Prevention of Type 2 diabetes mellitus. A review of the evidence and its application in a UK setting

Intervention fidelity assessment: A sub-study of the Norfolk Diabetes Prevention Study (NDPS)

BACKGROUND

Previous research has shown that lifestyle modification can delay or prevent the onset of type 2 diabetes in high-risk individuals. The Norfolk Diabetes Prevention Study (NDPS) was a parallel, three-arm, randomized controlled trial with up to 46 months follow-up that tested a group-delivered, theory-based lifestyle intervention to reduce the incidence of type 2 diabetes in high-risk groups. The current study aimed to evaluate if the NDPS intervention was delivered to an acceptable standard and if any part(s) of the delivery required improvement.

METHODS

A sub-sample of 30, 25 for inter-rater reliability and audio-recordings of the NDPS intervention education sessions were assessed independently by two reviewers (CT, TW) using a 12-item checklist. Each item was scored on a 0-5 scale, with a score of 3 being defined as 'adequate delivery'. Inter-rater reliability was assessed. Analysis of covariance (ANCOVA) was used to assess changes in intervention fidelity as the facilitators gained experience.

RESULTS

Inter-rater agreement was acceptable (86%). A mean score of 3.47 (SD = .38) was achieved across all items of the fidelity checklist and across all intervention facilitators (n = 6). There was an apparent trend for intervention fidelity scores to decrease with experience; however, this trend was non-significant (p > .05) across all domains in this small sample.

CONCLUSION

The NDPS was delivered to an acceptable standard by all Diabetes Prevention Facilitators. Further research is needed to better understand how the intervention's delivery characteristics can be optimized and how they might vary over time.

Effects of aerobic training and vitamin D supplementation on glycemic indices and adipose tissue gene expression in type 2 diabetic rats

Type 2 diabetes mellitus (T2DM) is a progressive metabolic disorder mainly caused by overweight and obesity that accumulates pro-inflammatory factors in adipose tissue. Studies have confirmed the efficacy of exercise and vitamin D supplementation in preventing, controlling, and treating diabetes. While, reduced physical activity and vitamin D deficiency are related to increased adiposity, blood glucose level, insulin concentration, and insulin resistance. This study purposed to investigate the effect of 8-week aerobic training with vitamin D supplementation on the expression of AMPK, PGC-1α, and UCP-1 genes expression in the visceral adipose tissue of obese rats with T2DM. In this experimental study, fifty male Wistar rats were divided into 5 groups (n = 10): aerobic training and vitamin D supplementation (AT + Vit D), aerobic training (5 days/week for 8 weeks; AT), vitamin D supplementation (Vit D), diabetic control (C) and NC (Non-Diabetic Control). AT + Vit D and AT groups practiced an 8-week aerobic training, 5 days a week. Vit D and AT + Vit D groups receive 5000 IU of vitamin D by injection once a week while AT and C received sesame oil. After blood sampling, visceral fat was taken to measure AMPK, PGC-1α, and UCP1 gene expression. Data were statistically analyzed by One-way ANOVA and paired sample t-test at a significance level of p < 0.05. Based on our results BW, BMI, WC, visceral fat, insulin, glucose, and HOMA-IR were significantly lower in the AT + Vit D, AT, and Vit D groups compared with the C group (p < 0.01). Furthermore, AT + Vit D, AT, and Vit D upregulated AMPK, PGC-1α, and UCP1 gene expression compared to the C. Based on the results compared to AT and Vit D, AT + Vit D significantly upregulated AMPK (p = 0.004; p = 0.001), PGC-1α (p = 0.010; p = 0.001), and UCP1 (p = 0.032; p = 0.001) gene expression, respectively. Also, AT induced more significant upregulations in the AMPK (p = 0.001), PGC-1α (p = 0.001), and UCP1 gene expression (p = 0.001) than Vit D. Vitamin D supplementation enhanced the beneficial effects of aerobic training on BW, BMI, WC, visceral fat, insulin, glucose, and HOMA-IR in diabetic rats. We also observed that separate AT or Vit D upregulated the gene expression of AMPK, PGC-1α, and UCP1 however, combined AT + Vit D upregulated AMPK, PGC-1α, and UCP1 more significantly. These results suggested that combining aerobic training and vitamin D supplementation exerted incremental effects on the gene expressions related to adipose tissue in animal models of diabetes.

Ferula assa-foetida oleo gum resin ethanolic extract alleviated the pancreatic changes and antioxidant status in streptozotocin-induced diabetic rats: A biochemical, histopathological, and ultrastructural study

The current research examines the effects of administration of 150 and 250 mg/kg body weight/day of ethanolic Ferula assa-foetida L. oleo gum resin extract (FAE) for 42 days in streptozotocin-induced diabetes in rats. On day 42, all rats were euthanized; HOMA-β, HOMA-IR, and QUICKI levels in pancreas were examined histopathologically and ultrastructurally . Low-dose FAE (150 mg/kg) treatment resulted in significant improvement in serum glucose, insulin and superoxide dismutase, glutathione, and catalase levels (p < .05). It also improved β-cell function, restored pancreatic β-cells, and reduced insulin resistance compared to the diabetic control rats. Necrotic and degenerative alterations in the islets, pyknotic β-cell nuclei, β-cell degranulation, reduced islet cellular density, and significant vacuolation were found in the islets of STZ-diabetic control group ratsby the histomorphological and ultrastructural examination. The pancreatic histomorphology of low dose of FAE-treated diabetic rats showed remarkable improvements in the islets, such as the β-cell number and the area of the pancreatic islets. PRACTICAL APPLICATIONS: The experiment revealed that Ferula assa-foetida L. may exert antihyperglycemic activity in STZ diabetes via β-cell regeneration and its high antioxidant capacity. This work elucidates the role of Ferula assa-foetida L. in diabetes management. Ferula assa-foetida L. gum extract improved the morphological changes of the diabetic pancreas and stimulated the regeneration of the β cells. The findings demonstrated positive results for the long-term cure of diabetes. Additionally, this study showed the potential of isolating nutraceuticals for the development of medications.

Acute and long-term effects of saxagliptin on post-prandial glycemic response in obese patients with impaired glucose tolerance

BACKGROUND AND AIMS

Dipeptidyl-peptidase inhibitors might be useful in type 2 diabetes prevention. ACCES (ACute and Chronic Effects of Saxagliptin) was a randomized, placebo-controlled, double-blind, controlled phase 2, pilot study aiming to examine in obese patients with impaired glucose tolerance (IGT) the acute effects and the effects after 12 weeks of treatment by saxagliptin on glucose levels at fasting and postprandially after a standard breakfast, and on glucose tolerance.

METHODS AND RESULTS

We included 24 obese patients with IGT. Patients were randomized to receive saxagliptin 5 mg or placebo in the morning. The treatment was taken on Visit 1 before breakfast, then continued for 12 weeks. Biochemical measurements were performed before, one, two and three hours after a standard breakfast including 75 g of carbohydrates, during Visit 1 and Visit 2 (12 weeks). Glucose variability (GV) was evaluated at Visit 1 from 24-h continuous glucose monitoring including the breakfast. A second OGTT was performed at Visit 3 (3-5 days after Visit 2). Compared with placebo-treated patients, saxagliptin-treated patients had lower 1 h and 2 h post-meal plasma glucose levels at Visit 1 and similar changes at Visit 2 (p < 0.01 to p < 0.004), with lower GV indexes after breakfast at Visit 1. At Visit 3, all patients but one in saxagliptin group and only 4 patients in placebo group turned to normal glucose tolerance. Lower glucose response to breakfast at Visit 1 was predictive of recovery of glucose tolerance.

CONCLUSION

Saxagliptin has metabolically beneficial effects in glucose-intolerant obese patients by significantly lowering postprandial blood glucose levels.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01521312: https://clinicaltrials.gov/ct2/show/NCT01521312.

