Beyond Glycemic Control: Treating the Entire Type 2 Diabetes Disorder

Which is better, high-dose metformin monotherapy or low-dose metformin/linagliptin combination therapy, in improving glycemic variability in type 2 diabetes patients with insufficient glycemic control despite low-dose metformin monotherapy? A randomized, cross-over, continuous glucose monitoring-based pilot study

AIMS/INTRODUCTION

The present study investigated the effect of high-dose metformin or low-dose metformin/linagliptin combination therapy on glycemic variability (GV) in type 2 diabetes patients with insufficient glycemic control despite low-dose metformin monotherapy in a cross-over study using continuous glucose monitoring.

MATERIALS AND METHODS

The present study was carried out with 11 type 2 diabetes outpatients (7% < glycated hemoglobin < 10%) receiving low-dose metformin monotherapy (500-1,000 mg). All patients were assigned to either metformin 1,500 mg monotherapy (HMET) or combination therapy of low-dose (750 mg) metformin and linagliptin 5 mg (LMET + dipeptidyl peptidase-4 [DPP4]). GV was evaluated by continuous glucose monitoring after >4 weeks of the initial treatment and again after cross-over to the other treatment. GV metrics were compared between the treatments using the Wilcoxon signed-rank test.

RESULTS

Of the continuous glucose monitoring-derived GV metrics for the HMET versus LMET + DPP4, mean glucose levels, standard deviations and mean amplitude of glucose excursions were not significantly different. Although the pre-breakfast glucose levels were not significantly different among the treatments (P = 0.248), the 3-h postprandial glucose area under the curve (>160 mg/dL) after breakfast was significantly larger with HMET versus LMET + DPP4 (9,550 [2,075-11,395] vs 4,065 [1,950-8,895]; P = 0.041).

CONCLUSIONS

A comparison of GV with HMET versus LMET + DPP4 suggested that LMET + DPP4 might reduce post-breakfast GV to a greater degree than HMET in type 2 diabetes patients receiving low-dose metformin monotherapy.

Sodium-glucose Cotransporter-2 Inhibitors: Moving Beyond the Glycemic Treatment Goal

Revelations of the multifactorial pathogenesis of type 2 diabetes mellitus (T2DM) that extend beyond the role of insulin and glucose utilization have been crucial in redefining the treatment paradigm. The focus of treatment is currently directed towards achieving wide-ranging targets encompassing the management of cardiovascular comorbidities that have been evidenced as indispensable aspects of T2DM. While most currently prescribed antihyperglycemic agents have little or no effect on reducing cardiovascular risks, some have been associated with undesirable effects on common risk factors such as weight gain and cardiovascular sequelae. Sodium-glucose cotransporter-2 inhibitors (SGLT2i) are newer additions to the array of therapeutic agents for T2DM that have demonstrated robust glycemic control as mono and add-on therapies. Their unique renal mode of action, independent of insulin modulation, confers complementary metabolic benefits. By virtue of these effects, SGLT2i may have a distinct role in the revised treatment recommendations by established working groups such as the American Diabetes Association and the American Association of Clinical Endocrinologists that advocate a more comprehensive management of T2DM, not restricting to glycemic targets. The current review gives an overview of the changing treatment needs for T2DM and discusses the nonglycemic effects of SGLT2i. It provides an updated summary on the efficacy of canagliflozin, dapagliflozin, and empagliflozin in promoting weight loss, stabilizing blood pressure, and other favorable metabolic effects.

Treat-to-target trials: uses, interpretation and review of concepts

Treat-to-target trial designs compare investigational insulins with a standard insulin. Treat-to-target trials force-titrate insulin dosages to achieve a prespecified treatment goal. With comparable glycaemic control, comparisons of safety endpoints such as hypoglycaemia can be made to establish the risk-benefit profile of the new insulin. Glargine versus NPH showed comparable A1C reductions; however, A1C <7% without associated nocturnal hypoglycaemia was reached in more patients on glargine and overall hypoglycaemia was lower. Detemir versus glargine showed non-inferiority between the groups; however, with less weight gain and more injection site reactions with detemir. Detemir/aspart versus glargine/aspart showed non-inferiority between the treatments, however, with less weight gain in the detemir group but comparable risk of hypoglycaemia. Degludec in combination with aspart versus glargine/aspart showed comparable A1C reductions. However, degludec-treated patients had less overall hypoglycaemia and less nocturnal hypoglycaemia. Because insulin titrations are guided by goal attainment with each treatment, treat-to-target trials enable clinicians to determine differences in non-glycaemic treatment effects, such as rates of hypoglycaemia and weight gain, at the same level of glycaemic control.

Continuous subcutaneous insulin infusion (CSII) pumps

Optimal blood glucose control and the restoration of the physiological insulin secretion is a current medical challenge andwill account for an overall cardiovascular morbidity and mortality related to diabetes mellitus complications. Continuous Subcutaneous Insulin Infusion (CSII) is the first step to the development of the so-called "artificial pancreas" and is intended to restore blood glucose levels and the frequency of hypoglycemic episodes. CSII using an external pump, offers both a better glycemic profile compared to multiple daily insulin injections (MDI) and a broader flexibility in everyday activities. The advantages of insulin pumps, i.e., basal delivery consistency, adjustable basal rates and low insulin depots also contribute to its reported clinical superiority. However, experience with CSII indicates that candidate patients should be carefully selected, thoroughly educated and vividly motivated to improve their blood glucose control.

