Surrogate Markers Of Cardiovascular Risk Research Articles

Elevation of HDL-C in response to statin treatment is involved in the regression of carotid atherosclerosis.

Atherosclerosis is strongly associated with an increased mortality in subjects with diabetes. The carotid intima-media thickness (IMT) is commonly measured as a surrogate marker for cardiovascular risk. Statins are well-established protective agents against atherosclerosis and reportedly suppress IMT progression in subjects with diabetes. To clarify the effects of statins on subclinical atherosclerosis, we herein investigated changes in the carotid IMT and lipid profiles in a multi-center, prospective, randomized trial. Hypercholesterolemic subjects with type 2 diabetes were randomly assigned to open-label treatment with either pravastatin or pitavastatin. The primary endpoint of this study was the IMT change after 36 months of statin treatment. A total of 97 subjects (51 pitavastatin; 46 pravastatin) completed this 36-month study. The LDL-C decreased significantly from 163.4 ± 27.9 mg/dl at baseline to 100.4 ± 19.6 mg/dl at 36 months in the pitavastatin group and from 159.7 ± 25.6 mg/dl to 118.5 ± 22.1 mg/dl in the pravastatin group. The mean IMT showed moderate regression in both the pitavastatin (-0.070 ± 0.215 mm, P<0.05) and the pravastatin (-0.067 ± 0.260 mm) group. However, there was no significant difference in the IMT change between the two groups. When the two groups were combined, the 36-month change in the mean IMT was significantly associated with HDL-C change (r=-0.24, P= 0.03). Multiple linear regression analysis revealed the change in HDL-C to be an independent variable showing a positive correlation with the carotid IMT reduction. The administration of statins for 3 years to subjects with type 2 diabetes resulted in a significant regression of the carotid IMT. An elevation of the plasma HDL-C with statin treatment was closely related to a regression of atherosclerosis.

Cardiovascular disease risk in women with migraine

BackgroundStudies suggest a higher prevalence of unfavourable cardiovascular risk factors amongst migraineurs, but results have been conflicting. The aim of this study was to investigate traditional and newly recognized risk factors as well as other surrogate markers of cardiovascular risk in obese and normal weight women with migraine.MethodsFifty-nine adult female probands participated in this case–control study. The sample was divided into normal weight and obese migraineurs and age- and body mass index-matched control groups. The following cardiovascular risk factors were analyzed: serum levels of lipids, fasting glucose, and insulin; insulin resistance; blood pressure; smoking (categorized as current, past or never); Framingham 10-year risk of general cardiovascular disease score; C-reactive protein; family history of cardiovascular disease; physical activity; sleep disturbances; depression; and bioelectrical impedance phase angle. The means of continuous variables were compared using Student’s t-test for independent samples or the Mann–Whitney U-test (for 2 groups) and ANOVA or the Kruskal-Wallis test (for 4 groups) depending on the distribution of data.ResultsAll migraineurs were sedentary irrespective of nutritional status. Migraineurs had higher depression scores and shorter sleep duration, and obese migraineurs, in particular, had worse sleep quality scores. Insulin resistance and insulinaemia were associated with obesity, and obese migraineurs had lower HDL-c than normal weight controls and migraineurs. Also, the Framingham risk score was higher in obese migraineurs.ConclusionThese findings suggest that female migraineurs experience marked inactivity, depression, and some sleep disturbance, that higher insulin resistance and insulinaemia are related to obesity, and that obesity and migraine probably exert overlapping effects on HDL-c levels and Framingham 10-year cardiovascular risk.

Does Short-Term Vitamin C Reduce Cardiovascular Risk in Type 2 Diabetes?

