Intensive blood-glucose control with sulphonylureas or insulin compared with conventional treatment and risk of complications in patients with type 2 diabetes (UKPDS 33). UK Prospective Diabetes Study (UKPDS) Group

Glycemic control and cardiovascular disease in type 2 diabetes: a review

Cardiovascular disease is the major cause of morbidity and mortality in people with Type 2 diabetes, and risk of atherosclerotic disease is markedly increased in people with diabetes compared to people with normal glucose tolerance. The excess risk can not be completely explained by increased prevalence of other cardiovascular disease risk factors such as hypertension and hyperlipidaemia in people with diabetes. This review examines the role of hyperglycemia and glycemic control in cardiovascular disease in people with Type 2 diabetes. The results of prospective observational studies and randomized controlled trials are summarized. We conclude that control of hypertension and hyperlipidemia are important to reduce risk of cardiovascular disease in people with diabetes and may be more easily achieved than tight glycemic control.

Attending the diabetes center is associated with reduced cardiovascular mortality in type 2 diabetic patients: the Verona Diabetes Study

BACKGROUND

The aim of the present study was to compare specific causes of death in Type 2 diabetic patients attending and not attending the diabetes center.

METHODS

The study was carried out within the framework of the Verona Diabetes Study, a population-based survey of known diabetes prevalence with a 10-year mortality follow-up. On 31 December 1986, 7148 Type 2 diabetic patients were identified in Verona, north-east Italy. Among them 4047 regularly attended the diabetes center, while 3101 did not attend the diabetes center. On 31 December 1996, life status was determined and the underlying cause of death was coded according to the ICD-9. During the follow-up, 2896 subjects died. Difference in mortality from specific causes between attenders and non-attenders were evaluated by a Cox model, controlling for sex, age, diabetes treatment and place of residence (downtown vs suburbs).

RESULTS

Mortality was lower in subjects who attended the diabetes center (38. 6% vs 43.0%, p<0.001). This phenomenon was mainly due to lower cardiovascular (p=0.002) and digestive (p=0.047) mortality.

CONCLUSIONS

These data support the conclusion that attending the diabetes center reduces cardiovascular and, to a lesser extent, digestive mortality.

Reducing the burden of diabetes: managing cardiovascular disease

Of the threats to health and life that beset the person with diabetes, cardiovascular disease (CVD), particularly coronary heart disease (CHD) but also cerebrovascular and peripheral vascular disease, represent the heaviest burden. The relative risk for CVD is very high for Type 1 diabetes, but the absolute risk, in terms of numbers, is much higher for Type 2. In all societies, diabetes increases cardiovascular risk twofold or more, compared with the local non-diabetic population. Some of the evidence for this diabetes-related increase in cardiovascular risk is reviewed and its relationship to recognised cardiovascular risk factors considered. The explanation of the enhanced susceptibility to atherosclerotic disease in diabetes remains a matter of contention. How much can be explained by greater prevalence in diabetes of such risk factors as hypertension and dyslipidaemia? To what extent is the impact of a given level of risk factor magnified by a co-existing diabetic state? Is the increased cardiovascular morbidity and mortality secondary to risk factors specifically related to the diabetic state itself? Does the explanation lie in altered coagulability due to changes in platelet activation and aggregability, fibrinogen levels, Factor VII, von Willebrand factor or PAI-1, in the concentration or composition of plasma lipoproteins, in defective endothelial cell function or other metabolic abnormalities of the arterial wall? To what extent is cardiovascular risk related to the degree of hyperglycaemia, protein glycation, relative hyperinsulinaemia and insulin resistance? Data from recent epidemiological, intervention and laboratory investigations bearing on causation, management and prevention of CVD in diabetes are reviewed. Evidence for the impact of correction of glycaemia, dyslipidaemia and raised arterial pressure is considered and reasons are adduced for a broad and proactive therapeutic approach with early identification and vigorous correction of key risk factors.

Treating obese patients with poorly controlled diabetes: confessions of an insulin therapist

How to treat the obese, poorly controlled patient with diabetes is a common and vexed question. Using insulin without giving thought to ameliorating the inevitable weight gain will cause desperation in the physician and despondency in the patient. Novel attempts at dietary manipulation before commencing insulin can be beneficial provided there is close scrutiny of short-term changes in weight and metabolic parameters. Combinations of insulin and metformin can also be helpful at an early stage. It may be helpful to use insulin as a therapeutic trial provided the goals of therapy are agreed with the patient at the outset. Above all it is important to avoid therapeutic nihilism - a minority of fat people may be jolly but few are truly happy.

