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Background: Data are lacking on the comparative effectiveness of commonly used glucose-lowering medications, when added to metformin, with respect to microvascular and cardiovascular disease outcomes in persons with type 2 diabetes., Methods: We assessed the comparative effectiveness of four commonly used glucose-lowering medications, added to metformin, in achieving and maintaining a glycated hemoglobin level of less than 7.0% in participants with type 2 diabetes. The randomly assigned therapies were insulin glargine U-100 (hereafter, glargine), glimepiride, liraglutide, and sitagliptin. Prespecified secondary outcomes with respect to microvascular and cardiovascular disease included hypertension and dyslipidemia, confirmed moderately or severely increased albuminuria or an estimated glomerular filtration rate of less than 60 ml per minute per 1.73 m 2 of body-surface area, diabetic peripheral neuropathy assessed with the Michigan Neuropathy Screening Instrument, cardiovascular events (major adverse cardiovascular events [MACE], hospitalization for heart failure, or an aggregate outcome of any cardiovascular event), and death. Hazard ratios are presented with 95% confidence limits that are not adjusted for multiple comparisons., Results: During a mean 5.0 years of follow-up in 5047 participants, there were no material differences among the interventions with respect to the development of hypertension or dyslipidemia or with respect to microvascular outcomes; the mean overall rate (i.e., events per 100 participant-years) of moderately increased albuminuria levels was 2.6, of severely increased albuminuria levels 1.1, of renal impairment 2.9, and of diabetic peripheral neuropathy 16.7. The treatment groups did not differ with respect to MACE (overall rate, 1.0), hospitalization for heart failure (0.4), death from cardiovascular causes (0.3), or all deaths (0.6). There were small differences with respect to rates of any cardiovascular disease, with 1.9, 1.9, 1.4, and 2.0 in the glargine, glimepiride, liraglutide, and sitagliptin groups, respectively. When one treatment was compared with the combined results of the other three treatments, the hazard ratios for any cardiovascular disease were 1.1 (95% confidence interval [CI], 0.9 to 1.3) in the glargine group, 1.1 (95% CI, 0.9 to 1.4) in the glimepiride group, 0.7 (95% CI, 0.6 to 0.9) in the liraglutide group, and 1.2 (95% CI, 1.0 to 1.5) in the sitagliptin group., Conclusions: In participants with type 2 diabetes, the incidences of microvascular complications and death were not materially different among the four treatment groups. The findings indicated possible differences among the groups in the incidence of any cardiovascular disease. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others; GRADE ClinicalTrials.gov number, NCT01794143.)., (Copyright © 2022 Massachusetts Medical Society.)

Importance: The lower risk of cardiovascular disease (CVD) among women compared with men in the general population may be diminished among those with diabetes., Objective: To evaluate cardiometabolic risk factors and their management in association with CVD events in women vs men with type 1 diabetes enrolled in the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study., Design, Setting, and Participants: This cohort study used data obtained during the combined DCCT (randomized clinical trial, conducted 1983-1993) and EDIC (observational study, conducted 1994 to present) studies through April 30, 2018 (mean [SD] follow-up, 28.8 [5.8] years), at 27 clinical centers in the US and Canada. Data analyses were performed between July 2021 and April 2022., Exposure: During the DCCT phase, patients were randomized to intensive vs conventional diabetes therapy., Main Outcomes and Measures: Cardiometabolic risk factors and CVD events were assessed via detailed medical history and focused physical examinations. Blood and urine samples were assayed centrally. CVD events were adjudicated by a review committee. Linear mixed models and Cox proportional hazards models evaluated sex differences in cardiometabolic risk factors and CVD risk over follow-up., Results: A total of 1441 participants with type 1 diabetes (mean [SD] age at DCCT baseline, 26.8 [7.1] years; 761 [52.8%] men; 1390 [96.5%] non-Hispanic White) were included. Over the duration of the study, compared with men, women had significantly lower body mass index (BMI, calculated as weight in kilograms divided by height in meters squared; β = -0.43 [SE, 0.16]; P = .006), waist circumference (β = -10.56 cm [SE, 0.52 cm]; P < .001), blood pressure (systolic: β = -5.77 mm Hg [SE, 0.35 mm Hg]; P < .001; diastolic: β = -3.23 mm Hg [SE, 0.26 mm Hg]; P < .001), and triglyceride levels (β = -10.10 mg/dL [SE, 1.98 mg/dL]; P < .001); higher HDL cholesterol levels (β = 9.36 mg/dL [SE, 0.57 mg/dL]; P < .001); and similar LDL cholesterol levels (β = -0.76 mg/dL [SE, 1.22 mg/dL]; P = .53). Women, compared with men, achieved recommended targets more frequently for blood pressure (ie, <130/80 mm Hg: 90.0% vs 77.4%; P < .001) and triglycerides (ie, <150 mg/dL: 97.3% vs 90.5%; P < .001). However, sex-specific HDL cholesterol targets (ie, ≥50 mg/dL for women, ≥40 mg/dL for men) were achieved less often (74.3% vs 86.6%; P < .001) and cardioprotective medications were used less frequently in women than men (ie, angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker: 29.6% [95% CI, 25.7%-33.9%] vs 40.0% [95% CI, 36.1%-44.0%]; P = .001; lipid-lowering medication: 25.3% [95% CI, 22.1%-28.7%] vs 39.6% [95% CI, 36.1%-43.2%]; P < .001). Women also had significantly higher pulse rates (mean [SD], 75.2 [6.8] beats per minute vs 71.8 [6.9] beats per minute; P < .001) and hemoglobin A1c levels (mean [SD], 8.3% [1.0%] vs 8.1% [1.0%]; P = .01) and achieved targets for tighter glycemic control less often than men (ie, hemoglobin A1c <7%: 11.2% [95% CI, 9.3%-13.3%] vs 14.0% [95% CI, 12.0%-16.3%]; P = .03)., Conclusions and Relevance: These findings suggest that despite a more favorable cardiometabolic risk factor profile, women with type 1 diabetes did not have a significantly lower CVD event burden than men, suggesting a greater clinical impact of cardiometabolic risk factors in women vs men with diabetes. These findings call for conscientious optimization of the control of CVD risk factors in women with type 1 diabetes.

