMT values <1.1 mm.

CONCLUSION

Measurement of carotid arterial wall elasticity together with IMT is useful to detect dis-tortions in intramural elasticity distribution occurring in the early stages of atherosclerosis.

The metabolic syndrome and its traits as risk factors for subclinical atherosclerosis

CONTEXT AND OBJECTIVE

The metabolic syndrome (MetS) indicates an increased cardiovascular risk. The objective of the present study was to determine the impact of the MetS and its individual traits on subclinical atherosclerosis, as measured with six noninvasive measurements of atherosclerosis (NIMA) in a 50- to 70-yr-old Dutch population-based cohort. Furthermore, we determined the impact of three different definitions of the MetS.

DESIGN

We performed NIMA in 1517 participants of the Nijmegen Biomedical Study. The MetS was defined by definitions of the National Cholesterol Education Program, International Diabetes Federation, and the World Health Organization.

RESULTS

Participants with the MetS (National Cholesterol Education Program) were characterized by increased subclinical atherosclerosis compared with participants without any trait of the MetS, as reflected by lower ankle-brachial index at rest [percent change (95% confidence interval), M: -5.2% (-9; -1), F: -3.1% (-6; -1)] and after exercise [M: -7.7% (-17;+2), F: -6.6% (-11; -2)], higher augmentation index [M: +4.8% (+3; +7), F: +1.9% (+4; +18)], increased pulse wave velocity [M: +22.8% (+15;+32), F: +20.5% (+14; +28)], increased intima-media thickness [M: +9.3% (+5; +13), F: +6.9% (+3; +11)], and thicker plaques [M: +17.6% (-2; +41), F: +26.6% (+5; +53)]. Most intriguingly, the number of traits was strongly associated with the severity of subclinical atherosclerosis because all NIMA gradually deteriorated with increasing number of traits present; NIMA were already deteriorated when one or two traits were present and further deteriorated when four or five traits of the MetS were present. Similar result were found when International Diabetes Federation and World Health Organization definitions of the MetS were used.

CONCLUSIONS

For cardiovascular risk prediction, it is more important to take into account the presence of each individual trait and the number of traits of the MetS than to diagnose the presence of the MetS.

In addition to insulin resistance and obesity, brachial-ankle pulse wave velocity is strongly associated with metabolic syndrome in Chinese--a population-based study (Taichung Community Health Study, TCHS)

AIM

To investigate the association between arterial stiffness (present with brachial-ankle pulse wave velocity (baPWV)) and metabolic syndrome (MetS) in a population-based study of middle-aged Chinese.

METHODS

MetS was defined using the AHA/NHLBI criteria. A total of 1,018 subjects aged 40 years and over were recruited in 2004. Homeostasis model assessment was applied to estimate the degree of insulin resistance (HOMA-IR). The baPWV was divided into four groups by quartiles.

RESULTS

The prevalence of MetS and its individual components increased by the increase in baPWV quartiles. After adjusting for age, BMI, HOMA-IR, smoking, alcohol drinking, betel nut chewing, and physical activity status, multiple logistic regression revealed that baPWV groups were significantly associated with MetS. Compared with the lowest baPWV quartile, the adjusted odds ratio of having MetS in baPWV quartile II, III, IV was 2.10 (1.034.28), 4.48 (2.169.26), 10.4 (4.5324.0) in men, and 4.20 (1.4712.0), 14.6 (5.2240.6), 16.3 (5.4848.2) in women, respectively. The prevalence of MetS increased with the increase of age, HOMA-IR, and BMI groups. The optimal cut-off values of baPWV for MetS were 1,539 cm/sec in men and 1,482 cm/sec in women, respectively.

CONCLUSIONS

In addition to insulin resistance and obesity, baPWV was strongly related to MetS in middle-aged Taiwan Chinese. The cut-off value of baPWV for cardiovascular disease differed between genders.

Availability of cardio-ankle vascular index (CAVI) as a screening tool for atherosclerosis

BACKGROUND

A novel index, the cardio-ankle vascular index (CAVI), which reflects the stiffness of the aorta, femoral artery, and tibial artery, was recently developed by measuring brachial - ankle pulse wave velocity and blood pressure.

METHODS AND RESULTS

In the present study 1,014 Japanese adults from the general population were screened to clarify the correlation between CAVI and other existing markers related to atherosclerosis, including carotid intima - media thickness (CIMT) and homocysteine (HCY). CAVI was strongly associated with age in both men and women. After adjustment for age and sex, CAVI was correlated with systolic and diastolic blood pressures. In addition, CAVI was significantly correlated with total cholesterol hemoglobin A(1c) and total HCY, as well as CIMT.