In vitro and in vivo Antidiabetic Properties of Phenolic Antioxidants From Sedum adenotrichum

Natural products serve as the mainstay of human life, and today, almost half of the drugs in clinical practice are the natural origin. Keeping in view the importance of medicinal plants and natural products, Sedum adenotrichum also known as Rosularia adenotrichum was selected for the present study. The crude extract of S. adenotrichum whole plant was obtained through a rotary evaporator. The extract was analyzed for a polyphenolic profile using high-performance liquid chromatography with a diode-array detector. The extract was subjected to detail in vivo antidiabetic study. In this study, body weight, blood glucose level, glycated hemoglobin, lipid profile, liver function tests, and renal function tests were performed in animal models. The extract was tested for in vitro α-glucosidase inhibition activity. Results of high-performance liquid chromatography with a diode-array detector chromatogram revealed a total of 22 polyphenolic compounds. No major change in body weight was noted in experimental animals. Alloxan induction led to a significant elevation in plasma glucose level. A significant decline was noted in blood glucose and glycated hemoglobin concentration in rats treated with the extract as well as with glibenclamide. Renal/liver function tests, lipid profile, alkaline phosphatase, and serum cholesterol were normalized by the extract-treated rats. The α-glucosidase inhibitory activity at 62.5 and 1,000 μg/ml was noted to be 63.97 and 80.80, respectively, both approaching to standard. The results reveal that the extract was rich in important phenolic compounds. In the antidiabetic potentials of the crude extract, there might be involved several pancreatic and extra-pancreatic mechanisms acting synergistically to induce the potent antidiabetic effect.

Perceived barriers and facilitators of the implementation of a combined lifestyle intervention with a financial incentive for chronically ill patients

BACKGROUND

This study aims to describe barriers and facilitators of the implementation of a combined lifestyle intervention (CLI) in primary care for patients with chronic disease. The aim of CLI to help patients to create a healthy lifestyle and to maintain this healthy lifestyle. During a CLI a patient receives advice and counselling to improve health-related behavior such as physical activity and diet. Special attention was given to the influence of adding a health promoting financial incentive (HPFI) for the participants to the CLI.

METHODS

Twenty-four semi-structured interviews within six care groups were performed between July and October 2017. The interviews were transcribed verbatim and coded by two researchers independently.

RESULTS

Respondents mentioned several preferred characteristics of the CLI such as easy accessibility of the intervention site and the presence of health care professionals during exercise sessions. Moreover, factors that could influence implementation (such as attitude of the health care professionals) and preconditions for a successful implementation of a CLI (such as structural funding and good infrastructure) were identified. Overall, positive HPFIs (e.g. a reward) were preferred over negative HPFIs (e.g. a fine). According to the respondents, HPFIs could positively influence the degree of participation, and break down barriers for participating in and finishing the CLI.

CONCLUSIONS

Multiple barriers and facilitators for successful implementation of a CLI were identified. For successful implementing CLIs, a positive attitude of all stakeholders is essential and specific preconditions should be fulfilled. With regard to adding a HPFI, more research is needed to identify the attitude of specific target groups towards an HPFI.

Efficacy of Ginger (Zingiber officinale) in Ameliorating Streptozotocin-Induced Diabetic Liver Injury in Rats: Histological and Biochemical Studies

Ginger (Zingiber officinale) was reported to have an antioxidant, antidiabetic effect. This study was done to investigate its therapeutic effect against functional and structural alteration in liver of diabetic rat (intraperitoneal streptozotocin (STZ) in a dose of 60 mg/kg/bw). Thirty adult male rats (three-months-old and 250 g weight) were sorted into five groups (N=6). G1 used as control, G2 was diabetic rats without any treatment, G3 was diabetic rats given oral ginger in a dose of 500 mg/kg/bw, G4 was diabetic rats treated with metformin (500 mg/kg/bw) while G5 received ginger orally. The experiment lasts for six weeks, animals were anesthetized by ether, body weight was recorded for all animals. Blood was collected for further analysis of lipid profile, liver enzymes and total antioxidant. Liver was dissected, weighted and samples were processed for histopathological study. The results showed significant decrease of glaucous level and liver enzymes in ginger treated rats. Total antioxidant was preserved. Ginger lowered blood glucose, level, regained body weight and liver index to near normal values. Diabetes induced degenerative changes and micro-vesicular lipid deposition in hepatocytes with moderate portal area fibrosis. Ultrastructure study confirmed such changes beside demonstrating increased lipid deposition in fat storing cells. Ginger was found to ameliorate those changes in treated animals. Results were matching metformin effects. In conclusion, Ginger as a natural safe Herbal medication can be used to support liver functions in diabetic status.

Prevalence of gestational diabetes mellitus in Europe: A meta-analysis

AIMS

Estimates of the prevalence of gestational diabetes vary widely. It is important to have a clear understanding of the prevalence of this condition to be able to plan interventions and health care provision. This paper describes a meta-analysis of primary research data reporting the prevalence of gestational diabetes mellitus in the general pregnant population of developed countries in Europe.

METHODS

Four electronic databases were systematically searched in May 2016. English language articles reporting gestational diabetes mellitus prevalence using universal screening in general pregnant population samples from developed countries in Europe were included. All papers identified by the search were screened by one author, and then half screened independently by a second author and half by a third author. Data were extracted by one author. Values for the measures of interest were combined using a random effects model and analysis of the effects of moderator variables was carried out.

RESULTS

A total of 3258 abstracts were screened, with 40 studies included in the review. Overall prevalence of gestational diabetes mellitus was 5.4% (3.8-7.8). Maternal age, year of data collection, country, area of Europe, week of gestation at testing, and diagnostic criteria were found to have a significant univariate effect on GDM prevalence, and area, week of gestation at testing and year of data collection remained statistically significant in multivariate analysis. Quality category was significant in multivariate but not univariate analysis.

CONCLUSIONS

This meta-analysis shows prevalence of GDM that is at the upper end of previous estimates in Europe.

A community-based primary prevention programme for type 2 diabetes mellitus integrating identification and lifestyle intervention for prevention: a cluster randomised controlled trial

Background

Prevention of type 2 diabetes mellitus (T2DM) is a global priority; however, there is a lack of evidence investigating how to effectively translate prevention research into a primary care setting.

Objectives

(1) To develop and validate a risk score to identify individuals at high risk of T2DM in the UK; and (2) to establish whether or not a structured education programme targeting lifestyle and behaviour change was clinically effective and cost-effective at preventing progression to T2DM in people with prediabetes mellitus (PDM), identified through a risk score screening programme in primary care.

Design

A targeted screening study followed by a cluster randomised controlled trial (RCT), with randomisation at practice level. Participants were followed up for 3 years.

Setting

A total of 44 general practices across Leicestershire, UK. The intervention took place in the community.

Participants

A total of 17,972 individuals from 44 practices identified through the risk score as being at high risk of T2DM were invited for screening; of these, 3449 (19.2%) individuals attended. All received an oral glucose tolerance test. PDM was detected in 880 (25.5%) of those screened. Those with PDM were included in the trial; of these, 36% were female, the average age was 64 years and 16% were from an ethnic minority group.

Intervention

Practices were randomised to receive either standard care or the intervention. The intervention consisted of a 6-hour group structured education programme, with an annual refresher and regular telephone contact.

Main outcome measures

The primary outcome was progression to T2DM. The main secondary outcomes were changes in glycated haemoglobin concentrations, blood glucose levels, cardiovascular risk, the presence of metabolic syndrome, step count and the cost-effectiveness of the intervention.

Results

A total of 22.6% of the intervention group did not attend the education and 29.1% attended all sessions. A total of 131 participants developed T2DM (standard care,n = 67; intervention,n = 64). There was a 26% reduced risk of T2DM in the intervention arm compared with standard care, but this did not reach statistical significance (hazard ratio 0.74, 95% confidence interval 0.48 to 1.14;p = 0.18). There were statistically significant improvements in glycated haemoglobin concentrations, low-density lipoprotein cholesterol levels, psychosocial well-being, sedentary time and step count in the intervention group. The intervention was found to result in a net gain of 0.046 quality-adjusted life-years over 3 years at a cost of £168 per patient, with an incremental cost-effectiveness ratio of £3643 and a probability of 0.86 of being cost-effective at a willingness-to-pay threshold of £20,000.

