Epidemiology of Diabetes Interventions and Complications (EDIC) Research Group. Effect of intensive diabetes treatment on carotid artery wall thickness in the epidemiology of diabetes interventions and complications. Epidemiology of Diabetes Interventions and Complications (EDIC) Research Group

Adiponectin-leptin ratio as a marker of cardio-metabolic risk in Indian children and youth with type 1 diabetes

OBJECTIVES

Adiponectin/leptin ratio (ALR) is a promising novel marker of cardio-metabolic risk in patients with metabolic syndrome. Our aim was to study the association of adiponectin-leptin ratio with markers of obesity and adiposity and also to assess its usefulness as a marker of increased cardiometabolic risk (CMR) in Indian children and youth with type 1 diabetes mellitus.

METHODS

This observational study included 79 children and youth with type 1 diabetes (T1DM) (10-21 years) having disease duration>6 months. Demographic data and laboratory findings were obtained from patients' records. Patients with ALR<1 were categorised as having increased CMR and those with ALR>1 were categorised as having no CMR.

RESULTS

ALR showed a significant negative correlation with body mass index (BMI), waist and hip circumference and body fat percentage (p<0.05). Body fat percentage was the single most important predictor of ALR. Children and youth with increased CMR had higher weight, BMI, waist and hip circumferences and body fat percentage as compared to those with no CMR (p<0.05). In T1DM children with dyslipidemia, ALR was significantly lower as compared to those without dyslipidemia (p<0.05).

CONCLUSIONS

ALR may be a useful marker for adiposity and increased cardiometabolic risk in Indian children and youth with type 1 diabetes mellitus.

Serum free triiodothyronine is inversely associated with diabetic peripheral neuropathy but not with carotid atherosclerotic lesions in euthyroid patients with type 2 diabetes

BACKGROUND

The associations between serum free triiodothyronine (FT3) and diabetic peripheral neuropatprohy (DPN)/carotid atherosclerotic lesions in euthyroid patients with type 2 diabetes are still unclear. The purpose of our study was to explore the relations of FT3 to DPN and carotid atherosclerotic lesions in Chinese type 2 diabetes inpatients with euthyroid function.

METHODS

2477 euthyroid inpatients with type 2 diabetes were recruited and they were stratified into quartiles by FT3 levels in this cross-sectional study. Peripheral neuropathy was assessed by neurological symptoms and signs as well as nerve conduction velocity tests. Carotid atherosclerotic lesions, including carotid intima-media thickness, plaque and stenosis, were evaluated by Doppler ultrasound.

RESULTS

The prevalence of DPN in type 2 diabetic patients exhibited the significant decrease across the FT3 quartiles (23.5%, 20.9%, 18.8%, and 11.2%, respectively, p < 0.001). Multiple logistical regression analysis also revealed that FT3 quartiles were significantly and inversely associated with DPN. Compared with the subjects in the highest FT3 quartile, the adjusted odds ratios (95% confidence interval) of DPN from the first to third FT3 quartile were successively 2.338 (1.407-3.884), 1.903 (1.134-3.194) and 1.598 (0.960-1.125). The patients with DPN had significantly higher prevalence of carotid atherosclerotic lesions compared with non-DPN patients. However, no statistical association was observed between FT3 quartiles and carotid atherosclerotic lesions after adjusting for confounder factors.

CONCLUSIONS

Lower FT3 within the normal range was independently associated with DPN, but not with carotid atherosclerotic lesions in Chinese euthyroid inpatients with type 2 diabetes.

More Time in Glucose Range During Exercise Days than Sedentary Days in Adults Living with Type 1 Diabetes

Objective: This study analysis was designed to examine the 24-h effects of exercise on glycemic control as measured by continuous glucose monitoring (CGM). Methods: Individuals with type 1 diabetes (ages: 15-68 years; hemoglobin A1c: 7.5% ± 1.5% [mean ± standard deviation (SD)]) were randomly assigned to complete twice-weekly aerobic, high-intensity interval, or resistance-based exercise sessions in addition to their personal exercise sessions for a period of 4 weeks. Exercise was tracked with wearables and glucose concentrations assessed using CGM. An exercise day was defined as a 24-h period after the end of exercise, while a sedentary day was defined as any 24-h period with no recorded exercise ≥10 min long. Sedentary days start at least 24 h after the end of exercise. Results: Mean glucose was lower (150 ± 45 vs. 166 ± 49 mg/dL, P = 0.01), % time in range [70-180 mg/dL] higher (62% ± 23% vs. 56% ± 25%, P = 0.03), % time >180 mg/dL lower (28% ± 23% vs. 37% ± 26%, P = 0.01), and % time <70 mg/dL higher (9.3% ± 11.0% vs. 7.1% ± 9.1%, P = 0.04) on exercise days compared with sedentary days. Glucose variability and % time <54 mg/dL did not differ significantly between exercise and sedentary days. No significant differences in glucose control by exercise type were observed. Conclusion: Participants had lower 24-h mean glucose levels and a greater time in range on exercise days compared with sedentary days, with mode of exercise affecting glycemia similarly. In summary, this study offers data supporting frequency of exercise as a method of facilitating glucose control but does not suggest an effect for mode of exercise.

Prevalence of carotid stenosis following radiotherapy for head and neck cancer: A systematic review and meta-analysis

BACKGROUND

Radiation to the head and neck is a well-established risk factor for the development of carotid artery stenosis. Our objective was to identify the prevalence, incidence, and degree of carotid stenosis in patients with a history of head and neck irradiation.

METHODS

This study was performed according to the PRISMA guidelines. A random effects model meta-analysis was conducted.

RESULTS

Nineteen studies comprising 1479 patients were included. The prevalence of carotid stenosis >50%, >70%, and carotid occlusion was 25% (95% CI: 19%-32%), 12% (95% CI: 7%-17%), and 4% (95% CI: 2%-8%), respectively. The cumulative 12-month incidence of carotid stenosis >50% was 4% (95% CI: 2%-5%), the 24-month was 12% (95% CI: 9%-15%), and the 36-month was 21% (95% CI: 9%-36%).

CONCLUSIONS

The yearly incidence of carotid stenosis >50% increased every year during the first 3 years following radiotherapy. We propose routine yearly Doppler ultrasound screening beginning 1 year after head and neck radiotherapy.

Superior Effects of High-Intensity Interval vs. Moderate-Intensity Continuous Training on Endothelial Function and Cardiorespiratory Fitness in Patients With Type 1 Diabetes: A Randomized Controlled Trial

This study aimed to compare the effect of high-intensity interval training (HIIT) with moderate-intensity continuous training (MCT) on endothelial function, oxidative stress and clinical fitness in patients with type 1 diabetes. Thirty-six type 1 diabetic patients (mean age 23.5 ± 6 years) were randomized into 3 groups: HIIT, MCT, and a non-exercising group (CON). Exercise was performed in a stationary cycle ergometers during 40 min, 3 times/week, for 8 weeks at 50–85% maximal heart rate (HR_max) in HIIT and 50% HR_max in MCT. Endothelial function was measured by flow-mediated dilation (FMD) [endothelium-dependent vasodilation (EDVD)], and smooth-muscle function by nitroglycerin-mediated dilation [endothelium-independent vasodilation (EIVD)]. Peak oxygen consumption (VO_2peak) and oxidative stress markers were determined before and after training. Endothelial dysfunction was defined as an increase < 8% in vascular diameter after cuff release. The trial is registered at ClinicalTrials.gov, identifier: NCT03451201. Twenty-seven patients completed the 8-week protocol, 9 in each group (3 random dropouts per group). Mean baseline EDVD was similar in all groups. After training, mean absolute EDVD response improved from baseline in HIIT: + 5.5 ± 5.4%, (P = 0.0059), but remained unchanged in MCT: 0.2 ± 4.1% (P = 0.8593) and in CON: −2.6 ± 6.4% (P = 0.2635). EDVD increase was greater in HIIT vs. MCT (P = 0.0074) and CON (P = 0.0042) (ANOVA with Bonferroni). Baseline VO_2peak was similar in all groups (P = 0.96). VO_2peak increased 17.6% from baseline after HIIT (P = 0.0001), but only 3% after MCT (P = 0.055); no change was detected in CON (P = 0.63). EIVD was unchanged in all groups (P = 0.18). Glycemic control was similar in all groups. In patients with type 1 diabetes without microvascular complications, 8-week HIIT produced greater improvement in endothelial function and physical fitness than MCT at a similar glycemic control.

The early detection of atherosclerosis in type 1 diabetes: why, how and what to do about it

The major cause of morbidity and often premature mortality in people with type I diabetes (T1D) is cardiovascular disease owing to accelerated atherosclerosis. We review publications relating to the rationale behind, and clinical tests for, detecting and treating early atherosclerosis in people with T1D. Currently available tools for atherosclerosis assessment include risk equations using vascular risk factors, arterial intima-media thickness, the ankle-brachial index, coronary artery calcification and angiography, and for more advanced lesions, intravascular ultrasound and optical coherence tomography. Evolving research tools include risk equations incorporating novel clinical, biochemical and molecular tests; vascular MRI and molecular imaging. As yet there is little information available to quantify early atherosclerosis. With better means to control the vascular risk factors, such as hypertension, dyslipidaemia and glycaemic control, and emerging therapies to control novel risk factors, further epidemiologic and clinical trials are merited to facilitate the translation into clinical practice of robust means to detect, monitor and treat early atherosclerosis in those with T1D.

