Occurrence of low blood glucose concentrations during the afternoon in type 2 (non-insulin-dependent) diabetic patients on oral hypoglycaemic agents: importance of blood glucose monitoring

Association between glycemic variability and peripheral nerve dysfunction in type 1 diabetes

INTRODUCTION

Glycemic variability (GV) may be a novel factor in the pathogenesis of diabetic complications. However, the effect of GV on peripheral nerve function has not been explored systematically.

METHODS

The relationship between GV and acute glucose levels on motor and sensory nerve function in 17 patients with type 1 diabetes mellitus (T1DM) was assessed using continuous glucose monitoring and nerve excitability techniques to provide insight into the behavior of axonal voltage-gated ion channels. The mean amplitude of glycemic excursions (MAGE) was calculated to quantify GV.

RESULTS

MAGE strongly correlated with excitability markers of altered motor and sensory axonal function, including superexcitability (r = 0.54), S2 accommodation (r = -0.76), minimum current threshold (I/V) slope (r = 0.71), strength duration time constant (r = 0.66), and latency (r = 0.65; P <  0.05). Acute glucose levels did not correlate with markers of axonal function.

CONCLUSIONS

These findings suggest that GV may be an important mediator of axonal dysfunction in T1DM and a contributing factor in development of diabetic neuropathy. Muscle Nerve, 2016 Muscle Nerve 54: 967-969, 2016.

Glycemic Variability: Assessing Glycemia Differently and the Implications for Dietary Management of Diabetes

The primary therapeutic target for diabetes management is the achievement of good glycemic control, of which glycated hemoglobin (HbA1c) remains the standard clinical marker. However, glycemic variability (GV; the amplitude, frequency, and duration of glycemic fluctuations around mean blood glucose) is an emerging target for blood glucose control. A growing body of evidence supports GV as an independent risk factor for diabetes complications. Several techniques have been developed to assess and quantify intraday and interday GV. Additionally, GV can be influenced by several nutritional factors, including carbohydrate quality, quantity; and distribution; protein intake; and fiber intake. These factors have important implications for clinical nutrition practice and for optimizing blood glucose control for diabetes management. This review discusses the available evidence for GV as a marker of glycemic control and risk factor for diabetes complications. GV quantification techniques and the influence of nutritional considerations for diabetes management are also discussed.

How can we monitor glycaemic variability in the clinical setting?

No universal consensus exists on how to express glycaemic variability. Among other parameters, standard deviation of blood glucose values, mean amplitude of glycaemic excursions (MAGE), the Low Blood Glucose Index (LBGI) and the High Blood Glucose Index (HBGI), which were subsequently combined into the Average Daily Risk Range (ADRR), mean of daily differences (MODD) and glycaemic variability index (GVI) are highlighted. The continuous glucose monitoring in research and clinical settings has been a great help for a comprehensive approach to circadian blood glucose evaluation and identification of individual patterns, mainly in type 1 diabetes, but recently also in type 2 diabetes. In everyday clinical practice the judicious use of self-monitoring of blood glucose in an educational setting involving the patient and the care team is an unreplaceable tool to effectively and safely guide behavioural and drug therapy.

Postprandial blood glucose predicts cardiovascular events and all-cause mortality in type 2 diabetes in a 14-year follow-up: lessons from the San Luigi Gonzaga Diabetes Study

OBJECTIVE

To evaluate whether postprandial blood glucose predicts cardiovascular events and all-cause mortality in type 2 diabetes in a long-term follow-up taking into account A1C and the main cardiovascular risk factors.

RESEARCH DESIGN AND METHODS

Consecutive type 2 diabetic patients (n = 505) followed up at our diabetes clinic were evaluated at baseline (1995) for the main cardiovascular risk factors and for five glycemic control parameters (fasting blood glucose, blood glucose 2 h after breakfast, blood glucose 2 h after lunch, blood glucose before dinner, and A1C); all-cause mortality and the first cardiovascular events occurring during the 14-year follow-up were measured.