Conclusions

We developed and validated a risk score for detecting those at high risk of undiagnosed PDM/T2DM. We screened > 3400 people using a two-stage screening programme. The RCT showed that a relatively low-resource pragmatic programme may lead to a reduction in T2DM and improved biomedical and psychosocial outcomes, and is cost-effective.

Limitations

Only 19% of those invited to screening attended, which may limit generalisability. The variation in cluster size in the RCT may have limited the power of the study.

Future work

Future work should focus on increasing attendance to both screening and prevention programmes and offering the programme in different modalities, such as web-based modalities. A longer-term follow-up of the RCT participants would be valuable.

Trial registration

Current Controlled Trials ISRCTN80605705.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme.

Alogliptin for the treatment of type 2 diabetes: a drug safety evaluation

INTRODUCTION

Dipeptidyl peptidase-4 (DPP-4) inhibitors such as alogliptin are becoming more widely established as treatment options for patients with type 2 diabetes (T2DM) because of their ability to improve glycemic control without increasing the risk of hypoglycemia or weight gain. New therapies with improved safety profiles are needed, especially because of the chronic and progressive nature of T2DM.

AREAS COVERED

In this article, the overall safety and tolerability of alogliptin are evaluated based upon a review of the literature. In particular, adverse events (AEs) that have been of interest for the DPP-4 class of drugs, such as the risk of major cardiovascular (CV) events and acute pancreatitis, will be investigated in detail.

EXPERT OPINION

Alogliptin is generally well-tolerated in a broad range of patient populations including different ethnic groups and the elderly. In the pivotal EXAMINE clinical trial, alogliptin was found not to be associated with an increased risk of major CV events or acute pancreatitis/pancreatic cancer.

Effect of Sitagliptin and Metformin on Prediabetes Progression to Type 2 Diabetes - A Randomized, Double-Blind, Double-Arm, Multicenter Clinical Trial: Protocol for the Sitagliptin and Metformin in PreDiabetes (SiMePreD) Study

Background

The high prevalence and incidence of type 2 diabetes mellitus (DM), and its associated morbidity and mortality, has prompted growing international interest and effort in the primary prevention of this disease. Primary prevention is possible since type 2 DM is preceded by prediabetes, offering a window opportunity to treat patients, and prevent the emergence of advanced disease. Sitagliptin is an oral dipeptidyl peptidase-IV inhibitor that preserves existing beta cell function and increases beta cell mass. These two effects have been demonstrated both in vitro and in animal studies, and current clinical data show that sitagliptin is safe. Metformin, a biguanide, reduces insulin resistance and inhibits hepatic gluconeogenesis, and has an excellent safety profile. The combination of metformin and sitagliptin, targeting both characteristics of prediabetes (insulin resistance and progressive beta cell degeneration), may potentially slow or halt the progression from prediabetes to type 2 DM. This paper describes the rationale and design of the Sitagliptin and Metformin in PreDiabetes (SiMePreD) study.

Objective

The aim of this study is to determine the effect of sitagliptin and metformin on progression from prediabetes to type 2 DM. The objectives of the study are to determine the effects of metformin and placebo on glycemic endpoints, the effects of sitagliptin and metformin on glycemic endpoints, the effects of metformin and placebo on incidence of cardiovascular disease and death, and the effects of sitagliptin and metformin on incidence of cardiovascular disease and death.

Methods

This is a randomized, double-blind, multicenter clinical study that will determine if the combination of metformin and sitagliptin is effective in preventing the progression from prediabetes to type 2 DM. The study will contain two arms (metformin/sitagliptin and metformin/placebo). Primary endpoints include the number of subjects progressing from prediabetes to type 2 DM, the number of cardiovascular events, and the number of deaths. The planned duration of the study is five years, and 410 subjects will be included in each group. Data analyses will include clinically relevant measures (eg, numbers needed to treat and numbers needed to harm) and will be performed according to the intention-to-treat principle.

Results

This study is currently in the process of acquiring research funding.

Conclusions

The SiMePreD study is the first study to investigate the utility of sitagliptin in combination with metformin for the primary prevention of type 2 DM. 

JBASE: Joint Bayesian Analysis of Subphenotypes and Epistasis

MOTIVATION

Rapid advances in genotyping and genome-wide association studies have enabled the discovery of many new genotype-phenotype associations at the resolution of individual markers. However, these associations explain only a small proportion of theoretically estimated heritability of most diseases. In this work, we propose an integrative mixture model called JBASE: joint Bayesian analysis of subphenotypes and epistasis. JBASE explores two major reasons of missing heritability: interactions between genetic variants, a phenomenon known as epistasis and phenotypic heterogeneity, addressed via subphenotyping.

RESULTS

Our extensive simulations in a wide range of scenarios repeatedly demonstrate that JBASE can identify true underlying subphenotypes, including their associated variants and their interactions, with high precision. In the presence of phenotypic heterogeneity, JBASE has higher Power and lower Type 1 Error than five state-of-the-art approaches. We applied our method to a sample of individuals from Mexico with Type 2 diabetes and discovered two novel epistatic modules, including two loci each, that define two subphenotypes characterized by differences in body mass index and waist-to-hip ratio. We successfully replicated these subphenotypes and epistatic modules in an independent dataset from Mexico genotyped with a different platform.

AVAILABILITY AND IMPLEMENTATION

JBASE is implemented in C++, supported on Linux and is available at http://www.cs.toronto.edu/∼goldenberg/JBASE/jbase.tar.gz. The genotype data underlying this study are available upon approval by the ethics review board of the Medical Centre Siglo XXI. Please contact Dr Miguel Cruz at mcruzl@yahoo.com for assistance with the application.

CONTACT

anna.goldenberg@utoronto.ca

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Cereal fibre and type 2 diabetes: time now for randomised controlled trials?

Diet and nutrition are strongly implicated in the aetiology of type 2 diabetes; low dietary fibre intake could be an important factor. Evidence from prospective observational studies has suggested that it may be low cereal fibre intake, rather than low fruit and vegetable fibre intake, which is particularly important. In this issue of Diabetologia (DOI 10.1007/s00125-015-3585-9 ) Kuijsten et al report on the prospective associations between different dietary fibre sources and type 2 diabetes risk in the European Prospective Investigation of Cancer and Nutrition (EPIC)-Interact study and set their findings in context with a meta-analysis of relevant published prospective studies. The results presented strengthen the evidence implicating cereal fibre as an important determinant of type 2 diabetes risk and suggest that randomised controlled trials examining the effect of cereal fibre supplementation on type 2 diabetes risk are now needed.

[Impact of the activation of intention to perform physical activity in type II diabetics: a randomized clinical trial]

Type II diabetes mellitus is a highly prevalent disease among the adult Brazilian population, and one that can be controlled by interventions such as physical activity, among others. The aim of this randomized controlled study was to evaluate the impact of a traditional motivational strategy, associated with the activation of intention theory, on adherence to physical activity in patients with type II, diabetes mellitus who are part of the Unified Health System (SUS). Participants were divided into a control group (CG) and an intervention group (IG). In both groups, the traditional motivational strategy was applied, but the activation of intention strategy was only applied to the IG Group. After a two-month follow-up, statistically significant differences were verified between the groups, related to the practice of walking (p = 0.0050), number of days per week (p = 0.0076), minutes per day (p = 0.0050) and minutes walking per week (p = 0.0015). At the end of the intervention, statistically significant differences in abdominal circumference (p = 0.0048) between the groups were observed. The conclusion drawn is that the activation of intention strategy had greater impact on adherence to physical activity and reduction in abdominal circumference in type II diabetics, than traditional motivational strategy.

Lifestyle interventions for adults with impaired glucose tolerance: a systematic review and meta-analysis of the effects on glycemic control

OBJECTIVE

Previous meta-analyses have demonstrated that lifestyle modification can reduce the blood glucose levels in patients with type 2 diabetes, although the effects of changes in the blood glucose level on impaired glucose tolerance (IGT) remain controversial. This review therefore aimed to determine the efficacy of lifestyle interventions in adults with IGT.

