Key indices of glycaemic variability for application in diabetes clinical practice

Near normal glycaemic control in diabetes consists to target daily glucose fluctuations and quarterly HbA1c oscillations in addition to overall glucose exposure. Consequently, the prerequisite is to define simple, and mathematically undisputable key metrics for the short- and long-term variability in glucose homeostasis. As the standard deviations (SD) of either glucose or HbA1c are dependent on their means, the coefficient of variation (CV = SD/mean) should be applied instead as it that avoids the correlation between the SD and mean values. A CV glucose of 36% is the most appropriate threshold between those with stable versus labile glucose homeostasis. However, when near normal mean glucose concentrations are achieved a lower CV threshold of <27 % is necessary for reducing the risk for hypoglycaemia to a minimal rate. For the long-term variability in glucose homeostasis, a CVHbA1c < 5 % seems to be a relevant recommendation for preventing adverse clinical outcomes.

Systemic Approaches for Emission Reduction in Industrial Plants Based on Physical Accounting: Example for an Aluminum Smelter

Greenhouse gas (GHG) accounting in industrial plants usually has multiple purposes, including mandatory reporting, shareholder and stakeholder communication, developing key performance indicators (KPIs), or informing cost-effective mitigation options. Current carbon accounting systems, such as the one required by the European Union Emission Trading Scheme (EU ETS), ignore the system context in which emissions occur. This hampers the identification and evaluation of comprehensive mitigation strategies considering linkages between materials, energy, and emissions. Here, we propose a carbon accounting method based on multilevel material flow analysis (MFA), which aims at addressing this gap. Using a Norwegian primary aluminum production plant as an example, we analyzed the material stocks and flows within this plant for total mass flows of goods as well as substances such as aluminum and carbon. The results show that the MFA-based accounting (i) is more robust than conventional tools due to mass balance consistency and higher granularity, (ii) allows monitoring the performance of the company and defines meaningful KPIs, (iii) can be used as a basis for the EU ETS reporting and linked to internal reporting, (iv) enables the identification and evaluation of systemic solutions and resource efficiency strategies for reducing emissions, and (v) has the potential to save costs.

Insulin Centennial: Milestones influencing the development of insulin preparations since 1922

During 1921 to 1922, a team effort by Banting, Macleod, Collip and Best isolated and purified insulin and demonstrated its life-giving properties, giving rise to the birth of insulin therapy. In the early years (1922-1950), priorities revolved around the manufacture of insulin to meet demand, improving purity to avoid allergic reactions, establishing insulin standards and increasing its duration of action to avoid multiple daily injections. Shortly after the emergence of insulin, Joslin and Allen advocated the need to achieve and maintain good glycaemic control to realize its full potential. Although this view was opposed by some during a dark period in the history of insulin, it was subsequently endorsed some 60 years later endorsed by the Diabetes Control and Complications Trial and United Kingdom Prospective Diabetes Study. Major scientific advances by the Nobel Laureates Sanger, Hodgkin, Yalow and Gilbert and also by Steiner have revolutionized the understanding of diabetes and facilitated major advances in insulin therapy. The more recent advent of recombinant technology over the last 40 years has provided the potential for unlimited source of insulin, and the ability to generate various insulin 'analogues', in an attempt to better replicate normal insulin secretory patterns. The emerging biosimilars now provide the opportunity to improve availability at a lower cost.

The obesity treatment dilemma: Why dieting is both the answer and the problem? A mechanistic overview

Restricted-calorie diets are the most worldwide used treatments for obesity. Although such strategies are based on the first law of thermodynamics, the real life clinical practice demonstrates that the observed weight losses are divergent from those theoretically predicted. Loosely adherence to recommendations is one of the main causes for the limited efficacy of dieting, but many additional factors can be involved in the hurdles to weight loss. According to the second law of thermodynamics any restriction in dietary energy intake results in energy sparing with a diminution in the basal metabolic rate and a concomitant loss in the lean body mass. This "thrifty" energetic adaptation is associated with a progressive reduction in the difference between levels of energy intake and expenditure, thus resulting in a drastic fall in weight loss rates on the medium and long-term regardless of the dietary carbohydrate/fat ratio. This loss of efficacy is aggravated by the misadaptation of the production and action of anti-obesity hormones such as leptin. During the latest past decades the discovery of changes in the gut microbiota of obese people referred to as "obese dysbiosis" has raised the question as to whether these alterations can participate to diet-resistance. Combined with the behavioral and psychological barriers to low-calorie diets, there is a broad physiologic spectrum of evidence indicating that weight loss is a hard challenge. Consequently, the answer would be primarily to prevent the development of obesity and at worst to avoid its ominous progression from metabolically healthy to unhealthy stages.

