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.     

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.     

空腹血糖异常、糖耐量减低患者血清胰岛素水平的变化及其意义

目的 观察空腹血糖异常(IFG)、糖耐量减低(IGT)患者血清胰岛素水平的变化。方法 对50例空腹血糖和糖耐量正常者(NGT)、40例IFC和80例IGT患者行口服葡萄糖耐量试验(0GTT)，用氧化酶法检测血糖，用放免法测定血清空腹及餐后2小时胰岛素。结果 IFG、IGT组空腹血糖、空腹胰岛素水平及胰岛素敏感指数较NGT组明显升高(P＜0.05或P＜0．01)，IFG组胰岛素敏感指数与IGT组比较无显著性差异(P＞0．05)。结论 在IFG、IGT状态下已经存在胰岛素抵抗，而且在程度上两者间并没有显著性差异，应早期干预治疗。     

Insulin secretion and insulin sensitivity in Japanese subjects with impaired fasting glucose and isolated fasting hyperglycemia

Impaired fasting glucose (IFG) is a subgroup of impaired glucose regulation exhibiting an elevated fasting glucose levels without elevated 2-h glucose levels on oral glucose tolerance test (OGTT). Diabetes mellitus with isolated fasting hyperglycemia (DM/IFH) is a similar subgroup of diabetes having higher fasting glucose levels with 2-h glucose levels within the non-diabetic range. The aim of this study is to profile the characteristics of these subgroups to estimate the factors involved in the development from normal glucose tolerance (NGT) via IFG to DM/IFH. Five hundred and sixty seven Japanese males were classified on the basis of 75 g OGTT into four groups, NGT, IFG, DM/IFH, and isolated impaired glucose tolerance (isolated IGT). Insulin secretion was evaluated by insulinogenic index, insulin sensitivity was evaluated by ISI composite, and insulin secretory patterns were compared additionally. IFG and DM/IFH subjects exhibited both lower insulin secretion and lower insulin sensitivity than NGT subjects. There was an insulin peak in NGT, IFG, and DM/IFH at 60 min, which did not occur in isolated IGT. Impaired early-phase and basal insulin secretion and decreased insulin sensitivity both are estimated as factors in progression from NGT via IFG to DM/IFH in these subjects. IFG and DM/IFH subjects have definite fasting hyperglycemia in contrast to isolated IGT subjects, 2-h glucose levels being maintained within the non-diabetic range partly by the insulin peak at 60 min.     

Effects of rosglitazone on plasma adiponectin, insulin sensitivity, and insulin secretion in high-risk African Americans with impaired glucose tolerance test and type 2 diabetes

We examined the metabolic effects of rosiglitazone therapy on glucose control, insulin sensitivity, insulin secretion, and adiponectin in first-degree relatives of African Americans with type 2 diabetes (DM) with impaired glucose tolerance (IGT) and DM for 3 months. The study was comprised of 12 first-degree relatives with IGT, 17 newly diagnosed DM, and 19 healthy relatives with normal glucose tolerance (NGT). Oral glucose tolerance test (OGTT) was performed before and after 3 months of rosiglitazone therapy (4 to 8 mg/d) in patients with IGT and DM. Serum glucose, insulin, C-peptide, and adiponectin levels were measured before and 2 hours during OGTT in the NGT and patients with IGT and DM. Insulin resistance index (HOMA-IR) and beta-cell function (HOMA-%B) were calculated in each subject using homeostasis model assessment (HOMA). Rosglitazone improved the overall glycemic control in the IGT and DM groups. Following rosiglitazone, the beta-cell secretion remained unchanged, while HOMR-IR was reduced in DM by 30% (4.12 +/- 1.95 v 6.33 +/- 3.54, P < .05) and the IGT group (3.78 +/- 2.45 v 4.81 +/- 3.49, P = not significant [NS]). Mean plasma adiponectin levels were significantly (P < .05) lower in the DM (6.74 +/- 1.95 microg/mL) when compared with the NGT group(9.61 +/- 5.09). Rosiglitazone significantly (P < .001) increased adiponectin levels by 2-fold in patients with IGT (22.2 +/- 10.97 microg/mL) and 2.5-fold greater in DM (15.68 +/- 8.23 microg/mL) at 3 months when compared with the 0 month. We conclude that adiponectin could play a significant role (1) in the pathogenesis of IGT and DM and (2) the beneficial metabolic effects of thiazolidinediones (TZDs) in high-risk African American patients.     

