Global burden of diabetes, 1995-2025: prevalence, numerical estimates, and projections

Type 2 diabetes in Tirana City, Albania: a rapid increase in a country in transition

AIMS

To determine how the prevalence of Type 2 diabetes mellitus has changed in Tirana, the capital of Albania, over 20 years.

METHODS

Cluster sampling was used to select 700 households including 1540 adults 25 years of age and over in Tirana City, Albania in 2001.

RESULTS

Of 1540 potential subjects, 1120 participated (response rate 72.7%). Using the 1985 WHO criteria to provide comparability with earlier data, the overall prevalence of Type 2 diabetes mellitus in the age group 25+ was 6.3% (95% confidence interval 4.8-7.7); 6.9% (4.8-9.1%) male; 5.6% (3.8-7.5%) female. The age-adjusted prevalence in those aged 25+ was 5.4%. Of respondents, 3.4% were known to have diabetes, and 2.9% were newly identified through the survey. The prevalence of diabetes increased with age, although among men there was a slight decline after age 65. Impaired glucose tolerance was found in a further 2.9% of respondents, again increasing with age. The prevalence of diabetes has increased significantly since 1980, doubling in the age group 50+. Use of the 1999 WHO diagnostic criteria produces a higher unadjusted prevalence, at 9.7% (8-11.4%). In a logistic regression model, obesity and family history were independent determinants of the probability of having diabetes. Among those known to have diabetes, control was poor.

CONCLUSIONS

The prevalence of diabetes in Albania has increased rapidly, consistent with what has been seen in other countries undergoing rapid modernization. It is likely to increase further in the future, with important implications for health policy.

Managing Type 2 Diabetes Mellitus in Patients with Obesity

Obesity is the most important modifiable risk factor for type 2 diabetes mellitus and most patients with diabetes are overweight or obese. It is well known that excess bodyweight induces or aggravates insulin resistance, which is a characteristic feature of type 2 diabetes. Thus, bodyweight plays a central role in the prevention and treatment of diabetes. Recent data suggest that lifestyle intervention in patients with impaired glucose tolerance results in an impressive reduction in the conversion to overt diabetes, which is greater than the effect of early intervention with drugs such as metformin or acarbose. The prevention of diabetes has been shown to be associated with the extent of weight loss. In patients with type 2 diabetes, weight loss by any means is followed by an improvement of metabolic control and associated risk factors. The most appropriate recommendation for obese patients with type 2 diabetes is a nutritionally balanced, moderately hypocaloric diet with a reduced intake of saturated fat and an increase in physical activity. If this standard approach is only partly successful or not at all, additional strategies such as weight-lowering drugs, very low-calorie diets for limited periods of up to 12 weeks, and, for severely obese patients, bariatric surgery should be carefully considered. A large body of data suggests that such measures can be very effective in this patient group by improving metabolic disturbances and blood pressure. However, it is extremely important for the long-term outcome that the treatment is tailored to the needs and wishes of the individual patient. There is growing agreement that due to the low success rate of conventional therapies and the overwhelming benefit from weight loss, more determined and aggressive strategies may be appropriate to achieve the central goal of weight reduction in obese patients with type 2 diabetes.

Cost-of-illness studies in diabetes mellitus

Several cost-of-illness (COI) studies related to diabetes mellitus have been performed over the last three decades. This review examines the results of these COI studies, identifies the strengths and limitations of the various methods utilised, and suggests future research that will help determine the economic burden of diabetes more accurately. Diabetes imposes a large economic burden on society. The economic cost of diabetes is estimated to be as much as dollars US 100 billion per year in the US alone (1997 values). This estimated cost has increased notably over time, primarily due to price inflation and the increasing prevalence of diabetes. Differing methodologies have significantly influenced the cost estimates and made comparisons between COI studies problematic. For example, early reports tended to rely exclusively on data where diabetes was listed as the primary diagnosis or reason for healthcare use. To better capture the costs associated with diabetes-related complications, later studies have included costs related to diabetes as a secondary or tertiary diagnosis using the attributable risk methodology. Given the types of long-term complications that are associated with diabetes, attempts at capturing these secondary costs are appropriate. However, estimates of attributable risk can be limited by the epidemiological data currently available. The tremendous economic burden of diabetes makes the disease an important clinical and public health problem. In order to formulate an effective response to this problem, it is important to track future economic trends as healthcare delivery, morbidity and mortality patterns evolve. Future research efforts should focus on refining methods to estimate costs, improving the interpretation of study findings, and facilitating comparisons between studies.

White blood cell count is associated with macro- and microvascular complications in chinese patients with type 2 diabetes

OBJECTIVES

There are close associations among raised white blood cell (WBC) count, coronary heart disease, and metabolic syndrome in the general population. The association between WBC count and vascular complications of diabetes has not been explored. We carried out a cross-sectional cohort study to determine the association between WBC count and the presence of macro- and microvascular complications in type 2 diabetes.

RESEARCH DESIGN AND METHODS

In this study, 3,776 patients with type 2 diabetes and normal WBC count (3.5-12.5 x 10(9)/l) underwent a comprehensive assessment of complications and cardiovascular risk factors based on the European DiabCare protocol. Demographic and anthropometric parameters were recorded. Metabolic profiles, including complete blood picture and urinary albumin excretion, were measured.

RESULTS

Patients with higher WBC counts (categorized into quintiles) had adverse metabolic profiles as evidenced by higher blood pressure, BMI, HbA(1c), fasting plasma glucose, LDL cholesterol, triglycerides, and urinary albumin excretion, but lower HDL cholesterol (all P <0.001 for trend). The prevalence of macro- and microvascular complications increased in a dosage-related manner with WBC count. After adjustments for smoking and other known cardiovascular risk factors, a 1-unit (1 x 10(9)/l) increment of WBC count was associated with a 15.8% (95% CI 9.3-22.6; P < 0.001) and 12.3% increase (5.8-19.1; P < 0.001) in the prevalence of macro- and microvascular complications, respectively.

CONCLUSIONS

Elevated WBC count, even within the normal range, is associated with both macro- and microvascular complications in type 2 diabetes. Chronic inflammation, as indicated by a higher WBC count, may play a linkage role in the development of macro- and microvascular complications in diabetes.

Modeling the efficiency of reaching a target intermediate end point: a case study in type 2 diabetes in the United States

OBJECTIVE

The objective of this study was to describe an approach to modeling the efficiency of an intervention by focusing on an established intermediate end point directly. A case study addresses the economic efficiency of obtaining dual glycemic control over time, according to initial choice of treatment.

METHODS

From the perspective of a payer in the United States, instead of the usual approach of basing the model on projecting long-term diabetic complications from glycemic control, this model focuses directly on glycemic control. Treatment changes and associated health-care utilization needed to address postprandial glucose. After assigning each of 10000 drug-naïve patients, HbA1c, age, race, and sex based on distributions from a randomized clinical trial, the model applies the efficacy of nateglinide compared to metformin. Sensitivity analyses were carried out for all parameters. Costs are reported in year 2000 US dollars and discounted at 3%.

