Survival as a function of HbA(1c) in people with type 2 diabetes: a retrospective cohort study

Screening for type 2 diabetes: an update of the evidence

A growing body of evidence on diabetes screening has been published during the last 10 years. Type 2 diabetes meets many but not all of the criteria for screening. Concerns about potential harms of screening have largely been resolved. Screening identifies a high-risk population with the potential to gain from widely available interventions. However, in spite of the findings of modelling studies, the size of the benefit of earlier initiation of treatment and the overall cost-effectiveness remains uncertain, in contrast to other screening programmes (such as for abdominal aortic aneurysms) that are yet to be fully implemented. There is also uncertainty about optimal specifications and implementation of a screening programme, and further work to complete concerning development and delivery of individual- and population-level preventive strategies. While there is growing evidence of the net benefit of earlier detection of individuals with prevalent but undiagnosed diabetes, there remains limited justification for a policy of universal population-based screening for type 2 diabetes at the present time. Data from ongoing studies should inform the key assumptions in existing modelling studies and further reduce uncertainty.

Hospital admissions for asthma, diabetes and COPD: is there an association with practice nurse staffing? A cross sectional study using routinely collected data

BACKGROUND

Delivering good quality primary care for patients with chronic conditions has the potential to reduce non-elective hospital admissions. Practice nurse staffing levels in England have been linked to attainment of general practice performance targets for some chronic conditions. The aim of this study was to examine whether practice nurse staffing level is similarly associated with non-elective hospital admissions in three clinical areas: asthma, Chronic Obstructive Pulmonary Disease (COPD) and diabetes.

METHODS

This observational study used cross sectional analysis of routinely collected data. Hospital admissions data for the period 2005-2006 (for asthma, COPD and diabetes) were linked with a database of practice characteristics, nurse staffing data and data on population characteristics for the same period. Statistical modelling explored the relationship between non-elective hospital admission rates for the three conditions and the list size per full time equivalent (FTE) practice nurse.

RESULTS

Higher practice nurse staffing levels were significantly associated with lower rates of admission for asthma (p < 0.001) and COPD (p < 0.001). A similar association was seen for patients with two or more admissions (p < 0.05 for asthma and p < 0.001 for COPD). For diabetes, higher practice nurse staffing level was significantly associated with higher admission rates (p < 0.05), but this association was not significant in case of patients with two or more admissions. Across all models, increasing deprivation was associated with higher admission rates for all conditions.

CONCLUSIONS

The inconsistent relationship between nurse staffing and patient outcomes across the different conditions and the fact that for diabetes the relationship between staffing and outcomes was in a different direction from the association between staffing and care quality, highlights the need to avoid making a simple causal interpretation of these findings and reduces the possible confidence in such conclusions. There is a need for more research into the organisation and delivery of diabetes care services in general practice, preferably using patient level data; in order to better understand the impact of the different staffing configurations on patient outcomes.

Recent advances in the management of chronic stable angina II. Anti-ischemic therapy, options for refractory angina, risk factor reduction, and revascularization

The objectives in treating angina are relief of pain and prevention of disease progression through risk reduction. Mechanisms, indications, clinical forms, doses, and side effects of the traditional antianginal agents - nitrates, β-blockers, and calcium channel blockers - are reviewed. A number of patients have contraindications or remain unrelieved from anginal discomfort with these drugs. Among newer alternatives, ranolazine, recently approved in the United States, indirectly prevents the intracellular calcium overload involved in cardiac ischemia and is a welcome addition to available treatments. None, however, are disease-modifying agents. Two options for refractory angina, enhanced external counterpulsation and spinal cord stimulation (SCS), are presented in detail. They are both well-studied and are effective means of treating at least some patients with this perplexing form of angina. Traditional modifiable risk factors for coronary artery disease (CAD) - smoking, hypertension, dyslipidemia, diabetes, and obesity - account for most of the population-attributable risk. Individual therapy of high-risk patients differs from population-wide efforts to prevent risk factors from appearing or reducing their severity, in order to lower the national burden of disease. Current American College of Cardiology/American Heart Association guidelines to lower risk in patients with chronic angina are reviewed. The Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial showed that in patients with stable angina, optimal medical therapy alone and percutaneous coronary intervention (PCI) with medical therapy were equal in preventing myocardial infarction and death. The integration of COURAGE results into current practice is discussed. For patients who are unstable, with very high risk, with left main coronary artery lesions, in whom medical therapy fails, and in those with acute coronary syndromes, PCI is indicated. Asymptomatic patients with CAD and those with stable angina may defer intervention without additional risk to see if they will improve on optimum medical therapy. For many patients, coronary artery bypass surgery offers the best opportunity for relieving angina, reducing the need for additional revascularization procedures and improving survival. Optimal medical therapy, percutaneous coronary intervention, and surgery are not competing therapies, but are complementary and form a continuum, each filling an important evidence-based need in modern comprehensive management.