METHODS

We searched the Medline, Cochrane Library, EMBASE and Science Citation Index databases and reference lists of the included articles. Two independent reviewers extracted the data and assessed the quality of the included studies; a total of nine randomized controlled trials met the inclusion criteria. In addition, we tested for trial heterogeneity and calculated the pooled effects size using the random effects model.

RESULTS

The overall interventions were associated with a decline in the 2-hour plasma glucose levels [standardized mean differences (SMD) -0.56; 95% confidence interval (CI), -1.01 to -0.10; I(2), 96.6%]. Moreover, dietary intervention (SMD -0.53; 95% CI -0.77 to -0.28) and physical intervention (SMD -0.42; 95% CI -0.63 to -0.20) were each associated with a decline in the 2-hour plasma glucose levels compared with that observed in the control participants. The overall interventions were associated with a decline in the fasting plasma glucose (FPG) levels (SMD -0.27; 95% CI -0.38 to -0.15; I(2) = 47.1%). In addition, physical intervention (SMD -0.25; 95% CI -0.44 to -0.05) and combined dietary and physical intervention were each associated with a decreased FPG level (SMD -0.28; 95% CI -0.44 to -0.12) compared with that observed in the control participants.

CONCLUSION

Lifestyle modification based on physical or dietary interventions or both is associated with improvements in the 2-hour plasma glucose and FPG levels in IGT patients.

Continuous glucose monitoring system and new era of early diagnosis of diabetes in high risk groups

Continuous glucose monitoring (CGM) systems are an emerging technology that allows frequent glucose measurements to monitor glucose trends in real time. Their use as a diagnostic tool is still developing and appears to be promising. Combining intermittent glucose self-monitoring (SGM) and CGM combines the benefits of both. Significant improvement in the treatment modalities that may prevent the progress of prediabetes to diabetes have been achieved recently and dictates screening of high risk patients for early diagnosis and management of glycemic abnormalities. The use of CGMS in the diagnosis of early dysglycemia (prediabetes) especially in high risk patients appears to be an attractive approach. In this review we searched the literature to investigate the value of using CGMS as a diagnostic tool compared to other known tools, namely oral glucose tolerance test (OGTT) and measurement of glycated hemoglobin (HbA1C) in high risk groups. Those categories of patients include adolescents and adults with obesity especially those with family history of type 2 diabetes mellitus, polycystic ovary syndrome (PCO), gestational diabetes, cystic fibrosis, thalassemia major, acute coronary syndrome (ACS), and after renal transplantation. It appears that the ability of the CGMS for frequently monitoring (every 5 min) glucose changes during real-life settings for 3 to 5 days stretches the chance to detect more glycemic abnormalities during basal and postprandial conditions compared to other short-timed methods.

Incidence of impaired glucose regulation and progression to type 2 diabetes mellitus in the Tayside region of Scotland

This study assessed incidence of impaired glucose regulation (IGR) and progression to type 2 diabetes (T2D) in adults in one region of Scotland using routinely collected health-care data. Incidence of IGR was 2720 per 100,000 person years. Nine percent of IGR patients progressed to T2D in a mean time of 34 months.

Design and baseline characteristics of the PODOSA (Prevention of Diabetes & Obesity in South Asians) trial: a cluster, randomised lifestyle intervention in Indian and Pakistani adults with impaired glycaemia at high risk of developing type 2 diabetes

OBJECTIVES

To describe the design and baseline population characteristics of an adapted lifestyle intervention trial aimed at reducing weight and increasing physical activity in people of Indian and Pakistani origin at high risk of developing type 2 diabetes.

DESIGN

Cluster, randomised controlled trial.

SETTING

Community-based in Edinburgh and Glasgow, Scotland, UK.

PARTICIPANTS

156 families, comprising 171 people with impaired glycaemia, and waist sizes ≥90 cm (men) and ≥80 cm (women), plus 124 family volunteers.

INTERVENTIONS

Families were randomised into either an intensive intervention of 15 dietitian visits providing lifestyle advice, or a light (control) intervention of four visits, over a period of 3 years.

OUTCOME MEASURES

The primary outcome is a change in mean weight between baseline and 3 years. Secondary outcomes are changes in waist, hip, body mass index, plasma blood glucose and physical activity. The cost of the intervention will be measured. Qualitative work will seek to understand factors that motivated participation and retention in the trial and families' experience of adhering to the interventions.

RESULTS

Between July 2007 and October 2009, 171 people with impaired glycaemia, along with 124 family volunteers, were randomised. In total, 95% (171/196) of eligible participants agreed to proceed to the 3-year trial. Only 13 of the 156 families contained more than one recruit with impaired glycaemia. We have recruited sufficient participants to undertake an adequately powered trial to detect a mean difference in weight of 2.5 kg between the intensive and light intervention groups at the 5% significance level. Over half the families include family volunteers. The main participants have a mean age of 52 years and 64% are women.

CONCLUSIONS

Prevention of Diabetes & Obesity in South Asians (PODOSA) is one of the first community-based, randomised lifestyle intervention trials in a UK South Asian population. The main trial results will be submitted for publication during 2013.

TRIAL REGISTRATION

Current controlled trials ISRCTN25729565 (http://www.controlled-trials.com/isrctn/).

Pioglitazone protects HDL(2&3) against oxidation in overweight and obese men

BACKGROUND

The worldwide epidemic of obesity is a major public health concern and is persuasively linked to the rising prevalence of diabetes and cardiovascular disease. Obesity is often associated with an abnormal lipoprotein profile, which may be partly negated by pioglitazone intervention, as this can influence the composition and oxidation characteristics of low-density lipoprotein (LDL). However, as pioglitazone's impact on these parameters within high-density lipoprotein (HDL), specifically HDL(2&3), is absent from the literature, this study was performed to address this shortcoming.

METHODS

Twenty men were randomized to placebo or pioglitazone (30 mg/day) for 12 weeks. HDL(2&3) were isolated by rapid-ultracentrifugation. HDL(2&3)-cholesterol and phospholipid content were assessed by enzymatic assays and apolipoprotein AI (apoAI) content by single-radial immunodiffusion. HDL(2&3) oxidation characteristics were assessed by monitoring conjugated diene production and paraoxonase-1 activity by spectrophotometric assays.

RESULTS

Compared with the placebo group, pioglitazone influenced the composition and oxidation potential of HDL(2&3). Specifically, total cholesterol (P < 0.05), phospholipid (P < 0.001) and apoAI (P < 0.001) were enriched within HDL(2). Furthermore, the resistance of HDL(2&3) to oxidation (P < 0.05) and the activity of paroxonase-1 were also increased (P < 0.001).

CONCLUSIONS

Overall, these findings indicate that pioglitazone treatment induced antiatherogenic changes within HDL(2&3), which may help reduce the incidence of premature cardiovascular disease linked with obesity.

A simple clinical model predicted diabetes progression among prediabetic individuals

We followed 1372 prediabetic individuals aged ≥ 20 years and documented 278 incident diabetes cases. Family history of diabetes, blood pressure, waist, high-density lipoprotein cholesterol, and FPG independently associated with diabetes progression among women. Among men, family history of premature CVD, waist, and FPG remained independently associated with diabetes progression.

Screening for diabetes: hope and despair

This commentary discusses whether screening for type 2 diabetes or earlier normalisation of blood glucose levels or initiation of non-antihyperglycaemic agents or any other diabetes-specific treatment can help reduce the excess associated risks for macrovascular morbidity and mortality. The available data indicate that screening with the sole aim of decreasing the lead time between diagnosis and treatment is very unlikely to reduce these risks. In contrast to macrovascular complications, some microvascular events such as background retinopathy could theoretically be prevented by earlier diagnosis and better glycaemic control, particularly in relatively young type 2 diabetic patients. This, however, remains to be shown in controlled prospective intervention trials.

