Elevated blood flow in people with type 1 and type 2 diabetes

AIMS

The study aimed to evaluate blood flow (BF) and microvascular function in the forearm of people with type 1 and type 2 diabetes at rest and after ischemia. Microvascular function plays a crucial role in regulating BF in peripheral tissues based on metabolic demand.

METHODS

People with diabetes and sex-matched healthy controls were recruited. Brachial artery diameter and blood velocity were continuously measured at rest and after ischemia by an automatic tracking system. BF and vascular conductance were then calculated.

RESULTS

Forty-nine people with diabetes and 49 controls were enrolled. BF at rest and after ischemia was significantly higher in people with diabetes than controls: Type 1, 243 ± 116 and 631 ± 233 ml/min; controls, 180 ± 106 and 486 ± 227 ml/min; Type 2, 332 ± 149 and 875 ± 293 ml/min; controls 222 ± 106 and 514 ± 224 ml/min. Vascular conductance was significantly higher in Type 2 than in controls at rest and after ischemia.

CONCLUSIONS

People with diabetes exhibited significantly increased BF, with Type 2 also showing heightened vascular conductance. Activating metabolic pathways triggered by hyperglycemia may lead to distinct vascular redistribution, potentially impairing blood flow over time. These findings of the study underscore the importance of understanding overall vascular dynamics in diabetes and its implications for vascular health.

A Head-to-Head Comparison of Two Algorithms for Adjusting Mealtime Insulin Doses Based on CGM Trend Arrows in Adult Patients with Type 1 Diabetes: Results from an Exploratory Study

BACKGROUND

Continuous glucose monitoring (CGM) users are encouraged to consider trend arrows before injecting a meal bolus. We evaluated the efficacy and safety of two different algorithms for trend-informed bolus adjustments, the Diabetes Research in Children Network/Juvenile Diabetes Research Foundation (DirectNet/JDRF) and the Ziegler algorithm, in type 1 diabetes.

METHODS

We conducted a cross-over study of type 1 diabetes patients using Dexcom G6. Participants were randomly assigned to either the DirectNet/JDRF or the Ziegler algorithm for two weeks. After a 7-day wash-out period with no trend-informed bolus adjustments, they crossed to the alternative algorithm.

RESULTS

Twenty patients, with an average age of 36 ± 10 years, completed this study. Compared to the baseline and the DirectNet/JDRF algorithm, the Ziegler algorithm was associated with a significantly higher time in range (TIR) and lower time above range and mean glucose. A separate analysis of patients on CSII and MDI revealed that the Ziegler algorithm provides better glucose control and variability than DirectNet/JDRF in CSII-treated patients. The two algorithms were equally effective in increasing TIR in MDI-treated patients. No severe hypoglycemic or hyperglycemic episode occurred during the study.

CONCLUSIONS

The Ziegler algorithm is safe and may provide better glucose control and variability than the DirectNet/JDRF over a two-week period, especially in patients treated with CSII.

Continuous Glucose Monitoring-Derived Metrics and Capillary Vessel Density in Subjects with Type 1 Diabetes without Diabetic Retinopathy

Optical coherence tomography angiography (OCTA) is an innovative and reliable technique detecting the early preclinical retinal vascular change in patients with diabetes. We have designed our study to evaluate whether an independent relationship exists between continuous glucose monitoring (CGM)-derived glucose metrics and OCTA parameters in young adult patients with type 1 diabetes without diabetic retinopathy (DR). Inclusion criteria were age ≥ 18 years, diagnosis of type 1 diabetes from ≥ 1 year, stable insulin treatment in the last three months, use of real-time CGM, and CGM wear time ≥ 70%. Each patient underwent dilated slit lamp fundus biomicroscopy to exclude the presence of DR. A skilled operator performed OCTA scans in the morning to avoid possible diurnal variation. CGM-derived glucose metrics from the last 2 weeks were collected through the dedicated software during OCTA. Forty-nine patients with type 1 diabetes (age 29 [18; 39] years, HbA1c 7.7 ± 1.0%) and 34 control subjects participated in the study. Vessel density (VD) of the whole image and parafoveal retina in the superficial (SCP) and deep capillary plexus (DCP) was significantly lower in patients with type 1 diabetes compared to controls. The coefficient of variation of average daily glucose, evaluated by CGM, significantly correlated with foveal and parafoveal VD in SCP and with foveal VD in DCP. High glucose variability might be responsible for the early increase of VD in these areas. Prospective studies may help understand if this pattern precedes DR. The difference we detected between patients with and without diabetes confirms that OCTA is a reliable tool for detecting early retinal abnormalities.

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.

The Effect of Two Different Insulin Formulations on Postprandial Hyperglycemia after High and Low Glycemic-Index Meal in Type 1 Diabetes

Despite multiple pharmacological options, including rapid-acting insulin analogs, postprandial hyperglycemia is still highly prevalent in patients with type 1 and type 2 diabetes. We hypothesize that the new rapid-acting insulin formulation, the so-called faster-acting Aspart, may have a different effect in controlling postprandial hyperglycemic burden according to the quality of the meal compared to the traditional Aspart. Twenty-five patients with type 1 diabetes were consecutively recruited at the diabetes care center of the University Hospital affiliate of the Magna Græcia University of Catanzaro. Each patient performed four meal tests one week apart, two with a predefined high glycemic index (HGI) food and two with a low glycemic index (LGI) food using insulin Aspart once and Faster Aspart the other time. The 0–30 min, 0–60 min, and 0–120 min glucose Area Under the Curve (AUC) of postprandial glycemic excursion, calculated from continuous glucose monitoring data, were significantly lower with Faster Aspart administered before the HGI test meal as compared to Aspart. A significant difference in favor of Faster Aspart was also found when comparing the 0–60 min and 0–120 min AUC after the LGI meal. Faster Aspart may provide better postprandial glucose control than Aspart regardless of the glycemic index of the meal.

