Non-invasive assessment of cardiovascular disease in diabetes mellitus

Effectiveness of exercise training on arterial stiffness and blood pressure among postmenopausal women: a systematic review and meta-analysis

BACKGROUND

The acute and long-term benefits of exercise training on cardiovascular health have been well established. The systematic review and meta-analysis aimed to systematically assess the effectiveness of exercise training on arterial stiffness and blood pressure among postmenopausal women with elevated blood pressure.

METHODS

A comprehensive search was conducted on PubMed, Embase, Web of Science, ProQuest, Cochrane Library, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov website from inception to September 30, 2023, to identify the randomized controlled trials (RCTs), which evaluated the effectiveness of exercise training on arterial stiffness and blood pressure in postmenopausal women. Standardized mean differences (SMD), weighted mean differences (WMD), and 95% confidence intervals (95% CIs) were calculated using random/fixed effects models. Quality assessment was performed using the modified Jadad scale and the Cochrane Risk of Bias Tool. Sensitivity analysis and subgroup analysis were conducted based on drug dosage, treatment duration, and age of administration to further explore potential heterogeneity. Funnel plots were performed to assess publication bias and Begg's regression test was carried out for funnel plot asymmetry.

RESULTS

Twenty-two RCTs involving 1978 participants were included in the quantitative analysis. The mean quality of eligible studies was 4.2 out of 7 based on the modified Jadad scale. The results indicated that exercise training had a significant effect on reducing brachial-ankle pulse wave velocity [MD = - 0.69, 95%CI (- 1.11, - 0.27), P = 0.001], decreasing augmentation index (AIx) [MD = - 6.00, 95%CI (- 6.39, - 5.61), P < 0.00001] and AIx normalized to a heart rate of 75 beats per minute (AIx@75%) [MD = - 7.01, 95%CI - 7.91 to - 6.12, P < 0.00001], lowering systolic blood pressure [MD = - 6.19, 95%CI - 9.24 to - 3.15, P < 0.0001], diastolic blood pressure [MD = - 3.57, 95%CI (- 6.10, - 1.03), P = 0.006) and pulse pressure [MD = - 8.52, 95%CI (- 16.27, - 0.76), P = 0.03]. Subgroup analysis revealed that baseline blood pressure levels had a large impact on the effect of exercise training.

CONCLUSIONS

The systematic review and meta-analysis suggested that exercise training may ameliorate arterial stiffness and reduce blood pressure in postmenopausal women with elevated blood pressure. However, the optimal mode of exercise training that improves arterial stiffness and blood pressure in this population requires further investigation.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021211268.

Arterial Stiffness as a Cardiovascular Risk Factor for the Development of Preeclampsia and Pharmacopreventive Options

Arterial stiffness (AS) describes the rigidity of the arterial walls. Epidemiological studies have shown that increased AS is an independent predictive marker of cardiovascular (CV) morbidity and mortality in both pregnant and non-pregnant women. Preeclampsia (PE), a form of pregnancy-induced hypertension, affects approximately 5% of pregnancies worldwide. Preeclamptic women have a higher risk of CV disease (CVD), mainly because PE damages the heart's ability to relax between contractions. Different pharmacological approaches for the prevention of PE have been tested in clinical trials (e.g. aspirin, enoxaparin, metformin, pravastatin, and sildenafil citrate). In current clinical practice, only low-dose aspirin is used for PE pharmacoprevention. However, low-dose aspirin does not prevent term PE, which is the most common form of PE. Compromised vascular integrity precedes the onset of PE and therefore, AS assessment may constitute a promising predictive marker of PE. Several non-invasive techniques have been developed to assess AS. Compared with normotensive pregnancies, both carotid-femoral pulse wave velocity (cfPWV) and augmentation index (AIx) are increased in PE. In view of simplicity, reliability, and reproducibility, there is an interest in oscillometric AS measurements in pregnancies complicated by PE.

Increased Arterial Stiffness as a Predictor for Onset and Progression of Diabetic Retinopathy in Type 2 Diabetes Mellitus

INTRODUCTION

Brachial-ankle pulse wave velocity (baPWV), an indicator of arterial stiffness, has been demonstrated to be associated with type 2 diabetes mellitus (T2DM) and its vascular complications. This study was aimed at investigating the correlations of baPWV with both the presence and severity of diabetic retinopathy (DR) at baseline and at exploring the predictive role of baPWV in the new onset/progression of DR in the follow-up analysis.

METHODS

The prospective cohort study recruited 2,473 Chinese patients with T2DM, of whom 663 participants were finally included in the follow-up analysis. The presence and grading of DR were performed by the modified Early Treatment Diabetic Retinopathy Study. Uni- or multivariate linear and logistic regression models and Cox proportional-hazards regression analysis were conducted.

RESULTS

Of 2,473 patients with T2DM at baseline, 734 individuals were assessed to have DR and further categorized into 630 with non-sight-threatening DR (NSTDR) and 104 with STDR. In addition to the positive relationship between increased baPWV and the presence of DR, multinominal logistic regression analysis revealed that higher tertiles of baPWV were significantly related to the NSTDR (T2: OR = 1.62 (1.22, 2.15), p < 0.001, and T3: OR = 2.58 (1.86, 3.58), p < 0.001) and STDR group (T3: OR = 3.87 (1.87, 8.02), p < 0.001). During a follow-up (mean period of 16.4 months), 111 participants had new onset/progression of DR. The cox regressions showed that high baseline baPWV was correlated with increased risk of development/progression of DR (HR = 2.24, 95% CI (1.24, 4.03), p = 0.007, for T2 baPWV and HR = 2.90, 95% CI (1.49, 5.64), p = 0.002, for T3 baPWV) after adjustments for multiple factors.

CONCLUSIONS

Our results demonstrated that baseline baPWV might be an independent predictor in new onset/worsening of DR, suggesting that increased arterial stiffness might be involved in the development of DR. Follow-up studies with a longer duration are needed.

Increased cardio-ankle vascular index values in patients with acute branch retinal vein occlusion

Purpose:

Patients with retinal vein occlusions (RVOs) are at increased risk of cardiovascular disease. Arterial stiffness is an independent risk factor for cardiovascular events. Our aim is to evaluate the arterial stiffness in patients with acute branch retinal vein occlusion (BRVO) by using cardio-ankle vascular index (CAVI).

Methods:

This prospective study included 42 patients (18 male, mean age 57.5 ± 11.3) with acute BRVO and a matched control group (by age, sex, and presence of hypertension) with 70 (26 male, mean age 54.4 ± 9.4) patients. All patients and control subjects underwent complete ocular examination and CAVI measurement. BRVO was diagnosed based on clinical examination.

Results:

There were no significant differences between baseline clinical and demographic characteristics, echocardiographic measurements of left ventricular ejection fraction, systolic and diastolic blood pressure, and body mass index of the BRVO and control group. Both right and left CAVI values were found significantly higher in BRVO group (7.94 ± 1.53 vs 7.28 ± 1.25, P < 0.05 and 8.06 ± 1.41 vs 7.30 ± 1.26, P < 0.05, respectively). There were no significant difference in right and left ankle-brachial index values between the groups (1.05 ± 0.10 vs 1.06 ± 0.08, P = 0.46 and 1.04 ± 0.12 vs 1.05 ± 0.08, P = 0.46, respectively).

Conclusion:

Arterial stiffness is an important mediator of cardiovascular diseases. We found that CAVI which is a novel marker of the arterial stiffness is increased in patients with acute BRVO compared to controls.

Effect of metabolically healthy obesity on the development of arterial stiffness: a prospective cohort study

Background

Metabolically healthy obesity (MHO) has been reported to be associated with the development of vascular damage by the carotid intima-media thickness, but the relationship between metabolic health and obesity phenotypes and arterial stiffness is still unknown. Our hypothesized that different metabolic health and obesity phenotypes might be associated with the development of arterial stiffness, and that subjects in MHO phenotype might not have increased risks of arterial stiffness compared with those in metabolically healthy nonobesity phenotype (MHNO), while metabolic unhealthy individuals might have increased risks of arterial stiffness.

Methods

A prospective cohort of 2076 participants (aged 36-48 years) who were enrolled in the Hanzhong Adolescent Hypertension Cohort Study in 2017 was analyzed in a cross-sectional analysis. A subgroup of 202 participants from 2005 to 2017 was selected by an isometric sampling method and was included in the final longitudinal analysis.

