Early-stage predictors of the acute phase duration in uncomplicated COVID-19 pneumonia.

OBJECTIVE: In this study, we aimed to highlight the common early-stage clinical and laboratory variables independently related to the acute phase duration in patients with uncomplicated coronavirus disease (COVID-19) pneumonia. METHODS: In hospitalized patients, the acute phase disease duration was followed using the Brescia-COVID respiratory severity scale. Noninvasive ventilation was administered based on clinical judgment. Patients requiring oropharyngeal intubation were excluded from the study. For parameters to be measured at the hospital entrance, age, clinical history, National Early Warning Score 2 (a multiparametric score system), partial pressure of oxygen in arterial blood/fraction of inspired oxygen (P/F ratio), C-reactive protein, and blood cell count were selected. RESULTS: In 64 patients, age (direct relationship), P/F, and platelet number (inverse relationship) independently accounted for 43% of the acute phase duration of the disease (P < .001). CONCLUSIONS: For the first time, the present results revealed that the acute phase duration of noncomplicated pneumonia, resulting from severe acute respiratory syndrome coronavirus 2, is independently predicted from a patient's age, as well as based on the hospital entrance values of P/F ratio and peripheral blood platelet count.

Blood viscosity but not shear stress associates with delayed flow-mediated dilation.

PURPOSE: Flow-mediated dilation (FMD) is a complex mechanism involving several mediators, and different hemodynamic forces. Temporally distinct FMD patterns can be elicited by ischemic stimulus. Some subjects dilate early after cuff release, while others dilate later or do not dilate at all. Aim of the present research was to verify if hemorheological and hemodynamic factors might influence different FMD pattern. METHODS: 148 free-living subjects were studied. FMD was measured at 50 s, 2 min and 3 min. Blood viscosity was measured and shear stress calculated. Shear stress stimulus was quantified as the area under the curve after ischemia (SSAUC) over the first 40-s post-occlusion. RESULTS: Based on the timing or absence of arterial dilation, 82 subjects were classified as Early dilators, 37 as Late dilators and 29 as No dilators. Peak FMD was 7.9 ± 4.3 % in Early dilators, and 9.1 ± 5.7 in Late dilators (p = NS). SSAUC was not significantly different among three groups, while blood viscosity was significantly higher in Late FMD subjects. Regression analyses showed the independent predictive role of age and blood viscosity on FMD patterns, and the lack of any association between FMD pattern and the magnitude of SS. CONCLUSIONS: The present study demonstrates that age and blood viscosity but not the magnitude of SS explain the different timing of the dilatory response to ischemia.

Delayed vasodilation is associated with cardiovascular risk.

BACKGROUND: Flow-mediated dilation (FMD) of the brachial artery is widely used to assess cardiovascular risk. In recent years, much attention has been paid to the kinetics of vasodilation in an attempt to better characterize the endothelial function. Here, we investigated whether FMD magnitude and/or latency are most related to individual cardiovascular risk. MATERIALS AND METHODS: Four hundred subjects were recruited. Individual risk prediction was estimated by Framingham cardiovascular risk score and CUORE project calculator. Subjects were divided into Early dilators (peak FMD at 50 s), Late dilators (peak FMD over 50 s) and No dilators. RESULTS: Cardiovascular risk was highest in No dilators and significantly higher in Late than Early dilators despite comparable peak FMD. When divided according to peak FMD quintiles, Early and Late dilators showed decreased cardiovascular risk with increasing magnitude of vasodilation. However, subjects in the first three quintiles of Late dilators had a markedly higher risk score despite a peak vasodilation similar to that of Early dilators. CONCLUSION: These results suggest that the magnitude of the FMD and its latency are both important for identifying patients at risk of cardiovascular disease. Subjects with a delayed though significant vasodilation associated with a blunted early response exhibit the highest cardiovascular risk.

Lipid-polymer nanoparticles encapsulating curcumin for modulating the vascular deposition of breast cancer cells.