RESULTS

In the base case, starting on nateglinide and increasing the time in dual glycemic control over 3 years by 2.4 months led to savings of US dollars 295 compared to starting on metformin. Savings increased with stricter treatment criteria but decreased if glycemic control was better initially.

CONCLUSIONS

This study illustrates the use of an efficiency model that focuses directly on the relevant short-term end point: glycemic control. Starting patients with nateglinide is shown to be an efficient way of obtaining dual glycemic control during the first 3 years of treatment.

Calcium antagonists in patients with type 2 diabetes and hypertension

Hypertension is twice as common in patients with diabetes compared to those without diabetes. It accounts for up to 75% of cardiovascular disease risk leading to the substantial increase in morbidity and mortality. Control of blood pressure in people with diabetes has been shown in randomized controlled trials to decrease cardiovascular risk and improve outcome especially in preventing stroke. A target blood pressure goal of <130/80 mm Hg is currently recommended for patients with diabetes. However, less than 1/3 of these patients achieve such a goal. This is in part due to the inherent difficulty in controlling blood pressure in these patients where hypertension is usually associated with increased salt sensitivity, volume expansion and isolated systolic hypertension. Therefore, patients with diabetes usually require multiple medications for optimal blood pressure control. Calcium channel antagonists have been shown in large clinical trials to be both safe and effective in controlling blood pressure in diabetic patients and will continue to play a major role in the management of hypertension in this population, particularly in the combination therapy that these patients usually require.

Randomized controlled trial of a new dietary education program to prevent type 2 diabetes in a high-risk group of Japanese male workers

OBJECTIVE

The aim of this study was to assess the effectiveness of a new dietary education (NDE) program in reducing plasma glucose (PG) levels in Japanese male workers at high risk for type 2 diabetes through a randomized controlled trial.

RESEARCH DESIGN AND METHODS

We randomly assigned 173 high-risk men (mean age, 55 years) to either the NDE or the control (conventional dietary education) group. Each subject in the NDE group received two individualized interventions especially aimed at reducing total energy intake at dinner by modifying dietary intake. The control group received conventional group counseling. An "overintake/underintake fraction" for total energy intake was used to measure the status of dietary intake. Our hypothesis was that the NDE group would have a 10% decrease in 2-h PG 1 year after the start of the education. Outcome measures were compared with ANCOVA by adjusting for baseline values.

RESULTS

The NDE group had a significantly lower total energy intake at dinner and daily than the control group. The adjusted differences in changes from baseline in the absolute value of the 'overintake/underintake fraction' were -15.3% (95% CI -24.6 to -6.0%, P = 0.002) for dinner and -6.0% (-9.8 to -2.2%, P = 0.002) for daily [corrected]. The NDE group had a decreased 2-h PG after 1 year, whereas that value was increased in the control group. The adjusted difference in the percent change of 2-h PG was significant (-15.2%, -22.0 to -8.4%, P < 0.001).

CONCLUSIONS

The NDE was shown to reduce glucose levels in high-risk subjects for type 2 diabetes.

Diabetes is associated with subclinical functional limitation in nondisabled older individuals: the Health, Aging, and Body Composition study

OBJECTIVE

The aim of this study was to examine the role of comorbid conditions and body composition in the association between diabetes and subclinical functional limitation, an indication of early functional decline, in well-functioning older individuals.

RESEARCH DESIGN AND METHODS

This was a cross-sectional analysis of 3,075 well-functioning black and white men and women aged 70-79 years, enrolled in the Health, Aging, and Body Composition study. Diabetes was defined by self-report and/or hypoglycemic medication use or fasting glucose >/=126 mg/dl. Subclinical functional limitation was defined using self-report of capacity and objective performance measures. Comorbid conditions were identified by self-reported diagnoses, medication use, and clinical measures. Body composition measures included anthropometry and total fat (dual X-ray absorptiometry).

RESULTS

Of 2,926 participants, 1,252 (42.8%) had subclinical functional limitation at baseline. Among 2,370 individuals without diabetes, 40% had subclinical functional limitation, whereas the prevalence was 53% among the 556 diabetic participants with an age/sex/race-adjusted odds ratio (OR) 1.70 (95% CI 1.40-2.06). This association remained significant when adjusted for body composition measures (OR 1.54 [1.26-1.88]), diabetes-related comorbidities, and other potential confounders (OR 1.40 [1.14-1.73]). In the fully adjusted model, consideration of HbA(1c) (< or >/=7%) and diabetes duration showed that poor glycemic control in diabetic individuals explained the association with subclinical functional limitation.

CONCLUSIONS

In a well-functioning older population, diabetes is associated with early indicators of functional decline, even after accounting for body composition and diabetes-related comorbidities. Poor glycemic control contributes to this relationship. Whether improvement in glycemic control in older people with diabetes would change this association should be tested.

Hypertension in people with Type 2 diabetes: knowledge-based diabetes-specific guidelines

The International Diabetes Federation (Europe) has updated these guidelines on hypertension management specifically in Type 2 diabetes in the light of recent results of the first prospective, randomized controlled studies to investigate clinical outcomes in people with diabetes and hypertension. The guidelines are knowledge based, i.e. based not only on evidence originating from clinical trials, but also from epidemiological and pathophysiological studies. A successful management strategy requires the following components: 1. Regular surveillance to detect developing hypertension and other cardiovascular (CV) risk factors. 2. Considering more frequent monitoring and review of CV risk factors if any single blood pressure (BP) measurement > 140/85 mmHg (or 130/75 if microalbuminuria); when appropriate, using ambulatory or home monitoring to establish the baseline BP. 3. Considering other CV risk factors, such as a raised albumin excretion rate, in setting the intervention threshold. 4. Individualizing the target BP in accordance with other CV risk factors. 5. Agreeing lifestyle and therapeutic interventions with the patient, with education and empowerment as required. 6. Implementing lifestyle modifications, including controlling calorie, salt and alcohol intake, increased physical activity, weight control and smoking cessation. 7. Therapeutic strategy: the primary goal of therapy is to reduce BP markedly. Combination therapy is often necessary, e.g. an angiotensin converting enzyme (ACE) inhibitor and a diuretic. Some classes are particularly useful for certain patients, notably longer-acting ACE inhibitors, angiotensin 2 receptor antagonists (A2RAs) and calcium antagonists in those at risk of diabetic nephropathy, loop diuretics and thiazides in those at risk of hyperkalaemia, beta-blockers and calcium antagonists (except short-acting dihydropyridines) in patients with angina, beta-blockers and ACE inhibitors after a myocardial infarction or in those with left ventricular dysfunction, and thiazide diuretics and long-acting dihydropyridine calcium antagonists for isolated systolic hypertension. A2RAs should be particularly considered when ACE inhibitors are not tolerated. alpha 1-Blockers should not be considered first line in the absence of outcome data. Cost of drugs will modify these strategies in developing countries. 8. Monitoring response to therapies and, if target levels are not achieved, either intensifying drug therapy if the CV risk justifies it, or reassessing the target. 9. Maintaining a quality assurance strategy. This strategy is summarized in a simple, practical management algorithm.