Vitamin C is a powerful antioxidant that is potentially useful in the prevention of atherosclerosis in diabetic individuals. However, the mechanism(s) of vitamin C's anti-atherosclerotic effects in vivo are unresolved, and clinical trials in nondiabetic individuals have yielded conflicting results. Therefore, we performed 32 studies in a randomized, crossover, dose-response trial in 8 volunteers with type 2 diabetes to determine the effects of vitamin C on serum vitamin C levels, lipids, inflammation, and coagulation. Well-controlled, type 2 volunteers received, in randomized order for 2-week periods, each of the following: 1) no supplemental vitamin C, 2) low-dose vitamin C (250 mg/day), 3) medium-dose vitamin C (500 mg/day), and 4) high-dose vitamin C (1,000 mg/day). A high-caloric content lunch was ingested during each study arm to enhance oxidative stress. Serum vitamin C levels and atherosclerotic risk factors including lipids and markers of oxidative stress, inflammation, and hypercoagulation were determined. Serum vitamin C levels increased significantly at all dosages. In addition, the high-caloric content meal resulted in acute elevations of glucose, insulin, and triglycerides for several hours postmeal. However, no significant effect of vitamin C was observed on lipid parameters or any of the surrogate markers of oxidative stress, inflammation, or hypercoagulability. Our study suggests that if vitamin C does have anti-atherosclerotic effects in diabetes, it does not exert them through the traditional pathways identifiable by established surrogate markers of cardiovascular risk.

Renal sympathetic denervation: applications in hypertension and beyond

Renal afferent and efferent sympathetic nerves are involved in the regulation of blood pressure and have a pathophysiological role in hypertension. Renal sympathetic denervation is a novel therapeutic technique for the treatment of patients with resistant hypertension. Clinical trials of renal sympathetic denervation have shown significant reductions in blood pressure in these patients. Renal sympathetic denervation also reduces heart rate, which is a surrogate marker of cardiovascular risk. Conditions that are comorbid with hypertension, such as heart failure and myocardial hypertrophy, obstructive sleep apnoea, atrial fibrillation, renal dysfunction, and metabolic syndrome are closely associated with enhanced sympathetic activity. In experimental models and case-control studies, renal denervation has had beneficial effects on these conditions. Renal denervation could become a commonly used procedure to treat resistant hypertension and chronic diseases associated with enhanced sympathetic activation. Current work is focused on refining the techniques and interventional devices to provide safe and effective renal sympathetic denervation. Controlled studies in patients with mild-to-moderate, nonresistant hypertension and comorbid conditions such as heart failure, diabetes mellitus, sleep apnoea, and arrhythmias are needed to investigate the capability of renal sympathetic denervation to improve cardiovascular outcomes.

Association between serum cholesterol and eating behaviours during early childhood: a cross-sectional study

Modifiable behaviours during early childhood may provide opportunities to prevent disease processes before adverse outcomes occur. Our objective was to determine whether young children's eating behaviours were associated with increased risk of cardiovascular disease in later life. In this cross-sectional study involving children aged 3-5 years recruited from 7 primary care practices in Toronto, Ontario, we assessed the relation between eating behaviours as assessed by the NutriSTEP (Nutritional Screening Tool for Every Preschooler) questionnaire (completed by parents) and serum levels of non-high-density lipoprotein (HDL) cholesterol, a surrogate marker of cardiovascular risk. We also assessed the relation between dietary intake and serum non-HDL cholesterol, and between eating behaviours and other laboratory indices of cardiovascular risk (low-density lipoprotein [LDL] cholesterol, apolipoprotein B, HDL cholesterol and apoliprotein A1). A total of 1856 children were recruited from primary care practices in Toronto. Of these children, we included 1076 in our study for whom complete data and blood samples were available for analysis. The eating behaviours subscore of the NutriSTEP tool was significantly associated with serum non-HDL cholesterol (p = 0.03); for each unit increase in the eating behaviours subscore suggesting greater nutritional risk, we saw an increase of 0.02 mmol/L (95% confidence interval [CI] 0.002 to 0.05) in serum non-HDL cholesterol. The eating behaviours subscore was also associated with LDL cholesterol and apolipoprotein B, but not with HDL cholesterol or apolipoprotein A1. The dietary intake subscore was not associated with non-HDL cholesterol. Eating behaviours in preschool-aged children are important potentially modifiable determinants of cardiovascular risk and should be a focus for future studies of screening and behavioural interventions.