Objective: The role of genetic factors in the risk of cardiovascular disease (CVD) for patients with type 1 diabetes (T1D) remains unknown. We therefore examined whether previously identified genetic factors for coronary artery disease (CAD) are associated with the risk of CVD above and beyond established demographic and clinical factors in the Diabetes Control and Complications Trial (DCCT)/Epidemiology of Diabetes Interventions and Complications (EDIC) study., Research Design and Methods: Polygenic risk scores (PRS) and individual genetic variants identified in previous studies were obtained from genome-wide genotyping performed in 1,371 DCCT/EDIC participants. Two composite CVD outcomes were considered: major adverse cardiovascular events (MACE) (CVD death or nonfatal myocardial infarction [MI] or stroke) and any CVD (MACE plus confirmed angina, silent MI, revascularization, or congestive heart failure). Cox proportional hazards models assessed the association between the genetic factors and the risk of CVD with adjustment for other factors (including age, lipids, blood pressure, and glycemia)., Results: CAD PRS was strongly associated with the subsequent risk of any CVD (42% and 38% higher risk per 1-SD increase in unadjusted and fully adjusted models, respectively; P < 0.0001) and with the risk of MACE (50% and 40% higher risk per 1-SD increase in unadjusted and fully adjusted models, respectively; P < 0.0001). Several individual single nucleotide polymorphisms were also nominally associated with the risk of any CVD and MACE., Conclusions: Genetic factors are associated with the risk of subsequent CVD in individuals with T1D above and beyond the effect of established risk factors such as age, lipids, blood pressure, and glycemia., (© 2021 by the American Diabetes Association.)

Aims: We assessed whether and to what extent established cardiovascular disease (CVD) risk factors moderate (enhance/reduce) the effect of hyperglycemia on CVD outcomes in the long-term follow-up of the Diabetes Control and Complications Trial type 1 diabetes (T1D) cohort (N = 1441)., Methods: Moderation of the effect of glycemia on subsequent risk of major adverse cardiovascular events (MACE: fatal or non-fatal myocardial infarction or stroke) and any-CVD (MACE plus confirmed angina, silent MI, revascularization, or congestive heart failure) was assessed separately using interaction terms between HbA1c and other risk factors in Cox proportional hazards models., Results: Over a median follow-up of 29 years, there were 120 MACE cases and 239 any-CVD cases. Higher pulse, higher triglycerides, use of calcium channel blockers, and presence of neuropathy individually enhanced (p < 0.01) the effect of glycemia on any-CVD. Higher pulse and triglyceride levels, albumin excretion rate, hypertension, and no family history of type 2 diabetes enhanced (p < 0.01) the effect of glycemia on MACE., Conclusions: Such moderation analyses identify subgroups with increased CVD risk who might especially benefit from earlier and/or more intensive glycemic control. Interventions treating modifiable moderating factors may independently reduce the risk of CVD and also reduce the risk associated with a higher HbA1c., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Objective: To examine the effects of an intensive lifestyle intervention (ILI) on cardiovascular disease (CVD), the Action for Health in Diabetes (Look AHEAD) trial randomized 5,145 participants with type 2 diabetes and overweight/obesity to a ILI or diabetes support and education. Although the primary outcome did not differ between the groups, there was suggestive evidence of heterogeneity for prespecified baseline CVD history subgroups (interaction P = 0.063). Event rates were higher in the ILI group among those with a CVD history (hazard ratio 1.13 [95% CI: 0.90-1.41]) and lower among those without CVD (hazard ratio 0.86 [95% CI: 0.72-1.02])., Methods: This study conducted post hoc analyses of the rates of the primary composite outcome and components, adjudicated cardiovascular death, nonfatal myocardial infarction (MI), stroke, and hospitalization for angina, as well as three secondary composite cardiovascular outcomes., Results: Interaction P values for the primary and two secondary composites were similar (0.060-0.064). Of components, the interaction was significant for nonfatal MI (P = 0.035). This interaction was not due to confounding by baseline variables, different intervention responses for weight loss and physical fitness, or hypoglycemic events. In those with a CVD history, statin use was high and similar by group. In those without a CVD history, low-density lipoprotein cholesterol levels were higher (P = 0.003) and statin use was lower (P ≤ 0.001) in the ILI group., Conclusions: Intervention response heterogeneity was significant for nonfatal MI. Response heterogeneity may need consideration in a CVD-outcome trial design., (© 2020 The Obesity Society.)