Rosiglitazone monotherapy improves glycaemic control in patients with type 2 diabetes: a twelve-week, randomized, placebo-controlled study

AIM

Rosiglitazone is the most potent of the thiazolidinediones, a novel class of oral antidiabetic agents that reduce blood glucose levels by sensitizing peripheral tissues to insulin. This study was designed to identify doses of rosiglitazone that would lower fasting plasma glucose (FPG) in patients with type 2 diabetes.

METHODS

In this 12-week, double-blind, multicentre study, 380 patients with FPG values > or =7.8 mmol/L (140 mg/dL) and < or =13.3 mmol/L (240 mg/dL) were randomly assigned to receive treatment with placebo or rosiglitazone, 0.05, 0.25, 1.0, or 2.0 mg twice daily. The primary efficacy parameter was changed in FPG from baseline after 12 weeks of treatment. Secondary endpoints were changes in HbA1c, fructosamine, C peptide, insulin, lipid levels, and body weight (b.w.). Safety monitoring included clinical laboratory evaluations, electrocardiography, and echocardiography.

RESULTS

Rosiglitazone 1.0 and 2.0 mg b.i.d. produced significant decreases in FPG (p=0.0001). Fructosamine also decreased in patients treated with these two dosages (p=0.003 in the 2.0 mg b.i.d. group). Rosiglitazone 2.0 mg b.i.d. significantly reduced plasma insulin levels (p=0.0044) and free fatty acids (p=0.0014) compared with placebo. Total cholesterol (p=0.0001), HDL (p=0.0009), and LDL (p=0.0001) increased in the rosiglitazone 2.0 mg b.i.d. group, but there was no significant change in the total cholesterol/HDL ratio or triglyceride levels in any rosiglitazone treatment group. Clinically insignificant dose-dependent increases in b.w. were observed in the rosiglitazone 1.0 and 2.0 mg b.i.d. treatment groups.

CONCLUSIONS

Twelve weeks of treatment with rosiglitazone 2.0 mg b.i.d. significantly decreases fasting plasma glucose, fructosamine, plasma insulin, and free fatty acids in patients with type 2 diabetes. Longer studies using higher doses will be needed to assess the efficacy and safety of rosiglitazone in patients with type 2 diabetes mellitus.

Type 2 diabetes towards the new millennium--the relative importance of glycaemic versus lipid control

The prevalence of type 2 diabetes is set to increase. The UKPDS has shown that better average glycaemic control over time leads to a reduction in microvascular complications. Macrovascular outcomes are also reduced in overweight subjects treated with metformin. The UKPDS and our own data, however, show that the natural history of type 2 diabetes is one of progressive deterioration in glycaemic control despite treatment. Lipid parameters emerges as the strongest predictors of outcomes in type 2 diabetes and suggest where therapeutic endeavours might best be directed. Ongoing trials of lipid-modifying therapies in type 2 diabetes will help to substantiate this. In the meantime, efforts to improve glycaemic control should not be pursued to the exclusion of other abnormalities that may have a greater relevance to outcomes of type 2 diabetes. There is an urgent need for better prevention and intervention strategies as we approach the new millennium.

Is 'routine' laboratory testing a thing of the past? Current recommendations regarding screening

A 55-year-old man comes to you for a routine physical examination. He is a nonsmoker who takes no medications and has no signs of acute or chronic disease, and he has not seen a doctor in years. What blood work should you order for this patient? The authors of this article help you answer this question in light of recent advances in technology, restrictions in healthcare reimbursement, and increased sophistication in cost-benefit analysis for laboratory testing.