Mitochondrial metabolism and type-2 diabetes: a specific target of metformin

Several links relate mitochondrial metabolism and type 2 diabetes or chronic hyperglycaemia. Among them, ATP synthesis by oxidative phosphorylation and cellular energy metabolism (ATP/ADP ratio), redox status and reactive oxygen species (ROS) production, membrane potential and substrate transport across the mitochondrial membrane are involved at various steps of the very complex network of glucose metabolism. Recently, the following findings (1) mitochondrial ROS production is central in the signalling pathway of harmful effects of hyperglycaemia, (2) AMPK activation is a major regulator of both glucose and lipid metabolism connected with cellular energy status, (3) hyperglycaemia by inhibiting glucose-6-phosphate dehydrogenase (G6PDH) by a cAMP mechanism plays a crucial role in NADPH/NADP ratio and thus in the pro-oxidant/anti-oxidant cellular status, have deeply changed our view of diabetes and related complications. It has been reported that metformin has many different cellular effects according to the experimental models and/or conditions. However, recent important findings may explain its unique efficacy in the treatment of hyperglycaemia- or insulin-resistance related complications. Metformin is a mild inhibitor of respiratory chain complex 1; it activates AMPK in several models, apparently independently of changes in the AMP-to-ATP ratio; it activates G6PDH in a model of high-fat related insulin resistance; and it has antioxidant properties by a mechanism (s), which is (are) not completely elucidated as yet. Although it is clear that metformin has non-mitochondrial effects, since it affects erythrocyte metabolism, the mitochondrial effects of metformin are probably crucial in explaining the various properties of this drug.

Combined effects of PPARγ2 P12A and PPARα L162V polymorphisms on glucose and insulin homeostasis: the Québec Family Study

Peroxisome proliferator-activated receptors gamma2 and alpha are nuclear factors known to be important regulators of lipid and glucose metabolism. Two polymorphisms, namely PPARgamma2 P12A and PPARalpha L162V, were investigated for their individual and interaction effects on glucose and insulin homeostasis. Genotypes were determined in 663 nondiabetic adults participating in the Québec Family Study and who underwent an oral glucose tolerance test (OGTT). The insulin and C-peptide areas under the curve (AUC) following the OGTT were higher in subjects carrying the PPARalpha V162 allele compared to homozygous for the L162 allele. When subjects were grouped according to both polymorphisms, higher levels of insulin and C-peptide during the OGTT were observed for those carrying the PPARalpha V162 allele except when they carry at the same time the PPARgamma2 A12 allele. Thus, the PPARgamma2 A12 allele seems protective against the deleterious effect of the PPARalpha V162 allele. Furthermore, a significant gene-gene interaction was observed for the acute (0-30 min) (p<0.001) and the total (p=0.05) C-peptide AUC following the OGTT. These results provide evidence of a gene-gene interaction in the regulation of plasma glucose-insulin homeostasis, and emphasize that these interactions need to be taken into account when dissecting the genetic etiology of complex disorders.

Usefulness of electronic databases for the detection of unrecognized diabetic patients

Background

Even mild hyperglycemia is associated with future acute and chronic complications. Nevertheless, many cases of diabetes in the community go unrecognized. The aim of the study was to determine if national electronic patient records could be used to identify patients with diabetes in a health management organization.

Methods

The central district databases of Israel's largest health management organization were reviewed for all patients over 20 years old with a documented diagnosis of diabetes mellitus (DM) in the chronic disease register or patient file (identified diabetic patients) or a fasting serum glucose level of >126 mg/100 ml according to the central laboratory records (suspected diabetic patients). The family physicians of the patients with suspected diabetes were asked for a report on their current diabetic status.

Results

The searches yielded 1,694 suspected diabetic patients; replies from the family physicians were received for 1,486. Of these, 575 (38.7%) were confirmed to have diabetes mellitus. Their addition to the identified patient group raised the relative rate of diabetic patients in the district by 3.2%.

Conclusion

Cross-referencing existing databases is an efficient, low-cost method for identifying hyperglycemic patients with unrecognized diabetes who require preventive treatment and follow-up. This model can be used to advantage in other clinical sites in Israel and elsewhere with fully computerized databases.

Nutrition and prevention of type 2 diabetes

In recent years, the prevalence of type 2 diabetes has increased alarmingly worldwide, giving diabetes the dimension of an epidemic. Striking parallel increases in the prevalence of obesity reflect the importance of body fatness as a contributing factor to diabetes incidence. Moreover, it has been estimated that up to 75% of the risk of type 2 diabetes is attributable to obesity. Recent clinical trials and observational epidemiologic studies demonstrate the efficacy of lifestyle changes, including decreased energy intake, decreased fat intake, and weight loss, as well as regular participation in physical activity, in improving insulin sensitivity (SI) and reducing the risk of diabetes. This review evaluates evidence of the effect of diet on insulin resistance, insulin secretion, and glucose tolerance, and reflects on directions for future work toward primary prevention of type 2 diabetes.

Dietary, evolutionary, and modernizing influences on the prevalence of type 2 diabetes

An evolutionary perspective is used to elucidate the etiology of the current epidemic of type 2 diabetes estimated at 151 million people. Our primate legacy, fossil hominid, and hunting-gathering lifestyles selected for adaptive metabolically thrifty genotypes and phenotypes are rendered deleterious through modern lifestyles that increase energy input and reduce output. The processes of modernization or globalization include the availability and abundance of calorically dense/low-fiber/high-glycemic foods and the adoption of sedentary Western lifestyles, leading to obesity among both children and adults in developed and developing countries. These trends are projected to continue for a number of decades.

Chronic glucose-lowering effects of rosiglitazone and bis(ethylmaltolato)oxovanadium(IV) in ZDF rats

The aim of this study was to determine if there was a synergistic or additive effect of a thiazolidinedione derivative (rosiglitazone (ROS)) and a vanadium compound (bis(ethylmaltolato)oxovanadium(IV) (BEOV)) on plasma glucose and insulin levels following chronic oral administration to Zucker diabetic fatty (ZDF) rats. Whole-blood vanadium levels were determined at time 0 and at days 1, 6, and 18. The doses of BEOV (0.1 mmol/kg) and ROS (2.8 µmol/kg) were selected to produce a glucose-lowering effect in 30% (ED30) of animals. Both drugs were administered daily by oral gavage as suspensions in 1% carboxymethylcellulose (CMC) in a volume of 2.5 mL/kg. The total volume administered to all rats was 5 mL/(kg·day). The combination of BEOV and ROS was effective in lowering plasma glucose levels to <9 mmol/L in 60% of fatty animals as compared with 30% for BEOV and 10% for ROS alone. The age-dependent decrease in plasma insulin levels associated with β-cell failure in the ZDF rats did not occur in the BEOV-treated fatty groups. There was no effect of any treatment on body weight; however, there was a significant reduction in both food and fluid intake in fatty groups treated with BEOV. There were no overt signs of toxicity and no mortality in this study. Both BEOV and ROS were effective in lowering plasma glucose levels, as stated above, and there was at least an additive effect when BEOV and ROS were used in combination.Key words: rosigitazone, bis(ethylmaltolato)oxovanadium(IV), diabetes, ZDF rats.

