Cardiovascular effects of dipeptidyl peptidase-4 inhibitors: from risk factors to clinical outcomes

Dipeptidyl peptidase-4 (DPP-4) inhibitors (gliptins) are oral incretin-based glucose-lowering agents with proven efficacy and safety in the management of type 2 diabetes mellitus (T2DM). In addition, preclinical data and mechanistic studies suggest a possible additional non-glycemic beneficial action on blood vessels and the heart, via both glucagon-like peptide-1-dependent and glucagon-like peptide-1-independent effects. As a matter of fact, DPP-4 inhibitors improve several cardiovascular risk factors: they improve glucose control (mainly by reducing the risk of postprandial hyperglycemia) and are weight neutral; may lower blood pressure somewhat; improve postprandial (and even fasting) lipemia; reduce inflammatory markers; diminish oxidative stress; improve endothelial function; and reduce platelet aggregation in patients with T2DM. In addition, positive effects on the myocardium have been described in patients with ischemic heart disease. Results of post hoc analyses of phase 2/3 controlled trials suggest a possible cardioprotective effect with a trend (sometimes significant) toward lower incidence of major cardiovascular events with sitagliptin, vildagliptin, saxagliptin, linagliptin, or alogliptin compared with placebo or other active glucose-lowering agents. However, the definite relationship between DPP-4 inhibition and better cardiovascular outcomes remains to be proven. Major prospective clinical trials involving various DPP-4 inhibitors with predefined cardiovascular outcomes are under way in patients with T2DM and a high-risk cardiovascular profile: the Sitagliptin Cardiovascular Outcome Study (TECOS) on sitagliptin, the Saxagliptin Assessment of Vascular Outcomes Recorded in Patients With Diabetes Mellitus-Thrombolysis in Myocardial Infarction (SAVOR-TIMI) 53 trial on saxagliptin, the Cardiovascular Outcomes Study of Alogliptin in Subjects With Type 2 Diabetes and Acute Coronary Syndrome (EXAMINE) trial on alogliptin, and the Cardiovascular Outcome Study of Linagliptin Versus Glimepiride in Patients With Type 2 Diabetes (CAROLINA) on linagliptin. If these trials confirm that a DPP-4 inhibitor can reduce the cardiovascular burden of T2DM, it would be major progress that would dramatically influence the management of the disease.

Treatment effects on measures of body composition in the TODAY clinical trial

OBJECTIVE

The Treatment Options for type 2 Diabetes in Adolescents and Youth (TODAY) trial showed superiority of metformin plus rosiglitazone (M+R) over metformin alone (M), with metformin plus lifestyle (M+L) intermediate in maintaining glycemic control. We report here treatment effects on measures of body composition and their relationships to demographic and metabolic variables including glycemia.

RESEARCH DESIGN AND METHODS

Measures of adiposity (BMI, waist circumference, abdominal height, percent and absolute fat, and bone mineral content [BMC] and density [BMD]) were analyzed as change from baseline at 6 and 24 months.

RESULTS

Measures of fat accumulation were greatest in subjects treated with M+R and least in M+L. Although fat measures in M+L were less than those of M+R and M at 6 months, differences from M were no longer apparent at 24 months, whereas differences from M+R persisted at 24 months. The only body composition measure differing by race and/or ethnicity was waist circumference, greater in M+R than either M or M+L at both 6 and 24 months in whites. BMD and BMC increased in all groups, but increased less in M+R compared with the other two groups by 24 months. Measures of adiposity (increases in BMI, waist circumference, abdominal height, and fat) were associated with reduced insulin sensitivity and increased hemoglobin A1c (HbA1c), although effects of adiposity on HbA1c were less evident in those treated with M+R.

CONCLUSIONS

Despite differential effects on measures of adiposity (with M+R resulting in the most and M+L in the least fat accumulation), group differences generally were small and unrelated to treatment effects in sustaining glycemic control.

Vildagliptin more effectively achieves a composite endpoint of HbA₁c < 7.0% without hypoglycaemia and weight gain compared with glimepiride after 2 years of treatment

This post hoc analysis reports that overall proportion of patients achieving a composite endpoint of HbA1c<7.0% (<53.0 mmol/mol) without hypoglycaemia and weight gain was higher with vildagliptin than glimepiride after 2 years in type 2 diabetes patients inadequately controlled on metformin monotherapy, regardless of age and duration of diabetes.

Inhibition of the sodium glucose co-transporter-2: its beneficial action and potential combination therapy for type 2 diabetes mellitus

Sodium glucose co-transporter-2 (SGLT2) inhibitors are an emerging class of glucose-lowering drugs in the management of type 2 diabetes mellitus (T2DM). In this context, SGLT2 is a low-affinity, high-capacity transporter that is expressed predominantly in the proximal renal tubules. The rationale for using SGLT2 inhibition as a drug for T2DM is derived from early evidence obtained from individuals with familial renal glycosuria, due to a SGLT2 mutation, which exhibits decreased renal tubular reabsorption of glucose in the absence of hyperglycaemia or any other signs of dysfunction. Thus, reduction of glucose reabsorption by SGLT2 inhibition represents a novel T2DM treatment approach. In light of the emerging role of SGLT2 inhibition in controlling glucose homeostasis, the current review provides a critical appraisal of the rationale, overviews of structural differences between SGLT2 inhibitors and summarizes recent preclinical and clinical studies. The physiological actions of SGLT2 inhibition in relation to insulin sensitivity, islet morphology, inflammation, body weight and blood pressure are reviewed. Finally, the safety and tolerability of SGLT2 inhibitors are also discussed in relation to their potential to provide insulin independence and enhance β-cell function, as well as their potential for synergistic/additive effects if used in combination with other antidiabetic drugs.

Metabolic complications of obesity

Obesity is a risk factor for several metabolic complications, with insulin resistance being the common denominator in these conditions. Impaired blood glucose regulation is one of the most important of these complications, and includes type 2 diabetes mellitus (T2DM), prediabetes, and gestational diabetes. Metabolic syndrome describes a constellation of features including insulin resistance, hypertension, dyslipidemia, and abdominal obesity. Polycystic ovary syndrome is a condition characterized by ovulatory dysfunction and clinical evidence of hyperandrogenism. As many of these complications can go unnoticed for years without overt clinical complications, awareness of both patients and health care professionals is essential such that appropriate screening and diagnostic strategies can be undertaken. Aggressive management strategies of diabetic and prediabetic states are essential for prevention of complications over time. Strategies for identification of vascular risk factors must be implemented such that appropriate risk reduction strategies can be undertaken to minimize the risk of development of cardiovascular complications.

Mechanisms and clinical efficacy of lixisenatide for the management of type 2 diabetes

INTRODUCTION

"Incretin-based" therapies, such as the glucagon-like peptide-1 (GLP-1) receptor agonists, represent a major advance in type 2 diabetes mellitus (T2DM) treatment. GLP-1 receptor agonists differ substantially in their duration of action, frequency of administration and clinical profile.