Review of methods for detecting glycemic disorders

Prediabetes (intermediate hyperglycemia) consists of two abnormalities, impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) detected by a standardized 75-gram oral glucose tolerance test (OGTT). Individuals with isolated IGT or combined IFG and IGT have increased risk for developing type 2 diabetes (T2D) and cardiovascular disease (CVD). Diagnosing prediabetes early and accurately is critical in order to refer high-risk individuals for intensive lifestyle modification. However, there is currently no international consensus for diagnosing prediabetes with HbA1c or glucose measurements based upon American Diabetes Association (ADA) and the World Health Organization (WHO) criteria that identify different populations at risk for progressing to diabetes. Various caveats affecting the accuracy of interpreting the HbA1c including genetics complicate this further. This review describes established methods for detecting glucose disorders based upon glucose and HbA1c parameters as well as novel approaches including the 1-hour plasma glucose (1-h PG), glucose challenge test (GCT), shape of the glucose curve, genetics, continuous glucose monitoring (CGM), measures of insulin secretion and sensitivity, metabolomics, and ancillary tools such as fructosamine, glycated albumin (GA), 1,5- anhydroglucitol (1,5-AG). Of the approaches considered, the 1-h PG has considerable potential as a biomarker for detecting glucose disorders if confirmed by additional data including health economic analysis. Whether the 1-h OGTT is superior to genetics and omics in providing greater precision for individualized treatment requires further investigation. These methods will need to demonstrate substantially superiority to simpler tools for detecting glucose disorders to justify their cost and complexity.

Respective Contributions of Glycemic Variability and Mean Daily Glucose as Predictors of Hypoglycemia in Type 1 Diabetes: Are They Equivalent?

OBJECTIVE

To evaluate the respective contributions of short-term glycemic variability and mean daily glucose (MDG) concentration to the risk of hypoglycemia in type 1 diabetes.

RESEARCH DESIGN AND METHODS

People with type 1 diabetes (n = 100) investigated at the University Hospital of Montpellier (France) underwent continuous glucose monitoring (CGM) on two consecutive days, providing a total of 200 24-h glycemic profiles. The following parameters were computed: MDG concentration, within-day glycemic variability (coefficient of variation for glucose [%CV]), and risk of hypoglycemia (presented as the percentage of time spent below three glycemic thresholds: 3.9, 3.45, and 3.0 mmol/L).

RESULTS

MDG was significantly higher, and %CV significantly lower (both P < 0.001), when comparing the 24-h glycemic profiles according to whether no time or a certain duration of time was spent below the thresholds. Univariate regression analyses showed that MDG and %CV were the two explanatory variables that entered the model with the outcome variable (time spent below the thresholds). The classification and regression tree procedure indicated that the predominant predictor for hypoglycemia was %CV when the threshold was 3.0 mmol/L. In people with mean glucose ≤7.8 mmol/L, the time spent below 3.0 mmol/L was shortest (P < 0.001) when %CV was below 34%.

CONCLUSIONS

In type 1 diabetes, short-term glycemic variability relative to mean glucose (i.e., %CV) explains more hypoglycemia than does mean glucose alone when the glucose threshold is 3.0 mmol/L. Minimizing the risk of hypoglycemia requires a %CV below 34%.

Outcomes of vaginal squamous cell carcinoma of patients treated with radiation therapy: a series of 37 patients from a single expert center

INTRODUCTION

The aim is to assess the outcome of patients treated for vaginal carcinoma with radiation therapy in terms of long-term tolerance and survival.

MATERIALS AND METHODS

This single-center retrospective study included patients with squamous cell carcinoma of the vagina treated with pelvic external beam radiation therapy (EBRT) with or without vaginal brachytherapy (VB) between 1990 and 2013.

RESULTS

Thirty-seven patients were included with stage I (24%), II (60%), III (8%), or IV (8%) vaginal tumors. Median age was 66 years (range 27-86 years). Median tumor size was 4 cm (range 0.7-12 cm). Seven patients underwent first intention surgery. The 37 patients received pelvic EBRT (45 Gy) with inguinal irradiation in 57% of cases. Fifteen (41%) received concurrent chemotherapy. Low-dose supplemental VB was performed in 31 patients (84%) (median dose: 20 Gy). Median follow-up was 59 months (range 7-322 months). Four patients (11%) had late grade 3-4 complications. Relapse occurred in 11 patients (30%), five of them locally. The 5-year relapse-free and cancer-specific survival rates were 68% and 76%, respectively. Surgery and concurrent chemotherapy did not seem to have an impact on the course of the disease.

CONCLUSION

In our experience, pelvic EBRT leads to prolonged survival with acceptable long-term toxicity in patients with squamous cell carcinoma of the vagina.

Glycaemic variability in diabetes: clinical and therapeutic implications

Glycaemic variability is an integral component of glucose homoeostasis. Although it has not yet been definitively confirmed as an independent risk factor for diabetes complications, glycaemic variability can represent the presence of excess glycaemic excursions and, consequently, the risk of hyperglycaemia or hypoglycaemia. Glycaemic variability is currently defined by a large and increasing number of metrics, representing either short-term (within-day and between-day variability) or long-term glycaemic variability, which is usually based on serial measurements of HbA_1c or other measures of glycaemia over a longer period of time. In this Review, we discuss recent evidence examining the association between glycaemic variability and diabetes-related complications, as well as non-pharmacological and pharmacological strategies currently available to address this challenging aspect of diabetes management.