Parents Want to Know if Their Child Is at High Risk of Getting Diabetes

Not least among professionals, voices have been raised against screening research projects, which have been regarded as involving a risk of being unethical as they may disturb, scare, or even harm the included people without giving enough benefit. This problem with large-scale screening should be especially pronounced if increased risk of a serious disease like type 1 diabetes is identified when no effective prevention is available, and even more problematic if children were involved. ABIS (All Babies in Southeast Sweden) is a screening project including 17,000 newborn babies in the general population, followed prospectively to identify children at risk to get diabetes, and to study the influence of environmental factors causing the disease process. Four hundred randomly selected ABIS families received a questionnaire on attitudes and ethical questions regarding the project to be answered anonymously: 293/400 (73.3%) answered; 279/293 (95.3%) stated that they regarded it their right to be informed of results in the study and 278/293 (94.9%) said they really want to know. In fact, 254/293 (86.7%) report wanting to know if their child has increased risk of getting diabetes even if there is no preventive measure available. This clear result supports the view that this type of study may well be ethically justified as long as informed consent can be given based on adequate understanding and voluntariness. The results may have implications for the design of future screening studies.

Controlled trial of a multifaceted intervention for improving quality of care for rural patients with type 2 diabetes

OBJECTIVE

Despite good evidence and clinical practice guidelines, studies document that treatment of type 2 diabetes is less than optimal. Lack of resources or limited access may put patients in rural communities at particular risk for suboptimal care.

RESEARCH DESIGN AND METHODS

We conducted a prospective, before/after study with concurrent controls to assess the effectiveness of a multidisciplinary diabetes outreach service (intervention) for improving the quality of care for rural patients with type 2 diabetes. Our intervention consisted of six monthly visits by a traveling team of specialist physicians, nurses, dieticians, and a pharmacist. The core of this service was specialist-to-rural primary care physician academic group detailing. Two comparable regions in Northern Alberta were randomly allocated to control or intervention. Data were collected before and 6 months after intervention in a representative volunteer sample. The primary outcome was a 10% improvement in any one of the following: blood pressure, total cholesterol, or HbA(1c).

RESULTS

Our analysis included 200 intervention and 179 control subjects; 14 subjects were at all three primary outcome targets at baseline. The intervention was associated with a trend toward improvement in primary outcome at 6 months (44% intervention vs. 37% control; odds ratio 1.32, 95% CI 0.87-1.99). The intervention was associated with a significant improvement in blood pressure (42% intervention vs. 25% control, P = 0.004); however, there were only small, nonsignificant changes in cholesterol or HbA(1c). The intervention was associated with a significant increase in satisfaction with diabetes care. Multivariate adjustment for baseline differences between intervention and control subjects did not affect any of the main results.

CONCLUSIONS

A diabetes outreach service has the potential to improve the quality of diabetes care for rural patients. Future studies need to involve longer timelines and larger sample sizes.

Thiazolidinediones in type 2 diabetes mellitus: current clinical evidence

Type 2 diabetes mellitus is characterised by insulin resistance as well as progressive pancreatic beta cell dysfunction. The cornerstone of current oral blood-glucose lowering therapy consists of metformin, which primarily lowers hepatic glucose production, and the sulphonylureas that act by stimulating pancreatic beta-cells to secrete insulin. Recently, a novel class of agents, the thiazolidinediones, has been introduced that favourably influence insulin sensitivity and possibly also pancreatic beta-cell function. The thiazolidinediones are synthetic ligands that bind to the nuclear peroxisome proliferator-activated receptor-gamma and exert their action by activating transcription of genes that, among others, regulate adipocyte differentiation and adipogenesis as well as glucose and lipid metabolism. To date, the precise mechanisms underlying the actions of thiazolidinediones are largely unknown. When given as monotherapy or in combination with sulphonylureas, metformin or insulin in patients with type 2 diabetes, the currently available thiazolidinediones (rosiglitazone and pioglitazone) ameliorate glycaemic control, by lowering fasting and postprandial blood glucose levels, and improve insulin sensitivity in placebo-controlled trials. They seem to have differential effects on dyslipidaemia in patients with type 2 diabetes; rosiglitazone increases total cholesterol as well as high-density lipoprotein (HDL) and low-density lipoprotein cholesterol levels and affects plasma triglyceride levels depending on the baseline values, whereas pioglitazone lowers triglycerides and increases HDL cholesterol levels. The adverse events of both agents that occur with greater frequency than in patients treated with placebo are fluid retention and oedema. As demonstrated, mainly in preclinical studies to date, rosiglitazone and pioglitazone possess beneficial effects on other cardiovascular risk factors associated with the insulin resistance syndrome. Thus, these agents were shown to decrease blood pressure, enhance myocardial function and fibrinolysis, as well as possess anti-inflammatory and other beneficial vascular effects. Long-term efficacy and surveillance of this promising class of drugs in patients, however, still need to be demonstrated in outcome trials.

The prevalence and management of diabetes in Thai adults: the international collaborative study of cardiovascular disease in Asia

OBJECTIVE

The aim of this study was to determine in Thai adults aged >or=35 years the prevalence and management of diabetes and the associations of diabetes with cardiovascular risk factors.

RESEARCH DESIGN AND METHODS

The International Collaborative Study of Cardiovascular Disease in Asia was a complex sample survey. Data from a structured questionnaire, brief physical examination, and blood sample were collected from 5,105 individuals aged >or=35 years (response rate 68%). Population estimates were calculated by applying sampling weights derived from the 2000 Thai census.

RESULTS

The estimated national prevalence of diabetes in Thai adults was 9.6% (2.4 million people), which included 4.8% previously diagnosed and 4.8% newly diagnosed. The prevalence of impaired fasting glucose was 5.4% (1.4 million people). Diagnosed diabetes, undiagnosed diabetes, and impaired fasting glucose were associated with greater age, BMI, waist-to-hip ratio, systolic blood pressure, total cholesterol, and serum creatinine levels. The majority of individuals with diagnosed diabetes had received dietary or other behavioral advice, and 82% were taking oral hypoglycemic therapy. Blood pressure-lowering therapy was provided to 67% of diagnosed diabetic patients with concomitant hypertension.

CONCLUSIONS

Diabetes is common in Thailand, but one-half of all cases are undiagnosed. Because diagnosed diabetes is likely to be treated with proven, low-cost, preventive therapies such as glucose lowering and blood pressure lowering, initiatives that increased diagnosis rates would be expected to produce substantial health benefits in Thailand.

Is glycosylated hemoglobin A1c a surrogate for metabolic syndrome in nondiabetic, first-degree relatives of African-American patients with type 2 diabetes?