Tendência da mortalidade por diabetes melito em capitais brasileiras, 1980-2007

OBJETIVO: Analisar o padrão de mortalidade por diabetes nas capitais brasileiras entre 1980 e 2007. MATERIAIS E MÉTODOS: Foram calculadas taxas de mortalidade quadrienais e anuais, padronizadas por idade pela população mundial. Modelos de regressão linear foram estimados para análise da tendência nas capitais. RESULTADOS: No primeiro quadriênio, a taxa mais elevada correspondeu a 42,89/100.000 em Aracaju e, no último, a 54,38/100.000 em São Luís. Foram observadas tendências estatisticamente significativas de incremento na maioria das capitais, embora com diferenças regionais. Belo Horizonte foi a única capital a mostrar tendência de declínio. CONCLUSÕES: Uma parte do incremento observado poderia ser atribuída a melhoras no acesso ao diagnóstico e na certificação da causa de morte, porém diferenças regionais na prevalência de fatores de risco e proteção para a doença possivelmente também estão implicadas. A não disponibilidade de série histórica de casos incidentes impossibilita determinar se esses resultados refletem tendências atuais da incidência do diabetes no Brasil.

Effect of lifestyle intervention for people with diabetes or prediabetes in real-world primary care: propensity score analysis

BACKGROUND

Many lifestyle interventions for patients with prediabetes or type 2 diabetes mellitus (T2DM) have been investigated in randomised clinical trial settings. However, the translation of these programmes into primary care seems challenging and the prevalence of T2DM is increasing. Therefore, there is an urgent need for lifestyle programmes, developed and shown to be effective in real-world primary care. We evaluated a lifestyle programme, commissioned by the Dutch government, for patients with prediabetes or type 2 diabetes in primary care.

METHODS

We performed a retrospective comparative medical records analysis using propensity score matching. Patients with prediabetes or T2DM were selected from ten primary healthcare centres. Patients who received the lifestyle intervention (n = 186) were compared with a matched group of patients who received usual care (n = 2632). Data were extracted from the electronic primary care records. Propensity score matching was used to control for confounding by indication. Outcome measures were exercise level, BMI, HbA1c, fasting glucose, systolic and diastolic blood pressure, total cholesterol, HDL and LDL cholesterol and triglycerides and the follow-up period was one year.

RESULTS

There was no significant difference at follow-up in any outcome measure between either group. The reduction at one year follow-up of HbA1c and fasting glucose was positive in the intervention group compared with controls, although not statistically significant (-0.12%, P = 0.07 and -0.17 mmol/l, P = 0.08 respectively).

CONCLUSIONS

The effects of the lifestyle programme in real-world primary care for patients with prediabetes or T2DM were small and not statistically significant. The attention of governments for lifestyle interventions is important, but from the available literature and the results of this study, it must be concluded that improving lifestyle in real-world primary care is still challenging.

Translating research evidence to service provision for prevention of type 2 diabetes: development and early outcomes of the ‘New life, New you’ intervention

We report the development and early outcomes of an innovative intervention, directed to people at risk of type 2 diabetes, delivered by fitness trainers in leisure and community settings in Middlesbrough, UK. Men and women aged 45 to 65, living in socio-economically disadvantaged areas were assessed for risk of type 2 diabetes and recruited to the intervention. Weight, height, waist circumference and physical activity were measured at baseline and six months. A social marketing campaign attracted 217 recruits. Baseline means (standard deviation; SD) were as follows: age 53.1(5.9) years, FINDRISC-score (a questionnaire-based prospective risk score to predict development of type 2 diabetes) 13.2 (3.3), body mass index 32.9 kgm2 (6.0), physical activity level 49.2 (6.4) self-report metabolic equivalent tasks (MET)-hours/day. Follow-up was completed by 144 participants with mean (SD) reduction in weight −2.2 kg (4.3) (95% confidence interval (CI) −3.0 to −1.5) and waist circumference −5.5 cm (4.5) (95% CI −6.6 to −4.5); increase in physical activity level +5.5 (5.4) (95% CI 4.5–6.4) self report MET-hours/day and variety +1.4 (1.2) (95% CI 1.1–1.6) activity types. High retention and positive outcomes at six months are indications of initial success. The interim results of this real-world intervention are comparable to early intermediate health outcomes in the European Diabetes Prevention Study (EDIPS)-Newcastle randomised controlled trial suggesting potential for translation of lifestyle intervention into practice. Longer term follow-up and controlled evaluation are warranted.

[Diabetes mellitus prevalence and associated factors in adults in Ribeirão Preto, São Paulo, Brazil, 2006: OBEDIARP Project]

To identify diabetes mellitus prevalence and associated factors, a cross-sectional epidemiological study was developed including participants aged 30 years and older living in Ribeirão Preto, São Paulo State, Brazil. Using three-stage cluster sampling, probability weights were applied, resulting in a weighted sample of 2,197 participants. Diabetes mellitus diagnosis was based on previous medical history or World Health Organization (WHO) cut-offs after oral glucose tolerance test. To investigate associated factors, crude and adjusted prevalence ratios were estimated by points and confidence intervals, using Poisson regression. Diabetes mellitus prevalence was 15.02%. After adjusting for potential confounding, factors associated with diabetes mellitus in the final model were: age; family history of diabetes mellitus; waist hip ratio; waist height ratio; number of medicines taken; and use of outpatient services. The results showed high diabetes mellitus prevalence and identified associated factors amenable to intervention.

Reduction of diabetes risk in routine clinical practice: are physical activity and nutrition interventions feasible and are the outcomes from reference trials replicable? A systematic review and meta-analysis

Background

The clinical effectiveness of intensive lifestyle interventions in preventing or delaying diabetes in people at high risk has been established from randomised trials of structured, intensive interventions conducted in several countries over the past two decades. The challenge is to translate them into routine clinical settings. The objective of this review is to determine whether lifestyle interventions delivered to high-risk adult patients in routine clinical care settings are feasible and effective in achieving reductions in risk factors for diabetes.

Methods

Data sources: MEDLINE (PubMed), EMBASE, CINAHL, The Cochrane Library, Google Scholar, and grey literature were searched for English-language articles published from January 1990 to August 2009. The reference lists of all articles collected were checked to ensure that no relevant suitable studies were missed. Study selection: We included RCTs, before/after evaluations, cohort studies with or without a control group and interrupted time series analyses of lifestyle interventions with the stated aim of diabetes risk reduction or diabetes prevention, conducted in routine clinical settings and delivered by healthcare providers such as family physicians, practice nurses, allied health personnel, or other healthcare staff associated with a health service. Outcomes of interest were weight loss, reduction in waist circumference, improvement of impaired fasting glucose or oral glucose tolerance test (OGTT) results, improvements in fat and fibre intakes, increased level of engagement in physical activity and reduction in diabetes incidence.

Results

Twelve from 41 potentially relevant studies were included in the review. Four studies were suitable for meta-analysis. A significant positive effect of the interventions on weight was reported by all study types. The meta-analysis showed that lifestyle interventions achieved weight and waist circumference reductions after one year. However, no clear effects on biochemical or clinical parameters were observed, possibly due to short follow-up periods or lack of power of the studies meta-analysed. Changes in dietary parameters or physical activity were generally not reported. Most studies assessing feasibility were supportive of implementation of lifestyle interventions in routine clinical care.

Conclusion

Lifestyle interventions for patients at high risk of diabetes, delivered by a variety of healthcare providers in routine clinical settings, are feasible but appear to be of limited clinical benefit one year after intervention. Despite convincing evidence from structured intensive trials, this systematic review showed that translation into routine practice has less effect on diabetes risk reduction.

Clinical and economic considerations of antiobesity treatment: a review of orlistat

The objective of this study was to review the current knowledge about the use of orlistat from clinical and economic perspectives, and to assess this drug's public health impact. Weight reduction by current antiobesity drugs, compared to placebo, is at most around 5 kg. Orlistat, the most studied antiobesity drug, is associated with the least-severe adverse effects, but compared with other drugs in its class it also delivers the most modest weight loss versus placebo (less than 3 kg). Orlistat appears to have a favorable risk/benefit profile, and cost-effectiveness ratios seem to be within a range that is generally considered acceptable. In the short-term, orlistat is related to reduced diabetes incidence and to slightly improved blood pressure and lipid profiles. Long-term clinical effects have been largely unstudied, however, and this study did not find reports that considered mortality as an endpoint. Given a very low continuation with orlistat treatment in the population and very modest and, apparently, only short-term clinical effects, orlistat is not likely to have a significant impact on the population health. Public health approaches of improving environmental and social factors to foster healthier food choices and increase physical activity remain essential for addressing the obesity epidemic.