[Diagnosis and management of type 2 diabetes]

In 2010, the American Diabetes Association included glycosylated hemoglobin (HbA1c) as a criterion for the diagnosis of diabetes with a cut-off point of ≥ 6.5%. However, there may be a substantial percentage of false negative results. Other scientific societies have accepted this approach but with slight differences. HbA1c complements, but does not substitute, basal glycemia as a screening and diagnostic test or the 2-hour oral glucose tolerance test. HbA1c should not be used for the diagnosis of gestational diabetes. Interpretation of HbA1c is limited in persons with anemia and hemoglobinopathies. Therefore, in addition to its sensitivity and specificity, its costs and the epidemiological situation should also be evaluated. An important question is whether almost normal HbA1c levels are safe in patients with type 2 diabetes. The results of the ACCORD, ADVANCE and VADT trials are contradictory and have aroused considerable controversy. However, the extensions of the UKPDS and STENO-2 studies have shown the benefits of good glycemic control in the long term. As a general rule, a target of HbA1c < 7% seems appropriate. In patients at low risk of hypoglycemic episodes, short disease duration and young persons, HbA1c < 6.5% can be considered. In patients with frequent hypoglycemic episodes, the elderly and persons with short life expectancy, values of more than 7% are acceptable. This target should be achieved through individualized, early, intensive and safe treatment, without risk of hypoglycemia, and should be integrated in an overall program of cardiovascular risk prevention.

Intensive glucose control and cardiovascular outcomes in type 2 diabetes

Numerous observational studies have clearly shown a relationship between hyperglycaemia and cardiovascular (CV) disease. However, the United Kingdom Prospective Diabetes Study (UKPDS), which involved subjects with newly diagnosed type 2 diabetes, just failed to show that intensive glucose control significantly reduces CV events. The results of three subsequent large randomised controlled trials, the Action to Control Cardiovascular Risk in Diabetes (ACCORD), Action in Diabetes and Vascular Disease Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE) and the Veterans Administration Diabetes Trial (VADT), that involved approximately 25,000 subjects with established type 2 diabetes also failed to show that intensive glucose control, aiming for a glycated haemoglobin (HbA(1c)) level<7%, significantly reduces CV events. The ACCORD trial even suggested that under certain circumstances, intensive glucose control is associated with an increased risk for CV and all-cause mortality. Although the exact mechanisms responsible for an increase in mortality in the ACCORD trial remain unknown, there was an association between increased rates of mortality with higher rates of severe hypoglycaemia in the intensive glucose control group. In contrast, a 10-year post-randomisation follow-up study of the tight glucose intervention arm of the UKPDS showed that intensive glucose control was associated with a significant reduction in the risk for myocardial infarction (MI), diabetes-related deaths and all-cause mortality. This suggests that early strict glucose control generates a legacy effect that is eventually translated into protection from CV events. Recent meta-analyses of the above randomised trails have also shown that intensive glucose control is associated with a reduced risk of MI, without a clear benefit on other CV diseases such as stroke. Furthermore, these analyses have also shown that intensive glucose control is associated with increased rates of severe hypoglycaemia but not increased rates of CV or all-cause mortality. Aiming for HbA(1c) levels of <7.0% still remains the general target for good glucose control. Under certain circumstances, aiming for lower HbA(1c) levels may be appropriate. This applies in the setting of newly diagnosed diabetes in relatively young individuals without significant co-morbidities and in patients treated with agents that minimise the risk of severe hypoglycaemia such as metformin. Whether this also applies to newer glucose-lowering agents that target the incretin system will depend on CV outcomes of long-term studies which are in progress.