Polyneuropathy in Australian outpatients with type II diabetes mellitus

In order to determine the local prevalence of polyneuropathy among adult outpatients with type II (non-insulin-dependent) diabetes mellitus, we applied a series of standardised measures to patients attending a multidisciplinary diabetes clinic. The study group comprised 94 men and 15 women; mean age, 70.6+/-7.8 years; mean duration of diabetes, 11.7+/-10.1 years; and mean HbA1c 8.3%+/-1.7%. Neuropathy Symptom Scores > or = 1 were present in 97% of patients (mean, 3+/-2; range, 0-12), and 95% had Neuropathy Disability Scores > or = 2 (mean, 27+/-19; range, 0-87). 52% of men reported impotence. Autonomic dysfunction on cardiovascular reflex testing was present in 46% of patients (39/84). Finger and toe vibration perception thresholds were greater than 3SD higher than mean thresholds measured in control subjects without diabetes in 43% and 58% of patients, respectively. Polyneuropathy, defined as lower limb sensory and motor nerve conduction velocity or latency outside mean +/-2 SD of that measured in age-matched controls, was present in 49% of patients (53/109). These results suggest that there is a high prevalence of polyneuropathy in Australian out-patients with type II diabetes mellitus. In this study, clinical assessment using Neuropathy Disability Scores was not diagnostically useful since only five patients had a normal score. Using nerve-conduction studies as the "gold standard" diagnostic criteria, the best alternative test for the presence of polyneuropathy was toe vibration perception threshold (sensitivity 74%, specificity 56%). In view of the emerging evidence that intensive glycaemic control reduces the rate of progression of polyneuropathy, we recommend that patients with type II diabetes mellitus have nerve-conduction studies performed for early detection of this important complication.

Treatment of diabetic retinopathy

Diabetic retinopathy is a major public health problem and it remains the leading cause of blindness in people of working age (20 to 65 years). Several important clinical trials have given us the evidence base to provide clinical practice guidelines for management of this disease. With full implementation of existing technology, it should be possible to greatly improve visual outcomes for people with diabetes. There are two keys to maintaining vision in people with diabetes. First, achieving good long-term metabolic control of diabetes will limit the development and progression of diabetic retinopathy. Second, ensuring early detection of diabetic retinopathy by regular (two-yearly at least) screening examinations will allow timely referral for application of retinal photocoagulation. This paper will review the ophthalmologist's treatment of diabetic retinopathy with emphasis on the role of photocoagulation.

New OTC drugs and devices 1998: a selective review

OBJECTIVE

To create a heightened awareness of the marketing strategy of dual labeling, i.e., labeling of two benefits on a nonprescription drug product, and to review a selection of new self-care products that became available in 1998 for consumer use in the United States.

DATA SOURCES

Recent clinical and pharmaceutical industry literature.

DATA SYNTHESIS

It is critical for the pharmacist to be aware of the use of dual labeling and to be able to appropriately counsel and direct patients on how to read and understand dual labeling. In addition, numerous nonprescription products, including home diagnostic products and accessories, will continue to become available on the U.S. market. It is important that the pharmacist become as knowledgeable as possible about these, and be well positioned to educate patients about their appropriate use.

CONCLUSION

The new products cited in this review represent valuable new additions to the self-care product pool.

Intensified multifactorial intervention in patients with type 2 diabetes mellitus and microalbuminuria: the Steno type 2 randomised study

BACKGROUND

In type 2 diabetes mellitus the aetiology of long-term complications is multifactorial. We carried out a randomised trial of stepwise intensive treatment or standard treatment of risk factors in patients with microalbuminuria.

METHODS

In this open, parallel trial patients were allocated standard treatment (n=80) or intensive treatment (n=80). Standard treatment followed Danish guidelines. Intensive treatment was a stepwise implementation of behaviour modification, pharmacological therapy targeting hyperglycaemia, hypertension, dyslipidaemia, and microalbuminuria. The primary endpoint was the development of nephropathy (median albumin excretion rate >300 mg per 24 h in at least one of the two-yearly examinations). Secondary endpoints were the incidence or progression of diabetic retinopathy and neuropathy.

FINDINGS

The mean age was 55.1 years (SD 7.2) and patients were followed up for 3.8 years (0.3). Patients in the intensive group had significantly lower rates of progression to nephropathy (odds ratio 0.27 [95% CI 0-10-0.75]), progression of retinopathy (0.45 [0.21-0.95]), and progression of autonomic neuropathy (0.32 [0.12-0.78]) than those in the standard group.

INTERPRETATION

Intensified multifactorial intervention in patients with type 2 diabetes and microalbuminuria slows progression to nephropathy, and progression of retinopathy and autonomic neuropathy. However, further studies are needed to establish the effect of intensified multifactorial treatment on macrovascular complications and mortality.

Diabetes and the heart

Diabetes mellitus adversely affects the pathology, presentation and outcome of patients with coronary artery disease. Knowledge of the risks and benefits of medical and mechanical therapies particular to diabetic patients is useful in the optimal management of diabetic heart disease.