Chinese herbal medicines for people with impaired glucose tolerance or impaired fasting blood glucose

BACKGROUND

Around 308 million people worldwide are estimated to have impaired glucose tolerance (IGT); 25% to 75% of these will develop diabetes within a decade of initial diagnosis. At diagnosis, half will have tissue-related damage and all have an increased risk for coronary heart disease.

OBJECTIVES

The objective of this review was to assess the effects and safety of Chinese herbal medicines for the treatment of people with impaired glucose tolerance or impaired fasting glucose (IFG).

SEARCH STRATEGY

We searched the following databases: The Cochrane Library, PubMed, EMBASE, AMED, a range of Chinese language databases, SIGLE and databases of ongoing trials.

SELECTION CRITERIA

Randomised clinical trials comparing Chinese herbal medicines with placebo, no treatment, pharmacological or non-pharmacological interventions in people with IGT or IFG were considered.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data. Trials were assessed for risk of bias against key criteria: random sequence generation, allocation concealment, blinding of participants, outcome assessors and intervention providers, incomplete outcome data, selective outcome reporting and other sources of bias.

MAIN RESULTS

This review examined 16 trials lasting four weeks to two years involving 1391 participants receiving 15 different Chinese herbal medicines in eight different comparisons. No trial reported on mortality, morbidity or costs. No serious adverse events like severe hypoglycaemia were observed. Meta-analysis of eight trials showed that those receiving Chinese herbal medicines combined with lifestyle modification were more than twice as likely to have their fasting plasma glucose levels return to normal levels (i.e. fasting plasma glucose <7.8 mmol/L and 2hr blood glucose <11.1 mmol/L) compared to lifestyle modification alone (RR 2.07; 95% confidence intervall (CI) 1.52 to 2.82). Those receiving Chinese herbs were less likely to progress to diabetes over the duration of the trial (RR 0.33; 95% CI 0.19 to 0.58). However, all trials had a considerable risk of bias and none of the specific herbal medicines comparison data was available from more than one study. Moreover, results could have been confounded by rates of natural reversion to normal glucose levels.

AUTHORS' CONCLUSIONS

The positive evidence in favour of Chinese herbal medicines for the treatment of IGT or IFG is constrained by the following factors: lack of trials that tested the same herbal medicine, lack of details on co-interventions, unclear methods of randomisation, poor reporting and other risks of bias.

Decision-Analytic Modeling to Evaluate Benefits and Harms of Medical Tests: Uses and Limitations

The clinical utility of medical tests is measured by whether the information they provide affects patient-relevant outcomes. To a large extent, effects of medical tests are indirect in nature. In principle, a test result affects patient outcomes mainly by influencing treatment choices. This indirectness in the link between testing and its downstream effects poses practical challenges to comparing alternate test-and-treat strategies in clinical trials. Keeping in mind the broader audience of researchers who perform comparative effectiveness reviews and technology assessments, the authors summarize the rationale for and pitfalls of decision modeling in the comparative evaluation of medical tests by virtue of specific examples. Modeling facilitates the interpretation of test performance measures by connecting the link between testing and patient outcomes, accounting for uncertainties and explicating assumptions, and allowing the systematic study of tradeoffs and uncertainty. The authors discuss challenges encountered when modeling test-and-treat strategies, including but not limited to scarcity of data on important parameters, transferring estimates of test performance across studies, choosing modeling outcomes, and obtaining summary estimates for test performance data.

Rationale, design and baseline data from the Pre-diabetes Risk Education and Physical Activity Recommendation and Encouragement (PREPARE) programme study: a randomized controlled trial

OBJECTIVE

The PREPARE programme study is a randomized controlled trial which aims to determine whether structured education can be used to increase physical activity and improve glucose tolerance in individuals with impaired glucose tolerance (IGT). This paper outlines the rationale, design and baseline data from the PREPARE programme study.

METHODS

Individuals with IGT were recruited from ongoing diabetes screening programmes. Outcomes included an oral glucose tolerance test, physical activity (piezoelectric pedometer) and psychological determinants.

RESULTS

103 individuals (male n = 65; female n = 38) were recruited, 28% of whom were from a South Asian ethnic background. At baseline the participants' mean age and BMI were 64 +/- 9 years and 29.4 +/- 4.5 kg/m2 respectively. Steps per day were associated with 2-h glucose (p = -0.22, p = 0.03), fasting glucose (p = 0.22, p = 0.04), HDL-cholesterol (p = 0.23, p = 0.02), triglycerides (p = -0.22, p = 0.03) and body fat percentage (p = -0.26, p = 0.01). Mean self-efficacy scores were significantly (p < 0.01) higher for walking than for any other form of exercise. Participants reported high levels of concern about their IGT status but were confident that exercise would help treat/control IGT.

CONCLUSION

This study demonstrates the importance of developing effective physical activity and self-management programmes for individuals with IGT.

PRACTICE IMPLICATIONS

This study provides a detailed framework for the promotion of physical activity in a population identified with an increased risk of developing type 2 diabetes which, if successful, could feasibly be implemented in a primary health care or community setting.

Waiting for diabetes: perceptions of people with pre-diabetes: a qualitative study

OBJECTIVES

This study sought to inform the development of an educational intervention for people with pre-diabetes in the UK by ascertaining individuals' experience of screening and diagnosis, their appraisal of the condition, and experience of health service delivery from diagnosis to 1 year post-diagnosis.

METHODS

Qualitative interviews directed by framework methodology. Fifteen people diagnosed with pre-diabetes from the community (Midlands, UK) as part of a screening programme.

RESULTS

Respondents consistently expressed the need for education and support at diagnosis. Dominating all respondents' narratives was the theme of 'uncertainty', which linked to two further themes of seriousness and taking action. These themes were influenced by respondents' prior experience and appraisal of both diabetes and pre-diabetes and their interpretation of health professionals' attitudes and actions towards them.

CONCLUSIONS

Patients identified as having pre-diabetes currently emphasise their uncertainties about their diagnosis, its physical consequences and subsequent management. Interventions to enable the increasing numbers of individuals with pre-diabetes to manage their health optimally should evolve to address these uncertainties.

PRACTICE IMPLICATIONS

Those delivering services to those at risk of, or diagnosed with, pre-diabetes should be aware of patient needs and tailor care to support and shape perceptions to enhance health-maintaining behaviours.

Different strategies for screening and prevention of type 2 diabetes in adults: cost effectiveness analysis

OBJECTIVE

To compare four potential screening strategies, and subsequent interventions, for the prevention and treatment of type 2 diabetes: (a) screening for type 2 diabetes to enable early detection and treatment, (b) screening for type 2 diabetes and impaired glucose tolerance, intervening with lifestyle interventions in those with a diagnosis of impaired glucose tolerance to delay or prevent diabetes, (c) as for (b) but with pharmacological interventions, and (d) no screening.

DESIGN

Cost effectiveness analysis based on development and evaluation of probabilistic, comprehensive economic decision analytic model, from screening to death.

SETTING

A hypothetical population, aged 45 at time of screening, with above average risk of diabetes.

DATA SOURCES

Published clinical trials and epidemiological studies retrieved from electronic bibliographic databases; supplementary data obtained from the Department of Health statistics for England and Wales, the screening those at risk (STAR) study, and the Leicester division of the ADDITION study.

METHODS

A hybrid decision tree/Markov model was developed to simulate the long term effects of each screening strategy, in terms of both clinical and cost effectiveness outcomes. The base case model assumed a 50 year time horizon with discounting of both costs and benefits at 3.5%. Sensitivity analyses were carried out to investigate assumptions of the model and to identify which model inputs had most impact on the results.

RESULTS

Estimated costs for each quality adjusted life year (QALY) gained (discounted at 3.5% a year for both costs and benefits) were pound14,150 (euro17 560; $27,860) for screening for type 2 diabetes, pound6242 for screening for diabetes and impaired glucose tolerance followed by lifestyle interventions, and pound7023 for screening for diabetes and impaired glucose tolerance followed by pharmacological interventions, all compared with no screening. At a willingness-to-pay threshold of pound20,000 the probability of the intervention being cost effective was 49%, 93%, and 85% for each of the active screening strategies respectively.