The case for hypoglycaemia as a proarrhythmic event: basic and clinical evidence

Recent clinical studies show that hypoglycaemia is associated with increased risk of death, especially in patients with coronary artery disease or acute myocardial infarction. This paper reviews data from cellular and clinical research supporting the hypothesis that acute hypoglycaemia increases the risk of malignant ventricular arrhythmias and death in patients with diabetes by generating the two classic abnormalities responsible for the proarrhythmic effect of medications, i.e. QT prolongation and Ca(2+) overload. Acute hypoglycaemia causes QT prolongation and the risk of ventricular tachycardia by directly suppressing K(+) currents activated during repolarisation, a proarrhythmic effect of many medications. Since diabetes itself, myocardial infarction, hypertrophy, autonomic neuropathy and congestive heart failure also cause QT prolongation, the arrhythmogenic effect of hypoglycaemia is likely to be greatest in patients with pre-existent cardiac disease and diabetes. Furthermore, the catecholamine surge during hypoglycaemia raises intracellular Ca(2+), thereby increasing the risk of ventricular tachycardia and fibrillation by the same mechanism as that activated by sympathomimetic inotropic agents and digoxin. Diabetes itself may sensitise myocardium to the arrhythmogenic effect of Ca(2+) overload. In humans, noradrenaline (norepinephrine) also lengthens action potential duration and causes further QT prolongation. Finally, both hypoglycaemia and the catecholamine response acutely lower serum K(+), which leads to QT prolongation and Ca(2+) loading. Thus, hypoglycaemia and the subsequent catecholamine surge provoke multiple, interactive, synergistic responses that are known to be proarrhythmic when associated with medications and other electrolyte abnormalities. Patients with diabetes and pre-existing cardiac disease may therefore have increased risk of ventricular tachycardia and fibrillation during hypoglycaemic episodes.

Estimation of primary care treatment costs and treatment efficacy for people with Type 1 and Type 2 diabetes in the United Kingdom from 1997 to 2007*

AIMS

The purpose of this study was to characterize the financial cost and efficacy of primary care treatment for diabetes in the United Kingdom from 1997 to 2007.

METHODS

Retrospective data were analysed for people with Type 1 and Type 2 diabetes along with matched control subjects using data from The Health Improvement Network. Costs were attributed from published sources and adjusted for price inflation. Type 2 diabetes was analysed by five commonly used treatment regimens.

RESULTS

It was possible to identify 126 052 people for inclusion: 11 300 (8.9%) with Type 1 diabetes and 114 752 (91.1%) with Type 2. The overall mean prescribing costs per person per year (pppy) increased markedly for people with diabetes from 1997 to 2007: for Type 1, from 573 pounds to 1014 pounds pppy (+77%), and for Type 2, from 39 pounds to 740 pounds pppy (+89%). In 2007, diabetes-treatment-specific prescribing represented 57% of prescribing costs in Type 1 diabetes and 28% in Type 2 diabetes. In Type 2 diabetes there was a mean of 5.4 primary care consultations in 1997, increasing to 11.5 pppy in 2007 (+112%). In 1997 the total mean cost of primary care treatment for Type 2 diabetes was 602 pounds pppy, increasing to 1080 pounds in 2007. In Type 1 diabetes, the mean glycated haemoglobin decreased by 0.1% from 8.8% in 2001 to 8.7% in 2007; the corresponding change using insulin in Type 2 diabetes was also 0.1%. Greater improvement in blood pressure and lipids was evident.

CONCLUSIONS

Over the 10 year period to 2007, diabetes-related primary care adjusted costs increased considerably, whereas glycated haemoglobin values did not improve at all over the same period.

Type 2 diabetes mellitus and the cardiometabolic syndrome: impact of incretin-based therapies

The rates of type 2 diabetes mellitus, obesity, and cardiovascular disease (CVD) continue to increase at epidemic proportions. It has become clear that these disease states are not independent but are frequently interrelated. By addressing conditions such as obesity, insulin resistance, stress hyperglycemia, impaired glucose tolerance, and diabetes mellitus, with its micro- and macrovascular complications, a specific treatment strategy can be developed. These conditions can be addressed by early identification of patients at high risk for type 2 diabetes, prompt and aggressive treatment of their hyperglycemia, recognition of the pleiotropic and synergistic benefits of certain antidiabetes agents on CVD, and thus, avoiding potential complications including hypoglycemia and weight gain. Incretin-based therapies, which include glucagon-like peptide-1 (GLP-1) receptor agonists and dipeptidyl peptidase-IV (DPP-IV) inhibitors, have the potential to alter the course of type 2 diabetes and associated CVD complications. Advantages of these therapies include glucose-dependent enhancement of insulin secretion, infrequent instances of hypoglycemia, weight loss with GLP-1 receptor agonists, weight maintenance with DPP-IV inhibitors, decreased blood pressure, improvements in dyslipidemia, and potential beneficial effects on CV function.

