Distinguishing between persistent and transient impaired glucose tolerance using a prediction model.

Screening for impaired glucose tolerance (IGT) and Type 2 (non-insulin dependent) diabetes was carried out in 777 people and those with high blood glucose levels completed three 2-h oral glucose tolerance tests (OGTT). Blood lipid levels, fasting and 2-h insulin levels, body mass index, and blood pressure were also measured and family history of Type 2 diabetes recorded. Fifty people were identified with IGT and of these 21 were found to have persistent IGT and 29 transient IGT. A model including the variables body mass index, fasting and 2-h insulin levels, fasting triglycerides and family history of Type 2 diabetes was developed using the Speigelhalter-Knill-Jones weighting method to predict subjects with persistent IGT. This model could be useful in identifying people with persistent IGT and therefore eliminate the need for repeat OGTTs which are time consuming and expensive.     

Rosiglitazone improves insulin sensitivity, glucose tolerance and ambulatory blood pressure in subjects with impaired glucose tolerance.

AIMS: To determine the effects of rosiglitazone on insulin sensitivity, glucose tolerance and ambulatory blood pressure when administered to subjects with persistent impaired glucose tolerance (IGT). METHODS: Eighteen subjects with persistent IGT were randomized to receive rosiglitazone 4 mg twice daily or matching placebo for 12 weeks. Evaluation at baseline and at the end of treatment included measurement of whole body insulin sensitivity during a euglycaemic hyperinsulinaemic clamp and deriving an insulin sensitivity index. Changes in glucose and insulin concentration were determined after oral glucose tolerance test (OGTT) and mixed meal tolerance tests, and 24-h ambulatory blood pressure was monitored. RESULTS: Rosiglitazone significantly improved the insulin sensitivity index by 2.26 micro g/kg per min per pmol/l relative to placebo (P = 0.0003). Four of nine subjects receiving rosiglitazone reverted to normal glucose tolerance and 5/9 remained IGT, although four of these had improved 2-h glucose values. In the placebo group, 1/9 subjects progressed to Type 2 diabetes and 8/9 remained IGT. Following OGTT and meal tolerance test, glucose and insulin area under curve were reduced over 3 and 4 h, respectively. Compared with placebo, ambulatory blood pressure decreased significantly in the rosiglitazone group by 10 mmHg systolic (P = 0.0066) and 8 mmHg diastolic (P = 0.0126). CONCLUSIONS: Consistent with its effects in patients with Type 2 diabetes, rosiglitazone substantially improved whole body insulin sensitivity and the glycaemic and insulinaemic responses to an OGTT and meal tolerance test in subjects with persistent IGT. Furthermore, rosiglitazone reduced systolic and diastolic ambulatory blood pressure in these subjects.     

Loss of the First Phase Insulin Response to Intravenous Glucose in Subjects with Persistent Impaired Glucose Tolerance

Loss of the first phase insulin response to intravenous glucose is one of the earliest detectable defects of beta cell dysfunction in Type 2 diabetes mellitus. Impaired glucose tolerance (IGT) is considered a prediabetic condition, therefore loss of first phase insulin secretion in subjects with IGT would suggest beta cell dysfunction as an early lesion in the development of Type 2 diabetes. Three groups of subjects were studied, 7 subjects with persistent IGT (classified as having IGT at two 75 g oral glucose tolerance tests (OGTT) done 6 months apart), 6 subjects with transient IGT (IGT at the first OGTT, but normal glucose tolerance at a repeat OGTT 6 months later), and 7 normal controls. First phase insulin secretion was studied using an intravenous glucose tolerance test with arterialized blood sampling. Fasting, 3, 4 and 5 min samples were assayed for glucose and insulin (specific two-site immunoradiometric assay). The fasting insulin was similar in all three groups, however the 3 min insulin response was significantly lower in those with persistent impaired glucose tolerance (p < 0.02). Thus subjects with persistent impaired glucose tolerance demonstrated loss of the first phase insulin response as an early indicator of beta cell dysfunction while subjects with transient IGT had a normal insulin response to intravenous glucose. During the OGTT, the 30 min glucose was not significantly different (p = 0.1) but the 30 min insulin to glucose ratio was significantly lower in subjects with persistent IGT (p < 0.03). In the whole group the 30 min insulin to glucose ratio during the OGTT showed a significant correlation with the peak insulin response during the IVGTT (r = 0.76, p < 0.001). This study suggests that beta cell dysfunction with impaired early insulin release is present before the development of Type 2 diabetes.     