Branched-Chain Amino Acid Database Integrated in MEDIPAD Software as a Tool for Nutritional Investigation of Mediterranean Populations

Branched-chained amino acids (BCAA) are essential dietary components for humans and can act as potential biomarkers for diabetes development. To efficiently estimate dietary intake, we developed a BCAA database for 1331 food items found in the French Centre d'Information sur la Qualité des Aliments (CIQUAL) food table by compiling BCAA content from international tables, published measurements, or by food similarity as well as by calculating 267 items from Greek, Turkish, Romanian, and Moroccan mixed dishes. The database embedded in MEDIPAD software capable of registering 24 h of dietary recalls (24HDR) with clinical and genetic data was evaluated based on archived 24HDR of the Saint Pierre Institute (France) from 2957 subjects, which indicated a BCAA content up to 4.2 g/100 g of food and differences among normal weight and obese subjects across BCAA quartiles. We also evaluated the database of 119 interviews of Romanians, Turkish and Albanians in Greece (27⁻65 years) during the MEDIGENE program, which indicated mean BCAA intake of 13.84 and 12.91 g/day in males and females, respectively, comparable to other studies. The MEDIPAD is user-friendly, multilingual, and secure software and with the BCAA database is suitable for conducting nutritional assessment in the Mediterranean area with particular facilities for food administration.

The application of simple metrics in the assessment of glycaemic variability

The assessment of glycaemic variability (GV) remains a subject of debate with many indices proposed to represent either short- (acute glucose fluctuations) or long-term GV (variations of HbA_1c). For the assessment of short-term within-day GV, the coefficient of variation for glucose (%CV) defined as the standard deviation adjusted on the 24-h mean glucose concentration is easy to perform and with a threshold of 36%, recently adopted by the international consensus on use of continuous glucose monitoring, separating stable from labile glycaemic states. More complex metrics such as the Low Blood Glucose Index (LBGI) or High Blood Glucose Index (HBGI) allow the risk of hypo or hyperglycaemic episodes, respectively to be assessed although in clinical practice its application is limited due to the need for more complex computation. This also applies to other indices of short-term intraday GV including the mean amplitude of glycemic excursions (MAGE), Shlichtkrull's M-value and CONGA. GV is important clinically as exaggerated glucose fluctuations are associated with an enhanced risk of adverse cardiovascular outcomes due primarily to hypoglycaemia. In contrast, there is at present no compelling evidence that elevated short-term GV is an independent risk factor of microvascular complications of diabetes. Concerning long-term GV there are numerous studies supporting its association with an enhanced risk of cardiovascular events. However, this association raises the question as to whether the impact of long-term variability is not simply the consequence of repeated exposure to short-term GV or ambient chronic hyperglycaemia. The renewed emphasis on glucose monitoring with the introduction of continuous glucose monitoring technologies can benefit from the introduction and application of simple metrics for describing GV along with supporting recommendations.

A review of glucagon-like peptide-1 receptor agonists and their effects on lowering postprandial plasma glucose and cardiovascular outcomes in the treatment of type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is an independent risk factor for cardiovascular (CV) comorbidities, with CV disease being the most common cause of death in adults with T2DM. Although glucocentric therapies may improve glycaemic control (as determined by glycated haemoglobin levels), evidence suggests that this approach alone has limited beneficial effects on CV outcomes relative to improvements in lipid and blood pressure control. This may be explained in part by the fact that current antidiabetic treatment regimens primarily address overall glycaemia and/or fasting plasma glucose, but not the postprandial plasma glucose (PPG) excursions that have a fundamental causative role in increasing CV risk. This literature review evaluates the relationship between PPG and the risk of CV disease, discusses the treatment of T2DM with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and examines the associated CV outcomes. The literature analysis suggests that exaggerated PPG excursions are a risk factor for CV disease because of their adverse pathophysiologic effects on the vasculature, resulting in increased all-cause and CV-related mortality. Although GLP-1 RAs are well established in the current T2DM treatment paradigm, a subgroup of these compounds has a particularly pronounced, persistent and short-lived effect on gastric emptying and, hence, lower PPG substantially. However, current long-term data on CV outcomes with GLP-1 RAs are contradictory, with both beneficial and adverse effects having been reported. This review explores the opportunity to direct treatment towards controlling PPG excursions, thereby improving not only overall glycaemic control but also CV outcomes.