Diabetic nephropathy

Renal involvement is one of the major microvascular complications of both type 1 and type 2 diabetes mellitus. Diabetic nephropathy is the major cause of end-stage renal failure in most Western nations and is associated with increased morbidity and mortality as compared to other causes of renal disease. The pathogenesis of renal involvement in diabetes is presumed to be the result of the interplay of metabolic and hemodynamic factors. Significant advances in the prevention and treatment of progression of diabetic nephropathy have been achieved with intensive glycemic control and the treatment of elevated blood pressure. Patients with diabetes should thus be screened regularly for the appearance of any of the risk factors for renal or other complications and treated intensively according to established guidelines for control of hyperglycemia and hypertension. Ancillary therapeutic measures include treatment of hyperlipidemia, low-protein diet, and the cessation of smoking.

Continuous glucose monitoring: long-term implantable sensor approach

Problems with existing glucose monitoring technology have resulted in poor compliance with recommended monitoring guidelines by patients with diabetes. To achieve the goal of tight glucose control by patients with diabetes, a long-term implantable glucose sensor should meet the following functional requirements: it should be a one-time minimally invasive implantable with a wireless external unit; provide on-demand real-time glucose levels and trends; operate for up to 12 months after implantation with infrequent recalibration; contain built-in hypoglycemic and hyperglycemic alarms; and have an ergonomically designed, external, wearable user interface. Measurements of glucose in interstitial fluid (ISF) can be used for long-term monitoring. A novel approach to continuous and long-term glucose sensing could be based on measuring the changes in fluorescence of glucose-sensitive indicator molecules. To measure these changes in fluorescence a miniature optoelectronic device with a glucose sensitive indicator could be implanted subcutaneously for long-term remote operation. The fluorescence-based glucose sensing process is reversible and does not consume glucose. The combination of fluorescence-based glucose detection, sensor miniaturization and the use of biomaterials, inducing neovascularization at the implant site, opens the opportunity for achieving the requirements for long-term, continuous and convenient glucose monitoring.

United Kingdom prospective diabetes study (UKPDS): what now or so what?

The UKPDS was a 20-year study involving 23 centres in the United Kingdom. More than 5000 patients with Type 2 diabetes were recruited. The aim of the study was to determine the impact of intensive blood glucose control on 21 predetermined clinical endpoints using, in the care of blood glucose control, sulphonylureas or insulin therapy or, in the overweight patient, treatment with metformin. In addition, the study investigated the impact of intensive blood pressure control on macro- and microvascular complications of diabetes and compared captopril treatment with atenolol. UKPDS found that improved control of blood glucose or blood pressure reduced the risk of major diabetic eye disease by one quarter, serious deterioration of vision by nearly one half, early kidney damage by one third, strokes by one third, and death from diabetes-related causes by one third. Blood glucose control had little or no effect on macrovascular events. There was no evidence of a major detrimental effect of the drugs or insulin on survival or outcome other than the expected risk of hypoglycaemia. Metformin appeared to be the drug of choice in obese diabetic patients. The targets of glucose and blood pressure control were often achieved by using several drugs. Many patients at the end of the studies were on four or five drugs for blood glucose and blood pressure treatment. The results and implications of the study are discussed. It is proposed that the results of UKPDS herald a new era of more focused therapy of Type 2 diabetes.

Relationship between blood glucose level and mortality in type 2 diabetes mellitus: a systematic review

AIM

To review the relationship between blood glucose level and mortality in patients with Type 2 diabetes mellitus (DM) as reported in the literature.

METHODS

Literature search using Medline Search: January 1966 - April 1998.

KEYWORDS

Diabetes, Non Insulin Dependent, Mortality. Inclusion criteria for papers were: Type 2 DM; follow-up for at least 3 years; glucose or glycated haemoglobin (HbA1c) was used as parameter; published in the form of an article. Additionally all references in the selected articles that dealt with the relationship between blood glucose level and mortality in Type 2 DM were included in the search.

RESULTS

Twenty-seven eligible articles were found. Twenty-three of them showed a positive association: measures of elevated blood glucose concentrations were associated with higher mortality; in 15 out of 23 studies the positive association was statistically significant, in two only for postprandial blood glucose. One study found a nonsignificant negative relationship in a very old population.

CONCLUSION

In the literature there is a positive, but rather weak, association between the measures of blood glucose control and the risk of dying of patients with Type 2 DM. In the six larger studies (more than 100 deceased patients) that used a continuous categorization of glycaemia, the Risk ratio per unit varies from 1.03 to 1.12.