Substance Use in Adults With Type 1 Diabetes in the T1D Exchange

PURPOSE

The purpose of the study was to evaluate frequency of use and problem use of psychoactive substances in adults with type 1 diabetes (T1D).

RESEARCH DESIGN AND METHODS

Standardized instruments for assessing tobacco, alcohol, and other psychoactive substance use were emailed to 4311 adult participants at 69 T1D Exchange Registry Exchange Registry centers. A total of 936 respondents (61% female, 90% non-Hispanic white, age 38 ± 16 years) completed the survey.

RESULTS

In the sample, 166 (18%) reported past-year use of tobacco and 51 (5%) reported daily use. Past-year alcohol use was reported by 742 (79%) participants, past-month use by 592 (63%), and daily/near-daily use by 87 (9%); 174 (19%) were classified as binge drinkers and 93 (11%) as problem drinkers. Nonprescription use of another psychoactive substance in the past year was reported by 228 (24%), with 167 (18%) indicating they used marijuana, 67 (7%) opioids, 45 (5%) sedatives, and 37 (4%) stimulants. Past-year problem use of these substances was noted in 31 (3%) respondents.

CONCLUSIONS

Adults with T1D in the United States use substances at rates that meet or exceed the general population; problematic use occurs at rates similar to the general population. These data delineate the need to inquire about regular, intermittent, and problematic use of nicotine and other substances in individuals with T1D. A better understanding of the impact of moderate and occasional use of substances on T1D management and clinical outcomes is needed.

Further options for treating lipids in people with diabetes: targeting LDL-cholesterol and beyond

Diabetes is associated with increased cardiovascular disease (CVD) risk. Previous studies with statins have established that a 1 mmol/l reduction in LDL-cholesterol reduces CVD events by 21% over 5 years in people with diabetes. More recently, trials in people with acute coronary syndromes showed that ezetimibe reduced CVD events by 6% at 5 years and achieved a LDL-cholesterol of 1.6 mmol/l with better results in people with Type 2 diabetes. Several novel lipid-lowering therapies have recently been developed. Most data have been accumulated with proprotein convertase subtilisin kexin-9 (PCSK-9) inhibitors, which reduce LDL-cholesterol by 50-55%. A large CVD outcome trial with evolocumab, in which 40% of participants had diabetes, achieved a LDL-cholesterol of 0.8 mmol/l and showed a consistent 20% relative risk reduction within 2 years, including in people with diabetes. Trials to increase HDL-cholesterol using cholesterol ester transfer protein (CETP) inhibitors have generally underwhelmed. Although anacetrapib reduced coronary ischaemic events by 7% in a population with chronic CVD, more expansive CVD endpoints were not improved. The complex nature of CETP inhibitor trial outcomes means that these compounds are not being developed further. Trials targeting inflammation-associated lipids have been generally unsuccessful but recent data on the interleukin-1B receptor antagonist canakinumab have shown a reduction in acute coronary intervention, validating this target although at the cost of increased infections. The ability to achieve low LDL-cholesterol with off-patent medications and the costs of novel therapies will confine the use of novel agents to subgroups of people at highest risk of CVD.

Apolipoprotein-defined lipoprotein subclasses, serum apolipoproteins, and carotid intima-media thickness in T1D

Circulating apolipoprotein-defined lipoprotein subclasses (ADLS) and apolipoproteins predict vascular events in the general and type 2 diabetes populations, but data in T1D are limited. We examined associations of ADLS, serum apolipoproteins, and conventional lipids with carotid intima-media thickness (IMT) measured contemporaneously and 6 years later in 417 T1D participants [men: n = 269, age 42 ± 6 y (mean ± SD); women: n = 148, age 39 ± 8 y] in the Epidemiology of Diabetes Interventions and Complications study, the follow-up of the Diabetes Control and Complications Trial (DCCT). Date were analyzed by multiple linear regression stratified by sex, and adjusted for time-averaged hemoglobin A1C, diabetes duration, hypertension, BMI, albuminuria, DCCT randomization, smoking, statin treatment, and ultrasound devices. In cross-sectional analyses, lipoprotein B (Lp-B), Lp-B:C, Lp-B:E+Lp-B:C:E, Apo-A-II, Apo-B, Apo-C-III-HP (heparin precipitate; i.e., Apo-C-III in Apo-B-containing lipoproteins), and Apo-E were positively associated with common and/or internal carotid IMT in men, but only Apo-C-III (total) was (positively) associated with internal carotid IMT in women. In prospective analyses, Lp-B, Apo-B, and Apo-C-III-HP were positively associated with common and/or internal carotid IMT in men, while Lp-A1:AII and Apo-A1 were inversely associated with internal carotid IMT in women. The only significant prospective association between conventional lipids and IMT was between triacylglycerols and internal carotid IMT in men. ADLS and apolipoprotein concentrations may provide sex-specific biomarkers and suggest mechanisms for IMT in people with T1D.

Effect of Metformin on Vascular Function in Children With Type 1 Diabetes: A 12-Month Randomized Controlled Trial

CONTEXT

Children with type 1 diabetes have vascular dysfunction preceding atherosclerosis. Early interventions are needed to reduce cardiovascular disease.

OBJECTIVE

To evaluate the effect of metformin on vascular function in children with type 1 diabetes.

DESIGN

Twelve-month double-blind, randomized, placebo-controlled trial.

SETTING

Tertiary pediatric diabetes clinic.

PARTICIPANTS

Ninety children (8 to 18 years of age), >50th percentile body mass index (BMI), with type 1 diabetes.

INTERVENTION

Metformin (up to 1 g twice a day) or placebo.

MAIN OUTCOME MEASURE

Vascular function measured by brachial artery ultrasound [flow-mediated dilatation/glyceryl trinitrate-mediated dilatation (GTN)].

RESULTS

Ninety participants were enrolled [41 boys, 13.6 (2.5) years of age, 45 per group], 10 discontinued intervention, and 1 was lost to follow-up. On metformin, GTN improved, independent of glycosylated hemoglobin (HbA1c), by 3.3 percentage units [95% confidence interval (CI) 0.3, 6.3, P = 0.03] and insulin dose reduced by 0.2 U/kg/d (95% CI 0.1, 0.3, P = 0.001) during 12 months, with effects from 3 months. Metformin had a beneficial effect on HbA1c at 3 months (P = 0.001) and difference in adjusted HbA1c between groups during 12 months was 1.0%; 95% CI 0.4, 1.5 (10.9 mmol/mol; 95% CI 4.4, 16.4), P = 0.001. There were no effects on carotid/aortic intima media thickness, BMI, lipids, blood pressure, or other cardiovascular risk factors. Median (95% CI) adherence, evaluated by electronic monitoring, was 75.5% (65.7, 81.5), without group differences. More gastrointestinal side effects were reported on metformin (incidence rate ratio 1.65, 95% CI 1.08, 2.52, P = 0.02), with no difference in hypoglycemia or diabetic ketoacidosis.

CONCLUSIONS

Metformin improved vascular smooth muscle function and HbA1c, and lowered insulin dose in type 1 diabetes children. These benefits and good safety profile warrant further consideration of its use.

Impaired flow-mediated dilation response and carotid intima-media thickness in patients with type 1 diabetes mellitus with a mean disease duration of 4.1 years

OBJECTIVE

This study aimed at assessing the endothelial function in patients with Type 1 diabetes (T1DM) using flow-mediated dilation (FMD) response and carotid artery intima-media thickness (CIMT).

MATERIALS AND METHODS

This study enrolled 32 T1DM patients (mean disease duration 4.1 years) and 28 age-matched controls (CTL Group). Endothelial function and CIMT were assessed with high-resolution ultrasound using standardized offline measurements.

RESULTS

FMD was significantly lower in patients in the T1DM Group (8.9 ± 3.2%) compared with those in the CTL Group (13.3 ± 4.3%; P-value < 0.0001). Similarly, CIMT differed significantly between T1DM patients (0.525 ± 0.03 mm) and controls (0.508 ± 0.03 mm; P-value = 0.041). Even though, the values are within the normal range for age.

CONCLUSIONS

Patients with T1DM have impaired endothelial function characterized by reduced FMD when compared to controls. However, vascular remodeling as seen by increases in CIMT was not found in this study.

Review: Endothelial dysfunction and pre-symptomatic atherosclerosis in type 1 diabetes — pathogenesis and identification

The vascular endothelium offers an attractive model for detecting functional abnormalities prior to structural changes in the vasculature. Demonstration of progression from endothelial dysfunction through to atherosclerosis is required. Measurements of forearm bloodflow, biochemical markers and biophysical assessments of the endothelium have been employed as research tools for investigating pre-symptomatic atherosclerosis.

However, studies examining endothelial function in type 1 diabetes have been sparse and conflicting. Differences in methodology and the study populations were potential confounding factors. Augmented vasodilatory prostanoids compensate for reduced nitric oxide bioavailability in determining endothelial function in type 1 diabetes. Hyperglycaemia appears to be the initiating event in type 1 diabetes which promotes a variety of biochemical events which are pathogenic to the endothelium.