Future challenges and therapeutic opportunities in type 2 diabetes: Changing the paradigm of current therapy

Most algorithms for type 2 diabetes mellitus (T2DM) do not recommend treatment escalation until glycated haemoglobin (HbA1c) fails to reach the recommended target of 7% (53 mmol/mol) within approximately 3 months on any treatment regimen ("treat to failure"). Clinical inertia and/or poor adherence to therapy contribute to patients not reaching glycaemic targets when managed according to this paradigm. Clinical inertia exists across the entire spectrum of anti-diabetes therapies, although it is most pronounced when initiating and optimizing insulin therapy. Possible reasons include needle aversion, fear of hypoglycaemia, excessive weight gain and/or the need for increased self-monitoring of blood glucose. Studies have suggested, however, that early intensive insulin therapy in newly diagnosed, symptomatic patients with T2DM with HbA1c >9% (75 mmol/mol) can preserve beta-cell function, thereby modulating the disease process. Furthermore, postprandial plasma glucose is a key component of residual dysglycaemia, evident especially when HbA1c remains above target despite fasting normoglycaemia. Therefore, to achieve near normoglycaemia, additional treatment with prandial insulin or a glucagon-like peptide-1 receptor agonist (GLP-1 RA) is often required. Long- or short-acting GLP-1 RAs offer effective alternatives to basal or prandial insulin in patients inadequately controlled with other therapies or basal insulin alone, respectively. This review highlights the limitations of current algorithms, and proposes an alternative based on the early introduction of insulin therapy and the rationale for the sequential or fixed combination of GLP-1 RAs with insulin ("treat-to-success" paradigm).

Toward Defining the Threshold Between Low and High Glucose Variability in Diabetes

OBJECTIVE

To define the threshold for excess glucose variability (GV), one of the main features of dysglycemia in diabetes.

RESEARCH DESIGN AND METHODS

A total of 376 persons with diabetes investigated at the University Hospital of Montpellier (Montpellier, France) underwent continuous glucose monitoring. Participants with type 2 diabetes were divided into several groups-groups 1, 2a, 2b, and 3 (n = 82, 28, 65, and 79, respectively)-according to treatment: 1) diet and/or insulin sensitizers alone; 2) oral therapy including an insulinotropic agent, dipeptidyl peptidase 4 inhibitors (group 2a) or sulfonylureas (group 2b); or 3) insulin. Group 4 included 122 persons with type 1 diabetes. Percentage coefficient of variation for glucose (%CV = [(SD of glucose)/(mean glucose)] × 100) and frequencies of hypoglycemia (interstitial glucose <56 mg/dL [3.1 mmol/L]) were computed.

RESULTS

Percentages of CV (median [interquartile range]; %) increased significantly (P < 0.0001) from group 1 (18.1 [15.2-23.9]) to group 4 (37.2 [31.0-42.3]). In group 1, the upper limit of %CV, which served as reference for defining excess GV, was 36%. Percentages of patients with %CVs above this threshold in groups 2a, 2b, 3, and 4 were 0, 12.3, 19.0, and 55.7%, respectively. Hypoglycemia was more frequent in group 2b (P < 0.01) and groups 3 and 4 (P < 0.0001) when subjects with a %CV >36% were compared with those with %CV ≤36%.

CONCLUSIONS

A %CV of 36% appears to be a suitable threshold to distinguish between stable and unstable glycemia in diabetes because beyond this limit, the frequency of hypoglycemia is significantly increased, especially in insulin-treated subjects.

Individualized, patient-centered use of lixisenatide for the treatment of type 2 diabetes mellitus

INTRODUCTION

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease associated with hyperglycemia, which can lead to serious vascular complications. Current treatment guidelines place particular emphasis on personalization of therapy. Within this guidance, the use of various second-line therapies, including glucagon-like peptide-1 receptor agonists (GLP-1 RAs), is recommended under certain circumstances. Areas covered: Factors influencing glucose homeostasis, including gastric emptying and the associated cardiovascular (CV) risk when homeostasis is not maintained, are reviewed. Physiology relating to the mechanism of action of GLP-1 RAs is summarized, with a particular focus on lixisenatide. In addition, an overview of efficacy and safety data for lixisenatide is presented and the CV effects of GLP-1 RAs are examined. Finally, the rationale and clinical data supporting the combination of lixisenatide and basal insulin are explored. Expert opinion: GLP-1 analogs meet a need for better glycemic control, with the added benefits of reduced hypoglycemic risk and body weight. The combination of a short-acting GLP-1 RA, such as lixisenatide, with a basal insulin, exploits the complementary effects of both of these therapies and seems well suited for the treatment of T2DM. However, further studies are needed to establish the associated CV risks and/or benefits of GLP-1 RAs.