Impaired fasting glucose and impaired glucose tolerance in urban population in India.

AIMS: To study prevalence of impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) in urban Indians and their demographic and anthropometric characteristics. METHODS: Data on capillary blood glucose (OGTT), anthropometric and demography details were available in 10 025 subjects (M : F 4711 : 5314) aged > or = 20 years. Glucose tolerance was categorized as normal, isolated IFG, isolated IGT, IFG + IGT and diabetes using the fasting and 2-h blood glucose (2hBG; 75-g glucose load) values. Subjects with known diabetes were excluded. RESULTS: Age-standardized prevalences of IFG, IGT and newly detected diabetes were 8.7%, 8.1% and 13.9%, respectively. IFG was more prevalent in women (9.8%) than in men (7.4%) (chi2 = 13.62, P = 0.0002), while the gender differences in IGT (men 8.4%, women 7.9%) and diabetes (men 13.3%, women 14.3%) were not significant. Body mass index and waist circumference were higher in glucose-intolerant groups than in normal glucose tolerance (NGT). Prevalence of diabetes, IGT and IFG + IGT increased with age. Among the IFG, 4% had diabetes and 27.1% had IGT using 2hBG criteria. In IFG, the fasting and 2hBG values were not correlated. CONCLUSIONS: Prevalences of IFG and IGT were similar in urban Indians and an overlap occurred in only less than half of these subjects. IFG was more common in women. Subjects with IFG were older and had more adverse anthropometric characteristics in comparison with NGT. IFG did not show an increasing trend with age.     

Prevalence of glucose intolerance in primary hyperparathyroidism and the benefit of parathyroidectomy

BACKGROUND: Increased prevalence of diabetes mellitus (DM) in primary hyperparathyroidism (PHPT) is established, but not glucose intolerance (GI), nor benefit from parathyroidectomy on GI. We determined these during management of a continuous series of patients with PHPT routinely followed after surgery. PATIENTS AND METHODS: WHO criteria classified 75 g oral glucose tolerance tests (OGTT) in 51/54 consecutively proven PHPT patients, into normal glucose tolerance (NGT), DM, impaired glucose tolerance (IGT) or impaired fasting glucose (IFG); GI was derived by adding those with DM and IGT/IFG. OGTT were repeated after parathyroidectomy (mean follow up 2.4 +/- SD 1.6 years). Paired student t tests were used to compare fasting and 2-h plasma glucose (PG). RESULTS: At presentation 32/54 patients (59%) had NGT, 10 IGT/IFG (19%) and 12 type 2 DM (22%), nine newly diagnosed. Before parathyroidectomy 17/35 patients had NGT (49%), 18 GI (51%), 12 DM (34%) and 6 IGT/IFG (17%). Five out of six patients with IGT/IFG had NGT, one with NGT developed IGT. At completion 23 patients (66%) had NGT, 12 GI (34%), 4 IGT/IFG (11%) and 8 DM (23%). After parathyroidectomy fasting and 2-h. PG fell in 30/34 normocalcaemic patients not on hypoglycaemic agents, 5.6 +/- 1.0 to 5.4 +/- 0.8 mmol/l, 7.2 +/- 3.0 to 6.3 +/- 3.1 mmol/l (p < 0.05, p < 0.01). CONCLUSIONS: 1.At presentation with PHPT, OGTT commonly identifies Type 2 DM and GI.2.After successful parathyroidectomy fasting and 2-h. PG fall significantly (p < 0.05, p < 0.01). DM and IGT/IFG often ameliorates to IGT or NGT, persistently.     

Concordance between fasting and 2-h post-glucose challenge criteria for the diagnosis of diabetes mellitus and glucose intolerance in high risk individuals.

