Insulin resistance and beta-cell dysfunction in newly diagnosed type 2 diabetes: Expression, aggregation and predominance. Verona Newly Diagnosed Type 2 Diabetes Study 10.

AIMS: We investigated quantitative expression, mutual aggregation and relation with hyperglycemia of insulin resistance (IR) and beta-cell dysfunction (BCD) in newly diagnosed type 2 diabetes. METHODS: We assessed IR with euglycemic hyperinsulinemic clamp and BCD with modelled glucose/C-peptide response to oral glucose in 729 mostly drug-naïve patients. We measured glycated hemoglobin, pre-prandial, post-prandial and meal-related excursion of blood glucose. RESULTS: IR was found in 87.8% [95% confidence intervals 85.4-90.2] and BCD in 90.0% [87.8-92.2] of subjects, ranging from mild to moderate or severe. Approximately 20% of subjects had solely one defect: BCD 10.8% [8.6-13.1] or IR 8.6% [6.6-10.7]. Insulin resistance and BCD aggregated in most subjects (79.1% [76.2-82.1]). We arbitrarily set nine possible combinations of mild, moderate or severe IR and mild, moderate or severe BCD, finding that each had a similar frequency (∼10%). In multiple regression analyses parameters of glucose control were related more strongly with BCD than with IR. CONCLUSIONS: In newly-diagnosed type 2 diabetes, IR and BCD are very common with a wide range of expression but no specific pattern of aggregation. Beta-cell dysfunction is likely to play a greater quantitative role than IR in causing/sustaining hyperglycemia in newly-diagnosed type 2 diabetes.

Glomerular filtration rate decline in T2DM following diagnosis. The Verona newly diagnosed diabetes study-12.

AIMS: Nephropathy is a complication of type 2 diabetes, with increased albuminuria and reduced glomerular filtration rate (GFR) as biomarkers. Rates of progression to end-stage-renal disease are variable among patients. In this study we have examined the GFR decline in newly diagnosed T2DM. METHODS: A cohort of 410 patients with newly diagnosed T2DM and with at least four serum creatinine during the follow-up period were recruited. A linear model was used to calculate the decline in eGFR. A multivariable logistic model was used to identify independent predictors of rapid eGFR decline. RESULTS: Average follow-up was 12.4 years. The eGFR change was -0.80 ±â€¯2.23 ml/min/1.73 m2 per year. Patients were arbitrarily stratified into rapid decliners (≤-3.0 ml/min/1.73 m2 per year), moderate decliners (-2.9/-1 ml/min/1.73 m2 per year) and slow/no decliners (>-1.0 ml/min/1.73 m2 per year). Subjects in the 3 categories were 11.4%, 27.3%, and 61.3%, respectively. Albuminuria was the stronger predictor of rapid eGFR decline. CONCLUSIONS: A rapid decline in eGFR occurs in approximately 1 out of 10 newly diagnosed subjects. This rapid decline can be predicted by widely accessible clinical features, such as albuminuria. Identification of rapid decliners may help to reduce progression toward advanced stages of nephropathy.

Chronic complications in patients with newly diagnosed type 2 diabetes: prevalence and related metabolic and clinical features: the Verona Newly Diagnosed Type 2 Diabetes Study (VNDS) 9.