Results

We identified four metabolic health and obesity phenotypes for both the cross-sectional and longitudinal analyses as follows: MHNO, metabolically unhealthy nonobesity (MUNO), MHO, and metabolically unhealthy obesity (MUO). In the cross-sectional analysis, individuals with the MHO phenotype had the lowest brachial-ankle pulse wave velocity (baPWV) levels of the four phenotypes (P < 0.001), and participants with the MHO phenotype had a similar risk of arterial stiffness after fully adjustment [odds ratio (OR) = 0.99 (0.61-1.60)] as the MUNO subjects. Subjects with metabolically unhealthy status had a significantly higher risk of arterial stiffness than the MHNO individuals, particularly females (P < 0.005). In the longitudinal analysis, subjects with the MUNO and MUO phenotypes had a significantly higher risk of arterial stiffness than the MHNO individuals after adjustment for age and sex [OR = 5.21 (2.26-12.02), OR = 3.32 (1.18-9.32), respectively].

Conclusions

The MHO phenotype did not significantly increase the progression of arterial stiffness. Metabolically unhealthy individuals (MUNO, MUO), regardless of obesity status, showed a worse effect for the development of arterial stiffness, particularly females.

Trial registration

NCT02734472. Registered 12 April 2016 - Retrospectively registered, http:www.clinicaltrials.gov.

High pulse wave velocity is associated with the severity of diabetic retinopathy in patients with type 2 diabetes

Pulse wave velocity (PWV) is a non-invasive test for assessing arterial stiffness, and brachial-ankle PWV has been used as an index of peripheral arterial stiffness. This study aimed to investigate the association between the PWV value and severity of diabetic retinopathy (DR). 846 patients with type 2 diabetes (T2DM) consecutively underwent brachial-ankle PWV, and the degree of PWV was defined by tertile. The severity of DR was categorized as no diabetic retinopathy (NDR), non-proliferative diabetic retinopathy (NPDR) or proliferative diabetic retinopathy (PDR) based on the Early Treatment Diabetic Retinopathy Study Scale. Multinomial logistic regression analyses were utilized not only to explore the association between the degree of PWV and severity of DR but also to examine the association of a high-tertile PWV with PDR. PWV levels, diabetes duration and blood pressure were all significantly higher in subjects with NPDR or PDR as compared with individuals with NDR. In the univariate analysis, the highest tertile of PWV (>19.6 m/s) was significantly associated with both NPDR (p<0.001) and PDR (p<0.001) as compared with NDR. After adjusting for confounding factors, the highest tertile of PWV remained significantly associated with PDR (p=0.005), but not with NPDR (p=0.107). Furthermore, the highest tertile of PWV was more significantly associated with PDR (OR=6.15, 95%CI 1.38 to 27.38) as compared with the lowest tertile. In our study, an increasing degree of PWV was positively associated with the severity of DR. High PWV was strongly associated with the risk of severe DR, especially PDR.

Endothelial dysfunction and impaired arterial wall properties in patients with retinal vein occlusion

Retinal vein occlusion (RVO) is a common retinal vascular lesion, and a leading cause of visual impairment. Patients with RVO have an increased risk for cardiovascular disease and share multiple common risk factors. In this study, we investigated the endothelial function and arterial stiffness of patients with RVO compared to healthy-control (CL) subjects. We enrolled 40 consecutive patients with RVO and 40 CL subjects. RVO was diagnosed by an ophthalmologist, endothelial function was evaluated by flow mediated dilation (FMD) in the brachial artery, and carotid-femoral pulse wave velocity (PWV) and augmentation index (AIx) of the radial artery were measured to evaluate arterial stiffness and reflected waves, respectively. No significant differences were detected between the studied groups in sex, age, presence of hypertension or dyslipidemia, body mass index, systolic and diastolic blood pressure levels, total cholesterol levels, and smoking habits (p > 0.05 for all). However, patients with RVO had impaired FMD (p = 0.002) and increased PWV (p = 0.004), even after adjustment for several confounders. Both FMD and PWV were also significantly and independently associated with the development of RVO. Furthermore, a significant and positive correlation between PWV and systolic blood pressure existed only in the CL group. Therefore, we have shown that RVO is associated with significant endothelial dysfunction and increased arterial stiffness. Our results strengthen the vascular theory, according to which, systemic endothelial dysfunction and arteriosclerosis play a significant role in the pathogenesis of RVO.

Firefighters' occupational stress and its correlations with cardiorespiratory fitness, arterial stiffness, heart rate variability, and sleep quality

This study investigated the correlations between firefighters' occupational stress and cardiorespiratory fitness, arterial stiffness, heart rate variability, and sleep quality. We examined 705 male firefighters aged 40-50 years in Seoul City, Korea from November 2016-December 2017. The Occupational stress scale was used to evaluate occupational stress; an exercise stress test was administered to measure participants' maximal oxygen uptake (VO2max); brachial-ankle pulse wave velocity was used to measure firefighters' arterial stiffness; their autonomic nervous system activities were analyzed to determine heart rate variability (HRR); and the Pittsburgh Sleep Quality Index was used to assess their sleep quality. We divided the sample population into tertile groups per their occupational stress scores; i.e., low-stress group (n = 233), medium-stress group (n = 237), and high-stress group (n = 235). They were compared per each indicator and correlations were examined. There was a significant difference in VO2max (p < .01), and arterial stiffness (p < .001) according to occupational stress levels. Occupational stress was significantly correlated with cardiorespiratory fitness (r = -.820, p < .05), arterial stiffness (r = .085, p < .05), and sleep quality (r = .276, p < .001), but not HRR. In conclusion, Firefighters' occupational stress is a key factor behind their elevated risk of cardiovascular diseases; therefore, we recommend programs aimed at reducing their occupational stress and preventing cardiovascular diseases.

Short-Term Effects of Beraprost Sodium on the Markers for Cardiovascular Risk Prediction in Type 2 Diabetic Patients with Microalbuminuria

BACKGROUND

To evaluate the changes in cardiovascular risk markers including pulse wave velocity (PWV), microalbuminuria, inflammatory cytokines, and adhesion molecules after treatment with beraprost sodium (BPS) in patients with diabetic nephropathy.

METHODS

This was a multicenter, prospective, randomized, double-blind, placebo-controlled trial. Type 2 diabetes mellitus patients with microalbuminuria were included. The primary endpoints were changes in microalbuminuria in spot urine and PWV after BPS or placebo (PCB) treatment for 24 weeks. The secondary endpoints were changes in clinical and metabolic parameters.

RESULTS

A total of 52 patients completed the 24-week trial. Changes in PWV were not different significantly in the BPS and PCB groups (right, P=0.16; left, P=0.11). Changes in microalbuminuria were 14.2±157.0 and 34.5±146.6 (μg/mg Cr) in the BPS and PCB groups, respectively (P=0.63). Subgroup analysis in the high blood pressure (BP) group (baseline systolic BP >120 mm Hg and diastolic BP >80 mm Hg), showed that microalbuminuria decreased by ?47.6 in the BPS group compared with an increase by 116.4 (μg/mg Cr) in the PCB group (P=0.04). Also, in the large waist circumference group (>95 cm), microalbuminuria decreased significantly in the BPS group (P=0.04).

CONCLUSION

Short-term treatment of BPS for patients with diabetic nephropathy did not show significant improvement in various cardiovascular risk factors. However, BPS significantly decreased microalbuminuria in study subjects with higher cardiovascular risk such as high BP or large waist circumference.

Albuminuria and masked uncontrolled hypertension in chronic kidney disease

Background

Masked uncontrolled hypertension (MUCH) is associated with greater target organ damage such as left ventricular hypertrophy, increased arterial stiffness and albuminuria. Whether MUCH independently associates with greater cardiovascular end-organ damage or kidney damage is unclear. The objective of this study was to assess the strength of the relationship of MUCH (awake ambulatory blood pressure ≥135/85 mmHg and clinic blood pressure <140/90 mmHg) with target organ damage.

Methods

In a cross-sectional study at a veterans' administration medical center, clinically normotensive veterans without chronic kidney disease (CKD) (n = 29) and 287 patients with CKD and controlled hypertension (CH, n = 193), MUCH (n = 67) and uncontrolled hypertension (UCH, n = 27) had evaluation of target organ damage. Target organ damage was measured by echocardiography [left ventricular mass index (LVMI)], arterial ultrasonography [aortic pulse wave velocity (PWV)] and 24-h urine collection [albuminuria (urine albumin to creatinine ratio)] in all participants.

Results

Compared to that of controls, LVMI was higher by 21.8 g/m2 (CI, 4.0-39.7 g/m2) in CH, 27.9 (CI, 8-47.8) in MUCH and 39.5 (CI, 15.7-63.2) in UCH (P < 0.01 for group differences, P < 0.01 for linear trend). Although differences persisted after adjustment for age, sex and race, they lost significance after adjustments for cardiovascular risk factors and their treatment. Compared to that of controls, PWV was different among CH, MUCH and UCH (P = 0.04 for group differences, P = 0.02 for linear trend). However, differences lost significance after adjustments for age, sex and race. Compared to that of controls, log2 UACR was higher by 2.40 mg/mg (CI, 1.28-3.52) in CH, 4.94 (CI, 3.70-6.18) in MUCH and 6.01 (CI, 4.49-7.53) in UCH (P < 0.0001 for group difference, P < 0.0001 for linear trend). Differences persisted after adjustment for age, sex and race, cardiovascular risk factors and their treatment and cardiovascular disease (P < 0.0001 for group difference, P < 0.0001 for linear trend).

