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1.  Prediction of Diabetes Based on Baseline Metabolic Characteristics in Individuals at High Risk 
Diabetes Care  2013;36(11):3607-3612.
Individuals with impaired glucose tolerance (IGT) are at high risk for developing type 2 diabetes mellitus (T2DM). We examined which characteristics at baseline predicted the development of T2DM versus maintenance of IGT or conversion to normal glucose tolerance.
We studied 228 subjects at high risk with IGT who received treatment with placebo in ACT NOW and who underwent baseline anthropometric measures and oral glucose tolerance test (OGTT) at baseline and after a mean follow-up of 2.4 years.
In a univariate analysis, 45 of 228 (19.7%) IGT individuals developed diabetes. After adjusting for age, sex, and center, increased fasting plasma glucose, 2-h plasma glucose, ∆G0–120 during OGTT, HbA1c, adipocyte insulin resistance index, ln fasting plasma insulin, and ln ∆I0–120, as well as family history of diabetes and presence of metabolic syndrome, were associated with increased risk of diabetes. At baseline, higher insulin secretion (ln [∆I0–120/∆G0–120]) during the OGTT was associated with decreased risk of diabetes. Higher β-cell function (insulin secretion/insulin resistance or disposition index; ln [∆I0–120/∆G0–120 × Matsuda index of insulin sensitivity]; odds ratio 0.11; P < 0.0001) was the variable most closely associated with reduced risk of diabetes.
In a stepwise multiple-variable analysis, only HbA1c and β-cell function (ln insulin secretion/insulin resistance index) predicted the development of diabetes (r = 0.49; P < 0.0001).
PMCID: PMC3816921  PMID: 24062330
2.  Prevention of Diabetes With Pioglitazone in ACT NOW 
Diabetes  2013;62(11):3920-3926.
We examined the metabolic characteristics that attend the development of type 2 diabetes (T2DM) in 441 impaired glucose tolerance (IGT) subjects who participated in the ACT NOW Study and had complete end-of-study metabolic measurements. Subjects were randomized to receive pioglitazone (PGZ; 45 mg/day) or placebo and were observed for a median of 2.4 years. Indices of insulin sensitivity (Matsuda index [MI]), insulin secretion (IS)/insulin resistance (IR; ΔI0–120/ΔG0–120, ΔIS rate [ISR]0–120/ΔG0–120), and β-cell function (ΔI/ΔG × MI and ΔISR/ΔG × MI) were calculated from plasma glucose, insulin, and C-peptide concentrations during oral glucose tolerance tests at baseline and study end. Diabetes developed in 45 placebo-treated vs. 15 PGZ-treated subjects (odds ratio [OR] 0.28 [95% CI 0.15–0.49]; P < 0.0001); 48% of PGZ-treated subjects reverted to normal glucose tolerance (NGT) versus 28% of placebo-treated subjects (P < 0.005). Higher final glucose tolerance status (NGT > IGT > T2DM) was associated with improvements in insulin sensitivity (OR 0.61 [95% CI 0.54–0.80]), IS (OR 0.61 [95% CI 0.50–0.75]), and β-cell function (ln IS/IR index and ln ISR/IR index) (OR 0.26 [95% CI 0.19–0.37]; all P < 0.0001). Of the factors measured, improved β-cell function was most closely associated with final glucose tolerance status.
PMCID: PMC3806596  PMID: 23863810
3.  Canagliflozin Lowers Postprandial Glucose and Insulin by Delaying Intestinal Glucose Absorption in Addition to Increasing Urinary Glucose Excretion 
Diabetes Care  2013;36(8):2154-2161.
Canagliflozin, a sodium glucose cotransporter (SGLT) 2 inhibitor, is also a low-potency SGLT1 inhibitor. This study tested the hypothesis that intestinal canagliflozin levels postdose are sufficiently high to transiently inhibit intestinal SGLT1, thereby delaying intestinal glucose absorption.
This two-period, crossover study evaluated effects of canagliflozin on intestinal glucose absorption in 20 healthy subjects using a dual-tracer method. Placebo or canagliflozin 300 mg was given 20 min before a 600-kcal mixed-meal tolerance test. Plasma glucose, 3H-glucose, 14C-glucose, and insulin were measured frequently for 6 h to calculate rates of appearance of oral glucose (RaO) in plasma, endogenous glucose production, and glucose disposal.