Improved understanding of the endothelium may facilitate the development of novel diagnostic tools and interventions targeting the accelerated atherosclerosis associated with type 1 diabetes.

Optimising glycaemic control — the role of long-acting insulin analogues in basal insulin therapy

Current insulin treatment regimens effectively combat post-prandial hyperglycaemia, but are unable to reinstate normal fasting plasma glucose concentrations. The advent of long-acting soluble insulin analogues, such as insulin glargine and insulin detemir, offers improved control of basal hyperglycaemia without increasing the risk of hypoglycaemia.

Do traditional cardiovascular risk factors solely explain intima-media thickening in youth with type 1 diabetes?

AIMS

The aim of this study was to assess age-specific carotid intima-media thickness (cIMT) in children and adolescents with type 1 diabetes and to investigate associations between cIMT, age, classical cardiovascular disease (CVD) and other risk factors.

METHODS

This study included a cross-sectional analysis of cIMT in 178 patients with type 1 diabetes and 208 healthy controls across age categories. In patients, the impact of gender, socio-economic status, ethnicity, current and historical body mass index, blood pressure, hemoglobin A1c, high-density lipoprotein, and low-density lipoprotein cholesterol on cIMT was studied in a retrospective follow-up cohort study.

RESULTS

Median cIMT was equally greater in patients versus controls across all age categories (P≤0.03). Regression models in patients confirmed a lack of association between cIMT and classical CVD risk factors.

CONCLUSIONS

Children and adolescents with type 1 diabetes showed greater cIMT than controls in all age categories. Increased cIMT did not seem to be consistently associated with classical adult CVD risk factors, adding to the current debate in pediatrics about the impact on classical CVD risk factors to the development of subclinical atherosclerosis in type 1 diabetes. Future studies are warranted to determine if cIMT could assist in predicting macrovascular complications of type 1 diabetes.

Diabetes Dyslipidemia

Diabetes mellitus is associated with a considerably increased risk of premature atherosclerotic cardiovascular disease. Intensive glycemic control has essentially failed to significantly improve cardiovascular outcomes in clinical trials. Dyslipidemia is common in diabetes and there is strong evidence that cholesterol lowering improves cardiovascular outcomes, even in patients with apparently unremarkable lipid profiles. Here, the authors review the pathophysiology and implications of the alterations in lipoproteins observed in both type 1 and type 2 diabetes, the effect of medications commonly used in the management of diabetes on the lipid profile, the evidence for lifestyle and pharmaceutical interventions, and national and international recommendations for the management of dyslipidemia in patients with diabetes.

Lack of evidence for progression of atherosclerosis during puberty in type 1 diabetes

OBJECTIVES

Children with type 1 diabetes have early changes in vascular structure with increased aortic intima-media thickness (aIMT) or carotid IMT (cIMT). aIMT may be an earlier, more sensitive marker; however, longitudinal data in type 1 diabetes are lacking. This study will aim to evaluate changes in vascular structure (aIMT and cIMT) over 2 yr during puberty in children with type 1 diabetes and compare them with those in healthy children.

RESEARCH DESIGN AND METHODS

A total of 110 children (aged 10-18 yr, 55 males) participated in a prospective cohort study, including 77 children with type 1 diabetes and 33 age- and sex-matched healthy children. Ultrasound assessments of aIMT and cIMT; and clinical and biochemical data were collected at baseline and 2 yr later.

RESULTS

Mean and maximal aIMT or cIMT did not worsen over time in children with type 1 diabetes compared with healthy children. Longer duration of diabetes related to an increase in aIMT. Improvement in HDL cholesterol and leptin related to a decrease in aIMT. Higher baseline IMT related to an improvement in IMT in children with type 1 diabetes (mean and maximal aIMT: β = -0.52, p < 0.001; β = -0.49, p = 0.001, and mean and maximal cIMT: β = -0.36, p = 0.003; β = -0.40, p = 0.001), independent of cardiovascular risk factors.

CONCLUSIONS

Aortic and carotid IMT does not deteriorate during puberty in children with type 1 diabetes. This has implications for the design of interventional studies in this important age group.

Plasma Prekallikrein Is Associated With Carotid Intima-Media Thickness in Type 1 Diabetes

The hypothesis that plasma prekallikrein (PK) is a risk factor for the development of vascular complications was assessed in a study using the Diabetes Control and Complications Trial (DCCT)/Epidemiology and Diabetes Interventions and Complications (EDIC) cohort of subjects with type 1 diabetes. The circulating levels of plasma PK activity were measured in the plasma of 636 subjects with type 1 diabetes (EDIC years 3-5). Common and internal carotid intima-media thickness (IMT) were measured by B-mode ultrasonography in EDIC years 1 and 6. Plasma PK levels were positively and significantly associated with BMI, hemoglobin A1c, systolic blood pressure, total cholesterol, LDL cholesterol, and triglycerides but not with age, sex, duration of diabetes, or HDL cholesterol. Univariate and multivariable statistical models after controlling for other risk factors consistently demonstrated a positive association between plasma PK and progression of internal carotid IMT. Multivariate analysis using a general linear model showed plasma PK to be significantly associated with progression of both internal and combined IMT (Wilks Λ P value of 0.005). In addition, the mean internal carotid IMT levels were higher in subjects with plasma PK levels in the highest 10th percentile compared with subjects with plasma PK levels in the lower 10th percentile (P = 0.048). These novel findings implicate plasma PK as a risk factor for vascular disease in type 1 diabetes.

Nuclear magnetic resonance-determined lipoprotein subclasses and carotid intima-media thickness in type 1 diabetes

BACKGROUND

Dyslipidemia has been linked to vascular complications of Type 1 diabetes (T1DM). We investigated the prospective associations of nuclear magnetic resonance-determined lipoprotein subclass profiles (NMR-LSP) and conventional lipid profiles with carotid intima-media thickness (IMT) in T1DM.

METHODS

NMR-LSP and conventional lipids were measured in a subset of Diabetes Control and Complications Trial (DCCT) participants (n = 455) at study entry ('baseline', 1983-89), and were related to carotid IMT determined by ultrasonography during the observational follow-up of the DCCT, the Epidemiology of Diabetes Interventions and Complications (EDIC) study, at EDIC Year 12 (2004-2006). Associations were defined using multiple linear regression stratified by gender, and following adjustment for HbA1c, diabetes duration, body mass index, albuminuria, DCCT randomization group, smoking status, statin use, and ultrasound devices.

RESULTS

In men, significant positive associations were observed between some baseline NMR-subclasses of LDL (total IDL/LDL and large LDL) and common and/or internal carotid IMT, and between conventional total- and LDL-cholesterol and non-HDL-cholesterol and common carotid IMT, at EDIC Year 12; these persisted in adjusted analyses (p < 0.05). Large LDL particles and conventional triglycerides were positively associated with common carotid IMT changes over 12 years (p < 0.05). Inverse associations of mean HDL diameter and large HDL concentrations, and positive associations of small LDL with common and/or internal carotid IMT (all p < 0.05) were found, but did not persist in adjusted analyses. No significant associations were observed in women.

CONCLUSION

NMR-LSP-derived LDL particles, in addition to conventional lipid profiles, may help in identifying men with T1DM at highest risk for vascular disease.

Longitudinal Association Between Endothelial Dysfunction, Inflammation, and Clotting Biomarkers With Subclinical Atherosclerosis in Type 1 Diabetes: An Evaluation of the DCCT/EDIC Cohort

OBJECTIVE

There is considerable interest in identifying biomarkers that predict high risk for the development of macrovascular complications in patients with diabetes. Therefore, the longitudinal association between subclinical atherosclerosis as measured by internal carotid artery intima-media thickness (IMT) and acute-phase reactants, cytokines/adipokines, thrombosis, and adhesion molecules was examined.

RESEARCH DESIGN AND METHODS

Biomarkers were measured at four time points over 20 years in 886 DCCT/EDIC participants with type 1 diabetes. Four composite scores were created by combining z scores generated from within the data set of individual biomarkers: acute-phase reactants (fibrinogen, C-reactive protein), thrombosis (fibrinogen, active and total plasminogen activator inhibitor [PAI]-1), cytokines/adipokines (tumor necrosis factor receptor-1 and -2, active and total PAI-1, IL-6), and endothelial dysfunction (soluble intracellular adhesion molecule-1, soluble vascular cell adhesion molecule-1, and soluble E-selectin). Internal carotid IMT was measured at EDIC years 1, 6, and 12, with elevated IMT defined at each time point as being in the upper quintile of its distribution.

RESULTS

Logistic regression models indicate that while individual biomarkers were not predictive of or associated with subclinical atherosclerosis, composite scores of acute-phase reactants (odds ratio [OR] 2.78 [95% CI 1.42, 5.42]), thrombolytic factors (OR 2.83 [95% CI 1.45, 5.52]), and cytokines/adipokines (OR 2.83 [95% CI 1.48, 5.41]) measured at our final time point EDIC years 8-11 were associated with higher levels of atherosclerosis at EDIC year 12, but findings were not consistent at early time points. The endothelial dysfunction score was not appreciably predictive of or associated with subclinical atherosclerosis at any of the time points measured.