AIMS: To compare the new fasting with the 2-h post glucose challenge diagnostic criteria for diabetes mellitus in a high-risk Central European population. METHODS: The results of the 75-g oral glucose tolerance tests (OGTT) performed between 1st January 1990 and 31st December 1998 in patients at high risk of glucose metabolism disturbance were analysed. RESULTS: From 1554 patients with OGTT results available for the study, 1360 (759 women and 601 men, aged 65.5+/-6.9 years, body mass index 28.2 +/- 4.5 kg/m2) were included into the study. With the use of the post-challenge criteria, 41.3% of the analysed population had diabetes or impaired diabetes tolerance (IGT), whereas with the new fasting system only 16.6% would have been diagnosed with any type of glucose intolerance. Diabetes was significantly more often diagnosed with the post-challenge criteria than with the fasting ones: 16.2 vs. 5.3% (P < 0.0001). The subjects with diabetes diagnosed upon fasting glucose value were significantly younger than the subjects with diabetes diagnosed according to the 2-h glucose challenge: 65.7 +/- 6.2 vs. 68.8 +/- 7.0 years, respectively (P < 0.01). The sensitivity of the new criteria for the diagnosis of diabetes was 18.2%, and specificity 97.2%. A total of 77.8% of IGT cases would have been diagnosed as having normal glucose metabolism according to the fasting glucose. The sensitivity of the new criteria for the diagnosis of impaired glucose tolerance (IGT or impaired fasting glucose) was 14.6%, and specificity 89.8%. The overall kappa statistic (k) was low; 0.211 (95% confidence interval 0.149-0.27). CONCLUSIONS: The new lower fasting criteria might be too insensitive to identify a large proportion of individuals with diabetes or impaired glucose intolerance, particularly in a high-risk population.     

Detection of impaired glucose tolerance and undiagnosed type 2 diabetes in UK South Asians: an effective screening strategy

Aim:  We tested a stepwise, community-based screening strategy for glucose intolerance in South Asians using a health questionnaire in conjunction with body mass index (BMI). Anthropometric measurements (waist and hip circumference, sagittal diameter and percentage body fat) were then conducted in a hospital setting followed by an oral glucose tolerance test (OGTT) to identify subjects at the highest risk and analyse the factors predicting that risk.
Methods:  A health questionnaire was administered to 435 subjects in a community setting and BMI was measured. Subjects were graded by a risk score based on the health questionnaire as high, medium and low. Subjects with high and medium risk scores and a representative sample of those with low scores had anthropometric measurements in hospital followed by an OGTT. In total, 205 (47%) of the subjects had an OGTT performed.
Results:  In total, 48.7% of the subjects tested with an OGTT had evidence of glucose dysregulation: 20% had diabetes and 28.7% had impaired glucose tolerance (IGT). Logistic regression model explained 49.1% of the total variability. The significant predictors of diabetes and IGT were Blood Glucose Monitoring Strips (BMI), random blood glucose (BM), sibling with diabetes and presence of diagnosed hypertension or ischaemic disease. Most of these predictors along with other heredity diabetes factors create a composite score, with high predictability, as the receiver operating curve analysis shows.
Conclusion:  We describe a simple, stepwise strategy in a community setting, based on a health questionnaire and anthropometric measurements, to explain about 50% of cases with IGT and diabetes and diagnose about 50% of cases from the population screened. We have also identified factors that predict the risk.     

不同糖耐量者血清游离脂肪酸与胰岛素抵抗的关系

以口服糖耐量试验(OGTT)确定受试者为正常人,糖耐量低减(IGT)和2型糖尿病,并测定空腹和OGTT 2h的游离脂肪酸(FFA)、血糖和胰岛素浓度,计算胰岛素敏感指数(IAI)。2型糖尿病和IGT患者的空腹和OGTT 2 h FFA、血糖和胰岛素浓度均明显高于正常组(均P<0.05),IAI均明显低于正常对照组(均P<0.01)。空腹及OGTT 2 h FFA与IAI之间呈显著负相关(分别为r=-0.38,P<0.01和r=-0.32,P<0.05),体重指数与IAI呈显著负相关(r=-0.39,P<0.05)。上述结果提示脂毒性在2型糖尿病的发病机制中有重要作用。     

Central rather than generalized obesity is related to hyperglycaemia in Asian Indian subjects.