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.     

Adipocytes in subjects with impaired fasting glucose and impaired glucose tolerance are resistant to the anti-lipolytic effect of insulin

Impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) are two intermediate states in the transition from normal glucose metabolism to type 2 diabetes. Insulin clamp studies have shown that subjects with IGT have increased insulin resistance in skeletal muscle, while subjects with IFG have near normal muscle insulin sensitivity. Because of the central role of altered free fatty acid (FFA) metabolism in the pathogenesis of insulin resistance, we have examined plasma free fatty acid concentration under fasting conditions, and during OGTT in subjects with IGT and IFG. Seventy-one NGT, 70 IGT and 46 IFG subjects were studied. Fasting plasma FFA in IGT subjects was significantly greater than NGT, while subjects with IFG had similar fasting plasma FFA concentration to NGT. However, fasting plasma insulin concentration was significantly increased in IFG subjects compared to NGT while subjects with IGT had near normal fasting plasma insulin levels. The adipocyte insulin resistance index (product of fasting plasma FFA and FPI) was significantly increased in both IFG and IGT subjects compared to NGT. During the OGTT both IFG and IGT subjects suppressed their plasma FFA concentration similarly to NGT subjects, but the post-glucose loads were significantly increased in both IFG and IGT subjects. These data suggest that both subjects with IFG and IGT have increased resistance to the antilipolytic action of insulin. However, under basal conditions, fasting hyperinsulinemia in IFG subjects is sufficient to offset the adipocyte insulin resistance and maintain normal fasting plasma FFA concentration while the lack of increase in FPI in IGT subjects results in an elevated fasting plasma FFA.     

Early insulin secretion failure leads to diabetes in Chinese subjects with impaired glucose regulation

Background Both beta‐cell dysfunction and decreased insulin sensitivity are involved in the pathogenesis of impaired glucose tolerance (IGT) and impaired fasting glucose (IFG), while their relative contribution in the progression to type 2 diabetes still remains controversial. The aim of the present study is to clarify this process in Chinese subjects by using cross‐sectional method. Methods 2975 Chinese subjects were classified into: normal glucose tolerance (NGT), impaired glucose regulations (IGR), and diabetes mellitus (DM) based on oral glucose tolerance test (OGTT). The IGR group was sub‐classified as isolated IFG, isolated IGT and combined glucose intolerance (CGI). The DM group was sub‐classified as normal fasting plasma glucose and 2‐hour hyperglycemia (N0D2), fasting hyperglycemia and normal 2‐hour plasma glucose (D0N2), and both fasting and 2‐hour hyperglycemia (D0D2). Results As far as insulinogenic index (IGI) was concerned, there was no difference between IFG and IGT in either gender, however, HOMA2‐B% (homeostasis model assessment for beta‐cell function) of IGT was higher than that of IFG and CGI in both male and female (P < 0.05). In the diabetic sub‐groups, IGI of N0D2 was higher than that of D0N2, and both deteriorated compared with those of IGT and IFG, respectively. HOMA2‐B% of N0D2 was still higher than that of D0N2 and D0D2. No significant difference was detected in OGIS and HOMA2‐S% (homeostasis model assessment for insulin sensitivity) between IFG and IGT, and this was the case between N0D2 and D0N2. OGIS and HOMA‐IR of IGR sub‐groups were not different from those of their diabetic counterparts. Conclusion Failure of beta‐cell function might be the main reason for both IGT and IFG developing into diabetes instead of aggravated insulin resistance. Copyright © 2008 John Wiley & Sons, Ltd.     