CONCLUSIONS

The pathophysiologic relationship between higher biomarker levels and progression of subclinical atherosclerosis remains unclear.

Long-term insulin glargine therapy in type 2 diabetes mellitus: a focus on cardiovascular outcomes

Cardiovascular disease is the leading cause of mortality in type 2 diabetes mellitus. Hyperinsulinemia is associated with increased cardiovascular risk, but the effects of exogenous insulin on cardiovascular disease progression have been less well studied. Insulin has been shown to have both cardioprotective and atherosclerosis-promoting effects in laboratory animal studies. Long-term clinical trials using insulin to attain improved diabetes control in younger type 1 and type 2 diabetes patients have shown improved cardiovascular outcomes. Shorter trials of intensive diabetes control with high insulin use in higher risk patients with type 2 diabetes have shown either no cardiovascular benefit or increased all cause and cardiovascular mortality. Glargine insulin is a basal insulin analog widely used to treat patients with type 1 and type 2 diabetes. This review focuses on the effects of glargine on cardiovascular outcomes. Glargine lowers triglycerides, leads to a modest weight gain, causes less hypoglycemia when compared with intermediate-acting insulin, and has a neutral effect on blood pressure. The Outcome Reduction With Initial Glargine Intervention (ORIGIN trial), a 6.2 year dedicated cardiovascular outcomes trial of glargine demonstrated no increased cardiovascular risk.

Skin autofluorescence is associated with carotid intima-media thickness, diabetic microangiopathy, and long-lasting metabolic control in type 1 diabetic patients. Results from Poznan Prospective Study

AIMS

Our aim was to assess the association between skin autofluorescence (AF) related to advanced glycation end products (AGEs) accumulation and long-term metabolic control, microvascular complications and carotid intima-media thickness (IMT) in an observational cohort of type 1 diabetes (DM1).

METHODS

The analysis included 77 patients with DM1 (28 women and 49 men) aged 38 (IQR: 34-41), diabetes duration 15 (14-17), participating in Poznan Prospective Study (PoProStu). Skin AF was measured with AGE Reader (DiagnOptics).

RESULTS

We found 50% of any microvascular complication; 37% of retinopathy, 37% of diabetic kidney disease and 22% of distal symmetrical neuropathy. Median carotid IMT was 0.57 (0.52-0.67) mm and skin AF 2.2 (IQR: 1.9-2.6). We found positive correlation between skin AF and patients' age (r=0.31, p=0.006), mean HbA1c from the observation time (r=0.35, p=0.001) and IMT (r=0.39, p<0.001). In multivariate logistic regression presence of microvascular complications was independently associated with skin AF: for retinopathy (OR 3.49; 95% CI: 1.08-11.28, p=0.03), for diabetic kidney disease (OR 3.62; 95% CI: 1.16-11.28, p=0.02), for neuropathy (OR 5.01; 95% CI: 1.21-20.77, p=0.02) and for any microangiopathy (OR 3.13; 95% CI: 1.06-9.18, p=0.03).

CONCLUSION

Skin AF is a reliable marker of past glycemic control of diabetes. Increased accumulation of AGEs is related to the presence of diabetic microangiopathy as well as subclinical macroangiopathy in patients with type 1.

Influence of a family history of type 2 diabetes, demographic and clinical data on carotid intima-media thickness in patients with type 1 diabetes: a cross-sectional study

Background

Intima-media thickness (IMT) of the common carotid artery is a surrogate end point of cardiovascular disease (CVD). Identifying the factors associated with a higher IMT may contribute to the identification of subjects with higher CVD risk. Our objective was to compare the common carotid IMT of type 1 diabetes patients to healthy control subjects. The secondary objective was to determine factors associated with a higher carotid IMT.

Methods

We conducted a cross-sectional study between March 2009 and October 2013, comprising 127 type 1 diabetes patients and 125 control subjects matched by age, gender and body mass index (BMI). Carotid IMT was measured using semi-automated edge detection software.

Results

Type 1 diabetes patients had a higher median IMT compared with control subjects (0.538; IQR: 0.500-0.607 vs 0.513 mm; IQR: 0.481-0.557, respectively p = 0.001). Women with type 1 diabetes had a higher median IMT difference compared to the control group (0.537; IQR: 0.495-0.596 vs 0.502 mm; IQR: 0.472-0.543, respectively p = 0.003) than did men with type 1 diabetes (0.547; IQR: 0.504-0.613 vs 0.528 mm; IQR: 0.492-0.575, respectively p = 0.2). Age and diabetes duration had an additive effect on the IMT of type 1 diabetes patients. Multivariate gamma regression model analysis showed that in type 1 diabetes patients, the IMT was associated with age (Exp (β) = 1.006, p < 0.001), duration of diabetes (Exp (β) = 1.004, p = 0.001), BMI (Exp (β) = 1.005, p = 0.021), family history of type 2 diabetes (Exp (β) = 1.044, p = 0.033), total cholesterol (Exp (β) = 0.999, p = 0.001) and creatinine clearance (Exp (β) = 1.000, p = 0.043).

Conclusions

Patients with type 1 diabetes have increased IMT, a marker of subclinical atherosclerosis. The CVD risk may be similar between men and women with type 1 diabetes, suggesting a loss of gender protection. Also, CVD risk may be higher in those with a family history of type 2 diabetes. Prospective studies are needed to confirm the predictive value of these findings and the causal effect between IMT and CVD in patients with type 1 diabetes.

Plasminogen activator inhibitor-1 (PAI-1) in children and adolescents with type 1 diabetes mellitus: relation to diabetic micro-vascular complications and carotid intima media thickness

BACKGROUND

Plasminogen activator inhibitor-1 (PAI-1) is a fast-acting inhibitor of fibrinolysis that has been linked to increase risk of thrombosis. We determined PAI-1 levels in 80 children and adolescents with type 1 diabetes (T1DM) compared with 40 healthy controls as a potential marker for micro-vascular complications and assessed the relation to carotid intima media thickness (CIMT) as a synergistic risk factor for development of atherosclerosis.

METHODS

Patients were divided into 2 groups according to micro-vascular complications. Hemoglobin A1c (HbA1c), urinary albumin excretion, fasting serum lipid profile and PAI-1 levels were measured. CIMT of the common carotid artery was assessed using high resolution ultrasonography.

RESULTS

PAI-1 levels were significantly elevated in the group with diabetes compared with control group (p<0.001). PAI-1 levels were also increased in patients with micro-vascular complications compared with those without (p<0.001). CIMT was significantly higher in patients, particularly those with micro-vascular complications than patients without complications or controls (p<0.001). Positive correlations were found between PAI-1 levels and random blood glucose, HbA1c, triglycerides, total cholesterol and CIMT (p<0.05).

CONCLUSIONS

Increased plasma PAI-1 may be involved in the state of hypofibrinolysis in patients with T1DM leading to the occurrence of micro-vascular complications and increased risk of atherosclerosis.

The diabetes control and complications trial/epidemiology of diabetes interventions and complications study at 30 years: summary and future directions

OBJECTIVE The Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study continues to address knowledge gaps in our understanding of type 1 diabetes and the effects of intensive therapy on its long-term complications. RESEARCH DESIGN AND METHODS During the DCCT (1982-1993), a controlled clinical trial of 1,441 subjects with type 1 diabetes, and the EDIC (1994-present), an observational study of the DCCT cohort, core data collection has included medical history questionnaires, surveillance health exams, and frequent laboratory and other evaluations for microvascular and macrovascular disease. Numerous collaborations have expanded the outcome data with more detailed investigations of cardiovascular disease, cognitive function, neuropathy, genetics, and potential biological pathways involved in the development of complications. RESULTS The longitudinal follow-up of the DCCT/EDIC cohort provides the opportunity to continue monitoring the durability of intensive treatment as well as to address lingering questions in type 1 diabetes research. Future planned analyses will address the onset and progression of microvascular triopathy, evidence-based screening for retinopathy and nephropathy, effects of glycemic variability and nonglycemic risk factors on outcomes, long-term impact of intensive therapy on cognitive decline, and health economics. Three new proposed investigations include an examination of residual C-peptide secretion and its impact, prevalence of hearing impairment, and evaluation of gastrointestinal dysfunction. CONCLUSIONS With the comprehensive data collection and the remarkable participant retention over 30 years, the DCCT/EDIC continues as an irreplaceable resource for understanding type 1 diabetes and its long-term complications.