The relationship of body mass index and waist-hip ratio with plasma glucose concentrations during an oral glucose tolerance test (OGTT) was studied in native Indian (Asian) subjects. A total of 389 subjects (131 non-diabetic, 74 impaired glucose tolerant (IGT) and 184 Type 2 diabetic (newly diagnosed and untreated] were studied. Prevalence of obesity (BMI greater than or equal to 27.0 kg m-2 in men and greater than or equal to 25.0 kg m-2 in women, 21% and 47%, respectively) was lower in people with Type 2 diabetes than that reported in white Caucasian and migrant Asian populations. Body mass index was highest in IGT subjects (26.1 (19.7-34.3) kg m-2, median (5-95th centile] and was higher in diabetic subjects (24.2 (19.3-32.2) kg m-2) than in non-diabetic control subjects (23.5 (17.1-30.0) kg m-2). However, waist-hip ratio was higher in both IGT (0.88 (0.75-0.98)) and diabetic subjects (0.88 (0.75-1.00)) than in non-diabetic control subjects (0.83 (0.70-0.97)), with no difference between the hyperglycaemic groups. On multivariate analysis, fasting as well as 2-h plasma glucose concentrations during OGTT were found to be related to waist-hip ratio (p less than 0.01) and subscapular fat thickness (p less than 0.01) but not to body mass index (or triceps fat thickness). Thus, in native Indians central obesity seems to be a more important association of hyperglycaemia than generalized obesity.     

脑梗死患者糖耐量减低与颈动脉粥样硬化的相关性研究

目的探讨脑梗死患者糖耐量减低(IGT)与颈动脉粥样硬化的关系。方法将120例急性脑梗死患者根据病史和口服葡萄糖耐量试验(OGTT)结果分为糖尿病(DM)组、IGT组、糖耐量正常组(NGT组)。对3组患者进行颈动脉超声检查,测定各组生化指标。结果与NGT组相比,IGT组和DM组的体重指数(BMI)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、空腹血糖(FPG)、餐后2h血糖(2hPG)、颈动脉内中膜厚度(CIMT)、斑块检出率及斑块积分均显著增高(P<0.05);Spearman相关性分析显示,CIMT与年龄、TC、LDL-C、2hPG呈正相关(P<0.05或P<0.01)。结论脑梗死患者在IGT阶段已经发生颈动脉粥样硬化改变,早期控制血糖,可减轻脑血管病变的严重程度、减少血管事件发生。     

Insulin resistance and impaired glucose tolerance in obese children and adolescents referred to a tertiary-care center in Israel