Compared with placebo, canagliflozin treatment reduced postprandial plasma glucose and insulin excursions (incremental 0- to 2-h area under the curve [AUC0–2h] reductions of 35% and 43%, respectively; P < 0.001 for both), increased 0- to 6-h urinary glucose excretion (UGE0–6h, 18.2 ± 5.6 vs. <0.2 g; P < 0.001), and delayed RaO. Canagliflozin reduced AUC RaO by 31% over 0 to 1 h (geometric means, 264 vs. 381 mg/kg; P < 0.001) and by 20% over 0 to 2 h (576 vs. 723 mg/kg; P = 0.002). Over 2 to 6 h, canagliflozin increased RaO such that total AUC RaO over 0 to 6 h was <6% lower versus placebo (960 vs. 1,018 mg/kg; P = 0.003). A modest (∼10%) reduction in acetaminophen absorption was observed over the first 2 h, but this difference was not sufficient to explain the reduction in RaO. Total glucose disposal over 0 to 6 h was similar across groups.
Canagliflozin reduces postprandial plasma glucose and insulin by increasing UGE (via renal SGLT2 inhibition) and delaying RaO, likely due to intestinal SGLT1 inhibition.
PMCID: PMC3714520  PMID: 23412078
4.  Pioglitazone slows progression of atherosclerosis in prediabetes independent of changes in cardiovascular risk factors 
To determine whether changes in standard and novel risk factors during the ACT NOW trial explained the slower rate of CIMT progression with pioglitazone treatment in persons with prediabetes.
Methods and Results
CIMT was measured in 382 participants at the beginning and up to three additional times during follow-up of the ACT NOW trial. During an average follow-up of 2.3 years, the mean unadjusted annual rate of CIMT progression was significantly (P=0.01) lower with pioglitazone treatment (4.76 × 10−3 mm/year, 95% CI, 2.39 × 10−3 – 7.14 × 10−3 mm/year) compared with placebo (9.69 × 10−3 mm/year, 95% CI, 7.24 × 10−3 – 12.15 × 10−3 mm/year). High-density lipoprotein cholesterol, fasting and 2-hour glucose, HbA1c, fasting insulin, Matsuda insulin sensitivity index, adiponectin and plasminogen activator inhibitor-1 levels improved significantly with pioglitazone treatment compared with placebo (P < 0.001). However, the effect of pioglitazone on CIMT progression was not attenuated by multiple methods of adjustment for traditional, metabolic and inflammatory risk factors and concomitant medications, and was independent of changes in risk factors during pioglitazone treatment.
Pioglitazone slowed progression of CIMT, independent of improvement in hyperglycemia, insulin resistance, dyslipidemia and systemic inflammation in prediabetes. These results suggest a possible direct vascular benefit of pioglitazone.
PMCID: PMC3908828  PMID: 23175674
Carotid atherosclerosis progression; Impaired glucose tolerance; Insulin resistance; Inflammation; Pioglitazone
5.  Comparison of Longer-Term Safety and Effectiveness of Four Atypical Antipsychotics in Patients over Age 40: A Trial Using Equipoise-Stratified Randomization 
To compare longer-term safety and effectiveness of the four most commonly used atypical antipsychotics (AAPs: aripiprazole, olanzapine, quetiapine, and risperidone) in 332 patients, aged >40 years, having psychosis associated with schizophrenia, mood disorders, PTSD, or dementia, diagnosed using DSM-IV-TR criteria.
We used Equipoise-Stratified Randomization (a hybrid of Complete Randomization and Clinician’s Choice Methods) that allowed patients or their treating psychiatrists to exclude one or two of the study AAPs, because of past experience or anticipated risk. Patients were followed for up to two years, with assessments at baseline, 6 weeks, 12 weeks, and every 12 weeks thereafter. Medications were administered employing open-label design and flexible dosages, but with blind raters.
Outcome Measures
(1) Primary metabolic markers (body mass index or BMI, blood pressure, fasting blood glucose, LDL cholesterol, HDL cholesterol, and triglycerides), (2) % patients who stay on the randomly assigned AAP for at least 6 months, (3) Psychopathology, (4) % patients who develop Metabolic Syndrome, and (5) % patients who develop serious and non-serious adverse events.
Because of high incidence of serious adverse events, quetiapine was discontinued midway through the trial. There were significant differences among patients willing to be randomized to different AAPs, suggesting that treating clinicians tended to exclude olanzapine and prefer aripiprazole as one of the possible choices in patients with metabolic problems. Yet, the AAP groups did not differ in longitudinal changes in metabolic parameters or on most other outcome measures. Overall results suggested a high discontinuation rate (median duration 26 weeks prior to discontinuation), lack of significant improvement in psychopathology, and high cumulative incidence of metabolic syndrome (36.5% in one year) and of serious (23.7%) and non-serious (50.8%) adverse events for all AAPs in the study.