Dispensing patterns and financial costs of glucose-lowering therapies in the UK from 2000 to 2008

INTRODUCTION

A variety of influences determine prescribing behaviour. The purpose of this study was to characterize the pattern of dispensing for glucose-lowering and monitoring in the UK from 2000 to 2008, inclusively.

METHODS

Open source data were used from the four UK prescription pricing agencies. Historical patterns of dispensing change were analysed in England, thus data are for England unless otherwise stated. Costs were adjusted for price inflation and reported in UK pound at 2008 prices.

RESULTS

The total cost in the UK in 2008 was 702 239 000 UK pounds: 22 897 000 pounds (3.2%) for Northern Ireland, 37 681 000 pounds (5.3%) for Wales, 57 146 000 pounds (8.1%) for Scotland and 590 514 000 pounds (83.4%) for England. As a per cent of the overall primary care drug budget for each region, this represented 6.9% overall and then 5.8, 6.5, 5.9 and 7.1%, respectively. In England, diabetes-related dispensing costs increased from 290m to 591m UK pounds. All glucose-lowering drug classes increased in volume, except the alpha-glucoside inhibitors and the prandial glucose regulators. Insulin costs increased from 128m to 286m UK pounds. Insulin glargine metrics increased year-on-year, whereas neutral protamine Hagedorn (NPH) declined. Analogue insulin increased (2.6 million to 33.9 million prescription items), whereas human insulin declined (21.0 million to 10.3 million).

DISCUSSION

The costs of dispensing for diabetes increased markedly between 2000 and 2008 to represent an annual cost to the NHS of 708m UK pounds, or 7% of budget. Costs increased at a higher rate than volume. Changes in prescribing appeared to reflect commercial factors more than clinical evidence. Diabetes dispensing patterns need to be better controlled and costs contained.

Liraglutide, the once-daily human GLP-1 analog, in the treatment of Type 2 diabetes

Type 2 diabetes is a progressive disorder characterized by continuous deterioration in β-cell function requiring an escalation of therapeutic efforts in order to maintain glycemic control. Recent studies have demonstrated that the current antidiabetic treatments, including metformin, sulfonylureas and thiazolidinediones, are not durable, resulting in an increase of hemoglobin A_1c over time with all three therapies. Many current antidiabetic treatments (sulfonylureas, thiazolidinediones and insulin) are associated with the undesirable feature of weight gain. In addition, sulfonylureas and insulin are associated with an increased risk for hypoglycemia. The unsatisfactory results with the current pharmacological therapies for Type 2 diabetes have encouraged the development of a number of novel treatments. Among these are the incretin-based therapies, which include glucagon-like peptide (GLP)-1 receptor agonists; this article focuses on one of these agonists, the human GLP-1 analog liraglutide. Liraglutide has been approved for use in Type 2 diabetic individuals in several countries, including Europe, the USA and Japan.

Obesity and diabetes: the links and common approaches

The term "diabesity" was famously coined by Sims and colleagues in the 1970s, to highlight the close relationship between type 2 diabetes and obesity. His team demonstrated that young men with no family history of diabetes when overfed for 6 months underwent a BMI increase to 28.0kg/m(2) alongside reversible rises in levels of fasting insulin, glucose, and triglycerides, and impaired glucose tolerance. Around 90% of type 2 diabetic patients have a BMI greater than 23.0kg/m(2), the risk of diabetes being greatly increased by a family history of diabetes or gestational diabetes, and early weight gain, especially in childhood. Patients with T2DM with co-existing obesity, can potentially be offered sub-optimum treatment at various points in the progression of their illness, unless the Primary healthcare team simultaneously embraces state-of-the-art methods within the fields of both diabetes and obesity. Obese individuals may be victims of inadequate screening, denying the chance of crucial early treatment, they may be left to languish at suboptimal HbA1c, they may be prescribed drugs which induce weight gain, whilst already being obese, vulnerable individuals may be given drugs which induce hypoglycaemia - often guideline and QOF led - and ultimately they may be converted to insulin before preferable alternatives have been explored. There have been many recent advances in both the fields of diabetes and obesity and it is important for clinicians to be aware of and familiar with newer interventions in both areas, as best practice and best outcomes are not achieved in their absence.

