Current Diabetes Reviews - Volume 7, Issue 3, 2011

The aim of the present review is to synthesis findings from studies on the relationship between socioeconomic position (SEP) and incidence, prevalence and mortality of type 2 diabetes mellitus (T2DM) in Europe between the years 1999 and 2009. A systematic search was carried out in the National Library of Medicine's PubMed database. The search was limited to articles published between January 1999 and December 2009, in English or Spanish. Additional requirements for inclusion were: (i) presentation of empirical results directly related with SEP and the prevalence, incidence or mortality of diabetes, (ii) dealing with T2DM, (iii) carried out in Europe, and (iv) mainly focused only on diabetes. Of the 19 articles found, twelve studied the relationship between SEP and the prevalence of T2DM, two dealt with diabetes incidence, three with mortality and two studied both inequalities in mortality and prevalence. People with more deprived SEP have greater incidence, more prevalence and higher mortality due to T2DM, although the magnitude and significance of the associations varied from one study to another. Part of these inequalities is explained by SEP differences in the prevalence of the established T2DM risk factors. SEP inequalities in T2DM tended to be greater in women than in men. There is consistent evidence that SEP inequalities in T2DM incidence, prevalence and mortality are present in Europe, especially among women. Improving accessibility of physical activity in terms of both price and availability, access to healthy food, and access to health services, will be key to achieving a reduction of SEP related diabetes inequalities in Europe.

High plantar pressures lead to ulceration in the diabetic foot, particularly in the forefoot region around the metatarsal heads. High plantar pressures persist during gait due to factors such as peripheral neuropathy, foot deformities, limited ankle dorsi flexion range of motion and reduced plantar tissue thickness. Strategies impinging upon gait such as the use of appropriate therapeutic footwear, custom-moulded insoles and injectable silicone can help to reduce plantar pressures and attenuate the risk for ulceration. Shoes adapted with external rocker profiles facilitate plantar flexion and restrict sagittal plane motion of the metatarsophalangeal joint, reducing pressures in the region of the metatarsal heads. Insoles custom-moulded to patient's feet help to reduce plantar pressures and minimise the risk of ulceration in the forefoot region. The loss of subcutaneous fat tissue in the diabetic foot enhances bony prominences and predisposes the foot to high-pressure areas. Silicone is a biocompatible material that can be safely injected into plantar soft tissue to augment tissue thickness and prevent the development of ulceration. This enhancement to the subcutaneous layer is remarkably well retained and is a generally well-adopted procedure in the clinical setting.

Childhood obesity is a significant, worldwide, public health problem. Coinciding with the increasing prevalence of obesity in youth, Type 2 diabetes has emerged as a critical health condition in this population. In the U.S. alone, approximately 215,000 U.S. youth under the age of 20 were diagnosed with diabetes, with the majority of 10-19 years old diagnosed with Type 2 diabetes. Additionally, the exact number of youth that may have Type 2 diabetes yet remain undiagnosed is unknown. Increasing physical activity to encourage weight loss among youth may reduce the incidence of Type 2 diabetes in youth; however, several recent studies reported positive associations between physical activity and components of Type 2 diabetes without weight loss in youth. These findings support previous studies in adults which observed physical activity-induced improvements in insulin dynamics without changes in body fat. The purpose of this review was to identify studies which examined the effect of physical activity without dietary intervention on markers of insulin resistance in overweight and obese youth. These studies provide strong evidence that physical activity alone, without dietary intervention, can have a positive, significant impact on insulin resistance risk and potentially prevent the development of type 2 diabetes in overweight and obese youth. The studies reviewed provide support for future interventions to shift the focus from reducing obesity to increasing physical activity for the prevention of type 2 diabetes in obese youth.

Diabetes mellitus is a growing global epidemic. Patients with this disease present with a variety of health conditions, including a number of ocular complications that threaten vision, such as proliferative diabetic retinopathy and macular edema. Diabetic papillopathy, another potential ocular complication from diabetes, is a self-limiting, sometimes bilateral disease that may affect both type 1 and type 2 diabetics. It is characterized by optic disc swelling caused by vascular leakage and axonal edema in and around the optic nerve head. Occasionally, it may be accompanied by intraretinal hemorrhages and hard exudates. Diabetic papillopathy tends to be mild and is usually associated with good visual prognosis; however, there are some cases in which permanent visual impairment can develop. The pathogenesis remains largely unknown, but there has been evidence suggestive of its associations with a small cup/disc ratio and rapid reduction in glycemia. There is no validated therapy for diabetic papillopathy; however, current case reports have shown promising results after local injections of corticosteroids as well as bevacizumab (Avastin), a potent monoclonal antibody that has been employed for the treatment of ocular vaso-proliferative diseases such as choroidal neovascular membranes associated with age-related macular degeneration and proliferative diabetic retinopathy.