不同状态的糖调节受损患者胰岛素分泌和胰岛素敏感性的差异

目的评估初发的单纯空腹血糖受损（IFG）和单纯糖耐量受损（IGT）患者的胰岛素分泌以及胰岛素敏感性（IS）特征。方法北京市东城区既往无糖尿病史的2388名受试者行葡萄糖耐量试验,同时行胰岛素释放试验,本文纳入2244例,其中糖耐量正常（NGT）1608例,IFG240例,IGT243例,IFG＋IGT 153例。比较各组胰岛素抵抗指数（HOMA-IR）、IS指数（Matsudaindex）、B细胞功能指数（1相Stumvoll index、△I30／△G30）。结果与NGT组比较,其余三组HOMA-IR显著升高,Matsuda指数及B细胞功能指数均显著降低（P均〈0．01）;IFG组HOMA-IR及Matsuda指数均高于IGT组;IFG组△I30／△G30高于IGT组,而Stumvoll指数低于IGT组（P〈0．01）;与IFG组、IGT组比较,IFG＋IGT组HOMA-IR显著升高,Matsuda指数、1相Stumvoll指数显著降低（P均〈0．01）。结论糖尿病前期人群存在不同程度的胰岛素分泌缺陷和IR,IFG组肝IR较重,而IGT组肌肉IR较重。     

Epidemiological evidence of altered cardiac autonomic function in subjects with impaired glucose tolerance but not isolated impaired fasting glucose

CONTEXT: Autonomic dysfunction is present in diabetes mellitus (DM), but no study is available on alteration in cardiac autonomic function (CAF) across different glycemic statuses including normal glucose tolerance (NGT), isolated impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and DM. OBJECTIVE: Our objective was to examine whether CAF is altered in subjects with IGT and isolated IFG. DESIGN AND SETTING: The study was a stratified systematic cluster sampling design within the general community. PARTICIPANTS: A total of 1440 subjects were classified as NGT (n = 983), isolated IFG (n = 163), IGT (n = 188), and DM (n = 106). MAIN OUTCOME MEASURE: CAF was determined by 1) standard deviation of normal-to-normal (SDNN) or RR interval, power spectrum in low and high frequency (LF, 0.04-0.15 Hz; HF, 0.15-0.40 Hz), and LF/HF ratio in supine position for 5 min; 2) ratio between 30th and 15th RR interval after standing from supine position (30/15 ratio); and 3) average heart rate change during breathing of six deep breaths for 1 min (HR(DB)). RESULTS: Univariate analysis showed significant differences in SDNN, 30/15 ratio, HR(DB), HF power, and LF/HF ratio among subjects with NGT, isolated IFG, IGT, and DM. In multivariate analysis, none of the indices of CAF was related to isolated IFG in the reference group of NGT. IGT and DM were negatively associated with 30/15 ratio and HF power but positively associated with LF/HF ratio. In addition, DM was also related to a lower SDNN. CONCLUSIONS: DM and IGT subjects had an impaired CAF independent of other cardiovascular risk factors. The risk of altered CAF is not apparent in subjects with isolated IFG.     

Prevalence and characteristics of impaired glucose metabolism in patients referred to comprehensive cardiac rehabilitation: the DANSUK study.

BACKGROUND: Lifestyle and pharmacological interventions can delay the progression of impaired glucose tolerance (IGT) to type 2 diabetes (T2DM), and there is growing evidence that earlier detection of T2DM and intensified risk factor management may result in improved cardiovascular morbidity and mortality. We studied the prevalence of impaired glucose metabolism (T2DM, IGT and impaired fasting glucose; IFG) in patients referred to cardiac rehabilitation, and further studied whether we could identify groups in which an oral glucose tolerance test (OGTT) need not be performed. METHODS: As part of a cardiac rehabilitation trial, 201 patients participated. Patients without a diagnosis of T2DM (N=159) underwent an OGTT 3 months after inclusion. RESULTS: Forty-two patients (21%) had known T2DM at enrolment. Based on the OGTT, 26 patients (13%) had unrecognized T2DM, 36 (18%) had IGT and 19 (9%) were diagnosed with isolated IFG according to the World Health Organization definition. Using fasting plasma glucose alone, 19% of the patients with unrecognized T2DM and two-thirds of patients with IGT would be misclassified. Using IFG as a means to detect IGT showed a sensitivity of only 33% and a positive predictive value of 39%. CONCLUSION: More than 60% of the patients (123/201) referred to cardiac rehabilitation had impaired glucose metabolism and 18% of the screened patients (29/159) would be misclassified if an OGTT was omitted. IFG and IGT did not identify the same patients or the same cardiovascular risk profile. An OGTT test should therefore be considered a constituent part of routine care management in cardiac rehabilitation settings.     