Conclusions

MUCH is more strongly related to albuminuria compared with cardiovascular damage as assessed by left ventricular mass and PWV. A graded and an independent relationship of blood pressure classification status with albuminuria is consistent with the hypothesis that renal mechanisms may be more important than cardiovascular disease in mediating the pathogenesis of MUCH.

The association between elevated fasting plasma glucose levels and carotid intima-media thickness in non-diabetic adults: a population-based cross-sectional study

We assessed the association between the mean carotid intima-media thickness (CIMT) and fasting plasma glucose (FPG) levels in a low-income population in rural China. Adults aged ≥45 years without a history of diabetes, stroke, or cardiovascular disease were recruited. All participants were categorized into four groups according to FPG level. A total of 3509 participants were analyzed in this study. In the univariate analysis, sex, age, education level, hypertension, central obesity, current smoking, alcohol consumption, and higher levels of FPG, total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were associated with mean CIMT and frequency of increased CIMT. FPG levels were significantly associated with mean CIMT; each 1-mmol/L increase in FPG resulted in a 2.75-μm increase in mean CIMT when adjusted by age, sex, education level, current smoking status, alcohol consumption, hypertension, and the levels of TC, TG, HDL-C, and LDL-C (P = 0.044). However, the association between FPG and the frequency of increased CIMT disappeared after adjusting by covariates. These findings indicate that FPG is an independent determinant of mean CIMT in a non-diabetic population. Management and control of FPG levels is crucial for preventing atherosclerosis in populations with high stroke risks in China.

Arterial stiffness and its relationship to clinic and ambulatory blood pressure: a longitudinal study in non-dialysis chronic kidney disease

Background

Both arterial stiffness and systolic blood pressure (BP) are established cardiovascular risk factors, yet little is known about their interrelationship in chronic kidney disease (CKD). The goal of this prospective study was to describe the trajectory of aortic pulse wave velocity (PWV) and BP and to compare the longitudinal interrelationship of BP (clinic and 24 h ambulatory recording) with the PWV.

Methods

Clinic BP was taken in two ways: at the time of the measurement of the PWV (Clinic-S) and as an average of triplicate measurements on three separate occasions within 1 week (Clinic-M). 24 h ambulatory BP was measured using a validated monitor and PWV was measured in the aorta using an echo-Doppler technique.

Results

Among 255 veterans with CKD followed for over up to 4 years, the rate of change of log PWV was inversely related to the baseline PWV; the trajectories were variable among individuals and the net population change was no different from zero. In contrast, systolic BP significantly increased, but linearly, and a strong relationship was seen between cross-sectional and longitudinal changes in Clinic-M systolic BP and log PWV. In contrast, a longitudinal relationship between Clinic-S and log PWV was absent. In the case of 24-h ambulatory BP, a strong cross-sectional change was seen between awake and 24 h systolic BP but not between sleep BP and log PWV.

Conclusion

In conclusion, among people with CKD, the PWV changes over time and is inversely related to the baseline PWV. An average of clinic BP measurements taken over three visits, but not single measurements, are useful to assess the PWV and its change over time. Differences exist between ambulatory BP monitoring recording during the sleep and awake states in their ability to predict the PWV. Taken together, these data support the view that among those with CKD not on dialysis, targeting clinic BP taken on multiple occasions using a standardized methodology or daytime ambulatory systolic BP may slow the progression of arterial damage.

Microvascular endothelial function in Japanese early adolescents

Endothelial dysfunction is the early predictive factor for the development of atherosclerosis and future cardiovascular diseases in adulthood. The prevalence of endothelial dysfunction in children and early adolescents is increasing worldwide. Peripheral arterial tonometry is a noninvasive technique for assessing peripheral microvascular function and is used as a validated marker of endothelial function. We assessed anthropometric parameters, blood pressure, arterial stiffness, and peripheral endothelial function in 157 Japanese early adolescents (75 boys and 82 girls). We measured peripheral endothelial function by using peripheral arterial tonometry to determine the reactive hyperemia index, and assessed the association of reactive hyperemia index with parameters of anthropometry and arterial stiffness. The mean reactive hyperemia index of all subjects was 1.85 ± 0.6, and there was no difference of reactive hyperemia index according to sex. Reactive hyperemia index was significantly associated with systolic and diastolic blood pressures, and had no correlation with anthropometric parameters and arterial stiffness markers. The reactive hyperemia index values among Japanese early adolescents were similar to those reported in previous studies on children and early adolescents. This noninvasive technique may be useful for the assessment of microvascular endothelial function among children and early adolescents.

Brachial-Ankle Pulse Wave Velocity as a Predictor of Silent Cerebral Embolism after Carotid Artery Stenting

BACKGROUND

In neuroendovascular therapy, the effect of arterial stiffness on postprocedural cerebral thromboembolism is unknown. In this observational study, we examined the relationship between cerebral thromboembolism after carotid artery stenting and arterial stiffness.

METHODS

From April 2015 to February 2017, we enrolled consecutive patients undergoing scheduled carotid artery stenting in our institution. In all patients, preprocedural brachial-ankle pulse wave velocity was used to assess arterial stiffness, whereas the number of new cerebral ischemic lesions on diffusion-weighted magnetic resonance imaging was assessed after treatment. We also analyzed patient data and details of procedures in patients with carotid artery stenting.

RESULTS

Twenty-one patients completed the study. The mean brachial-ankle pulse wave velocity was 1879 cm/s. There was no association of cerebral thromboembolisms with age, unstable plaque, protection device, or type of stent. However, the brachial-ankle pulse wave velocity was an independent predictor of cerebral thromboembolisms (P = .0017).

CONCLUSIONS

Brachial-ankle pulse wave velocity is predictive of silent cerebral embolisms on diffusion-weighted magnetic resonance imaging after carotid artery stenting.

Brachial-ankle pulse wave velocity and metabolic syndrome in general population: the APAC study

Background

Metabolic syndrome (MetS) is correlated with arterial stiffness and can be evaluated by brachial-ankle pulse wave velocity (baPWV). We investigated potential associations between MetS and baPWV in a Chinese community population.

Methods

The community-based Asymptomatic Polyvascular Abnormalities in Community study examined asymptomatic polyvascular abnormalities in a Chinese population aged ≥40 years. The relationship between MetS and its components and baPWV was analyzed by multivariate logistic and linear regression models.

Results

Out of 5181 study participants, 1271 subjects (24.53%) had MetS. Mean values of baPWV in subjects with 0, 1, 2,3, 4, and 5 components of MetS were 1430, 1526, 1647, 1676,1740, and 1860 cm/s, respectively (p < 0.001 for trend). After adjusting for confounding risk factors, MetS was significantly associated with baPWV (odds ratio [OR]: 2.74; 95% CI: 2.28, 3.30). Among the five components of MetS, elevated blood pressure was the most important factor for baPWV. All models of multivariate linear regression analysis showed a significant positive correlation between the increasing numbers of MetS components and baPWV (p < 0.0001).

Conclusions

baPWV was associated with MetS and was greater with increasing numbers of MetS components. Elevated blood pressure was the most important factor for baPWV.

Retinopathy is a Strong Determinant of Atherosclerosis in Type 2 Diabetes: Correlation with Carotid Intima Media Thickness

OBJECTIVE

We investigated the correlation between the severity of diabetic retinopathy (DR) and carotid intima media thickness (IMT) as a marker of atherosclerosis in patients with type 2 diabetes.

METHODS

The study group consisted of 140 normotensive Egyptian patients (68 males and 72 females) with type 2 diabetes and DR. Carotid IMT was evaluated using high-resolution B-mode ultrasonography. DR was assessed and graded using colored fundus photography and fundus fluorescein angiography, as either nonproliferative DR (NPDR) or proliferative DR (PDR).

RESULTS

Carotid IMT was greater in patients with PDR compared to those with NPDR (1.094 ± 0.142 mm vs. 0.842 ± 0.134 mm; P<.001). Carotid IMT showed positive correlation with diabetes duration (P<.01), systolic blood pressure (P<.001), diastolic blood pressure (P<.01), fasting blood glucose (P<.01), postprandial blood glucose (PPBG) (P<.001), glycated hemoglobin (P<.01), total cholesterol (P<.01), triglycerides (TGs) (P<.001), and DR (P<.0001). No significant difference was found between males and females in any of the studied parameters. Multiple regression analysis revealed that the determinants of carotid IMT in the studied group were age (P<.01), PPBG (P<.01), TGs (P<.001), and DR (P<.0001).