Employing a study design that closely mimicked clinical practice, we found a lack of effectiveness and a high incidence of side effects with four commonly prescribed AAPs across diagnostic groups in patients over age 40, with relatively few differences among the drugs. Caution in the use of these drugs is warranted in middle-aged and older patients.
PMCID: PMC3600635  PMID: 23218100
Antipsychotic; Metabolic Syndrome; Schizophrenia; Dementia; Mood disorder; Equipoise-Stratified Randomization
6.  Remogliflozin Etabonate, a Selective Inhibitor of the Sodium-Glucose Transporter 2, Improves Serum Glucose Profiles in Type 1 Diabetes 
Diabetes Care  2012;35(11):2198-2200.
Remogliflozin etabonate (RE), an inhibitor of the sodium-glucose transporter 2, improves glucose profiles in type 2 diabetes. This study assessed safety, tolerability, pharmacokinetics, and pharmacodynamics of RE in subjects with type 1 diabetes.
Ten subjects managed with continuous subcutaneous insulin infusion were enrolled. In addition to basal insulin, subjects received five randomized treatments: placebo, prandial insulin, 50 mg RE, 150 mg RE, and mg RE 500.
Adverse events and incidence of hypoglycemia with RE did not differ from placebo and prandial insulin groups. RE significantly increased urine glucose excretion and reduced the rise in plasma glucose concentration after oral glucose. RE reduced incremental adjusted weighted mean glucose (0–4 h) values by 42–49 mg/dL and mean glucose (0–10 h) by 52–69 mg/dL.
RE can be safely administered with insulin in type 1 diabetes and reduces plasma glucose concentrations compared with placebo.
PMCID: PMC3476920  PMID: 23011728
7.  Increased Framingham 10-year risk of Coronary Heart Disease in middle aged and older patients with psychotic symptoms 
Schizophrenia research  2010;125(2-3):295-299.
The Framingham 10-risk of coronary heart disease (CHD) has been a widely studied estimate of cardiovascular risk in the general population. However, few studies have compared the relative risk of developing CHD in antipsychotic-treated patients with different psychiatric disorders, especially in older patients with psychotic symptoms. In this study, we compared the 10-year risk of developing CHD among middle-aged and older patients with psychotic symptoms to that in the general population.
We analyzed baseline data from a study examining metabolic and cardiovascular effects of atypical antipsychotics in patients over age 40 with psychotic symptoms. After excluding patients with prior history of CHD and stroke, 179 subjects were included in this study. Among them, 68 had a diagnosis of schizophrenia, 42 mood disorder, 38 dementia, and 31 PTSD. Clinical evaluations included medical and pharmacologic treatment history, physical examination, and clinical labs for metabolic profiles. Using the Framingham 10–year risk of developing CHD based on the Framingham Heart Study (FHS), we calculated the risk CHD risk for each patient, and then compared relative risk in each psychiatric diagnosis to the risks reported in the FHS.
The mean age of entire sample was 63 (range 40–94) years, 68% were men. The Framingham 10-year risk of CHD was increased by 79% in schizophrenia, 72% in PTSD, 61% in mood disorder with psychosis, and 11% in dementia relative to the risk in general population from the FHS.
In this sample of middle-aged and older patients with psychotic symptoms, we found a significantly increased 10-year risk of CHD relative to the estimated risk from FHS, with the greatest increased risk for patients with schizophrenia and PTSD. Development of optimally tailored prevention and intervention efforts to decrease different risk components in these patients could be an important step to help decrease the risks of CHD and overall mortality in this vulnerable population.
PMCID: PMC3031775  PMID: 21093219
Framingham 10-year CHD risk; Psychotic disorders; middle aged and older patients
8.  Intensive Glucose-Lowering Therapy Reduces Cardiovascular Disease Events in Veterans Affairs Diabetes Trial Participants With Lower Calcified Coronary Atherosclerosis 
Diabetes  2009;58(11):2642-2648.
This study investigated the hypothesis that baseline calcified coronary atherosclerosis may determine cardiovascular disease events in response to intensive glycemic control within the Veterans Affairs Diabetes Trial (VADT).
At baseline, 301 type 2 diabetic participants in the VADT, a randomized trial comparing the effects of intensive versus standard glucose lowering on cardiovascular events, had baseline coronary atherosclerosis assessed by coronary artery calcium (CAC) measured by computed tomography. Participants were followed over the 7.5-year study for development of cardiovascular end points.