OBJECTIVE: To establish the prevalence of insulin resistance and impaired glucose tolerance (IGT) and their determinants in a cohort of obese children and adolescents. METHODS: A retrospective design was used. The study group included 234 patients with a body mass index (BMI) greater than the 95th percentile for age and gender and 22 patients with a BMI between the 85th and 95th percentile for age and gender referred for evaluation to a major tertiary-care center in Israel. Ages ranged from 5 to 22 y. Estimates of insulin resistance (homeostatic model assessment (HOMA-IR)); insulin sensitivity (ratio of fasting glucose (GF) to fasting insulin (IF) (GF/IF), the quantitative insulin sensitivity check index (QUICKI)), and pancreatic beta-cell function (HOMA-derived beta-cell function (HOMA %B)) were derived from fasting measurements. An oral glucose tolerance test (OGTT) was performed in 192 patients to determine the presence of IGT. RESULTS: Insulin resistance was detected in 81.2% of the patients, IGT in 13.5%, and silent diabetes in one adolescent girl. Only two patients with IGT also had impaired fasting glucose (IFG). The prevalence of IGT was higher in adolescents than prepubertal children (14.7 vs 8.6%). GF/IF and QUICKI decreased significantly during puberty (P<0.005), whereas HOMA-IR and HOMA %B did not. Insulin resistance and insulin sensitivity indexes were not associated with ethnicity, presence of acanthosis nigricans or family history of type 2 diabetes. Patients with obesity complications had lower insulin sensitivity indexes than those without (P=0.05). Compared with subjects with normal glucose tolerance (NGT), patients with IGT had significantly higher fasting blood glucose (85.9+/-6.5 vs 89.2+/-10.6 mg/dl, P<0.05), higher 2-h post-OGGT insulin levels (101.2+/-74.0 vs 207.6+/-129.7 microU/ml, P<0.001), a lower QUICKI (0.323+/-0.031 vs 0.309+/-0.022, P<0.05), and higher fasting triglyceride levels (117.4+/-53.1 vs 156.9+/-68.9, P=0.002). However, several of the fasting indexes except QUICKI failed to predict IGT. There was no difference between the group with IGT and the group with NGT in fasting insulin, HOMA-IR, HOMA %B or the male-to-female ratio, age, BMI-SDS, presence of acanthosis nigricans, ethnicity, and family history of type 2 diabetes.CONCLUSIONS:Insulin resistance is highly prevalent in obese children and adolescents. The onset of IGT is associated with the development of severe hyperinsulinemia as there are no predictive cutpoint values of insulin resistance or insulin sensitivity indexes for IGT, and neither fasting blood glucose nor insulin levels nor HOMA-IR or HOMA %B are effective screening tools; an OGTT is required in all subjects at high risk. Longitudinal studies are needed to identify the metabolic precursors and the natural history of the development of type 2 diabetes in these patients.     

Fasting proinsulin and 2-h post-load glucose levels predict the conversion to NIDDM in subjects with impaired glucose tolerance: The Hoorn Study

Summary The aims of the present study were to observe the natural history of impaired glucose tolerance and to identify predictors for development of non-insulin-dependent diabetes mellitus (NIDDM). A survey of glucose tolerance was conducted in subjects aged 50–74 years, randomly selected from the registry of the middle-sized town of Hoorn in the Netherlands. Based on the mean values of two oral glucose tolerance tests subjects were classified in categories of glucose tolerance according to the World Health Organization criteria. All subjects with impaired glucose tolerance (n=224) were invited to participate in the present study, in which 70% (n=158) were subsequently enrolled. During follow-up subjects underwent a repeated paired oral glucose tolerance test. The mean follow-up time was 24 months (range 12–36 months). The cumulative incidence of NIDDM was 28.5% (95% confidence interval 15–42%). Age, sex, and anthropometric and metabolic characteristics at baseline were analysed simultaneously as potential predictors of conversion to NIDDM using multiple logistic regression. The initial 2-h post-load plasma glucose levels and the fasting proinsulin levels were significantly (p<0.05) related to the incidence of NIDDM. Anthropometric characteristics, the 2-h post-load specific insulin levels and the fasting proinsulin/fasting insulin ratio were not related to the incidence of NIDDM. These results suggest that beta-cell dysfunction rather than insulin resistance plays the most important role in the future development of diabetes in a high-risk Caucasian population.Abbreviations IGT Impaired glucose tolerance - NIDDM non-insulin-dependent diabetes mellitus - OGTT oral glucose tolerance test - CI confidence interval - W/H ratio waist/hip ratio - BMI body mass index - OR odds ratio     

The abbreviated glucose tolerance test in screening for diabetes: the Islington Diabetes Survey

The World Health Organization has recommended a single 2-h post-glucose load blood glucose level as a screening test for diabetes mellitus in epidemiological surveys. We have assessed its characteristics, when compared with a full supervised glucose tolerance test (OGTT), in estimating prevalence, and in diagnosing diabetes in the individual patient. A stratified sample of 223 of 1040 subjects who had participated in a diabetic survey that utilized a single capillary 2-h blood glucose estimation as a screening test were recalled for formal glucose tolerance testing. The numbers of subjects with diabetes at screening and at recall were similar (14/212, 6.6%; 13/216, 6.0%) but only 9 subjects were so classified on both occasions. Thirty-five subjects (16.5%) were suspected of having impaired glucose tolerance (IGT) at screening, and 52 (24.1%) at recall. There was substantial reclassification from screening IGT, with 3/35 worsening to diabetes, and 10/35 returning to normal. Capillary 2-h glucose levels gave an accurate assessment of the prevalence of diabetes but underestimated that of IGT. On the full OGTT, little difference in classification was found when the values of fasting and 1-h blood glucose were used in addition to those of the 2-h blood glucose used alone. The 2-h glucose had a within-subject coefficient of variation of 32.4% which produced substantial reclassification of subjects with levels close to the diagnostic levels for diabetes, and this implies that such individuals should not be classified as having diabetes on the basis of a single glucose tolerance test.(ABSTRACT TRUNCATED AT 250 WORDS)     

