Thiazolidinediones: the Forgotten Diabetes Medications.

PURPOSE OF REVIEW: Thiazolidinediones (TZDs) are the only pharmacologic agents that specifically treat insulin resistance. The beneficial effects of TZDs on the cardiovascular risk factors associated with insulin resistance have been well documented. TZD use has been limited because of concern about safety issues and side effects. RECENT FINDINGS: Recent studies indicate that cardiovascular toxicity with rosiglitazone and increase in bladder cancer with pioglitazone are no longer significant issues. There are new data which show that pioglitazone treatment reduces myocardial infarctions and ischemic strokes. New data concerning TZD-mediated edema, congestive heart failure, and bone fractures improves the clinician's ability to select patients that will have minimal significant side effects. Thiazolidinediones are now generic and less costly than pharmaceutical company-promoted therapies. Better understanding of the side effects coupled with clear benefits on the components of the insulin resistance syndrome should promote TZD use in treating patients with type 2 diabetes.

Ketosis-Prone Diabetes (Flatbush Diabetes): an Emerging Worldwide Clinically Important Entity.

PURPOSE OF REVIEW: Ketosis-prone diabetes or Flatbush diabetes has been widely recognized as a clinical entity since 1984. Most of the early clinical studies focused on African American or Afro-Caribbean individuals. It is now being recognized as an important clinical entity in sub-Saharan Africans, Asian and Indian populations, and Hispanic populations. Major questions remain as to its pathogenesis and whether it is a unique type of diabetes or a subset of more severe type 2 diabetes with greater loss of insulin action in target tissues. This review summarizes the main clinical and mechanistic studies to improve the understanding of ketosis-prone (Flatbush) diabetes. RECENT FINDINGS: Little data are available on the magnitude of KPD in the different susceptible populations. It is relatively common in black populations. KPD is defined as a syndrome in which diabetes commences with ketoacidosis in individuals who are GAD and anti-islet cell antibody negative and have no known precipitating causes. The patients present during middle age, are overweight or mildly obese, and in many reports are more likely to be male. After intensive initial insulin therapy, many patients become insulin independent and can be well controlled on diet alone or diet plus oral medications. The clinical course of KPD is like that of patients with type 2 diabetes rather than that of type 1 diabetes. Little differences are found in the clinical characteristics and clinical outcomes between patients presenting with KPD and those presenting with severe hyperglycemia with no ketoacidosis. The mechanisms responsible for the development of ketosis-prone diabetes as well its remission remain unknown.

Interventional treatment of obesity and diabetes: An interim report on gastric electrical stimulation.

Gastric electrical stimulation has been applied to treat human obesity since 1995. Dilatation of the stomach causes a series of neural reflexes which result in satiation and satiety. In non-obese individuals food ingestion is limited in part by this mechanism. In obese individuals, satiation and satiety are defective and unable to limit energy intake and prevent excessive weight gain. Several gastric electrical stimulatory (GES) devices have been developed, tested in clinical trials and even approved for the treatment of obesity. The design and clinical utility of three devices (Transend®, Maestro® and DIAMOND®) that have been extensively studied are presented as well as that of a new device (abiliti®) which is in early development. The Transcend®, a low energy GES device, showed promising results in open label studies but failed to show a difference from placebo in decreasing weight in obese subjects. The results of the clinical trials in treating obese subjects with the Maestro®, a vagal nerve stimulator, were sufficient to gain approval for marketing the device. The DIAMOND®, a multi-electrode GES device, has been used to treat type 2 diabetes and an associated benefit is to reduce body weight and lower systolic blood pressure.

Metabolic surgery for type 2 diabetes: appraisal of clinical evidence and review of randomized controlled clinical trials comparing surgery with medical therapy.

Bariatric surgical procedures were originally developed to treat morbid obesity where their benefits certainly outweigh their potential side effects. Although they are very beneficial in improving metabolic control in type 2 diabetes, there are many medical treatments that are also effective. The role of bariatric surgery as primary therapy for type 2 diabetes depends on whether the benefit exceeds the surgical and nutritional complications, which are significant. The ultimate role for bariatric surgery in treating type 2 diabetes can only be determined by large, long-term randomized clinical trials which compare clinical outcomes of bariatric surgery with those of current intensive medical treatment. The four reported small, mostly 1-year trials have shown superior glycemic control by surgery as compared with medical treatment, but at the expense of significant surgical complications and unknown nutritional liability. They show that future trials will have to be much larger and last for at least 5-10 years.

