Metabolic disorders associated with uncontrolled hypertension

AIM

To examine the prevalence and characteristics of uncontrolled hypertension (HT).

METHODS

A cross-sectional community-based study (1992-93) was carried out in Skara, Sweden, including 894 patients who consecutively underwent an annual follow-up at the hypertension outpatient clinic in primary care. Controlled HT was defined as diastolic blood pressure (DBP) < or =90 mmHg and systolic blood pressure (SBP) < or =160 mmHg and was used as reference. Uncontrolled DBP was defined as DBP >90 mmHg regardless of SBP level, and isolated uncontrolled SBP was defined as SBP >160 mmHg and DBP < or =90 mmHg. Proportions were age-standardized using the Skara population as reference.

RESULTS

The prevalence of uncontrolled HT was 43% (isolated uncontrolled SBP 18% and uncontrolled DBP 25%). Both men and women with isolated uncontrolled SBP were older (73 years, CI: 70-75; and 73 years; CI: 72-75) than patients with controlled HT (64 years, CI: 63-66; and 65 years, CI: 64-66). Men and women with known cardiovascular disease (CVD) less often had isolated uncontrolled SBP (OR: 0.4, CI: 0.2-0.9; and OR: 0.5, CI: 0.3-0.9), whereas men and women with known diabetes more often had uncontrolled DBP (OR: 2.3, CI: 1.3-4.1; and OR: 3.3, CI: 1.9-5.7). Men with known CVD less often had uncontrolled DBP (OR: 0.5, CI: 0.3-1.0, p = 0.04), and men with fasting blood glucose >5.5 mmol/l more often had isolated uncontrolled SBP (OR: 1.9, CI: 1.0-3.5, p = 0.04). In women, the following high risk factor levels were associated with uncontrolled DBP: fasting blood glucose >5.5 mmol/l (OR: 1.4, CI: 1.1-1.8), fasting triglycerides > or =1.7 mmol/l (OR: 1.4, CI: 1.1-1.8), body mass index (BMI) >30 kg/m2 (OR: 1.5, CI: 1.1-1.9), waist/hip ratio (WHR) >0.85 cm/cm (OR: 1.7, CI: 1.3-2.2), insulin resistance (homeostasis model assessment (HOMA) >third quartile) (OR: 1.4, CI: 1.1-1.9) and microalbuminuria (OR: 3.2, CI: 1.7-6.2).

CONCLUSION

Uncontrolled DBP is in both sexes related to type 2 diabetes, whereas isolated uncontrolled SBP is related to older age. In women, uncontrolled DBP, furthermore, is related to several other CVD risk factors of the metabolic syndrome. Patients with uncontrolled DBP should be carefully evaluated for metabolic disorders.

Glycaemic control, disease duration and beta-cell function in patients with Type 2 diabetes in a Swedish community. Skaraborg Hypertension and Diabetes Project

AIMS

To examine determinants for glycaemic control in primary care patients with Type 2 diabetes.

METHODS

In a community-based surveillance of primary care patients with Type 2 diabetes, 190 men and 186 women were consecutively identified and examined for cardiovascular risk factors. Insulin resistance and beta-cell function were estimated using homeostasis model assessment (HOMA). Good glycaemic control was defined as HbA(1c) < 6.5%.

RESULTS

Following adjustment for age and gender, HbA(1c) > or = 6.5% was associated with duration of diabetes (10.6 vs. 6.4 years, P < 0.001), lower levels of serum insulin (6.3 vs. 8.0 mU/l, P = 0.012), higher serum triglyceride levels (2.0 vs. 1.7 mmol/l, P = 0.002) and impairment of beta-cell function (HOMA index 19.5 vs. 45.8, P < 0.001). The association between HbA(1c) levels and duration remained with adjustment for age, gender, waist-hip ratio (WHR) and serum triglycerides (odds ratio (OR) for HbA(1c) > or = 6.5% by 5 years diabetes duration = 1.7; 95% confidence interval (CI) 1.4--2.1) but was lost following additional adjustment for beta-cell function (OR for HbA(1c) > or = 6.5% = 1.3; 95% CI 0.96-1.7). In a separate linear regression with beta-cell function as the dependent variable there was a significant association with HbA1c after adjustments for differences in age, gender, WHR, serum triglyceride levels and diabetes duration (P < 0.001).

CONCLUSIONS

Increasing HbA1c by time was associated with declining beta-cell function.