空腹血糖受损与糖耐量受损患者血管内皮功能的对比研究

目的:应用多普勒超声技术检测空腹血糖受损(IFG)与糖耐量受损(IGT)患者的血管内皮功能,探讨其对动脉粥样硬化的影响。方法:根据口服葡萄糖耐量试验(OGTT)结果,选择血糖正常(NGT)组25例,IFG组24例,IGT组22例,检测TC、TG、LDL-C、HDL-C、空腹血糖(FPG)、空腹胰岛素(FINS)、糖化血红蛋白(HbA1C)、高敏C反应蛋白(hs-CRP)及血管性血友病因子(vWF),OGTT后2h血糖(2hPG)及2h胰岛素(2hINS),以及肱动脉内皮依赖性舒张功能(EDD)。结果:IGT组vWF较IFG组、NGT组明显升高[(170.25±21.76)%∶(155.16±17.19)%、(135.46±15.52)%,P<0.05～0.01],肱动脉EDD较IFG组、NGT组明显降低[(4.86±0.94)%∶(5.47±0.90)%、(6.24±0.97)%,P<0.05～0.01];IFG组vWF较NGT组明显升高[(155.16±17.19)%∶(135.46±15.52)%,P<0.05],肱动脉EDD较NGT组明显降低[(5.47±0.90)%∶(6.24±0.97)%,P<0.05]。多因素逐步回归分析显示,EDD与2hPG、LDL-C明显负相关(r分别为-0.73、-0.59,P<0.05)。结论:IGT较IFG对血管内皮功能危害更大,加强IGT防治对延缓动脉粥样硬化更为重要。     

Thiazolidinediones increase hepatic insulin extraction in African Americans with impaired glucose tolerance and type 2 diabetes mellitus. A pilot study of rosiglitazone

Peripheral insulin levels are determined by beta-cell secretion, insulin sensitivity, and hepatic insulin extraction (HIE). We have previously shown that whereas sulfonylureas reduce insulin extraction, metformin enhances HIE. However, the effects of thiazolidinediones (TZDs) on HIE remain uncertain. Thus, we investigated the potential contribution of hepatic insulin clearance to peripheral insulin levels during rosiglitazone therapy in African Americans with impaired glucose tolerance (IGT) and type 2 diabetes mellitus (DM). The study was composed of 12 first-degree relatives with IGT and 17 patients with newly diagnosed type 2 DM. Nineteen healthy relatives with normal glucose tolerance served as controls. Serum glucose, insulin, and C-peptide, and HIE (C-peptide-insulin molar ratios) were measured at t = 0 and 120 minutes during oral glucose tolerance test (OGTT) in all the subjects. The OGTT was performed before and after 3 months of rosiglitazone therapy (4 mg/d x 4 weeks and >8 mg/d x 8 weeks) in patients with IGT and type 2 DM. Insulin resistance index and beta-cell function were calculated in each subject using homeostasis model assessment (HOMA). Rosiglitazone therapy improved but did not normalize the overall glycemic control in the IGT and type 2 DM groups. After rosiglitazone therapy, the mean serum insulin and C-peptide levels at fasting remained unchanged. However, the 2-hour serum glucose and insulin were lower, whereas serum C-peptide was unchanged during 3 months of rosiglitazone treatment. Mean insulin resistance index of HOMA was reduced by 30% (4.12 +/- 1.95 vs 6.33 +/- 3.54, P < .05) in the type 2 DM group and by 21% (3.78 +/- 2.45 vs 4.81 +/- 3.49, P = NS) in the IGT group. Mean HIE values were significantly lower (70%) in the type 2 DM and IGT groups when compared with the normal glucose tolerance group. At 3 months, basal HIE was not significantly changed by rosiglitazone therapy in IGT and type 2 DM groups when compared with the baseline (0 month). However, rosiglitazone therapy was associated with increased HIE at 2 hours during OGTT by 40% and 30% in the IGT and type 2 DM groups, respectively, from the baseline (0 month) values. Furthermore, HIE inversely correlated with the insulin resistance index of HOMA (r = -.46, P < .05). We conclude that rosiglitazone therapy improved overall glucose tolerance and enhanced insulin sensitivity in patients with IGT and type 2 DM. Although basal HIE remained unchanged, rosiglitazone therapy increased postglucose challenge HIE in African Americans with IGT and type 2 DM. We speculate that TZDs increase insulin clearance or HIE after oral glucose challenge. This study suggests that in addition to insulin sensitization, rosiglitazone may be involved in insulin metabolism. The significance of the increased insulin clearance by TZD therapy remains uncertain and deserves further investigation in patients with insulin resistance and glucose intolerance.     