CONCLUSION

Our study proves that both NPDR and PDR are strong determinants of carotid IMT and atherosclerosis in patients with type 2 diabetes.

Protective effects of (6R)-5,6,7,8-tetrahydro-l-biopterin on local ischemia/reperfusion-induced suppression of reactive hyperemia in rat gingiva

We herein investigated the regulatory mechanism in the circulation responsible for rat gingival reactive hyperemia (RH) associated with ischemia/reperfusion (I/R). RH was analyzed using a laser Doppler flowmeter. RH and I/R were elicited by gingival compression and release with a laser Doppler probe. RH increased in a time-dependent manner when the duration of compression was between 30 s and 20 min. This increase was significantly suppressed by N^ω-nitro-l-arginine-methyl-ester (l-NAME), 7-nitroindazole (7-NI), and 2,4-diamino-6-hydroxypyrimidine (DAHP). However, RH was markedly inhibited following 60 min of compression. This inhibition was significantly decreased by treatments with superoxide dismutase (SOD), (6R)-5,6,7,8-tetrahydro-l-biopterin (BH₄), and sepiapterin. The luminescent intensity of superoxide anion (O₂^•−)-induced 2-methyl-6-(4-methoxyphenyl)-3,7-dihydroimidazo-[1,2-a] pyrazine-3-one (MCLA) was markedly decreased by SOD and BH₄, but only slightly by sepiapterin. BH₄ significantly decreased O₂^•− scavenging activity in a time-dependent manner. These results suggested that nitric oxide (NO) secreted by the nitrergic nerve played a role in regulating local circulation in rat gingiva. This NO-related regulation of local circulation was temporarily inhibited in the gingiva by the I/R treatment. The decrease observed in the production of NO, which was caused by suppression of NO synthase (NOS) activity subsequent to depletion of the NOS co-factor BH₄ by O₂^•−, played a partial role in this inhibition.

Relative Importance of Aortic Stiffness and Volume as Predictors of Treatment-Induced Improvement in Left Ventricular Mass Index in Dialysis

This study aimed to explore the relative contribution of aortic stiffness and volume in treatment-induced change of left ventricular mass in dialysis. Hypertension in Hemodialysis Patients Treated with Atenolol or Lisinopril trial compared the effect of lisinopril versus atenolol in reducing left ventricular mass index; 179 patients with echo measurements of aortic pulse wave velocity and left ventricular mass at baseline were included. In unadjusted analysis, overall reductions of 26.24 g/m² (95% CI: -49.20, -3.29) and 35.67 g/m² (95% CI: -63.70, -7.64) in left ventricular mass index were noted from baseline to 6 and 12 months respectively. Volume control emerged as an important determinant of regression of left ventricular mass index due to the following reasons: (i) additional control for change in ambulatory systolic blood pressure mitigated the reduction in left ventricular mass index in the statistical model above [6-month visit: -18.6 g/m² (95% CI: -43.7, 6.5); 12-month visit: -22.1 g/m² (95% CI: -52.2, 8.0)] (ii) regression of left ventricular hypertrophy was primarily due to reduction in left ventricular chamber and not wall thickness and (iii) adjustment for inferior vena cava diameter (as a proxy for volume) removed the effect of time on left ventricular mass index reduction [6-month visit: -6.6 g/m² (95% CI: (-41.6, 28.4); 12-month visit: 0.6 g/m² (95% CI: -39.5, 40.7)]. In contrast, aortic pulse wave velocity was neither a determinant of baseline left ventricular mass index nor predictor of its reduction. Among dialysis patients, ambulatory systolic pressure, a proxy for volume expansion, but not aortic stiffness is more important predictor of reduction in left ventricular mass index. Improving blood pressure control via adequate volume management appears as an effective strategy to improve left ventricular hypertrophy in dialysis.

Using brachial-ankle pulse wave velocity to screen for metabolic syndrome in community populations

The aim of this study is to investigate the viability of using brachial-ankle pulse wave velocity (baPWV) as a primary tool to screen metabolic syndrome (MetS), and to explore the risk factors of MetS in community populations. A total of 1914 subjects completed medical examination in Shanghai. BaPWV was significantly associated with the components of MetS. The area under curve (AUC) and its 95% confidence interval (CI) in total group were 62.50% and 60.00%-65.30% with the appropriate cut-off point being 1435 cm/sec. The AUC (95%CI) of three subgroups (40-50 yrs, 50-60 yrs and over 60 yrs group) were 75.30% (67.48%-83.35%), 63.35% (58.96%-67.60%), 55.37% (51.19%-60.01%), respectively. A clear pattern surfaced in the process of investigation: the younger were the subjects group, the better receiver operating characteristic (ROC) efficacy would emerge; and the higher sensitivity was, the better negative predictive value (NPV) would be. Male gender, high baPWV values, elevated uric acid (UA) and excess hypersensitive C reaction protein (hs-CRP) levels were stayed in the two regression models as the independent risk factors for MetS. We conclude that baPWV may serve as a potential screening tool for MetS at the cut-off point of 1435 cm/sec.

Effect of lisinopril and atenolol on aortic stiffness in patients on hemodialysis

BACKGROUND AND OBJECTIVES

Whether improvements in arterial compliance with BP lowering are because of BP reduction alone or if pleiotropic effects of antihypertensive agents contribute remains unclear. It was hypothesized that, among patients on hemodialysis, compared with a β-blocker (atenolol), a lisinopril-based therapy will better reduce arterial stiffness.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Among 200 participants of the Hypertension in Hemodialysis Patients Treated with Atenolol or Lisinopril Trial, 179 patients with valid assessment of aortic pulse wave velocity at baseline (89 patients randomly assigned to open-label lisinopril and 90 patients randomly assigned to atenolol three times a week after dialysis) were included in the secondary analysis. Among them, 109 patients had a valid pulse wave velocity measurement at 6 months. Monthly measured home BP was targeted to <140/90 mmHg by addition of antihypertensive drugs and dry weight adjustment. The difference between drugs in percentage change of aortic pulse wave velocity from baseline to 6 months was analyzed.

RESULTS

Contrary to the hypothesis, atenolol-based treatment induced greater reduction in aortic pulse wave velocity relative to lisinopril (between drug difference, 14.8%; 95% confidence interval, 1.5% to 28.5%; P=0.03). Reduction in 44-hour ambulatory systolic and diastolic BP was no different between groups (median [25th, 75th percentile]; atenolol: -21.5 [-37.7, -7.6] versus lisinopril: -15.8 [-28.8, -1.5] mmHg; P=0.27 for systolic BP; -14.1 [-22.6, -5.3] versus -10.9 [-18.4, -0.9] mmHg, respectively; P=0.30 for diastolic BP). Between-drug difference in change of aortic pulse wave velocity persisted after adjustments for age, sex, race, other cardiovascular risk factors, and baseline ambulatory systolic BP but disappeared after adjustment for change in ambulatory systolic BP (11.8%; 95% confidence interval, -2.3% to 25.9%; P=0.10).

CONCLUSIONS

Among patients on dialysis, atenolol was superior in improving arterial stiffness. However, differences between atenolol and lisinopril in improving aortic stiffness among patients on hemodialysis may be explained by BP-lowering effects of drugs.

Brachial artery reactivity and vascular reactive hyperemia for preoperative anaesthesia risk assessment - an observational study

Background

Non-invasive measures of vascular reactivity have emerged to refine cardiovascular risk. However, limited data exists investigating vascular reactivity as a preoperative diagnostic tool for anesthesiologists. In this study, we compare the utility of two non-invasive techniques, Brachial Artery Reactivity Testing (BART) and Digital Thermal Monitoring (DTM), as surrogates for measuring vascular reactivity.

Methods

Following IRB approval, 26 patients scheduled for major thoracic surgery (e.g. esophagectomy and pneumonectomy) were studied prospectively. BART [Flow mediated dilation (FMD) and Peak flow velocity (PFV)] and DTM [Temperature rebound (TR%)] were performed preoperatively at baseline using 5 minute blood pressure cuff occlusion of the upper arm. Statistical summaries were provided for the comparison of BART and DTM with select patient characteristics, and correlations were used to investigate the strength of the relationship between BART and DTM measurements.

Results

Patients preoperatively diagnosed with hyperlipidemia were associated with lower FMD% values {Median (Range): 14.8 (2.3, 38.1) vs. 6.2 (0.0, 14.3); p = 0.006}. There were no significant associations between BART and DTM techniques in relation to cardiovascular risk factors or postoperative complications.

Conclusion

Our study suggests that impaired vascular reactivity as measured by BART is associated with the incidence of hyperlipidemia. Also, using a novel technique such as DTM may provide a simpler and more accessible point of care testing for vascular reactivity in a perioperative setting. Both non-invasive techniques assessing vascular function warrant further refinement to better assist preoperative optimization strategies aimed at improving perioperative vascular function.