Glycosylated hemoglobin (Hb)A1c provides a practical assessment of long-term glycemic control in patients with diabetes. However, whether HbA1c has any clinical significance in metabolic syndrome (MS) in nondiabetic subjects remains debatable. Therefore, we examined the impact of different levels of HbA1c on insulin sensitivity (Si), non-insulin-dependent glucose disposal, and blood pressure (BP), as well as lipids and lipoproteins in nondiabetic, first-degree relatives of African-American patients with type 2 diabetes. The study consisted of 219 nondiabetic, first-degree relatives (offspring and siblings) of African-American patients with type 2 diabetes. To examine the metabolic impact of HbA1c in our population, HbA1c was divided into tertiles (normal range, 3.3-6.4%). The mean HbA1c was 4.7% (range, 3.3-4.8%, n = 74) for tertile 1, 5.4% (range, 4.9-5.6%, n = 73) for tertile 2, and 5.8% (range, 5.7-6.4%, n = 72) for tertile 3. Si and glucose effectiveness (Sg) were determined by the Bergman's minimal model method. Homeostasis model assessment (HOMA)-insulin resistance and HOMA-beta-cell function were also estimated. BP, body compositional variables, and body fat distribution, as well as fasting serum lipid and lipoprotein concentrations, were determined in each subject. The mean age, body weight, body mass index, waist and hip circumference, and systolic and diastolic BPs were significantly (P < 0.02-0.001) greater in the subjects in tertile 3 than those in tertiles 1 and 2. The mean fasting serum glucose was significantly (P < 0.01) higher in tertile 3 (95.5 +/- 3.2 mg/dl) than in tertile 2 (83.0 +/- 2.7 mg/dl) and tertile 1 (78.8 +/- 1.5 mg/dl). Mean fasting serum insulin and c-peptide levels tended to be higher in tertile 3 subjects than in those in tertiles 1 and 2, but the mean differences did not reach statistical significance. The mean Si was significantly (P < 0.001) lower in the subjects in tertile 3 [1.66 +/- 0.2019 x 10(-4).min(-1)( micro U/ml)(-1)], when compared with those in tertile 1 [2.27 +/- 0.20 19 x 10(-4).min(-1)( micro U/ml)(-1)] and tertile 2 [2.61 +/- 0.19 x 10(-4).min(-1)( micro U/ml)(-1)]. The mean Sg was significantly (P < 0.02) lower in tertile 3 (1.95 +/- 0.12 x 10(-2).min(-1)), when compared with those of tertile 1 (2.27 +/- 0.10 x 10(-2).min(-1)) and tertile 2 (2.29 +/- 0.11 x 10(-2).min(-1)). In addition, the (HOMA)-insulin resistance was significantly (P < 0.01) higher in tertile 3 (3.62 +/- 0.26) than in tertile 1 (2.6 +/- 0.21) and tertile 2 (2.55 +/- 0.31) HbA1c. In contrast, HOMA-beta-cell function, was not different among tertiles 1, 2, and 3. Mean fasting serum triglycerides, cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol levels also were not significantly different in subjects in tertile 3, when compared with those in tertiles 1 and 2. In summary, the present study demonstrates that the upper tertile HbA1c level (tertile 3) reflects some components of MS in the nondiabetic, obese, first-degree relatives of African-Americans who are genetically predisposed to type 2 diabetes. The metabolic abnormalities in the upper tertile 3 subjects included a reduced insulin action (Si) and reduced Sg, as well as elevated systolic and diastolic BPs, but not beta-cell secretion and lipids and lipoproteins. We conclude that the upper tertile of HbA1c should be considered as a major surrogate of MS in high-risk African-Americans who are genetically predisposed to type 2 diabetes.

Secondary prevention of cardiovascular events with long-term pravastatin in patients with diabetes or impaired fasting glucose: results from the LIPID trial

OBJECTIVE

Diabetes, a major health problem worldwide, increases the risk of cardiovascular disease and its associated mortality: The Long-Term Intervention with Pravastatin in Ischemic Disease (LIPID) trial showed that cholesterol-lowering treatment with pravastatin reduced mortality and coronary heart disease (CHD) events in 9014 patients aged 31-75 years with CHD and total cholesterol 4.0-7.0 mmol/l. We measured the effects of pravastatin therapy, 40 mg/day over 6.0 years, on the risk of CHD death or nonfatal myocardial infarction and other cardiovascular outcomes in 1,077 LIPID patients with diabetes and 940 patients with impaired fasting glucose (IFG).

RESULTS

In patients allocated to placebo, the risk of a major CHD event was 61% higher in patients with diabetes and 23% higher in the IFG group than in patients with normal fasting glucose, and the risk of any cardiovascular event was 37% higher in the diabetic group and 19% higher in the IFG group. Pravastatin therapy reduced the risk of a major CHD event overall from 15.9 to 12.3% (relative risk reduction [RRR] 24%, P < 0.001) and from 23.4 to 19.6% in the diabetic group (19%, P = 0.11); in the diabetic group, the reduction was not significantly different from the reductions in the other groups. Pravastatin reduced the risk of any cardiovascular event from 52.7 to 45.2% (21%, P < 0.008) in patients with diabetes and from 45.7 to 37.1% (26%, P = 0.003) in the IFG group. Pravastatin reduced the risk of stroke from 9.9 to 6.3% in the diabetic group (RRR 39%, CI 7-61%, P = 0.02) and from 5.4 to 3.4% in the IFG group (RRR 42%, CI -9 to 69%, P = 0.09). Pravastatin did not reduce the incidence of diabetes. Over 6 years, pravastatin therapy prevented one major CHD event (CHD death or nonfatal myocardial infarction) in 23 patients with IFG and 18 patients with diabetes. A meta-analysis of other major trials confirmed the high absolute risks of diabetes and IFG and the absolute benefits of statin therapy in these patients.

CONCLUSIONS

Cholesterol-lowering treatment with pravastatin therapy prevents cardiovascular events, including stroke, in patients with diabetes or IFG and established CHD.

Roles of 5'-AMP-activated protein kinase (AMPK) in mammalian glucose homoeostasis

AMPK (5'-AMP-activated protein kinase) is emerging as a metabolic master switch, by which cells in both mammals and lower organisms sense and decode changes in energy status. Changes in AMPK activity have been shown to regulate glucose transport in muscle and glucose production by the liver. Moreover, AMPK appears to be a key regulator of at least one transcription factor linked to a monogenic form of diabetes mellitus. As a result, considerable efforts are now under way to explore the usefulness of AMPK as a therapeutic target for other forms of this disease. Here we review this topic, and discuss new findings which suggest that AMPK may play roles in regulating insulin release and the survival of pancreatic islet beta-cells, and nutrient sensing by the brain.

Global policy: aspects of diabetes in India

Diabetes has already been described as an epidemic, but predictions for future increases in prevalence, especially in developing countries, point to a major healthcare crisis for the future. Very little is known about the economic impact of diabetes in the developing world where predicted increases in prevalence are greatest. This paper discusses the implications of a recent study of the economic aspects of diabetes in India. The study aims were to estimate the costs of diabetes care and to assess the awareness of patients and healthcare professionals about the prevention and treatment of diabetes. The findings confirm reports from earlier studies of the high costs of treatment amongst all socio-economic patient groups resulting in a serious burden on both patients and state resources alike. Both patients and medical practitioners displayed a lack of comprehension of the need for constant disease monitoring and consistent approaches to tight glycaemic control. The long term economic implications are worrying. With the Indian diabetic population predicted to rise to >80.9 million by the year 2030, immediate health policy restructuring and investment will be needed if the best use is to be made of the scarce healthcare resources.