Is the ADA/EASD algorithm for the management of type 2 diabetes (January 2009) based on evidence or opinion? A critical analysis

The ADA and the EASD recently published a consensus statement for the medical management of hyperglycaemia in patients with type 2 diabetes. The authors advocate initial treatment with metformin monotherapy and lifestyle modification, followed by addition of basal insulin or a sulfonylurea if glycaemic goals are not met (tier 1 recommendations). All other glucose-lowering therapies are relegated to a secondary (tier 2) status and only recommended for selected clinical settings. In our view, this algorithm does not offer physicians and patients the appropriate selection of options to individualise and optimise care with a view to sustained control of blood glucose and reduction both of diabetes complications and cardiovascular risk. This paper critically assesses the basis of the ADA/EASD algorithm and the resulting tiers of treatment options.

Critical appraisal of the safety and efficacy of insulin detemir in glycemic control and cardiovascular risk management in diabetics

Insulin detemir is an analog of human insulin designed to provide a long duration of basal insulin action. This is achieved by protracted absorption from the injection depot, which results in part from increased self-association of insulin detemir molecules and in part from reversible albumin binding. Subsequent albumin binding in the circulation is thought to buffer changes in the effects at target tissues that could otherwise arise from variability in absorption rate. In consequence, insulin detemir has shown a less variable pharmacodynamic profile than alternative basal insulins; this manifests as more consistent temporal glucose reduction profiles in repeat-clamp studies. In clinical trials, insulin detemir has been characterized by consistent risk reductions in hypoglycemia, as well as reduced weight gain in comparison with other basal insulins. Given some recent associations that have been made in prospective and epidemiologic studies between glucose variability and/or hypoglycemia and increased cardiovascular risk, and the long-known association between excess weight and cardiovascular risk, it is possible that the clinical profile of insulin detemir may carry prognostic value with regard to cardiovascular safety, although this is yet to be substantiated. There have also been some concerns raised recently over the use of insulin analogs and cancer risk, but available clinical data and the receptor interaction profile of insulin detemir suggest no excess in risk in comparison with human insulin therapy. Optimal approaches for the clinical use of insulin detemir have been emerging through an increasing clinical study base, and the analog is becoming established as a potentially valuable therapy option.

Surgical interventions to correct metabolic disorders

Obesity and related metabolic disorders are increasing especially in developing countries. It is widely accepted that in extremely obese patients bariatric surgery reduces body weight and improves type 2 diabetes and the metabolic syndrome. Weight loss partially explains this effect as do weight loss-independent mechanisms linked to gut hormones, peptide YY, ghrelin, glucagon-like peptide-1, and glucose-dependent insulinotropic peptide/gastric inhibitory polypeptide. Several groups performing established and novel surgical techniques have shown encouraging metabolic results. Herein we consider whether it is theoretically plausible to use surgery as an alternative or complementary approach to medical treatment of diabetes in overweight and mildly obese patients.

Engaging and empowering patients to manage their type 2 diabetes, Part I: a knowledge, attitude, and practice gap?

For over 20 years, the World Health Assembly has recognized diabetes (type 1 and type 2) as a serious threat to national health and economic development and called for action regarding its prevention and control. However, the prevalence of type 2 diabetes continues to rise despite a significant percentage of cases being preventable. Furthermore, data suggest that in many patients diagnosed with type 2 diabetes, glycated hemoglobin (HbA(1c)) levels remain above the agreed international and national target levels, despite the availability of numerous antihyperglycemic agents, the best intentions of both patient and physician, and the support of the wider healthcare team. Part I of this two-part review considers evidence that seems to suggest there is a knowledge, attitude, and practice (KAP) gap in type 2 diabetes, and that although theoretical knowledge of how type 2 diabetes should be managed exists, the attitude of patients and healthcare professionals may influence the practicalities of implementing life-enhancing changes for patients living day-to-day with the condition. Here, we consider why there may be a KAP gap, how type 2 diabetes is currently being assessed and managed, and whether these current management approaches remain valid in the light of recent studies evaluating the impact of lowering current target HbA(1c) levels. This article also explores how encouraging patients to self-manage their disease, as well as engaging all stakeholders in the necessary behavioral changes, can positively influence the long-term treatment outcomes of patients with type 2 diabetes.

Mistakes, misunderstandings and controversies in diabetes: A review and personal account

A number of controversies in diabetes have had too little attention. I discuss the following issues: (i) drug therapy; (ii) genetics; (iii) antihypertensive treatment in patients with normoalbuminuria and with abnormal albuminuria; (iv) insulin analogs; (v) cancer in diabetes; (vi) hypophysectomy; (vii) renal biopsy; (viii) low protein diet; and (ix) glycated hemoglobin. A closer look at these items is required in order to have a more realistic picture of diabetes research. A scheme of other controversies is also provided. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2010.00012.x, 2010)