The global epidemic of type 2 diabetes has prompted numerous studies and public health efforts to reduce its development. A variety of interventions, including lifestyle modifications and pharmacological agents directed at ameliorating the major risk factors for type 2 diabetes, are of proven efficacy in reducing the development of type 2 diabetes in people with impaired glucose tolerance. While prevention of the hyperglycaemia characteristic of diabetes is arguably an important, clinically relevant outcome, a more compelling outcome with greater clinical significance is the prevention or reduction of the relatively diabetes-specific microvascular and less-specific cardiovascular disease (CVD) complications associated with diabetes. These complications cause the majority of morbidity and excess mortality associated with diabetes. Any reduction in diabetes should, logically, also reduce the occurrence of its long-term complications; however, most diabetes prevention trials have not been of sufficient duration to allow such an evaluation. The limited long-term data, largely from the Da Qing Diabetes Prevention Study (DQDPS) and the Diabetes Prevention Program (DPP) and their respective follow-up studies (DQDPOS and DPPOS), suggest a reduction in microvascular complications and amelioration of CVD risk factors. Only the DQDPOS and Study to Prevent Non-Insulin-Dependent Diabetes Mellitus (STOP-NIDDM) studies have shown a reduction in CVD events and only DQDPOS has demonstrated a decrease in CVD and overall mortality. While these limited data are promising, whether diabetes prevention directly reduces complication-related morbidity and mortality remains unclear. Longer follow-up of prevention studies is needed to supplement the limited current clinical trial data, to help differentiate the effects of diabetes prevention itself from the means used to reduce diabetes development and to understand the balance among benefits, risks and costs of prevention.

Context: For decades, there has been epidemiologic evidence linking chronic toxic metal exposure with cardiovascular disease, suggesting a therapeutic role for metal chelation. Given the lack of compelling scientific evidence, however, the indications for metal chelation were never clearly defined. To determine the safety and efficacy of chelation therapy, the National Institutes of Health funded the Trial to Assess Chelation Therapy (TACT). TACT was the first double-blind, randomized, controlled trial to demonstrate an improvement in cardiovascular outcomes with edetate disodium therapy in patients with prior myocardial infarction. The therapeutic benefit was striking among the prespecified subgroup of patients with diabetes., Design: We review the published literature focusing on the atherogenic nature of diabetes, as well as available evidence from clinical trials, complete and in progress, of metal chelation with edetate disodium therapy in patients with diabetes., Results: The TACT results support the concept that ubiquitous toxic metals such as lead and cadmium may be modifiable risk factors for cardiovascular disease, particularly in patients with diabetes., Conclusions: The purpose of this review is to discuss the potential mechanisms unifying the pathogenesis of atherogenic factors in diabetes with toxic metal exposure, and the potential role of metal chelation., (Copyright © 2019 Endocrine Society.)

Aims/hypothesis: Chronic hyperglycaemia, as measured by HbA 1c levels, is a major risk factor for atherosclerosis and cardiovascular disease (CVD) in type 1 diabetes. Our aim was to describe the degree to which the effect of HbA 1c on the risk of CVD is mediated by its effect on traditional risk factors over time, and how these mediation pathways change over time., Methods: The DCCT and its observational follow-up study, the Epidemiology of Diabetes Interventions and Complications (EDIC), followed 1441 participants for a mean of 27 years, with periodic measurement of HbA 1c and risk factors over time. We assessed the proportion of the HbA 1c effect on risk of CVD that was mediated through its effects on systolic BP (SBP), pulse rate, triacylglycerols and LDL-cholesterol (LDLc) levels, and how the proportion mediated changed over time., Results: The association of HbA 1c with CVD outcomes was stable over time, while that of traditional risk factors (SBP, pulse rate, triacylglycerols and LDLc) increased. At 10 years of follow-up, the effect of HbA 1c on 10 year CVD risk was minimally mediated by SBP (2.7%), increasing to 26% at 20 years. Likewise, from 10 year follow-up to 20 year follow-up, the proportion of HbA 1c effect mediated through pulse rate increased from 6.3% to 29.3%, through triacylglycerols from 2.2% to 22.4%, and through LDLc from 9.2% to 30.7%., Conclusions/interpretation: As participants age, the predictive association of mean HbA 1c on subsequent CVD events is increasingly mediated by its effect on standard risk factors. Thus, management of traditional non-glycaemic CVD risk factors may have increasing benefits in an ageing type 1 diabetes population with longstanding hyperglycaemia., Trial Registration: ClinicalTrials.gov NCT00360893 and NCT00360815.