Clinical validity of a self-test fructosamine in outpatient diabetic management

BACKGROUND

Measurement of glycated hemoglobin and hemoglobin A1c (HbA1c) is now well established as the best means of measuring overall glucose control in managing diabetes. Other glycated serum protein assays reflecting recent glycemic control, e.g., glycated albumin and glycated protein (fructosamine), have also been validated in clinical studies. Regardless of the method, the expense and inconvenience of laboratory testing of blood samples may contribute to the well-documented underutilization of clinical glycated protein assessment. Accordingly, a rapid, inexpensive fingerstick test of fructosamine has been developed. This study cross-sectionally and prospectively assesses the clinical validity of fingerstick fructosamine versus laboratory determination.

METHODS

Fifty-one subjects (18 control, 33 with diabetes) participated in a cross-sectional study and 20 subjects with type 2 diabetes participated in a prospective, 6-week study with clinical intervention consisting of glipizide gits or metformin in mono- and combination therapy. Subjects had weekly laboratory determination of serum fructosamine, glycated hemoglobin, and fasting glucose; fingerstick fructosamine was obtained at each clinic visit.

RESULTS

Fingerstick fructosamine was shown to correlate highly to laboratory fructosamine (r = 0.80, p < 0.001) and glycated hemoglobin (r = 0.81, p < 0.001). In the clinical intervention study subjects, significant decreases in fasting glucose (p < 0.001), laboratory fructosamine (p < 0.001), and fingerstick fructosamine (p < 0.001) were noted compared to baseline. The subject's self-test fingerstick fructosamine mirrored laboratory testing of fructosamine in detection of changes in clinical glucose control.

CONCLUSIONS

This study demonstrates that fingerstick fructosamine correlates well to laboratory assessment of fructosamine and glycated hemoglobin. The patient self-test fructosamine provides the same clinical information as laboratory assessment.

Obesity medications and the treatment of type 2 diabetes

Obesity is a chronic disease and requires ongoing treatment. Type 2 diabetes is associated with obesity and improves with weight loss. Diets of 800 kcal/d induce twice the weight loss induced by weight loss medications. The strength of weight loss medication, which should be used with diet and a lifestyle change program, is the maintenance of weight loss. Sibutramine and orlistat are the only two medications approved for the long-term treatment of obesity. Orlistat gives a reduction of low-density lipoprotein (LDL) cholesterol in excess of that expected with weight loss, and the drop in blood pressure expected with weight loss is not seen with sibutramine. Except in newly diagnosed patients with diabetes subjects, patients with diabetes lose half the weight of subjects who do not have diabetes when treated with weight loss medications. Metformin and, to a lesser extent, acarbose cause weight loss, making them attractive choices for the treatment of obese type 2 diabetic subjects. Repaglinide appears to be weight-neutral, but other medications for patients with diabetes can be associated with weight gain. Many new medications are in development for the treatment of obesity. These new medications act through a variety of mechanisms and will surely play an increasingly important role in the treatment of obese patients with type 2 diabetes.

Issues and implications in the selection of blood glucose monitoring technologies

Over the last 2 decades assay technology originating in the laboratory has been adapted for the special situation of in vitro blood glucose monitoring in the home, at work or play, or at the bedside. The availability of blood glucose monitoring devices has had a significant impact on the treatment of diabetes, especially with respect to involving the patients in their treatment. The unique requirements of this type of testing have led to novel developments in sample acquisition techniques, analyte detection, measurement techniques, and error detection. The performance of these in vitro devices in terms of accuracy and imprecision is largely dependent on factors that contribute to variation in response that are related to testing with blood samples outside of the laboratory. These factors include, for example, variations in environmental conditions, the variability of hematocrit and oxygen concentrations of the blood, and the fact that the blood is used undiluted. Therefore, the technologies used have been selected, developed, optimized, and calibrated to minimize the impact of these factors. The technologies also must be capable of providing accurate, reproducible results over the large range of clinical interest from the hypoglycemic range to glucose concentrations 10 to 15 to 20 times greater. However, when selecting a technology there are invariably some trade-offs to consider. Thus, the products must be optimized to balance performance, reliability, and cost. Examples are discussed.

Review of management of type 2 diabetes mellitus

BACKGROUND

Commonly used drugs for type 2 diabetes are not ideal. The sulphonylureas, especially potent and long-acting agents such as glibenclamide, can induce hypoglycaemia, while metformin carries the risk of lactic acidosis.

AIM

To review the management of type 2 diabetes at the major teaching hospital in Tasmania, Australia, principally to determine the extent of use of glibenclamide and metformin in the elderly and patients where published contraindications are present.