METHODS

This article reviews the mechanisms of action and clinical evidence for GLP-1 receptor targeting and discusses differences between GLP-1 therapies, focusing particularly on clinical data for the GLP-1 receptor agonist, lixisenatide.

RESULTS

GLP-1 therapies target islet cell "defects" of insufficient insulin and excessive glucagon secretion in T2DM, in a glucose-dependent manner, with minimal risk of hypoglycemia. Different GLP-1 therapies exert differential effects on fasting and postprandial glycemia (both being major determinants of glycemic control). They also slow gastric emptying to different extents, probably accounting for different effects to reduce postprandial glycemia. The GetGoal phase 3 studies in T2DM have confirmed the efficacy of once-daily lixisenatide in reducing plasma glucose and glycated hemoglobin (HbA1c), with a pronounced lowering of postprandial plasma glucose (PPG), as monotherapy and as add-on to oral antidiabetic drugs and to basal insulin. Lixisenatide's ability to diminish PPG is probably partly mediated by its marked ability to delay gastric emptying. Lixisenatide is generally well tolerated, with possibly better gastrointestinal tolerability and lower risk of hypoglycemia than exenatide immediate release. Lixisenatide is associated with a beneficial effect on weight, with either no change or a decrease in body weight when administered as add-on therapy to basal insulin in overweight patients with T2DM.

CONCLUSIONS

Lixisenatide improves glycemic control, by primarily affecting PPG, while preventing weight gain or reducing body weight with a low risk of hypoglycemia in T2DM. Lixisenatide is likely to represent a significant advance in the management of T2DM, perhaps particularly in those patients with relatively faster gastric emptying and lower levels of HbA1c, including those receiving basal insulin.

Cardiovascular effects of gliptins

Dipeptidyl peptidase 4 (DPP-4) inhibitors (commonly referred to as gliptins) are a novel class of oral antihyperglycaemic agents with demonstrated efficacy in the treatment of type 2 diabetes mellitus (T2DM). Preclinical data and mechanistic studies have indicated a possible beneficial action on blood vessels and the heart, via both glucagon-like peptide 1 (GLP-1)-dependent and GLP-1-independent effects. DPP-4 inhibition increases the concentration of many peptides with potential vasoactive and cardioprotective effects. Clinically, DPP-4 inhibitors improve several risk factors in patients with T2DM. They improve blood glucose control (mainly by reducing postprandial glycaemia), are weight neutral (or even induce modest weight loss), lower blood pressure, improve postprandial lipaemia, reduce inflammatory markers, diminish oxidative stress, and improve endothelial function. Some positive effects on the heart have also been described in patients with ischaemic heart disease or congestive heart failure, although their clinical relevance requires further investigation. Post-hoc analyses of phase II-III, controlled trials suggest a possible cardioprotective effect with a trend for a lower incidence of major cardiovascular events with gliptins than with placebo or active agents. However, the actual relationship between DPP-4 inhibition and cardiovascular outcomes remains to be proven. Major prospective clinical trials with predefined cardiovascular outcomes and involving various DPP-4 inhibitors are now underway in patients with T2DM and a high-risk cardiovascular profile.

Weight change with liraglutide and comparator therapies: an analysis of seven phase 3 trials from the liraglutide diabetes development programme

AIM

We investigated the relationship between weight change and related factors in subjects with type 2 diabetes mellitus (T2DM) treated with liraglutide versus comparator diabetes therapies.

METHODS

Twenty-six-week data from seven phase 3, randomized trials in the liraglutide T2DM development programme were analysed by trial and treatment group: liraglutide (1.2 and 1.8 mg), active comparator and placebo. Outcome measures included proportions of subjects in various weight change categories and their percentage weight change from baseline; impact of body mass index (BMI) and gastrointestinal (GI) adverse events (AEs) on weight change and correlation of weight change with change in glycosylated haemoglobin (HbA1c).

RESULTS

A number of subjects experienced >5% weight loss during the trials (24.4% liraglutide 1.8 mg and 17.7% liraglutide 1.2 mg; 17.7% exenatide, 10.0% sitagliptin, 3.6-7.0% sulphonylurea, 2.6% thiazolidinedione and 2.6% glargine; 9.9% placebo). More weight loss was seen with liraglutide 1.2 and 1.8 mg than with active comparators except exenatide. Across trials, higher initial BMI was associated with slightly greater weight loss with liraglutide. Mean weight loss increased slightly the longer GI AEs persisted. Although HbA1c reduction was slightly larger in higher weight loss categories across treatments (including placebo), sample sizes were small and no clear correlation could be determined. Liraglutide-treated subjects experienced additional HbA1c reduction beyond that which appeared weight induced; thus, not all HbA1c-lowering effect appears weight mediated.

CONCLUSIONS

The majority of liraglutide-treated T2DM subjects experienced weight loss in this analysis. Weight loss was greater and occurred more in glucagon-like peptide-1 receptor agonist-treated subjects than in active comparator-treated subjects.

Rosiglitazone decreases fasting plasma peptide YY3-36 in type 2 diabetic women: a possible role in weight gain?

Rosiglitazone often results in weight gain. We hypothesized that rosiglitazone may modulate circulating levels of ghrelin and peptide YY(3-36) and this modulation may be related to weight-gaining effect of this agent. This study was designed as an open-label, randomized, controlled trial of 3-month duration. Women with newly diagnosed type 2 diabetes were studied. Twenty-eight of the 55 eligible participants were randomly assigned to receive rosiglitazone (4 mg/d). Twenty-seven patients with diabetes matched for age and body mass index served as controls on diet alone. We evaluated the effects of 3 months of rosiglitazone treatment on fasting peptide YY(3-36) and ghrelin levels, and anthropometric measurements. The 3-month administration of rosiglitazone reduced fasting plasma peptide YY(3-36) levels by 25%, the between-group difference was statistically significant. No effect of this thiazolidinedione compound on fasting ghrelin concentrations was observed at the end of study. The ghrelin/body mass index ratio also did not change significantly after treatment. Seventy-five percent of the women with diabetes complained of increased hunger at the end of study. Nevertheless, all subjects exhibited a decrease in fasting PYY levels after 3 months of rosiglitazone therapy, irrespective of the levels of hunger. There was no significant correlation between changes in peptide YY(3-36) and those in anthropometric parameters and insulin sensitivity at the end of the study. Rosiglitazone-induced decrease in fasting peptide YY(3-36) levels may in part contribute to orexigenic and weight-gaining effect of this thiazolidinedione derivative.

Addition of exenatide twice daily to basal insulin for the treatment of type 2 diabetes: clinical studies and practical approaches to therapy

BACKGROUND

Type 2 diabetes is a progressive disease that requires stepwise additions of non-insulin and insulin therapies to meet recommended glycaemic goals. The final stage of intensification may require prandial insulin, adding complexity and increased risks of hypoglycaemia and weight gain.

AIMS

This review assesses the benefits and risks of adding exenatide twice daily, a glucagon-like peptide 1 receptor agonist, in patients with type 2 diabetes who are currently treated with basal insulin, but have failed to reach their glycaemic goals.