Screening for Diabetes: Does Measurement of Serum Fructosamine Help?

The diagnostic sensitivity and specificity for diabetes of serum fructosamine levels and fasting venous blood glucose concentrations were compared in 613 subjects during a diabetes community screening programme of 1049 adult Muslim Asians in Dar es Salaam, Tanzania. Using WHO (1985) criteria 228 had impaired glucose tolerance (IGT), 41 had previously been diagnosed as having diabetes while 32 had newly recognized diabetes. The mean (+/- SD) serum fructosamine levels were 20.9 +/- 3.2, 21.6 +/- 3.2, 23.9 +/- 4.9, and 30.1 +/- 7.9 (mumol g-1 albumin) in subjects with normal glucose tolerance, IGT, newly diagnosed diabetes, and previously diagnosed diabetes, respectively (p less than 0.001 for differences between groups). The specificity of values above the mean +2SD normal was 99% for abnormal glucose tolerance with a sensitivity of only 22% for diabetes. The predictive values were 44% and 97% for positive and negative results, respectively. Very little difference from normal was found for IGT subjects. Expressing fructosamine values in absolute terms or per gram albumin made little difference to sensitivity and specificity. The sensitivity was only 32% for fasting blood glucose greater than or equal to 6.7 mmol l-1, 73% for values greater than or equal to 5.5 mmol l-1, and 100% for fasting blood glucose greater than or equal to 4.5 mmol l-1. It is concluded that both serum fructosamine and fasting blood glucose are poor screening and diagnostic tests for diabetes and for IGT, and that glucose loading is required.     

Pancreatic B-cell function is altered by oxidative stress induced by acute hyperglycaemia.

AIMS: Type 2 diabetes is preceded by a symptom-free period of impaired glucose tolerance (IGT). Pancreatic B-cell function decreases as glucose intolerance develops. In many patients with IGT, fasting blood glucose is within normal limits and hyperglycaemia occurs only postprandially. We examined whether pancreatic B-cell function changes during acute hyperglycaemia induced by oral glucose loading. METHODS: We calculated the insulinogenic index (I.I.) as an indicator of pancreatic B-cell function and measured serum levels of thioredoxin, a marker of cellular redox state, and 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker of oxidative stress, during a 75-g oral glucose tolerance test (OGTT) in 45 subjects [24 patients with normal glucose tolerance (NGT), 14 with IGT and seven with Type 2 diabetes]. RESULTS: Thioredoxin levels decreased after glucose loading [66.1 +/- 23.7, *59.3 +/- 22.4, *49.3 +/- 21.2 and *37.7 +/- 18.0 ng/ml, fasting (0 min) and at 30, 60 and 120 min, respectively; *P < 0.001 vs. fasting]. In contrast, concentrations of 8-OHdG peaked at 30 min and then gradually decreased (0.402 +/- 0.123, *0.440 +/- 0.120, 0.362 +/- 0.119 and 0.355 +/- 0.131 ng/ml, *P < 0.05 vs. fasting, P < 0.01 vs. 30 min). The insulinogenic index correlated with the change in thioredoxin levels (r = 0.34, P < 0.05). However, there was no relationship with the change in 8-OHdG levels from 0 to 30 min. CONCLUSIONS: Hyperglycaemia in response to oral glucose impairs pancreatic B-cell function with decreasing thioredoxin levels. The augmented oxidative stress induced by hyperglycaemia may affect the cellular redox state. These findings strongly suggest that repeated postprandial hyperglycaemia may play an important role in the development and progression of diabetes mellitus.     