Quality of care for patients with Type 2 diabetes mellitus--a long-term comparison of two quality improvement programmes in the Netherlands

AIM

To compare two intervention programmes, aimed at improving the quality of care provided for patients with Type 2 diabetes in the longer term.

METHODS

A retrospective comparison of data derived from two non-randomized trials with 3.5 years of follow-up. In the first intervention group 401 patients were included, 413 in the second intervention group and 105 in the reference group. The first programme focused on improving the skills and knowledge of general practitioners (GPs) with regard to Type 2 diabetes, and supported them in making organizational changes in their practice (GP care only). Centralized shared diabetes care was implemented in the second programme in which the GPs received therapy advice according to a protocol for each individual patient. The patients were also encouraged in self-management, and received structured diabetes education (Diabetes Service). The main patient outcomes were HbA1c, blood pressure and serum lipid levels. Multilevel analysis was applied to adjust for dependency between repeated observations within one patient and for clustering of patients within general practices.

RESULTS

The HbA1c levels of patients of GPs who were supported by the Diabetes Service improved significantly more than the HbA1c levels of patients receiving GP care only (-0.28% [95% confidence interval (CI) -0.45; -0.11]). In contrast, the systolic blood pressure of patients receiving GP care only decreased more than that of patients of GPs supported by the Diabetes Service [4.14 mmHg (95% CI 1.77, 6.51)].

CONCLUSION

A Diabetes Service, providing GPs with individual therapy advice and patient education, resulted in better glycaemic control over 3.5 years than an intervention aimed at improving the skills of GPs in combination with organizational changes in the general practice.

Candidate gene association study in type 2 diabetes indicates a role for genes involved in beta-cell function as well as insulin action

Type 2 diabetes is an increasingly common, serious metabolic disorder with a substantial inherited component. It is characterised by defects in both insulin secretion and action. Progress in identification of specific genetic variants predisposing to the disease has been limited. To complement ongoing positional cloning efforts, we have undertaken a large-scale candidate gene association study. We examined 152 SNPs in 71 candidate genes for association with diabetes status and related phenotypes in 2,134 Caucasians in a case-control study and an independent quantitative trait (QT) cohort in the United Kingdom. Polymorphisms in five of 15 genes (33%) encoding molecules known to primarily influence pancreatic beta-cell function-ABCC8 (sulphonylurea receptor), KCNJ11 (KIR6.2), SLC2A2 (GLUT2), HNF4A (HNF4alpha), and INS (insulin)-significantly altered disease risk, and in three genes, the risk allele, haplotype, or both had a biologically consistent effect on a relevant physiological trait in the QT study. We examined 35 genes predicted to have their major influence on insulin action, and three (9%)-INSR, PIK3R1, and SOS1-showed significant associations with diabetes. These results confirm the genetic complexity of Type 2 diabetes and provide evidence that common variants in genes influencing pancreatic beta-cell function may make a significant contribution to the inherited component of this disease. This study additionally demonstrates that the systematic examination of panels of biological candidate genes in large, well-characterised populations can be an effective complement to positional cloning approaches. The absence of large single-gene effects and the detection of multiple small effects accentuate the need for the study of larger populations in order to reliably identify the size of effect we now expect for complex diseases.

Metabolic Syndrome: epidemiology and more extensive phenotypic description. Cross-sectional data from the Bruneck Study

OBJECTIVES

The present study aimed at evaluating the prevalence of the Metabolic Syndrome and at identifying its additional clinical features.

RESEARCH DESIGN AND METHODS

Within a prospective population-based survey examining 888 subjects aged 40-79 y, subjects were identified fulfilling the WHO and the National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATPIII) criteria for diagnosing the Metabolic Syndrome. In these subjects and in the rest of the sample (controls), several metabolic and nonmetabolic biochemical parameters were compared.

RESULTS

The prevalence of the Metabolic Syndrome by WHO criteria was 34.1% (95% CI 31.0-37.2) and by NCEP-ATPIII criteria 17.8% (15.5-20.3). The prevalence was significantly higher in older subjects and in those less physically active. Subjects with the Metabolic Syndrome either by WHO or by NCEP-ATPIII criteria showed higher levels of oxidized low-density lipoprotein, apolipoprotein B, urate, leptin, fibrinogen, leukocytes, erythrocyte sedimentation rate, GOT, gamma-GT and soluble endothelial adhesion molecules (E-selectin, vascular adhesion molecule-1 and intercellular adhesion molecule-1) and lower apolipoprotein A concentrations. Insulin resistance, as assessed by the Homeostasis Model Assessment, increased with the increase in the number of traits composing the syndrome found within the single individual. Subjects with insulin resistance had more pronounced abnormalities in several parameters, including the additional features of the syndrome (eg fibrinogen and soluble adhesion molecules).

CONCLUSIONS

The Metabolic Syndrome occurs very frequently in the general population aged 40-79 y, and is associated with several additional metabolic and nonmetabolic abnormalities that likely contribute to an increased cardiovascular risk. Insulin resistance seems to play a major role in classic and additional abnormalities featuring the Metabolic Syndrome.

Is there a role for alpha-glucosidase inhibitors in the prevention of type 2 diabetes mellitus?

Type 2 diabetes mellitus is a major health problem associated with excess morbidity and mortality. As the prevalence of this metabolic disorder is rapidly increasing and current treatment fails to stabilise the disease in most patients, prevention should be considered as a key objective in the near future. People who develop type 2 diabetes pass through a phase of impaired glucose tolerance (IGT). Defects in the action and/or secretion of insulin are the two major abnormalities leading to development of glucose intolerance. Any intervention in the impaired glucose tolerance phase that reduces resistance to insulin or protects the beta-cells, or both, should prevent or delay progression to diabetes.Acarbose, miglitol and voglibose act by competitively inhibiting the alpha-glucosidases, a group of key intestinal enzymes involved in the digestion of carbohydrates. They decrease both postprandial hyperglycaemia and hyperinsulinaemia, and thereby may improve sensitivity to insulin and release the stress on beta-cells. These compounds do not induce hypoglycaemia and have a good safety profile, although gastrointestinal adverse effects may limit long-term compliance to therapy. The recent placebo-controlled prospective STOP-noninsulin-dependent diabetes mellitus (STOP-NIDDM) trial demonstrated that acarbose 100mg three times daily reduces the risk of developing type 2 diabetes in patients with IGT (relative risk reduction of 25% after a mean follow-up of 3.3 years). The 6-year Early Diabetes Intervention Trial (EDIT), comparing the effect of acarbose 50mg three times daily to that of metformin, showed a trend to a positive effect of acarbose compared with placebo, in a mid-term 3-year analysis, which should be confirmed in the final analysis. To our knowledge, no such prevention intervention trials have been or are currently being performed with miglitol or voglibose. In conclusion, because of its absence of toxicity and its particular mechanism of action on gastrointestinal tract and indirect consequences on both insulin action and beta-cell function, acarbose may be used to prevent type 2 diabetes. If the ongoing EDIT trial confirms the positive results of the recent STOP-NIDDM trial, acarbose could be used, either as an alternative or in addition to changes in lifestyle, to delay development of diabetes in patients with IGT. However, the best dosage of acarbose for this specific indication remains to be specified, especially when all three important parameters, efficacy, tolerance and cost, are taken into consideration.