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.

Time in Range Does Not Associate With Carotid Artery Wall Thickness and Endothelial Function in Type 1 Diabetes

BACKGROUND

Patients with Type 1 diabetes (T1D) have an increased risk of developing atherosclerosis and complications as myocardial infarction and peripheral artery disease. The thickening of the carotid wall and the brachial artery dysfunction are early and preclinical manifestations of atherosclerosis. The standard marker of care for assessment of glycemic control, glycated hemoglobin, does not associate with early atherosclerosis. We have hypothesized that the emerging metric of glycemic control, as the time spent in the target range (TIR), might be associated with carotid thickening and endothelial dysfunction. According to the hypothesis, we have designed the present research with the aim to evaluate the association between TIR collected in the short and long term and the measures of arterial morphology and function in patients with T1D.

METHODS

In our study, 70 patients and 35 healthy controls underwent ultrasound vascular study to measure carotid artery intima-media thickness (IMT) and brachial artery endothelial function by the flow-mediated dilation (FMD) technique. TIR was collected by a continuous glucose monitoring system for 2 weeks, 3 months, and 6 months before the vascular study.

RESULTS

Patients with T1D showed a significantly higher carotid IMT (mean±SE, 644±19 vs. 568±29 µ; p= 0.04) and a significantly lower FMD (mean±SE, 7.6±0.4 vs. 9.8±0.6%; p=0.01) compared with control subjects. No significant relationship between IMT, FMD, and TIR collected in the short and long term emerged.

CONCLUSIONS

Young patients with T1D have early vascular abnormalities. The percent of TIR does not correlate with preclinical atherosclerosis. This finding underlines the complexity of the interplay between diabetes and atherosclerosis.

Assessment of sleep disturbance in oral lichen planus and validation of PSQI: A case-control multicenter study from the SIPMO (Italian Society of Oral Pathology and Medicine)

BACKGROUND

The wellbeing of oral lichen planus patients (OLPs) may be strongly influenced by a poor quality of sleep (QoS) and psychological impairment. The aims were to analyze the prevalence of sleep disturbance, anxiety, and depression in OLPs and to validate the Pittsburgh Sleep Quality Index (PSQI) in OLPs.

METHODS

Three hundred keratotic OLPs (K-OLPs), 300 with predominant non-keratotic OLP (nK-OLPs), and 300 controls were recruited in 15 Italian universities. The PSQI, Epworth Sleepiness Scale (ESS), Hamilton Rating Scales for Depression and Anxiety (HAM-D and HAM-A), Numeric Rating Scale (NRS), and Total Pain Rating Index (T-PRI) were administered.

RESULTS

Oral lichen planus patients had statistically higher scores than the controls in the majority of the PSQI sub-items (p-values < 0.001**). Moreover, OLPs had higher scores in the HAM-D, HAM-A, NRS, and T-PRI (p-values < 0.001**). No differences in the PSQI sub-items' scores were found between the K-OLPs and nK-OLPs, although nK-OLPs suffered from higher levels of anxiety, depression, and pain (p-values: HAM-A, 0.007**, HAM-D, 0.009**, NRS, <0.001**, T-PRI, <0.001**). The female gender, anxiety, depression (p-value: 0.007**, 0.001**, 0.020*) and the intensity of pain, anxiety, and depression (p-value: 0.006**, <0.001**, 0.014*) were independent predictors of poor sleep (PSQI > 5) in K-OLPs and nK-OLPs, respectively. The PSQI's validation demonstrated good internal consistency and reliability of both the total and subscale of the PSQI.

CONCLUSIONS

The OLPs reported an overall impaired QoS, which seemed to be an independent parameter according to the regression analysis. Hence, clinicians should assess QoS in OLPs and treat sleep disturbances in order to improve OLPs management.

Effect of Extra Virgin Olive Oil and Butter on Endothelial Function in Type 1 Diabetes

Post-prandial hyperglycemia can be relevant in developing early manifestations of atherosclerosis. EVOO (Extra Virgin Olive Oil), rich in saturated fatty acids and commonly used in the Mediterranean diet, seems to control post-prandial hyperglycemia better than butter. Subjects with type 1 diabetes are at higher risk of developing cardiovascular disease and show endothelial dysfunction, an early manifestation of atherosclerosis in the first years of the disease. Our study aims to evaluate whether EVOO and butter influence endothelial function in subjects with type 1 diabetes when added to a single high glycemic index (HGI) meal. In this exploratory cross-over study, 10 subjects with type 1 diabetes and 6 healthy subjects were scheduled to receive two types of HGI meals: one enriched with EVOO and one with butter. Before and after each test meal at different time points, all subjects underwent the evaluation of endothelial function by flow-mediated dilation technique, glucose and lipids measurements, and gastric emptying assessment by ultrasound. Flow-mediated dilation significantly increased after EVOO-enriched meal compared with butter in subjects with type 1 diabetes (two-way-repeated measurements ANOVA, p = 0.007). In patients with type 1 diabetes, the add-on of EVOO to HGI meal improves vascular function compared to butter, which has detrimental effects.

Teleassistance for Patients With Type 1 Diabetes During the COVID-19 Pandemic: Results of a Pilot Study

Background

Telemedicine use in chronic disease management has markedly increased during health emergencies due to COVID-19. Diabetes and technologies supporting diabetes care, including glucose monitoring devices, software analyzing glucose data, and insulin delivering systems, would facilitate remote and structured disease management. Indeed, most of the currently available technologies to store and transfer web-based data to be shared with health care providers.

Objective

During the COVID-19 pandemic, we provided our patients the opportunity to manage their diabetes remotely by implementing technology. Therefore, this study aimed to evaluate the effectiveness of 2 virtual visits on glycemic control parameters among patients with type 1 diabetes (T1D) during the lockdown period.