METHODS AND RESULTS

Based on data from published studies, exenatide has a number of actions that complement basal insulin therapy. Exenatide has been shown to increase glucose-dependent insulin production, suppress abnormal plasma glucagon production, slow gastric emptying, enhance liver uptake of glucose and promote satiety. A recently published randomised clinical trial reported that the addition of exenatide twice daily to titrated basal insulin provided greater glycaemic control than titrated basal insulin alone, and did so without an increase in hypoglycaemic events and with modest weight loss. Exenatide use was associated with gastrointestinal side effects. The recent randomised trial confirmed and extended data from a number of prior observational studies that demonstrated the efficacy and safety of insulin/exenatide combination therapy. Practical considerations for adding exenatide twice daily to ongoing basal insulin are discussed.

Second line therapy: type 2 diabetic subjects failing on metformin GLP-1/DPP-IV inhibitors versus sulphonylurea/insulin: for GLP-1/DPP-IV inhibitors

Following diagnosis, type 2 diabetic subjects are invariably treated with life style modifications and metformin. However, majority of these subjects require addition of another therapeutic agent singly or in combination; with or without insulin within few months to few years. For several decades, sulphonylureas and insulin have been the second line agent of choice. Clinical practice guidelines also suggest a similar approach. Subsequently thiazolidinediones, alpha glucose inhibitors and other agents were added to therapeutic armamentarium. Unfortunately, none of these treatment options could address the issue of progressive decline in beta cell function. Furthermore, they are responsible for unacceptable incidence of hypoglycaemia, weight gain and other side effects related to individual agents. Type 2 diabetic subjects have great propensity to develop cardiovascular complications. Sulphonylureas, insulin and thiazolidinediones have all been associated with adverse cardiovascular outcomes in differing magnitude. It has been made mandatory by regulatory agencies to ensure cardiovascular safety of any new anti-diabetic agent. Glucagon Like Peptide-1(GLP-1)-based therapies have been able to address several of these issues. Incretin mimetics and Di Peptidyl Dipeptidase IV (DPP-IV) inhibitors cause glucose-dependent insulin secretion and glucagon suppression from beta and alpha cells of the pancreas respectively. They owe this property to their binding with G-Protein-coupled receptors leading to an increased amount of c-AMP. They do not cause beta cell exhaustion. On the contrary such agents prevent beta cell apoptosis. Clinical trials have established the superiority of incretin mimetics particularly liraglutide against comparators including glimepiride, rosiglitazone and insulin Glargine in terms of efficacy. Furthermore, they have shown evidence towards beta cell protection, significant weight loss, minimal hypoglycaemia and favourable impact on surrogate markers of cardiovascular outcomes. DPP-IV inhibitors have limited ability to achieve glycaemic targets. However, they are weight neutral, cause minimal hypoglycaemia and have some beneficial effect on beta cell function. Finally, they are very well tolerated.

Novel therapeutics and targets for the treatment of diabetes

The microvascular complications of insufficiently controlled diabetes (neuropathy, retinopathy and nephropathy) and the marked increased risk of macrovascular events (e.g., stroke and myocardial infarction) have a dire impact on society in both human and economic terms. In Type 1 diabetes total β-cell loss occurs. In Type 2 diabetes, partial β-cell loss occurs before diagnosis, and the progressive β-cell loss during the life of the patient increases the severity of the disease. In patients with diabetes, increased insulin resistance in the muscle and liver are key pathophysiologic defects. In addition, defects in metabolic processes in the fat, GI tract, brain, pancreatic α-cells and kidney are detrimental to the overall health of the patient. This review addresses novel therapies for these deficiencies in clinical and preclinical evaluation, emphasizing their potential to address glucose homeostasis, β-cell mass and function, and the comorbidities of cardiovascular disease and obesity.

Incretin-based therapy in combination with basal insulin: a promising tactic for the treatment of type 2 diabetes

Incretin therapies such as dipeptidyl peptidase-4 inhibitors (DPP-4Is) and GLP-1 receptor agonists (GLP-1RAs) have become well-established treatments for type 2 diabetes. Both drug classes reduce blood glucose through physiological pathways mediated by the GLP-1 receptor, resulting in glucose-dependent enhancement of residual insulin secretion and inhibition of glucagon secretion. In addition, the GLP-1RAs reduce gastrointestinal motility and appear to have appetite-suppressing actions and, so, are often able to produce clinically useful weight loss. The glucose-dependency of their glucagon-inhibiting and insulin-enhancing effects, together with their weight-sparing properties, make the incretin therapies a logical proposition for use in combination with exogenous basal insulin therapy. This combination offers the prospect of an additive or synergistic glucose-lowering effect without a greatly elevated risk of hypoglycaemia compared with insulin monotherapy, and any insulin-associated weight gain might also be mitigated. Furthermore, the incretin therapies can be combined with metformin, which is usually continued when basal insulin is introduced in type 2 diabetes. Although the combination of incretin and insulin therapy is currently not addressed in internationally recognized treatment guidelines, several clinical studies have assessed its use. The data, summarized in this review, are encouraging and show that glycaemic control is improved and weight gain is limited or reversed (especially with the combined use of GLP-1RAs and basal insulin), and that the use of an incretin therapy can also greatly reduce insulin dose requirements. The addition of basal insulin to established incretin therapy is straightforward, but insulin dose adjustment (though not discontinuation) is usually necessary if the sequence is reversed.

A retrospective database study of insulin initiation in patients with Type 2 diabetes in UK primary care

AIMS

This study characterized UK primary care patients with Type 2 diabetes who initiated insulin treatment, and described the initial insulin regimens used, overall metabolic changes and health-care resource usage.

METHODS

A retrospective cohort study was performed using quality-checked patient data from The Health Improvement Network database. Eligible patients who initiated insulin for the first time between 2004 and 2006 were grouped into four cohorts according to the type of insulin regimen initiated. Data on patient characteristics, metabolic and clinical outcomes and health-care resource use were collected at baseline and during 6 months of follow-up.

RESULTS

In total, 4045 eligible adults [2269 male, 1776 female; mean age 62.6 ± 13.3 years; mean baseline HbA(1c) 82 ± 22 mmol/mol (9.6% ± 2.0%)] initiated insulin. Approximately half (52.4%) initiated insulin as basal insulin only, 41.6% as premixed only, 4.0% as basal-bolus and 2.1% as prandial insulin only. Among patients with ≥ 180 days follow-up (n=3815), the initial insulin regimen was not changed during follow-up in 75.1% of patients, while 13.7% discontinued, 7.0% switched and 4.7% intensified insulin therapy. The mean change in HbA(1c) was -14 mmol/mol (-1.3%, n=2881), with 17.3% of patients achieving an HbA(1c) of <53 mmol/mol (7%, n=3024). The mean weight change was +0.9 kg (n=2345).

CONCLUSIONS

Basal and premixed insulin were the most common types of insulin initiated and in most patients no changes were made to the initial regimen over 6 months. However, few patients achieved glycemic control targets.