糖尿病前期尿白蛋白排泄率和微量白蛋白尿患病率的比较

目的　比较糖耐量正常 (NGT)、单纯空腹血糖受损 (I IFG)、单纯糖耐量低减 (I IGT)、糖耐量低减合并空腹血糖受损 (IGT/IFG)、新诊断的 2型糖尿病 (2型DM ) 5种不同糖代谢状态的尿白蛋白排泄率 (UAE)和微量白蛋白尿 (MAU )患病率。方法　根据 75g口服葡萄糖耐量试验 (75gOGTT)结果 ,将 2 93 4例受试者分为 :NGT组 13 3 2例、I IFG组 186例、I IGT组 470例、IGT/IFG组 2 3 6例、新诊断的 2型DM组 710例。用放射免疫法测定过夜 12h尿白蛋白。UAE在 2 0～ 2 0 0μg/min之间定义为MAU。 结果　 (1)UAE水平 [中位数 (四分位数 ) ] ,在新诊断的 2型DM组为8 50 (4 89～ 15 95) μg/min、IGT/IFG组为 6 93 (4 85～ 10 89) μg/min、I IGT组为 6 51(4 0 9～10 74) μg/min ,均高于I IFG组的 5 56(3 70～ 9 2 3 ) μg/min(P值均 <0 0 1) ;I IFG组与NGT组的 5 2 6(3 50～ 8 12 ) μg/min比较差异无显著性 (P >0 0 5) ;MAU的患病率在新诊断的 2型DM组为 2 0 7%、IGT/IFG组为 13 1%、I IGT组为 11 7%、I IFG组为 5 8%、NGT组为 5 6% ,同样呈现上述变化规律。(2 )多元逐步回归分析显示 :UAE与OGTT 2h血糖、舒张压、体重指数呈现独立正相关。logistic回归分析显示 ,导致MAU危险性增加的因素有OGTT 2h血糖、舒张     

Metabolic effects of metformin in patients with impaired glucose tolerance.

AIMS: To assess the effect of metformin on insulin sensitivity, glucose tolerance and components of the metabolic syndrome in patients with impaired glucose tolerance (IGT). METHODS: Forty first-degree relatives of patients with Type 2 diabetes fulfilling WHO criteria for IGT and participating in the Botnia study in Finland were randomized to treatment with either metformin 500 mg b.i.d. or placebo for 6 months. An oral glucose tolerance test (OGTT) and a euglycaemic hyperinsulinaemic clamp in combination with indirect calorimetry was performed at 0 and 6 months. The patients were followed after stopping treatment for another 6 months in an open trial and a repeat OGTT was performed at 12 months. RESULTS: Metformin treatment resulted in a 20% improvement in insulin-stimulated glucose metabolism (from 28.7 +/- 13 to 34.4 +/- 10.7 micromol/kg fat-free mass (FFM)/min) compared with placebo (P = 0.01), which was primarily due to an increase in glucose oxidation (from 16.6 +/- 3.6 to 19.1 +/- 4.4 micromol/kg FFM; P = 0.03) These changes were associated with a minimal improvement in glucose tolerance, which was maintained after 12 months. CONCLUSIONS: Metformin improves insulin sensitivity in subjects with IGT primarily by reversal of the glucose fatty acid cycle. Obviously large multicentre studies are needed to establish whether these effects are sufficient to prevent progression to manifest Type 2 diabetes and associated cardiovascular morbidity and mortality. Diabet. Med. 18, 578-583 (2001)     

Long-term beneficial effects of glipizide treatment on glucose tolerance in subjects with impaired glucose tolerance