METHODS

A retrospective review of the medical records for 150 consecutive patients with type 2 diabetes admitted to the hospital in mid-1997, was performed. An extensive range of demographic and clinical variables was recorded for each patient. These included the duration of type 2 diabetes, the presence of other medical conditions, medication history, presence of any contraindications to the use of metformin or sulphonylureas, biochemical measures of diabetic control, and the presence of any diabetic complications.

RESULTS

The mean (+/-SD) age of the 150 patients included in the study was 70.1+/-11.8 years. The mean body mass index was 28.7+/-6.2 kg/m2 and the mean recent HbA1c level was 86+/-21%; only 24.7% of patients had a HbA1c level of 7% or lower. Of the 45 patients using glibenclamide, 40 (88.9%) had one or more risk factors for hypoglycaemia: over 65 years of age, renal impairment, or cognitive impairment and living alone. The study also found an extensive use of metformin in patients with contraindications and at highest risk of developing lactic acidosis. Sixty-six out of 70 patients (94%) using metformin had at least one contraindication according to the manufacturer's prescribing information, 57% of patients had two or three contraindications and 14% of patients had more than three contraindications. More than 20% of the patients had a renal function below published exclusion criteria.

CONCLUSIONS

There was evidence of over-utilization of metformin and glibenclamide in type 2 diabetes patients most at risk of adverse reactions. Insulin therapy could be a safer and more effective management strategy in many of these patients.

Effect of intensive blood-glucose control with metformin on complications in overweight patients with type 2 diabetes (UKPDS 34). UK Prospective Diabetes Study (UKPDS) Group

BACKGROUND

In patients with type 2 diabetes, intensive blood-glucose control with insulin or sulphonylurea therapy decreases progression of microvascular disease and may also reduce the risk of heart attacks. This study investigated whether intensive glucose control with metformin has any specific advantage or disadvantage.

METHODS

Of 4075 patients recruited to UKPDS in 15 centres, 1704 overweight (>120% ideal bodyweight) patients with newly diagnosed type 2 diabetes, mean age 53 years, had raised fasting plasma glucose (FPG; 6.1-15.0 mmol/L) without hyperglycaemic symptoms after 3 months' initial diet. 753 were included in a randomised controlled trial, median duration 10.7 years, of conventional policy, primarily with diet alone (n=411) versus intensive blood-glucose control policy with metformin, aiming for FPG below 6 mmol/L (n=342). A secondary analysis compared the 342 patients allocated metformin with 951 overweight patients allocated intensive blood-glucose control with chlorpropamide (n=265), glibenclamide (n=277), or insulin (n=409). The primary outcome measures were aggregates of any diabetes-related clinical endpoint, diabetes-related death, and all-cause mortality. In a supplementary randomised controlled trial, 537 non-overweight and overweight patients, mean age 59 years, who were already on maximum sulphonylurea therapy but had raised FPG (6.1-15.0 mmol/L) were allocated continuing sulphonylurea therapy alone (n=269) or addition of metformin (n=268).

FINDINGS

Median glycated haemoglobin (HbA1c) was 7.4% in the metformin group compared with 8.0% in the conventional group. Patients allocated metformin, compared with the conventional group, had risk reductions of 32% (95% CI 13-47, p=0.002) for any diabetes-related endpoint, 42% for diabetes-related death (9-63, p=0.017), and 36% for all-cause mortality (9-55, p=0.011). Among patients allocated intensive blood-glucose control, metformin showed a greater effect than chlorpropamide, glibenclamide, or insulin for any diabetes-related endpoint (p=0.0034), all-cause mortality (p=0.021), and stroke (p=0.032). Early addition of metformin in sulphonylurea-treated patients was associated with an increased risk of diabetes-related death (96% increased risk [95% CI 2-275], p=0.039) compared with continued sulphonylurea alone. A combined analysis of the main and supplementary studies showed fewer metformin-allocated patients having diabetes-related endpoints (risk reduction 19% [2-33], p=0.033). Epidemiological assessment of the possible association of death from diabetes-related causes with the concurrent therapy of diabetes in 4416 patients did not show an increased risk in diabetes-related death in patients treated with a combination of sulphonylurea and metformin (risk reduction 5% [-33 to 32], p=0.78).

INTERPRETATION

Since intensive glucose control with metformin appears to decrease the risk of diabetes-related endpoints in overweight diabetic patients, and is associated with less weight gain and fewer hypoglycaemic attacks than are insulin and sulphonylureas, it may be the first-line pharmacological therapy of choice in these patients.