The use of intravitreal anti vascular endothelial growth factor (anti-VEGF) drugs such as pegaptanib, ranibizumab and bevacizumab has been widely reported to treat complications such as macular edema and rubeosis. During the past few years they have also been used as an adjuvant therapy to reduce intraocular bleeding during vitrectomy in eyes with proliferative diabetic retinopathy as well as to reduce the occurrence of vitreous haemorrhages in vitrectomized eyes and facilitate glaucoma surgery. In this paper we review the use of anti VEGF drugs in the surgical management of diabetic retinopathy related complications.

Over 220 million individuals have type-2 diabetes mellitus (T2DM) worldwide. Obesity has been identified as a significant risk factor for the development of T2DM. Overweight or obese individuals develop insulin resistance with resultant hyperinsulinemia. This process may progress to impaired glucose intolerance and eventual T2DM. There is strong evidence indicating that bariatric surgery may produce sustainable long-term weight loss in obese individuals. Bariatric surgery consists of surgical operations classified as either primarily restrictive or malabsorptive. Restrictive bariatric procedures include gastric banding or sleeve gastrectomy, while malabsorptive procedures included gastric bypass and biliopancreatic diversion. Malabsorptive procedures have been shown to be superior in producing dramatic weight loss along with resolution or improvement of T2DM. Interestingly, improvement of diabetes has been shown to occur shortly following malabsorptive bariatric surgery, prior to significant weight loss, suggesting that hormone-mediated mechanisms may be involved. As the prevalence of obesity and T2DM continues to rise, so may the role of bariatric surgery to combat this growing epidemic.

Diabetic retinopathy is the most common microvascular complication of diabetes mellitus and is the leading cause of blindness amongst working-age adults in Western countries. Large observational and randomized studies have consistently shown that optimal blood glucose and blood pressure control is the key component of intervention strategies aimed to halt or regress the disease, and limit the risk of progression to the proliferative stage, with consequent visual loss up to blindness in most severe cases. Amelioration of dyslipidemia by statins, especially if combined with fenofibrate, may also ameliorate retinopathy in line with a potential pathogenic role of hyperlipidemia. Recently, evidence has also emerged that renin-angiotensin system (RAS) inhibitors may electively prevent or delay progression of retinopathy, possibly because of specific protective effect against the structural and functional retinal changes sustained by local RAS activation. Thus, metabolic and blood pressure control by RAS inhibition is to prevent or limit the onset of retinopathy and its progression towards visual-threatening stages. Topic treatment with anti-vascular endothelial growth factor (VEGF) agents is emerging as a treatment option for retinopathy in advanced stages to limit the need for laser photocoagulation. This option however should be considered with caution due to the risk of systemic adverse events.

Recent evidence highlights an important role of ghrelin in glucose homeostasis. In this review we provide a detailed summary of recent advances in this field. We describe the effects of ghrelin on all aspects of glucose homeostasis including glucose-stimulated insulin secretion, hepatic glucose production and insulin stimulated glucose disposal in the peripheral tissues. The existing evidence suggests ghrelin primarily inhibits insulin release from the pancreas and we highlight an important mechanism involving AMPK-UCP2 ATP-stimulated potassium channels and intracellular calcium regulation. Ghrelin increases hepatic glucose production and prevents glucose disposal in muscle and adipose tissues, which collectively leads to hyperglycemia and impaired glucose tolerance. We discuss the important role ghrelin plays in glucose homeostasis during different metabolic states. During severe calorie restriction, ghrelin increases blood glucose concentrations in order to maintain glucose homeostasis. In diet-induced obesity, ghrelin exacerbates hyperglycemia and promotes a diabetic phenotype.

Approximately one in three people with diabetes is affected by diabetic distal symmetric sensorimotor polyneuropathy (DSPN), which represents a major health problem as it may present with excruciating neuropathic pain and is responsible for substantial morbidity, increased mortality and impaired quality of life. Neuropathic pain causes considerable interference with sleep, daily activities, and enjoyment of life. Treatment is based on four cornerstones: (1) intensive diabetes therapy and multifactorial risk intervention; (2) treatment based on pathogenetic mechanisms; (3) symptomatic treatment; and (4) avoidance of risk factors and complications. Recent experimental studies suggest a multifactorial pathogenesis of diabetic neuropathy. From the clinical point of view, it is important to note that, based on these pathogenetic mechanisms, therapeutic approaches could be derived, some of which are currently being evaluated in clinical trials. Management of chronic painful DSPN remains a challenge for the physician and should consider the following practical rules: the appropriate and effective drug has to be tried and identified in each patient by carefully titrating the dosage based on efficacy and side effects; lack of efficacy should be judged only after 2-4 weeks of treatment using an adequate dosage. Analgesic combination therapy may be useful, and potential drug interactions have to be considered given the frequent polypharmacy in people with diabetes. Not only increased alcohol consumption but also the traditional cardiovascular risk factors such as visceral obesity, hypertension, hyperlipidemia and smoking have a role in the development and progression of diabetic neuropathy and hence need to be prevented or treated.