Early Treatment with Basal Insulin Glargine in People with Type 2 Diabetes: Lessons from ORIGIN and Other Cardiovascular Trials

Dysglycemia results from a deficit in first-phase insulin secretion compounded by increased insulin insensitivity, exposing β cells to chronic hyperglycemia and excessive glycemic variability. Initiation of intensive insulin therapy at diagnosis of type 2 diabetes mellitus (T2DM) to achieve normoglycemia has been shown to reverse glucotoxicity, resulting in recovery of residual β-cell function. The United Kingdom Prospective Diabetes Study (UKPDS) 10-year post-trial follow-up reported reductions in cardiovascular outcomes and all-cause mortality in persons with T2DM who initially received intensive glucose control compared with standard therapy. In the cardiovascular outcome trial, outcome reduction with an initial glargine intervention (ORIGIN), a neutral effect on cardiovascular disease was observed in the population comprising prediabetes and T2DM. Worsening of glycemic control was prevented over the 6.7 year treatment period, with few serious hypoglycemic episodes and only moderate weight gain, with a lesser need for dual or triple oral treatment versus standard care. Several other studies have also highlighted the benefits of early insulin initiation as first-line or add-on therapy to metformin. The decision to introduce basal insulin to metformin must, however be individualized based on a risk-benefit analysis. The landmark ORIGIN trial provides many lessons relating to the concept and application of early insulin therapy for the prevention and safe and effective induction and maintenance of glycemic control in type 2 diabetes.

FUNDING

Sanofi.

Near normal HbA1c with stable glucose homeostasis: the ultimate target/aim of diabetes therapy

Achieving near normal glucose homeostasis implies that all components of dysglycemia that are present in diabetes states be eliminated. Reducing ambient/overall hyperglycemia is a pre-requisite to eliminate the risk of development and progression of diabetes complications. More controversially however, are the relative and related contributions of postprandial glucose excursions, glucose variability, hypoglycemia and the dawn phenomenon across the spectrum of dysglycemia. For instance, it is likely that the dawn phenomenon contributes to ambient hyperglycemia and that postprandial glucose excursions are at the cross road of ambient hyperglycemia and glucose variability with glucose fluctuations as causative risk factors for hypoglycemia. Proof-of-concept trials such as the ongoing FLAT-SUGAR study are necessary for gaining further insight into the possible harmful effects of some of these features such as excessive glycemic variability and glucose excursions, still considered to be of minor relevance by several diabetologists. Whether their role will be more thoroughly proven through further intervention trials with "hard" endpoints, remains to be seen. In the meantime more consideration should be given to medications aimed at concomitantly reducing ambient/overall hyperglycemia and those additional abnormal glycemic features of dysglycemia.

Ramadan and diabetes: What we see, learn and understand from continuous glucose monitoring

Abstinence from eating and drinking from dawn to sunset characterizes the holy month of Ramadan. For the 50 million Muslims worldwide with diabetes who adhere to this religious fast, the practice results in marked changes in glucose homoeostasis. The sunset meal (Iftar) that breaks the fasting state is followed by exaggerated surges in blood glucose and sustained overnight hyperglycaemia in cases of nocturnal overfeeding. The predawn meal (Suhoor) frequently results in prolonged glucose decay over the daylight hours. These glycaemic disturbances are particularly marked in insulin-treated patients, in those with unsatisfactory diabetes control during the pre-Ramadan period and in patients who are poorly compliant with lifestyle recommendations. Whether such patients should be exempt from the Islamic fast remains an open debate, which might be partially resolved by long-term controlled studies using the technology of continuous glucose monitoring in large populations of patients with diabetes.

"Mild dysglycemia" in type 2 diabetes: to be neglected or not?

"Mild dysglycemia" in type 2 diabetes can be defined by the range of HbA1c levels≥6.5% (48 mmol/mol) and<7% (53 mmol/mol), which corresponds to when the risk for vascular complications begins to increase. This "mild dysglycemia" is characterized by both a dawn phenomenon (a spontaneous blood glucose rise in the early morning) and an excess of post-prandial glucose excursions in the absence of abnormal elevation in basal glucose, especially during nocturnal periods. This represents an intermediary stage between pre-diabetes (HbA1c≥5.7%, 39 mmol/mol, and<6.5%, 48 mmol/mol) and those who begin to show a steadily progressive worsening in basal glucose (HbA1c≥7%, 53 mmol/mol). Should this relatively minor intermediate dysglycemic phase deserve more attention, that is the question. The now available incretin-based therapies, and more specifically the DPP-4 inhibitors provide the clinician with the possibility to reduce or eradicate both the dawn phenomenon and post-meal glucose excursions with minimal side effects. The availability of 24-h glycemic profiles in those with "mild dysglycemia" will help to describe their individual glycemic phenotype, based on which the early and appropriate life style changes and/or pharmacological interventions can be introduced.

Residual dysglycemia when at target HbA(1c) of 7% (53mmol/mol) in persons with type 2 diabetes

AIMS

To understand the composition of the residual dysglycemia when HbA1c is between 6.5% (48mmol/mol) and 7% (53mmol/mol), representing the definition of diabetes and the recommended treatment goal, respectively.

METHODS

One hundred persons with type 2 diabetes and a HbA1c<7% (53mmol/mol), treated with diet alone and/or oral hypoglycemic agents underwent continuous glucose monitoring (CGM) and were further divided into two subgroups 1 (n=50) and 2 (n=50) according to whether the HbA1c was <6.5% (48mmol/mol) or 6.5-6.9% (48-52mmol/mol), respectively. A similar analysis was performed in those on diet alone: subgroups A (n=34, HbA1c<6.5%, 48mmol/mol) and B (n=10, HbA1c 6.5-6.9%, 48-52mmol/mol). The residual dysglycemia determined from the CGM was assessed using glucose exposures defined as areas under curves (AUCs) and mean glucose values.