Efficacy and safety of Tregopil, a novel, ultra-rapid acting oral prandial insulin analog, as part of a basal-bolus regimen in type 2 diabetes: a randomized, active-controlled phase 2/3 study.

BACKGROUND: Efficacy and safety of ultra-rapid acting oral prandial insulin Tregopil was compared with insulin aspart (IAsp) in patients with type 2 diabetes (T2D) on insulin glargine and metformin. RESEARCH DESIGN AND METHODS: In this open-label, active-controlled trial, patients with T2D, HbA1c ≥7%-≤9% and 2-h postprandial glucose (PPG) ≥180 mg/dL were randomized 1:1:1 to Tregopil (30 mg, n = 30; 45 mg, n = 31) and IAsp, n = 30. Primary outcome was change from baseline (CFB) in HbA1c at week 24. Secondary outcomes included PPG excursion (PPGE) and PPG assessed from standardized test meal (STM) and 9-point self-monitored blood glucose. RESULTS: The observed mean HbA1c did not improve at week 24 in Tregopil groups (30 mg [0.15%], 45 mg [0.22%] vs. a reduction in IAsp group [-0.77%]). Combined Tregopil group showed better 1-h PPGE control versus IAsp following STM (CFB, estimated treatment difference, 95% CI, -45.33 mg/dL [-71.91, -18.75], p = 0.001) and 1-h PPG trended toward better control. Tregopil showed lower PPGE at 15 min versus IAsp. Clinically significant hypoglycemia was lower with Tregopil versus. IAsp (rate ratio: 0.69). CONCLUSIONS: Tregopil demonstrated an ultrafast, short-duration prandial profile with good safety. While Tregopil's early postprandial effects were comparable to IAsp, its late postprandial effects were inferior. TRIAL REGISTRATION: The trial is registered at ClinicalTrials.gov (CT.gov identifier: NCT03430856).

Long-term changes in weight and plasma lipids during maintenance treatment with ziprasidone.

To measure the long-term changes in weight and plasma lipids after switching antipsychotic treatment to ziprasidone, three 52-week, open-label extension studies of ziprasidone in outpatients (N=185) with schizophrenia or schizoaffective disorder successfully completing one of three, 6-week switch studies were carried out. Pre-switch treatment consisted of risperidone (n=43), olanzapine (n=71), or conventional antipsychotic agents (n=71). The maximum length of exposure to ziprasidone was 58 weeks. Nonfasting total cholesterol and triglyceride levels were obtained at baseline and at weeks 6, 19, 32, 45, and 58. Weight was measured at baseline and during each follow-up visit; height was recorded at baseline for the purpose of body mass index (BMI) calculation. Efficacy measures included the Positive and Negative Syndrome Scale and Clinical Global Impression-Severity scale which were obtained at baseline and major follow-up points. Clinically significant sustained improvements in weight, BMI, total cholesterol, and triglyceride levels were observed among patients switched to ziprasidone from risperidone or olanzapine. Switching from conventional antipsychotics was not associated with significant changes in weight and lipid parameters. Mean reductions in weight from baseline to study endpoint were 9.8 kg (p<0.001) and 6.9 kg (p<0.005) for patients previously treated with olanzapine and risperidone, respectively. These findings demonstrate that switching from risperidone or olanzapine to ziprasidone is associated with sustained, clinically significant improvements in weight and plasma lipids.

Gastric Contractility Modulation - a novel method for the treatment of type 2 diabetes mellitus and obesity.

Because the majority of antidiabetic medications are of limited efficacy and patient compliance with treatment is usually poor, new therapies are still being searched for. In the review a newly developed system for treatment of subjects with type 2 diabetes and concomitant overweight/obesity is described. The system consists of an implantable pulse generator that delivers electrical stimuli through leads implanted in the sero-muscular layer of the stomach. The device recognises and automatically modulates natural electrical activity of the stomach during meals, strengthening gastric contractility. This increase in the force of contractions enhances vagal afferent activity. Modulated signals are transmitted to the regulatory centres in the brain in order to provoke an early response of the gut typical of a full meal. Clinical trials performed to date show that the system improves glycaemic control with minimal patient compliance needed and with added benefits of body weight loss, a decrease in blood pressure, and favourable changes in the lipid profile. The system is safe, well-tolerated, with a low risk of hypoglycaemia, and will probably become an alternative to the use of incretins or to bariatric surgery in obese patients who are unwilling to undergo a major and anatomically irreversible operation.