Identifying a high risk cardiovascular phenotype by carotid MRI-depicted intraplaque hemorrhage

Intraplaque hemorrhage (IPH), a component of late-stage complicated plaque, identified within carotid endarterectomy surgical specimens has been recently demonstrated to predict cardiovascular (CV) events. MRI is able to depict carotid IPH. We investigated the ability of carotid MR-depicted IPH (MR-IPH) to identify high-risk CV patients. From January 2008 to April 2011, 216 patients (mean age, 67.5 years; range 31-100) referred for neurovascular MRI at an academic tertiary care centre, underwent 3T carotid MRI with adjunct 3D high-spatial-resolution coronal imaging to detect MR-IPH. Five experienced neuroradiologists made a binary decision on the presence or absence of MR-IPH. Patients' charts were reviewed blindly for demographic and CV outcomes data. Of the patients with and without MR-IPH, 62.5 % (15/24) and 19.8 % (38/192) had a composite CV event (defined as a past myocardial infarction, coronary intervention (i.e., angioplasty, stenting or bypass graft) and/or peripheral vascular disease), respectively. The odds ratio (OR) of a composite CV event in the MR-IPH group was 6.75 (Bivariable analysis, 95 % CI 2.75-16.6, p < 0.0001) and 3.25 (Multivariable regression analysis, 1.14-9.37, p = 0.028). MR-IPH had the highest OR of a prior CV event compared to other variables including age, sex, hypertension and stenosis. The OR of individual CV events was also significant: MI (3.35, 95 % CI 2.11-14.2, p < 0.01), coronary stenting (26.4, 95 % CI 8.80-79.4, p < 0.01), coronary angioplasty (21, 95 % CI 4.84-91.1, p < 0.01), and PVD (3.35, 95 % CI 1.09-10.3, p < 0.05). MR-IPH is independently associated with prior CV events in patients who are evaluated for neurovascular disease. Carotid MR-IPH, employed easily in routine clinical practice, is emerging as an indicator of systemic vascular disease and may potentially be a useful surrogate marker of CV risk including in those already undergoing neurovascular imaging.

Carotid intima‐media thickness increase in patients with habitual simple snoring and obstructive sleep apnea syndrome is associated with metabolic syndrome

Sleep disorders are emerging risk factors for atherosclerosis. Increased carotid intima-media thickness (CCA-IMT) is a surrogate marker of cardiovascular risk. The aim of the present study was to investigate the relationship between CCA-IMT and habitual simple snoring or obstructive sleep apnea syndrome (OSAS) and the other cardiovascular risk factors. Sleep disorders were diagnosed and staged by polysomnography. Patients were then classified into either habitual simple snoring (n = 20, group 1) or OSAS (n = 67, group 2), which was subclassified as mild-moderate (n = 27) or severe (n = 40). CCA-IMT was measured by B-mode ultrasonography. The other major risk factors were investigated. The mean CCA-IMT was 0.65 ± 0.02 mm (mean ± SD) in group 1 versus 0.75 ± 0.02 mm in group 2 (p = 0.03). Using CCA-IMT ≥ 0. 9 mm as the threshold value also yielded significant results between the two groups (p = 0.03). The mean CCA-IMT did not differ between patients with mild-moderate and severe OSAS, whereas metabolic risk factors and metabolic syndrome (MS) were more prominent in the latter. Age, MS, neck and waist circumference, waist/ hip circumference, and fasting glucose level were higher in patients with CCA-IMT ≥ 0.9 mm. CCA-IMT increase was associated with OSAS, but did not correlate with its severity, which could be due to the higher incidence of MS in this group.

White Matter Hyperintensities in Recently Menopausal Women Are Associated with Platelet-Derived Surrogate Markers of Cardiovascular Risk (IN8-1.002)

White Matter Hyperintensities in Recently Menopausal Women Are Associated with Platelet-Derived Surrogate Markers of Cardiovascular Risk (IN8-1.002)

White Matter Hyperintensities in Recently Menopausal Women Are Associated with Platelet-Derived Surrogate Markers of Cardiovascular Risk (S29.007)

White Matter Hyperintensities in Recently Menopausal Women Are Associated with Platelet-Derived Surrogate Markers of Cardiovascular Risk (S29.007)

Association of Lipoprotein Subfractions and Coronary Artery Calcium In Patient at Intermediate Cardiovascular Risk