RESULTS

Averaged 2-h postprandial glucose value (averaged PPG, mmol/L, mean±SD) and postprandial glucose exposure (AUCpp, mean±SD, mmol·L(-1)·h) were significantly higher in subgroup 2 (mean HbA1c=6.7%, 50mmol/mol) than in subgroup 1 (mean HbA1c=6.0%, 42mmol/mol): averaged PPG=8.1±1.3 versus 7.3±1.3mmol/L (p<0.002); AUCpp=23.5±8.6 versus 16.2±8.6 (p<0.0001). The percentages of persons with averaged PPG≥7.8mmol/L were 52% and 24% (p<0.01) in subgroups 2 and 1, respectively. Similar results were observed in those (subgroups A and B) who were on diet alone.

CONCLUSIONS

The residual dysglycemia in type 2 diabetes with HbA1c between 6.5 and 6.9% (48-52mmol/mol) inclusive is mainly due to remnant abnormal postprandial glucose excursions. Consequently, HbA1c<6.5% (48mmol/mol) is an achievable goal with therapeutic measures aimed at reducing postmeal glucose when the HbA1c is at 7% (53mmol/mol).

Self-monitoring of blood glucose: a prerequisite for diabetes management in outcome trials

Evidence for the value of self-monitoring of blood glucose (SMBG) with regard to the achievement of treatment targets, detection of postprandial glucose excursions, and minimization of glycemic variability is increasing. In large clinical trials, SMBG is a key component for the optimization of diabetes treatment in insulin-treated diabetes. It also plays an essential role in outcome studies. However, details of SMBG use in both the methods and results sections of clinical articles are frequently scarce. Also, a discussion of the SMBG data and its impact on insulin therapy is valuable. In the recently completed Outcome Reduction with an Initial Glargine INtervention (ORIGIN) trial, SMBG was described in detail and insulin titration was largely driven by SMBG. Both aspects largely contributed to the fact that near-normal control was achieved over a long-term period.

Basal insulin analogues in the management of diabetes mellitus: What progress have we made?

Insulin remains the most effective and consistent means of controlling blood glucose levels in diabetes. Since 1946, neutral protamine Hagedorn (NPH) has been the predominant basal insulin in clinical use. However, absorption is variable due to the need for resuspension and the time-action profile (peak activity 4-6 h after subcutaneous administration) confers an increased propensity for between-meal and nocturnal hypoglycaemia. In the 1980s, recombinant DNA technology enabled modifications to the insulin molecule resulting in the soluble long-acting insulin analogues, glargine and detemir. Both exhibit a lower risk of hypoglycaemia compared with neutral protamine Hagedorn due to improved time-action profiles and reduced day-to-day glucose variability. Glargine is indicated for administration once daily and detemir once or twice daily. Degludec is the latest prolonged-acting insulin which forms long subcutaneous multi-hexamers that delay absorption. Recent phase III trials in type 1 and type 2 diabetes show that degludec was non-inferior to comparators (predominantly glargine) with a minimal although inconsistent reduction in overall hypoglycaemia and a small absolute difference in nocturnal hypoglycaemia. Newer developmental agents include LY2605541 and glargine U300. LY2605541 comprises insulin lispro combined with polyethylene glycol, thereby increasing its hydrodynamic size and retarding absorption from the subcutaneous tissue. Glargine U300 is a new formulation of glargine resulting in a flatter and more prolonged time-action profile than its predecessor. This article reviews recent advances in basal insulin analogues, including a critical appraisal of the degludec trials.

[Isolated pelvic recurrences of cervical carcinoma treated with salvage chemoradiotherapy]

PURPOSE

Evaluation of the results of salvage radiation therapy with curative intent in the treatment of recurrent cervical carcinoma.

PATIENTS AND METHODS

Fourteen patients with a recurrence of a cervical cancer were treated in our department between 1982 and 2009. Five patients had a pelvic relapse, four a vaginal relapse and five a pelvic lymph node relapse. Four patients had first a surgical resection of the relapse, which was incomplete in two patients. All patients had pelvic radiotherapy with a median dose of 55Gy in conventional fractionation. Concurrent chemotherapy was administered to 12 patients. A vaginal brachytherapy with a median dose of 20Gy was performed in addition in 3 patients. The median follow-up was 39months.

RESULTS

Safety of radiation therapy was correct with 29% of grade 3 acute or intestinal toxicity. Tumor control was observed in 10 patients (71%). Four patients presented a locoregional tumor progression. At the time of analysis, three patients had died from their cancer. From the date of relapse, the rate of overall survival at 2 and 5year was respectively 84% and 74%. Three patients (21%) had severe late effects.