During a median follow-up duration of 5.2 years, 89 cardiovascular events occurred. Although intensive glucose-lowering therapy did not significantly reduce cardiovascular events in the substudy cohort as a whole, there was evidence that the response was modified by baseline CAC, as indicated by significant P values for treatment by log(CAC + 1) interaction terms in unadjusted and multivariable-adjusted models (0.01 and 0.03, respectively). Multivariable-adjusted hazard ratios (HRs) for the effect of treatment indicated a progressive diminution of benefit with increasing CAC. Subgroup analyses were also conducted for clinically relevant CAC categories: those above and below an Agatston score of 100. Among those randomized to intensive treatment, for the subgroup with CAC >100, 11 of 62 individuals had events, while only 1 of 52 individuals with CAC ≤100 had an event. The multivariable HR for intensive treatment for those with CAC >100 was 0.74 (95% CI 0.46–1.20; P = 0.21), while for the subgroup with CAC ≤100, the corresponding HR was 0.08 (0.008–0.77; P = 0.03), with event rates of 39 and 4 per 1,000 person-years, respectively.
These data indicate that intensive glucose lowering reduces cardiovascular events in those with less extensive calcified coronary atherosclerosis.
PMCID: PMC2768182  PMID: 19651816
9.  Actos Now for the prevention of diabetes (ACT NOW) study 
Impaired glucose tolerance (IGT) is a prediabetic state. If IGT can be prevented from progressing to overt diabetes, hyperglycemia-related complications can be avoided. The purpose of the present study was to examine whether pioglitazone (ACTOS®) can prevent progression of IGT to type 2 diabetes mellitus (T2DM) in a prospective randomized, double blind, placebo controlled trial.
602 IGT subjects were identified with OGTT (2-hour plasma glucose = 140–199 mg/dl). In addition, IGT subjects were required to have FPG = 95–125 mg/dl and at least one other high risk characteristic. Prior to randomization all subjects had measurement of ankle-arm blood pressure, systolic/diastolic blood pressure, HbA1C, lipid profile and a subset had frequently sampled intravenous glucose tolerance test (FSIVGTT), DEXA, and ultrasound determination of carotid intima-media thickness (IMT). Following this, subjects were randomized to receive pioglitazone (45 mg/day) or placebo, and returned every 2–3 months for FPG determination and annually for OGTT. Repeat carotid IMT measurement was performed at 18 months and study end. Recruitment took place over 24 months, and subjects were followed for an additional 24 months. At study end (48 months) or at time of diagnosis of diabetes the OGTT, FSIVGTT, DEXA, carotid IMT, and all other measurements were repeated.
Primary endpoint is conversion of IGT to T2DM based upon FPG ≥ 126 or 2-hour PG ≥ 200 mg/dl. Secondary endpoints include whether pioglitazone can: (i) improve glycemic control (ii) enhance insulin sensitivity, (iii) augment beta cell function, (iv) improve risk factors for cardiovascular disease, (v) cause regression/slow progression of carotid IMT, (vi) revert newly diagnosed diabetes to normal glucose tolerance.
ACT NOW is designed to determine if pioglitazone can prevent/delay progression to diabetes in high risk IGT subjects, and to define the mechanisms (improved insulin sensitivity and/or enhanced beta cell function) via which pioglitazone exerts its beneficial effect on glucose metabolism to prevent/delay onset of T2DM.
Trial Registration
clinical identifier: NCT00220961
PMCID: PMC2725044  PMID: 19640291
10.  Impact of Atypical Antipsychotic Therapy on Leptin, Ghrelin, and Adiponectin 
Schizophrenia research  2008;100(1-3):70-85.
Many adverse effects of atypical antipsychotic treatment are associated with antagonism of monoamine receptors; however, data indicate that important metabolic effects, such as hypertriglyceridemia and impairment in glucose/insulin homeostasis, may not be related to these mechanisms, leading investigators to explore alternative hypotheses. Promising candidates include a possible impact of antipsychotics on peptide hormonal regulators of metabolic control such as leptin, ghrelin, and adiponectin. The purpose of this review is to summarize recent data on changes in these hormones during atypical antipsychotic treatment.
A Medline search was performed for papers published from January 1999 to January 2007 using key words antipsychotic, atypical antipsychotic, and individual atypical antipsychotic drug names cross-referenced with leptin, ghrelin, and adiponectin.
The bulk of the published work focused on changes in body weight and serum leptin, with far less data on ghrelin, and adiponectin, and non-weight metabolic changes. Leptin changes were directly related to a medication’s weight gain liability, with no added antipsychotic effects on leptin signaling. Conflicting results emerged for the other markers, but all three long-term studies on ghrelin showed increased levels in patients on atypical antipsychotics with weight gain liabilities.