RESULTS

We observed 172 cardiovascular events (34.1% of the population) and 147 deaths (29.1% of the population). Using the Cox analysis with the backward method, we categorized the variables according to the therapeutic targets of the American Diabetes Association. Our observations were as follows. When the five glycemic control parameters were considered together, the predictors were 1) for cardiovascular events, blood glucose 2 h after lunch (hazard ratio 1.507, P = 0.010) and A1C (1.792, P = 0.002); and 2) for mortality, blood glucose 2 h after lunch (1.885, P < 0.0001) and A1C (1.907, P = 0.002). When blood glucose 2 h after lunch and A1C were considered together with the main cardiovascular risk factors, the following glycemic control parameters were predictors: 1) for cardiovascular events, blood glucose 2 h after lunch (1.452, P = 0.021) and A1C (1.732, P = 0.004); and 2) for mortality, blood glucose 2 h after lunch (1.846, P = 0.001) and A1C (1.896, P = 0.004).

CONCLUSIONS

In type 2 diabetes, both postprandial blood glucose and A1C predict cardiovascular events and all-cause mortality in a long-term follow-up.

Evaluation of a simple policy for pre- and post-prandial blood glucose self-monitoring in people with type 2 diabetes not on insulin

BACKGROUND AND AIMS

Since there is no agreement on regimens of self-monitoring of blood glucose (SMBG) in type 2 diabetes not on insulin, we evaluated the effects of a simple SMBG policy taking into account compliance.

METHODS AND RESULTS

273 type 2 diabetic patients not on insulin with HbA1c >7% attending our Diabetes Clinic and already using SMBG were randomized as follows: Group A, one BG profile/month with fasting and post-prandial values; Group B, one BG profile every 2 weeks with pre- and post-prandial values. Patients were followed-up by the same team every 3 months with the same education and treatment policies. At 3 and 6 months, SMBG profiles were evaluated and HbA1c measured. SMBG was carried out as recommended by 73% of Group A and 44% of Group B patients. In compliant patients, HbA1c and BG were unchanged in Group A whereas in Group B fasting, pre-prandial and two out of three post-prandial BG values were reduced and HbA1c decreased from 8.09+/-0.84% to 7.60+/-0.73% (p<0.001). The influence on BG control was similar for the two policies when compliance was not considered.

CONCLUSIONS

The more intensive SMBG policy considered is associated with improvements in glycaemic control in compliant subjects.

Hypoglycaemia in Type 2 diabetes

The primary cause of hypoglycaemia in Type 2 diabetes is diabetes medication-in particular, those which raise insulin levels independently of blood glucose, such as sulphonylureas (SUs) and exogenous insulin. The risk of hypoglycaemia is increased in older patients, those with longer diabetes duration, lesser insulin reserve and perhaps in the drive for strict glycaemic control. Differing definitions, data collection methods, drug type/regimen and patient populations make comparing rates of hypoglycaemia difficult. It is clear that patients taking insulin have the highest rates of self-reported severe hypoglycaemia (25% in patients who have been taking insulin for > 5 years). SUs are associated with significantly lower rates of severe hypoglycaemia. However, large numbers of patients take SUs in the UK, and it is estimated that each year > 5000 patients will experience a severe event caused by their SU therapy which will require emergency intervention. Hypoglycaemia has substantial clinical impact, in terms of mortality, morbidity and quality of life. The cost implications of severe episodes-both direct hospital costs and indirect costs-are considerable: it is estimated that each hospital admission for severe hypoglycaemia costs around pound1000. Hypoglycaemia and fear of hypoglycaemia limit the ability of current diabetes medications to achieve and maintain optimal levels of glycaemic control. Newer therapies, which focus on the incretin axis, may carry a lower risk of hypoglycaemia. Their use, and more prudent use of older therapies with low risk of hypoglycaemia, may help patients achieve improved glucose control for longer, and reduce the risk of diabetic complications.

