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The U.S. Food and Drug Administration (FDA) issued guidance on requirements to assess cardiovascular disease (CVD) risk with drugs being developed for approval for clinical use. The guidance was triggered by a meta-analysis published by Nissen and Wolski that suggested an increased risk for myocardial infarction with the use of rosiglitazone. This article discusses controversies around CVD trials in diabetes beginning with the University Group Diabetes Program. This is followed by a brief description of the FDA guidance for evaluating CVD risk with glucose-lowering medications. Limitations of meta-analyses of data from phase 2 and 3 (phase 2/3) trials to inform CVD risk are highlighted. These include the differences between patient characteristics in phase 2/3 trials and those in cardiovascular outcome trials (CVOTs) and the relatively short exposure time in phase 2/3 trials. The differences may partly explain the observed disparity between phase 2/3 meta-analyses and the results of completed CVOTs. Approaches to understanding CVD risk with a new medication should get to the answer about risk as efficiently as possible to minimize any potential harm to patients. In that context, we discuss options for clinical trial design and an alternative approach for statistical analyses.

There is a link between Oliver Wendell Holmes' poem “The One-Hoss Shay” (1) and every patient with diabetes who has ever received a kidney or pancreas transplant. Yet, most of the 4,128 diabetes patients in the U.S. who received renal transplants in 2011 (2) and the 1,051 diabetes patients who received a pancreas transplant in 2011 (3) do not know how Dr. Frederick C. Goetz (1922–2012) used this delightful poem as parallel to how the medical profession viewed patients with diabetes. Dr. Goetz, who always preferred to be addressed as “Fred” by any who knew him, played a seminal role in assuring that both renal and pancreas transplantation were available to suitable patients with diabetes. While today this is considered a standard of clinical care, Fred maintained his equanimity in the face of much skepticism and criticism—often from friends and colleagues. This profile outlines Fred’s role in the history of renal and pancreas transplantation, but also strives to capture some of the “essence” of Frederick C. Goetz—as a caregiver, physician, scientist, and teacher. This profile is written from the perspective of three physicians, each of whom first met Fred while they were medical students at the University of Minnesota and whose collective observations and collaboration with Fred spanned more than three decades of his academic career. Fred was born and raised in Fond du Lac, WI. He graduated from Harvard College (1943) and Harvard Medical School (1946). He served in the U.S. Army as a physician in Korea where he met his future wife, Mary Rose Riordan. After a residency, chief residency, and fellowship (with Dr. George Thorn) at Massachusetts General Hospital, he joined the University of Minnesota as the Director of Diabetes Research. His career was focused on diabetes and its complications. His personal life was filled with interests …

OBJECTIVE To test the hypothesis that exenatide twice daily reduces the relative incidence of cardiovascular disease (CVD) events among patients with type 2 diabetes compared with other glucose-lowering agent(s). RESEARCH DESIGN AND METHODS A retrospective database analysis was performed of the LifeLink database of medical and pharmaceutical insurance claims for June 2005 through March 2009. Patients with no history in the preceding 9 months of myocardial infarction, ischemic stroke, or coronary revascularization procedure were assigned to the exenatide-initiated or non–exenatide-initiated cohorts based on the first new prescription filled and reassigned if exenatide was prescribed or discontinued. Incident CVD events (myocardial infarction, ischemic stroke, or coronary revascularization procedure) were identified by ICD-9-CM diagnosis codes. Patient outcomes were adjusted for differences in clinical and demographic characteristics and compared using propensity score–weighted discrete time survival analysis with time-varying exposure to exenatide. RESULTS A total of 39,275 patients with type 2 diabetes were treated with exenatide twice daily, and 381,218 patients were treated with other glucose-lowering therapies. Patients who initiated exenatide were more likely to have prior ischemic heart disease, obesity, hyperlipidemia, hypertension, and/or other comorbidities at baseline. Exenatide-treated patients were less likely to have a CVD event than non–exenatide-treated patients (hazard ratio 0.81; 95% CI 0.68–0.95; P = 0.01) and lower rates of CVD-related hospitalization (0.88; 0.79–0.98; P = 0.02) and all-cause hospitalization (0.94; 0.91–0.97; P < 0.001). CONCLUSIONS Exenatide twice-daily treatment was associated with a lower risk of CVD events and hospitalizations than treatment with other glucose-lowering therapies.