Effects and serum levels of glibenclamide and its active metabolites in patients with type 2 diabetes

OBJECTIVE

To study the effects and serum levels of glibenclamide (Gb) and its active metabolites in patients on chronic Gb medication on different daily doses.

MATERIAL AND METHODS

Fifty patients with type 2 diabetes on regular Gb therapy (1.75-14.0 mg daily). Blood samples were taken immediately before and 90 min after regular Gb intake. A standardized breakfast was served 30 min after drug intake. Serum insulin and proinsulin levels were determined by ELISA methods without cross-reactivities. Serum drug levels were determined by HPLC. Fischer's R to Z-test (correlation coefficients) and paired Student t-tests were used when comparing values within the entire group and unpaired non-parametric Mann-Whitney tests were used when comparing high and low dose levels. A p-value < 0.05 was considered significant.

RESULTS

There were significant correlations between daily Gb dose, on the one hand, and, on the other, HbAlc (r = 0.55), Delta-insulin (r = - 0.59) and Delta-proinsulin (r = - 0.52) levels. Significant correlations between Gb therapy duration and insulin (r = - 0.40) and proinsulin (r = - 0.34) secretion and between Gb dose and ratio proinsulin/insulin (RPI) at both time points (r = 0.32 and 0.30) were also found. The RPI was lower after Gb intake. In patients on > or = 10.5 mg steady state serum metabolite levels (Ml and Ml + M2) were higher (29(0-120) and 33 (0-120) ng/ml) than those of Gb itself (18(0-64) ng/ml). A great inter-subject variability in Gb levels at both time points was seen.

CONCLUSIONS

Our results indicate that, in patients on chronic medication, Gb is capable of stimulating both insulin and proinsulin secretion; the effect on insulin release is relatively greater. The effect was more pronounced in patients on a low Gb dose, either because of less impaired beta-cells in those receiving low doses, or due to reduced sulphonylurea sensitivity in those on high dosage (down-regulation). In patients on a daily dose of 10.5 mg or more, serum metabolite levels of clinical relevance were demonstrated; the metabolites may contribute to hypoglycaemic events.

The NEPI antidiabetes study (NANSY). 1: short-term dose-effect relations of glimepiride in subjects with impaired fasting glucose

AIM

NANSY is a randomised, placebo-controlled Swedish-Norwegian study which aims to include 2 x 1112 male and female subjects with impaired fasting glucose (IFG), to assess whether conversion to type 2 diabetes can be delayed by addition of sulphonylurea to dietary regulation and increased exercise. This pilot study was conducted to find the optimum dose of glimepiride in NANSY.

METHODS

In a double blind trial in primary care 25 IFG subjects were in random order exposed to single doses and one-week treatments with 0 (placebo), 0.5, 1.0 and 2.0 mg glimepiride once daily. The optimum dose was assessed by measuring blood glucose during oral 75 g glucose tolerance test (OGTT), comparing fasting blood glucose, and the area under the blood glucose curve (AUC), and by monitoring hypoglycaemic events.

RESULTS

With single doses, there was a clear dose-response relationship for the reduction in AUC, with a statistically significant difference only between placebo (mean 1981, 95% confidence intervals (CI) 1883-2078) and 2 mg glimepiride (mean 1763, 95% CI 1665-1861). However, following 1-week treatments, the only significant difference was between placebo (mean 1934, 95% CI 1856-2012) and 1 mg glimepiride (mean 1714, 95% CI 1637-1792). Correspondingly, the only statistically significant difference in fasting blood glucose day 7 was between placebo (5.87 mmol/l, 95% CI 5.68-6.05 mmol/l) and 1 mg glimepiride (5.42 mmol/l, 95% CI 5.21-5.62 mmol/l). Chemical hypoglycaemia was common but hypoglycaemic symptoms were rare and similar between the active doses, and easily countered by the subjects.

CONCLUSIONS

The sulphonylurea dose-effect curve may be bell-shaped, perhaps due to down regulation of sulphonylurea receptors during chronic exposure. Alternatively, the finding could be a rebound phenomenon, secondary to preceding hypoglycaemia. The optimum dose for NANSY was found to be 1 mg glimepiride.

Diastolic blood pressure and area of residence: multilevel versus ecological analysis of social inequity

STUDY OBJECTIVES

To study geographical differences in diastolic blood pressure and the influence of the social environment (census percentage of people with low educational achievement) on individual diastolic blood pressure level, after controlling for individual age and educational achievement. To compare the results of multilevel and ecological analyses.

DESIGN

Cross sectional analysis performed by multilevel linear regression modelling, with women at the first level and urban areas at the second level, and by single level ecological regression using areas as the unit of analysis.