More precise estimation of the atherogenic lipid parameters could improve identification of residual risk beyond what is possible using traditional lipid risk factors. The aim of the present study was to explore the association between advanced analysis of lipoprotein subfractions and the prevalence of coronary artery calcium. Consecutive participants at intermediate cardiovascular risk who were undergoing computed tomographic assessment of coronary calcium (calcium score) were included. Using a validated ultracentrifugation method (the vertical autoprofile II test), cholesterol in eluting lipoprotein subfractions [i.e., low- (LDL), very-low-, intermediate-, and high-density lipoprotein subclasses, lipoprotein (a), and predominant LDL distribution] was directly quantified. A total of 410 patients were included (29% women, mean age 57 years), of whom 297 (72.4%) had coronary artery calcium. LDL pattern B (predominance of small dense particles) emerged as an independent predictor of coronary calcium after adjustment for traditional risk factors (odds ratio 4.46, 95% confidence interval 1.19 to 16.7). However, after additional stratification for dyslipidemia, as defined by conventional lipid profiling, a statistically significant prediction was only retained for high-density lipoprotein subfraction 2 (odds ratio 3.45, 95% confidence interval 2.03 to 50.1) and "real" LDL (odds ratio 6.10, 95% confidence interval 1.26 to 23.41) in the normolipidemia group and for lipoprotein (a) (odds ratio 7.81, 95% confidence interval 1.41 to 43.5) in the dyslipidemic group. In conclusion, advanced assessment of the lipoprotein subfractions [i.e., LDL pattern B, high-density lipoprotein subfraction 2, "real" LDL, and lipoprotein (a)] using the vertical autoprofile II test provided additional information to that of conventional risk factors on the prevalence of coronary artery calcium in patients at intermediate cardiovascular risk.

Markers of visceral obesity and cardiovascular risk in patients with polycystic ovarian syndrome

Polycystic ovarian syndrome (PCOS) is one of most common endocrine disturbances in women of reproductive age. Besides its well known effects on reproductive health, it is also linked to increased cardiovascular risk in later life. The aim of this study was to investigate the link between some anthropometric indices of visceral obesity and surrogate markers of cardiovascular risk according to the Androgen Excess and Polycystic Ovary Syndrome (AE-PCOS) Society consensus. The study included 36 normal weight (BMI<25 kg/m²) and 19 obese PCOS subjects (BMI ≥ 30 kg/m²), aged between 18 and 40 years. Different anthropometric markers were compared as predictors for an adverse cardiometabolic profile and composite cardiovascular risk factors as defined by the AE-PCOS consensus. Both waist-to-stature ratio (WSR) (area under the curve 0.75, p=0.002) and waist circumference (WC) (area under the curve 0.77, p=0.001) but not waist-to-hip ratio (WHR) (area under the curve 0.62, p=0.143) were shown to be good markers of increased cardiovascular risk, insulin resistance and dislipidemia in PCOS patients. The cut-off point for WSR of 0.50 is useful and the cut-off of 80 cm for WC is more appropriate than 88 cm in detecting cardiovascular risk in PCOS patients. Androgen levels and immunoreactive insulin during an oral glucose tolerance test had lower power for predicting increased cardiovascular risk than WC and WSR. The study indicates that WSR and WC are better associated with composite cardiovascular risk factors as defined by the AE-PCOS consensus than WHR, and that the commonly used cut-off for WSR of 0.5 is useful for detecting cardiovascular risk in PCOS patients.

Impact of endovascular treatment of atherosclerotic renal artery stenosis on endothelial function and arterial blood pressure.

Renovascular disease may cause arterial hypertension and decreases renal function, which both impair endothelial function. Endothelial function, a surrogate marker for cardiovascular risk, can be assessed non-invasively by ultrasound. The aim of this study was to investigate the impact of percutaneous transluminal renal artery angioplasty (PTRA) with stenting on endothelial function and arterial blood pressure in patients with renal artery stenosis (RAS). Flow mediated dilatation of the brachial artery, flow velocities and shear stress were measured with high resolution ultrasound in 24 hypertensive patients with renal artery stenosis prior and one day after revascularization by PTRA with stenting. Endothelial-independent brachial dilatation was measured after application of nitroglycerin. Endothelial-dependent dilatation improved from 2.4±0.9% to 6.1±1.4% (P=0.03), whereas endothelial-independent dilatation did not change after PTRA. Endothelial-dependent reactive hyperemic blood flow increased from 195±40 mL/min to 536±94 mL/min (P=0.0008), whereas endothelial-independent hyperemia did not increase after revascularization. After PTRA, shear stress at rest decreased from 37±11 to 23±3 dyne/cm² (P<0.0001), and reactive hyperemic shear stress increased from 89±29 to 107±12 dyne/cm² (P=0.014). The impact of PTRA on arterial blood pressure resulted in a mean decrease of 21±5 mmHg in systolic pressure (P<0.0001), of 9±2 mmHg in diastolic pressure (P=0.03), and of 14±5 mmHg in peripheral pulse pressure (P=0.0003), respectively. Endovascular treatment of renovascular disease improves endothelial function and decreases in resting shear stress.