Vascular adhesion and endothelial transmigration are critical steps in the establishment of distant metastasis by circulating tumor cells (CTCs). Also, vascular inflammation plays a pivotal role in steering CTCs out of the blood stream. Here, long circulating lipid-polymer nanoparticles encapsulating curcumin (NANOCurc) are proposed for modulating the vascular deposition of CTCs. Upon treatment with NANOCurc, the adhesion propensity of highly metastatic breast cancer cells (MDA-MB-231) onto TNF-α stimulated endothelial cells (HUVECs) reduces by ~70%, in a capillary flow. Remarkably, the CTCs vascular deposition already reduces up to ~50% by treating solely the inflamed HUVECs. The CTCs arrest is mediated by the interaction between ICAM-1 on HUVECs and MUC-1 on cancer cells, and moderate doses of curcumin down-regulate the expression of both molecules. This suggests that NANOCurc could prevent metastasis and limit the progression of the disease by modulating vascular inflammation and impairing the CTCs arrest. FROM THE CLINICAL EDITOR: In this novel study, lipid nanoparticles encapsulating curcumin were able to prevent metastasis formation and limited the progression of the disease by modulating vascular inflammation and impairing the circulating tumor cells' arrest as a result of down-regulation of ICAM1 and MUC1 in a highly metastatic breast cancer cell line model.

Delayed flow-mediated vasodilation and carotid atherosclerosis.

BACKGROUND: In a previous study, we identified temporally distinct postischaemic flow-mediated dilation (FMD) patterns comparing the standard clinical measurement time of 50s postcuff release with measurement at 2 min. The comparison revealed a cohort with the highest FMD at 50s (Early FMD), another cohort with the highest FMD at 2 min (Late FMD) and a third cohort with no FMD (Absent FMD). The aim of this study was to examine whether these temporally distinct FMD patterns associated with different degrees of carotid atherosclerosis. MATERIALS AND METHODS: One hundred and twenty-four free-living white subjects, participating in a cardio-vascular disease prevention campaign, were enrolled. FMD was measured at 50s, 2 min and 3 min after forearm ischaemia. The intima-media thickness (IMT) of the common carotid artery was measured, and the artery was evaluated for the presence and number of carotid plaques. RESULTS: Fifty-seven subjects had Early FMD, 34 had Late FMD and 33 had Absent FMD. The three groups were comparable for age, sex and cardiovascular risk factors. The number of plaques in the carotid arteries, and IMT, increased progressively from Early, to Late, and to Absent FMD (P < 0·03), indicating that the FMD pattern is an independent predictive variable for IMT and carotid atherosclerosis. CONCLUSIONS: The present study demonstrates that temporal patterns associated with the degree of atherosclerosis of the carotid arteries. Patients with delayed vasodilation (Late FMD) had a higher degree of atherosclerosis than those with early vasodilation (Early FMD), and subjects with no postischaemic vasodilation (Absent FMD) had the most atherosclerosis.

Common carotid and brachial artery hemodynamic alterations in periodontal disease.

AIM: In patients affected by periodontal disease, hypertension and systemic inflammation might cause an arterial hemodynamic derangement; this, in turn, can act as a mediator of the atherogenic process often seen in these patients. This study aimed at a comprehensive hemodynamic evaluation in periodontal patients. METHODS: Fourty-eight subjects participating to a cardiovascular prevention programme were enrolled. Periodontitis, classical risk factors for atherosclerosis, and shear and tensile forces in both carotid and brachial arteries were evaluated. Calculated periodontal indexes were plaque, gingival and pocket deep (PD) indexes. Simple and multiple regression analyses were performed. Afterwards, 30 of them with normal PD index were compared with 30 carefully - matched patients with periodontitis. RESULTS: Brachial and carotid parietal tension were significantly associated with periodontal indexes, especially PD-Sum, in both simple (r = 0.42, p < 0.001 for carotid artery and r = 0.36, p < 0.02 for brachial artery) and multiple regression analyses. Shear stress gave similar results. In case-control analysis, shear stress was lower by 15% and 30%, respectively, in carotid and brachial artery in patients with high PD; common carotid parietal tension was higher. Arterial stiffness resulted not associated with periodontitis. CONCLUSIONS: Periodontal disease is associated to a complex atherosclerotic prone hemodynamic derangement, particularly in large elastic arteries.

Effects of Vitamin D Supplementation in Patients with Statin-Associated Muscle Symptoms and Low Vitamin D Levels.