CONCLUSIONS

Screening for type 2 diabetes and impaired glucose tolerance, with appropriate intervention for those with impaired glucose tolerance, in an above average risk population aged 45, seems to be cost effective. The cost effectiveness of a policy of screening for diabetes alone, which offered no intervention to those with impaired glucose tolerance, is still uncertain.

Prevention of type 2 diabetes: a review

One of the major public health challenges of the 21st century is type 2 diabetes. WHO estimates that by 2025 as many as 200-300 million people worldwide will have developed the disease. A distressing increase in children is perhaps the most alarming sign of something going wrong. Roughly half of the risk of type 2 diabetes can be attributed to environmental exposure and the other half to genetics. Central themes for prevention are the risk factors overweight, sedentary lifestyle, certain dietary components and perinatal factors. Overweight is the most critical risk factor, and should be targeted for prevention of type 2 diabetes especially among children and youths. Ethnicity and perinatal factors are also worth considering. Today we know that prevention helps. In the US Diabetes Prevention Programme for high risk individuals, there was a 58% relative reduction in the progression to diabetes in the lifestyle group compared with the controls. Within the lifestyle group, 50% achieved the goal of more than 7% weight reduction, and 74% maintained at least 150 min of moderately intense activity each week. This review discusses different forms of prevention, and proposes first of all to target people with Impaired Glucose Tolerance with increasing activity and altering dietary factors. And secondly, population-based measures to encourage increased physical activity and decreased consumption of energy-dense foods are important, and may target school children and young people, certain ethnic groups and women with gestational diabetes.

Pharmacological and lifestyle interventions to prevent or delay type 2 diabetes in people with impaired glucose tolerance: systematic review and meta-analysis

OBJECTIVE

To quantify the effectiveness of pharmacological and lifestyle interventions to prevent or delay type 2 diabetes in people with impaired glucose tolerance.

DATA SOURCES

Medline, Embase, and the Cochrane library searched up to July 2006. Expert opinions sought and reference lists of identified studies and any relevant published reviews checked.

STUDY SELECTION

Randomised controlled trials that evaluated interventions to delay or prevent type 2 diabetes in individuals with impaired glucose tolerance.

RESULTS

21 trials met the inclusion criteria, of which 17, with 8084 participants with impaired glucose tolerance, reported results in enough detail for inclusion in the meta-analyses. From the meta-analyses the pooled hazard ratios were 0.51 (95% confidence interval 0.44 to 0.60) for lifestyle interventions v standard advice, 0.70 (0.62 to 0.79) for oral diabetes drugs v control, 0.44 (0.28 to 0.69) for orlistat v control, and 0.32 (0.03 to 3.07) for the herbal remedy jiangtang bushen recipe v standard diabetes advice. These correspond to numbers needed to treat for benefit (NNTB) and harm (NNTH) of 6.4 for lifestyle (95% credible interval, NNTB 5.0 to NNTB 8.4), 10.8 for oral diabetes drugs (NNTB 8.1 to NNTB 15.0), 5.4 for orlistat (NNTB 4.1 to NNTB 7.6), and 4.0 for jiangtang bushen (NNTH 16.9 to NNTB 24.8).

CONCLUSIONS

Lifestyle and pharmacological interventions reduce the rate of progression to type 2 diabetes in people with impaired glucose tolerance. Lifestyle interventions seem to be at least as effective as drug treatment.

Antidiabetic agents in subjects with mild dysglycaemia: prevention or early treatment of type 2 diabetes?

Besides lifestyle, various pharmacological treatments have proven their efficacy to reduce the incidence of type 2 diabetes in high-risk individuals, especially in those with impaired glucose tolerance (IGT) and/or impaired fasting glucose (IFG). Major placebo-controlled clinical trials demonstrated favourable effects of various glucose-lowering drugs generally used for the treatment of type 2 diabetes, i.e. metformin, acarbose and thiazolidinediones (glitazones). These trials showed a lower rate of progression to overt diabetes and a higher regression rate to a normal glucose status with active treatment as compared to placebo after a follow up of several years. Ongoing trials should confirm such a favourable effect with those drugs and may demonstrate a similar protective effect with other pharmacological approaches such as glinides or even basal insulin regimen. However, the reported favourable effects were generally observed while the subjects were still on treatment, and partially vanished after a rather short period of wash-out of several weeks. Therefore, the distinction between a true preventing effect and simply a masking effect is difficult with glucose-lowering drugs. In addition, as type 2 diabetes is a progressive disease, it is still questionable whether the effect corresponds to a prevention effect or only to a postponing of the development of the disease. Owing to the pathophysiology of the disease, the only way to block the progression of type 2 diabetes is probably to avoid the progressive loss of beta-cell function and/or mass. Whatsoever, these data obtained in large clinical trials bring further argument to support early treatment of diabetes, even at a prediabetic state, in order to stop the vicious circle leading to an inevitable deterioration of glycaemia in predisposed subjects.

Is prevention of Type-2 diabetes feasible and efficient in primary care? A systematic PubMed review

AIM

To answer: (1) Do we have effective treatments to improve prognosis for those identified at risk of Type-2 diabetes? (2) Will prevention be cost-effective?

METHODS

A systematic search was done in PubMed using the following search strategy: "diabetes AND prevention AND (IFG OR IGT)". Restrictions were: "English, Meta-Analysis, Randomized Controlled Trial, Review, Humans".

RESULTS

Few randomised controlled preventive trials were found. Almost all were done in research settings in people with high risk of developing Type-2 diabetes. It seems possible to either delay or prevent Type-2 diabetes through lifestyle interventions and medication. Cost-utility analyses are few in number and come to very different conclusions as to whether health policy should promote prevention of Type-2 diabetes.

CONCLUSION

Intervention studies using lifestyle counselling and drug therapy in research settings illustrate promising results with lowering of the incidence of Type-2 diabetes, meaning that Type-2 diabetes can be delayed or prevented. It is, however, questionable whether these interventions are cost-effective. We need studies in routine clinical settings evaluating morbidity, mortality and cost-effectiveness as primary outcomes. While waiting for these studies to prove cost-effective, patients with pre-diabetes should be treated according to their 10-year risk of cardiovascular disease following present guidelines.

Type 2 diabetes and inheritance: what information do diabetes organizations provide on the Internet?

AIMS

The worldwide epidemic of Type 2 diabetes necessitates preventive actions. Providing information to high-risk populations is key. In an international comparison of websites, we aimed to investigate the presence and quality of information provided by diabetes organizations on inheritance of Type 2 diabetes and the benefits of a healthy lifestyle targeted at those with a family history or belonging to a specific ethnic population.

METHODS

All websites included in the International Diabetes Federation member list in English, German, French, Dutch, Spanish, Portuguese, Swedish, Norwegian, Finnish, Danish and Japanese were included for assessment. Using qualitative content analysis, we reviewed 34 websites which provided health-related information on diabetes.

RESULTS

Most websites mention family history as a risk factor. However, an explanation of the interaction of lifestyle factors and increased genetic susceptibility is lacking. Ethnicity is mentioned in only half of the sites describing risk factors. Although most websites do provide information on the importance of a healthy lifestyle, they do not address specific high-risk groups. Only two websites encourage Type 2 diabetic patients to inform family members of the familial character of diabetes.

CONCLUSIONS

Information on inheritance of Type 2 diabetes and prevention specifically targeted at high-risk groups on the Internet by diabetes organizations is often of poor quality or indeed is lacking. Efforts should be made to disseminate information on heredity of Type 2 diabetes and preventive options to the general public and high-risk populations.

Metabolic monitoring for patients treated with antipsychotic medications

OBJECTIVES

Metabolic side effects of antipsychotic treatment include weight gain, dyslipidemia and increased susceptibility to diabetes. Patients with schizophrenia have increased coronary heart disease mortality and reduced life expectancy. There is an urgent clinical need to monitor antipsychotic-treated patients for metabolic disturbance. Our objectives were to review published international monitoring guidelines, establish goals for metabolic monitoring, and make recommendations for practice.