Update on cardiovascular outcomes at 30 years of the diabetes control and complications trial/epidemiology of diabetes interventions and complications study

OBJECTIVE To describe the beneficial long-term effects of an average of 6.5 years of intensive diabetes therapy (INT) in type 1 diabetes on measures of atherosclerosis, cardiac structure and function, and clinical cardiovascular events observed in the Diabetes Control and Complications Trial (DCCT) and the Epidemiology of Diabetes Interventions and Complications (EDIC) study. RESEARCH DESIGN AND METHODS The DCCT was a randomized clinical trial of 1,441 participants assigned to receive INT or conventional therapy (CON). It was conducted between 1983-1993 with an average follow-up of 6.5 years. EDIC (1994-present) is an observational follow-up of the DCCT cohort. Cardiovascular events have been recorded throughout. During EDIC common carotid intima-media thickness (IMT) was measured with ultrasound, coronary artery calcification with computed tomography, and cardiac structure and function with cardiac magnetic resonance imaging. RESULTS DCCT INT and lower levels of HbA1c during DCCT/EDIC were associated with thinner carotid IMT, less coronary calcification, and a lower incidence of clinical cardiovascular events including myocardial infarction, stroke, and cardiac death. While there were no significant differences in cardiac structure and function between the former INT and CON groups, they were significantly associated with higher HbA1c during DCCT/EDIC. CONCLUSIONS DCCT INT and the attendant 6.5 years of lower HbA1c had long-term salutary effects on the development and progression of atherosclerosis and cardiovascular disease during the subsequent follow-up during EDIC.

The relationship between early atherosclerosis and endothelial dysfunction in type 1 diabetic patients as evidenced by measurement of carotid intima-media thickness and soluble CD146 levels: a cross sectional study

Background

Detection of early vascular changes prior to clinical manifestations of atherosclerosis, such as increased arterial carotid intima-media thickness (CIMT) and impaired endothelial function is of paramount importance for early identification of subjects at increased risk of accelerated atherosclerosis. The present study was designed to evaluate the relationship between early atherosclerosis and endothelial dysfunction in type 1 diabetic patients based on measurements of CIMT and soluble CD146 (sCD146) levels.

Methods

Thirty-seven patients with type 1 diabetes, 14 males (37.8%) and 23 females (62.2%), of mean (SD) age 26.2 (4.1) years admitted to the outpatient diabetes clinic at Okmeydani Training and Research Hospital, Istanbul, between January 2008 and December 2012, and 37 healthy controls, 16 males (43.2%) and 21 females (56.8%), of mean (SD) age 25.8 (3.1) years, selected from relatives of patients, were included. Anthropometric measures; fasting plasma glucose; and serum HbA1c, total cholesterol, HDL-cholesterol, LDL-cholesterol, triglyceride and creatinine concentrations were compared, as were CIMT and serum sCD146.

Results

Mean (SD) sCD146 levels were significantly higher in patients than in controls (314.6 (141.9) ng/ml vs. 207.8 (34.5) ng/ml, p = 0.001), but mean (SD) CIMT did not differ (0.5 (0.1) mm vs. 0.4 (0.1) mm). ROC curves for sCD146 significantly differed in differentiating type 1 diabetics from healthy controls (p = 0.0047) with a significantly higher percentage of patients than controls having sCD146 levels >260 ng/ml (21/37 (56.8%) vs. 2/37 (5.4%), p = 0.00011).

Conclusion

Our findings emphasize that sCD146 levels may be a more sensitive marker than CIMT for earlier identification of type 1 diabetic patients at high risk for atherosclerosis.

Oxidized LDL and AGE-LDL in circulating immune complexes strongly predict progression of carotid artery IMT in type 1 diabetes

OBJECTIVE

Over 90% of modified LDL in circulation is associated to specific antibodies circulating as part of immune complexes (IC); however, few studies have examined their relationship with cardiovascular disease.

METHODS

We report the relationship between circulating concentrations of IC of oxidized LDL (oxLDL-IC), malondialdehyde-LDL (MDA-LDL-IC) and advanced glycation end products-LDL (AGE-LDL-IC) and progression of atherosclerosis over a 12 year period in 467 individuals with type 1 diabetes who participated in the Diabetes Control and Complications Trial (DCCT) and the Epidemiology of Diabetes Interventions and Complications (EDIC) study. OxLDL-IC, AGE-LDL-IC and MDA-LDL-IC levels were measured at DCCT closeout. Internal carotid intima-medial thickness (IMT) was measured at EDIC follow-up years 1, 6 and 12.

RESULTS

OxLDL-IC, AGE-LDL-IC and MDA-LDL-IC levels were significantly correlated with age, lipid levels, blood pressure levels and albumin excretion rates. Levels of oxLDL, AGE-LDL and MDA-LDL in isolated LDL-IC were highly inter-correlated (r = 0.66-0.84, P < 0.0001). After adjusting for cardiovascular risk factors individuals in the upper quartile of oxLDL-IC had a 2.98-fold increased odds (CI: 1.34, 6.62) of having IMT ≥ 1.00 mm and had a 5.13-fold increased odds (CI: 1.98, 13.3) of having significant IMT progression, relative to those in the lowest quartile. Parallel odds ratios for AGE-LDL-IC were 2.95 (CI: 1.37, 6.34) and 3.50 (CI: 1.38, 8.86), while results for MDA-LDL-IC were 1.76 (0.87, 3.56) and 2.86 (1.20, 6.81).

CONCLUSION

Our study indicates that high levels of oxLDL-IC and AGE-LDL-IC are important predictors of carotid intima-medial thickening in patients with type 1 diabetes.

Low-grade albuminuria is associated with early but not late carotid atherosclerotic lesions in community-based patients with type 2 diabetes

Background

Low-grade albuminuria is associated with cardiovascular risk factors and mortality. Our aim was to investigate the association between low-grade albuminuria and carotid atherosclerotic lesions in community-based patients with type 2 diabetes.

Methods

A cross-sectional study was performed in 475 community-based patients with type 2 diabetes (190 males and 285 females) with normal urinary albumin-to-creatinine ratios (UACR) (< 3.5 mg/mmol) from Shanghai, China. The subjects were stratified into tertiles based on UACR levels (the lowest tertile was UACR ≤ 1.19 mg/mmol, and the highest tertile was UACR ≥ 2 mg/mmol). Carotid intima-media thickness (CIMT), carotid atherosclerotic plaque formation and stenosis were assessed and compared among the three groups based on ultrasonography. The urinary albumin excretion rate was determined as the mean of the values obtained from three separate early morning urine samples.

Results

Compared with the subjects with UACR in the lowest tertile, the subjects with UACR in the middle and highest tertiles had greater CIMT values (0.88 ± 0.35 mm, 0.99 ± 0.43 mm and 1.04 ± 0.35 mm, respectively; all p < 0.05) and a higher prevalence of carotid atherosclerotic plaques (25.3%, 39.0% and 46.2%, respectively; all p < 0.05) after adjusting for sex and age. Fully adjusted multiple linear regression and logistic regression analyses revealed that UACR tertiles were significantly associated with elevated CIMT (p = 0.007) and that, compared with the subjects in the first tertile of UACR, those in the second and third tertiles had 1.878- and 2.028-fold risk of carotid plaques, respectively. However, there was no statistical association between UACR tertile and the prevalence of carotid stenosis.

Conclusions

Higher UACR within the normal range was independently associated with early but not late carotid atherosclerotic lesions in community-based patients with type 2 diabetes. Low-grade albuminuria contributes to the risk of carotid atherosclerosis and may be used as an early marker for the detection of atherosclerosis in patients with type 2 diabetes.

Clinical determinants of carotid intima-media thickness in patients with diabetes mellitus type 2

BACKGROUND AND PURPOSE

Early atherosclerotic changes in carotid arteries can be detected using ultrasound examination. The aim of this study was to assess correlations between intima-media thickness (IMT) and gender, age and clinical features of diabetes mellitus (DM).

MATERIAL AND METHODS

The study group consisted of 73 patients with type 2 DM (mean age: 63.6 ± 7.5 years), and 74 controls without DM (mean age 62.2 ± 7.5 years). Analysed clinical features of diabetes included disease duration, anti-diabetic treatment, glycaemic control (HbA1c level), presence of metabolic syndrome, and complications of macro- and microangiopathy. IMT was measured using ultrasonography in the carotid arteries (common - CCA, bifurcation, internal - ICA) bilaterally.

RESULTS

Mean and maximum IMT in the CCA was greater in diabetic patients than in controls. Age and male sex, but not vascular risk factors, were independent predictors of increased IMT in all segments. Macroangiopathy correlated with IMT within both CCA in univariate analysis. After adjusting for age and gender, this relationship remained significant in the right CCA in middle-aged patients (59-67 years; p = 0.01 for mean IMT, p = 0.02 for maximum IMT). In patients without metabolic syndrome, IMT in the right CCA bifurcation correlated with HbA1c level (p = 0.05). Patients treated simultaneously with insulin and oral antidiabetic drugs had smaller IMT in the right ICA than those treated with insulin only (0.471 ± 0.105 vs. 0.678 ± 0.209 mm; p = 0.04).

CONCLUSIONS

In diabetic patients, ultrasound IMT measurement can be used to assess the cardiovascular risk and to determine indications for intensified anti-diabetic treatment. IMT is a sensitive marker of early carotid atherosclerosis, particularly on the right side.

Demographic and health factors associated with enrollment in posttrial studies: the Women's Health Initiative Hormone Therapy Trials

BACKGROUND

After clinical trials end, continued follow-up of the assembled cohort often is desirable for additional research. Factors influencing participants' decisions to consent to additional follow-up and how these shape posttrial cohorts have not been broadly studied.

PURPOSE

We examined how two re-enrollment campaigns and the passage of time altered features of the posttrial cohorts compared with the original Women's Health Initiative (WHI) Hormone Therapy clinical trials.