CONCLUSION

CAVI is an appropriate screening tool for atherosclerosis, but further studies are needed to establish a convenient and effective screening system using it.

Arterial stiffness in diabetes and the metabolic syndrome: a pathway to cardiovascular disease

Increased arterial stiffness associated with diabetes and the metabolic syndrome may in part explain the increased cardiovascular disease risk observed in these conditions. Arterial stiffness can be estimated by quantifying pulse pressure but is better described by distensibility and compliance coefficients, pulse wave velocity and wave reflection. The most common non-invasive methodologies used to quantify these estimates of arterial stiffness (e.g. ultrasonography and applanation tonometry) are also described. We then review and summarise the current data on the associations between diabetes, the metabolic syndrome and insulin resistance on the one hand and greater arterial stiffness on the other, and identify and discuss some unresolved issues such as differential stiffening of central vs peripheral arterial segments, the impact of sex, and the pathobiology of increased arterial stiffness in diabetes and the metabolic syndrome. Finally, some considerations with regard to treatment options are presented. At present the most powerful therapy available for reducing arterial stiffness is to vigorously treat hypertension using pharmacological agents. New pharmacological strategies to reduce arterial stiffness are likely to be especially relevant to individuals with diabetes.

An association between decreased estimated glomerular filtration rate and arterial stiffness

OBJECTIVE

Chronic kidney disease (CKD) is a major public health problem, but there is controversy over whether or not CKD is an independent risk factor for peripheral arterial stiffness in community residents.

PATIENTS AND METHODS

We randomly recruited 107 men, aged 68+/-9 (mean +/- standard deviation) years, and 203 women, aged 67+/-7 years during their annual health examination in a single community. Study subjects did not have a clinical history of cerebrovascular disease or current neurological abnormalities. Peripheral arterial stiffness was evaluated by mean pulse wave velocity (PWV) determined at three points: from heart to the carotid artery, to the brachial artery, and to the ankle, and CKD was evaluated by estimated glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease Study Group equation.

RESULTS

Estimated GFR was significantly correlated with mean PWV (r=-0.317, p<0.001). Stepwise multiple linear regression analysis using mean PWV as an objective variable, adjusted by explanatory variables, showed that eGFR (beta,-0.171; p<0.001) significantly contributed to mean PWV, along with age, body mass index, systolic blood pressure, diastolic blood pressure, and antihypertensive drug use, and improved multiple coefficient of determination in the model.

CONCLUSION

Decreased eGFR is associated with an increased risk of arterial stiffness in community residents.

Arterial stiffness: clinical relevance, measurement and treatment

Most traditional cardiovascular risk factors alter the structure and/or function of arteries. An assessment of arterial wall integrity could therefore allow accurate prediction of cardiovascular risk in individuals. The term 'arterial stiffness' denotes alterations in the mechanical properties of arteries, and much effort has focused on how best to measure this. Pulse pressure, pulse wave velocity, pulse waveform analysis, localized assessment of blood vessel mechanics and other methods have all been used. We review the methodology underlying each of these measures, and present an evidence-based critique of their relative merits and limitations. An overview is also given of the drug therapies that may prove useful in the treatment of patients with altered arterial mechanics.

Relationship between cardio-ankle vascular index (CAVI) and carotid atherosclerosis in patients with essential hypertension

Aortic stiffness measured by aorta-iliac or carotid-femoral pulse wave velocity (PWV) predicts all-cause and cardiovascular mortality. Brachial-ankle PWV (baPWV) has been developed as a more convenient assessment of arterial stiffness. However, the problem with clinical use of baPWV is that the index itself is closely dependent on blood pressure. Recently, a new method, termed the cardio-ankle vascular index (CAVI), has been proposed in Japan to overcome the disadvantages associated with measuring PWV. However, its clinical usefulness has not yet been fully clarified. In the present study, we compared the usefulness of CAVI with that of ultrasound for evaluating atherosclerosis in patients with essential hypertension. CAVI was measured in 70 hypertensive patients. The intima-media thickness (IMT), cross-sectional distensibility coefficient (CSDC), stiffness parameter beta, and mean diastolic (V(d)) and systolic (V(s)) flow velocities were evaluated by carotid ultrasound. The V(d)/V(s) ratio, an index of peripheral arterial resistance, was also calculated. CAVI was positively correlated with IMT (r=0.360, p=0.0022) and stiffness beta (r=0.270, p=0.0239) and negatively correlated with V(d)/V(s) (r=-0.471, p<0.0001) and CSDC (r=-0.315, p=0.0079). Stepwise regression analysis revealed that age (r=0.475, p<0.0001) and pulse pressure (r=0.492, r<0.0001) were independent determinants of CAVI. These results suggest that CAVI is a useful clinical marker for evaluating atherosclerosis and arteriolosclerosis in patients with essential hypertension.