Background: Findings from the Look AHEAD trial showed no significant reductions in the primary outcome of cardiovascular disease incidence in adults with type 2 diabetes randomly assigned to an intensive lifestyle intervention for weight loss compared with those randomly assigned to diabetes support and education (control). We examined whether the incidence of cardiovascular disease in Look AHEAD varied by changes in weight or fitness., Methods: Look AHEAD was a randomised clinical trial done at 16 clinical sites in the USA, recruiting patients from Aug 22, 2001, to April 30, 2004. In the trial, 5145 overweight or obese adults aged 45-76 years with type 2 diabetes were assigned (1:1) to an intensive lifestyle intervention or diabetes support and education. In this observational, post-hoc analysis, we examined the association of magnitude of weight loss and fitness change over the first year with incidence of cardiovascular disease. The primary outcome of the trial and of this analysis was a composite of death from cardiovascular causes, non-fatal acute myocardial infarction, non-fatal stroke, or admission to hospital for angina. The secondary outcome included the same indices plus coronary artery bypass grafting, carotid endartectomy, percutaneous coronary intervention, hospitalisation for congestive heart failure, peripheral vascular disease, or total mortality. We adjusted analyses for baseline differences in weight or fitness, demographic characteristics, and risk factors for cardiovascular disease. The Look AHEAD trial is registered with ClinicalTrials.gov, number NCT00017953., Findings: For the analyses related to weight change, we excluded 311 ineligible participants, leaving a population of 4834; for the analyses related to fitness change, we excluded 739 participants, leaving a population of 4406. In analyses of the full cohort (ie, combining both study groups), over a median 10·2 years of follow-up (IQR 9·5-10·7), individuals who lost at least 10% of their bodyweight in the first year of the study had a 21% lower risk of the primary outcome (adjusted hazard ratio [HR] 0·79, 95% CI 0·64-0·98; p=0·034) and a 24% reduced risk of the secondary outcome (adjusted HR 0·76, 95% CI 0·63-0·91; p=0·003) compared with individuals with stable weight or weight gain. Achieving an increase of at least 2 metabolic equivalents in fitness change was associated with a significant reduction in the secondary outcome (adjusted HR 0·77, 95% CI 0·61-0·96; p=0·023) but not the primary outcome (adjusted HR 0·78, 0·60-1·03; p=0·079). In analyses treating the control group as the reference group, participants in the intensive lifestyle intervention group who lost at least 10% of their bodyweight had a 20% lower risk of the primary outcome (adjusted HR 0·80, 95% CI 0·65-0·99; p=0·039), and a 21% lower risk of the secondary outcome (adjusted HR 0·79, 95% CI 0·66-0·95; p=0·011); however, change in fitness was not significantly associated with a change in the primary outcome., Interpretation: The results of this post-hoc analysis of Look AHEAD suggest an association between the magnitude of weight loss and incidence of cardiovascular disease in people with type 2 diabetes. These findings suggest a need to continue to refine approaches to identify individuals who are most likely to benefit from lifestyle interventions and to develop strategies to improve the magnitude of sustained weight loss with lifestyle interventions., Funding: US National Institute of Diabetes and Digestive and Kidney Diseases., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Understanding of the long-term clinical outcomes associated with bariatric surgery has recently been advanced. Research related to the sequelae of diabetes-in particular, long-term microvascular and macrovascular complications-in patients who undergo weight-loss surgery is imperative to this pursuit. While numerous randomized control trials have assessed glucose control with bariatric surgery compared with intensive medical therapy, bariatric surgery outcome data relating to microvascular and macrovascular complications have been limited to observational studies and nonrandomized clinical trials. As a result, whether bariatric surgery is associated with a long-term reduction in microvascular and macrovascular complications when compared with current intensive glycemic control therapy cannot be determined because the evidence is insufficient. However, the consistent salutary effects of bariatric surgery on diabetes remission and glycemic improvement support the opportunity (and need) to conduct high-quality studies of bariatric surgery versus intensive glucose control. This review provides relevant background information related to the treatment of diabetes, hyperglycemia, and long-term complications; reports clinical findings (to date) with bariatric surgery; and identifies ongoing research focusing on long-term vascular outcomes associated with bariatric surgery., (© 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.)

Objective: To assess the relative impact of an intensive lifestyle intervention (ILI) on use and costs of health care within the Look AHEAD trial., Research Design and Methods: A total of 5,121 overweight or obese adults with type 2 diabetes were randomly assigned to an ILI that promoted weight loss or to a comparison condition of diabetes support and education (DSE). Use and costs of health-care services were recorded across an average of 10 years., Results: ILI led to reductions in annual hospitalizations (11%, P = 0.004), hospital days (15%, P = 0.01), and number of medications (6%, P < 0.001), resulting in cost savings for hospitalization (10%, P = 0.04) and medication (7%, P < 0.001). ILI produced a mean relative per-person 10-year cost savings of $5,280 (95% CI 3,385-7,175); however, these were not evident among individuals with a history of cardiovascular disease., Conclusions: Compared with DSE over 10 years, ILI participants had fewer hospitalizations, fewer medications, and lower health-care costs., (© 2014 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.)

The association of chronic glycemia, measured by HbA(1c), with long-term complications of type 1 diabetes has been well established in the Diabetes Control and Complications Trial (DCCT) and other studies. The role of intermediate-term and acute glycemia and of glucose variability on microvascular and cardiovascular disease (CVD) is less clear. In order to examine the interrelationships among long-term, intermediate-term, and acute measures of glucose and its daily variability, we compared HbA(1c), glycated albumin (GA), and seven-point glucose profile concentrations measured longitudinally in a case-cohort subpopulation of the DCCT. HbA(1c) and GA were closely correlated with each other and with the mean blood glucose (MBG) calculated from the seven-point profile. The associations of glucose variability and postprandial concentrations with HbA(1c) and GA were relatively weak and were further attenuated when MBG was included in multivariate models. In the case-cohort analyses, HbA(1c) and GA had similar associations with retinopathy and nephropathy, which were strengthened when both measures were considered together. Only HbA(1c) was significantly associated with CVD. The demonstrated interrelationships among different measures of glycemia will need to be considered in future analyses of their roles in the development of long-term complications of type 1 diabetes.