Decreases in dietary glycemic index are related to weight loss among individuals following therapeutic diets for type 2 diabetes

This study assessed the effect of changes in glycemic index (GI) and load (GL) on weight loss and glycated hemoglobin (HbA1c) among individuals with type 2 diabetes beginning a vegan diet or diet following the 2003 American Diabetes Association (ADA) recommendations. The study was a 22-wk, randomized trial of 99 participants with type 2 diabetes who were counseled to follow 1 of 2 diet treatments. GI and GL changes were assessed based on 3-d dietary records. The relationships between GI/GL and changes in weight and HbA1C were calculated. In an intention-to-treat analysis (n = 99), the vegan group reduced GI to a greater extent than the ADA group (P < 0.05), but GL was reduced further in the ADA than the vegan group (P < 0.001). GI predicted changes in weight (P = 0.001), adjusting for changes in fiber, carbohydrate, fat, alcohol, energy intake, steps per day, group, and demographics, such that for every point decrease in GI, participants lost ~0.2 kg (0.44 lb). GI was not a predictor for changes in HbA1C after controlling for weight loss (P = 0.33). Weight loss was a predictor of changes in HbA1C (P = 0.047). GL was not related to weight loss or changes in HbA1C. A low-GI diet appears to be one of the determinants of success of a vegan or ADA diet in reducing body weight among people with type 2 diabetes. The reduction of body weight, in turn, was predictive of decreasing HbA1C.

Detecting pre-diabetes and the role of the pharmacist

OBJECTIVE

This study aims to use a pharmacoepidemiological approach to study the drug use of patients during the year prior to diabetes diagnosis (i.e. pre-diabetic patients) and control patients. Drug use might reveal cardiovascular, metabolic and/or endocrinological changes and help to identify indicators for active monitoring of Type 2 diabetes mellitus.

METHODS

A retrospective case-control study compared drug use of patients with a future diagnosis of diabetes (experimental patients) with patients without a diabetes diagnosis (control patients) based on community pharmacy records. An experimental patient had used oral hypoglycaemic drugs during 2005 or 2006. Experimental and control patients were matched in terms of age, gender and quarter of index date. Drugs were selected based on possible co-morbidities of diabetes. Drug use was expressed as a binary variable, indicating whether or not a patient took specific drugs. Drug use was compared between experimental patients during the year prior to diagnosis and control patients using the chi-squared test.

RESULTS

Our dataset covered 5,064 patients (1,688 experimental and 3,376 control patients). A higher probability of taking cardiovascular drugs was observed for specific subgroups of patients with pre-diabetes as compared to control patients: this trend was observed for men as well as for women, for various cardiovascular drug classes, and for different age groups (p<0.05), although it was not always statistically significant for the 29-38 age group. For each selected age and gender group, patients with pre-diabetes had a higher probability of taking a combination of a lipid-modifying agent and an antihypertensive drug than control patients (p<0.005).

CONCLUSIONS

Using community pharmacy data, this study demonstrated that age and a characteristic drug use pattern could contribute to detecting pre-diabetes. There is a potential role for community pharmacists to follow up drug indicators of patients with a view to refer high-risk people for screening by a physician.

Anti-diabetic effects of mildronate alone or in combination with metformin in obese Zucker rats

Mildronate is a cardioprotective drug, the mechanism of action of which is based on the regulation of l-carnitine concentration. We studied the metabolic effects of treatment with mildronate, metformin and a combination of the two in the Zucker rat model of obesity and impaired glucose tolerance. Zucker rats were p.o. treated daily with mildronate (200mg/kg), metformin (300 mg/kg), and a combination of both drugs for 4 weeks. Weight gain and plasma metabolites reflecting glucose metabolism were measured. The expression of peroxisome proliferator-activated receptor (PPAR)-α and PPAR-γ and target genes was measured in rat heart and liver tissues. Each treatment decreased the blood glucose concentration during the fed and fasted states by 1 to 2 mmol/l. Treatment with mildronate and metformin decreased the plasma insulin concentration by 31 and 29%, respectively, while the combination of both drugs significantly reduced fed insulin concentration by about 47%. Mildronate treatment increased the expression of PPAR-α in the heart tissue and PPAR-γ in the heart and liver tissues. In addition, treatment increased the expression of PPAR target genes in the heart, but not in the liver tissue. In contrast to monotherapy, treatment with the combination of mildronate and metformin significantly decreased weight gain by 19% and did not affect food intake. In conclusion, our results demonstrate that mildronate, an inhibitor of l-carnitine biosynthesis, improves adaptation to hyperglycemia- and hyperlipidemia-induced metabolic disturbances and increases PPAR-α activity.

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.