Background: Statin therapy is a cornerstone of cardiovascular disease treatment and prevention. Unfortunately, 7%-29% of statin-treated patients complain of muscular fatigue, cramps, and/or pain (statin-associated muscle symptoms [SAMS]). In recent years, the important role of vitamin D in muscle health maintenance has been highlighted. In addition, hypovitaminosis D is very prevalent, and might be a reversible risk factor for SAMS occurrence. Methods: In our controlled intervention study, patients suffering from both SAMS and hypovitaminosis D underwent vitamin D replacement for 6 months. SAMS intensity and its impact on the quality of life were evaluated with a questionnaire during follow-up. A subgroup of patients who were not at the low-density lipoprotein cholesterol (LDL-C) target attempted a statin rechallenge after 3 months. Control subjects, with SAMS only, were not treated. Results: Blood vitamin D levels reached 261% of baseline values. Pain intensity was reduced by 63%, and all life quality indicators improved. At follow-up, percentage variations in SAMS intensity and in vitamin D levels were inversely related (r = 0.57, P = 0.002). In a multiple regression analysis, this association was found to be independent. Among the rechallenge subgroup, 75% successfully tolerated high-intensity statins during the follow-up. The parameters of interest were unchanged in control subjects. Conclusions: In our findings, the amount of increase in vitamin D concentrations is directly related to SAMS improvement. Although randomized studies are needed, 25(OH)D levels can be measured, and eventually supplemented, in all patients suffering from SAMS, and this can be done together with a statin rechallenge after 3 months for patients who are not at the LDL-C target. Register: The study protocol was registered with the EudraCT clinical trial register [ID: 2019-003250-83] in date April 8, 2020.

Autoimmune thyroiditis and celiac disease do not worsen endothelial function in subjects with type 1 diabetes: an observational study.

BACKGROUND: Type 1 diabetes (T1D) is frequently associated with autoimmune thyroiditis (AT) and coeliac disease (CD). Whether the coexistence of multiple autoimmune diseases increases cardiovascular risk is uncertain. We evaluated the effects of AT and CD on arterial wall thickening and endothelial function in patients with T1D. METHODS: This observational study analyzed data from T1D patients regularly followed by the Diabetes Care Centre. Clinical and biochemical characteristics and micro and macrovascular complications were collected from the electronic medical records. All subjects performed Echo-Doppler to evaluate Intima-Media Thickness (IMT) of the common carotid artery (CCA) and endothelial function by the flow-mediated dilation (FMD) technique. The statistical analyses were performed by SPSS for Macintosh. Comparison between means was performed using the t-test for unpaired data and the Mann-Whitney U test. The ANalysis Of VAriance and the Tukey posthoc test were applied to compare patients with and without other autoimmune diseases, and control subjects. The p-value for statistical significance was set at p < 0.05. RESULTS: A total of 110 patients were enrolled. Among these, 69 had T1D and 41 T1D and AT and or CD, of whom 33 AT, 7 CD, and 1 both AT and CD. The mean age was 35 years, mean HbA1c was 7.6%, and mean diabetes duration 18 years. The IMT of the CCA was not significantly different between T1D patients with and without concomitant autoimmune diseases (with AT and CD: right CCA 603 ± 186 µ, left 635 ± 175 µ; without AT and CD: right CCA 611 ± 176 µ, left CCA 631 ± 200 µ). FMD was also comparable between T1D groups, with AT and CD 7.9 ± 4.2%; without AT and CD 8.8 ± 4.4%. CONCLUSION: Patients with T1D and concomitant AT and or CD show no worse morphological or functional vascular damage, evaluated by CCA IMT and brachial artery flow-mediated dilation, than patients with T1D alone.

Higher heparin dosages reduce thromboembolic complications in patients with COVID-19 pneumonia.

Coronavirus disease 2019 (COVID-19) is a new viral disease complicating with acute thrombophylic conditions, probably also via an inflammatory burden. Anticoagulants are efficacious, but their optimal preventive doses are unknown. The present study was aimed to compare different enoxaparin doses/kg of body weight in the prevention of clot complications in COVID-19 pneumonia. Retrospective data from a cohort of adult patients hospitalized for COVID-19 pneumonia, never underwent to oropharyngeal intubation before admission, were collected in an Internal Medicine environments equipped for non-invasive ventilation. Unfavorable outcomes were considered as: deep venous thrombosis, myocardial infarction, stroke, pulmonary embolism, cardiovascular death. Fourteen clinical thromboembolic events among 42 hospitalized patients were observed. Patients were divided into two group on the basis of median heparin dose (0.5 mg-or 50 IU-for kg). The decision about heparin dosing was patient by patient. Higher enoxaparin therapy (mean 0.62±0.16 mg/kg) showed a better thromboprophylactic action (HR=0.2, p=0.04) with respect to lower doses (mean 0.42±0.06 mg/kg), independently from the clinical presentation of the disease. Therefore, COVID-19 pneumonia might request higher enoxaparin doses to reduce thromboembolic events in hospitalized patients, even if outside intensive care units.