Background: Weight loss is recommended for overweight or obese patients with type 2 diabetes on the basis of short-term studies, but long-term effects on cardiovascular disease remain unknown. We examined whether an intensive lifestyle intervention for weight loss would decrease cardiovascular morbidity and mortality among such patients., Methods: In 16 study centers in the United States, we randomly assigned 5145 overweight or obese patients with type 2 diabetes to participate in an intensive lifestyle intervention that promoted weight loss through decreased caloric intake and increased physical activity (intervention group) or to receive diabetes support and education (control group). The primary outcome was a composite of death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for angina during a maximum follow-up of 13.5 years., Results: The trial was stopped early on the basis of a futility analysis when the median follow-up was 9.6 years. Weight loss was greater in the intervention group than in the control group throughout the study (8.6% vs. 0.7% at 1 year; 6.0% vs. 3.5% at study end). The intensive lifestyle intervention also produced greater reductions in glycated hemoglobin and greater initial improvements in fitness and all cardiovascular risk factors, except for low-density-lipoprotein cholesterol levels. The primary outcome occurred in 403 patients in the intervention group and in 418 in the control group (1.83 and 1.92 events per 100 person-years, respectively; hazard ratio in the intervention group, 0.95; 95% confidence interval, 0.83 to 1.09; P=0.51)., Conclusions: An intensive lifestyle intervention focusing on weight loss did not reduce the rate of cardiovascular events in overweight or obese adults with type 2 diabetes. (Funded by the National Institutes of Health and others; Look AHEAD ClinicalTrials.gov number, NCT00017953.).

The Look AHEAD (Action for Health in Diabetes) Study is a long-term clinical trial that aims to determine the cardiovascular disease (CVD) benefits of an intensive lifestyle intervention (ILI) in obese adults with type 2 diabetes. The study was designed to have 90% statistical power to detect an 18% reduction in the CVD event rate in the ILI Group compared to the Diabetes Support and Education (DSE) Group over 10.5 years of follow-up. The original power calculations were based on an expected CVD rate of 3.125% per year in the DSE group; however, a much lower-than-expected rate in the first 2 years of follow-up prompted the Data and Safety Monitoring Board (DSMB) to recommend that the Steering Committee undertake a formal blinded evaluation of these design considerations. The Steering Committee created an Endpoint Working Group (EPWG) that consisted of individuals masked to study data to examine relevant issues. The EPWG considered two primary options: (1) expanding the definition of the primary endpoint and (2) extending follow-up of participants. Ultimately, the EPWG recommended that the Look AHEAD Steering Committee approve both strategies. The DSMB accepted these modifications, rather than recommending that the trial continue with inadequate statistical power. Trialists sometimes need to modify endpoints after launch. This decision should be well justified and should be made by individuals who are fully masked to interim results that could introduce bias. This article describes this process in the Look AHEAD study and places it in the context of recent articles on endpoint modification and recent trials that reported endpoint modification.

Background: We report relationships between cardiovascular disease risk factors and myocardial structure, function, and scar in patients with type 1 diabetes mellitus in the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study., Methods and Results: Cardiac magnetic resonance was obtained in 1017 patients with type 1 diabetes mellitus. Gadolinium cardiac magnetic resonance was also obtained in 741 patients. The mean age was 49±7 years; 52% were men; and mean duration of diabetes mellitus was 28±5 years. Associations of cardiovascular disease risk factors with cardiac magnetic resonance parameters were examined with linear and logistic regression models. History of macroalbuminuria was positively associated with left ventricular mass (by 14.8 g), leading to a significantly higher ratio of left ventricular mass to end-diastolic volume (by 8%). Mean hemoglobin A(1c) levels over the preceding 22 years were inversely associated with end-diastolic volume (-3.0 mL per unit mean hemoglobin A(1c) percent) and stroke volume (-2.3 mL per unit mean hemoglobin A(1c) percent) and positively related to the ratio of elevated left ventricular mass to end-diastolic volume (0.02 g/mL per unit). The overall prevalence of myocardial scar was 4.3% by cardiac magnetic resonance and 1.4% by clinical adjudication of myocardial infarction. Both mean hemoglobin A(1c) (odds ratio, 1.5 [95% confidence interval, 1.0-2.2] per unit) and macroalbuminuria (odds ratio, 3.5 [95% confidence interval, 1.2-9.9]) were significantly associated with myocardial scar and traditional cardiovascular disease risk factors., Conclusions: In addition to traditional cardiovascular disease risk factors, elevated mean hemoglobin A(1c) and macroalbuminuria were significantly associated with alterations in left ventricular structure and function. The prevalence of myocardial scar was 4.3% in this subcohort of DCCT/EDIC participants with relatively preserved renal function. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00360893 and NCT00360815.