OBJECTIVE Intensive therapy targeting normal blood glucose increased mortality compared with standard treatment in a randomized clinical trial of 10,251 participants with type 2 diabetes at high-risk for cardiovascular disease (CVD) events. We evaluated whether the presence of cardiac autonomic neuropathy (CAN) at baseline modified the effect of intensive compared with standard glycemia treatment on mortality outcomes in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial participants. RESEARCH DESIGN AND METHODS CAN was assessed by measures of heart rate variability (HRV) and QT index (QTI) computed from 10-s resting electrocardiograms in 8,135 ACCORD trial participants with valid measurements (mean age 63.0 years, 40% women). Prespecified CAN definitions included a composite of the lowest quartile of HRV and highest QTI quartile in the presence or absence of peripheral neuropathy. Outcomes were all-cause and CVD mortality. Associations between CAN and mortality were evaluated by proportional hazards analysis, adjusting for treatment group allocation, CVD history, and multiple prespecified baseline covariates. RESULTS During a mean 3.5 years follow-up, there were 329 deaths from all causes. In fully adjusted analyses, participants with baseline CAN were 1.55–2.14 times as likely to die as participants without CAN, depending on the CAN definition used (P < 0.02 for all). The effect of allocation to the intensive group on all-cause and CVD mortality was similar in participants with or without CAN at baseline (Pinteraction > 0.7). CONCLUSIONS Whereas CAN was associated with increased mortality in this high-risk type 2 diabetes cohort, these analyses indicate that participants with CAN at baseline had similar mortality outcomes from intensive compared with standard glycemia treatment in the ACCORD cohort.

Medical nutrition therapy (MNT) is important in preventing diabetes, managing existing diabetes, and preventing, or at least slowing, the rate of development of diabetes complications. It is, therefore, important at all levels of diabetes prevention. MNT is also an integral component of diabetes self-management education (or training). This position statement provides evidence-based recommendations and interventions for diabetes MNT. The previous position statement with accompanying technical review was published in 2002 and modified slightly in 2004. This statement updates previous position statements, focuses on key references published since the year 2000, and uses grading according to the level of evidence available...

OBJECTIVE—Insulin resistance is associated with autonomic dysfunction. An attenuated decrease in heart rate after exercise (or heart rate recovery [HRR]) predicts all-cause mortality and is believed to reflect decreased parasympathetic activity. Utilizing triglyceride/HDL cholesterol concentration as a marker of insulin resistance, we sought to assess the association between insulin resistance and HRR. RESEARCH DESIGN AND METHODS—Our study population included 4,963 healthy adults who participated in the Lipid Research Clinics Prevalence Study and underwent exercise testing. HRR was considered abnormal if it did not drop ≥42 bpm 2 min after completion of exercise. Fasting blood specimens were drawn. RESULTS—Individuals in the highest quartile of triglyceride/HDL cholesterol had a significantly higher prevalence of abnormal HRR (40 vs. 30%, multivariable-adjusted prevalence ratio 1.18, 95% CI 1.01–1.39; P = 0.04). As a continuous variable, an increase in 1 SD of triglyceride–to–HDL cholesterol ratio was associated with a greater likelihood of an abnormal HRR, even after adjusting for >20 covariates (adjusted OR 1.16, 95% CI 1.07–1.25; P < 0.001). During 12 years of follow-up, there were 284 deaths. In age- and sex-adjusted analysis, participants with an abnormal HRR and high triglyceride–to–HDL cholesterol ratio had significantly higher mortality than those with a normal HRR and high triglyceride–to–HDL cholesterol ratio (hazard ratio = 1.49, 95% CI 1.08–2.04; P = 0.015). CONCLUSIONS—HRR is associated with triglyceride–to–HDL cholesterol ratio and identifies patients with insulin resistance who are at increased risk of death.

OBJECTIVE: Hypertriglyceridemia is commonly observed in association with diabetes. Despite cross-sectional studies and isolated longitudinal analyses in patients without coronary artery disease, the suggestion that triglyceride levels are relevant to subsequent cardiovascular events in the setting of diabetes remains controversial. This study evaluates the predictive value of serum triglyceride levels on mortality in post-coronary artery bypass graft (CABG) diabetic patients with subsequent analysis by sex. RESEARCH DESIGN AND METHODS: This longitudinal observational study involving a large metropolitan hospital consists of 1,172 diabetic post-CABG patients (792 men and 380 women) with lipid data collected between the years 1982 and 1992. Cox proportional hazards regression models were used to estimate the risk of mortality and cardiac events associated with triglyceride levels in the highest quartile (> 2.90 mmol/l for men and > 3.12 mmol/l for women). RESULTS: Elevated preoperative serum triglyceride values in post-CABG subjects with diabetes were correlated with increased overall mortality (hazard ratio [HR] 1.26, 95% CI 1.00-1.59). The greatest influence of triglyceride levels was observed on overall (1.89, 1.30-2.73) and event-free survival (1.49, 1.06-2.08) in women. High triglyceride values were also modestly related to risk of cardiac events in diabetic men (1.28, 0.99-1.66). CONCLUSIONS: These data suggest that increased preoperative triglyceride levels predict increased late mortality and cardiac event risk in diabetic post-CABG patients, more strongly in women than in men.