Glycaemia and correlates of patient-reported outcomes in ACCORD trial participants

AIMS

Post-hoc evaluation of relationships between first-year change in glycaemic control (HbA(1c) ) and change in patient-reported outcomes among ACCORD health-related quality of life (HRQoL) substudy participants.

METHODS

Data from 2053 glycaemia-trial subjects were analysed. We assessed physical and mental health status (36-Item Short Form Health Survey, Version-2), symptom count and severity (Diabetes Symptoms Distress Checklist) and treatment satisfaction (Diabetes Treatment Satisfaction Questionnaire). Linear mixed models were used to test relationships between 1-year changes in HbA(1c) and patient reported outcomes sequentially adjusting for correlates (baseline characteristics, baseline patient reported outcomes, treatment assignment, frequency of clinical contact and post-randomization weight change plus new complications).

RESULTS

Poorer baseline control of HbA(1c) and cardiovascular disease risk factors predicted greater one-year improvements in treatment satisfaction. Similarly, poorer baseline patient reported outcome scores all individually predicted greater 1-year improvement in that same outcome. Accounting for baseline and post-randomization characteristics and treatment arm, 1-year change in HbA(1c) was unrelated to changes in overall physical or mental health; however, every one percentage-point (10.9 mmol/mol) reduction in HbA(1c) was associated with lower symptom count (β = 0.599; P = 0.012), lower symptom distress (β = 0.051; P = 0.001), and higher treatment satisfaction (β = -2.514; P < 0.001).

CONCLUSIONS

Independent of all relevant covariates, better glycaemic control over 1 year was associated with reduced patient-reported diabetes symptoms and symptom distress, and increased treatment satisfaction, but not overall physical and mental health. Further investigation is required to understand the specific psychosocial mechanisms that affect how patients value health and treatments.

Comparison of 2 intensification regimens with rapid-acting insulin aspart in type 2 diabetes mellitus inadequately controlled by once-daily insulin detemir and oral antidiabetes drugs: the step-wise randomized study

OBJECTIVE

To compare the efficacy and safety of 2 intensification strategies for stepwise addition of prandial insulin aspart in patients with type 2 diabetes mellitus treated with insulin detemir.

METHODS

This randomized, controlled, parallel-group, open-label, 48-week trial compared the stepwise addition of insulin aspart to either the largest meal (titration based on premeal glucose values [SimpleSTEP]) or to the meal with the largest prandial glucose increment (titration based on postmeal glucose values [ExtraSTEP]) in patients with type 2 diabetes inadequately controlled on basal insulin and oral antidiabetes drugs. After 12 weeks of basal insulin detemir dosage optimization, participants with a hemoglobin A1c level of 7% or greater entered three 12-week treatment periods with stepwise addition of a first insulin aspart bolus, then a second, and then a third, if hemoglobin A1c remained at 7% or greater after 12 and 24 weeks of treatment, respectively. Endpoints included hemoglobin A1c (primary endpoint), fasting plasma glucose, self-measured plasma glucose, adverse events, and hypoglycemia.

RESULTS

Two hundred ninety-six patients were randomly assigned to treatment with insulin aspart in the SimpleSTEP (n = 150) and ExtraSTEP (n = 146) groups. Hemoglobin A1c decreased by approximately 1.2% in both groups, to 7.5 ± 1.1% (Simple-STEP) and 7.7 ± 1.2% (ExtraSTEP) at end of trial (estimated treatment difference, SimpleSTEP - ExtraSTEP: -0.06% [95% confidence interval, -0.29 to 0.17]). Self-measured plasma glucose levels decreased with both regimens. At trial end, approximately 75% of patients in each group were using 3 prandial injections. The frequency of adverse events and hypoglycemia was low and similar between groups.

CONCLUSION

The SimpleSTEP and ExtraSTEP strategies for stepwise addition of insulin aspart to 1 or more meals were equally effective at intensifying therapy in patients with type 2 diabetes not achieving glycemic control on basal insulin and oral antidiabetic drugs.

Observational 6-Month Open-Label Study of Japanese Type 2 Diabetes Patients Switching from NPH Insulin to Insulin Detemir in Basal—Bolus Regimen: 23rd Article of the Japan Diabetes Clinical Data Management Study Group (JDDM23)

OBJECTIVE: Glycaemic control is critical to prevent diabetic complications and mortality. This 6-month, open-label, observational study assessed the efficacy and safety of switching Japanese patients with type 2 diabetes from neutral protamine Hagedorn (NPH) insulin to insulin detemir. METHODS: Patients with type 2 diabetes ( n = 126) receiving basal—bolus insulin therapy with NPH insulin plus rapid-acting insulin analogues were recruited. NPH insulin was replaced with insulin detemir for 6 months. Glycosylated haemoglobin (HbA1c), fasting plasma glucose (FPG), daily glucose levels and hypoglycaemia were monitored. Nocturnal quality of life was assessed by insulin therapy related quality of life at night questionnaire. RESULTS: HbA1c, FPG and body weight were all significantly reduced after treatment with insulin detemir for 6 months, without increasing severe hypoglycaemia. Insulin dose increased significantly over the same time. There were significant improvements in overall nocturnal quality of life, as well as well-being. CONCLUSIONS: Treatment with insulin detemir for 6 months resulted in substantial benefits, including reduced HbA1c, FPG and body weight, and improvements in nocturnal quality of life, without increasing hypoglycaemia.

Effects of dapagliflozin on body weight, total fat mass, and regional adipose tissue distribution in patients with type 2 diabetes mellitus with inadequate glycemic control on metformin

CONTEXT

Dapagliflozin, a selective sodium-glucose cotransporter 2 (SGLT2) inhibitor, reduces hyperglycemia in patients with type 2 diabetes mellitus (T2DM) by increasing urinary glucose excretion, and weight loss is a consistent associated finding.

OBJECTIVES

Our objectives were to confirm weight loss with dapagliflozin and establish through body composition measurements whether weight loss is accounted for by changes in fat or fluid components.

DESIGN AND SETTING

This was a 24-wk, international, multicenter, randomized, parallel-group, double-blind, placebo-controlled study with ongoing 78-wk site- and patient-blinded extension period at 40 sites in five countries.

PATIENTS

Included were 182 patients with T2DM (mean values: women 63.3 and men 58.6 yr of age; hemoglobin A1c 7.17%, body mass index 31.9 kg/m2, and body weight 91.5 kg) inadequately controlled on metformin.

INTERVENTION

Dapagliflozin 10 mg/d or placebo was added to open-label metformin for 24 wk.

MAIN OUTCOME MEASURES

Primary endpoint was total body weight (TBW) change from baseline at wk 24. Key secondary endpoints were waist circumference and dual-energy x-ray absorptiometry total-body fat mass (FM) changes from baseline at wk 24, and patient proportion achieving body weight reduction of at least 5% at wk 24. In a subset of patients, magnetic resonance assessment of visceral adipose tissue (VAT) and sc adipose tissue (SAT) volume and hepatic lipid content were also evaluated.