AIMS: To assess the efficacy and long-term effects of glipizide treatment on glucose and insulin metabolism in individuals with impaired glucose tolerance (IGT). METHODS: Thirty-seven first-degree relatives of patients with type 2 diabetes fulfilling WHO criteria for IGT were randomized to treatment with either glipizide 2.5 mg once daily or matching placebo for 6 months. A 75 g, 2-h oral (OGTT) and 60 min intravenous glucose tolerance test (IVGTT) were performed at baseline and after 6 months. The subjects were followed up for another 12 months after discontinuation of treatment and a repeat OGTT was performed at 18 months. RESULTS: Thirty-three subjects fulfilled the study. Markers of insulin sensitivity - i.e. fasting insulin and HOMA(IR)-index - improved in the glipizide group (P = 0.04 and 0.02 respectively) as well as HDL cholesterol (P = 0.05) compared with placebo group after 6 months. At 18 months, both fasting and 2 h glucose concentrations were significantly lower in the glipizide group compared with the placebo group (P = 0.04 and 0.03 respectively). The prevalence of type 2 diabetes was 29.4% in the placebo group and 5.9% in the glipizide group at 18 months. This equals an 80% relative risk reduction in the active treatment group. CONCLUSIONS: Short-term treatment with glipizide improves glucose and insulin metabolism in subjects with IGT primarily by improving insulin sensitivity mediated by lowering glucose toxicity, thereby providing the beta cells rest. Larger studies are needed to establish whether these effects are sufficient to prevent progression to manifest type 2 diabetes and associated cardiovascular morbidity in subjects at increased risk of developing type 2 diabetes.     

The value of glycosylated haemoglobin as a substitute for the oral glucose tolerance test in the detection of impaired glucose tolerance (IGT).

In a prospective study of South African Indian subjects with IGT, glycosylated hemoglobin [specifically HbA1 (HbA1(a+b+c)] and its relationship to the oral glucose tolerance test (OGTT) was studied in 128 study subjects who were classified IGT a year previously (Year 0 of study) and in 64 control subjects. At Year 1 of the study, the standard 75-g OGTT was performed on all subjects; study subjects were further divided into three groups based on World Health Organisation criteria [Normal (N), impaired glucose tolerance (IGT), diabetes mellitus (D)]. HbA1, a glycosylated hemoglobin (GHb), was measured by a cation-exchange microchromatographic method. Based on OGTT results, 47 of the 128 study subjects were classified IGT, 41 diabetes (newly-diagnosed diabetes) and 40 subjects had normal glucose tolerance. Mean GHb was significantly higher in the D group (7.61 +/- 1.76%) compared to the control group (6.99 +/- 1.22%) and the N group (6.9 +/- 1.12%), respectively (P less than 0.05); there was no significant difference between the IGT group (7.48 +/- 1.44%) and each of the other three groups. Compared to the OGTT, GHb was relatively insensitive in the diagnosis of IGT or diabetes mellitus: only 17% of the IGT group and 26.8% of the D group has elevated GHb values; the specificity of GHb as a measure of normal glucose tolerance was 85.9%. The majority of subjects, irrespective of the category of glucose tolerance, had GHb levels within the normal range and there was marked overlap between the four groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

生活方式干预对糖耐量异常者动脉内膜厚度及弹性的影响

目的探讨饮食、运动等生活方式干预对糖耐量异常者颈动脉内膜中膜厚度与臂踝脉搏波传导速度的影响。方法收集糖耐量异常者162例,随机分为78例对照组,84例干预组;对照组给予每3个月1次的糖尿病健康知识宣教(电话),干预组在此基础上进行为期24个月的生活方式干预,并每月随访1次。每例均采用超声及全自动动脉硬化仪测定颈动脉内膜中膜厚度与臂踝脉搏波传导速度。各组均进行前后自身对照和组间对照,并评价干预效果。结果经过24个月生活方式干预,干预组糖尿病累计发病率较对照组显著下降;干预组较干预前甘油三酯、口服糖耐量试验2 h血糖显著降低(P<0.05),其余指标经对比后差异无统计学意义;干预组与对照组比较,两组颈动脉内膜中膜厚度有显著性差异(P<0.05),除臂踝脉搏波传导速度、体质指数、高密度脂蛋白外,其余各项指标均有显著改善(P<0.05或P<0.01)。结论生活方式干预能有效改善糖耐量异常患者的代谢状态,降低糖尿病发病率,并能延缓其血管病变的发展;强化生活方式干预应在糖耐量异常人群中大力推行。