Therapeutic options in development for management of diabetes: pharmacologic agents and new technologies.

OBJECTIVE: To review new pharmacologic therapies and technologies relevant to the management of diabetes and its complications. METHODS: New treatment options for diabetes, made available through research efforts during the past 2 decades, are discussed. RESULTS: Several new drugs and drug classes for the management of diabetes are under development, including the incretin mimetic agents (exenatide, dipeptidyl peptidase 4 inhibitors, and glucagon-like peptide 1 analogues), the amylin analogue pramlintide, the cannabinoid-1 receptor antagonist rimonabant, the mixed peroxisome proliferator-activated receptor agonists muraglitazar and tesaglitazar, the inhaled insulin preparation Exubera, and the insulin analogues (insulin glulisine and insulin detemir). CONCLUSION: New drugs and technologic advances being made available will help achieve the goals of treating patients with diabetes to all the appropriate metabolic targets. Many other agents that act on fundamental abnormalities such as energy imbalance, inflammation, and vascular biologic conditions are in very early stages of development but are likely to become available during the next 5 to 10 years.

Evaluation of liver function in type 2 diabetic patients during clinical trials: evidence that rosiglitazone does not cause hepatic dysfunction.

OBJECTIVE: Troglitazone treatment has been associated with idiosyncratic hepatic reaction leading to hepatic failure and death in some patients. This raises questions regarding whether all thiazolidinediones or peroxisomal proliferator-activated receptor-gamma (PPAR-gamma) agonists are hepatotoxic and whether data from clinical trials are adequate to detect a signal of potentially serious drug-related hepatotoxicity. The purpose of this study was to assess whether the idiosyncratic liver toxicity reported with troglitazone is molecule-specific or a thiazolidinedione class effect, based on liver enzyme data collected prospectively during phase 2/3 clinical trials with rosiglitazone, a new, potent, and specific member of the thiazolidinedione class. RESEARCH DESIGN AND METHODS: This is an analysis of liver function in type 2 diabetic patients at baseline and serially in 13 double-blind, 2 open-label active-controlled, and 7 open-label extension studies of rosiglitazone treatment conducted in outpatient centers throughout North America and Europe. The study comprised > 6,000 patients aged 30-80 years with type 2 diabetes. Patients underwent baseline liver function studies and were excluded from clinical trials if they had an alanine aminotransferase (ALT), aspartate aminotransferase (AST), or alkaline phosphatase value 2.5 times greater than the upper limit of the reference range. The main outcome measures were liver enzyme levels, which were assessed at screening, at baseline, and every 4 weeks for the first 3 months of treatment and at 6- to 12-week intervals thereafter. Patients with at least one on-therapy ALT value >3 times the upper limit of the reference range were identified, and their case records examined in detail. RESULTS: At baseline, 5.6% of the patients with type 2 diabetes (mean HbA(1c) 8.5-9.0%) had serum ALT values between 1.0 and 2.5 times the upper limit of the reference range. On antidiabetic therapy, most of those patients ( approximately 83%) had a decrease in ALT values, many into the normal range. The percentages of all patients with an on-therapy ALT value >3 times the upper limit of the reference range during double-blind and open-label treatment were as follows: rosiglitazone-treated 0.32%, placebo-treated 0.17%, and sulfonylurea-, metformin-, or insulin-treated 0.40%. The respective rates of ALT values >3 times the upper limit of the reference range per 100 person-years of exposure were 0.29, 0.59, and 0.64. CONCLUSIONS: No evidence of hepatotoxic effects was observed in studies that involved 5,006 patients taking rosiglitazone as monotherapy or combination therapy for 5,508 person-years. This is in keeping with hepatic data from clinical trials of another member of the class, pioglitazone, and in contrast to the clear evidence of hepatotoxic effects observed during the troglitazone clinical trial program. These findings suggest that the idiosyncratic liver toxicity observed with troglitazone is unlikely to be a thiazolidinedione or a PPAR-gamma agonist class effect. Poorly controlled patients with type 2 diabetes may have moderate elevations of serum ALT that will decrease with improved glycemic control during treatment with rosiglitazone or other antihyperglycemic agents.