INTRODUCTION: We explored the presence of chronic complications in subjects with newly diagnosed type 2 diabetes referred to the Verona Diabetes Clinic. Metabolic (insulin secretion and sensitivity) and clinical features associated with complications were also investigated. RESEARCH DESIGN AND METHODS: The comprehensive assessment of microvascular and macrovascular complications included detailed medical history, resting ECG, ultrasonography of carotid and lower limb arteries, quantitative neurological evaluation, cardiovascular autonomic tests, ophthalmoscopy, kidney function tests. Insulin sensitivity and beta-cell function were assessed by state-of-the-art techniques (insulin clamp and mathematical modeling of glucose/C-peptide curves during oral glucose tolerance test). RESULTS: We examined 806 patients (median age years, two-thirds males), of whom prior clinical cardiovascular disease (CVD) was revealed in 11.2% and preclinical CVD in 7.7%. Somatic neuropathy was found in 21.2% and cardiovascular autonomic neuropathy in 18.6%. Retinopathy was observed in 4.9% (background 4.2%, proliferative 0.7%). Chronic kidney disease (estimated glomerular filtration rate <60 mL/min/1.73 m2) was found in 8.8% and excessive albuminuria in 13.2% (microalbuminuria 11.9%, macroalbuminuria 1.3%).Isolated microvascular disease occurred in 30.8%, isolated macrovascular disease in 9.3%, a combination of both in 9.1%, any complication in 49.2% and no complications in 50.8%.Gender, age, body mass index, smoking, hemoglobin A1c and/or hypertension were independently associated with one or more complications. Insulin resistance and beta-cell dysfunction were associated with macrovascular but not microvascular disease. CONCLUSIONS: Despite a generally earlier diagnosis for an increased awareness of the disease, as many as ~50% of patients with newly diagnosed type 2 diabetes had clinical or preclinical manifestations of microvascular and/or macrovascular disease. Insulin resistance might play an independent role in macrovascular disease. TRIAL REGISTRATION NUMBER: NCT01526720.

Sex differences in the association of psychological status with measures of physical activity and sedentary behaviour in adults with type 2 diabetes.

AIM: To assess the association of psychological variables on leisure-time physical activity and sedentary time in men and women with type 2 diabetes mellitus (T2D). METHODS: In this cross-sectional study, we evaluated 163 patients with T2D, consecutively recruited at the Diabetes Centre of the Verona General Hospital. Scores on depression and anxiety symptoms, psychosocial factors (including self-efficacy, perceived interference, perceived severity, social support, misguided support behaviour, spouse's positive behaviour), physical activity and time spent sitting were ascertained using questionnaires responses to the Beck Depression Inventory-II, Beck Anxiety Inventory, Multidimensional Diabetes Questionnaire, International Physical Activity Questionnaire. RESULTS: Physical activity was significantly associated with higher social support in women and with increased self-efficacy in men. Sedentary time was significantly associated with higher perceived interference, anxiety and depressive symptoms, and with reduced diabetes self-efficacy in women, while it was associated solely with anxiety in men. Depressive symptoms and self-efficacy in women and anxiety symptoms in men were independent predictors of sedentary time when entered in a multivariable regression model also including age, BMI, haemoglobin A1c, diabetes duration, perceived interference and self-efficacy as covariates. CONCLUSIONS: Lower self-efficacy and higher symptoms of depression were closely associated with increased sedentary time in women, but not in men, with T2D. It is possible that individualized behavioural interventions designed to reduce depressive symptoms and to improve diabetes self-efficacy would ultimately reduce sedentary behaviours, particularly in women with T2D.

Long-Acting GLP-1 Receptor Agonist Exenatide Influence on the Autonomic Cardiac Sympatho-Vagal Balance.

Long-acting glucagon-like peptide 1 receptor agonists are increasingly used to treat type 2 diabetes. An increase of heart rate (HR) has been observed with their use. To elucidate the role of the cardiac sympatho-vagal balance as a possible mediator of the reported increase in HR, we performed power spectral analysis of HR variability (HRV) in patients receiving exenatide extended-release (ER). Twenty-eight ambulatory patients with type 2 diabetes underwent evaluation at initiation of exenatide-ER and thereafter at 3 and at 6 months. To obtain spectral analyses of HRV, a computerized acquisition of 10 minutes of RR electrocardiogram intervals (mean values of ~700 RR intervals) were recorded both in lying and in standing positions. All patients showed a substantial increase of HR both in lying and in standing positions. Systolic blood pressure, body weight, and glycated hemoglobin A1c significantly decreased both at 3 and 6 months compared with basal levels. The low-frequency/high-frequency ratio varied from 3.05 ± 0.4 to 1.64 ± 0.2 (P < 0.001) after 3 months and to 1.57 ± 0.3 (P < 0.001) after 6 months in a lying position and from 4.56 ± 0.8 to 2.24 ± 0.3 (P < 0.001) after 3 months and to 2.38 ± 0.4 (P < 0.001) after 6 months in a standing position compared with basal values, respectively. HR variations, induced by exenatide-ER treatment, do not appear to be related to sympathetic autonomic tone. Of note, we observed a relative increase of vagal influence on the heart.