Glucose metabolism and hyperglycemia

Islet dysfunction and peripheral insulin resistance are both present in type 2 diabetes and are both necessary for the development of hyperglycemia. In both type 1 and type 2 diabetes, large, prospective clinical studies have shown a strong relation between time-averaged mean values of glycemia, measured as glycated hemoglobin (HbA1c), and vascular diabetic complications. These studies are the basis for the American Diabetes Association's current recommended treatment goal that HbA1c should be <7%. The measurement of the HbA1c concentration is considered the gold standard for assessing long-term glycemia; however, it does not reveal any information on the extent or frequency of blood glucose excursions, but provides an overall mean value only. Postprandial hyperglycemia occurs frequently in patients with diabetes receiving active treatment and can occur even when metabolic control is apparently good. Interventional studies indicate that reducing postmeal glucose excursions is as important as controlling fasting plasma glucose in persons with diabetes and impaired glucose tolerance. Evidence exists for a causal relation between postmeal glucose increases and microvascular and macrovascular outcomes; therefore, it is not surprising that treatment with different compounds that have specific effects on postprandial glucose regulation is accompanied by a significant improvement of many pathways supposed to be involved in diabetic complications, including oxidative stress, endothelial dysfunction, inflammation, and nuclear factor-kappaB activation. The goal of therapy should be to achieve glycemic status as near to normal as safely possible in all 3 components of glycemic control: HbA1c, fasting glucose, and postmeal glucose peak.

Effect of the diabetes outpatient intensive management programme on glycaemic control for type 2 diabetic patients

AIM

The purpose of this study was to examine the effect of the diabetes outpatient intensive management programme (DOIMP) on glycaemic control over a 12 week follow-up period for type 2 diabetic patients in Korea.

BACKGROUND

Diabetic complications can be prevented if the glycaemic status of diabetes patients is maintained within a nearly normal range. Patient education is critical in controlling blood glucose levels of patients with diabetes within the optimal range.

METHODS

DOIMP was composed of multidisciplinary education, complication monitoring and telephone counselling. Twenty-five patients in the intervention group participated in the DOIMP and 24 patients in the control group were briefed on the conventional description of diabetes mellitus by diabetes education nurses.

RESULTS

Patients in the intervention group had a mean decrease of 2.3%, which those in the control group having a mean decrease 0.4% in glycosylated haemoglobin (HbA(1)c). There was no difference between the two groups in the change in fasting blood glucose (FBG) and two-hour postprandial blood glucose (2-h PBG). The proportion of the patients with HbA(1)c <7% was higher in the intervention group than in the control group at the post-test compare with the pretest.

CONCLUSION

DOIMP can reduce HbA(1)c in type 2 diabetes patients.

RELEVANCE TO CLINICAL PRACTICE

These findings indicated that DOIMP could be effective in glycaemic control in type 2 diabetes patients.

[Contribution of post-breakfast plasma glucose to the glycemic control of type 2 diabetic patients]

Epidemiological studies have documented that postprandial hyperglycemia is the main risk factor for cardiovascular diseases. It has been established that glycated hemoglobin (HbA1C) provides an integrated measure of plasma glucose (PG) of the last 2-3 months. However, the relative contribution of fasting PG (FPG) and postprandial PG (PPG) to the HbA1C value is controversial.

OBJECTIVE

To evaluate FPG and PPG contributions to the HbA1C value in patients with type 2 diabetes mellitus (DM2).

METHODS

53 subjects with stable DM2 were studied. They were treated with oral anti-diabetic agents (n = 27) and/or insulin (n = 26). Each subject went to 3 visits at 2-month-intervals. On each visit, FPG, PPG (2 h after breakfast and lunch), and HbA1C were measured and we provided breakfast and lunch according to their meal habits. PG was measured by glucose-oxidase and HbA1C by ion-exchange chromatography. Statistical analysis was performed by correlation coefficients at a < 0.05 P value.

RESULTS

Correlations were stronger between HbA1C and post-breakfast PG (r: 0.66-0.48), mean FPG (r: 0.64-0.41), glucose area under the curve (r: 0.64-0.46), and mean PPG (r: 0.59-0.41).

CONCLUSIONS

Measurement of post-breakfast PG showed to be another valuable tool for type 2 diabetic glucose control monitoring.

Hypoglycaemia in elderly diabetic patients

Occurring in the elderly diabetic patients, hypoglycaemia may have serious consequences in terms of morbidity and mortality, but this severe prognosis is nowadays less frequently observed. The clinical manifestations may be somewhat different from those observed in young subjects: symptoms are less frequent, generally neurologic manifestations. The rate of severe hypoglycaemia remains low (about 1.4 episode per 100 patient-years), but increases rapidly in the very elderly and also with insulin therapy, co-morbid conditions especially renal insufficiency, and associated treatments, as well as with unawareness of symptoms. Prevention requires reinforced education for the patient and caregiver, particularly concerning diet, knowledge of signs of hypoglycaemia, and appropriate treatment. Self-monitoring of blood glucose, by the patient when possible, or by a familial or medical caregiver, should be encouraged in order to detect asymptomatic episodes of hypoglycaemia and better adapt antidiabetic treatment.