Influence of acute reduction of blood viscosity on endothelial function.

BACKGROUND: The relationship between blood viscosity (BV) and endothelial function is rather complex. An increase in BV causes an increase in blood flow resistance, with negative hemodynamic effects; on the other hand, a moderate increase in BV causes an increase in wall stress shear (WSS), and consequent beneficial effects. As a matter of fact, the effect of changes in BV on endothelial function is not yet clear. OBJECTIVES: Aim of the present study was to evaluate in-vivo the effects of the acute reduction in BV on endothelial function, in healthy male subjects. METHODS: Fourteen healthy male blood donors were studied before and 48 hours after blood donation. Blood and plasma viscosity were measured at 37C° with a cone-plate viscometer. Endothelial function was evaluated through flow mediated vasodilation (FMD). RESULTS: Blood viscosity was reduced after blood donation (BV225 (cP) 4.53±0.59 vs.4.18±0.31, p < 0.05). FMD 50 s after cuff deflation was unchanged: 6.23±3.84 vs. 6.62±4.81, p = NS. The vasodilation, however, lasted longer and the area under the curve of FMD was significantly increased: 8.74±8.77 vs.16.14±8.65, p < 0.005. CONCLUSIONS: The present results demonstrate that the acute reduction of BV prolongs vasodilation, without affecting the amount of vasodilatation, possibly as adaptive reaction allowing more time for oxygen release.

No effect on the short-term of a decrease in blood viscosity on insulin resistance.

BACKGROUND: Blood viscosity (BV) might influence glucose delivery to peripheral tissues and play an important role in insulin resistance and diabetes mellitus. However, the exact relationship between BV and insulin resistance is not yet clear. OBJECTIVES: Aim of the present study is to evaluate the effects of the acute reduction in BV on insulin resistance, in healthy male subjects. METHODS: Fifteen healthy male blood donors have been studied before and 48 hours after blood donation. Blood and plasma viscosity have been measured at 37°C with a cone-plate viscometer. Insulin resistance has been evaluated by euglycemic/hyperinsulinemic clamp in eight subjects, and by iHOMA2 Index in further seven subjects. RESULTS: Blood viscosity was markedly reduced after blood donation (BV225 (cP) 4.53 ± 0.59 vs. 4.18 ± 0.31, p < 0.05). Insulin resistance was unchanged: MFFM clamp: 5.6 ± 4.5vs. 4.4 ± 2.2 and iHOMA2 Index 1.2 ± 0.6 vs. 1.2 ± 0.5, before vs. after respectively, p = NS. Blood pressure and lipids were unchanged after blood donation. CONCLUSIONS: The present results demonstrate that acute reduction of BV in healthy male subjects does not change the insulin resistance, measured using both euglycemic/hyperinsulinemic clamp and iHOMA2 Index. Further intervention studies are needed to assess the effect that the reduction in BV can have in subjects with insulin resistance.

Delayed flow-mediated vasodilation and critical coronary stenosis.