Aims: Increased glucose excursions and postprandial hyperglycaemia have been suggested as unique risk factors for cardiovascular disease (CVD) and mortality in patients with diabetes mellitus. Much of the evidence is based on a single 2 h glucose value after oral glucose tolerance testing in epidemiological studies. We examined the association between various indices of glycaemia measured during everyday activities and metabolic CVD risk factors in the A1C-Derived Average Glucose (ADAG) study., Methods: Participants (268 with type 1 diabetes, 159 with type 2 diabetes) completed 16 weeks of intensive continuous glucose monitoring (CGM) and self-monitoring of blood glucose (SMBG). From these data, common indices of postprandial glycaemia, overall hyperglycaemia, glucose variability and HbA₁(c) were derived. The associations between glycaemic indices and known CVD risk factors (lipids, high-sensitivity C-reactive protein and blood pressure) were explored in linear regression models., Results: For both diabetes types, the overall strongest associations with CVD risk factors were seen for the measures of average glycaemia (mean blood glucose and HbA₁(c)). Associations between self-monitored postprandial and fasting glucose and CVD risk factors were weaker, but significant. Measurements of blood glucose variability showed non-significant associations. Overall, calculations based on CGM were not more informative than those based on frequent SMBG., Conclusions/interpretation: Mean glycaemia and HbA₁(c) show consistent and stronger associations with CVD risk factors than fasting glucose or postprandial glucose levels or measures of glucose variability in patients with diabetes.

Objective: The effectiveness of intentional weight loss in reducing cardiovascular disease (CVD) events in type 2 diabetes is unknown. This report describes 1-year changes in CVD risk factors in a trial designed to examine the long-term effects of an intensive lifestyle intervention on the incidence of major CVD events., Research Design and Methods: This study consisted of a multicentered, randomized, controlled trial of 5,145 individuals with type 2 diabetes, aged 45-74 years, with BMI >25 kg/m2 (>27 kg/m2 if taking insulin). An intensive lifestyle intervention (ILI) involving group and individual meetings to achieve and maintain weight loss through decreased caloric intake and increased physical activity was compared with a diabetes support and education (DSE) condition., Results: Participants assigned to ILI lost an average 8.6% of their initial weight vs. 0.7% in DSE group (P < 0.001). Mean fitness increased in ILI by 20.9 vs. 5.8% in DSE (P < 0.001). A greater proportion of ILI participants had reductions in diabetes, hypertension, and lipid-lowering medicines. Mean A1C dropped from 7.3 to 6.6% in ILI (P < 0.001) vs. from 7.3 to 7.2% in DSE. Systolic and diastolic pressure, triglycerides, HDL cholesterol, and urine albumin-to-creatinine ratio improved significantly more in ILI than DSE participants (all P < 0.01)., Conclusions: At 1 year, ILI resulted in clinically significant weight loss in people with type 2 diabetes. This was associated with improved diabetes control and CVD risk factors and reduced medicine use in ILI versus DSE. Continued intervention and follow-up will determine whether these changes are maintained and will reduce CVD risk.

Context: Metabolic risk conferred by adiposity may be due to associated risk factor clustering., Objective: The objective of this study was to assess risk for diabetes or cardiovascular disease (CVD) stratified by body mass index (BMI) and the presence or absence of metabolic syndrome (MetS) or insulin resistance (IR)., Design, Setting, and Participants: This was a community-based, longitudinal study of 2902 people (55% women, mean age 53 yr) without diabetes or CVD in 1989-1992 followed for up to 11 yr. We categorized subjects by normal weight (BMI < 25 kg/m(2)), overweight (25-29.9 kg/m(2)), or obese (>30 kg/m(2)) and by the National Cholesterol Education Program's Adult Treatment Panel MetS or the top quartile of homeostasis model IR. We used proportional hazard models to estimate risk relative to normal weight and no MetS or IR., Main Outcome Measure: Incident type 2 diabetes (treatment or fasting glucose > or = 7 mmol/liter, 141 events) or CVD (myocardial infarction, stroke, or claudication, 252 events) were measured., Results: Among 1056 normal-weight subjects, 7% had MetS and a risk factor-adjusted relative risk for diabetes of 3.97 (95% confidence interval, 1.35-11.6) and for CVD of 3.01 (1.68-5.41). Among 638 obese subjects, 37% did not have MetS or significantly increased risk. Obese subjects with MetS had an adjusted relative risk for diabetes of 10.3 (5.44-19.5) and for CVD of 2.13 (1.43-3.18). Results were similar in analyses of BMI-IR categories., Conclusions: People with normal weight and MetS or IR or with obesity but no MetS or IR were not uncommon in our sample. Risk factor clustering or IR appear to confer much of the risk for diabetes or CVD commonly associated with elevated BMI.

Background: Intensive diabetes therapy aimed at achieving near normoglycemia reduces the risk of microvascular and neurologic complications of type 1 diabetes. We studied whether the use of intensive therapy as compared with conventional therapy during the Diabetes Control and Complications Trial (DCCT) affected the long-term incidence of cardiovascular disease., Methods: The DCCT randomly assigned 1441 patients with type 1 diabetes to intensive or conventional therapy, treating them for a mean of 6.5 years between 1983 and 1993. Ninety-three percent were subsequently followed until February 1, 2005, during the observational Epidemiology of Diabetes Interventions and Complications study. Cardiovascular disease (defined as nonfatal myocardial infarction, stroke, death from cardiovascular disease, confirmed angina, or the need for coronary-artery revascularization) was assessed with standardized measures and classified by an independent committee., Results: During the mean 17 years of follow-up, 46 cardiovascular disease events occurred in 31 patients who had received intensive treatment in the DCCT, as compared with 98 events in 52 patients who had received conventional treatment. Intensive treatment reduced the risk of any cardiovascular disease event by 42 percent (95 percent confidence interval, 9 to 63 percent; P=0.02) and the risk of nonfatal myocardial infarction, stroke, or death from cardiovascular disease by 57 percent (95 percent confidence interval, 12 to 79 percent; P=0.02). The decrease in glycosylated hemoglobin values during the DCCT was significantly associated with most of the positive effects of intensive treatment on the risk of cardiovascular disease. Microalbuminuria and albuminuria were associated with a significant increase in the risk of cardiovascular disease, but differences between treatment groups remained significant (P< or =0.05) after adjusting for these factors., Conclusions: Intensive diabetes therapy has long-term beneficial effects on the risk of cardiovascular disease in patients with type 1 diabetes., (Copyright 2005 Massachusetts Medical Society.)