Hypoglycemia in type 2 diabetes: a critical review

Hypoglycemia is the most important barrier to tight glycemic control. Although severe hypoglycemia is uncommon, milder events can occur so often that they represent a deterrent to intensifying treatment. High-risk patient behaviors are the most important cause for episodes for which a cause can be identified. Because symptoms are an unreliable way of establishing the diagnosis, SMBG should be considered for the patients at highest risk, particularly as they approach their glycemic targets. SMBG is superior to HbA1c in forecasting the hypoglycemia rate because it provides information about glucose variability--an independent risk factor. Patient education and medication changes are potential ways of reducing the hypoglycemia rate. However, it remains to be proven that patient education is beneficial in this regard.

An overview of the rationale for pharmacological strategies in type 2 diabetes: from the evidence to new perspectives

Therapeutic strategies in type 2 diabetic patients should not only integrate both the targets and indications of the different therapies but should be also a compromise between the patient's and physician's goals and willingnesses. The rationale for therapeutic targets is based on recommendations that differ from one country to another. Even though HbA1c remains the "gold standard", monitoring of blood glucose at fasting and postprandial time-points is a complementary tool for estimating both the quality and safety of diabetic control. Despite the lack of available strong evidence-based data it seems that achieving glucose levels < 130 mg/dl at fasting and < 180 mg/dl or < 140 mg/dl over postbreakfast or postlunch periods, respectively, might be a reasonable goal in most countries. The choice of appropriate strategies for treating type 2 diabetic patients should ideally be based on pathophysiological considerations. However for practical reasons, decisions for initiating or completing antidiabetic treatments are usually made by using such simple parameters as HbA1c and plasma glucose levels. The bridge between pathophysiological and clinical rationales can be obtained from the analysis of the relative contributions of fasting and postprandial glucose to the overall hyperglycaemia. In patients with HbA1c < 7.3%, postprandial glucose makes the major contribution to the overall hyperglycaemia, whereas the contribution of fasting glucose becomes progressively predominant in patients with HbA1c > 7.3%. As a consequence of these observations, initiation of antidiabetic treatments or implementation of second-line therapies should be aimed at reducing either postprandial excursions or fasting hyperglycaemia according to whether HbA1c levels are found respectively below or above a cut-off value of 7.3%.

Self-monitoring of blood glucose in diabetic patients: from the least common denominator to the greatest common multiple

Self-monitoring of blood glucose (SMBG) is recognized as necessary in insulin-treated diabetic patients. There is less evidence for the regular use of SMBG in non-insulin-using type 2 diabetic patients. The rationale for an appropriate regimen of SMBG might be to have at least one time-point of monitoring included within each of the 3 periods of daytime i.e. fasting, postprandial and postabsorptive periods. Interventional trials have indicated that a 4-to 5-point daily profile represents an optimal regimen for SMBG in type 1 diabetic patients with satisfactory diabetic control. This type of SMBG includes 4 daily glucose determinations (3 before each meal and one at bedtime) and one weekly monitoring at 3: 00 am. However additional determinations should be made within postprandial states, particularly when rapid insulin analogues or pump-treatments are used. In non-insulin-using type 2 diabetic patients, studies of diurnal glycemic profiles have indicated that postprandial glucose is an important contributor to HbA1c and that mid-morning hyperglycemia is the "weakest link" of metabolic control. Therefore mid-morning glucose testing should be recommended when HbA1c levels are not correctly controlled. Furthermore, extended postlunch determinations at 5: 00 pm can be helpful for checking both the quality and safety of diabetic control in such patients. The frequency and timing of SMBG depend both on the type (1 or 2) of diabetes and should be a compromise between optimal and minimal regimens.

What does postprandial hyperglycaemia mean?