Endothelial dysfunction, wall thickening and plaque are progressive manifestations of atherosclerosis. Delayed or absent brachial artery dilation after ischemic stimulus has been associated with severity of extracoronary and coronary atherosclerosis. In the current study, we aimed to verify if delayed or absent dilation associates with critical coronary stenosis. We also evaluated the association between coronary stenosis, carotid artery wall thickness and peripheral artery disease. Endothelial function was investigated by flow-mediated dilation of the brachial artery up to 3 min after ischemia, and patients classified as early, late or no dilators. Coronary angiography was performed through transradial or femoral artery approach. Computerized quantitative angiography was used to obtain percent stenosis of all lesions, while the Gensini score was used to evaluate the severity of coronary atherosclerosis. Seventy-four patients were enrolled. Carotid wall thickness and plaque, and peripheral artery disease were detected by ultrasound. Subjects with critical coronary stenosis showed a higher prevalence of delayed or absent dilation (coronary stenosis ≥70 per cent: late dilators 50 per cent, no dilators 35 per cent; coronary stenosis ≤70 per cent : late dilators 27 per cent, no dilators 6 per cent). The Gensini score was progressively higher in late dilators and no dilators compared with early dilators (early: 4.5±13.5; late 17.5±27.1; no 39.7±55.0; P<0.02). Carotid atherosclerosis and peripheral artery disease were more prevalent in subjects with critical coronary stenosis. Delayed or absent dilation associates with coronary stenosis and different degree of coronary atherosclerosis. The kinetic of arterial dilation seems to be relevant as the magnitude of dilation.

Body fat and blood rheology: Evaluation of the association between different adiposity indices and blood viscosity.

BACKGROUND: In recent years, new measures of body adiposity have been introduced: lipid accumulation product (LAP), body adiposity index (BAI) and body shape index (ABSI). These indices have been demonstrated to better associate with cardiovascular disease than other measures of adiposity. OBJECTIVES: The aim of the present study was to evaluate if LAP or BAI better associate with blood viscosity than other measures of adiposity (body mass index, BMI; waist circumference, WC; waist-to-hip ratio, W/HR; waist-to-height ratio, W/HtR). METHODS: 344 subjects were recruited for the present investigation. Exclusion criteria were: diabetes, elevated triglycerides, smoking and drug use. Blood lipids and glucose were measured by routine methods. Blood and plasma viscosity were measured by a cone-plate viscometer. Adiposity measures were computed as previously described. RESULTS: In simple correlation analyses, blood viscosity (BV) correlated with BMI, BAI, and LAP in males and with LAP in females. Correlations between plasma viscosity and adiposity indices were weak and not statistically significant. Other variables significantly related with BV were: gender, HDL- and LDL-Cholesterol, and triglycerides (p < 0.05). In multiple regression analysis only LAP was associated with BV. CONCLUSIONS: Our data suggest that LAP index is strongly associated to blood viscosity. This result, along with previous evidence, identifies LAP index as a potential cardiovascular risk marker.

Longitudinal Motion Assessment of the Carotid Artery Using Speckle Tracking and Scale-Invariant Feature Transform.

The purpose of this work is to present and validate a novel approach for ultra-sound-based speckle tracking to measure the carotid artery longitudinal displacement, and to assess the apparent sliding between of Intima-Media Complex (IMC) and Adventitia (Ad) layers. This method utilizes feature detectors and descriptors to localize and track keypoints for local motion quantification. The procedure was tested and validated on an in silico dataset and on 18 heathy volunteers and 16 patients. Accuracy measured on in silico data gave a mean ± standard deviation of 23 ± 15 and 19 ± 18 µm for IMC and Ad respectively, and thus smaller than the pixel size (0.0925 mm). Robustness analysis was performed on in vivo images, obtaining a maximum variation coefficient, over 5 repeated measures, of 9.5 and 13.8% for IMC and Ad, respectively. The novel method capability for detecting the relative motion of IMC vs. Ad was compared with visual assessment performed by 2 physicians, leading to a correlation coefficient R of 0.7 in the worst case. (Healthy group scored by rater #1.) In conclusion, our results provide evidence that the novel method is able to accurately and reliably track carotid artery layer motion and that it overcomes limitations currently present in the literature, therefore providing an automatic tool for clinical evaluation of IMC vs. Ad relative displacement.

Wall shear stress is lower in the carotid artery responsible for a unilateral ischemic stroke.