The receptor RAGE as a progression factor amplifying arachidonate-dependent inflammatory and proteolytic response in human atherosclerotic plaques: role of glycemic control

BACKGROUND

RAGE (receptor for advanced glycation end products [AGEs]) plays a role in diabetic atherosclerosis. Recently, we have demonstrated enhanced expression of cyclooxygenase-2 and PGE synthase-1 (COX-2/mPGES-1) in human symptomatic plaques, and provided evidence that it is associated with metalloproteinase (MMP)-induced plaque rupture. However, the specific transmembrane signaling pathway(s) influencing plaque COX-2/mPGES-1 expression is unknown. The aim of this study was to characterize RAGE expression in human plaques and to correlate it with the inflammatory infiltration, COX-2/mPGES-1 and MMP expression, and with clinical evidence of diabetes.

METHODS AND RESULTS

Plaques obtained from 60 patients undergoing carotid endarterectomy were divided into diabetic and nondiabetic according to clinical evidence of type 2 diabetes. Plaques were subjected to analysis of RAGE, NF-kappaB, COX-2/mPGES-1, MMP-2 and MMP-9, lipid and oxidized LDL (oxLDL) content, and collagen content by immunohistochemistry and Western blot, whereas zymography was used to detect MMP activity. Immunohistochemistry was used to identify CD68+ macrophages, CD3+ T-lymphocytes, smooth muscle cells (SMCs), and HLA-DR+ inflammatory cells. Diabetic plaques had more (P<0.0001) macrophages, T-lymphocytes, and HLA-DR+ cells, more (P<0.0001) immunoreactivity for RAGE, activated NF-kappaB, COX-2/mPGES-1, and MMPs, increased (P<0.0001) gelatinolytic activity, reduced (P<0.0001) collagen content, and increased (P<0.0001) lipid and oxLDL content. Interestingly, RAGE, COX-2/mPGES-1, and MMP expression was linearly correlated with plasma level of HbA1c.

CONCLUSIONS

In conclusion, this study demonstrates in humans that RAGE overexpression is associated with enhanced inflammatory reaction and COX-2/mPGES-1 expression in diabetic plaque macrophages, and this effect may contribute to plaque destabilization by inducing culprit metalloproteinase expression.

Altered functional coupling of coronary K+ channels in diabetic dyslipidemic pigs is prevented by exercise

Chronic hyperglycemia and hypercholesterolemia have been shown to alter ionic currents in vascular smooth muscle. We tested the hypothesis that the combined effect of hyperglycemia and hyperlipidemia (diabetic dyslipidemia) would increase the Ca2+-sensitive K+ (KCa) current as a compensatory response to an increase in intracellular Ca2+ concentration. We also hypothesized that exercise training would prevent this elevation in KCa current. Miniature Yucatan swine were randomly assigned to five groups: control, standard pig chow (C, n = 6); hyperlipidemic, high-fat pig chow (H, n = 5); diabetic, standard pig chow (D, n = 7); diabetic, high-fat pig chow ("diabetic dyslipidemic," DD, n = 12); and exercise-trained DD (DDX, n = 9). High-fat chow consisted of standard minipig chow supplemented with cholesterol (2%) and coconut oil. Increased coronary vasoconstriction assessed in vivo and in vitro in DD was prevented by exercise. Patch-clamp experiments performed on right coronary artery smooth muscle cells resulted in greater K+ current densities in the H, D, and DD groups vs. the DDX group between -10 and 40 mV. In fura 2-loaded cells, current activated by caffeine-induced Ca2+ release was greater in H, D, and DD compared with C and DDX (P < 0.05), whereas intracellular Ca2+ concentration was not different across groups. Finally, there were no differences in the KCa or Kv channel protein content between groups. These data indicate that hyperglycemia, hyperlipidemia, and diabetic dyslipidemia lead to elevated whole cell K+ current and increased functional coupling of KCa and Ca2+ release. Endurance exercise prevented increased coupling of Ca2+ release to KCa channel activation in diabetic dyslipidemia.

Diabetes mellitus in Turkish immigrants in Sweden

This study analyses the risk of self-reported diabetes mellitus among Turkish-born immigrants in Sweden. Two simple random samples were used: The Swedish National Board of Health and Welfare Immigrant Survey, and the Swedish Survey of Living Conditions, both from 1996. Totally 526 Turkish immigrants, 285 men and 241 women, were compared with 2854 Swedish controls, 1425 men and 1429 women, all in ages 27-60 years. Data were analysed by sex in an age-adjusted model, and a full model also included education, employment status, BMI and country of birth (logistic regression). Among Turkish men, age-adjusted diabetes prevalence was not higher than among Swedish men, odds ratio (OR) 1.04 (95% confidence interval (CI) 0.35-3.11). Among Turkish women, age-adjusted diabetes prevalence was higher than among Swedish women, OR 3.22 (95% CI 1.36-7.64), but when also adjusting for educational level, employment status and BMI, OR was 1.22 (95% CI 0.41-3.66). We conclude, that age-adjusted presence of known diabetes was higher among Turkish-born women than among Swedish women, but was explained by lower employment rate, lower educational status and a higher level of overweight and obesity.

The burden of type 2 diabetes: are we doing enough?

Increasing levels of obesity, arising from energy-rich diets and sedentary lifestyles, are driving a global pandemic of type 2 diabetes. The prevalence of type 2 diabetes worldwide is set to increase from its present level of 150 million, to 225 million by the end of the decade and to as many as 300 million by 2025. Shocking as they are, these figures represent only clinically diagnosed diabetes, and many more cases of diabetes remain undiagnosed and untreated. In addition, up to one-quarter of western populations have impaired glucose tolerance or the dysmetabolic syndrome, which are considered to represent pre-diabetic states. Type 2 diabetes is appearing increasingly in children and adolescents, and the frequency of diagnosis of paediatric type 2 diabetes is outstripping that of type 1 diabetes in some areas. The long-term complications associated with type 2 diabetes carries a crushing burden of morbidity and mortality, and most type 2 diabetic patients die prematurely from a cardiovascular event. Diabetic patients are more than twice as costly to manage as non-diabetic patients, due mainly to the high costs associated with management of diabetic complications. Indeed, diabetes care already accounts for about 2-7% of the total national health care budgets of western European countries. Controlling the type 2 diabetes epidemic will require changes to the structure of healthcare delivery. Well-resourced interventions will be required, with effective co-ordination between all levels of government, health care agencies, multidisciplinary health care teams, professional organisations, and patient advocacy groups. Above all, intervention is needed today.

Diabetes and heart disease an evidence-driven guide to risk factors management in diabetes

Type 2 diabetes is a worldwide epidemic. Cardiovascular diseases remain the major cause of death in patients with diabetes, partly because of the association of diabetes and the metabolic syndrome. In this review, we will discuss the evidence for treatment and prevention of cardiovascular diseases in patients with diabetes. Aggressive treatment of hypertension and dyslipidemia is at the cornerstone in the management of heart disease in those patients. Despite its known benefit on the prevention of the microvascular complications of diabetes, intensive glycemic control may or may not have a significant effect on reducing macrovascular diseases. Finally, lifestyle changes and other cardiovascular therapies aimed at preventing heart disease may also prevent or delay the development of diabetes.