METHODS

We examined associations that markers of sociodemography, health, lifestyle, and on-trial experiences had with re-enrollment and contrasted the characteristics of successive posttrial cohorts with those of the original enrollees.

RESULTS

The posttrial enrollment campaigns re-enrolled 81.1% and 82.5% of available women, respectively. Women who re-enrolled tended to have better health characteristics than those not re-enrolled. Compared to women of comparable age in the original cohort, women retained for the second posttrial follow-up less often had a history of cardiovascular disease (odds ratio (OR) = 0.36), hypertension (OR = 0.57), diabetes (OR = 0.59), or measured cognitive deficit (OR = 0.40). These women more often had graduated from high school (OR = 1.72) and had participated in other WHI trials (OR = 1.76).

LIMITATIONS

We have examined experience with creating follow-up cohorts from participants in a single study. Thus, our findings may not apply to other cohorts and protocols.

CONCLUSIONS

Posttrial enrollment in follow-up studies can be successful; however, the characteristics of the resulting cohort may differ substantially from the originally assembled group of trial participants. Collection during the original trial of potential predictors of differential re-enrollment may strengthen interpretation of findings.

Reduction in carotid intima-media thickness after pancreatic islet transplantation in patients with type 1 diabetes

OBJECTIVE

Determine the impact of islet transplantation on carotid intima-media thickness (CIMT), a marker for atherosclerosis, in type 1 diabetes without kidney disease.

RESEARCH DESIGN AND METHODS

Consecutive case series of 15 adults (mean age [SD], 49 years [10 years]; 87% female) with type 1 diabetes for ≥5 years (mean duration [SD], 30 years [12 years]; mean HbA(1c) [SD], 7.2% [0.9%]), without kidney disease, presenting with severe hypoglycemic unawareness to undergo allogeneic pancreatic islet transplant(s) (one to three each) in a phase 1/2 and 3 clinical trial. Current follow-up ranges from 1 to 5 years (2005-2011). CIMT of the common and internal carotid arteries was measured before and every 12-16 months after the first transplant (two to six CIMTs each) by one ultrasonographer and one blinded reader. CIMT was analyzed as change from baseline to 12- and 50-month follow-up; a combined CIMT score was calculated as the sum of the standardized IMT scores (SD units [SDs]) of both arteries.

RESULTS

All patients achieved insulin independence after one to three transplants. CIMT decreased at 12 months (n = 15) for the common carotid (-0.058 mm; P = 0.006) and combined score (-1.28 SDs; P = 0.004). In those with 50-month follow-up (n = 7), the decrease in the combined score continued from 12 (-1.59 SDs; P = 0.04) to 50 months (-0.77 SDs; P = 0.04). During follow-up, the decreasing slope of change in CIMT was associated with decreasing slopes of change in HbA(1c), lipoproteins, and cardiovascular/inflammatory markers.

CONCLUSIONS

Islet transplantation may ameliorate diabetes-related atherosclerosis through improved glycemic control consequent to restoring endogenous insulin secretion, and optimal lipid management posttransplant also contributes.

The effect of excess weight gain with intensive diabetes mellitus treatment on cardiovascular disease risk factors and atherosclerosis in type 1 diabetes mellitus: results from the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications Study (DCCT/EDIC) study

BACKGROUND

Intensive diabetes mellitus therapy of type 1 diabetes mellitus reduces diabetes mellitus complications but can be associated with excess weight gain, central obesity, and dyslipidemia. The purpose of this study was to determine whether excessive weight gain with diabetes mellitus therapy of type 1 diabetes mellitus is prospectively associated with atherosclerotic disease.

METHODS AND RESULTS

Subjects with type 1 diabetes mellitus (97% white, 45% female, mean age 35 years) randomly assigned to intensive or conventional diabetes mellitus treatment during the Diabetes Control and Complications Trial (DCCT) underwent intima-media thickness (n = 1015) and coronary artery calcium score (n = 925) measurements during follow-up in the Epidemiology of Diabetes Interventions and Complications (EDIC) Study. Intensive treatment subjects were classified by quartile of body mass index change during the DCCT. Excess gainers (4th quartile, including conventional treatment subjects meeting this threshold) maintained greater body mass index and waist circumference, needed more insulin, had greater intima-media thickness (+5%, P < 0.001 EDIC year 1, P = 0.003 EDIC year 6), and trended toward greater coronary artery calcium scores (odds ratio, 1.55; confidence interval, 0.97 to 2.49; P = 0.07) than minimal gainers. DCCT subjects meeting metabolic syndrome criteria for waist circumference and blood pressure had greater intima-media thickness in both EDIC years (P = 0.02 to < 0.001); those meeting high-density lipoprotein criteria had greater coronary artery calcium scores (odds ratio, 1.6; confidence interval, 1.1 to 2.4; P = 0.01) during follow-up. Increasing frequency of a family history of diabetes mellitus, hypertension, and hyperlipidemia was associated with greater intima-media thickness with intensive but not conventional treatment.

CONCLUSIONS

Excess weight gain in DCCT is associated with sustained increases in central obesity, insulin resistance, dyslipidemia and blood pressure, as well as more extensive atherosclerosis during EDIC.

CLINICAL TRIAL REGISTRATION

URL for DCCT: http://clinicaltrials.gov; Unique identifier: NCT00360815. URL for EDIC: http://clinicaltrials.gov; Unique identifier: NCT00360893.

Early signs of atherosclerosis are associated with insulin resistance in non-obese adolescent and young adults with type 1 diabetes

Background

Patients with type 1 diabetes have a substantial risk of developing cardiovascular complications early in life. We aimed to explore the role of insulin sensitivity (S_i) as an early factor of atherosclerosis in young type 1 diabetes vs. non-diabetic subjects.

Methods

Forty adolescent and young adult individuals (20 type 1 diabetics and 20 non-diabetics), age 14–20 years, without characteristics of the metabolic syndrome, participated in this cross-sectional study. After an overnight fast, S_i was measured by hyperinsulinemic euglycemic clamp (40 mU/m²) and calculated by glucose infusion rate (GIR). Carotid intima-media thickness (cIMT) was measured in the common carotid artery with high-resolution ultrasonography. Risk factors of atherosclerosis (Body mass index [BMI], waist circumference, systolic blood pressure [sBP], triglycerides, low HDL-cholesterol and HbA_1c) were also investigated.

Results

cIMT was increased (0.52 ± 0.1 vs. 0.47 ± 0.1 mm, P < 0.01), whereas GIR was decreased (5.0 ± 2.1 vs. 7.1 ± 2.2 mg/kg/min, P < 0.01) in type 1 diabetics vs. non-diabetics. The differences in cIMT were negatively associated with S_i (r = −0.4, P < 0.01) and positively associated with waist circumference (r = 0.34, P = 0.03), with no such associations between BMI (r = 0.15, P = 0.32), sBP (r = 0.09, P = 0.58), triglycerides (r = 0.07, P = 0.66), HDL-cholesterol (r = 0.10, P = 0.55) and HbA_1c (r = 0.24, P = 0.13). In a multivariate regression model, between cIMT (dependent) and group (explanatory), only adjustment for S_i affected the significance (ß = 0.08, P = 0.11) vs. (ß = 0.07, P < 0.01) for the whole model. No interaction between cIMT, groups and S_i was observed.

Conclusions

cIMT is increased and associated with insulin resistance in adolescent, non-obese type 1 diabetic subjects. Although, no conclusions toward a causal relationship can be drawn from current findings, insulin resistance emerges as an important factor reflecting early signs of atherosclerosis in this small cohort.

Relation between carotid intima-media thickness and left ventricular mass in type 1 diabetes mellitus (from the Epidemiology of Diabetes Interventions and Complications [EDIC] Study)

Type 1 diabetes mellitus (DM) is associated with early atherosclerosis and increased cardiovascular mortality. The relation between carotid intima-media thickness (cIMT), a marker of subclinical atherosclerosis, and left ventricular (LV) mass, an independent predictor of cardiovascular morbidity, has not been previously studied in type 1 DM. The Epidemiology of Diabetes Interventions and Complications (EDIC) study is a multicenter observational study designed to follow up the Diabetes Control and Complications Trial (DCCT) cohort. LV mass was measured with cardiac magnetic resonance imaging at EDIC year 15 and common cIMT was assessed using B-mode ultrasound at EDIC year 12. Multivariable linear regression models were used to assess the relation between cIMT at year 12 and LV mass at year 15. In total 889 participants had cardiac magnetic resonance imaging and cIMT measurements available for these analyses. At EDIC year 15, mean age of the participants was 49 ± 7 years, mean DM duration was 28 ± 5 years, and 52% were men. Spearman correlation coefficient (r) between LV mass and cIMT was 0.33 (p <0.0001). After adjusting for basic covariates (machine, reader, age, and gender), a significant association between LV mass and cIMT (estimate 2.0 g/m(2) per 0.1-mm cIMT increment, p <0.0001) was observed. This association was decreased by the addition of systolic blood pressure, in particular 1.15 g/m(2) per 0.1-mm cIMT increment (p <0.0001), and to a lesser extent other cardiovascular disease risk factors. Furthermore, the relation observed between LV mass and cIMT was stronger in patients with shorter duration of DM. In conclusion, cIMT was an independent predictor of larger LV mass in a well-characterized population with type 1 DM.