SETTING

Malmö, Sweden (population 250 000).

PARTICIPANTS

15 569 women aged 45 to 73, residing in 17 urban areas, who took part in the Malmö Diet and Cancer Study (1991-1996).

MAIN RESULTS

In the "fixed effects" multilevel analysis, low educational achievement at both individual (beta=1.093, SE=0.167) and area levels (beta=2.966, SE=1.250) were independently associated with blood pressure, although in the "random effects" multilevel analysis almost none of the total variability in blood pressure across persons was attributable to areas (intraclass correlation=0.3%). The ecological analysis also found an association between the area educational variable and mean diastolic blood pressure (beta=4.058, SE=1.345).

CONCLUSIONS

The small intraclass correlation found indicated very marginal geographical differences and almost no influence of the urban area on individual blood pressure. However, these slight differences were enough to detect an effect of the social environment on blood pressure. The ecological study overestimated the associations found in the "fixed" effects multilevel analysis, and neither distinguished individual from area levels nor provided information on the intraclass correlation. Ecological analyses are inadequate to evaluate geographical differences in health.

Prescribing, prescription costs and adherence to formulary committee recommendations: long-term differences between physicians in public and private care

BACKGROUND

In southern Sweden, many general practitioners (GPs) participate in an extensive postgraduate drug education programme, and many health centres are also fed back crude local drug statistics from pharmacists in the area. Private physicians and hospital physicians have not participated in these programmes.

OBJECTIVE

The drug prescribing habits and costs of GPs, hospital physicians and private physicians were compared.

METHODS

Each March, from 1990 to 1997, all prescriptions dispensed at the eight pharmacies in Växjö, a city and municipality in southern Sweden, were registered, specifying drug(s) prescribed, price, patient's age, sex and area of residence, and prescriber's place of work and category.

RESULTS

Overall, the costs of prescribed drugs increased with time, even in 1997 when the prescribing volume was reduced due to changes in the reimbursement system. The cost increase was caused by increased prescribing of newer, more expensive drug alternatives. However, within each of the eleven major drug groups, the drugs prescribed by GPs were less expensive than those prescribed by hospital physicians and, particularly, private physicians. Moreover, even though GPs prescribed more and a wider range of drugs, they also had a higher degree of adherence to the recommendations by the formulary committee.

CONCLUSION

GPs prescribed less expensive drugs and had a higher degree of adherence to the recommendations by the formulary committee than other categories of physicians. One reason for these differences may be that the GPs participated in regional and local educational activities aimed at the rationalisation of drug prescribing.

Differences in pharmacotherapy and in glucose control of type 2 diabetes patients in two neighbouring towns: a longitudinal population-based study

AIM

To compare prescribing, dosage and blood glucose levels in patients with type 2 diabetes in two communities with differences in anti-hyperglycaemic drug utilization.

METHODS

A retrospective longitudinal (1984-1994) population-based study in two neighbour towns in southern Sweden. The mean prescribed daily dose was expressed as a fraction of the Defined Daily Dose (DDD) for each drug.

RESULTS

In town A, prescribing of oral agents and insulin was predominantly made by one specialized diabetes clinician, while in town B it was spread among several different general practitioners and one specialist. Altogether 44 636 medical visits by 2348 patients were identified. In each town, about 40% of the patients were treated without anti-hyperglycaemic drugs, about 40% with oral agents and about 20% with insulin. However, there were pronounced between-town differences in dosage and glucose control. The mean prescribed daily dose of sulphonylurea monotherapy decreased gradually from approximately 0.7 to approximately 0.5 DDD in town B but remained approximately 0.8 DDD in town A. The proportion of patients on both sulphonylurea and metformin increased substantially in town A but not in town B. In these patients, the mean prescribed daily dose of sulphonylurea exceeded 1.0 DDD in both towns, although it decreased with time in town B. The mean prescribed daily dose of insulin increased from 1.05 to 1.2 DDD in town A but remained virtually unchanged at 0.95 DDD in town B. The mean fasting blood glucose was lower in town A than in town B both overall (7.7 vs. 8.8 mmol/l), in those treated without any anti-hyperglycaemic drugs (7.2 vs. 8.1 mmol/l), in those on sulphonylurea monotherapy (8.3 vs. 9.7 mmol/l) and in those treated with insulin (8.1 vs. 10.2 mmol/l).

CONCLUSIONS

Glucose control in routine care was better when most patients were treated by a diabetes specialist and were exposed to more intense pharmacotherapy.