The aspartate aminotransferase-to-alanine aminotransferase ratio predicts all-cause and cardiovascular mortality in patients with type 2 diabetes.

An increased aspartate aminotransferase-to-alanine aminotransferase ratio (AAR) has been widely used as a marker of advanced hepatic fibrosis. Increased AAR was also shown to be significantly associated with the risk of developing cardiovascular (CV) disease. The aim of this study was to assess the relationship between the AAR and mortality risk in a well-characterized cohort of patients with type 2 diabetes.A cohort of 2529 type 2 diabetic outpatients was followed-up for 6 years to collect cause-specific mortality. Cox regression analyses were modeled to estimate the independent association between AAR and the risk of all-cause and CV mortality.Over the 6-year follow-up period, 12.1% of patients died, 47.5% of whom from CV causes. An increased AAR, but not its individual components, was significantly associated with an increased risk of all-cause (adjusted-hazard risk 1.83, confidence interval [CI] 95% 1.14-2.93, P = 0.012) and CV (adjusted-hazard risk 2.60, CI 95% 1.38-4.90, P < 0.003) mortality after adjustment for multiple clinical risk factors and potential confounding variables.The AAR was independently associated with an increased risk of both all-cause and CV mortality in patients with type 2 diabetes. These findings suggest that an increased AAR may reflect more systemic derangements that are not simply limited to liver damage. Further studies are needed to elucidate the pathophysiological implications of an increased AAR.

Prevalence of neuropathy in type 2 diabetic patients and its association with other diabetes complications: The Verona Diabetic Foot Screening Program.

AIMS: Somatic neuropathy is a chronic complication of diabetes. The purpose of our study was to determine prevalence and clinical variables associated with somatic neuropathy applying a simple screening method. METHODS: All outpatients with type 2 diabetes attending our diabetic clinic were offered to participate into a diabetic foot screening program, in the period January 2004-December 2012. A total of 3,591 diabetic patients (55.5% men, age 68±10years) underwent detection of somatic neuropathy using the Michigan Neuropathy Screening Instrument in its parts of symptoms (administering a questionnaire) and clinical assessment slightly modified (evaluating foot inspection, vibration sensation by biothesiometer, ankle reflexes). RESULTS: The prevalence of somatic neuropathy was 2.2% in men and 5.5% in women (p<0.001) when assessed by symptom questionnaire, whereas it was 30.5% in men and 30.8% (p=NS) in women when identified by clinical assessment. In subjects with somatic neuropathy macro- and microvascular complications of diabetes were significantly more common. In multivariate logistic regression analyses BMI, HbA1c and ankle/brachial index independently predicted the presence of neuropathy. CONCLUSION: The prevalence of somatic neuropathy in type 2 diabetes is nearly 30% when searched with clinical examination. Poor metabolic control, excess body weight and peripheral arteriopathy are independent markers of somatic neuropathy.

Prevalence of Cardiovascular Autonomic Neuropathy in a Cohort of Patients With Newly Diagnosed Type 2 Diabetes: The Verona Newly Diagnosed Type 2 Diabetes Study (VNDS).