High-Sensitivity C-Reactive Protein in Japanese Patients with Type 2 Diabetes

OBJECTIVE

To assess the relationship between high-sensitivity (HS) C-reactive protein (CRP) and metabolic syndrome (MetS) or atherosclerosis and to assess effects of strict metabolic control on the degree of inflammation and MetS in patients with type 2 diabetes.

RESEARCH METHODS AND PROCEDURES

Four hundred thirteen patients with diabetes were enrolled in the cross-sectional study. Of these 413 patients, 161 patients were further admitted for 2.4 +/- 0.4 weeks (mean +/- SD) to investigate the change in HS-CRP or other parameters under strict metabolic control.

RESULTS

Log-transformed HS-CRP value (log HS-CRP) was strongly correlated with BMI (r = 0.448, p < 0.01). Log HS-CRP was also correlated with the presence of MetS or each component of MetS. Furthermore, a positive significant trend in HS-CRP levels was shown with an increasing number of MetS components (p < 0.05). Log HS-CRP showed a significant positive correlation with carotid artery intima-media thickness (IMT) (r = 0.152, p < 0.01). In multiple step-wise regression analysis, BMI, hemoglobin A(1c), right IMT, duration of diabetes, and triglyceride were selected as explanatory variables for log HS-CRP (R2 = 0.412). Under strict metabolic control, HS-CRP was significantly (p < 0.01) lower, together with lower levels of other markers for MetS. The change in HS-CRP was significantly correlated with the change in BMI (r = 0.161, p = 0.04).

DISCUSSION

In subjects with type 2 diabetes, HS-CRP levels are related to MetS and subclinical atherosclerosis. Strict weight management and metabolic control were associated with a reduction in HS-CRP levels, and changes in HS-CRP were related to changes in weight, supporting the hypothesis that lifestyle modification reduces inflammation and the risk of CHD.

The association between preeclampsia and arterial stiffness

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

Association between apolipoprotein E polymorphism and subclinic atherosclerosis in patients with type 1 diabetes mellitus

OBJECTIVE

The most important cause of morbidity and mortality in type 1 diabetes mellitus (DM) is atherosclerosis. Apolipoprotein E (Apo E) polymorphism is accused of being the genetic risk factor for atherosclerosis. The aim of the present study was to determine which Apo E polymorphism was related to atherosclerosis in patients with type 1 DM.

METHODS

Seventy-four patients with type 1 DM were enrolled in the study. Age, diabetes duration, daily insulin dose, microalbuminuria, and major cardiovascular risk factors including anthropometric and metabolic parameters were assessed in each patient. Non-invasive ultrasonographic measurements were also performed. For determination of Apo E genotype, DNA was extracted from venous blood from all subjects using standard methods. Apo E genotyping was performed using a PCR-restriction fragment-length polymorphism assay.

RESULTS

Systolic blood pressure and carotid artery intima-media thickness (CA-IMT) were increased in subjects with E4/E4 polymorphism. According to univariate analysis, when adjusted for all risk factors, genotypes did not differ for total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and triglycerides (p>0.05). However, E3/E3, E3/E4 and E4/E4 genotypes were found to be associated with an increase in CA-IMT (p<0.001).

CONCLUSIONS

Our results suggest that the polymorphism associated with atherosclerosis in type1 DM is Apo E4/E4.

Early Changes in Vascular Dynamics in Relation to Twin-Twin Transfusion Syndrome

Aclearer understanding of the early determinants of normal and abnormal vascular development is pivotal in order to identify those at increased risk of later vascular disease, and perhaps to prevent it by early intervention. Measurement of pulse wave velocity(PWV) has been used in the postnatal evaluation of the monochorionic(MC) twins. They are genetically identical and those with twin-twin transfusion syndrome(TTTS) provide an ideal natural model in whom to study the influence of differing haemodynamic stresses on the developing vascular tree. We investigated firstly whether surviving twin pairs with TTTS have altered arterial distensibility in childhood by comparing PWV in the radial arteries of surviving MC twin pairs with TTTS and in two control groups, one cohort of MC twins without TTTS and another dichorionic group (DC) Secondly, we tested a cohort of TTTS twin pair survivors treated with laser photocoagulation. The co-twin pairs in the group managed palliatively with amnioreduction showed increased PWV in the donor and reduced PWV in the recipient twins. This was neither seen in the laser-treated, nor in the control groups. Our studies suggest that a period of haemodynamic imbalance gives rise to changes in a muscular conduit artery that persist at least into infancy and it seems that by correcting the abnormal haemodynamics relatively soon after the disease process had begun, the alterations in elasticity are prevented. These studies are the first to demonstrate fetal programming of the vascular bed in humans, and prevention or reversal of this programming by an intervention in mid-gestation.

The role of inflammation on atherosclerosis, intermediate and clinical cardiovascular endpoints in type 2 diabetes mellitus

BACKGROUND

Type 2 diabetes mellitus (T2DM) is associated with increased cardiovascular morbidity and mortality. Sub-clinical systemic inflammation is often present in T2DM patients. Systemic inflammation has also been implicated in the pathophysiology of atherosclerosis. This review investigates the direct evidence present in literature for the effect of inflammation on atherosclerosis, specifically in the setting of T2DM. Special emphasis is given to the pathogenesis of atherosclerosis as well as intermediate and clinical cardiovascular endpoints. The important role of deteriorated endothelial function in T2DM was excluded from the analysis.

METHODS

Extensive literature searches were performed using the PubMed and Web of Science databases. Articles were identified, retrieved and accepted or excluded based on predefined criteria.

RESULTS

Substantial evidence was found for an important inflammatory component in the pathogenesis of atherosclerosis in T2DM, demonstrated by inflammatory changes in plaque characteristics and macrophage infiltration. Most epidemiologic studies found a correlation between inflammation markers and intermediate cardiovascular endpoints, especially intima-media thickness. Several, but not all clinical trials in T2DM found that reducing sub-clinical inflammation had a beneficial effect on intermediate endpoints. When regarding cardiovascular events however, current literature consistently indicates a strong relationship between inflammation and clinical endpoints in subjects with T2DM.

CONCLUSION

Current literature provides direct evidence for a contribution of inflammatory responses to the pathogenesis of atherosclerosis in T2DM. The most consistent relation was observed between inflammation and clinical endpoints.

Resistance Training Effects on Arterial Compliance in Premenopausal Women

Endurance training has been shown to increase arterial compliance; however, the effect of resistance training is unclear. Purpose: The purpose of this study was to examine the effect lower body resistance training on arterial compliance in healthy premenopausal women. Methods: Thirty-two women were assigned to a resistance training group (n = 21) or a control group (n = 11). Large (C1) and small (C2) arterial compliance (Pulse Contour Analysis) were measured at baseline and after twelve weeks of training. Results: Two-way (group × time) repeated measured ANOVA did not detect significant group, time effects or group × time interactions for small arterial compliance (P > 0.05). There was a significant time effect for large arterial compliance (P < 0.05), which increased in both groups. Conclusions: In contrast to previous studies in men, which found decrease in arterial compliance with resistance training, no decrease in arterial compliance was observed.

Aortic pulse wave velocity predicts cardiovascular mortality in middle-aged and elderly Japanese men

BACKGROUND

Aortic pulse wave velocity (PWV) is widely used as a noninvasive index of arterial stiffness and was used in the present study to investigate the relationship between PWV and cardiovascular mortality in the middle-aged and elderly Japanese population using a longitudinal study design.

METHODS AND RESULTS

From 1988 to 2003, a total of 3,960 men (50-69 years old at baseline) who underwent medical check-ups and measurement of PWV, which was standardized for diastolic blood pressure, were recruited and divided into 4 groups according to the PWV values. The average follow-up period was 8.2 years. Mortality from all-causes and from cardiovascular disease significantly increased as PWV increased in the entire follow-up period. Multivariate-adjusted relative risks of all-cause and cardiovascular disease mortality for the highest quartile of PWV (>9.0 m/s) were 1.28 (95% confidence interval (CI) 0.97-1.68) and 1.83 (95%CI 1.02-3.29), respectively, compared with the lowest quartile (<7.5 m/s).

CONCLUSIONS

An increased PWV can predict cardiovascular mortality in middle-aged and elderly Japanese men.