RESULTS

At wk 24, placebo-corrected changes with dapagliflozin were as follows: TBW, -2.08 kg [95% confidence interval (CI)=-2.84 to -1.31; P<0.0001]; waist circumference, -1.52 cm (95% CI=-2.74 to -0.31; P=0.0143); FM, -1.48 kg (95% CI=-2.22 to -0.74; P=0.0001); proportion of patients achieving weight reduction of at least 5%, +26.2% (95% CI=15.5 to 36.7; P<0.0001); VAT, -258.4 cm3 (95% CI=-448.1 to -68.6; nominal P=0.0084); SAT, -184.9 cm3 (95% CI=-359.7 to -10.1; nominal P=0.0385). In the dapagliflozin vs. placebo groups, respectively, serious adverse events were reported in 6.6 vs. 1.1%; events suggestive of vulvovaginitis, balanitis, and related genital infection in 3.3 vs. 0%; and lower urinary tract infections in 6.6 vs. 2.2%.

CONCLUSIONS

Dapagliflozin reduces TBW, predominantly by reducing FM, VAT and SAT in T2DM inadequately controlled with metformin.

The central insulin system and energy balance

Insulin acts throughout the body to reduce circulating energy and to increase energy storage. Within the brain, insulin produces a net catabolic effect by reducing food intake and increasing energy expenditure; this is evidenced by the hypophagia and increased brown adipose tissue sympathetic nerve activity induced by central insulin infusion. Reducing the activity of the brain insulin system via administration of insulin antibodies, receptor antisense treatment, or receptor knockdown results in hyperphagia and increased adiposity. However, despite decades of research into the role of central insulin in food intake, many questions remain to be answered, including the underlying mechanism of action.

Incretin therapy--present and future

Although newer treatments for type 2 diabetes (T2D) patients have produced continual improvements in outcome, a large and growing population with prediabetes remains under-treated. In the last few years, incretin-based therapies have become an important treatment option for patients with T2D. There are two classes of incretin agents: the dipeptidyl peptidase-4 (DPP-4) inhibitors and the glucagon like peptide 1 (GLP-1) receptor agonists. The ultimate goal of agents within both of these classes is to increase GLP-1 signaling, which results in augmented glucose-induced insulin secretion, inhibition of glucagon secretion, and decreased appetite. This should result in improved regulation of glucose homeostasis. GLP-1 receptor agonists enable patients to achieve significant weight loss. In contrast, DPP-4 inhibitors result in a less dramatic increase in GLP-1 levels; therefore, they are weight neutral. Incretin therapies are currently recommended for use early in the treatment algorithm for T2D patients whose disease is not manageable by diet and exercise alone, but the potential for these agents may be farther reaching. Current studies are evaluating the potential benefits of combining incretin therapies with basal insulin to provide continuous glucose control before and after meals. In addition, these agents may be promising for patients with prediabetes since they effectively reduce glycosylated hemoglobin levels and fasting plasma glucose levels, enable weight control, and have the potential to preserve β-cell function. Clearly, all of these properties are desirable for patients with prediabetes.

The evaluation and management of childhood type 2 diabetes mellitus

Diabetes in children is increasing in prevalence with obesity-associated insulin resistance being a major contributing factor. This report contains a comprehensive review of treatment paradigms regarding the management of diabetes in children. The information provided was collected from an extensive literature review on type 2 diabetes, and children and/or adolescents with diabetes and/or obesity treatment. There is a wide array of contributing factors to the development of diabetes and consequences that indicate the need to tailor treatment plans with reducing obesity as a primary outcome. Lipocentric treatment paradigms offer opportunity to reduce the impact of obesity.

Development and potential role of type-2 sodium-glucose transporter inhibitors for management of type 2 diabetes

There is a recognized need for new treatment options for type 2 diabetes mellitus (T2DM). Recovery of glucose from the glomerular filtrate represents an important mechanism in maintaining glucose homeostasis and represents a novel target for the management of T2DM. Recovery of glucose from the glomerular filtrate is executed principally by the type 2 sodium-glucose cotransporter (SGLT2). Inhibition of SGLT2 promotes glucose excretion and normalizes glycemia in animal models. First reports of specifically designed SGLT2 inhibitors began to appear in the second half of the 1990s. Several candidate SGLT2 inhibitors are currently under development, with four in the later stages of clinical testing. The safety profile of SGLT2 inhibitors is expected to be good, as their target is a highly specific membrane transporter expressed almost exclusively within the renal tubules. One safety concern is that of glycosuria, which could predispose patients to increased urinary tract infections. So far the reported safety profile of SGLT2 inhibitors in clinical studies appears to confirm that the class is well tolerated. Where SGLT2 inhibitors will fit in the current cascade of treatments for T2DM has yet to be established. The expected favorable safety profile and insulin-independent mechanism of action appear to support their use in combination with other antidiabetic drugs. Promotion of glucose excretion introduces the opportunity to clear calories (80-90 g [300-400 calories] of glucose per day) in patients that are generally overweight, and is expected to work synergistically with weight reduction programs. Experience will most likely lead to better understanding of which patients are likely to respond best to SGLT2 inhibitors, and under what circumstances.

Emerging role of insulin with incretin therapies for management of type 2 diabetes

Type 2 diabetes mellitus (T2DM) is a progressive disease warranting intensification of treatment, as beta-cell function declines over time. Current treatment algorithms recommend metformin as the first-line agent, while advocating the addition of either basal-bolus or premixed insulin as the final level of intervention. Incretin therapy, including incretin mimetics or enhancers, are the latest group of drugs available for treatment of T2DM. These agents act through the incretin axis, are currently recommended as add-on agents either as second-or third-line treatment, without concurrent use of insulin. Given the novel role of incretin therapy in terms of reducing postprandial hyperglycemia, and favorable effects on weight with reduced incidence of hypoglycemia, we explore alternative options for incretin therapy in T2DM management. Furthermore, as some evidence alludes to incretins potentially increasing betacell mass and altering disease progression, we propose introducing these agents earlier in the treatment algorithm. In addition, we suggest the concurrent use of incretins with insulin, given the favorable effects especially in relation to weight gain.