Methods

This prospective observational study included T1D patients who completed 2 virtual visits during the lockdown period. The glucose outcomes that reflected the benefits of the virtual consultation were time in range (TIR), time above range, time below range, mean daily glucose, glucose management indicator (GMI), and glycemic variability. This metric was generated using specific computer programs that automatically upload data from the devices used to monitor blood or interstitial glucose levels. If needed, we changed the ongoing treatment at the first virtual visit.

Results

Among 209 eligible patients with T1D, 166 completed 2 virtual visits, 35 failed to download glucose data, and 8 declined the visit. Among the patients not included in the study, we observed a significantly lower proportion of continuous glucose monitoring (CGM) and continuous subcutaneous insulin infusion (CSII) users (n=7/43, 16% vs n=155/166, 93.4% and n=9/43, 21% vs n=128/166, 77.1%, respectively; P<.001) compared to patients who completed the study. TIR significantly increased from the first (62%, SD 18%) to the second (65%, SD 16%) virtual visit (P=.02); this increase was more marked among patients using the traditional meter (n=11; baseline TIR=55%, SD 17% and follow-up TIR=66%, SD 13%; P=.01) than among those using CGM, and in those with a baseline GMI of ≥7.5% (n=46; baseline TIR=45%, SD 15% and follow-up TIR=53%, SD 18%; P<.001) than in those with a GMI of <7.5% (n=120; baseline TIR=68%, SD 15% and follow-up TIR=69%, SD 15%; P=.98). The only variable independently associated with TIR was the change of ongoing therapy. The unstandardized beta coefficient (B) and 95% CI were 5 (95% CI 0.7-8.0) (P=.02). The type of glucose monitoring device and insulin delivery systems did not influence glucometric parameters.

Conclusions

These findings indicate that the structured virtual visits help maintain and improve glycemic control in situations where in-person visits are not feasible.

Time spent in target range assessed by self-monitoring blood glucose associates with glycated hemoglobin in insulin treated patients with diabetes

BACKGROUND AND AIMS

Self-monitoring blood glucose (SMBG) remains a widespread tool to monitor blood glucose. The development of diabetes management systems (DMS) allows SMBG to provide additional information as time spent in target range (TIR). This study evaluates the association between HbA1c and TIR, evaluated through DMS, over 2 months, and 2 weeks.

METHODS AND RESULTS

Type 1 (T1D) and Type 2 (T2D) insulin-treated patients with diabetes were enrolled. We used the term PIR (Points in Range) instead of TIR, since SMBG provides point-in-time glucose values rather than a continuous trend over time. PIR was calculated in 2-month and 2-week time ranges before available HbA1c measurement. One-hundred ninety-seven patients with T1D and 36 with T2D were recruited. HbA1c and PIR were inversely associated (2 months: R -0.72, 2 weeks R -0.70; p < 0.0001) in all subjects. The relationship did not change when T1D and T2D patients were analyzed separately. For every 10% change of PIR, there was a change of HbA1c by 0.4%.

CONCLUSIONS

Our study, for the first time, demonstrates a significant correlation between HbA1c and PIR calculated by DMS. DMS offers additional information useful in disease management of patients with T1D and T2D performing SMBG.

Functional and morphological cardiovascular alterations associated with neurofibromatosis 1

Subjects with Neurofibromatosis 1 (NF1) develop vascular complications. The protein product of the gene affected in NF1, neurofibromin, physiologically modulates endothelial function and preserves vascular and myocardial structure. Our study aimed to verify whether subjects with NF1 have early, preclinical abnormalities of carotid artery structure, brachial artery function, and cardiac function. We recruited 22 NF1 subjects without previous cardiovascular events and 22 healthy control subjects. All subjects underwent measurement of carotid artery intima-media thickness (IMT), evaluation of brachial artery endothelial function after ischemia and exercise, and cardiac function. Mean IMT was 543 ± 115 μ in NF1 subjects and 487 ± 70 μ in Controls (p < 0.01). Endothelial function was significantly dumped in NF1 subjects. The dilation after ischemia and exercise was respectively 7.5(± 4.8)% and 6.7(± 3.0)% in NF1 versus 10.5(± 1.2)% and 10.5(± 2.1)% in control subjects (p < 0.02; p < 0.002). Left ventricular systolic function assessed by Global Longitudinal Strain was significantly different between NF1 subjects and Controls: − 19.3(± 1.7)% versus − 21.5(± 2.7)% (p < 0.008). These findings demonstrate that NF1 patients have early morphological and functional abnormalities of peripheral arteries and systolic cardiac impairment and suggest the need for a tight cardiovascular risk evaluation and primary prevention in subjects with NF1.

Clinical use of a 180-day implantable glucose sensor improves glycated haemoglobin and time in range in patients with type 1 diabetes

AIMS

This real-world study evaluated the changes in glycated haemoglobin (HbA1c) and continuous glucose monitoring (CGM) metrics associated with use of the implantable 180-day Eversense CGM System (Eversense) in patients with type 1 diabetes.

MATERIALS AND METHODS

This was a prospective, multicentre, observational study among adult participants aged ≥18 years with type 1 diabetes across seven diabetes-care centres in Italy who had Eversense inserted for the first time. HbA1c was measured at baseline and at 180 days. Changes in time in range [TIR (glucose 70-180 mg/dL)], time above range [TAR (glucose >180 mg/dL)], time below range [TBR (glucose <70 mg/dL)] and glycaemic variability were also assessed. Data were also analysed by previous CGM use and by mode of insulin delivery.