Exenatide Extended-Release

Subcutaneous exenatide extended-release (ER; Bydureon™; also known as exenatide once weekly), a glucagon-like peptide-1 receptor agonist, provides a convenient, simple, once-weekly regimen that is approved in adult patients with type 2 diabetes as adjunctive monotherapy to diet plus exercise (in the US; not as first-line therapy) and/or as combination therapy with specific oral antihyperglycaemic drugs (OADs) in patients with inadequately controlled type 2 diabetes despite treatment with these OADs (US and Europe). This article reviews the clinical efficacy and tolerability of exenatide ER in the treatment of adult patients with type 2 diabetes and gives a brief overview of its pharmacological properties. In several short-term (24-30 weeks) well designed trials, adjunctive subcutaneously injectable exenatide ER once weekly, as monotherapy or in combination with OADs, significantly improved glycaemic control, bodyweight and some surrogate markers of cardiovascular risk in adult patients with inadequately controlled type 2 diabetes despite diet and exercise and/or treatment with OADs. Furthermore, the beneficial effects of adjunctive exenatide ER therapy were sustained in extension studies of up to 3 years of treatment. Overall, the intensity of glycaemic control with exenatide ER was generally better than that observed with the exenatide immediate-release formulation (twice daily), sitagliptin or insulin glargine. Exenatide ER was shown to be noninferior to metformin in terms of glycaemic efficacy, but did not meet the criteria for noninferiority versus liraglutide. In treatment-naive patients, exenatide ER treatment did not meet noninferiority criteria versus pioglitazone, whereas in treatment-experienced patients, exenatide ER provided better glycaemic control than pioglitazone. Improvements in glycaemic control with exenatide ER and, in general, with other antihyperglycaemic agents were reflected in significant improvements from baseline in treatment satisfaction and health-related quality-of-life measures. Exenatide ER was generally well tolerated in patients participating in these trials, with most treatment-emergent adverse events being of a gastrointestinal nature, of mild to moderate severity, transient and of a similar nature and incidence to those occurring with the exenatide immediate-release formulation. Thus, exenatide ER is a useful option for the treatment of type 2 diabetes, particularly in patients where bodyweight loss is an essential aspect of the individual patient's management.

Can HbA1c act as a surrogate marker for cardiovascular risk?

AIM:. Glycosylated hemoglobin is a used marker for long-term glycemic control.This investigation is an attempt to evaluate the diagnostic value of HbA(1c) in predicting cardiovascular risk MATERIALS AND METHODS: The study was conducted in Dr PSIMS&RF,Vijayawada. 278 subjects during May 2012 to October 2012, were included in the study Details regarding to age, gender, duration of diabetes, were taken. Venous blood samples were collected and analyzed for glycosylated hemoglobin (HbA1c), fasting plasma glucose (FPG) , Total Cholesterol, Triglycerides, HDL-C and LDL-C and AIP RESULTS: The total cholesterol and LDL cholesterol were significantly higher in females as compared to male diabetics. TG levels and AIP ratio were raised in the subjects 55 years. In cases with duration of diabetes > 6 years HbA1c, total cholesterol, TG, LDL cholesterol and AIP ratio were elevated but only total cholesterol and LDL cholesterol were statistically significant. All the lipid parameters except HDL cholesterol were higher in subjects with HbA1c >7 % as compared to the group with HbA1c < 7%. CONCLUSION: The findings indicate that HbA1c can provide auxiliary information about the extent of circulating lipids and AIP, and can thus be used as a predictor of cardiovascular risk in diabetics

Coronary artery calcium scoring and its impact on the clinical practice in the era of multidetector CT