Variation in antibiotic use in the European Union

Data on antibiotic use are not publicly available in most European Union countries. We obtained data for non-hospital antibiotic sales for 1997 from the 15 member states and analysed these according to the Anatomic Therapeutic Chemical classification system, and expressed them as defined daily doses per 1000 people per day. Sales of antibiotics varied more than four-fold: France (36.5), Spain (32.4), Portugal (28.8), and Belgium (26.7) had the highest sales, whereas the Netherlands (8.9), Denmark (11.3), Sweden (13.5), and Germany (13.6) had the lowest. There was also profound variation in use of different classes of antibiotics. Detailed knowledge of antibiotic use is necessary to implement national strategies for optimum antibiotic use, and to address the threat posed by resistant microorganisms.

Association of outpatient utilisation of non-steroidal anti-inflammatory drugs and hospitalised heart failure in the entire Swedish population

OBJECTIVE

Individual-based studies on restricted geographical settings have suggested that non-steroidal anti-inflammatory drugs (NSAIDs) may precipitate congestive heart failure. As NSAID use is very extensive, it might increase the occurrence of symptomatic heart failure in the general population. Therefore, in order to study the impact of NSAID utilisation (prescribed and over the counter) on hospitalised heart failure in an entire country (Sweden), we performed an ecological analysis, a design appropriate for studying large geographical areas.

METHODS

We employed weighted (population size) ecological linear regression to study the association between outpatient utilisation of NSAIDs during 1989-1993 and hospitalised heart failure in 1993 in 283 of Sweden's 288 municipalities. Data were adjusted for age and gender proportions, socio-economic factors, latitude and utilisation of cardiovascular drugs, aspirin, low-dose aspirin and paracetamol.

RESULTS

The unadjusted relative risk of hospitalised heart failure for each increase of one standard deviation of NSAID utilisation (5.8 defined daily doses/1000 inhabitants/day) was 1.23 [95% confidence interval (CI) 1.18, 1.27]. After adjustments, the relative risk was 1.08 (95% CI 1.04, 1.12); the corresponding values if aspirin (non-low-dose) was included as an NSAID were 1.26 (95% CI 1.23, 1.28) and 1.07 (95% CI 1.04, 1.10). There was no such adjusted association with the utilisation of paracetamol-0.95 (95% CI 0.92, 0.98).

CONCLUSION

The NSAID--heart failure association already established by individual-based studies on restricted geographical settings was corroborated in the present ecological study based on the whole population of an entire country (Sweden). Efforts should be made to promote a rational use of NSAIDs in the general population.

Impaired glucose metabolism and obesity in Swedish patients with borderline isolated systolic hypertension: Skaraborg Hypertension and Diabetes Project

AIM

To assess the prevalence of borderline isolated systolic hypertension (borderline ISH), and to examine its association with other cardiovascular risk factors.

METHODS

A cross-sectional community-based study was carried out in 1993-1994 in Skara, Sweden, including 1109 randomly chosen subjects > or = 40 years old. Normotension (NT) was defined as systolic blood pressure (SBP) < 140 and diastolic blood pressure (DBP) < 90 mmHg, borderline ISH as SBP 140-159 and DBP < 90 mmHg and hypertension (HT) as SBP > or = 160 or DBP > or = 90 mmHg or ongoing treatment.

RESULTS

The prevalence of borderline ISH (n = 203) by age was 4% in ages 40-49 years, 15% in ages 50-59 years, 28% in ages 60-69 years and 25% in ages 70-79 years. With borderline ISH as reference, normotensive subjects less often had fasting blood glucose > 5.5 mmol/l (odds ratio (OR): 0.4, 95% CI: 0.26-0.75), BMI > 27 kg/m2 (OR: 0.6, 95% confidence intervals (CI): 0.42-0.85) and known diabetes (OR: 0.4, 95% CI: 0.16-0.95). Hypertensive subjects more often had high density lipoprotein (HDL) cholesterol < 1.0 mmol/l (OR: 2.0, 95% CI: 1.35-2.99), a history of previous cardiovascular disease (CVD) (OR: 1.7, 95% CI: 1.01-2.72), known diabetes (OR: 2.4, 95% CI: 1.29-4.58) and microalbuminuria (men) (OR: 1.9, 95% CI: 1.15-3.11).

CONCLUSION

Borderline ISH is a common condition. It is associated with a more unfavourable risk factor profile than that of normotensive subjects concerning primarily glucose metabolism and obesity. The prevalence of known diabetes increased with the degree of hypertension.