Gastric electrical stimulation treatment of type 2 diabetes: effects of implantation versus meal-mediated stimulation. A randomized blinded cross-over trial.

Gastric electrical stimulation with the implanted DIAMOND device has been shown to improve glycemic control and decrease weight and systolic blood pressure in patients with type 2 diabetes inadequately controlled with oral antidiabetic agents. The objective of this study was to determine if device implantation alone (placebo effect) contributes to the long-term metabolic benefits of DIAMOND(®) meal-mediated gastric electrical stimulation in patients with type 2 diabetes. The study was a 48 week randomized, blinded, cross-over trial in university centers comparing glycemic improvement of DIAMOND(®) implanted patients with type 2 diabetic with no activation of the electrical stimulation (placebo) versus meal-mediated activation of the electrical signal. The endpoint was improvement in glycemic control (HbA1c) from baseline to 24 and 48 weeks. In period 1 (0-24 weeks), equal improvement in HbA1c occurred independent of whether the meal-mediated electrical stimulation was turned on or left off (HbA1c -0.80% and -0.85% [-8.8 and -9.0 mmol/mol]). The device placebo improvement proved to be transient as it was lost in period 2 (25-48 weeks). With electrical stimulation turned off, HbA1c returned toward baseline values (8.06 compared to 8.32%; 64.2 to 67.4 mmol/mol, P = 0.465). In contrast, turning the electrical stimulation on in period 2 sustained the decrease in HbA1c from baseline (-0.93%, -10.1mmol/mol, P = 0.001) observed in period 1. The results indicate that implantation of the DIAMOND device causes a transient improvement in HbA1c which is not sustained beyond 24 weeks. Meal-mediated electrical stimulation accounts for the significant improvement in HbA1c beyond 24 weeks.

A pilot study to compare meal-triggered gastric electrical stimulation and insulin treatment in Chinese obese type 2 diabetes.

BACKGROUND: Gastrointestinal electromodulation therapy is a novel alternative for achieving diabetes control without traditional bariatric surgery. We compared the efficacy of a meal-initiated implantable gastric contractility modulation (GCM) device with that of insulin therapy in obese Chinese type 2 diabetes (T2D) patients, for whom oral antidiabetes drugs (OADs) had failed. PATIENTS AND METHODS: Sixteen obese (body mass index, 27.5-40.0 kg/m(2)) T2D patients with a glycated hemoglobin (HbA1c) level of >7.5% on maximal doses of two or more OADs were offered either insulin therapy (n=8) or laparoscopic implantation of a GCM (n=8). We compared changes in body weight, waist circumference (WC), and HbA1c level 1 year after surgery. RESULTS: The GCM and insulin groups had similar baseline body weight and HbA1c. At 12 months, body weight (-3.2±5.2 kg, P=0.043) and WC (-3.8±4.5 cm, P=0.021) fell in the GCM group but not in the insulin group (P<0.05 for between-group difference). At 6 and 12 months, the HbA1c level fell by 1.6±1.1% and 0.9±1.6% (P=0.011), compared with 0.6±0.3% and 0.6±0.3% (P=0.08) for the insulin group (P=0.15 for between-group difference). The mean 24-h systolic blood pressure (BP) fell by 4.5±1.0 mm Hg in the GCM group (P=0.017) but not in the insulin group. The GCM group required fewer antidiabetes medications (P<0.05) and BP-lowering drugs (P<0.05) than the insulin group. A subgroup analysis showed that patients with a triglyceride level of <1.7 mmol/L had a tendency toward a lower HbA1c level (P=0.090) compared with the controls. CONCLUSIONS: In obese T2D patients for whom OADs had failed, GCM implantation was a well-tolerated alternative to insulin therapy, with a low triglyceride level as a possible predictor for glycemic response.

Rationale for and role of thiazolidinediones in type 2 diabetes mellitus.

Several classes of antihyperglycemic agents are available for the treatment of patients with type 2 diabetes. These agents, including thiazolidinediones, biguanides, insulin secretagogues, alpha-glucosidase inhibitors, and insulin, offer differing mechanisms of actions and can be used either alone or in combination. The thiazolidinediones are a newer class of oral antidiabetic agents that improve glycemic control and may preserve beta-cell function. Clinical trial data suggest that patients with type 2 diabetes experience progressive deterioration of beta-cell function. By decreasing insulin resistance, thiazolidinediones may preserve beta-cell function, and patients may experience prolonged glycemic control. The thiazolidinediones also exert beneficial effects on dyslipidemia, endothelial function, coagulation, and blood pressure. By improving these components of the metabolic syndrome, thiazolidinediones may reduce the incidence of both microvascular and macrovascular complications. This article provides an overview of the role of thiazolidinediones in the treatment of type 2 diabetes.