With the suggestion of coronary artery calcium as an indicator of coronary artery disease 30 years ago, intense and controversial discussion regarding coronary artery calcium has been ongoing. Diverse techniques for evaluation of coronary artery calcium were suggested and validation of its feasibility has been followed up. Following establishment of reference standards, coronary artery calcium became widely utilized in clinical practice and scientific research. Originally coronary artery calcium scoring techniques were developed for prediction of cardiovascular risk. Additionally, coronary artery calcium scoring has been utilized as an indicator for other medical events. Recently, coronary artery calcium scoring used to be applied as a reference standard during scientific research. In this article, the topic of coronary artery calcium, from its introduction to its current usefulness, was discussed from the viewpoints of coronary artery calcium scoring techniques, imaging modalities, validation of the techniques, clinical feasibility of coronary artery calcium scoring beyond traditional cardiovascular risk prediction, and utilization of coronary artery calcium scoring as a reference standard. Popular coronary calcium scoring techniques comprises of Agatston, volume, and mass scores. Through validation of these techniques, pros and cons of each technique were analyzed and proper utility could be suggested. In parallel, the reference standards for Agatston and volume scores were established by age, sex, and race. Through the vigorous controversies, nowadays, the clinical feasibility of coronary artery calcium score as a surrogate marker of cardiovascular risk was acknowledged in the literature.

Impact of Cholecalciferol Treatment on Biomarkers of Inflammation and Myocardial Structure in Hemodialysis Patients Without Hyperparathyroidism

Vitamin D (25-hydroxyvitamin D, 25(OH)D) deficiency, hypovitaminosis D, is highly prevalent in chronic kidney disease patients and is potentially involved with complications in the hemodialysis (HD) population. The aim of this study was to evaluate the impact of cholecalciferol supplementation on biomarkers of mineral metabolism, inflammation, and cardiac function in a group of HD patients presenting with hypovitaminosis D and low intact parathyroid hormone (iPTH) levels. HD patients with iPTH levels of <300 pg/mL, not receiving vitamin D therapy, and presenting with 25(OH)D levels of <30 ng/mL were enrolled in this prospective study. Oral cholecalciferol was prescribed once a week in the first 12 weeks (50,000 IU) and in the last 12 weeks (20,000 IU) of the study. High-sensitivity C-reactive protein, interleukin-6, and serum albumin were used as inflammatory markers. Echocardiograms were performed on a midweek interdialytic day at baseline and after 6 months of cholecalciferol supplementation. In all, 30 patients were included in the final analysis. We observed a significant increase in serum 25(OH)D levels after 3 months (46.2 ± 14.4 ng/mL vs. 18.1 ± 6.6 ng/mL; P < .001) and after 6 months (40.4 ± 10.4 ng/mL vs. 18.1 ± 6.6 ng/mL; P < .001) of cholecalciferol supplementation. There were no significant changes in alkaline phosphatase, iPTH, phosphorus, and serum albumin levels, but there was a slight but significant increase in calcium levels after 6 months of cholecalciferol supplementation (9.4 ± 0.6 mg/dL vs. 9.0 ± 0.6 mg/dL; P = .02). Additionally, we observed a significant reduction in high-sensitivity C-reactive protein levels after 3 months (median: 0.62 [0.05 to 29.6] mg/L vs. 0.32 [0.02 to 3.13] mg/L; P = .02) and after 6 months (median: 0.62 [0.05 to 29.6] mg/L vs. 0.50 [0.02 to 5.66] mg/L; P = .04) of cholecalciferol supplementation, as well as a significant reduction in interleukin-6 levels (median: 6.44 pg/mL vs. 3.83 pg/mL; P = .018) after 6 months of supplementation. Left ventricular mass index was significantly reduced at the end of supplementation (159 ± 55 g/m(2) vs. 175 ± 63 g/m(2); P = .03). Cholecalciferol supplementation in HD patients was found to be safe and efficient to correct hypovitaminosis D and established little impact on mineral metabolism markers. Additionally, we observed a reduction in important surrogate markers of cardiovascular risk, namely systemic inflammation and left ventricular hypertrophy, suggesting an anti-inflammatory action and possibly an improvement of cardiac dysfunction.