Objective: The prevalence of type 2 diabetes, especially in developing countries, has grown over the past decades. We performed a controlled clinical study to determine whether a community-based, group-centered public health intervention addressing nutrition and exercise can ameliorate glycemic control and associated cardiovascular risk factors in type 2 diabetic patients in rural Costa Rica., Research Design and Methods: A total of 75 adults with type 2 diabetes, mean age 59 years, were randomly assigned to the intervention group or the control group. All participants received basic diabetes education. The subjects in the intervention group participated in 11 weekly nutrition classes (90 min each session). Subjects for whom exercise was deemed safe also participated in triweekly walking groups (60 min each session). Glycosylated hemoglobin, fasting plasma glucose, total cholesterol, triglycerides, HDL and LDL cholesterol, height, weight, BMI, and blood pressure were measured at baseline and the end of the study (after 12 weeks)., Results: The intervention group lost 1.0 +/- 2.2 kg compared with a weight gain in the control group of 0.4 +/- 2.3 kg (P = 0.028). Fasting plasma glucose decreased 19 +/- 55 mg/dl in the intervention group and increased 16 +/- 78 mg/dl in the control group (P = 0.048). Glycosylated hemoglobin decreased 1.8 +/- 2.3% in the intervention group and 0.4 +/- 2.3% in the control group (P = 0.028)., Conclusions: Glycemic control of type 2 diabetic patients can be improved through community-based, group-centered public health interventions addressing nutrition and exercise. This pilot study provides an economically feasible model for programs that aim to improve the health status of people with type 2 diabetes.

Objective: To test the hypothesis that fasting hyperglycemia (FHG) and 2-h postchallenge glycemia (2hPG) independently increase the risk for cardiovascular disease (CVD)., Research Design and Methods: During 1991-1995, we examined 3,370 subjects from the Framingham Offspring Study who were free from clinical CVD (coronary heart disease, stroke, or intermittent claudication) or medication-treated diabetes, and we followed them for 4 years for incident CVD events. We used proportional-hazards regression to assess the risk associated with FHG (fasting plasma glucose > or =7.0 mmol/l) and 2hPG, independent of the risk predicted by standard CVD risk factors., Results: Mean subject age was 54 years, 54% were women, and previously undiagnosed diabetes was present in 3.2% by FHG and 4.9% (164) by FHG or a 2hPG > or =11.1 mmol/l. Of these 164 subjects, 55 (33.5%) had 2hPG > or =11.1 without FHG, but these 55 subjects represented only 1.7% of the 3,261 subjects without FHG. During 12,242 person-years of follow-up, there were 118 CVD events. In separate sex- and CVD risk-adjusted models, relative risk (RR) for CVD with fasting plasma glucose > or =7.0 mmol/l was 2.8 (95% CI 1.6-5.0); RR for CVD per 2.1 mmol/l increase in 2hPG was 1.2 (1.1-1.3). When modeled together, the RR for FHG decreased to 1.5 (0.7-3.6), whereas the RR for 2hPG remained significant (1.1, 1.02-1.3). The c-statistic for a model including CVD risk factors alone was 0.744; with addition of FHG, it was 0.746, and with FHG and 2hPG, it was 0.752., Conclusions: Postchallenge hyperglycemia is an independent risk factor for CVD, but the marginal predictive value of 2hPG beyond knowledge of standard CVD risk factors is small.

Objective: To assess current and long-term associations of glycemia with microalbuminuria, a marker of generalized endothelial injury., Research Design and Methods: We measured clinical characteristics, fasting plasma glucose, and the urinary albumin-to-creatinine ratio (UACR) in 1,311 men and 1,518 women attending the sixth examination cycle (1995-1998) of the Framingham Offspring Study. After excluding participants with diabetes or cardiovascular disease (CVD) at the baseline examination (1971-1974), we used fasting glucose measured at baseline, examination 6, and at least two additional examinations from 1974 to 1995 in regression models to predict risk for microalbuminuria (UACR > or = 30 mg/g) associated with baseline, current, and 24-year time-integrated glycemia., Results: Microalbuminuria was present in 9.5% of men and 13.4% of women. Among men, age-adjusted odds ratios (95% CI) for microalbuminuria associated with each 0.28 mmol/l (5 mg/dl) increase in baseline, current, and time-integrated glucose levels were 1.12 (1.00-1.16), 1.08 (1.05-1.10), and 1.16 (1.11-1.21), respectively. These effects persisted after adjustment for systolic blood pressure and other confounders. Higher glucose levels also predicted incident diabetes and CVD. Mean time-integrated glucose levels were highest among men who developed both CVD and microalbuminuria (SE 6.82 +/- 0.16 mmol/l), intermediate among men with either condition (6.03 +/- 0.65 mmol/l), and lowest among men with neither condition (5.49 +/- 0.02 mmol/l; P < 0.001 for all pairwise comparisons). We observed similar associations in women., Conclusions: Long-term hyperglycemia and subdiabetic glycemia increase risk for microalbuminuria. Microalbuminuria, type 2 diabetes, and CVD seem to arise together over the course of decades, consistent with the hypothesis that they share a common antecedent.