OBJECTIVE To determine variables associated with glycemic and body weight responses when adding exenatide to basal insulin–treated type 2 diabetes. RESEARCH DESIGN AND METHODS Exploratory subgroup analyses based on baseline A1C, disease duration, and BMI of a 30-week study comparing exenatide twice daily to placebo, added to optimized insulin glargine (intent-to-treat analysis: 137 exenatide; 122 placebo). RESULTS Exenatide participants had greater A1C reductions compared with optimized insulin glargine alone, irrespective of baseline A1C (P < 0.001). Exenatide participants with longer diabetes duration and those with lower BMI had greater A1C reductions (P < 0.01). Exenatide participants lost more weight, regardless of baseline A1C or BMI (P < 0.05). Exenatide participants with longer diabetes duration lost the most weight (P < 0.001). CONCLUSIONS Exenatide added to optimized basal insulin was associated with improved glycemic control and weight loss, irrespective of baseline A1C, diabetes duration, and BMI. Changes were evident in modestly obese patients and in those with longer diabetes duration.

OBJECTIVE To test the hypothesis that exenatide twice daily reduces the relative incidence of cardiovascular disease (CVD) events among patients with type 2 diabetes compared with other glucose-lowering agent(s). RESEARCH DESIGN AND METHODS A retrospective database analysis was performed of the LifeLink database of medical and pharmaceutical insurance claims for June 2005 through March 2009. Patients with no history in the preceding 9 months of myocardial infarction, ischemic stroke, or coronary revascularization procedure were assigned to the exenatide-initiated or non–exenatide-initiated cohorts based on the first new prescription filled and reassigned if exenatide was prescribed or discontinued. Incident CVD events (myocardial infarction, ischemic stroke, or coronary revascularization procedure) were identified by ICD-9-CM diagnosis codes. Patient outcomes were adjusted for differences in clinical and demographic characteristics and compared using propensity score–weighted discrete time survival analysis with time-varying exposure to exenatide. RESULTS A total of 39,275 patients with type 2 diabetes were treated with exenatide twice daily, and 381,218 patients were treated with other glucose-lowering therapies. Patients who initiated exenatide were more likely to have prior ischemic heart disease, obesity, hyperlipidemia, hypertension, and/or other comorbidities at baseline. Exenatide-treated patients were less likely to have a CVD event than non–exenatide-treated patients (hazard ratio 0.81; 95% CI 0.68–0.95; P = 0.01) and lower rates of CVD-related hospitalization (0.88; 0.79–0.98; P = 0.02) and all-cause hospitalization (0.94; 0.91–0.97; P < 0.001). CONCLUSIONS Exenatide twice-daily treatment was associated with a lower risk of CVD events and hospitalizations than treatment with other glucose-lowering therapies.

OBJECTIVE Foot ulceration remains a major health problem for diabetic patients and has a major impact on the cost of diabetes treatment. We tested a hyperspectral imaging technology that quantifies cutaneous tissue hemoglobin oxygenation and generated anatomically relevant tissue oxygenation maps to assess the healing potential of diabetic foot ulcers (DFUs). RESEARCH DESIGN AND METHODS A prospective single-arm blinded study was completed in which 66 patients with type 1 and type 2 diabetes were enrolled and followed over a 24-week period. Clinical, medical, and diabetes histories were collected. Transcutaneous oxygen tension was measured at the ankles. Superficial tissue oxyhemoglobin (oxy) and deoxyhemoglobin (deoxy) were measured with hyperspectral imaging from intact tissue bordering the ulcer. A healing index derived from oxy and deoxy values was used to assess the potential for healing. RESULTS Fifty-four patients with 73 ulcers completed the study; at 24 weeks, 54 ulcers healed while 19 ulcers did not heal. When using the healing index to predict healing, the sensitivity was 80% (43 of 54), the specificity was 74% (14 of 19), and the positive predictive value was 90% (43 of 48). The sensitivity, specificity, and positive predictive values increased to 86, 88, and 96%, respectively, when removing three false-positive osteomyelitis cases and four false-negative cases due to measurements on a callus. The results indicate that cutaneous tissue oxygenation correlates with wound healing in diabetic patients. CONCLUSIONS Hyperspectral imaging of tissue oxy and deoxy may predict the healing of DFUs with high sensitivity and specificity based on information obtained from a single visit.