Advances in the treatment of type 2 diabetes mellitus

There is a rising worldwide prevalence of diabetes, especially type 2 diabetes mellitus (T2DM), which is one of the most challenging health problems in the 21st century. The associated complications of diabetes, such as cardiovascular disease, peripheral vascular disease, stroke, diabetic neuropathy, amputations, renal failure, and blindness result in increasing disability, reduced life expectancy, and enormous health costs. T2DM is a polygenic disease characterized by multiple defects in insulin action in tissues and defects in pancreatic insulin secretion, which eventually leads to loss of pancreatic insulin-secreting cells. The treatment goals for T2DM patients are effective control of blood glucose, blood pressure, and lipids (if elevated) and, ultimately, to avert the serious complications associated with sustained tissue exposure to excessively high glucose concentrations. Prevention and control of diabetes with diet, weight control, and physical activity has been difficult. Treatment of T2DM has centered on increasing insulin levels, either by direct insulin administration or oral agents that promote insulin secretion, improving sensitivity to insulin in tissues, or reducing the rate of carbohydrate absorption from the gastrointestinal tract. This review presents comprehensive and up-to-date information on the mechanism(s) of action, efficacy, pharmacokinetics, pleiotropic effects, drug interactions, and adverse effects of the newer antidiabetic drugs, including (1) peroxisome proliferator-activated-receptor-γ agonists (thiazolidinediones, pioglitazone, and rosiglitazone); (2) the incretin, glucagon-like peptide-) receptor agonists (incretin-mimetics, exenatide. and liraglutide), (3) inhibitors of dipeptidyl-peptidase-4 (incretin enhancers, sitagliptin, and vildagliptin), (4) short-acting, nonsulfonylurea secretagogue, meglitinides (repaglinide and nateglinide), (5) amylin anlog-pramlintide, (6) α-glucosidase inhibitors (miglitol and voglibose), and (7) colesevelam (a bile acid sequestrant). In addition, information is presented on drug candidates in clinical trials, experimental compounds, and some plants used in the traditional treatment of diabetes based on experimental evidence. In the opinion of this reviewer, therapy based on orally active incretins and incretin mimetics with long duration of action that will be efficacious, preserve the β-cell number/function, and block the progression of diabetes will be highly desirable. However, major changes in lifestyle factors such as diet and, especially, exercise will also be needed if the growing burden of diabetes is to be contained.

Use of metformin in the treatment of polycystic ovary syndrome

Metformin is quite an old drug, but it is optimal for the control of glycemia in Type 2 diabetes. It was reported, 15 years ago, that insulin resistance was abnormally high in most polycystic ovary syndrome (PCOS) patients. Starting from that moment, increasing numbers of studies were performed to demonstrate the efficacy of metformin in controlling and/or modulating several aspects of PCOS, which is the most common cause of menstrual irregularity, inesthetisms and infertility. Metformin induces higher glucose uptake, thus inducing a lower synthesis/secretion of insulin. Such an effect permits the possible restoration of the normal biological functions that are severely affected by the compensatory hyperinsulinemia reactive to the increased peripheral insulin resistance. These are the basis of the many positive effects of this drug, such as the restoration of menstrual cyclicity, ovulatory cycles and fertility, because abnormal insulin levels affect the hypothalamus-pituitary-ovarian function, as well as the use of glucose in peripheral tissues. Metformin improves the impairments typically observed in hyperinsulinemic PCOS patients, reducing the possible evolution towards metabolic syndrome and Type 2 diabetes; and when pregnancy occurs, it consistently reduces the risk of gestational diabetes, eclampsia and hypertension. PCOS seems to be the perfect physiopathological condition that might have higher benefits from metformin administration, obviously after Type 2 diabetes. This review focuses on the many aspects of PCOS and on the possible issues of this disease for which metformin might be a putative optimal treatment.

Safety and efficacy of saxagliptin added to thiazolidinedione over 76 weeks in patients with type 2 diabetes mellitus

To assess the long-term efficacy and safety of saxagliptin in patients with type 2 diabetes mellitus inadequately controlled with thiazolidinedione monotherapy, 565 patients were randomised to saxagliptin (2.5 mg or 5 mg) or placebo added to thiazolidinedione over 76 weeks (24-week short-term + 52-week long-term extension period) in this phase 3, double-blind, placebo-controlled trial; 360 patients completed the study. At 76 weeks, adjusted mean changes from baseline HbA(1C) (repeated measures model; 95% CI) for saxagliptin 2.5 mg, 5 mg, and placebo were -0.59% (-0.75, -0.43), -1.09% (-1.26, -0.93), and -0.20% (-0.39, -0.01), respectively (post hoc and nominal p=0.0019 and p<0.0001 for saxagliptin 2.5 mg and 5 mg vs. placebo, respectively). Adverse event frequency was similar between groups. Confirmed hypoglycaemic events were 1.0% and 0% vs. 0.5% for saxagliptin 2.5 mg and 5 mg vs. placebo, respectively. Results should be interpreted with caution given the proportion of patients who discontinued or required glycaemic rescue therapy during the 76-week course of study. Saxagliptin added to thiazolidinedione provided sustained incremental efficacy vs. placebo with little hypoglycaemia for up to 76 weeks and was generally well tolerated.

The safety of thiazolidinediones

INTRODUCTION

The prevalence of type 2 diabetes mellitus (T2DM) has reached epidemic proportions. Many new therapies have emerged, including thiazolidinediones (TZDs), selective agonists of PPAR-γ, now used as both primary and add-on therapies. Given that T2DM is a lifetime disease, there is a need for assurance that new drugs are both safe and effective. Recent concern about the cardiovascular safety of one of the new drugs, rosiglitazone, is the stimulus for this review.

AREAS COVERED

The safety of pioglitazone and rosiglitazone under the headings of liver safety, cardiovascular safety, fluid retention, weight gain and bone fractures is reviewed based on a PubMed search of the years 1997 through June 2010. This review also describes the magnitude of the risks of the TZDs and provides a recommendation on the use of TZDs.

EXPERT OPINION

Liver safety is no longer an issue with the TZDs. There are no significant differences between rosiglitazone and pioglitazone in fluid retention, weight gain and bone fractures. However, pioglitazone tends to be cardioprotective while rosiglitazone is cardiotoxic. There is no current justification for prescribing rosiglitazone.

Weight change with long-term duloxetine use in chronic painful conditions: an analysis of 16 clinical studies

AIMS

Report weight change baseline up to 12-15 months in duloxetine-treated patients during clinical trials of chronic painful conditions of diabetic peripheral neuropathic pain (DPNP), fibromyalgia, chronic low back pain (CLBP) and chronic knee pain as a result of osteoarthritis.

METHODS

Weight change data from 16 duloxetine studies in chronic painful conditions were pooled by pain condition and duration, creating 10 datasets. Datasets included placebo-controlled, open-label and routine-care-controlled designs. Assessments included mean weight change from baseline, baseline body mass index category, potentially clinically significant (PCS) weight change and weight-related treatment-emergent adverse events.

RESULTS

Total number of patients was 5111 with mean baseline weight ranging from 70 to 97 kg. All duloxetine groups had significant mean weight loss compared with placebo at acute phase completion (p ≤ 0.001). In studies > 3 months, patients from fibromyalgia and CLBP studies had overall mean weight increase (up to 1.1 kg), whereas patients in DPNP studies had overall mean weight loss (-0.33 to -1.7 kg) at end-point. Overall, the percentage of patients with PCS weight gain was 0.4-16% and PCS weight loss was 2.5-9.9%.

DISCUSSION

Weight change data in clinical trials of patients with fibromyalgia or CLBP treated with duloxetine for up to 15 months were consistent with data reported in 10 clinical trials of patients with major depressive disorder (MDD) using duloxetine up to 52 weeks. Patients with DPNP had weight loss at end-point.