According to the focal nature of atherosclerosis, ischemic stroke is frequently unilateral. Atherosclerotic plaques are favoured by local hemodynamic factors as low wall shear stress and/or elevated circumferential wall tension. Aim of the present study was to investigate the possible association between hemodynamic forces and cerebrovascular disease. Common carotid mean wall shear stress and circumferential wall tension, Peterson's elastic modulus, and blood flow were measured in 25 patients with a recent unilateral large-artery stroke presenting non-stenotic plaques of the carotid arteries (large-artery group), and in 10 patients affected by a recent unilateral cardioembolic stroke without carotid plaques (cardioembolic group). In the large-artery group, atherosclerosis was slightly more evident in the side of cerebral ischemia. All hemodynamic factors were more unfavourable at the affected side in this group (shear stress: 6.2+/-3.0 versus 8.6+/-4.0 dynes/cm2, p<0.0001; wall tension: (7.3+/-1.3)x10(4) versus (6.6+/-1.3)x10(4) dynes/cm, p<0.00001; Peterson's modulus: (16.8+/-11.9)x10(5) versus (12.4+/-5.7)x10(5) dynes/cm2, p=0.06). No difference was detectable in blood flow and in cardioembolic group. The present data demonstrate an unfavourable hemodynamic profile in the common carotid artery supplying the area of a single large-artery stroke and might help to explain the frequent one-sidedness of this disease.

Brachial Low-Flow-Mediated Constriction is Associated with Delayed Brachial Flow-Mediated Dilation.

AIM: Flow-mediated vasodilation (FMD) of the brachial artery measures the ability of the artery to dilate after a forearm ischemia lasting for 5 min. During ischemia, and therefore in conditions of low flow, constriction of the brachial artery (L-FMC) has sometimes been reported. The meaning of L-FMC is still unclear. The aims of our study were to establish the prevalence of subjects with L-FMC, to determine whether the magnitude of L-FMC correlates with magnitude of FMD, and to determine whether L-FMC can be used to predict FMD timing. METHODS: A total of 179 outpatients were studied, and the brachial artery diameter was measured every minute during the 5 min forearm ischemia. Subjects who had at least one measurement showing a constriction of ＞ 1% during ischemia were defined as constrictors. FMD was evaluated at 50 s, 2 min, and 3 min after cuff release. On the basis of time, the subjects in whom maximal dilation had occurred were divided into Early, Late, or No dilators. RESULTS: The brachial artery diameter of 70 subjects (39%) constricted during ischemia. Higher the constriction during ischemia, lower was the dilation after ischemia. Constrictors were more likely to have Late (OR 2.6; ICs 95% 1.19-5.81, p=0.02) or No dilation (OR 4.8; ICs 95% 1.90-12-16, p=0.02) compared with no constrictors. CONCLUSIONS: The present study reveals that almost 40% of the subjects had brachial artery L-FMC and a more pronounced constriction during ischemia correlated with a lower dilation after ischemia. Finally, the prevalence of subjects showing L-FMC was significantly higher among subjects with delayed or no vasodilation, suggesting that L-FMC may be a marker of endothelial dysfunction.

Hemorheological profiles of subjects with prehypertension.

High blood viscosity is associated with increased peripheral resistance and high blood pressure (BP). Prehypertension refers to a systemic BP of 120-139 mm Hg systolic (SBP) and/or 80-89 mm Hg diastolic (DBP). Subjects with prehypertension have an increased risk of overt hypertension and incident cardiovascular disease compared with subjects who have optimal BP. In the present study, we investigated the hemorheological profiles of subjects with prehypertension. A total of 418 apparently healthy subjects were enrolled. BP, plasma lipids and glucose were measured using routine methods. Blood and plasma viscosity were measured using a cone-plate viscometer. The participants were grouped according to BP into the following categories: 'normotensive' (n=100), 'prehypertensive' (n=172), and 'hypertensive' (n=146). The blood viscosity, plasma viscosity and hematocrit of the prehypertensive subjects were higher than those of the normotensive subjects (P<0.01), but they were comparable to those of the hypertensive subjects. In simple correlation analyses, SBP and DBP were directly and significantly correlated with age, body mass index (BMI), blood glucose, hematocrit, plasma viscosity and blood viscosity. In multiple regression analyses, age, fasting blood glucose and plasma viscosity were independently related with SBP, whereas blood viscosity, fasting blood glucose and BMI significantly predicted DBP. These data demonstrate that BP in the range of so-called prehypertension is accompanied by important hemorheological changes, which are similar to those observed in people with overt hypertension. These results could explain the increased cardiovascular risk observed in these subjects as well as their susceptibility to hypertension.

Carotid endothelial shear stress reduction with aging is associated with plaque development in twelve years.