Short-Term Effect of Atorvastatin on Carotid Artery Elasticity

Few studies have examined the early effects of statins on carotid artery elasticity, a potential surrogate marker of cardiovascular risk. This study examined the short-term effects of atorvastatin 80 mg daily on carotid elasticity measured by high-resolution B-mode ultrasound. The study included 40 stroke-free and statin-naive subjects older than age 45 (mean age, 70±7 years; 55% men; 64% Caribbean-Hispanic). Outcome measures included carotid stiffness indices at 14 and 30 days after initiation of treatment. The systolic and diastolic diameters of the right common carotid artery were averaged from multiple B-mode imaging frames. Absolute and relative changes of strain [(systolic diameter-diastolic diameter)/diastolic diameter], stiffness (β) [ln (systolic/diastolic blood pressure)/strain], and distensibility (1/β adjusted for wall thickness) from baseline were compared by the repeated measures t test and were considered significant at α=0.05. Baseline mean stiffness was 0.08 (95% confidence interval [CI], 0.06-0.10). It significantly decreased at day 30 to 0.05 (CI, 0.04-0.06; P<0.01). Mean baseline distensibility was 15.25 (CI, 13.18-17.32), increasing significantly at day 30 to 17.23 (CI, 14.01-20.45; P<0.05). An improvement in distensibility of ≥10% from baseline was observed in 29 (73%) subjects. Changes in stiffness and distensibility were maximal among subjects with baseline low-density lipoprotein levels<130 mg/dL. Short-term treatment with high-dose atorvastatin was associated with improvement in the carotid elasticity metrics. Carotid artery elasticity measured by B-mode ultrasound is a simple noninvasive measure of arterial wall function and may be a useful surrogate end point in clinical trials targeting individuals at increased risk for atherosclerosis.

Comparison of Peripheral Endothelial Function in Shift Versus Nonshift Workers

Shift working is related to increased cardiovascular morbidity. Peripheral endothelial dysfunction, an inherent feature of early atherosclerosis, has been suggested as a surrogate marker of cardiovascular risk. Whether shift working is associated with peripheral endothelial dysfunction has not been investigated to date. A total of 48 male shift workers (SWs) and 47 male nonshift workers (NSWs) (mean age 43 ± 5 years) were recruited from a glass manufactory. The SWs and NSWs were matched according to age, body mass index, smoking habits, family history of premature coronary artery disease, prevalence of hypercholesterolemia and hypertension, and work place. Their sport habits were also documented. Peripheral endothelial function was assessed using the EndoPAT technique to determine the peripheral arterial tone (PAT) index. According to the study design, no difference was found in the risk factor profiles between the SWs and NSWs. Despite a greater percentage of regular physical activity among the SWs (16.7 vs 4.3%, p = 0.05), shift working was associated with a reduced PAT index compared to working only on the day shift (PAT index 1.73 ± 0.4 vs 1.94 ± 0.5, p = 0.03). In the NSW group, the participants with regular physical training (n = 16) had a greater PAT index than those without regular physical activity (n = 12; PAT index 2.28 ± 0.45 vs 1.86 ± 0.51, p = 0.03). No such difference was found in the SWs. In conclusion, SWs had a reduced PAT index compared with NSWs, suggesting endothelial dysfunction. Therefore, the known increased cardiovascular risk in those shift working might be related to endothelial dysfunction.

Correlation between postischemic vasodilation of the arteria brachialis and of the postischemic hyperemia in the adjacent microvascular bed

Endothelial cells secrete different mediators depending on biochemical and/or biophysical conditions, which can lead to vasodilation or vasoconstriction, respectively. Impaired endothelial responsiveness to specific vasodilator stimuli has been used as a surrogate marker of cardiovascular risk. Multiple methods allow testing endothelial responses in both microvessels and conduit arteries, but it is still unclear whether there is a relationship in endothelial function between these two different vascular beds. In order to examine, whether such macrocirculatory data might correlate with data obtained in the supplied microvessels, a parallel investigation in the brachial artery (BA) and the supplied nailfold capillaries was performed. The duration and amplitude of the postischemic hyperemia (stasis in the vasculature of the left arm using a blood pressure cuff for 3 minutes) were measured (ultrasound technique) and simultaneously the amplitude and duration of the postischemic hyperemia in ipsilateral nailfold capillaries (intravital capillaroscopy). There was absolutely no correlation between the duration (n = 153, r = 0.076, p = 0.3493) of the diameter increase in the BA and in ipsilateral nailfold capillaries. The regulation of the cutaneous microcirculation did not follow diameter changes of the conduit artery (BA) but seems to be dominated by the precapillary arterioles.

Diabetes News.

Diabetes News.