CONCLUSION

Mean weight changes and percentages of patients with PCS weight loss and weight gain observed in DPNP, fibromyalgia and CLBP with long-term duloxetine treatment were consistent with those reported previously for MDD studies.

Safety and efficacy of linagliptin as add-on therapy to metformin in patients with type 2 diabetes: a randomized, double-blind, placebo-controlled study

AIM

To evaluate the efficacy and safety of the potent and selective dipeptidyl peptidase-4 (DPP-4) inhibitor linagliptin administered as add-on therapy to metformin in patients with type 2 diabetes with inadequate glycaemic control.

METHODS

This 24-week, randomized, placebo-controlled, double-blind, parallel-group study was carried out in 82 centres in 10 countries. Patients with HbA1c levels of 7.0-10.0% on metformin and a maximum of one additional antidiabetes medication, which was discontinued at screening, continued on metformin ≥1500 mg/day for 6 weeks, including a placebo run-in period of 2 weeks, before being randomized to linagliptin 5 mg once daily (n = 524) or placebo (n = 177) add-on. The primary outcome was the change from baseline in HbA1c after 24 weeks of treatment, evaluated with an analysis of covariance (ANCOVA).

RESULTS

Mean baseline HbA1c and fasting plasma glucose (FPG) were 8.1% and 9.4 mmol/l, respectively. Linagliptin showed significant reductions vs. placebo in adjusted mean changes from baseline of HbA1c (-0.49 vs. 0.15%), FPG (-0.59 vs. 0.58 mmol/l) and 2hPPG (-2.7 vs. 1.0 mmol/l); all p < 0.0001. Hypoglycaemia was rare, occurring in three patients (0.6%) treated with linagliptin and five patients (2.8%) in the placebo group. Body weight did not change significantly from baseline in both groups (-0.5 kg placebo, -0.4 kg linagliptin).

CONCLUSIONS

The addition of linagliptin 5 mg once daily in patients with type 2 diabetes inadequately controlled on metformin resulted in a significant and clinically meaningful improvement in glycaemic control without weight gain or increased risk of hypoglycaemia.

The novel sodium glucose transporter 2 inhibitor dapagliflozin sustains pancreatic function and preserves islet morphology in obese, diabetic rats

AIMS

To investigate whether glucose lowering with the selective sodium glucose transporter 2 (SGLT2) inhibitor dapagliflozin would prevent or reduce the decline of pancreatic function and disruption of normal islet morphology.

METHODS

Female Zucker diabetic fatty (ZDF) rats, 7-8 weeks old, were placed on high-fat diet. Dapagliflozin (1 mg/kg/day, p.o.) was administered for ∼33 days either from initiation of high-fat diet or when rats were moderately hyperglycaemic. Insulin sensitivity and pancreatic function were evaluated using a hyperglycaemic clamp in anaesthetized animals (n = 5-6); β-cell function was quantified using the disposition index (DI) to account for insulin resistance compensation. Pancreata from a matched subgroup (n = 7-8) were fixed and β-cell mass and islet morphology investigated using immunohistochemical methods.

RESULTS

Dapagliflozin, administered from initiation of high-fat feeding, reduced the development of hyperglycaemia; after 24 days, blood glucose was 8.6 ± 0.5 vs. 13.3 ± 1.3 mmol/l (p < 0.005 vs. vehicle) and glycated haemoglobin 3.6 ± 0.1 vs. 4.8 ± 0.26% (p < 0.003 vs. vehicle). Dapagliflozin improved insulin sensitivity index: 0.08 ± 0.01 vs. 0.02 ± 0.01 in obese controls (p < 0.03). DI was improved to the level of lean control rats (dapagliflozin 0.29 ± 0.04; obese control 0.15 ± 0.01; lean 0.28 ± 0.01). In dapagliflozin-treated rats, β-cell mass was less variable and significant improvement in islet morphology was observed compared to vehicle-treated rats, although there was no change in mean β-cell mass with dapagliflozin. Results were similar when dapagliflozin treatment was initiated when animals were already moderately hyperglycaemic.

CONCLUSION

Sustained glucose lowering with dapagliflozin in this model of type 2 diabetes prevented the continued decline in functional adaptation of pancreatic β-cells.

Saxagliptin and metformin XR combination therapy provides glycemic control over 24 hours in patients with T2DM inadequately controlled with metformin

OBJECTIVE

To assess 24-hour glycemic control with saxagliptin compared with placebo as add-on treatment to metformin in patients with type 2 diabetes mellitus (T2DM) and inadequate glycemic control.

RESEARCH DESIGN AND METHODS

This was a 4-week, multicenter, randomized, double-blind, placebo-controlled Phase IIIb trial comparing the antihyperglycemic activity of saxagliptin 5 mg once daily in combination with a stable dose of metformin extended release (XR) vs. placebo in combination with metformin XR in patients with T2DM inadequately controlled (screening glycated hemoglobin [HbA(1c)] 7-10%) with stable doses of metformin immediate release or metformin XR ≥ 1500 mg/day. Ninety-three adult patients were randomized and received treatment. The primary outcome measure was change from baseline to week 4 in 24-hour mean weighted glucose (MWG).

RESULTS

The reduction from baseline in 24-hour MWG was significantly greater for saxagliptin 5 mg + metformin XR (-13.8 mg/dL; -0.77 mmol/L) compared with placebo + metformin XR (3.0 mg/dL; 0.17 mmol/L) (p = 0.0001). At week 4, the mean decrease in plasma glucose was sustained through a 24-hour period in saxagliptin-treated patients. Treatment with saxagliptin 5 mg + metformin XR resulted in significant mean reductions from baseline in 4-hour mean weighted postprandial glucose (PPG), 2-hour PPG, 3-day average mean daily glucose, and fasting plasma glucose levels compared with placebo + metformin XR (p ≤ 0.001). The proportion of adverse events (AEs) was similar in the two treatment groups, with no reported hypoglycemic AEs in saxagliptin-treated patients. The 4-week evaluation period may have been insufficient to evaluate longer term effects on hyperglycemia or to identify additional AEs.

CONCLUSIONS

In patients with T2DM treated with metformin XR, saxagliptin 5 mg orally administered once daily in the evening for 4 weeks effectively lowered plasma glucose concentrations through the 24-hour dosing interval and was well tolerated.

The future use of liraglutide: implications of the LEAD-2 study for treatment guidelines in type 2 diabetes

The effective identification and management of type 2 diabetes (T2D) in primary care is a healthcare priority. New antidiabetic agents, including glucagon-like peptide (GLP)-1 receptor agonists, may help overcome drawbacks with current treatments. These new agents have been reviewed in the updated National Institute for Health and Clinical Excellence (NICE) guidelines for the treatment of T2D. Liraglutide, a GLP-1 receptor agonist, was licensed for use in patients with T2D after the development of the NICE guidelines. Data from Phase III trials evaluating liraglutide are presented here in the context of the role of GLP-1 receptor agonists in NICE guidelines.