OBJECTIVE: Cardiovascular autonomic diabetic neuropathy (CAN) is a serious complication of diabetes. No reliable data on the prevalence of CAN among patients with newly diagnosed type 2 diabetes are available. Therefore, the aim of this study was to estimate the prevalence of CAN among patients with newly diagnosed type 2 diabetes. RESEARCH DESIGN AND METHODS: A cohort of 557 patients with newly diagnosed type 2 diabetes with cardiovascular autonomic test results available was selected. Early and confirmed neuropathy were assessed using a standardized methodology and their prevalences determined. A multivariate logistic regression analysis was modeled to study the factors associated with CAN. RESULTS: In the entire cohort, the prevalence of confirmed CAN was 1.8%, whereas that of early CAN was 15.3%. Prevalence did not differ between men and women. In the multivariate analyses BMI results were independently and significantly associated with CAN after adjusting for age, sex, hemoglobin A1c, pulse pressure, triglyceride-to-HDL cholesterol ratio, kidney function parameters, and antihypertensive treatment. CONCLUSIONS: CAN could be detected very early in type 2 diabetes. This study may suggest the importance of performing standardized cardiovascular autonomic tests after diagnosis of type 2 diabetes.

Lower levels of 25-hydroxyvitamin D3 are associated with a higher prevalence of microvascular complications in patients with type 2 diabetes.

OBJECTIVE: Low levels of serum 25-hydroxyvitamin D [25(OH)D] are commonly found in type 2 diabetes. We examined whether there is an association between circulating 25(OH)D concentrations and the presence of microvascular complications in people with type 2 diabetes. RESEARCH DESIGN AND METHODS: We studied 715 outpatients with type 2 diabetes who regularly attended our clinic. Participants were evaluated for the presence of microvascular complications (namely retinopathy and/or nephropathy) by clinical evaluation, fundus examination, urine examination and biochemical tests. Serum 25(OH)D levels were also measured for each participant. RESULTS: Hypovitaminosis D (ie, a serum 25(OH)D level <30 ng/mL) was found in 75.4%, while deficiency (ie, a 25(OH)D level <20 ng/mL) was found in 36.6% of these patients. Serum 25(OH)D levels decreased significantly in relation to the severity of either retinopathy or nephropathy or both. In multivariate logistic regression analysis, lower 25(OH)D levels were independently associated with the presence of microvascular complications (considered as a composite end point; OR 0.758; 95% CI 0.607 to 0.947, p=0.015). Notably, this association remained significant even after excluding those with an estimated glomerular filtration rate <60 mL/min/1.73 m(2). CONCLUSIONS: We found an inverse and independent relationship between circulating 25(OH)D levels and the prevalence of microvascular complications in patients with type 2 diabetes. However, vitamin D may be simply a marker and causality cannot be implied from our cross-sectional study. Whether vitamin D supplementation in patients with type 2 diabetes may have beneficial effects on the risk of microvascular complications remains to be investigated.

Glycated haemoglobin is inversely related to serum vitamin D levels in type 2 diabetic patients.

OBJECTIVE: A correlation between glucose control and 25(OH)D metabolism has been suggested by previous studies. However, this correlation has not yet been evaluated considering the impact of chronic complications of type 2 diabetes, especially the presence of nephropathy. Thus, the aim of this study was to determine the correlation between A1C and 25(OH)D in a well characterized cohort of type 2 diabetic patients. RESEARCH DESIGN AND METHODS: We cross-sectionally examined the association between A1C and serum 25(OH) D in 715 type 2 diabetic patients attending our clinic during the years 2011-2012. The average age was 68±12 years (range 26-94 years). The relation between A1C and serum 25(OH)D levels was modelled by multiple linear regression analyses. RESULTS: Serum 25(OH)D levels were inversely associated with A1C levels (r = -0.116, p = .003). This relation maintains its independence in the multivariate analysis after adjusting for age, sex, A1C, BMI, treatment and duration of diabetes and nephropathy. CONCLUSIONS: In type 2 diabetic patients, high A1C levels are associated with low concentrations of serum 25(OH)D independently of duration of diabetes, diabetic treatment and nephropathy. Future studies are needed to clarify the biological relation between glucose control and vitamin D metabolism in type 2 diabetes.