RESULTS

One-hundred patients were enrolled (mean age 36 ± 12 years, mean baseline HbA1c 7.4 ± 0.92% [57 ± 10 mmol/mol]). Fifty-six per cent of patients were users of the continuous subcutaneous insulin infusion pump and 45% were previous users of CGM. HbA1c significantly decreased in patients after 180 days of sensor wear (-0.43% ± 0.69%, 5 ± 8 mmol/mol, P < 0.0001). As expected, CGM-naïve patients achieved the greatest reduction in HbA1c (-0.74% ± 0.48%, 8 ± 5 mmol/mol). TIR significantly increased and TAR and mean daily sensor glucose significantly decreased while TBR did not change after 180 days of sensor wear.

CONCLUSIONS

Real-world clinical use of the Eversense CGM System for 180 days was associated with significant improvements in HbA1c and CGM metrics among adults with type 1 diabetes. The study is registered on clinicaltrials.gov (NCT04160156).

COVID-19 Sepsis and Microcirculation Dysfunction

The spreading of Coronavirus (SARS-CoV-2) pandemic, known as COVID-19, has caused a great number of fatalities all around the World. Up to date (2020 May 6) in Italy we had more than 28,000 deaths, while there were more than 205.000 infected. The majority of patients affected by COVID-19 complained only slight symptoms: fatigue, myalgia or cough, but more than 15% of Chinese patients progressed into severe complications, with acute respiratory distress syndrome (ARDS), needing intensive treatment. We tried to summarize data reported in the last months from several Countries, highlighting that COVID-19 was characterized by cytokine storm (CS) and endothelial dysfunction in severely ill patients, where the progression of the disease was fast and fatal. Endothelial dysfunction was the fundamental mechanism triggering a pro-coagulant state, finally evolving into intravascular disseminated coagulation, causing embolization of several organs and consequent multiorgan failure (MOF). The Italian Society of Clinical Hemorheology and Microcirculation was aimed to highlight the role of microcirculatory dysfunction in the pathogenetic mechanisms of COVID-19 during the spreading of the biggest challenges to the World Health.

The Strategic Alliance between Clinical and Molecular Science in the War against SARS-CoV-2, with the Rapid-Diagnostics Test as an Indispensable Weapon for Front Line Doctors

Our work concerns the actual problem of spread of SARS- CoV-2 outbreak which requires fast and correct as possible answer. In current scenario, the need of rapid answer put away the imperative of proper methodology. We focus on the serogical immunoassay for diagnosis of Covid-19 as an important weapon not only for diagnostic purpose, but also for epidemiologic one. The right equilibrium between high speed, low cost and accuracy is obtained with easy-to-use decentralized point-of-care test as the colloidal gold-based immunochromatographic strip assay which detects IgM and IgG antibodies directed against SARS-CoV-2. As our aim is to evaluate the efficacy of Covid-19 rapid tests and of serological assays in real-life settings, we designed a research protocol aimed to establish how to use correctly these diagnostics, taking into account the different possible clinical and epidemiological scenarios.

Effect of empagliflozin on brachial artery shear stress and endothelial function in subjects with type 2 diabetes: Results from an exploratory study

Empagliflozin reduces the risk of cardiovascular mortality in subjects with type 2 diabetes. We demonstrated that empagliflozin increases blood viscosity and carotid shear stress and decreases carotid wall thickness. Shear stress is the force acting on the endothelial surface and modulates arterial function. The current study evaluates the influence of empagliflozin on brachial artery shear stress and endothelial function compared to incretin-based therapy. The study is a nonrandomized, open, prospective cohort study including 35 subjects with type 2 diabetes administered empagliflozin or incretin-based therapy. Shear stress was calculated with a validated formula, and endothelial function was evaluated using the flow-mediated dilation technique. Both treatments resulted in comparable reductions in blood glucose and glycated haemoglobin. Brachial artery shear stress significantly increased exclusively in the empagliflozin group (61 ± 20 vs 68 ± 25 dynes/cm², p = 0.04), whereas no significant difference was detected in the incretin-based therapy group (60 ± 20 vs 55 ± 12 dynes/cm², p = not significant). Flow-mediated dilation significantly increased in the empagliflozin group (4.8 ± 4.5% vs 8.5 ± 5.6%, p = 0.03). Again, no change was detected in the incretin-based therapy group (5.1 ± 4.5% vs 4.7 ± 4.7%, p = not significant). The present findings demonstrate the beneficial effect of empagliflozin on shear stress and endothelial function in subjects with type 2 diabetes independent of the hypoglycaemic effect.

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.

Hepatic Steatosis Index Is Associated with Type 1 Diabetes Complications

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD) is associated with an increased risk of complications in type 1 diabetes (T1DM) patients. To date, several biochemical indexes of NAFLD have been developed. Among these, hepatic steatosis index (HSI) strongly relates with the results of magnetic resonance.

AIM

The aim of the present study was to evaluate the possible association between HSI and complications in T1DM.

METHODS

Medical records of patients with T1DM were evaluated. Macro- and micro-vascular complications were evaluated by a combination of instrumental (ECG, carotid artery echo-Doppler, fundus examination, vibration threshold at biothesiometry) and laboratory examination. HSI was calculated based on gender, body mass index and transaminases level.

RESULTS

Of the 124 patients evaluated, 71 were free of complications and 53 had at least one complication. The prevalence of diabetes complications was: 27% for retinopathy, 15% for carotid atherosclerosis, 16% for neuropathy. HSI was directly correlated with age, disease duration, triglycerides, total daily insulin and inversely with HDL and eGFR. In logistic regression analysis, HSI was independently associated with diabetic complications.

CONCLUSION

These findings show that HSI is independently associated with the presence of complications in subjects with T1DM. This can be of clinical utility, allowing a better diagnostic classification of the patient and possibly guiding the therapeutic choice.

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.