The adjunctive use of metformin to treat or prevent atypical antipsychotic-induced weight gain: a review

Patients with schizophrenia have a greater incidence of being overweight or obese compared with the general population. Such individuals are often treated with second-generation (atypical) antipsychotics (SGAs), which are associated with weight gain, dyslipidemia, and other metabolic derangements. As a result, frequent monitoring of weight and other metabolic parameters is recommended. In addition, several pharmacologic strategies to help prevent or reduce SGA-induced weight gain have been proposed. Despite this, clinicians often struggle to manage obesity and metabolic issues in such patients. Metformin has attracted attention as a potential treatment option because it is thought to result in weight reduction and improved glycemic control in obese patients with and without type 2 diabetes mellitus. This article focuses on relevant pharmacologic aspects of metformin and reviews currently available evidence on the use of metformin as an augmentation agent for the treatment or prevention of SGA-induced weight gain.

Glycaemic goals in patients with type 2 diabetes: current status, challenges and recent advances

Recommendations for the management of type 2 diabetes include rigorous control of blood glucose levels and other risk factors, such as hypertension and dyslipidaemia. In clinical practice, many patients do not reach goals for glycaemic control. Causes of failure to control blood glucose include progression of underlying pancreatic beta-cell dysfunction, incomplete adherence to treatment (often because of adverse effects of weight gain and hypoglycaemia) and reluctance of clinicians to intensify therapy. There is increasing focus on strategies that offer potential to improve glycaemic control. Structured patient education has been shown to improve glycaemic control and other cardiovascular risk factors in people with type 2 diabetes. Payment of general practitioners by results has been shown to improve glycaemic control. New classes of glucose-lowering agents have expanded the treatment options available to clinicians and patients and include the dipeptidyl peptidase 4 (DPP-4) inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists. These new classes of therapy and other strategies outlined above could help clinicians to individualize treatment and help a greater proportion of patients to achieve long-term control of blood glucose.

Diabesity: therapeutic options

A pathogenic relationship exists between type 2 diabetes and obesity. Over the last decade, the escalation in diabetes cases has paralleled the rapid increase in obesity rates, constituting a global health crisis. Environmental risk factors attributed to the global increase in obesity include the consumption of high-calorie, high-fat foods and inadequate physical activity. Obese individuals may also have a genetic predisposition for obesity. Both diabetes and obesity confer an elevated risk of developing a range of complications and comorbidities, including cardiovascular disease, hypertension and stroke, which can complicate disease management. This review examines the aetiology of the linkages between diabetes and obesity and the range of available therapies. Recent clinical evidence substantiating the efficacy and safety of incretin-based antidiabetic therapies is analysed, in addition to data on antiobesity therapeutic strategies, such as antiobesity agents, behaviour modification and bariatric surgery. Glucose control is often accompanied by weight-neutral or modest weight reduction effects with DPP-4 inhibitor treatment (sitagliptin, vildagliptin, saxagliptin) and weight loss with GLP-1 receptor agonist therapy (exenatide, liraglutide). Studies of antiobesity agents including orlistat, sibutramine and rimonabant have shown attrition rates of 30-40%, and the long-term effects of these agents remain unknown. Bariatric surgical procedures commonly performed are laparoscopic adjustable banding of the stomach and the Roux-en-Y gastric bypass, and have produced type 2 diabetes remission rates of up to 73%. Therapeutic strategies that integrate glycaemic control and weight loss will assume greater importance as the prevalence of diabetes and obesity increase.

Effects of intensive glucose control on incidence of cardiovascular events in patients with type 2 diabetes: a meta-analysis

BACKGROUND

The effects of intensive glucose control over conventional glucose control on cardiovascular outcomes of patients with type 2 diabetes remain uncertain.

METHODS

We searched MEDLINE, EMBASE, and the Cochrane database to identify randomized controlled trials that compared the effects of intensive glucose control and conventional glucose control, on cardiovascular events in patients with type 2 diabetes.

RESULTS

Seven trials involving 34,144 participants with type 2 diabetes were included. Intensive glucose control significantly reduced major cardiovascular events by 10% (relative risk (RR) 0.90, 95% CI 0.85-0.96; P = 0.0006), and non-fatal myocardial infarction by 16% (0.84, 95% CI 0.76-0.93; P = 0.0006) at the expense of increased incidence of severe hypoglycemia (2.30, 95% CI 1.74-3.03; P < 0.00001), while all-cause mortality, cardiovascular death, non-fatal stroke, and heart failure were similar between the two groups. Subgroup analyses showed that patients with longer follow-up duration, shorter diabetic duration, less glycosylated hemoglobin (HbA1c) reduction, higher HbA1c concentration at follow-up, and lower base-line HbA1c benefited more from intensive glucose control.

CONCLUSION

An intensive glucose control strategy can effectively reduce the risk of major cardiovascular events but at the expense of a significantly increased risk of severe hypoglycemia in patients with type 2 diabetes.

Type 2 diabetes: assessing the relative risks and benefits of glucose-lowering medications

The selection of appropriate pharmacologic therapy for any disease requires a careful assessment of benefit and risk. In the case of type 2 diabetes, this decision typically balances the benefits accrued from improved glycemic control with the risks inherent in glucose-lowering medications. This review is intended to assist therapeutic decision-making by carefully assessing the potential benefit from improved metabolic control relative to the potential risks of a wide array of currently prescribed glucose-lowering agents. Wherever possible, risks and benefits have been expressed in terms of absolute rates (events per 1000 patient-years) to facilitate cross-study comparisons. The review incorporates data from new studies (Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation, Action to Control Cardiovascular Risk in Diabetes, and the Veterans Affairs Diabetes Trial), as well as safety issues associated with newer glucose-lowering medications.

Clinical experience with exenatide in a routine secondary care diabetes clinic

Exenatide use in type 2 diabetes is limited in routine clinical practice. We examined a cross-section of 90 patients. Mean weight and HBA(1c) were 114.9+/-20.6 kg, 10.3+/-2.1% at initiation; 108.0+/-15.3 kg (p<0.0001), 9.0+/-2.1% (p<0.001) at 3 months; 109.2+/-18.2 kg (p<0.0001), 9.5+/-2.3% (p=0.08) at 6 months. Exenatide appears effective in reducing HBA(1c) and weight.

Benefits of moderate weight loss in patients with type 2 diabetes

Weight loss is a primary goal of therapy in overweight patients with type 2 diabetes. This review examines whether positive patient outcomes are observed even after relatively small amounts of weight loss, that is, weight loss being more easily attainable in practice. Clinical studies demonstrate that therapeutic benefit rises with increasing weight loss, but that losses as low as 0.45-4 kg (1-9 lb) have positive effects on metabolic control, cardiovascular risk factors and mortality rates. Even the intention to lose weight, without significant success, can improve outcomes in patients with diabetes, presumably because of the healthy behaviours associated with the attempt. The current data support a continued focus on weight loss, including moderate weight loss, as a key component of good care for overweight patients with type 2 diabetes.