Arterial stiffness and interdialytic weight gain influence ambulatory blood pressure patterns in hemodialysis patients

Besides an overall increase in blood pressure, hemodialysis patients have marked disturbance in interdialytic ambulatory blood pressure pattern that is characterized by blunted circadian amplitude and a steady rise in blood pressure between dialysis treatments. The pathophysiology of this abnormal blood pressure profile is poorly understood. We hypothesized that the circadian amplitude, the interdialytic increase (linear trend), and the average level of blood pressure (the intercept) are related to the extent of arterial stiffening and the degree of accumulation of salt and water between dialysis treatments. Using a generalized cosinor model, we simultaneously compared the impact of interdialytic weight gain and echo-Doppler-measured aortic pulse wave velocity on the mean level of blood pressure, linear changes over the interdialytic interval, and oscillatory changes in blood pressure. In a cross-sectional analysis of 11,833 blood pressure measurements from 125 long-term hemodialysis patients, we found that aortic pulse wave velocity and interdialytic weight gain had a substantial impact on interdialytic ambulatory blood pressure level, trends, and rhythms. Arterial stiffness was associated with an overall increase in the level (intercept) of systolic, diastolic, and pulse pressure. Interdialytic weight gain, on the other hand, was associated with interdialytic increase (linear trend) in blood pressure. The circadian amplitude was blunted by increments in either arterial stiffness or interdialytic weight gain. Since patterns of ambulatory arterial blood pressure are related to cardiovascular risk factors such as interdialytic weight gain and increased arterial stiffness, the pattern of ambulatory blood pressure recordings may also be of prognostic significance in hemodialysis patients.

Beneficial effect of beraprost sodium plus telmisartan in the prevention of arterial stiffness development in elderly patients with hypertension and cerebral infarction

Beraprost sodium (BPS, an analogue of prostacyclin) and telmisartan (TS, an angiotensin receptor blocker) have been reported to have a preventive effect on arterial stiffness in patients with cardiovascular diseases. The purpose of this study was to estimate the effects of a combined therapy using BPS and TS on arterial pulse wave velocity (PWV) values in elderly patients with hypertension and cerebral infarction. Over a 3-month period, 80 subjects with hypertension and histories of cerebral infarction received BPS only (120 microg/day p.o.), TS only (40 mg/day p.o.), both BPS and TS, or no medication at all (control). Arterial PWV and ankle brachial indices (ABI) were determined prior to and after 3 months of drug administration. During the follow-up, there were no significant changes in any of the parameters monitored with the exception of a significant decrease in systolic blood pressure in the BPS only, TS only, and BPS plus TS groups when compared to controls. The difference values for PWV in the control group, BPS only group, TS only group, and BPS plus TS group were +232.5, -114.6, -151.5, and -248.1 cm/s, respectively. The reduction values were significantly more pronounced in the BPS plus TS group than in the BPS only (P=0.037) and the TS only (P=0.022) groups. When BPS is combined with TS, an overall additive effect is seen in the improvement of PWV in Japanese patients with hypertension and cerebral infarction. This combination therapy is more beneficial than the corresponding monotherapies.

Noninvasive assessment of preclinical atherosclerosis

Initially considered as a semipermeable barrier separating lumen from vessel wall, the endothelium is now recognised as a complex endocrine organ responsible for a variety of physiological processes vital for vascular homeostasis. These include the regulation of vascular tone, luminal diameter, and blood flow; hemostasis and thrombolysis; platelet and leucocyte vessel-wall interactions; the regulation of vascular permeability; and tissue growth and remodelling. The endothelium modulates arterial stiffness, which precedes overt atherosclerosis and is an independent predictor of cardiovascular events. Unsurprisingly, dysfunction of the endothelium may be considered as an early and potentially reversible step in the process of atherogenesis and numerous methods have been developed to assess endothelial status and large artery stiffness. Methodology includes flow-mediated dilatation of the brachial artery, assessment of coronary flow reserve, carotid intimamedia thickness, pulse wave analysis, pulse wave velocity, and plethysmography. This review outlines the various modalities, indications, and limitations of available methods to assess arterial dysfunction and vascular risk.

Effects of alendronate sodium therapy on carotid intima media thickness in postmenopausal women with osteoporosis

Osteoporosis and cardiovascular disease are major health problems that lead to morbidity and mortality. Bisphosphonates are among the drugs used most frequently worldwide to treat osteoporosis, especially in older women. B-mode ultrasonography has recently become a valuable tool for early diagnosis of atherosclerotic disease because of its ability to measure carotid artery intima media thickness (CIMT). The purpose of the present study was to investigate whether alendronate sodium therapy has an effect on CIMT in postmenopausal women with osteoporosis. A total of 71 postmenopausal women with osteoporosis were evaluated before and after they began taking alendronate sodium; follow-up was provided for an average of 13+/-2 mo. Osteoporosis was diagnosed with the use of dual-energy x-ray absorptiometry, and therapy with alendronate sodium was begun at a dose of 70 mg/wk. For CIMT, B-mode ultrasonography was performed on the right and left middle and distal main carotid arteries. Before alendronate sodium therapy was initiated, the average CIMT value was 0.734+/-0.121 mm; after therapy, the average CIMT was 0.712+/-0.111 mm. This difference was not confirmed to be statistically significant. Treatment of osteoporosis does not seem to have an effect on CIMT, which is an early marker of atherosclerosis.

Monitoring Carotid Blood Flow and ECG for Cardiovascular Disease in Elder Subjects

This report is to investigate the correlation between common carotid blood flow (CCBF) properties and the risk factors for cardiovascular disease. The measurement system was designed for simultaneously monitoring of CCBF and electrocardiogram (ECG) in order to get more valid information for detection and diagnosis of cardiovascular disease. In our study, blood flow velocimeter was developed to measure blood flow in carotid by using ultrasound Doppler technique. This measurement system is based on a continuous-wave (CW) Doppler ultrasound method with two semicircular piezoelectric (PZT) transducers, one continuously transmitting ultrasound, and the other continuously receiving the echoes. Eleven patients with cardiovascular disease underwent in the experiment. In the report, blood flow was compared with data from 25 healthy subjects which asymptomatic subjects putatively free of cardiovascular disease as controls. The maximum of CCBF velocity was 102.8 (SD 18.3) cm/s in the 25 healthy subjects. While, the maximum of CCBF velocities were 53.9 (SD 16.6) cm/s in the eleven cardiac patients. The data suggest that CCBF velocity decreased significantly in the cardiac patients and by simultaneously monitoring of CCBF and ECG were probably obtained more valid information to detect and diagnose cardiovascular disease at the early stage.

A novel method for evaluating human carotid artery elasticity: possible detection of early stage atherosclerosis in subjects with type 2 diabetes

We recently developed a novel method for evaluating the elasticity of arterial walls, the phased tracking method. Herein, we evaluated atherosclerosis of the carotid artery with this method in 242 individuals with type 2 diabetes. In multiple regression analysis of subject status, age, systolic blood pressure and hyperlipidemia were found to be independently associated with carotid artery elasticity values. We also measured currently established values for atherosclerosis, carotid artery IMT and baPWV, in these subjects. Carotid artery elasticity correlated with max IMT (r=0.291, p<0.01), plaque score (PS) (r=0.220, p<0.01) and baPWV (r=0.345, p<0.01). Elasticity, max IMT and plaque score, all correlated with the number of risk factors for atherosclerosis, i.e. hypertension, hyperlipidemia and smoking, in addition to diabetes, consistent with the view that these values reflect atherosclerosis. Importantly, however, in subjects with IMT <1.1mm, who are classified as not having atherosclerosis as defined by IMT criteria, only carotid artery elasticity correlated with the number of risk factors (p<0.05). These results suggest that (1) the measured carotid artery elasticity values reflect atherosclerosis and (2) our novel method has potential for detecting atherosclerosis in its early stage.

Different effects of oral conjugated estrogen and transdermal estradiol on arterial stiffness and vascular inflammatory markers in postmenopausal women

AIMS

We compared the effects of oral conjugated equine estrogen (CEE) therapy and transdermal estradiol therapy on pulse wave velocity (PWV) and circulating levels of vascular inflammatory markers in postmenopausal women and we also explored the interrelationship between the change in PWV and the changes in vascular inflammatory markers.

METHODS AND RESULTS

In a randomized 12-month trial, 28 postmenopausal women received a continuous oral CEE plus cyclic medroxyprogesterone acetate (MPA), 28 received a continuous transdermal estradiol patch plus cyclic MPA, and 27 did not receive either therapy. In each subject, we measured the brachial-ankle PWV (baPWV) using an automated device, the blood pressure, and the circulating levels of vascular inflammatory markers (C-reactive protein [CRP], cell adhesion molecules [CAMs], monocyte chemoattractant protein-1 [MCP-1], and matrix metalloproteinase [MMP-9]) before and 12 months after the start of the study. Oral CEE therapy did not change the baPWV but significantly increased the CRP and MMP-9 levels (P<0.05, each) and significantly decreased the CAMs and MCP-1 levels (P<0.05, each). Transdermal estradiol therapy significantly decreased the baPWV, and the CAMs and MCP-1 levels (P<0.05, each) but had no effect on the CRP or MMP-9 levels. No significant changes were seen in the control group. The blood pressures of the subjects remained unchanged. In the transdermal estradiol group, the change in baPWV was not significantly correlated with the changes in vascular inflammatory markers.