AIMS

The potential importance of postprandial glucose (PPG) control in the development of complications in Type 2 diabetes is much debated. The recent American Diabetes Association (ADA) consensus statement discussed the role of postprandial hyperglycaemia in the pathogenesis of diabetic complications and concluded that the relationship between PPG excursions and the well-established risk factors for cardiovascular disease (CVD) should be further examined. Using the ADA statement as a starting point and including the more recent American College of Endocrinology guidelines on glycaemic control, a panel of experts in diabetes met to review the role of PPG within the context of the overall metabolic syndrome, in the development of complications in Type 2 diabetes.

RESULTS

Post-prandial hyperglycaemia is a risk indicator for micro- and macrovascular complications, not only in patients with Type 2 diabetes but also in those with impaired glucose tolerance. In addition, the metabolic syndrome confers an increased risk of CVD morbidity and mortality. The debate focused on the relative contributions of postprandial hyperglycaemia, the metabolic syndrome and, in particular, raised triglyceride levels in the postprandial state, to the development of cardiovascular complications of diabetes.

CONCLUSIONS

The panel recommended that in the prevention and management of microvascular complications of Type 2 diabetes, targeting both chronic and acute glucose fluctuations is necessary. Lowering the macrovascular risk also requires control of (postprandial) triglyceride levels and other components of the metabolic syndrome.

Global assessment for quality and safety of control in type 2 diabetic patients

BACKGROUND

HbA1c (glycated haemoglobin) suffers from obvious limitations in type 2 diabetic patients at risk of hypoglycaemia or requiring rapid therapeutic adjustments. This study was conducted to discern whether the monitoring of one particular plasma glucose (PG) value of the diurnal profile can be used in such situations.

DESIGN

Four diurnal PG concentrations (at 08:00, 11:00, 14:00 and 17:00 h) were measured in standardized conditions in 480 (246 men, 234 women) noninsulin-using type 2 diabetic patients. Sensitivities for predicting treatment success, i.e. HbA1c<7%, with a specificity > or =90% were calculated and compared using receiver-operating characteristic (ROC) curves.

RESULTS

The probabilities (areas under ROC curves) for predicting HbA1c<7% were significantly higher at 11:00, 14:00 and 17:00 h than at 08:00 h. The optimal PG cut-off values for predicting treatment success were, respectively, 6, 9, 7 and 6 mmol L(-1) at 08:00 h, 11:00, 14:00 and 17:00 h. In most patients the lowest PG values of the diurnal profile were at 17:00 h, and 17.5% of the patients with HbA1c<7% (54.5% of them treated with sulphonylureas) exhibited a PG value less than 4.4 mmol L(-1) at 17:00 h (P=0.0034 vs. the other timepoints).

CONCLUSIONS

Glucose monitoring at 17:00 h, i.e. during the extended postlunch period, appears as a global marker of control in noninsulin-using type 2 diabetic patients both for detecting patients at risk of hypoglycaemia and for assessing the short-term quality of diabetic control.

Blood glucose pre-prandial baseline decreases from morning to evening in type 2 diabetes: role of fasting blood glucose and influence on post-prandial excursions

BACKGROUND

To know the relationships between pre- and postprandial blood glucose (BG), i.e. BG profile shape, is a requisite for an appropriate therapy for type 2 diabetic patients. In non diabetic subjects, pre-breakfast, pre-lunch and pre-dinner BG are similar, so that BG postprandial excursions are superimposed on a stable BG preprandial baseline. We aimed to clarify: (a) whether BG preprandial baseline is stable also in type 2 diabetes and (b) whether fasting BG (FBG) influences the slope of BG preprandial baseline and the relationships between pre- and postprandial BG.

DESIGN

We evaluated self-measured BG profiles of 237 type 2 diabetic patients on diet alone (M/F, 152/85; age 58.6 +/- 0.7 years; years from diagnosis 4.8 +/- 0.6; BMI 28.0 +/- 0.3 kg m-2): 536 profiles containing preprandial BG (corresponding HbA1c 6.8 +/- 0.06%) and 208 profiles containing both pre- and postprandial BG (corresponding HbA1c 6.8 +/- 0.09%). The profiles, measured by nurses, of 866 type 2 diabetic patients on diet alone were also considered (corresponding HbA1c 6.7 +/- 0.04%).