Insulin Resistance Is Associated with Arterial Stiffness Independent of Obesity in Male Adolescents

To determine the relationship between insulin resistance (IR) and arterial stiffness independent of obesity in male adolescents, we evaluated body fat, lipid parameters, indices of IR (fasting insulin, and the homeostasis model assessment of insulin resistance [HOMA-IR]), indices of insulin sensitivity (IS) (fasting glucose/fasting insulin [GF/IF], and the quantitative insulin sensitivity check index [QUICKI]), and lifestyle parameters in 256 male adolescents. We divided the study group into the following four subgroups based on the median value of HOMA-IR and obesity: non-obese with IS, non-obese with IR, obese with IS, and obese with IR. In order to estimate arterial stiffness, we measured brachial ankle pulse wave velocity (baPWV). Despite having a high body mass index (BMI), obese-IS adolescents showed a significantly lower fasting insulin and baPWV, but had higher IS indices than non-obese-IR adolescents. After an adjustment for age, BMI, waist-to-hip ratio, mean blood pressure, heart rate, total cholesterol level, triglyceride, alanine aminotransferase (ALT) level, physical activity, and television and computer usage, multiple regression models showed that baPWV was independently correlated with IR and IS indices. In conclusion, our results demonstrate an association between IR and baPWV independent of weight, suggesting that IR is a risk factor for the development of early atherosclerosis. Interventions that decrease IR in addition to weight reduction may be necessary to alter the early development of cardiovascular risk.

Blood Pressure Categories and Cardiovascular Risk Factors in Japan: The Jichi Medical School (JMS) Cohort Study

Few studies have reported on risk factors by blood pressure categories based on antihypertensive treatment in the general population. We examined the associations between blood pressure categories and other risk factors in Japan. Cross-sectional study, multicenter population-based study was designed. A total of 11,302 men and women were eligible. Data were obtained from April 1992 to July 1995 in 12 rural districts in Japan. Subjects were divided into three categories: normotensives (with blood pressure <140/90 mmHg), treated hypertensives (antihypertensive treatment regardless of current blood pressure), and nontreated hypertensives (blood pressure >or=140/90 mmHg without hypertensive treatment). The proportions of normotensives, treated hypertensives, and nontreated hypertensives were 63%, 10%, and 27% among men, and 67%, 13%, and 20% among women, respectively. Total cholesterol, triglyceride, blood glucose, and body mass index were higher in treated or nontreated hypertensives than in normotensives. Fibrinogen, factor VIIc, and physical activity index were higher in treated hypertensives than in normotensives. High-density lipoprotein (HDL) cholesterol was higher in normotensives than in treated or nontreated hypertensives in women; but no tendency was shown in men. The proportions of dyslipidemia, impaired glucose tolerance, and metabolic syndrome were significantly higher in treated and nontreated hypertensives than in normotensive men and women. In conclusion, cardiovascular risk factors were higher in hypertensives with or without treatment than in normotensives in a general population in Japan.

Left Ventricular Diastolic Dysfunction as Assessed by Echocardiography in Metabolic Syndrome

The purpose of the present study was to elucidate the cardiac structure and function in patients who have metabolic syndrome but no history of cardiovascular disease by analyzing echocardiographic findings. Echocardiographic examination was performed to screen for cardiovascular disease in 135 patients who were in their sixties. Patients were divided into metabolic syndrome (n=65, age: 65+/-2.7 years) and non-metabolic syndrome (n=70, age: 66+/-2.5 years) groups based on the criteria for metabolic syndrome proposed by the Japanese Society of Hypertension and seven other societies in 2005. The left ventricular (LV) wall thickness and dimension were measured by M-mode echocardiography. The relative wall thickness, LV mass index, and LV ejection fraction (LVEF) were calculated. LV diastolic function was assessed by the peak velocity of early rapid filling (E velocity) and the peak velocity of atrial filling (A velocity), and the ratio of E to A (E/A) was assessed by the transmitral flow. The Tei index, which reflects both LV diastolic and systolic function, was also calculated. There were no differences in relative wall thickness, LV mass index, or LVEF between the two groups. However, both the EIA and Tei index were significantly different between the metabolic syndrome (0.66+/-0.14 and 0.36+/-0.07, respectively) and non-metabolic syndrome (0.88+/-0.25 and 0.29+/-0.09) groups (p<0.001). These results indicate that patients with metabolic syndrome can have cardiac diastolic dysfunction even if they have neither LV hypertrophy nor systolic dysfunction.