Mortality in elderly men with low psychosocial coping resources using anxiolytic-hypnotic drugs

OBJECTIVE

Insufficient coping with stress may lead to increased susceptibility for disease and death. Use of anxiolytic-hypnotic drugs has been suggested as a coping strategy, and some opinions have proposed their use as preventive medication. The aim of this study was to estimate if use of anxiolytic-hypnotic drugs counters the increased mortality observed in individuals lacking other coping strategies such as emotional support and social participation.

METHODS

A population based cohort study with 10-year (1982/83-1993) survival analysis was performed in 491 men born in 1914, living in the Swedish city of Malmö.

RESULTS

Compared with men with a high level of psychosocial coping resources who did not use anxiolytic-hypnotic drugs, men with a low level of psychosocial coping resources had a higher risk of death irrespective whether they used anxiolytic-hypnotic drugs, RR = 1.7 (95% CI 1.1-2.6) or not RR = 1.8 (95%: 1.3-2.5).

CONCLUSION

Anxiolytic-hypnotic drugs do not seem to counter increased mortality in elderly men with low psychosocial coping resources.

Effects and pharmacokinetics of oral glibenclamide and glipizide in Caucasian and Chinese patients with type-2 diabetes

The effects and kinetics of oral glibenclamide (Gb) and glipizide (Gz) were studied in Caucasian and Chinese patients (ten in each group) with type-2 diabetes. In randomised order, 2.5 mg Gb, 2.5 mg Gz or placebo was given orally before the administration of 75 g oral glucose. Concentrations of insulin and proinsulin were determined using radioimmunoassay (RIA) without cross-reactivities, and sulphonylurea concentrations were determined using high-performance liquid chromatography (HPLC). There were no significant interethnic differences in Gb or Gz effects whether on glucose, insulin or proinsulin/insulin ratio at any time point. Following Gz, however, Chinese patients had greater increments of serum proinsulin at 10-30 min compared with Caucasians. Apart from the maximum plasma concentration (Cmax) and area under the plasma concentration-time curve (AUC) of Gz being higher among the Chinese, no significant interethnic differences in pharmacokinetics were found. It appears that the same dosage principles could be used for Caucasian and Chinese patients with type-2 diabetes when Gb or Gz are prescribed.

Associations between smoking and beta-cell function in a non-hypertensive and non-diabetic population. Skaraborg Hypertension and Diabetes Project

AIMS

An increased risk for Type 2 diabetes in male and female smokers has been associated with insulin resistance. However, this might also be the result of an adverse effect on the beta-cell. The aim of the present study was to examine the association between smoking and beta-cell function.

METHODS

A community-based, cross-sectional observation study. In 1994, a randomized age-stratified sample of men and women aged > or = 40 years in the city of Skara, Sweden, were invited to a survey of cardiovascular risk factors. In all, 1,109 subjects participated (80%). After the exclusion of subjects with known hypertension or diabetes mellitus, 874 subjects remained to explore. Samples were drawn after an overnight fast. Lifestyle (smoking, physical activity, alcohol consumption) was assessed using a questionnaire. Insulin resistance and insulin secretion were estimated using the homeostasis model assessment (HOMA).

RESULTS

Cigarette smoking men (n = 101) had a lower HOMA beta-cell value (58.1), than never-smokers (n = 158, beta-cell value 90.1, P < 0.001). The difference remained with adjustments for age, body mass index, daily alcohol intake and physical exercise habits: 25.9 (95% confidence interval (CI) 9.7-38.8, P = 0.003). Correspondingly, in men the HOMA beta-cell value was lower in current smokers than in ex-smokers (difference 24.3, 95% CI 11.1-35.2, P < 0.001). In women, no significant difference appeared in beta-cell function vs. different smoking status. There was no association between smoking status and insulin resistance.

CONCLUSIONS

At least in men, smoking may interfere with beta-cell function. The prevention of Type 2 diabetes should include strategies to stop smoking.

Increased mortality in Type II diabetic patients using sulphonylurea and metformin in combination: a population-based observational study

AIMS/HYPOTHESIS

This study analysed cause-specific mortality in Type II (non-insulin-dependent) diabetic patients using either sulphonylurea alone or in combination with metformin.

METHODS

Patients were followed from the first day they were taking either the combination or sulphonylurea alone. Odds ratios by Cox regression analyses were adjusted for age, sex, duration of diabetes, study area, year of inclusion and fasting blood glucose at inclusion.