Health care use by diabetic patients in the Netherlands: patterns and predicting factors

AIMS

Diabetic patients require care from a variety of health care providers, but little is known about their actual use of health care. Aims of this study were to (1) obtain information on health care use by diabetic patients in the Netherlands, (2) distinguish patterns of health care utilisation among these patients, and (3) develop insight into the factors predicting these patterns.

METHOD

Data on 388 diabetic patients were extracted from a nationally representative database of patients with chronic disease. Data on health care utilisation and background variables were collected in 1998 by means of a survey. Patients' GPs registered information about medical diagnosis, illness duration and co-morbidity. Analysis included descriptive statistics, as well as cluster and logistic analysis.

RESULTS

Diabetic patients use a wide range of services, but large differences exist. Four patterns of health care utilisation could be distinguished: a pattern of low consumption, one of moderate consumption with a central role for internal medicine, one of more extensive diabetes care consumption, and one of high medical and home care consumption. Type 1 diabetes appeared to be an important determinant of the moderate, mainly internal medicine pattern and the more extensive diabetes care pattern. The pattern of high medical and home care was not predicted by diabetes type, but by the presence of co-morbidity and by poor self-rated health.

CONCLUSION

Despite the fact that diabetic patients use a wide range of health care services, there seems to be a problem of under utilisation, especially among type 2 diabetic patients.

Preventing Type 2 diabetes and the dysmetabolic syndrome in the real world: a realistic view

The last two decades have seen an explosive increase in the number of people with diabetes globally. There is now an urgent need for strategies to prevent the emerging global epidemic. Several recent successful intervention studies, both lifestyle and pharmacological, targeting subjects with impaired glucose tolerance (IGT) have stimulated enthusiasm for prevention of Type 2 diabetes. Lifestyle interventions reduced the incidence of diabetes by over 50% in the Finnish Diabetes Prevention Study and the Diabetes Prevention Program. Can the findings of these two studies be applied globally? Underpinning the enthusiasm, there needs to be a realistic approach to interventions in both developed and developing nations, and in ethnic groups where a better understanding of the socio-economic, cultural and demographic issues and perceptions surrounding chronic diseases such as diabetes is required. Whether the strategies used in these two studies can be translated into a 'real world' scenario is doubtful. In practice, it is more than likely that a number of strategies will be needed to compliment the lifestyle approach. These will include pharmacological approaches with metformin, acarbose and other agents used to treat diabetes and its complications, currently under investigation. Longer-term follow-up studies will also clarify whether both lifestyle and pharmacological interventions actually prevent Type 2 diabetes, or merely delay its onset.

Prevalence of diabetes and impaired fasting glucose in the Chinese adult population: International Collaborative Study of Cardiovascular Disease in Asia (InterASIA)

AIMS/HYPOTHESIS

To estimate the prevalence of diagnosed and undiagnosed diabetes and impaired fasting glucose in the general adult population of China.

METHODS

The International Collaborative Study of Cardiovascular Disease in ASIA, conducted from 2000 to 2001, included a nationally representative sample of 15 540 adults, aged 35 to 74 years. An overnight fasting blood specimen was collected to measure serum glucose and information on history of diabetes and use of hypoglycaemic medications was obtained by a standard questionnaire. Undiagnosed diabetes (fasting glucose > or =7.0 mmol/l) and impaired fasting glucose (6.1-6.9 mmol/l) were defined using the American Diabetes Association criteria.

RESULTS

Prevalence of self-reported diagnosed diabetes, undiagnosed diabetes, and impaired fasting glucose in Chinese adults were 1.3%, 4.2%, and 7.3%, respectively. Overall, 5.2% or 12.7 million men and 5.8% or 13.3 million women in China aged 35 to 74 years had diabetes (self-reported diagnosis plus undiagnosed diabetes). The age-standardized prevalence of diabetes was higher in residents of northern compared to southern China (7.4% vs 5.4%, p<0.001) and in those living in urban compared to rural areas (7.8% vs 5.1%, p<0.001).

CONCLUSIONS/INTERPRETATION

Our results show that the prevalence of diabetes in the adult population in China is much higher than previously reported. Three out of every four diabetes patients are undiagnosed, indicative of a lack of population-based screening programmmes and a relatively rapid and recent increase in incidence of diabetes. These results indicate that diabetes has become a major public health problem in China and underscore the need for national strategies aimed at prevention and treatment of diabetes.

The potential of metformin for diabetes prevention

Well designed intervention trials, such as the Diabetes Prevention Program (DPP), have demonstrated the potential of lifestyle interventions or pharmacologic treatments for the prevention or delay of type 2 diabetes in subjects with impaired glucose tolerance (IGT). Lifestyle interventions are likely to form the cornerstone of the management of IGT in the future, as they do in the management of type 2 diabetes today. However, it remains to be seen whether the intensive lifestyle interventions employed in trials such as the DPP can be transferred successfully from the highly structured environment of a randomised trial to routine, day-to-day management within the primary care sector. Thus, pharmacologic treatment may provide an important additional option where subjects are unwilling or unable to improve their diet and levels of physical activity. Treatment with metformin significantly reduced the incidence of diabetes in subjects with IGT and high-normal fasting plasma glucose in the DPP. Moreover, metformin was well tolerated, and health economic analyses suggest that metformin treatment is cost-effective in the US and Europe. The DPP investigators found that the protective effect of metformin persisted beyond the end of the study, and estimated that only one quarter of the protection arose from a short-lived pharmacological effect. The results of the DPP identify metformin as an effective option for the prevention of diabetes in subjects with IGT and impaired fasting glucose.

Efficacy of acarbose in Chinese subjects with impaired glucose tolerance

This multicentre, double-blind, placebo-controlled study investigated the efficacy of acarbose in Chinese individuals with impaired glucose tolerance (determined using a 75 g oral glucose tolerance test). Subjects were randomised to either placebo or acarbose 50 mg t.i.d. for a period of 16 weeks. Primary efficacy variables were the maximum postprandial plasma glucose value (C(max)) and the serum insulin profile. Secondary efficacy parameters included postprandial glucose profile, maximum postprandial insulin concentration (C(max)), changes in lipid profile and blood pressure and HbA(1c) and body weight and conversion to Type 2 diabetes. In the intention-to-treat analysis, acarbose treatment resulted in significantly higher reductions in postprandial glucose and serum insulin concentrations compared to placebo. Triglyceride concentration was the only lipid parameter to be significantly reduced in acarbose subjects. Loss of body weight was also significantly greater for acarbose than placebo subjects. Some 19 individuals converted to Type 2 diabetes (seven acarbose, 12 placebo), but this difference was not significant. Acarbose is efficacious in improving the metabolic state of individuals with impaired glucose tolerance indicating a potential benefit for the delay or prevention of onset of Type 2 diabetes in Chinese subjects.