The fats of life in diabetes

Dyslipidaemia is a feature of diabetes and a risk factor for future cardiovascular disease (CVD) though the exact relationships for lipid fractions differ between type 1 and type 2 diabetes. CVD risk equivalence is a well established concept for easy prioritisation of treatment of patients with diabetes as a group but masks a wide range of CVD risk within the group depending on type of diabetes, its duration, the extent of microvascular disease and presence of other risk factors. The first line treatment for CVD risk in diabetes is the use of statins though reduction in non-high-density lipoprotein cholesterol may be a better indicator of efficacy of treatment than low-density lipoprotein cholesterol. The status of all second line therapies for dyslipidaemia in diabetes is unclear as though fibrates and niacin have monotherapy evidence, in general CVD trials to date do not show clear benefits of combination therapy. Multiple novel medications for dyslipidaemia are in development but all require specific investigations in patients with diabetes and also endpoint trials before they can be accepted into general use.

Carotid intima-media thickness and arterial stiffness in type 1 diabetic patients with and without microangiopathy

INTRODUCTION

The aim of the study was to assess carotid intima-media thickness (CIMT) as a subclinical marker of atherosclerosis and arterial stiffness in type 1 diabetic patients in relation to microangiopathy.

MATERIAL AND METHODS

We included 87 type 1 diabetic patients (44 women, 43 men), median age 34 years (interquartile range [IQR] 29-43), median disease duration 10 years (IQR: 9-14), mean ± standard deviation (SD) glycated haemoglobin (HbA(1c)) 8.4 ±1.4%. Fifty patients had at least one microangiopathic complication. Intima-media thickness (IMT) of the common carotid artery was measured using high resolution ultrasonography. Arterial stiffness was assessed using digital volume pulse analysis and tonometric measurement of wave reflection and central haemodynamics.

RESULTS

SUBJECTS WITH MICROANGIOPATHY COMPARED WITH THOSE WITHOUT HAD HIGHER VALUES OF CIMT (MEDIAN [IQR]: 0.53 mm [0.45-0.60 mm] vs 0.47 mm [0.34-0.52 mm], p = 0.002), higher central augmentation index (CAI(x)) (mean ± SD: 120.2 ±19.4% vs. 110.5 ±17.1%, p = 0.016) and higher peripheral augmentation index (PAI(x)) (65.7 ±18.1% vs. 57.2 ±14.9%, p = 0.023). In the logistic regression analysis, the duration of diabetes, systolic and diastolic blood pressure, postprandial glycaemia, HbA(1c) and triglycerides predicted the presence of diabetic microangiopathy independently of age and sex. The CIMT, CAI(x) and PAI(x) were associated with the presence of diabetic microangiopathy only in the univariate model.

CONCLUSIONS

In type 1 diabetic patients with microangiopathic complications, increased carotid IMT and arterial stiffness were observed. The study confirms the role of traditional risk factors for late diabetic complications, such as the duration of the disease and metabolic control in the development of microangiopathy.

Serum CXC ligand 5 is a new marker of subclinical atherosclerosis in type 2 diabetes

OBJECTIVE

To assess the relationship between serum chemokine CXC ligand 5 (CXCL5) and intima-media thickness (IMT) of the common carotid artery, a marker of preclinical atherosclerosis.

DESIGN, PATIENTS AND MEASUREMENTS

We measured the IMT (mean of three segments of both carotid arteries by ultrasonography), serum CXCL5, fasting plasma glucose, serum insulin, serum urea, serum uric acid, HbA1c, serum CRP, adiponectin and lipid profile of 730 Chinese type 2 diabetic participants older than 30 years in a cross-sectional community-based study performed in downtown Shanghai.

RESULTS

Serum CXCL5 correlated with carotid IMT (r = 0·112, P = 0·019) after adjustment for age, gender, serum CRP and HbA1c. Multivariate linear regression analysis demonstrated that age (P = 2·30 × 10(-7) ), gender (P = 2·70 × 10(-2) ), systolic blood pressure (P = 9·26 × 10(-3) ), serum CRP (P = 2·12 × 10(-2) ), low-density lipoprotein cholesterol (P = 2·40 × 10(-2) ), CXCL5 (P = 5·27 × 10(-3) ) and high-density lipoprotein cholesterol (P = 3·80 × 10(-3) ) were independently associated with carotid IMT.

CONCLUSIONS

Serum CXCL5 is an important determinant of carotid artery IMT in patients with type 2 diabetes. The correlation is independent of inflammation and glucose control.

Implications of nocturnal hypertension in children and adolescents with type 1 diabetes

OBJECTIVE

Diabetes is associated with atherogenic risk factors. Hypertension has a major influence on cardiovascular disease in diabetic patients. Ambulatory blood pressure monitoring (ABPM) is useful for identifying nocturnal hypertension. Carotid intima-media thickness (cIMT) is a good measure for identifying subclinical atherosclerosis. This study aimed to evaluate whether nocturnal hypertension affects atherosclerosis in children and adolescents with type 1 diabetes and to investigate the relationship between atherogenic risk factors and cIMT.

RESEARCH DESIGN AND METHODS

ABPM and cIMT were measured in 82 diabetic children and adolescents. We reviewed the hemoglobin A(1c) levels, 24-h urine microalbumin excretion, lipid profiles, and duration of diabetes. Nocturnal hypertension was defined as hypertension observed only at night.

RESULTS

Forty-three (52%) subjects were hypertensive, and 30 subjects were classified as having nocturnal hypertension. cIMT was higher in the nocturnal hypertensive group than in the normotensive group (0.44 ± 0.03 vs. 0.42 ± 0.04 mm, P = 0.026). Among children and adolescents with nonhypertensive blood pressure levels in clinic blood pressure monitoring, cIMT and daytime blood pressure were higher in the nocturnal hypertensive group. All ABPM parameters were significantly related to cIMT in multiple linear regression analysis.

CONCLUSIONS

This study showed significantly increased cIMT and daytime blood pressure in diabetic children and adolescents with nocturnal hypertension. ABPM may be a useful method for detecting the macrovascular complications of type 1 diabetes. Longitudinal studies are needed to find the causes of nocturnal hypertension and to evaluate the effect of nocturnal hypertension on atherosclerosis in type 1 diabetes.

Serum uric acid level and its association with metabolic syndrome and carotid atherosclerosis in patients with type 2 diabetes

Objective

We aimed to investigate whether elevated serum uric acid concentrations are associated with higher risk of metabolic syndrome (MetS) and carotid atherosclerosis in patients with type 2 diabetes.

Methods

We conducted a population-based cross-sectional survey in Shanghai, with a total of 395 men and 631 women age 41 to 92 years. The carotid artery intima-media thickness (IMT) and carotid atherosclerotic plaques (PLQ) were measured by B-mode ultrasound. MetS was defined according to the updated National Cholesterol Education Program Adult Treatment Panel III criteria for Asian Americans.

Results

Uric acid levels were negatively associated with duration of diabetes, fasting plasma glucose, glycohemoglobin, eGFR, HDL-cholesterol (all P < 0.001) and positively with BMI, CRP, waist circumference, triglycerides, systolic blood pressure, ACR, HOMA-IR and IMT (all P < 0.05). In the highest quartile of uric acid levels, the risks were substantially higher for MetS [odds ratio 3.97, (95% confidence interval 2.58-6.13)] (P < 0.001 for trend) and PLQ [odds ratio 2.71 (95% confidence interval 1.62-4.47)] (p = 0.013 for trend) compared with that in the lowest quartile of uric acid levels after multiple adjustment. These associations remained significant after further adjustment for potential confounders.

Conclusions

Serum uric acid level is associated with MetS and is an independent risk factor for carotid atherosclerosis in patients with type 2 diabetes.

Glycolaldehyde induces oxidative stress in the heart: a clue to diabetic cardiomyopathy?

Cardiovascular complications account for 80% of the mortality related to diabetes mellitus. Hyperglycemia is believed to be the major culprit of angiopathy and cardiomyopathy. High glucose levels and oxidative stress cause elevation of Advanced Glycation End-products that are known to contribute to diabetic complications and correlate with many diseases. However, there are few reports describing the effects of glycating agents other than glucose. Here, we aimed to evaluate the effects of glycolaldehyde (GA) on oxidative stress parameters in the heart of Wistar rats. Male Wistar rats received a single injection of GA (10, 50 or 100 mg/Kg) and were sacrificed 6, 12 or 24 h after injection. As indexes of oxidative stress, we quantified protein carbonylation, lipid peroxidation and total reduced thiols. The activities of superoxide dismutase, catalase and glyoxalase I were assayed. Also, the content of N (ɛ)-(carboxymethyl)lysine (CML) was quantified. Glycolaldehyde induced an imbalance in the redox status, with increased protein carbonylation and lipoperoxidation. Catalase and glyoxalase I had a decrease in their activities. Despite the oxidative stress, we observed no increase in CML content. These results suggest that short-chain aldehydes such as GA might have a significant role in the development of diabetic cardiomyopathy.