新疆汉、维民族糖调节受损人群胰岛素分泌功能和胰岛素作用功能的研究

目的 评估新疆汉、维民族在IFG,IGT及IGR阶段的胰岛素分泌功能和胰岛素作用功能。 方法 采用多中心研究进行横断面调查,行OGTT试验。用胰岛素抵抗指数（HOMA-IR）评估IR,胰岛β细胞功能指数（HOMA-β）评估基础胰岛素分泌;ΔI30/ΔG30评价胰岛素早相分泌,ΔI30/ΔG30/HOMA-IR评估葡萄糖处置指数（DI）。 结果 WC、BMI、血脂、FIns、2 hIns在汉、维民族不同糖代谢组差异有统计学意义。IFG组与NGT、IGT组比较,汉、维族人群的HOMA-IR差异有统计学意义。在汉族中NGT组与IGT、IGR组比较,HOMA-β差异有统计学意义（P=0.030、0.044）,而在维族只有IFG组与NGT组比较差异有统计学意义（P=0.001）。ΔI30/ΔG30、DI在两民族不同糖代谢组差异均无统计学意义。 结论 汉族人群IR在IFG阶段,胰岛素分泌功能在IGT阶段起主要作用。IR和胰岛素分泌功能在维族人群IFG阶段起重要作用。胰岛素早相分泌及葡萄糖处置功能在糖调节受损阶段作用不显著。     

Pancreatic iron and glucose dysregulation in thalassemia major

Pancreatic iron overload and diabetes mellitus (DM) are common in thalassemia major patients. However, the relationship between iron stores and glucose disturbances is not well defined. We used a frequently sampled oral glucose tolerance test (OGTT), coupled with mathematical modeling, and magnetic resonance imaging (MRI) to examine the impact of pancreatic, cardiac, and hepatic iron overload on glucose regulation in 59 patients with thalassemia major. According to OGTT results, 11 patients had DM, 12 had impaired glucose tolerance (IGT), 8 had isolated impaired fasting glucose (IFG), and 28 patients had normal glucose tolerance (NGT). Patients with DM had significantly impaired insulin sensitivity and insulin release. Insulin resistance was most strongly associated with markers of inflammation and somatic iron overload, while disposition index (DI) (a measure of beta cell function) was most strongly correlated with pancreas R2*. Patients with DM and IGT had significantly worse DI than those with NGT or IFG, suggesting significant beta cell toxicity. One‐third of patients having elevated pancreas R2* had normal glucose regulation (preclinical iron burden), but these patients were younger and had lower hepatic iron burdens. Our study indicates that pancreatic iron is the strongest predictor of beta cell toxicity, but total body iron burden, age, and body habitus also influence glucose regulation. We also demonstrate that MRI and fasting glucose/insulin are complementary screening tools, reducing the need for oral glucose tolerance testing, and identify high‐risk patients before irreversible pancreatic damage. Am. J. Hematol., 2011. © 2011 Wiley Periodicals, Inc.     