Treatment of insulin resistance in diabetes mellitus.

Insulin resistance is a condition in which the glycemic response to insulin is less than normal. The change in insulin sensitivity leads to several sets of responses. One set effects the beta cell and leads to its accelerated destruction and the development of diabetes mellitus. The other set generates a series of nontraditional cardiovascular risk factors that result in accelerated atherosclerosis. Both of these sets of responses may have impacts on other tissues such as the nervous system. Insulin resistance is probably the result of increased visceral adiposity with increased release of free fatty acids and cytokines and a decreased release of adiponectin. Treatment of insulin resistance and its associated abnormalities can be achieved by lifestyle modification which results in weight loss, by drugs that reverse the abnormal adipocyte effects, by drugs that improve insulin sensitivity at the level of the liver and by anti-inflammatory agents that block activation of the nuclear factor kappa B cascade.

Oral antidiabetic agents: 2004.

The appropriate management of patients with type 2 diabetes presents many challenges to health care providers. The first several years of type 2 diabetes are likely to be unrecognized and untreated. The pathophysiology of type 2 diabetes dictates that treatment of insulin resistance should be an early and central focus for every therapeutic program. The pharmacologic tools currently available are capable of allowing most patients with type 2 diabetes to achieve good metabolic control. Implementation of early combination therapy is essential if glycemic targets are to be met.

Treating hyperglycemia in type 2 diabetes: new goals and strategies.

To achieve glycemic goals in type 2 diabetes, one must usually use combinations of oral agents or oral agents plus insulin. This paper discusses the metabolic derangements of type 2 diabetes, the different classes of antihyperglycemic drugs, and strategies for using these drugs rationally.

The relationship of obesity to the metabolic syndrome.

Obese patients with the metabolic syndrome generally have a visceral (apple-shaped) fat distribution and are at an increased risk of macrovascular disease, while those with peripheral (pear-shaped) obesity tend not to have metabolic abnormalities and are at less risk. This difference appears to be related to the differing metabolic functions (and secretory products) of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT), as well as the fact that VAT drains directly into the liver. Thus, it appears that increased VAT, but not SAT, is associated with both hepatic and peripheral biochemical abnormalities leading to insulin resistance and the associated metabolic syndrome. Insulin resistance is associated with VAT products, such as free fatty acids and their metabolites, as well as cytokines, such as tumour necrosis factor alpha (TNF-alpha). These factors may activate components of the inflammatory pathway such as nuclear factor kappa-B (NFkappaB), and inhibit insulin signalling. Insulin resistance is further associated with decreased levels of another tissue product, adiponectin. The incidence and prevalence of obesity is increasing at an unprecedented rate. The classic treatment of obesity is weight loss via lifestyle modification. However, prevention of obesity comorbidity can also be achieved by modifying the mechanisms by which obesity causes these comorbid conditions. For instance, it is now known that the peroxisome proliferator-activated receptor (PPAR) family of transcriptional regulators are crucial in regulating adipose tissue development and metabolism; this helps explain why compounds with PPARgamma agonist activity, e.g. thiazolidinediones, increase insulin action through their effects in regulating adipose tissue metabolism.

The DIAMOND system in the treatment of type 2 diabetes mellitus in an obese patient.

Obesity and type 2 diabetes mellitus have reached epidemic proportions worldwide. As the majority of antidiabetic medications are of limited efficacy and patient adherence to long-term therapy is one of the main limiting factors of effective blood glucose and body weight control, new therapies are still looked for. The DIAMOND system seems to be one of the most promising among them. This system recognizes natural electrical activity of the stomach and automatically applies electrical stimulation treatment during/after eating with subsequent modulation of signals transmitted to the regulatory centers in the brain in order to provoke an early response of the gut typical of a full meal. We present the case of a 47-year-old obese woman with type 2 diabetes. During treatment with this system, serum glucose and hemoglobin A1c levels significantly decreased. Body weight loss and waist circumference reduction were observed. Additionally, beneficial effect on lipid profile was found.