Levels of oxidized LDL and advanced glycation end products-modified LDL in circulating immune complexes are strongly associated with increased levels of carotid intima-media thickness and its progression in type 1 diabetes

OBJECTIVE

High cholesterol levels in circulating immune complexes (IC), surrogate markers of modified LDL, are associated with increased carotid intima-media thickness (IMT) and cardiovascular events in type 1 diabetes. Different modifications of LDL are involved in IC formation, but which of these are predictive of vascular events is not known. Therefore, we measured oxidized LDL (oxLDL), advanced glycation end products-modified LDL (AGE-LDL), and malondialdehyde-modified LDL (MDA-LDL) in IC and determined their relationship with increased carotid IMT and compared the strength of the association with that observed with conventional risk factors.

RESEARCH DESIGN AND METHODS

Levels of oxLDL, AGE-LDL, and MDA-LDL were measured in circulating IC isolated from sera of 479 patients of the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) cohort, collected at baseline. Internal and common carotid IMT were measured 8 and 14 years later by DCCT/EDIC.

RESULTS

OxLDL, AGE-LDL, and MDA-LDL levels in circulating IC were significantly correlated with diabetes duration, BMI, and lipid and blood pressure, but not with age. Multivariate logistic regression models indicated that individuals in the highest versus lowest quartile of oxLDL and AGE-LDL in IC had a 6.11-fold [confidence interval (CI) 2.51-14.8] and a 6.4-fold (CI 2.53-16.2) increase in the odds of having high carotid IMT, respectively, after adjusting for conventional risk factors. Parallel analyses resulted in odds ratios of 2.62 (CI 1.24, 5.55) for LDL-C, 1.45 (CI 0.69, 3.03) for diastolic blood pressure, and 2.33 (CI 1.09, 4.99) for A1C.

CONCLUSIONS

OxLDL and AGE-LDL in circulating IC were significantly associated with progression and increased levels of carotid IMT in type 1 diabetes.

Repeated gene transfection impairs the engraftment of transplanted porcine neonatal pancreatic cells

BACKGROUND

Previously, we reported that neonatal porcine pancreatic cells transfected with hepatocyte growth factor (HGF) gene in an Epstein-Barr virus (EBV)-based plasmid (pEBVHGF) showed improved proliferation and differentiation compared to those of the control. In this study, we examined if pancreatic cells transfected repeatedly with pEBVHGF can be successfully grafted to control blood glucose in a diabetes mouse model.

METHODS

Neonatal porcine pancreatic cells were cultured as a monolayer and were transfected with pEBVHGF every other day for a total of three transfections. The transfected pancreatic cells were re-aggregated and transplanted into kidney capsules of diabetic nude mice or normal nude mice. Blood glucose level and body weight were measured every other day after transplantation. The engraftment of the transplanted cells and differentiation into beta cells were assessed using immunohistochemistry.

RESULTS

Re-aggregation of the pancreatic cells before transplantation improved engraftment of the cells and facilitated neovascularization of the graft. Right before transplantation, pancreatic cells that were transfected with pEBVHGF and then re-aggregated showed ductal cell marker expression. However, ductal cells disappeared and the cells underwent fibrosis in a diabetes mouse model two to five weeks after transplantation; these mice also did not show controlled blood glucose levels. Furthermore, pancreatic cells transplanted into nude mice with normal blood glucose showed poor graft survival regardless of the type of transfected plasmid (pCEP4, pHGF, or pEBVHGF).

CONCLUSION

For clinical application of transfected neonatal porcine pancreatic cells, further studies are required to develop methods of overcoming the damage for the cells caused by repeated transfection and to re-aggregate them into islet-like structures.

Progression of carotid artery intima-media thickness during 12 years in the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study

OBJECTIVE

This study investigated the long-term effects of intensive diabetic treatment on the progression of atherosclerosis, measured as common carotid artery intima-media thickness (IMT).

RESEARCH DESIGN AND METHODS

A total of 1,116 participants (52% men) in the Epidemiology of Diabetes Interventions and Complications (EDIC) trial, a long-term follow-up of the Diabetes Control and Complications Trial (DCCT), had carotid IMT measurements at EDIC years 1, 6, and 12. Mean age was 46 years, with diabetes duration of 24.5 years at EDIC year 12. Differences in IMT progression between DCCT intensive and conventional treatment groups were examined, controlling for clinical characteristics, IMT reader, and imaging device.

RESULTS

Common carotid IMT progression from EDIC years 1 to 6 was 0.019 mm less in intensive than in conventional (P < 0.0001), and from years 1 to 12 was 0.014 mm less (P = 0.048); but change from years 6 to 12 was similar (intensive - conventional = 0.005 mm, P = 0.379). Mean A1C levels during DCCT and DCCT/EDIC were strongly associated with progression of IMT, explaining most of the differences in IMT progression between DCCT treatment groups. Albuminuria, older age, male sex, smoking, and higher systolic blood pressure were significant predictors of IMT progression.

CONCLUSIONS

Intensive treatment slowed IMT progression for 6 years after the end of DCCT but did not affect IMT progression thereafter (6-12 years). A beneficial effect of prior intensive treatment was still evident 13 years after DCCT ended. These differences were attenuated but not negated after adjusting for blood pressure. These results support the early initiation and continued maintenance of intensive diabetes management in type 1 diabetes to retard atherosclerosis.

Carotid intima-media thickness as a surrogate marker of cardiovascular disease in diabetes

BACKGROUND

Diabetes mellitus is associated with a high risk of cardiovascular disease. Carotid intima-media thickness (CIMT) is increasingly used as a surrogate marker for atherosclerosis. Its use relies on its ability to predict future clinical cardiovascular end points.

METHODS

This review examines the evidence linking CIMT as a surrogate marker of vascular complications in people with type 1 and type 2 diabetes. We have also reviewed the various treatment strategies which have been shown to influence CIMT.

CONCLUSIONS

CIMT measurement is an effective, noninvasive tool which can assist in identifying people with diabetes who are at higher risk of developing microvascular and macrovascular complications. It may also help to evaluate the effectiveness of various treatment strategies used to treat people with diabetes.

A genome-wide association study identifies a novel major locus for glycemic control in type 1 diabetes, as measured by both A1C and glucose

OBJECTIVE

Glycemia is a major risk factor for the development of long-term complications in type 1 diabetes; however, no specific genetic loci have been identified for glycemic control in individuals with type 1 diabetes. To identify such loci in type 1 diabetes, we analyzed longitudinal repeated measures of A1C from the Diabetes Control and Complications Trial.

RESEARCH DESIGN AND METHODS

We performed a genome-wide association study using the mean of quarterly A1C values measured over 6.5 years, separately in the conventional (n = 667) and intensive (n = 637) treatment groups of the DCCT. At loci of interest, linear mixed models were used to take advantage of all the repeated measures. We then assessed the association of these loci with capillary glucose and repeated measures of multiple complications of diabetes.

RESULTS

We identified a major locus for A1C levels in the conventional treatment group near SORCS1 (10q25.1, P = 7 x 10(-10)), which was also associated with mean glucose (P = 2 x 10(-5)). This was confirmed using A1C in the intensive treatment group (P = 0.01). Other loci achieved evidence close to genome-wide significance: 14q32.13 (GSC) and 9p22 (BNC2) in the combined treatment groups and 15q21.3 (WDR72) in the intensive group. Further, these loci gave evidence for association with diabetic complications, specifically SORCS1 with hypoglycemia and BNC2 with renal and retinal complications. We replicated the SORCS1 association in Genetics of Diabetes in Kidneys (GoKinD) study control subjects (P = 0.01) and the BNC2 association with A1C in nondiabetic individuals.

CONCLUSIONS

A major locus for A1C and glucose in individuals with diabetes is near SORCS1. This may influence the design and analysis of genetic studies attempting to identify risk factors for long-term diabetic complications.

Cerebrovascular disease in diabetes mellitus: the role of carotid intima-media thickness

BACKGROUND AND PURPOSE

Cerebrovascular disease in diabetes appears to be less considered than coronary and peripheral disease, the reason being the intrinsic difficulty in finding available diagnostic tools for its early identification. Among these, carotid artery intima-media thickness (cIMT) represents the simplest measurable parameter for pre-atherosclerotic lesions in extra-cranic arteries.

METHODS

The role of cIMT as a surrogate marker of cerebral atherosclerosis and predictor of stroke, its relationship to microangiopathy and chronic inflammation, along with its role as an outcome parameter in anti-hyperglycemic therapeutical intervention trials in type 2 and 1 diabetes mellitus are discussed in this paper.

RESULTS AND CONCLUSIONS

Carotid IMT is increased in diabetes. It is an independent predictor of stroke, in particular of the ischemic subtype, and of stroke recurrence in diabetic, as well as in non-diabetic populations. A possible role of cIMT as a predictor of microangiopathy has also been suggested, but it needs further investigation. A weak association with chronic inflammation has been demonstrated in diabetic patients. Carotid IMT has been successfully employed as an outcome parameter for several anti-hyperglycemic therapeutic trials. However data on cIMT as a predictor of cerebrovascular disease are scarce in diabetic patients, particularly in type 1 diabetes, and more studies are needed to define the risk of cerebrovascular disease in diabetic patients.