CONCLUSION

In our experience, chemoradiotherapy can achieve a high rate of remission in patients with isolated pelvic recurrence of cervical cancer. This treatment is feasible only if the patient had not received radiation therapy before or if the relapse is out of the previously irradiated volume.

Magnitude of the dawn phenomenon and its impact on the overall glucose exposure in type 2 diabetes: is this of concern?

OBJECTIVE

To assess the magnitude of the dawn phenomenon and its impact on the total glucose exposure in type 2 diabetes.

RESEARCH DESIGN AND METHODS

A total of 248 noninsulin-treated persons with type 2 diabetes who underwent continuous glucose monitoring were divided into three groups selected by treatments: diet alone (n = 53); insulin sensitizers alone (n = 82); and insulin secretagogues alone or in combination with insulin sensitizers (n = 113). The dawn phenomenon (∂ glucose, mg/dL) was quantified by its absolute increment from nocturnal nadir to prebreakfast value. The participants were secondarily divided into two paired subsets after they had been separated by the presence/absence of a dawn phenomenon based on a threshold of 20 mg/dL and matched for glucose nadir. The impact of the dawn phenomenon was assessed on HbA1c and 24-h mean glucose.

RESULTS

The median of ∂ glucose (interquartile range) was 16.0 (0-31.5 mg/dL) in the 248 subjects, and no differences were observed across groups selected by HbA1c or treatments. In the overall population, the mean impacts on HbA1c and 24-h mean glucose were 4.3 ± 1.3 mmol/mol (0.39 ± 0.12%) and 12.4 ± 2.4 mg/dL, respectively. The mean impact on 24-h mean glucose was not statistically different between those on diet alone (16.7 ± 5.9 mg/dL) compared with the two subsets treated with oral hypoglycemic agents (11.2 ± 5.3 and 8.5 ± 7.5 mg/dL).

CONCLUSIONS

The impact of the dawn phenomenon on overall glycemic control in type 2 diabetes, as depicted by the HbA1c level, was ∼0.4% and not eliminated by any of the currently available armamentarium of oral antidiabetes agents.

Differential effects of GLP-1 receptor agonists on components of dysglycaemia in individuals with type 2 diabetes mellitus

Metabolic consequences of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are the result of enhanced glucose-stimulated insulin secretion, inhibition of glucagon release, delayed gastric emptying and increased satiety. These attributes make GLP-1 agonists a treatment option in type 2 diabetes mellitus (T2DM). To optimise treatment choice, a detailed understanding of the effects of GLP-1 RAs on glucose homeostasis in individuals with T2DM is necessary. Although the various GLP-1 RAs share the same basic mechanisms of action, differences in pharmacokinetic/pharmacodynamic characteristics translate into differential effects on parameters of glycaemia. Head-to-head comparisons between long-acting non-prandial (liraglutide once daily and exenatide once weekly) and shorter-acting prandial (exenatide twice daily and lixisenatide once daily prandial) GLP-1 RAs confirm their differential effects on fasting plasma glucose (FPG) and post-prandial glucose (PPG). Liraglutide once daily and exenatide once weekly demonstrate greater reductions in FPG but lesser impacts on PPG excursions plasma than exenatide twice daily. Prandial GLP-1 RAs have a profound effect on post-prandial glycaemia, mediated by delaying gastric emptying, which is not subject to the tachyphylaxis occurring due to the sustained elevated plasma GLP-1 concentrations after treatment with long-acting GLP-1 RAs. Lixisenatide once-daily prandial, in contrast to liraglutide, strongly suppresses post-prandial glucagon secretion, further contributing to the more pronounced PPG-lowering effect found with lixisenatide. Evidence suggests that the GLP-1 RAs that predominantly target the prandial glucose excursions, such as exenatide twice daily and lixisenatide once-daily prandial, are therefore best used as combination therapy with basal insulin and will form an important new treatment option for individuals with T2DM.

Insulin and atherosclerosis: how are they related?

The relationship between insulin and atherosclerosis is complex. People with type 2 diabetes are affected by three main glycaemic disorders: chronic hyperglycaemia; glycaemic variability; and iatrogenic hypoglycaemia. In addition to this triumvirate, the diabetic condition is characterized by lipid disorders, chronic low-grade inflammation and activation of oxidative stress. All these associated disorders reflect the insulin-resistant nature of type 2 diabetes and contribute to the development and progression of cardiovascular (CV) diseases. By both lowering plasma glucose and improving the lipid profile, insulin exerts beneficial effects on CV outcomes. In addition, insulin has several pleiotropic effects such as anti-inflammatory, antithrombotic and antioxidant properties. Insulin per se exerts an inhibitory effect on the activation of oxidative stress and seems able to counteract the pro-oxidant effects of ambient hyperglycaemia and glycaemic variability. However, insulin actions remain a subject of debate with respect to the risk of adverse CV events, which can increase in individuals exposed to high insulin doses. Evidence from the large-scale, long-term ORIGIN trial suggests that early implementation of insulin supplementation therapy in the course of glycaemic disorders, including type 2 diabetes, has a neutral impact on CV outcomes compared with standard management. Thus, the answer to the question "What impact does insulin have on atherosclerosis?" remains unclear, even though it is logical to deduce that insulin should be initiated as soon as possible and that small doses of insulin early on are better than higher doses later in the disease process.