BACKGROUND AND AIMS: Atherosclerosis is associated with clinical, biochemical and haemodynamic risk factors. In a group of subjects studied twelve years apart, we evaluated carotid plaque development in relation to baseline and to changes at follow-up in common carotid haemodynamic profile. METHODS: Forty-eight participants were recruited to a cardiovascular disease prevention programme. Atherosclerotic plaques were evaluated and scored by echography. Endothelial shear stress, circumferential wall tension, and Peterson's elastic modulus as an index of arterial stiffness, were computed by echo-Doppler, along with blood viscosity data. Binary logistic regression analyses were used to test the association among the development of atherosclerosis, cardiovascular risk factors and haemodynamic variations. Analyses were also performed on participants who presented at the follow-up with carotid haemodynamic variations in the left or right common carotid only. RESULTS: Participants (69% male) were aged 64.5 ± 9.7 years at follow-up. Peak and mean endothelial shear stress was significantly lower at follow-up as previously reported; circumferential wall tension and arterial stiffness were significantly higher. Carotid plaque scores increased after 12 years (0.39 ± 0.72 vs. 0.67 ± 0.86, p < 0.01). Of the 96 common carotids analysed, shear stress reduction with aging was an independent predictor of carotid atherosclerosis (B = -0.063; odds ratio = 0.94; p = 0.01). Out of 48 participants, 21 (44%) showed shear stress reduction with aging in only one side of the body and, on this side, the plaque score increased (0.52 ± 0.98 vs. 0.90 ± 0.94, p < 0.05), remaining unchanged in the contralateral carotid tree. CONCLUSIONS: Aging-related shear stress reduction is an independent predictor of atherosclerosis development.

Association between blood viscosity and common carotid artery elasticity.

OBJECTIVE: Elastic properties of the vessel wall are associated with atherosclerosis and major cardiovascular events. Several physiological and pathological conditions can affect arterial elasticity, but few studies have considered the role of hemorheological parameters. The present study aimed to investigate the relationship between hemorheological parameters and vascular stiffness in the carotid artery district. METHODS: One hundred and two individuals were enrolled. Blood and plasma viscosity were measured by a cone-plate viscometer (Wells-Brookfield DV-III, Stoughton, U.S.A.). Echo-Doppler evaluation of carotid arteries was performed in order to calculate elastic indexes (strain, ß-stiffness index and distensibility). The association between hemorheological parameters and carotid elasticity indexes was assessed by simple and multiple regression analyses. RESULTS: In simple correlation analysis, only blood viscosity was directly associated with ß-stiffness index (r = 0.20, p = 0.05) and inversely with strain (r =-0.26, p = 0.01) and distensibility (r =-0.34, p = 0.001). After adjusting for cardiovascular risk factors, blood viscosity, but not plasma viscosity or hematocrit, was independently associated carotid arterial measures, together with age, obesity, hypertension, and dyslipidemia. CONCLUSIONS: The results of the present study demonstrate a strong association between blood viscosity and common carotid elasticity indexes.

Red blood cell distribution width predicts two-hours plasma glucose levels during OGTT.

OBJECTIVE: Red blood cell distribution width (RDW) is a numerical measure, reported as part of a standard complete blood count, usually employed for differential diagnosis of anemic state. Some lines of evidence demonstrate that RDW associates with type 2 diabetes incidence and its complications. To further explore the role of RDW as predictor of abnormal glucose metabolism, we have analyzed the relationship between RDW and 2-hours plasma glucose concentration during an oral glucose tolerance test (OGTT). METHODS: Forty-five outpatients were enrolled for the present study. Participants underwent 75 g OGTT and measurements of hematological parameters. Cardiovascular disease risk factors (blood pressure, blood lipids, cigarette smoking, obesity) were evaluated by routine methods. RESULTS: In simple regression analysis 2-hours post-load glucose was directly associated with age (r = 0.36, p = 0.01), fasting glucose levels (r = 0.40, p = 0.002) and RDW (r = 0.31, p = 0.037). In multiple regression analysis fasting glucose, RDW, triglycerides and age significantly and independently predicted 2-hours plasma glucose (p <  0.01 for all coefficients). CONCLUSION: The present findings demonstrate that RDW associates with plasma glucose concentration after a 75-g oral glucose tolerance test. Our results highlight the role of RDW as predictor of glucose metabolism disturbance.