Leptin increases during antipsychotic treatment are a result of weight gain rather than a direct impact of atypical antipsychotics on leptin physiology. Preliminary long-term data show increased ghrelin levels, but this finding must be replicated. The association with antipsychotic effects on glucose and lipid metabolism and these hormones remains virtually unstudied. Future research should indicate whether ghrelin and other peptide hormones may be useful predictors of weight gain or metabolic changes in patients on antipsychotics.
PMCID: PMC2699769  PMID: 18206351
11.  Significant Insulin Dose Errors May Occur if Blood Glucose Results Are Obtained from Miscoded Meters 
The objective of this study was to determine inaccuracies of miscoded blood glucose (BG) meters and potential errors in insulin dose based on values from these meters.
Research Design
Fasting diabetic subjects at three clinical centers participated in a 2-hour meal tolerance test. At various times subjects' blood was tested on five BG meters and on a Yellow Springs Instruments laboratory glucose analyzer. Some meters were purposely miscoded. Using the BG values from these meters, along with three insulin dose algorithms, Monte Carlo simulations were conducted to generate ideal and simulated-meter glucose values and subsequent probability of insulin dose errors based on normal and empirical distribution assumptions.
Maximal median percentage biases of miscoded meters were +29% and −37%, while maximal median percentage biases of correctly coded meters were only +0.64% and −10.45% (p = 0.000, χ2 test, df = 1). Using the low-dose algorithm and the normal distribution assumption, the combined data showed that the probability of insulin error of ±1U, ±2, ±3, ±4, and ±5U for miscoded meters could be as high as 49.6, 50.0, 22.3, 1.4, and 0.04%, respectively. This is compared to manually, correctly coded meters where the probability of error of ±1, ±2, and ±3U could be as high as 44.6, 7.1, and 0.49%, respectively. There was no instance of a ±4 or ±5U insulin dose error with a manually, correctly coded meter. For autocoded meters, the probability of ±1 and ±2U could be as high as 35.4 and 1.4%, respectively. For autocoded meters there were no calculated insulin dose errors above ±2U. The probability of insulin misdosing with either manually, correctly coded or autocoded meters was significantly lower than that with miscoded meters. Results using empirical distributions showed similar trends of insulin dose errors.
Blood glucose meter coding errors may result in significant insulin dosing errors. To avoid error, patients should be instructed to code their meters correctly or be advised to use an autocoded meter that showed superior performance over manually, correctly coded meters in this study.
PMCID: PMC2771463  PMID: 19888408
autocode; autocoded blood glucose meter; blood glucose; blood glucose meter; insulin dose error; manual code; miscoded meter; Monte Carlo simulation; self-monitoring of blood glucose; user error
12.  Evolution of Exenatide as a Diabetes Therapeutic 
Current Diabetes Reviews  2013;9(2):161-193.
Type 2 diabetes (T2DM) is a disease of epidemic proportion associated with significant morbidity and excess mortality. Optimal glucose control reduces the risk of microvascular and possibly macrovascular complications due to diabetes. However, glycemic control is rarely optimal and several therapeutic interventions for the treatment of diabetes cause hypoglycemia and weight gain; some may exacerbate cardiovascular risk. Exenatide (synthetic exendin-4) is a glucagon-like peptide-1 receptor (GLP-1R) agonist developed as a first-in-class diabetes therapy. This review presents an overview of the evolution of exenatide as a T2DM treatment, beginning with the seminal preclinical discoveries and continuing through to clinical pharmacology investigations and phase 3 clinical trials. In patients with T2DM, exenatide enhanced glucose-dependent insulin secretion, suppressed inappropriately elevated glucagon secretion, slowed gastric emptying, and enhanced satiety. In controlled phase 3 clinical trials ranging from 12 to 52 weeks, 10-mcg exenatide twice daily (ExBID) reduced mean HbA1c by -0.8% to -1.7% as monotherapy or in combination with metformin (MET), sulfonylureas (SFU), and/or thiazolidinediones (TZD); with mean weight losses of -1.2 kg to -8.0 kg. In controlled phase 3 trials ranging from 24 to 30 weeks, a 2-mg once-weekly exenatide formulation (ExQW) reduced mean HbA1c by -1.3% to -1.9%, with mean weight reductions of -2.3 to -3.7 kg. Exenatide was generally well-tolerated. The most common side effects were gastrointestinal in nature, mild, and transient. Nausea was the most prevalent adverse event. The incidence of hypoglycemia was generally low. By building upon early observations exenatide was successfully developed into an effective diabetes therapy.
PMCID: PMC3664512  PMID: 23256660
Diabetes mellitus; Exenatide; Exendin-4; GLP-1 receptor agonist.

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