Frequency and severity of the dawn phenomenon in type 2 diabetes: relationship to age

OBJECTIVE

To know whether age has an independent effect on the dawn phenomenon in noninsulin-using type 2 diabetes.

RESEARCH DESIGN AND METHODS

Eighty-one individuals with type 2 diabetes were matched for HbA(1c) and divided by age into three subgroups of 27 individuals (1: ≥70 years; 2: 60-69 years; and 3: ≤59 years). All underwent ambulatory continuous glucose monitoring for quantifying the dawn phenomenon (i.e., the absolute [∂G, mg/dL] or relative [∂G%] increments from nocturnal nadirs to prebreakfast time points).

RESULTS

HbA(1c) levels and 24-h glycemic profiles were similar across the three groups. Glucose increments (mean ± SEM) were identical in the three groups: ∂G (mg/dL), 22.0 ± 4.7 (1), 21.3 ± 3.6 (2), and 18.0 ± 3.6 (3) and δG (%), 19.9 ± 4.9 (1), 21.6 ± 4.4 (2), and 17.6 ± 4.2 (3). Using the most common definition (∂G >10 mg/dL), the prevalence of the dawn phenomenon was 52, 70, and 59% in groups 1, 2, and 3, respectively.

CONCLUSIONS

The dawn phenomenon is present in the elderly.

Add-on therapies to metformin in type 2 diabetes: what modulates the respective decrements in postprandial and basal glucose?

BACKGROUND

Oral hypoglycemic agents (OHAs) are usually divided into postprandial and basal drugs. As their actions are probably more complex, it is important to ascertain which factors can modulate their effects.

SUBJECTS AND METHODS

Thirty-one type 2 diabetes patients treated with metformin (glycosylated hemoglobin [HbA1c] 6.5-9%; median, 7.3%) and enrolled in two randomized controlled studies were allocated to either rosiglitazone (Group 1, n = 8) or glimepiride (Group 2, n = 7) and to either vildagliptin or sitagliptin (Group 3 considered as a whole, n = 16). All patients were investigated using continuous glucose monitoring at baseline and after 8-12 weeks of add-on therapy. Areas under the 24-h glycemic profile curves (AUCs) were determined for assessing postprandial (AUCpp), basal (AUCb), and total (AUCtotal) hyperglycemia. After calculation of decrements in AUCs (∂AUCs) from baseline to end of treatment periods, the following contribution ratios of postprandial and basal decrements to the overall glucose decrement were determined: ∂AUCpp/∂AUCtotal and ∂AUCb/∂AUCtotal (%).

RESULTS

∂AUCpp/∂AUCtotal and ∂AUCb/∂AUCtotal were negatively and positively, respectively, associated (R(2) = 0.195, P = 0.013) with baseline HbA1c. ∂AUCpp/∂AUCtotal was significantly higher (50.8 ± 4.8%) in patients with HbA1c <7.3% than in those with HbA1c ≥ 7.3% (27.0 ± 4.4%) (P = 0.001). After adjustment on baseline HbA1c, ∂AUCpp/∂AUCtotal was greater in Group 3 (44.0 ± 1.6%) than in Group 1 (32.1 ± 4%) and 2 (37.0 ± 3.1%) (P = 0.007).

CONCLUSIONS

Gliptins, glitazones and sulfonylureas concomitantly act on basal and postprandial glucose even though gliptins are more efficient on postprandial glucose. HbA1c appears as a reliable factor for predicting the respective decrements of these two parameters and thus for guiding the choice between the aforementioned drugs.

The glycemic triumvirate and diabetic complications: is the whole greater than the sum of its component parts?

The dysglycemia of diabetes mellitus can be depicted as the glycemic triumvirate with its 3 main components: the sustained chronic (ambient) hyperglycemia, glucose variability and hypoglycemic episodes. The respective contributions of these glycemic disorders to the overall risk for diabetic complications remain a subject of debate. At present, there is cogent evidence for the direct deleterious effect of ambient hyperglycemia while the roles exerted by glucose variability and hypoglycemia remain less documented and only based on observational and pathophysiological studies. In addition, these 3 glycemic disorders could be regarded as components of either an additive or an initiator/accelerator model according to whether each disorder exerts an independent or inter-dependent effect on the development and progression of diabetes-related complications, respectively. In the present review, pros and cons arguments for each model are debated. However it is highly likely that these 3 glycemic disorders have both direct (spoke in a wheel) and indirect (link in a chain) causal effects on clinical cardiovascular outcomes. As a consequence, the relationship between the so-called glycemic triumvirate and diabetic complications might be summarized by the famous Aristotle's aphorism: "the whole is greater than the sum of its parts".