Empagliflozin influences blood viscosity and wall shear stress in subjects with type 2 diabetes mellitus compared with incretin-based therapy

Background

Cardiovascular protection following empagliflozin therapy is not entirely attributable to the glucose lowering effect. Increased hematocrit might influence the shear stress that is the main force acting on the endothelium, regulating its anti-atherogenic function.

Objective

We designed the study with the aim of investigating the effect of empagliflozin on blood viscosity and shear stress in the carotid arteries. A secondary endpoint was the effect of empagliflozin on carotid artery wall thickness.

Methods

The study was a non-randomized, open, prospective cohort study including 35 type 2 diabetic outpatients who were offered empagliflozin or incretin-based therapy (7 liraglutide, 8 sitagliptin) in combination with insulin and metformin. Blood viscosity, shear stress and carotid wall thickness were measured at baseline and at 1 and 3 months of treatment. Blood viscosity was measured with a viscometer, and shear stress was calculated using a validated formula. Intima-media thickness (IMT) of the carotid artery was detected by ultrasound and was measured with dedicated software.

Results

Blood viscosity (4.87 ± 0.57 vs 5.32 ± 0.66 cP, p < 0.02) and shear stress significantly increased in the Empagliflozin group while no change was detected in the Control group (4.66 ± 0.56 vs 4.98 ± 0.73 cP, p = NS). IMT significantly decreased in the Empagliflozin group after 1 and 3 months (baseline: 831 ± 156, 1-month 793 ± 150, 3-month 766 ± 127 μm; p < 0.0001), while in the liraglutide group, IMT significantly decreased only after 3 months (baseline 879 ± 120; 1-month 861 ± 163; 3-month 802 ± 114 μm; p < 0.001). In the sitagliptin group, IMT remained almost unchanged (baseline 901 ± 135; 1-month 902 ± 129; 3-month 880 ± 140 μm; p = NS).

Conclusions

This study is the first to describe a direct effect of empagliflozin on blood viscosity and wall shear stress. Furthermore, IMT was markedly reduced early on in the Empagliflozin group.

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.

Prevalence and Correlates of Anemia and Uncontrolled Anemia in Chronic Hemodialysis Patients – The Campania Dialysis Registry

Background

This study investigated prevalence and correlates of anemia and uncontrolled anemia in chronic hemodialysis patients.

Methods

A cross-sectional analysis was performed on registry data for 2,746 chronic (<6 months) hemodialysis patients aged 25–84. Data collection included years of dialysis, hours of dialysis/wk, disease causing hemodialysis, body mass index (BMI), erythropoietin (EPO) treatment, hemoglobin, markers of viral hepatitis, serum albumin, calcium, and phosphorus.

Results

Prevalence was 88.7% for anemia (hemoglobin <11 g/100 mL and EPO treatment at any Hb level), 39.4% for uncontrolled anemia (hemoglobin<11 g/100 mL). Gender, years of dialysis, hereditary cystic kidney disease (HCKD), and low BMI (<24 kg/m2) were independent correlates of anemia (P<0.001). Gender, HCKD, low BMI, serum albumin and calcium were independent correlates of uncontrolled anemia (P<0.05). An interaction was found between age (not correlated with anemia and uncontrolled anemia) and the association of gender with uncontrolled anemia (P<0.05). EPO doses were higher in patients with high prevalence of uncontrolled anemia than in patients with low prevalence (i.e., women vs men, other diseases vs HCKD, low vs not-low BMI, P<0.01). Gender, years of dialysis, HCKD, BMI, serum albumin, and calcium were independent correlates of the hemoglobin/EPO dose ratio in patients on EPO treatment (P<0.05).

Conclusion

Anemia and uncontrolled anemia are more frequent in hemodialysis patients with short-term dialysis, diseases other than HCKD, low BMI, and female gender. Gender effect was lower in elderly patients. Uncontrolled anemia was also associated with low serum albumin and calcium, suggesting that these parameters are indices of EPO resistance.

Diabetes Data Management System to Improve Glycemic Control in People With Type 1 Diabetes: Prospective Cohort Study

Background

Smartphone and Web technology can improve the health care process, especially in chronic diseases.

Objective

The aim of this study was to investigate whether the use of blood glucose (BG) data management system, which enables connection to smartphones, the Web, the cloud, and downloading, can improve glycemic control in subjects with type 1 diabetes mellitus (T1DM).

Methods

This study was a prospective, single-arm, cohort feasibility study with 6 months of duration. T1DM subjects enrolled had experience in self-monitoring blood glucose, but were download data naïve. Fasting BG and glycated hemoglobin (HbA_1c) were collected at the enrollment and at follow-up. Subjects were divided into Downloader (DL) and No-downloader (NDL).

Results

A total of 63 subjects were analyzed, of which 30 were classified as DL and 33 as NDL. At the end of the study, DL had significantly lower HbA_1c, mean daily glucose, standard deviation, percentage of BG values above target, and pre- and postprandial (lunch and dinner) values compared with NDL (all P<.05). The percentage of BG values within treatment target was significantly higher in DL compared with NDL (47% [SD 9] vs 37% [SD 13]; P=.001).

Conclusions

The findings suggest that, in T1DM, downloading of BG from data management system, which enables connection to smartphones, the Web, and the cloud, might be a valuable contributor to improved glycemic control.