METHOD

We reviewed the major published consensus guidelines for metabolic monitoring of patients treated with antipsychotic medications and selectively reviewed practice guidelines for the management of diabetes, dyslipidemia, and hypertension.

RESULTS

Patients with serious mental illness have markedly elevated rates of metabolic disturbance and limited access to general medical care. Monitoring, but not necessarily medical treatment of metabolic disorder, falls within the scope of psychiatric practice and should include screening for metabolic disturbance as well as tracking the effects of antipsychotic treatment. In addition, psychiatrists and psychiatric services should work toward facilitating patients' access to medical care. There is considerable consensus in the published guidelines. Areas of dissent include which patients to monitor, the utility of glucose tolerance testing, and the point at which to consider switching antipsychotics.

CONCLUSION

We encourage clinicians to adopt a structured system for conducting and recording metabolic monitoring and to develop collaborations with family physicians, diabetes specialists, dieticians, and recreation therapists to facilitate appropriate medical care for antipsychotic-treated patients.

Novel mechanism for plasma glucose-lowering action of metformin in streptozotocin-induced diabetic rats

To better understand the insulin-independent plasma glucose-lowering action of metformin, we used streptozotocin (STZ)-induced diabetic rats to investigate the possible mechanisms. Oral intake of metformin decreased the plasma glucose of STZ-induced diabetic rats with a parallel increase of plasma beta-endorphin-like immunoreactivity (BER). Mediation of opioid mu-receptors in the action of metformin was identified by the blockade of receptors with antagonist in STZ-induced diabetic rats and the failure of action in opioid mu-receptor knockout diabetic mice. Release of BER from adrenal glands by metformin was characterized, using bilateral adrenalectomy and the release of BER from isolated adrenal medulla of STZ-induced diabetic rats. Repeated treatment with metformin in STZ-induced diabetic rats increased the mRNA and protein levels of GLUT-4 in soleus muscle that was blocked by naloxonazine. Reduction of the mRNA or protein levels of hepatic PEPCK was also impeded in the same group of STZ-induced diabetic rats. In conclusion, our results provide novel mechanisms for the plasma glucose-lowering action of metformin, via an increase of beta-endorphin secretion from adrenal glands to stimulate opioid mu-receptor linkage, leading to an increase of GLUT-4 gene expression and an attenuation of hepatic PEPCK gene expression in STZ-induced diabetic rats.

Effect of bezafibrate on incidence of type 2 diabetes mellitus in obese patients

AIMS

To assess the effect of fibric acid derivative bezafibrate on incidence of type 2 diabetes in obese patients over a median 6.3 years follow-up period.

METHODS AND RESULTS

The study sample comprised 339 non-diabetic obese patients (body mass index > or = 30.0 kg/m2) aged 42-74. Patients received either bezafibrate retard 400 mg (178 patients) or placebo (161 patients) once daily. Development of new diabetes was recorded in 98 patients: in 56 (37.0%) from the placebo group vs. 42 (27.1%) from the bezafibrate group, (P log-rank=0.01). The median time (interquartile range) until onset of new diabetes was significantly delayed in patients on bezafibrate when compared with those on placebo: 4.0 (2.1-5.0) vs. 2.0 (0.5-3.5) years, P=0.002. Multivariable analysis identified bezafibrate treatment as an independent predictor of reduced risk of new diabetes with hazard ratio (HR) 0.59 [95% confidence interval (CI) 0.39-0.91]. Other significant variables associated with future overt type 2 diabetes in obese patients were triglycerides (50 mg/dL increment) with HR 1.15 (95% CI 1.02-1.28) and fasting glucose (10 mg/dL increment) with HR 2.27 (95% CI 1.83-2.81).

CONCLUSION

Bezafibrate, when compared with placebo, reduced the incidence and delayed the onset of type 2 diabetes in obese patients over a long-term follow-up period.

A systematic review of drug therapy to delay or prevent type 2 diabetes

OBJECTIVE

To systematically review the evidence for the prevention of type 2 diabetes by pharmacological therapies.

RESEARCH DESIGN AND METHODS

Randomized controlled trials and cohort studies examining the effect of oral hypoglycemic agents, antiobesity agents, antihypertensive agents, statins, fibrates, and estrogen on the incidence of type 2 diabetes were identified from MEDLINE, EMBASE, the Cochrane Controlled Trials Registry, and searches of reference lists. Two reviewers independently assessed studies for inclusion and performed data extraction.

RESULTS

Ten studies of oral hypoglycemic agents and 15 studies of nonoral hypoglycemic agents were found. Oral hypoglycemic agents and orlistat are the only drugs that have been studied in randomized controlled trials with diabetes incidence as the primary end point. In the largest studies of 2.5-4.0 years' duration, metformin (relative risk [RR] 0.69, 95% CI 0.57-0.83), acarbose (0.75, 0.63-0.90), troglitazone (0.45, 0.25-0.83), and orlistat (hazard ratio [HR] 0.63, 95% CI 0.46-0.86) have all been shown to decrease diabetes incidence compared with placebo; however, follow-up rates varied from 43 to 96%. Current evidence for statins, fibrates, antihypertensive agents, and estrogen is inconclusive. In addition, the critical question of whether drugs are preventing, or simply delaying, onset of diabetes remains unresolved.

CONCLUSIONS

Currently, no single agent can be definitively recommended for diabetes prevention. Future studies should be designed with diabetes incidence as the primary outcome and should be of sufficient duration to differentiate between genuine diabetes prevention as opposed to simple delay or masking of this condition.

Renin-angiotensin system inhibition prevents type 2 diabetes mellitus

Most individuals with arterial hypertension or congestive heart failure are insulin-resistant and at a higher risk of developing type 2 diabetes (T2DM). The inhibition of the renin-angiotensin system (RAS), using an angiotensin converting enzyme inhibitor (ACEI) or a selective angiotensin receptor AT1 blocker (ARB), may exert favourable metabolic effects capable of preventing T2DM in high risk individuals. We performed a meta-analysis of randomised clinical trials (RCTs) assessing the effects of RAS inhibition on the incidence of new cases of T2DM in patients with arterial hypertension or congestive heart failure. Ten RCTs with cardiovascular prognosis as primary endpoints analysed the incidence of T2DM as secondary endpoints or as post-hoc analysis after a mean follow-up of 1 to 6 years: five with an ACEI and five with an ARB, compared with a placebo (n=4) or a reference drug (beta-blocker or diuretic: n=5; amlodipine: n=2). Eight RCTs concerned hypertensive patients: STOP Hypertension-2 (lisinopril or enalapril vs beta-blocker or diuretic), CAPPP (captopril vs thiazide or beta-blocker), HOPE (ramipril vs placebo), ALLHAT (lisinopril vs chlorthalidone and lisinopril vs amlodipine), LIFE (losartan vs atenolol), SCOPE (candesartan vs placebo), ALPINE (candesartan vs placebo) and VALUE (valsartan vs amlodipine). Two RCTs concerned patients with congestive heart failure: SOLVD (enalapril vs placebo) and CHARM-overall programme (candesartan vs placebo). Overall, 2 675 new cases of T2DM (7.40%) were observed in the group of 36 167 patients receiving a treatment with ACEI or ARA as compared with 3 842 events (9.63%) in the group of 39 902 control patients. A mean weighed relative risk reduction of new T2DM of 22% (95% CI: 18, 26; p<0.00001) was observed after RAS inhibition. The beneficial effect was similar with ACEIs and with ARBs as well as in patients with hypertension and in those with heart failure, and was also present whatever the comparator (placebo or beta-blockers/diuretics or amlodipine). The number needed-to-treat to avoid one new case of T2DM averaged 45 patients over 4-5 years. In conclusion, RAS inhibition consistently and significantly reduces the incidence of T2DM in individuals with arterial hypertension or with congestive heart failure. Considering the pandemic of T2DM, such pharmacological approach deserves further attention among the strategies aiming at preventing T2DM.