Effects of moderate-intensity exercise training on plasma biomarkers of inflammation and endothelial dysfunction in older patients with type 2 diabetes.

BACKGROUND AND AIMS: Some plasma biomarkers of inflammation and endothelial dysfunction have been recently recognized as important cardiovascular risk factors. Currently, there is little information about the effects of aerobic exercise training on these biomarkers in older adults with type 2 diabetes. We have therefore assessed the effects of a twice-weekly moderate, aerobic exercise programme, without a concomitant weight loss diet, on plasma inflammatory and endothelial dysfunction biomarkers in older type 2 diabetic patients. METHODS AND RESULTS: A group of 16 sedentary, overweight, non-smoking, older patients with type 2 diabetes volunteered to participate in a 6-month, supervised, progressive, aerobic training study, two times per week. Plasma levels of hs-C-reactive protein (hs-CRP), soluble tumour necrosis factor (TNF)-alpha receptors, P-selectin and intercellular adhesion molecule-1 (ICAM-1) were measured before and after physical training. While hs-CRP and soluble TNF-alpha receptors remained essentially unaffected by physical training, plasma concentrations of P-selectin (P<0.001) and ICAM-1 (P<0.01) markedly decreased; physical training also increased HDL cholesterol by 12% (P<0.05) and decreased uric acid levels by approximately 33% (P=0.021). Body weight, waist circumference, blood pressure, haemoglobin A1c, plasma triglyceride and LDL cholesterol concentrations did not change. Interestingly, the exercise-induced changes in ICAM-1 and P-selectin levels remained significant after adjustment for the percent variations of body weight, waist circumference, haemoglobin A1c, HDL cholesterol and uric acid concentrations. CONCLUSIONS: A twice-weekly, 6-month, progressive aerobic-training programme, without a concomitant weight loss diet, is associated with significant decreases in circulating P-selectin and ICAM-1 levels and with a less atherogenic lipid profile in overweight, non-smoking, older type 2 diabetic individuals.

HOMA-estimated insulin resistance is an independent predictor of cardiovascular disease in type 2 diabetic subjects: prospective data from the Verona Diabetes Complications Study.

OBJECTIVE: To evaluate whether homeostasis model assessment-estimated insulin resistance (HOMA-IR) is an independent predictor of cardiovascular disease (CVD) in type 2 diabetes. RESEARCH DESIGN AND METHODS: Conventional CVD risk factors (sex, age, smoking, plasma lipids, blood pressure, and metabolic control) and insulin resistance (estimated by HOMA) were evaluated at baseline in 1,326 patients with type 2 diabetes examined within the Verona Diabetes Complications Study. At baseline and after a mean follow-up of 4.5 years, CVD was assessed by medical history, physical examination, electrocardiography, and echo-Doppler of carotid and lower limb arteries. Death certificates and medical records of subjects who died during the follow-up were carefully scrutinized to identify cardiovascular deaths. In statistical analyses, CVD was an aggregate end point including both fatal and nonfatal coronary, cerebrovascular, and peripheral vascular disease as well as ischemic electrocardiographic abnormalities and vascular lesions identified by echo-Doppler. RESULTS: At baseline, 441 subjects were coded positive for CVD (prevalent cases). Incident cases numbered 126. Multiple logistic regression analyses showed that, along with sex, age, smoking, HDL/total cholesterol ratio, and hypertension, HOMA-IR was an independent predictor of both prevalent and incident CVD. A 1-unit increase in (log)HOMA-IR value was associated with an odds ratio for prevalent CVD at baseline of 1.31 (95% CI 1.10-1.56, P = 0.002) and for incident CVD during follow-up of 1.56 (95% CI 1.14-2.12, P < 0.001). CONCLUSIONS: HOMA-IR is an independent predictor of CVD in type 2 diabetes. The improvement of insulin resistance might have beneficial effects not only on glucose control but also on CVD in patients with type 2 diabetes.