CONCLUSION

Transdermal estradiol, but not oral CEE therapy, may have antiatherosclerotic effects by improving arterial stiffness. The reduction in baPWV may contribute to the direct effect of estrogen, but not to the decrease in estrogen-induced vascular inflammatory markers.

Effects of estradiol alone and combined with norethisterone acetate on pulse-wave velocity in hypertensive postmenopausal women

BACKGROUND

Arterial hypertension and postmenopausal reduction of estrogen levels may be involved in modifications of the stiffness of large arteries.

OBJECTIVES

To evaluate the pulse-wave velocity (PWV) and indirectly the arterial stiffness in hypertensive postmenopausal women submitted to hormone therapy with estradiol alone or combined with norethisterone acetate.

SUBJECTS

Forty-five hypertensive postmenopausal women were double-blindly, randomly assigned to three arms of treatment: placebo (group I); estradiol 2 mg/day (group II); or estradiol 2 mg/day and norethisterone acetate 1 mg/day (group III).

METHODS

Arterial stiffness was assessed from PWV measurements of the common carotid and femoral arteries (CF-PWV) and the common carotid and radial arteries (CR-PWV) obtained using the automatic Complior(R) device, taken at baseline and after 12 weeks of treatment.

RESULTS

After the 12-week treatment, values of CF-PWV and CR-PWV were not significantly different (p = 0.910 and p = 0.736, respectively) among the groups. Systolic blood pressure showed a positive correlation with CF-PWV in groups II and III (p = 0.02 and p < 0.001, respectively).

CONCLUSIONS

PWV and arterial stiffness in postmenopausal hypertensive women did not reduce over a 12-week treatment with estradiol alone compared with the same period of treatment with estradiol combined with norethisterone acetate.

Elevated arterial stiffness in postmenopausal women with osteoporosis

OBJECTIVES

Osteoporosis and increased pulse wave velocity (PWV) are cardiovascular risk factors. We investigated the relationship between PWV and bone mass in the lumbar spine in postmenopausal women.

METHODS

We studied the PWV in 95 women; 38 postmenopausal women with normal spinal bone mineral density (BMD), 32 osteopenic postmenopausal women, and 25 osteoporotic postmenopausal women. The brachial-ankle PWV (baPWV) was measured using an automated device. The BMD of the lumbar spine (L2-L4) was measured using dual-energy X-ray absorptiometry.

RESULTS

After adjusting for age and years since menopause, women with osteoporosis had a significantly higher baPWV than those with normal BMD (1500 +/- 220 cm/s versus 1340 +/- 215 cm/s; P < 0.05), but no significant differences in baPWV were seen between the osteoporotic and osteopenic groups or between the osteopenic and normal BMD groups. In univariate regression analysis, the baPWV was significantly negatively correlated with BMD (r = -0.450, P < 0.01), and significantly positively correlated with age (r = 0.601, P < 0.01), years since menopause (r = 0.577, P < 0.01), systolic blood pressure (r = 0.295, P < 0.01), and diastolic blood pressure (r = 0.264, P < 0.05), but was not with other variables. In multivariate regression analysis, the baPWV was significantly correlated with BMD (P < 0.05), but not with other variables.

CONCLUSIONS

Postmenopausal women with osteoporosis may have elevated arterial stiffness, suggesting that osteoporotic postmenopausal women may have a higher risk of cardiovascular disease.

Characteristics of brachial-ankle pulse wave velocity in Japanese children

BACKGROUND

Measurement of pulse wave velocity (PWV) is a useful approach for evaluating the severity of atherosclerosis in adults, and, in particular, the measurement of brachial-ankle PWV (baPWV) has been commonly reported as a simple and practicable method. We attempted to investigate how baPWV in healthy children changes with age and gender, in order to assess baPWV in children with risk factors for the early progression of systemic atherosclerosis.

METHODS

We measured baPWV in 970 healthy Japanese children (500 boys and 470 girls), and set up the normal baPWV values of children on the basis of age and gender. We also performed linear regression analysis and step-wise multiple regression analysis for evaluating its correlation with baPWV and independent variables for baPWV in children.

RESULTS

The values of baPWV in children were higher in boys than in girls, and baPWV increased with age in both genders. Age, blood pressure and heart rate (HR) were significant determinants of baPWV in both male and female subjects, while the obesity index had no correlation with baPWV.

CONCLUSION

On the basis of these results, we suggest that baPWV in children is largely influenced by age and gender, and that baPWV gradually increased with age in both genders.

Change in pulse wave velocity throughout normal pregnancy and its value in predicting pregnancy-induced hypertension: a longitudinal study

OBJECTIVE

We longitudinally examined the changes of brachial to ankle distensibility using pulse wave velocity (PWV) throughout pregnancy and its difference between normal pregnancy and pregnancy-induced hypertension (PIH) groups.

STUDY DESIGN

One hundred and eighty-three pregnant women were included in this study. The PWV examinations were performed in a longitudinal way during the first, second, and third trimesters of pregnancy, and immediately and 1 month after delivery.

RESULTS

In normal pregnancies, the PWV significantly decreased at the second trimester, increased from the third trimester through immediately after delivery, and decreased again at 1 month after delivery. In PIH patients, it increased in proportion to the progression of gestation.

CONCLUSION

We monitored the longitudinal changes in PWV and constructed a PWV normogram during pregnancy. The predictive value of PWV and blood pressure for PIH was higher than that of blood pressure alone, suggesting the usefulness of measuring PWV to predict PIH.

Arterial stiffening and cardiac hypertrophy in a new rat model of type 2 diabetes

BACKGROUND

We determined the effects of NIDDM on haemodynamic parameters describing arterial wall elasticity and cardiac hypertrophy in rats administered streptozotocin (STZ) and nicotinamide (NA), using the aortic impedance analysis.

METHODS

Male Wistar rats at 2 months were administered intraperitoneally 180 mg kg(-1) of NA, 30 min before an intravenous injection of 50 mg kg(-1) STZ, to induce type 2 diabetes. The STZ-NA rats were divided into two groups, 4 weeks and 8 weeks after induction of diabetes, and compared with untreated age-matched controls. Pulsatile aortic pressure and flow signals were measured by a high-fidelity pressure sensor and electromagnetic flow probe, respectively, and were then subjected to Fourier transformation for the analysis of aortic input impedance.

RESULTS

In each diabetic group, the experimental syndrome was characterized by a moderate and stable hyperglycaemia and a relative deficiency of insulin secretion. However, the 8-week but not the 4-week STZ-NA diabetic rats showed a decrease in cardiac output in the absence of any significant changes in mean aortic pressure, having increased total peripheral resistance. The diabetic syndrome at 8 weeks also contributed to an increase in aortic characteristic impedance, from 1.49 +/- 0.33 (mean +/- SD) to 1.95 +/- 0.28 mmHg s mL(-1) (P < 0.05), suggesting a detriment to the aortic distensibility in NIDDM. Meanwhile, the STZ-NA diabetic animals after 8 weeks had an increased wave reflection factor (0.46 +/- 0.09 vs. 0.61 +/- 0.13, P < 0.05) and decreased wave transit time (25.8 +/- 3.8 vs. 20.6 +/- 2.8 ms, P < 0.05). Ratio of the left ventricular weight to body weight was also enhanced in the 8-week STZ-NA diabetic rats.

CONCLUSION

The heavy intensity with early return of the pulse wave reflection may augment systolic load of the left ventricle coupled to the arterial system, leading to cardiac hypertrophy in the rats at 8 weeks after following STZ and NA administration.

Evaluation of Arterial Stiffness in Patients with Branch Retinal Vein Occlusion

PURPOSE

To assess the arterial stiffness in patients with branch retinal vein occlusion (BRVO).

METHODS

Brachial-ankle pulse wave velocity (PWV) and ankle-brachial index were measured in 10 patients with BRVO (mean age 67.9 +/- 7.5 years) and in 18 age-matched controls (mean age 66.9 +/- 6.8 years). The controls were subjects with systemic essential hypertension having no retinal lesions.

RESULTS

The PWV in the BRVO group was 1,946 +/- 254 cm/s which was significantly higher than that in the control group (1,688 +/- 274 cm/s; p = 0.014, Wilcoxon rank sum test). The ankle-brachial indexes were 1.16 and 1.15 in BRVO and control groups, respectively. There was no significant difference between the groups (p = 0.944). In the control group, there was a significant positive correlation between PWV and systolic blood pressure (Spearman correlation coefficient r(s) = 0.385, p = 0.043), while no significant correlation was found in the BRVO group (Spearman correlation coefficient r(s) = -0.188, p = 0.603).

CONCLUSION

The arterial stiffness is increased in patients with BRVO which was thought to be due to the structural changes of the artery and not dependent on the blood pressure.