Historically, nutrition principles and recommendations for diabetes and related complications have been based on scientific evidence and diabetes knowledge when available and, when evidence was not available, on clinical experience and expert consensus. Often it has been difficult to discern the level of evidence used to construct the nutrition principles and recommendations. Furthermore, in clinical practice, many nutrition recommendations that have no scientific supporting evidence have been and are still being given to individuals with diabetes. To address these problems and to incorporate the research done in the past 8 years, this 2002 technical review provides principles and recommendations classified according to the level of evidence available. It reviews the evidence from randomized, controlled trials; cohort and case-controlled studies; and observational studies, which can also provide valuable evidence (1,2), and takes into account the number of studies that have provided consistent outcomes of support. In this review, nutrition principles are graded into four categories based on the available evidence: those with strong supporting evidence, those with some supporting evidence, those with limited supporting evidence and those based on expert consensus. Evidence-based nutrition recommendations attempt to translate research data and clinically applicable evidence into nutrition care. However, the best available evidence must still be moderated by individual circumstances and preferences. The goal of evidence-based recommendations is to improve the quality of clinical judgments and facilitate cost-effective care by increasing the awareness of clinicians and patients with diabetes of the evidence supporting nutrition services and the strength of that evidence, both in quality and quantity. Before 1994, the American Diabetes Association’s (ADA’s) nutrition principles and recommendations attempted to define an “ideal” nutrition prescription that would apply to everyone with diabetes (3,4,5). Although individualization was a major principle of all recommendations, it was usually done within defined …

OBJECTIVE To determine whether a forced titration of acarbose (from 50 to 300 mg three times daily) administered over a 24-week period, in conjunction with diet and insulin therapy, improves glycemic control and reduces daily insulin requirements in insulin-requiring type II diabetes. RESEARCH DESIGN AND METHODS This multicenter, randomized, double-blind, placebo-controlled trial was 36 weeks in duration. The trial consisted of a 6-week pretreatment period, a 24-week double-blind treatment period, and a 6-week post-treatment follow-up period. The primary efficacy variables were the mean change from baseline in HbA1c levels and the mean percentage change from baseline in total daily insulin dose. RESULTS Treatment with acarbose was associated with significant reductions in HbA1c levels of 0.40% (P = 0.0001) and in total daily insulin dose of 8.3% (P = 0.0015). There were also significant reductions in all plasma glucose variables measured, including a 0.9 mmol/l reduction in fasting glucose (P = 0.0440), a 2.6 mmol/l reduction in glucose Cmax (P = 0.0001) and a 270 mmol·min−1·l−1 reduction in glucose area under the curve (P = 0.0002). Although acarbose treatment was associated with a greater incidence of adverse events than was placebo treatment, primarily flatulence and diarrhea, these events did not generally prevent patients from completing the study. CONCLUSIONS The results of this study suggest that acarbose is a safe and effective adjunct to diet and insulin therapy for the management of insulin-requiring type II diabetes.

Health professionals and people with diabetes recognize nutrition therapy as one of the most challenging aspects of diabetes care and education (1). Adherence to meal planning principles requires the person with diabetes to learn specific nutrition recommendations. It may require altering previous patterns of eating and implementing new eating behaviors, which requires motivation for a healthy lifestyle and may also require participation in exercise programs. Finally, individuals must be able to evaluate the effectiveness of these lifestyle changes. Despite these challenges, nutrition is an essential component of successful diabetes management.

The interrelationship between diabetes and various vitamins and minerals is characterized by a high degree of reciprocity. Chronic uncontrolled hyperglycemia can cause significant alterations in the status of these nutrients, and conversely, some of these substances, especially those that have been characterized as micronutrients, can directly modulate glucose homeostasis (1). Differences in patient populations studied and methodological uncertainties account for the discrepancies in most reported studies. Certain subgroups of individuals with diabetes, such as elderly patients, vegans (who consume no animal products), and pregnant and lactating women, are at particular risk for deficiencies for such nutrients. Additionally, caloric restriction for obese patients and the effects of a high fiber diet and a host of drugs on the metabolism of vitamins and minerals are of concern (2,3).

Urinary C-peptide (UCP) is a noninvasive measure of integrated insulin production, and the usefulness of 24-h collections has been previously reported. Only small numbers of subjects have been studied using shorter urine collections. To see how well 4-h urine collections for C-peptide (UCP) correlate with serum immunoreactive insulin (SI) and plasma C-peptide (PCP), we studied 41 healthy subjects (19 men, 22 women) using as a stimulus a 600-kcal mixed meal and the same mixed meal after oral prednisone. UCP values correlated best with the area under the curves for SI (γ = 0.457, P < 0.001) and PCP (γ = 0.557, P < 0.001). UCP was also significantly correlated with peak SI (γ = 0.382, P < 0.001), peak PCP (γ = 0.496, P < 0.001), fasting SI (γ = 0.297, P = 0.007), and fasting PCP (γ = 0.341, P = 0.007) values. Urinary C-peptide was significantly correlated with SI and PCP concentrations in a broad range of physiologic values for SI and PCP supporting the usefulness of UCP as a simple, noninvasive measure of beta-cell function. Four-hour collections for UCP may be useful in further studies of beta-cell function.