Background: Categorical definitions for glucose intolerance imply that risk thresholds exist, but metabolic risk for type 2 diabetes mellitus or cardiovascular disease may increase continuously as glucose intolerance increases., Objective: To examine the distributions of the following metabolic risk factors across the spectrum of glucose tolerance: overall and central obesity, hypertension, low levels of high-density lipoprotein cholesterol, and increased triglyceride and insulin levels., Design: Cross-sectional analysis., Setting: The community-based Framingham Offspring Study., Participants: 2583 adults without previously diagnosed diabetes., Measurements: Clinical data; fasting glucose, insulin, and lipid levels; and glucose and insulin levels taken 2 hours after oral challenge were collected from 1991 to 1993. Glucose tolerance was determined by 1980 World Health Organization criteria. Patients with normal glucose tolerance were categorized into quintiles of fasting glucose. The distributions of each metabolic risk factor and the metabolic sum of the six risk factors were assessed across seven categories from the lowest quintile of normal fasting glucose level through impaired glucose tolerance and previously undiagnosed diabetes., Results: The mean age of patients was 54 years (range, 26 to 82 years); 52.7% of patients were women. Glucose tolerance testing found that 12.7% of patients had impaired glucose tolerance and 4.8% had previously undiagnosed diabetes. Multivariable-adjusted mean measures of risk factors and odds ratios for obesity, elevated waist-to-hip ratio, hypertension, low levels of high-density lipoprotein cholesterol, elevated triglyceride levels, and hyperinsulinemia showed continuous increases across the spectrum of nondiabetic glucose tolerance. Although a threshold effect near the upper range of nondiabetic glucose tolerance could not be ruled out for triglyceride levels in men and for insulin levels 2 hours after oral challenge in men and women, no other metabolic risk factors showed clear evidence of thresholds for increased risk., Conclusions: Metabolic risk factors for type 2 diabetes mellitus and for cardiovascular disease worsen continuously across the spectrum of glucose tolerance categories, beginning in the lowest quintiles of normal fasting glucose level.

Purpose: Cardiovascular disease is a major cause of morbidity and death in non-insulin-dependent diabetes mellitus (NIDDM). While hyperglycemia is clearly related to diabetic microvascular complications, it contribution to large-vessel atherosclerosis is controversial., Patients and Methods: We performed an analysis of the association between glycemic control and prevalent cardiovascular disease in 1,539 participants in the NIDDM Patient Outcomes Research Team study who were under usual care in a health maintenance organization. Prevalent cardiovascular disease and its risk factors were identified by self-administered questionnaire. Cardiovascular disease was defined by the presence of coronary heart disease, peripheral vascular disease, and/or cerebrovascular disease. Glycohemoglobin and lipid levels were obtained from a computerized laboratory database., Results: The mean age of participants was 63 years (range 31 to 91); 51% were women. The mean duration of NIDDM was 9 years (range < 1 to 50), 35% took insulin, and 48% took sulfonylureas. Mean glycohemoglobin was 10.6%. Sixty percent had hypertension, 16% currently smoked cigarettes, and the mean total high-density lipoprotein (HDL) cholesterol ratio was 5.7. Fifty-one percent had cardiovascular disease. Cardiovascular disease prevalence remained constant across increasing quartiles of glycohemoglobin for both men and women. In contrast, prevalent cardiovascular disease was associated with established cardiovascular disease risk factors including age (67 versus 59 years, P < 0.0001), hypertension (66% versus 54%, P < 0.0001), current cigarette smoking (17% versus 13%, P < 0.005), and total/HDL cholesterol ratio (5.9 versus 5.6, P < 0.005). Cardiovascular disease was also associated with duration of NIDDM (11 versus 8 years, P < 0.0001). In multiple logistic regression analysis controlling for established cardiovascular disease risk factors and diabetes duration and therapy, glycohemoglobin remained unassociated with cardiovascular disease., Conclusions: Glycemic control is not associated with prevalent cardiovascular disease in this large population of individuals with NIDDM. Conventional cardiovascular disease risk factors are independently associated with cardiovascular disease and be a more promising focus for clinical intervention to reduce atherosclerotic complications in NIDDM.

We studied the cross-sectional relationship between HbA1c and cardiovascular disease (CVD) in the survivors of the original cohort of the Framingham Heart Study (n = 1045). HbA1c was significantly related to prevalent CVD among women but not men. HbA1c was also related to hypertension and to the ratio of total to high-density lipoprotein cholesterol levels. In regression analyses that controlled for these and other potential risk factors, HbA1c remained significantly related to CVD among women. The relative odds of CVD increased 1.39-fold (95% confidence interval 1.06-1.83) for increases in HbA1c of 1% (e.g., for HbA1c from 5 to 6%). The relationship was not weakened when known diabetic subjects or subjects taking beta-blocker or thiazide medications were excluded from analysis. In contrast, there was no significant relationship between "casual" blood glucose and prevalent CVD. Our results reveal a strong, significant, independent association between hyperglycemia, measured by HbA1c, and CVD among older women.