Evidence for congruent impairment in micro and macrovascular function in type 1 diabetes

Diabetes affects large and small vessels through mechanisms only partially known. In the present study, we evaluated the function of capillaries and large arteries in subjects with type 1 diabetes mellitus (T1DM) to study the effect of chronic hyperglycemia in the absence of other cardiovascular risk factors. Twenty-five subjects with T1DM and 12 healthy age-matched controls were enrolled. Nine patients had mild or moderate retinopathy. Contrast enhanced ultrasound was used to measure perfusion of the deep forearm flexor muscle of the non-dominant arm at rest (baseline) and after an ischemic stimulus (reactive hyperemia). Perfusion was expressed as Video Intensity (VI) in arbitrary unit (a.u.)/mm². The time to reach peak VI after ischemia was also recorded. The function of large arteries was evaluated using flow-mediated vasodilation (FMD). VI was significantly lower in T1DM compared to control subjects both at baseline (0.22±0.16 vs 0.44±0.35 a.u./mm², p<0.05), and after ischemia (0.33±0.24 vs 0.68±0.46 a.u./mm², p<0.05). The time to reach peak VI after ischemia was markedly longer in T1DM (5.6±2.2 vs 4.0±1.7 seconds, p<0.02). These differences were more marked in T1DM subjects with retinopathy. FMD was lower in TIDM patients compared to controls (5.4±6.4 vs 10.7±4.5%, p<0.01). The present findings demonstrate that T1DM patients have defective peripheral skeletal muscle perfusion both at rest and after ischemia compared with control subjects. Low muscle perfusion associates with low FMD of the brachial artery. Furthermore, T1DM subjects with retinopathy have the least muscle perfusion and blunted response to hyperemia compared to T1DM without retinopathy.

Effects on the incidence of cardiovascular events of the addition of pioglitazone versus sulfonylureas in patients with type 2 diabetes inadequately controlled with metformin (TOSCA.IT): a randomised, multicentre trial

BACKGROUND

The best treatment option for patients with type 2 diabetes in whom treatment with metformin alone fails to achieve adequate glycaemic control is debated. We aimed to compare the long-term effects of pioglitazone versus sulfonylureas, given in addition to metformin, on cardiovascular events in patients with type 2 diabetes.

METHODS

TOSCA.IT was a multicentre, randomised, pragmatic clinical trial, in which patients aged 50-75 years with type 2 diabetes inadequately controlled with metformin monotherapy (2-3 g per day) were recruited from 57 diabetes clinics in Italy. Patients were randomly assigned (1:1), by permuted blocks randomisation (block size 10), stratified by site and previous cardiovascular events, to add-on pioglitazone (15-45 mg) or a sulfonylurea (5-15 mg glibenclamide, 2-6 mg glimepiride, or 30-120 mg gliclazide, in accordance with local practice). The trial was unblinded, but event adjudicators were unaware of treatment assignment. The primary outcome, assessed with a Cox proportional-hazards model, was a composite of first occurrence of all-cause death, non-fatal myocardial infarction, non-fatal stroke, or urgent coronary revascularisation, assessed in the modified intention-to-treat population (all randomly assigned participants with baseline data available and without any protocol violations in relation to inclusion or exclusion criteria). This study is registered with ClinicalTrials.gov, number NCT00700856.

FINDINGS

Between Sept 18, 2008, and Jan 15, 2014, 3028 patients were randomly assigned and included in the analyses. 1535 were assigned to pioglitazone and 1493 to sulfonylureas (glibenclamide 24 [2%], glimepiride 723 [48%], gliclazide 745 [50%]). At baseline, 335 (11%) participants had a previous cardiovascular event. The study was stopped early on the basis of a futility analysis after a median follow-up of 57·3 months. The primary outcome occurred in 105 patients (1·5 per 100 person-years) who were given pioglitazone and 108 (1·5 per 100 person-years) who were given sulfonylureas (hazard ratio 0·96, 95% CI 0·74-1·26, p=0·79). Fewer patients had hypoglycaemias in the pioglitazone group than in the sulfonylureas group (148 [10%] vs 508 [34%], p<0·0001). Moderate weight gain (less than 2 kg, on average) occurred in both groups. Rates of heart failure, bladder cancer, and fractures were not significantly different between treatment groups.

INTERPRETATION

In this long-term, pragmatic trial, incidence of cardiovascular events was similar with sulfonylureas (mostly glimepiride and gliclazide) and pioglitazone as add-on treatments to metformin. Both of these widely available and affordable treatments are suitable options with respect to efficacy and adverse events, although pioglitazone was associated with fewer hypoglycaemia events.

FUNDING

Italian Medicines Agency, Diabete Ricerca, and Italian Diabetes Society.

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.

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.

Serum Calcium Increase Correlates With Worsening of Lipid Profile: An Observational Study on a Large Cohort From South Italy

Despite the well-documented role of calcium in cell metabolism, its role in the development of cardiovascular disease is still under heavy debate. Several studies suggest that calcium supplementation might be associated with an increased risk of coronary heart disease, whereas others underline a significant effect on lowering high blood pressure and hyperlipidemia. The purpose of this study was to investigate, in a large nonselected cohort from South Italy, if serum calcium levels correlate with lipid values and can therefore be linked to higher individual cardiovascular risk.Eight-thousand-six-hundred-ten outpatients addressed to the Laboratory of Clinical Biochemistry, University of Magna Græcia, Catanzaro, Italy from January 2012 to December 2013 for routine blood tests, were enrolled in the study. Total HDL-, LDL- and non-HDL colesterol, triglycerides, and calcium were determined with standard methods.We observed a significant association between total cholesterol, LDL-cholesterol, HDL-cholesterol, non-HDL cholesterol, triglycerides, and serum calcium in men and postmenopause women. Interestingly, in premenopause women, we only found a direct correlation between serum calcium, total cholesterol, and HDL-cholesterol. Calcium significantly increased while increasing total cholesterol and triglycerides in men and postmenopause women.Our results confirm that progressive increase of serum calcium level correlates with worsening of lipid profile in our study population. Therefore, we suggest that a greater caution should be used in calcium supplement prescription particularly in men and women undergoing menopause, in which an increase of serum lipids is already known to be associated with a higher cardiovascular risk.

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.