RESULTS

We included 169 patients taking sulphonylurea and metformin in combination and 741 patients taking only sulphonylurea. Mean (range) follow-up time was 6.1 (0.1-13.0) years. The adjusted odds ratio for overall mortality was 1.63 (95% confidence interval 1.27-2.09) in patients taking sulphonylurea and metformin combination vs those using sulphonylurea alone. For mortality from ischaemic heart disease and stroke the adjusted odds ratios were 1.73 (95% confidence interval 1.17-2.55) and 2.33 (95% confidence interval 1.17-4.63), respectively.

CONCLUSION/INTERPRETATION

There was a higher cardiovascular mortality in Type II diabetic patients taking sulphonylurea and metformin in combination than in those taking only sulphonylurea. Hence, it cannot be excluded that this kind of combination therapy possibly increases cardiovascular mortality. It is feasible that the increased mortality was secondary to a more aggressive type of diabetes in the patients using sulphonylurea and metformin in combination. Combination therapy is known to promote additional blood glucose reduction but there is as yet no evidence that a sulphonylurea and metformin combination is more beneficial on micro- or macrovascular disease than sulphonylurea or metformin alone.

Pharmacodynamics and pharmacokinetics of intravenous glibenclamide in Caucasian and Chinese patients with type-2 diabetes

OBJECTIVE

We analysed the kinetics and effects of glibenclamide (Gb) on glucose, insulin and proinsulin secretion in two ethnic groups (10 in each) of type-2 diabetic patients, one of Caucasian, the other of Chinese origin.

BACKGROUND

Diabetes mellitus type 2 is a global disease affecting all ethnic groups. There are ethnic differences in both the prevalence and metabolic characteristics of the disease. Important interethnic pharmacodynamic and pharmacokinetic differences have been reported for several drugs. With few exceptions, detailed studies on sulphonylurea are lacking.

MATERIAL AND METHODS

The patients were studied on two occasions when either no Gb (control) or 1.25 mg Gb was administered i.v., immediately before the administration of a 75-g oral glucose tolerance test. Concentrations of insulin and proinsulin were determined by means of radioimmunoassay without cross-reactivities. Gb concentration was determined using high-performance liquid chromatography. Pharmacodynamic results were calculated using net areas under the curves, with basal values set as zero. A P value less than 0.05 was considered significant.

RESULTS

When glucose was administered orally without Gb, Chinese patients had higher plasma glucose increases at 10 min (7.6 mmol/l x min vs 2.6 mmol/l x min) and higher increases of plasma insulin levels than Caucasians at both 10 min (198 pmol/l x min vs 54 pmol/l x min) and 30 min (2286 pmol/l x min vs 1198 pmol/l x min). When Gb was administered, the plasma glucose increases were reduced, and the increases of serum insulin and proinsulin levels were greater in both ethnic groups. Compared with the basal values (-1 min), proinsulin/insulin ratios (RPI) were lowest at 10-30 min, followed by an increase. Chinese patients had higher increases of serum insulin levels at 10 min (1109 pmol/l x min vs 550 pmol/l x min) and a lower RPI at 30 min (6. 0% vs 7.6%) and 240 min (15.0% vs 21.0%) relative to Caucasians. Serum Gb data were best fitted to a biexponential i.v. model. There were no interethnic differences in any of the pharmacokinetic parameters.

CONCLUSION

In summary, following oral glucose administration without Gb, Chinese type-2 diabetic patients had higher plasma insulin levels but also higher plasma glucose levels during the first 10 min, which might reflect reduced insulin sensitivity or more rapid glucose absorption. Gb augmented glucose-induced release of both insulin and proinsulin in both ethnic groups; the effect on insulin secretion was more pronounced. In conclusion, minor pharmacodynamic but no pharmacokinetic differences were found between the two groups. It seems appropriate to employ the same dosage principles when using Gb in Caucasians and Chinese.

[Combination treatment with insulin and metformin in type 2 diabetes. Improves glycemic control and prevents weight gain]

Type II diabetes patients on insulin often show inadequate glycaemic control and weight gain. The rationale for adding metformin in these cases is that it can reduce insulin resistance. The present article reviews the growing body of clinical documentation supporting combination therapy, i.e. placebo-controlled studies in insulin-treated patients and controlled studies with reference therapies in patients not yet treated with insulin. These studies show improvement of glycaemic control and less weight gain. Insulin dosages can be reduced in both type II and type I diabetes. A combination of insulin and metformin is recommended especially for obese type II diabetes patients on high insulin doses.