RESULTS

In self-measured profiles containing only preprandial BG: (i) FBG (6.77 +/- 0.07 mmol L(-1)) is higher than pre-lunch BG (6.09 +/- 0.07 mmol L(-1)), P = 0.0001) and pre-dinner BG (5.84 +/- 0.06 mmol L(-1)), P =0.0001); (ii) the delta value between FBG and pre-dinner BG is correlated with FBG (r = 0.57, P = 0.0001), the highest FBG, the steepest the fall of BG preprandial baseline throughout the day. This trend is confirmed in profiles measured by nurses. In profiles containing both pre- and postprandial BG: (i) there is a trend to preprandial BG fall (P = 0.0001) and to postprandial BG increase (P = 0.0001) from morning to evening; (ii) postprandial excursions are influenced and sometimes masked by the slope of BG preprandial baseline, thus, in profiles with FBG < or = 6.7 mmol L(-1), all postprandial values are higher than FBG (P = 0.0001), whereas in profiles with FBG > 7.8 mmol L(-1), postprandial values are not significantly higher than FBG.

CONCLUSION

In type 2 diabetes, the shape of BG profiles changes in relation to FBG, because it deeply influences the slope of BG preprandial baseline on which postprandial excursions are superimposed. Thus, before planning treatment policies, not only the extent of fasting and postprandial hyperglycaemia, but also the shape of profiles should be considered, to safely correct hyperglycaemia without inducing hypoglycaemia.

Glucose counterregulation in Type 2 diabetes mellitus

Glucose counterregulatory failure and hypoglycaemia unawareness frequently complicate treatment of Type 1 diabetes mellitus, especially when aiming for intensive metabolic control. Since tight metabolic control reduces microvascular long-term complications in Type 2 diabetes mellitus, the integrity of glucose counterregulation in Type 2 diabetic patients is important. Using a Medline search, we identified 12 studies in which counterregulatory responses to insulin-induced hypoglycaemia were compared between Type 2 diabetic patients and appropriate controls. A review of these studies showed that some patients with Type 2 diabetes mellitus develop mild counterregulatory dysfunction and reduced awareness of insulin-induced hypoglycaemia. Some studies suggested an association between counterregulatory impairment and intensity of metabolic control. We speculate that the relatively low frequency of (severe) hypoglycaemic events in Type 2 diabetes may explain why glucose counterregulation remains unaffected in most patients. We hypothesize that residual beta-cell reserve and insulin resistance provide protection against severe hypoglycaemia and limit impaired counterregulation. Diabet. Med. 18, 519-527 (2001)

Self-monitoring of blood glucose in overweight type 2 diabetic patients

Self-monitoring of blood glucose (SBGM) is widely recommended for both type 1 and type 2 diabetic patients despite the lack of evidence of benefit in glucose control or as an aid in weight loss in type 2 subjects. This study tested the hypothesis that combined use of SMBG and dietary carbohydrate (CHO) counting, using the blood monitoring results to shape dietary CHO quotas, is beneficial in managing type 2 diabetes. Twenty-three overweight (body mass index, BMI 27.5-44 kg/m2) patients aged 40-75 participated in a 28-week behavioral weight control program. Baseline hemoglobin HbA1c ranged between 9.5% and 13.5% (normal range 5.5%-7.7%). Subjects were matched for weight, sex, and HbA1c and assigned to small (4-8 participants) groups which met weekly for 12 weeks and then monthly for 16 weeks. After 8 weeks, the groups were randomized either to continue the behavioral program or to have SMBG and dietary CHO counting. Glucose monitoring was performed 6 times daily (pre- and 2 h postprandially) for the first month, focusing on the meal increment and correlating this to dietary CHO intake. Weight loss was identical in both groups during the year of follow-up. The HbA1c level showed a progressive decline in experimental subjects (P < 0.05), whereas there was no improvement in control subjects.