Difference in carotid artery elasticity in subjects with different brachial artery kinetic of vasodilatation

Increased carotid stiffness and impaired brachial artery flow-mediated dilatation (FMD) associate with cardiovascular events. We have previously reported three FMD patterns based on the time of maximal dilatation. The aim of the present study was to verify whether different FMD patterns associate with carotid artery stiffness. In all, 133 subjects were enrolled. All participants underwent complete clinical examination, blood sampling and ultrasound study. FMD was used as a measure of endothelial function. Based on the maximal brachial artery FMD, subjects were divided into Early dilators (peak FMD at 50 s), Late dilators (peak FMD over 50 s) and No dilators. Echo-Doppler evaluation of carotid arteries was performed in order to calculate elastic indexes (strain, β-stiffness index and distensibility). In all, 64 subjects were classified as Early FMD, 36 as Late FMD and 33 as No dilators. Age, gender and cardiovascular risk factors were comparable among three groups. Early FMD had higher values of strain compared with both Late and no Dilators (P<0.001). Furthermore, Early dilators showed a significantly lower stiffness and higher distensibility compared with Late and No dilators. No significant differences between Late FMD and No Dilators were detected. Our results demonstrate that common carotid artery elasticity indexes significantly differ among Early, Late and No dilators. Subjects with delayed or absent brachial artery dilatation have stiffer common carotid arteries compared with subjects with early dilatation. In conclusion, our research suggests that the assessment of the kinetics of FMD in a clinical setting might represent a useful screening tool to improve the cardiovascular risk stratification.

Periodontal Treatment Elevates Carotid Wall Shear Stress in the Medium Term

Periodontal disease is associated with endothelial dysfunction of the brachial artery and hemodynamic alterations of the common carotid artery. Periodontal therapy improves endothelial function. It is not known if it is able also to improve the hemodynamics of the carotid artery. The aim of the current study was to evaluate the efficacy of 2 different periodontal treatments on carotid hemodynamics: scaling and root planing (SRP) alone or together with low-level laser therapy (LLLT). Forty patients were recruited and randomly treated with SRP (n = 20) or SRP + LLLT (n = 20). Periodontal indices (plaque, gingival, and probing depth indices) were measured before and 5 months after treatment. Blood viscosity, common carotid wall shear stress, circumferential wall tension, and Peterson elastic modulus were evaluated before, soon after and 5 months after treatment. It was found that the periodontal indices improved in both groups, but significantly more so for SRP + LLLT than for SRP (decrease in gingival index 69.3% versus 45.4%, respectively, P = 0.04). In the SRP + LLLT group, after a transient reduction by 5% immediately after therapy, shear stress increased by 11% after 5 months. In SRP only group, however, shear stress variations were less marked. No significant changes were found for the other hemodynamic parameters in either of the groups. Periodontal disease treatment by SRP + LLLT can therefore be said to improve common carotid wall shear stress. This suggests a possible mechanism by which the treatment of periodontal disease has beneficial effects on the cardiovascular system.

Blood urea impairs brachial artery flow mediated dilation

AIM

Urea, the main product of protein catabolism, is a biochemical marker of renal function. Though it is known that serum urea impairs vascular health, the relationship between its concentration and vascular reactivity in vivo has not been explored. Our study was undertaken to investigate possible association between serum urea and endothelial function in subjects without chronic kidney disease (CKD).

METHODS

Eighty free-living subjects with serum creatinine ≤1 mg/dL and without CKD were enrolled for the present study. Serum analyses and evaluation of endothelial function were performed in all subjects. Endothelial function was measured using the flow-mediated dilation (FMD) technique. Simple and multiple regression analyses were used to test the association between FMD and considered variables.

RESULTS

In correlation analyses FMD was found directly associated with HDL cholesterol (r=0.21; P=0.05) and eGFR (r=0.25; P=0.02) and inversely associated with age (r=-0.26; P=0.02), serum urea (r=-0.37; P<0.01), serum creatinine (r=-0.31; P<0.01) and brachial artery baseline diameter (r=-0.41; P<0.01). In multiple regression analysis only baseline artery diameter and serum urea predicted FMD; age, gender and cardiovascular risk factors did not relate with FMD.

CONCLUSION

Our study demonstrates the association between serum urea and FMD, suggesting that the accumulation of waste products of protein metabolism may impair vascular health in subjects without CKD.

Management of Type 2 Diabetes Mellitus through Telemedicine

BACKGROUND

Type 2 diabetes mellitus T2DM has a huge and growing burden on public health, whereas new care models are not implemented into clinical practice; in fact the purpose of this study was to test the effectiveness of a program of integrated care for T2DM, compared with ordinary diligence.

METHODS

"Progetto Diabete Calabria" is a new organizational model for the management of patients with diabetes mellitus, based on General Practitioners (GPs) empowerment and the use of a web-based electronic health record, shared in remote consultations among GPs and Hospital Consultants. One-year change in glucose and main cardiovascular risk factors control in 104 patients (Cases) following this integrated care program has been evaluated and compared with that of 208 control patients (Controls) matched for age, gender, and cardiometabolic profile, and followed in an ordinary outpatient medical management by the Consultants only. Both patient groups had Day Hospitals before and after the study period.

RESULTS

The mean number of accesses to the Consultants during the study was 0.6 ± 0.9 for Cases, and 1.3 ± 1.5 for Controls (p<0.0001). At follow-up, glycated hemoglobin (HbA1c) significantly decreased from 58 ± 6 to 54 ± 8 mmol/mol in Cases only (p=0.01); LDL cholesterol decreased in both groups; body mass index decreased in Cases only, from 31.0 ± 4.8 to 30.5 ± 4.6 kg/m(2) (p=0.03).

CONCLUSIONS

The present study demonstrates that a health care program based on GPs empowerment and taking care plus remote consultation with Consultants is at least as effective as standard outpatient management, in order to improve the control of T2DM.