Association between arterial stiffness and platelet activation

Increased arterial stiffness is strongly associated with atherosclerosis, while platelet activation is an important trigger of thrombotic events in patients with atherosclerosis. However, little is known about the effect of arterial stiffness on platelet activation. We therefore investigated the association between arterial stiffness and platelet activation in 38 normal volunteers (20 men and 18 women) aged 23-77 years (mean = 49 +/- 15 years). Arterial stiffness was assessed by measuring brachial-ankle pulse wave velocity (ba-PWV) and heart-brachial PWV (hb-PWV). Flow cytometric analyses were performed to evaluate platelet activation by measuring surface expression of P-selectin and platelet-neutrophil complexes (PNC) before and after activation by ADP. We also calculated the difference between basal and stimulated states of P-selectin and PNC to assess platelet activation reserve. PWVs were significantly correlated with age and BP (r = 0.60-0.81). For platelet activation and activation reserve, correlations with age were less strong but remained significant (r = 0.36-0.61), with the exception of P-selectin (not significant, NS), and correlations with SBP were similar (r = 0.35-0.53). A significant correlation was found between PWVs and platelet activation (r = 0.43-0.74). Multiple regression analysis demonstrated significant correlations between platelet activation and reserve and PWVs (coefficient = 2.17-6.59), when both age and BP were adjusted for simultaneously. In conclusion, platelet activation was associated with arterial stiffness, suggesting that arterial stiffness may play an important role in thrombotic events.

Relation between aortic stiffness and coronary flow reserve in patients with coronary artery disease

OBJECTIVES

To investigate the relation between aortic stiffness and coronary flow reserve (CFR) in patients with coronary artery disease (CAD).

DESIGN

Observational study.

SETTING

Coronary care unit of a primary care hospital.

PATIENTS

192 consecutive patients who underwent coronary angiography.

MAIN OUTCOME MEASURE

Brachial-ankle pulse wave velocity (ba-PWV), CFR, and severity of CAD.

RESULTS

According to the angiographic findings, patients were divided into four subgroups: patients without significant stenosis (normal coronary artery (NCA) group, n = 28) and those with one vessel disease (1VD group, n = 92), two vessel disease (2VD group, n = 50), or three vessel disease (3VD group, n = 22). ba-PWV increased with the number of diseased vessels and was significantly correlated with the number of diseased vessels (NCA group v 1VD group v 2VD group v 3VD group: 1481 (252) v 1505 (278) v 1577 (266) v 1727 (347) cm/s, p < 0.001). CFR had a significant negative correlation with ba-PWV (r = -0.45, p < 0.0001). The diastolic to systolic velocity ratio obtained in 45 patients also was significantly correlated with ba-PWV (r = -0.35, p < 0.05). Multiple regression analysis showed that ba-PWV was an independent determinant of CFR (p < 0.01).

CONCLUSIONS

Coronary flow is altered with aortic stiffening in patients with CAD. These results suggest one possible mechanism for recent reports that aortic stiffness is a key cardiovascular risk factor.

Endothelial dysfunction: role in obesity-related disorders and the early origins of CVD

Atherosclerotic CVD is the most common cause of death in the West. Yet, its pathogenesis and early development are only partially understood. Central to the early atherosclerotic process is impairment of vascular endothelial function. Endothelial dysfunction can be measured non-invasively and is evident in children before clinical manifestations of atherosclerosis in adulthood. Factors in early life, such as conventional cardiovascular risk factors, or programming by perinatal growth and nutrition strongly affect endothelial function and hence the development of atherosclerosis and CVD. For instance, low birth weight and faster growth early in infancy have a detrimental effect on vascular structure and function. Childhood obesity, a key independent risk factor for CVD, also adversely affects early vascular health. Obesity is associated with endothelial dysfunction and greater arterial stiffness from as early as the first decade of life, while weight loss is beneficial. This effect on vascular function is probably mediated in part by low-grade inflammation and insulin resistance associated with obesity or by the production by adipose tissue of cytokine-like molecules, collectively termed adipokines. A high leptin concentration, in particular, is found in obese individuals and is strongly associated with vascular changes related to early atherosclerosis. The present review focuses on the early origins of endothelial dysfunction, emphasising the role of obesity. It also considers the mechanisms by which obesity impairs endothelial function, understanding of which will be important to further scientific knowledge and to improve public health.

Increased augmentation of central blood pressure is associated with increases in carotid intima-media thickness in type 2 diabetic patients

AIMS/HYPOTHESIS

Type 2 diabetes is associated with a two- to seven-fold increase in cardiovascular morbidity and mortality. The aim of this study was to determine the relationships between intima-media thickness (IMT), an established marker of atherosclerosis, large artery function and other determinants of cardiovascular risk in type 2 diabetic patients.

METHODS

We studied 228 type 2 diabetic patients (75 women, aged 62+/-2 years [mean+/-SEM]). Carotid IMT was bilaterally measured using ultrasound technology. Applanation tonometry and pulse wave analysis were used to measure aortic systolic and diastolic blood pressures, central pressure augmentation (AG) and the augmentation index (AIx), a measure of systemic arterial stiffness. Conventional cardiovascular risk factors (lipids, HbA(1)c, smoking and diabetes duration) were also assessed.

RESULTS

Women had higher AG and AIx (p<0.0001), despite comparable systolic BP and heart rate in women and men. In women, AG (r=0.39, p<0.001), age (r=0.32, p<0.01), brachial systolic BP (r=0.34, p<0.01) and aortic systolic BP (r=0.34, p<0.01) correlated with IMT. In men, age (r=0.41, p<0.001), diabetes duration (r=0.25, p<0.01), AG (r=0.22, p<0.01), aortic systolic BP (r=0.21, p<0.01), brachial systolic BP (r=0.21, p<0.01) and body weight (r=0.16, p<0.05) correlated with IMT. In multiple linear regression analyses, AG and aortic systolic BP, but not brachial systolic BP, were age-independent determinants of IMT in men and women. In all patients, increased AG (adjusted for sex, age and heart rate) correlated with longer duration of diabetes, urinary albumin excretion and IMT.

CONCLUSIONS/INTERPRETATION

Measures of central systolic pressure correlate with carotid IMT, independently of age and other risk markers.

Should diabetes be considered a coronary heart disease risk equivalent?: results from 25 years of follow-up in the Renfrew and Paisley survey

OBJECTIVE

The purpose of our study was to confirm or refute the view that diabetes be regarded as a coronary heart disease (CHD) risk equivalent and to test for sex differences in mortality.

RESEARCH DESIGN AND METHODS

This was a prospective cohort study of 7,052 men and 8,354 women aged 45-64 years from Renfrew and Paisley, Scotland, who were first screened in 1972-1976 and followed for 25 years. All-cause mortality was calculated as death per 1,000 person-years. A Cox proportional hazards model was used to adjust survival for age, smoking habit, blood pressure, serum cholesterol, BMI, and social class.

RESULTS

There were 192 deaths in 228 subjects with diabetes and 2,016 deaths in 3,076 subjects with CHD. The highest mortality was in the group with both diabetes and CHD (100.2 deaths/1,000 person-years in men, 93.6 in women) and the lowest in the group with neither (29.2 deaths/1,000 person-years in men, 19.4 in women). Men and women with diabetes only and CHD only formed an intermediate risk group. The adjusted hazard ratio (HR) for CHD mortality in men with diabetes only compared with men with CHD only was 1.17 (95% CI 0.78-1.74; P = 0.56). Corresponding HR for women was 1.97 (1.27-3.08; P = 0.003).

CONCLUSIONS

Diabetes without previous CHD carries a lifetime risk of vascular death as high as that for CHD alone. Women may be at particular risk. Our data support the view that cardiovascular risk factors in diabetes should be treated as aggressively as in people with CHD.

Arterial stiffness is associated with diabetic retinopathy in type 2 diabetes

The purpose of this study was to investigate the association between arterial stiffness and diabetic retinopathy. The subjects comprised 1004 patients with type 2 diabetes. Pulse-wave velocity (PWV) was used as a marker of arterial stiffness. Clinical characteristics, including PWV and diabetic retinopathy (DR), were investigated in a cross-sectional study. PWV, duration of diabetes, systolic blood pressure and hemoglobin A1c level were all significantly higher in patients with diabetic retinopathy than in individuals without this disorder. The association between brachial-ankle PWV and diabetic retinopathy remained significant after statistical adjustment, with increasing odds ratios (ORs) from the second quartile (OR, 2.09; 95% confidence interval (CI), 1.21-3.61), to the third (OR, 2.80; 95% CI, 1.61-4.86) and fourth (OR, 4.64; 95% CI, 2.54-8.52) quartiles. Diabetic retinopathy was, therefore, associated with arterial stiffness in patients with type 2 diabetes. Our findings also suggested that PWV might be a marker of vascular injury caused by chronic hyperglycemia.