Glibenclamide vs gliclazide in type 2 diabetes of the elderly

The objective of this study was to compare the effect of two sulphonylureas on the frequency of hypoglycaemic events and glycaemic control in elderly patients with Type 2 diabetes. Twenty-two untreated elderly patients were treated with glibenclamide or gliclazide in a randomized double-blind fashion. Prior to treatment, a biochemical profile, an oral glucose tolerance test, and a 2-h hyperglycaemic glucose clamp (glucose 5.4 mmol l-zs-1 above baseline) were performed. Patients were seen regularly over 6 months to assess glycaemic control and the frequency of hypoglycaemic reactions. Hyperglycaemic clamp studies and oral glucose tolerance tests were repeated at 1 and 6 months. The area under the curve for the oral glucose tolerance test (glibenclamide: 15.5 +/- 0.7; gliclazide: 14.9 +/- 0.8 mmol l-1 (p = NS)) and the haemoglobin A1C (glibenclamide: 7.4 +/- 0.2%; gliclazide: 7.9 +/- 0.5% (p = NS)) were similar at 6 months. Hypoglycaemic reactions were significantly more frequent with glibenclamide than with gliclazide: 17 vs 4 (p < 0.01). Insulin sensitivity index (ml kg-1 min-1 pmol-1 x 100) was increased significantly by glibenclamide but not gliclazide (glibenclamide: 0.284 +/- 0.116 (baseline) vs 0.518 +/- 0.102 (6 months) (p < 0.05), gliclazide: 0.260 +/- 0.048 (baseline) vs 0.358 +/- 0.048 (6 months) (p = NS)). We conclude that glycaemic control was equivalent with the two drugs but the incidence of hypoglycaemic reactions was significantly greater with glibenclamide probably because this drug increases insulin sensitivity to a greater degree.

Rational use of sulfonylureas

The clinical use of sulfonylureas described in this article is both rational and effective for diabetic patients. Sulfonylureas are not used (1) in patients with insulin-dependent (type I) diabetes, because they are completely ineffective or (2) in patients with non-insulin-dependent (type II) diabetes who respond satisfactorily to diet, because they are unnecessary. In a patient with type II diabetes who has few or no symptoms but does not respond satisfactorily to diet, a sulfonylurea is introduced at a low dose, with gradual increases until a satisfactory response occurs, thus avoiding hypoglycemia. When symptoms of type II diabetes are marked, initiation of therapy with maximum doses of a sulfonylurea quickly distinguishes patients who need insulin therapy from those who have a good chance of responding to an oral drug. Abuse of sulfonylureas occurs when patients who could benefit from diet alone are treated with the drugs unnecessarily or, more often, when patients with poorly controlled disease continue to take maximum doses of the drugs. The usual situation is one in which the patient refuses insulin therapy or the physician does not suggest starting it. In other cases, the poorly controlled patient may be allowed to continue with a combination of a sulfonylurea and an ineffective dose of insulin. In this circumstance, the oral drug should be discontinued and insulin doses increased until control is more satisfactory. Because evidence is so compelling that near euglycemia has a beneficial effect on diabetic retinopathy, nephropathy, and neuropathy, physicians really do patients a disservice by misusing sulfonylureas.

A comparison of the predictive power for overall blood glucose control of a 'good' fasting level in type 2 diabetic patients on diet alone or with oral agents

The European NIDDM Policy Group classifies both fasting and post-prandial blood glucose concentrations into 'good', 'acceptable', and 'poor' categories. The aim of the present study was to evaluate whether a 'good' fasting blood glucose concentration in Type 2 diabetic patients on diet or diet + oral hypoglycaemic agents is able to predict 'good' blood glucose values throughout the day, and therefore to discover whether or not it is necessary to perform blood glucose profiles in Type 2 diabetic patients when their fasting value is 'good'. Capillary blood glucose profiles (n = 417) were measured in 287 Type 2 diabetic patients, on diet alone (279 profiles), or on diet + tablets (138 profiles). We observed that 66% of profiles on diet and 44% of profiles on diet + tablets had only 'good' blood glucose concentrations (p less than 0.001). Eleven percent of profiles on diet and 30% of profiles on diet + tablets included 'poor' blood glucose concentrations (p less than 0.001). Despite matched fasting blood glucose concentrations (diet 5.69 +/- 0.04 (+/- SE) vs tablets 5.75 +/- 0.05 mmol l-1), levels were higher in the diet + tablet treated patients at all later time-points (p less than 0.01-0.001). HbA1c was significantly higher in tablet-treated patients than in patients on diet alone (6.6 +/- 0.1 vs 5.9 +/- 0.1%, p less than 0.001), and correlated with the mean blood glucose concentration (r = 0.43, p less than 0.001) but not with the fasting glucose concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)