Decreased platelet aggregation by shear stress-stimulated endothelial cells in vitro: description of a method and first results in diabetes

The interaction between platelets and endothelium in vivo is a complex phenomenon. Our aim was to develop an in vitro system that mimics the in vivo environment and investigate platelet function in a common pathological condition. Human umbilical vein endothelial cells were used and platelets from 28 type 2 diabetes patients were studied under shear stress conditions. Mean coefficient of variation of platelet aggregation was 10% in dynamic conditions in the presence of endothelium. Endothelial cells increased the concentration of inductor needed to achieve 50% platelet aggregation to adenosine diphosphate from 2.6 ± 1.3 in static conditions to 3.7 ± 1.3 µM in dynamic conditions. A similar pattern was observed when collagen was used for platelet activation. Incubation of endothelium with a nitric oxide inhibitor abolished this effect, indicating platelet inhibitory effect of endothelial cells is nitric oxide mediated. Platelet reactivity of healthy controls was less influenced by the presence of endothelial cells and displayed reduced basal platelet reactivity compared with platelets from diabetes patients. We show that platelet aggregation in diabetes as commonly reported in vitro may not fully reflect the in vivo pathophysiological process. Future studies are warranted to investigate other pathological conditions and analyse the effects of antiplatelet agents using this system.

Time course analysis of brachial artery flow mediated dilatation in subjects with gingival inflammation

AIM

Several investigations report an inverse association between periodontal disease and endothelial function measured by brachial artery Flow-Mediated-Dilatation (FMD) technique. These studies examined endothelial function by using the traditional approach to FMD calculation, that is from diameters assessed at 60 seconds after deflation. Nevertheless, possible relationship between gingival inflammation and endothelial dysfunction observed over this temporal threshold remains still unexplored. The purpose of our study was to explore the relationship between gingival inflammation and endothelial function, by considering the time course of brachial FMD.

METHODS

Forty-six free-living white subjects, participating in a cardiovascular disease prevention campaign, were enrolled. FMD was measured at 60s and at 2 and 3 min after forearm ischemia. Maximal FMD was calculated (Peak FMD), for each patient. Gingival Index (GI) was evaluated as measure of gingival inflammation.

RESULTS

In univariate analyses, GI was associated with both FMD at 60 sec (r=-0.30, P=0.038) and Peak FMD (r=-0.41, P=0.004). In multiple regression analyses including GI, age, gender, and known risk factors for atherosclerosis, only GI and age were independently and inversely associated with Peak FMD and FMD at 60 s, but this association was stronger with Peak FMD. Moreover, when we divided subjects on the basis of GI value, patients with GI > 1 presented lower Peak FMD and higher prevalence of absent FMD.

CONCLUSION

The present study extends previous observations about the negative effects of periodontal disease on endothelial function, highlighting the importance of the evaluation of time course of vascular reactivity.

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.

Biphasic hemodynamic effects of LDL-apheresis in common carotid artery

OBJECTIVE

Heparin-induced Extracorporeal Low Density Lipoprotein Precipitation (HELP) Apheresis gives beneficial reductions in Low Density Lipoprotein (LDL) cholesterol levels; otherwise, extracorporeal circulation settings might elicit inflammation and platelet aggregation. The net effect of these variations on carotid hemodynamic has not been established. Aim of the present study was to investigate periprocedural variations of common carotid artery wall shear stress, circumferential wall tension, and Peterson's elastic modulus.

METHODS

Measurements were sequentially performed on 22 procedures: immediately before apheresis (T1), within one hour after (T2), after 24 (T3) and 48 hours (T4). In order to confirm acute effects, in additional 30 procedures measurements were performed at T1 and T2.

RESULTS

Mean shear stress was decreased at T2, with an improvement at T4. Mean circumferential wall tension showed an improvement at T4; arterial stiffness showed the same trend, but only close to statistical significance. The following 30 procedures, where measurements were performed at T1 and T2 only, confirmed previous results, showing a deep wall shear stress decrease at T2 (-21%).

CONCLUSION

LDL apheresis seems to have a biphasic effect on common carotid hemodynamics: the acute worsening of shear stress, probably mediated by extracorporeal circulation, was followed by its improvement, possibly driven by LDL cholesterol reduction.

Blood viscosity in subjects with normoglycemia and prediabetes

OBJECTIVE

Blood viscosity (BV) is higher in diabetic patients and might represent a risk factor for the development of insulin resistance and type 2 diabetes. However, data in subjects with normal glucose or prediabetes are missing. In the current study, we evaluated the relationship between BV and blood glucose in subjects with normal glucose or prediabetes.

RESEARCH DESIGN AND METHODS

Enrolled subjects were divided into three groups according to blood glucose: group A (n = 74), blood glucose <90 mg/dL; group B (n = 96), blood glucose ranging from 90 to 99 mg/dL; and group C (n = 94), blood glucose ranging from 100 to 125 mg/dL. BV was measured at 37°C with a cone-plate viscometer at shear rates ranging from 225 to 22.5 s(-1).

RESULTS

Blood pressure, blood lipids, fibrinogen, and plasma viscosity were similar in the three groups. BMI and waist circumference were significantly increased in group C. Hematocrit (P < 0.05) and BV (P between 0.01 and 0.001) were significantly higher in groups B and C compared with group A. Blood glucose was significantly and inversely correlated with HDL cholesterol and directly with BMI, waist, hematocrit (r = 0.134), and BV (from 225 s(-1) to 22.5 s(-1); r ranging from 0.162 to 0.131). BV at shear rate 225 s(-1) was independently associated with blood glucose.

CONCLUSIONS

The current study shows a direct relationship between BV and blood glucose in nondiabetic subjects. It also suggests that, even within glucose values considered completely normal, individuals with higher blood glucose levels have increased BV comparable with that observed in subjects with prediabetes.