Encephalopathies: the emerging diabetic complications

Diabetic encephalopathies are now accepted complications of diabetes. They appear to differ in type 1 and type 2 diabetes as to underlying mechanisms and the nature of resulting cognitive deficits. The increased incidence of Alzheimer's disease in type 2 diabetes is associated with insulin resistance, hyperinsulinemia and hyperglycemia, and commonly accompanying attributes such as hypercholesterolemia, hypertension and obesity. The relevance of these disorders as to the emergence of dementia and Alzheimer's disease is discussed based on epidemiological studies. The pathobiology of accumulation of β-amyloid and tau the hallmarks of Alzheimer's disease are discussed based on experimental data. Type 1 diabetic encephalopathy is likely to increase as a result of the global increase in the incidence of type 1 diabetes and its occurrence in increasingly younger patients. Alzheimer-like changes and dementia are not prominently increased in type 1 diabetes. Instead, the type 1 diabetic encephalopathy involves learning abilities, intelligence development and memory retrieval resulting in impaired school and professional performances. The major underlying component here appears to be insulin deficiency with downstream effects on the expression of neurotrophic factors, neurotransmitters, oxidative and apoptotic stressors resulting in defects in neuronal integrity, connectivity and loss commonly occurring in the still developing brain. Recent experimental data emphasize the role of impaired central insulin action and provide information as to potential therapies. Therefore, the underlying mechanisms resulting in diabetic encephalopathies are complex and appear to differ between the two types of diabetes. Major headway has been made in our understanding of their pathobiology; however, many questions remain to be clarified. In view of the increasing incidence of both type 1 and type 2 diabetes, intensified investigations are called for to expand our understanding of these complications and to find therapeutic means by which these disastrous consequences can be prevented and modified.

Multinational Internet-based survey of patient preference for newer oral or injectable Type 2 diabetes medication

BACKGROUND

The prevalence of Type 2 diabetes mellitus continues to rise. Although glucagon-like peptide-1 (GLP-1) analog and dipeptidyl peptidase-4 (DPP-4) inhibitor medications are effective, there are differences between these products, including method of administration (injectable versus oral). The objective of this study was to examine patient preferences (and predictors of preferences) for two different medication profiles, one similar to a GLP-1 analog (liraglutide) and another similar to a DPP-4 inhibitor (sitagliptin).

METHODS

Internet survey data were collected in two waves (wave 1, n = 2402; wave 2, n = 1340) using patients from the US and Europe. Patients were presented with two hypothetical medication profiles ("drug A" and "drug B", resembling sitagliptin and liraglutide, respectively) and asked to report their preferences.

RESULTS

Most patients in wave 1 and wave 2 reported that overall they would prefer a drug with the sitagliptin-like profile (81.9% and 84.4%, respectively) over a drug with the liraglutide-like profile (18.1% and 15.6%, respectively), and >80% of patients reported that they would be able to take a drug with the sitagliptin-like profile as directed by their physician for a longer period. The likelihood of preferring the sitagliptin-like profile significantly increased as age (odds ratio [OR] = 1.02) and importance placed on method of administration (OR = 1.32) increased (P < 0.05). Although the sitagliptin-like profile was preferred by the majority of patients in all subgroups, a lower proportion of patients with obesity, with weight gain, with A1C values above target, and who exercised preferred the sitagliptin-like profile compared with those without obesity (77.0% versus 87.9%), without weight gain (77.8% versus 86.7%), with A1C values at or below target (79.0% versus 86.5%), and who did not exercise (81.6% versus 86.4%), respectively (P < 0.05).

CONCLUSIONS

This research suggests that patients (across geographies) prefer an oral medication with a profile resembling sitagliptin to an injectable medication with a profile resembling liraglutide.

Therapeutics of diabetes mellitus: focus on insulin analogues and insulin pumps

Aim. Inadequately controlled diabetes accounts for chronic complications and increases mortality. Its therapeutic management aims in normal HbA1C, prandial and postprandial glucose levels. This review discusses diabetes management focusing on the latest insulin analogues, alternative insulin delivery systems and the artificial pancreas. Results. Intensive insulin therapy with multiple daily injections (MDI) allows better imitation of the physiological rhythm of insulin secretion. Longer-acting, basal insulin analogues provide concomitant improvements in safety, efficacy and variability of glycaemic control, followed by low risks of hypoglycaemia. Continuous subcutaneous insulin infusion (CSII) provides long-term glycaemic control especially in type 1 diabetic patients, while reducing hypoglycaemic episodes and glycaemic variability. Continuous subcutaneous glucose monitoring (CGM) systems provide information on postprandial glucose excursions and nocturnal hypo- and/or hyperglycemias. This information enhances treatment options, provides a useful tool for self-monitoring and allows safer achievement of treatment targets. In the absence of a cure-like pancreas or islets transplants, artificial “closed-loop” systems mimicking the pancreatic activity have been also developed. Conclusions. Individualized treatment plans for insulin initiation and administration mode are critical in achieving target glycaemic levels. Progress in these fields is expected to facilitate and improve the quality of life of diabetic patients.