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     

Relationship between insulin resistance and left ventricular diastolic dysfunction in patients with impaired glucose tolerance and type 2 diabetes

AIM: The aim of this study was to explore the relationship between insulin resistance (IR) and the left ventricular diastolic function in patients with type 2 diabetes and subjects with impaired glucose tolerance (IGT). METHODS: The study included 119 subjects who underwent oral glucose tolerance test (OGTT). IR was assessed using Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) and Quantitative Insulin Sensitivity Check Index (QUICKI). Left ventricular diastolic function was assessed using trans-thoracic Doppler echocardiography. RESULTS: Based on the OGTT results, 29 subjects had normal glucose tolerance (NGT), 20 subjects had impaired glucose tolerance (IGT), and 70 patients had type 2 diabetes. There were significant differences among the patients in groups with NGT, IGT and diabetes regarding HOMA-IR (4.20 +/- 1.20 vs. 6.45 +/- 3.83 vs. 8.70 +/- 6.26; P < 0.001) and QUICKI (0.54 +/- 0.11 vs. 0.49 +/- 0.08 vs. 0.47 +/- 0.08; P < 0.001). In subjects with NGT, IGT and patients with diabetes, the pulsed Doppler transmitral variables were: E-wave (0.72 +/- 0.16 cm/s vs. 0.62 +/- 0.13 cm/s vs. 0.58 +/- 0.17 cm/s; P < 0.001), A-wave (0.61 +/- 0.13 cm/s vs. 0.62 +/- 0.11 cm/s vs. 0.71+/- 0.14 cm/s; P = 0.006) and E/A ratio (1.22 +/- 0.33 vs. 1.02 +/- 0.24 vs. 0.85 +/- 0.26; p < 0.001). The proportion of subjects with an E/A ratio <1 was 27.6% in the group with NGT, 55% in the group with IGT and 75.7% in the group with diabetes (P < 0.001). The E/A ratio correlated with HOMA-IR (r = -0.30, p = 0.001) and QUICKI (r = 0.37, p < 0.0001). Multiple linear regression model showed that IR (assessed by QUICKI) was an independent correlate of diastolic dysfunction (P = 0.034). CONCLUSIONS: In subjects with impaired glucose tolerance and patients with type 2 diabetes, insulin resistance is associated with impaired diastolic function of the left ventricle.     

Metabolic risk factors in southern Taiwanese with impaired fasting glucose of 100 to 109 mg/dL

This study investigates the influence of changes in impaired fasting glucose (IFG) criteria by the American Diabetes Association in 2003 in estimating the prevalence and cardiovascular risks in Taiwanese with fasting plasma glucose (FPG) between 100 and 109 mg/dL. Data came from a cross-sectional study on 1411 participants aged 30 years and older without known diabetes in southern Taiwan. Besides collection of anthropometric and biochemistry data, a 75-g oral glucose tolerance test was performed. The new IFG criteria additionally identified 14.2% of all participants as having IFG100, with FPG between 100 and 109 mg/dL, among which the percentage of normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and diabetes mellitus were 7.7%, 5.0%, and 1.5%, respectively. Mean body weight, body mass index, abdominal girth, systolic blood pressure, diastolic blood pressure (DBP), 2-hour glucose, and triglyceride were significantly higher in the IFG100 group than in normal fasting glucose (NFG) group (FPG, <100 mg/dL). Moreover, body weight, body mass index, systolic blood pressure, DBP, and 2-hour glucose were statistically higher in subgroups of IFG100/IGT than in NFG/NGT. In contrast, only DBP and 2-hour glucose were significantly higher in the IFG100/NGT group than in the NFG/NGT group. The 2003 criteria increased the prevalence of IFG and identified more IGT and diabetes. However, the increase of cardiovascular risks among newly identified IFG100 subjects came from those who concomitantly had IGT.     

Increased visceral fat and impaired glucose tolerance predict the increased risk of metabolic syndrome in Japanese middle-aged men.

BACKGROUND: Impaired glucose tolerance (IGT) represents a stage of pre-diabetes and is a risk factor for future cardiovascular disease (CVD) which is a major cause of death in type 2 diabetes. The metabolic risk factors such as elevated blood pressure (elevated BP), abdominal obesity, dyslipidemia (elevated levels of total triglycerides [TG] and low levels of HDL cholesterol), and hyperglycemia precede the onset of the metabolic syndrome that increases the risk for CVD. This clustering is commonly associated with pre-diabetic hyperinsulinemia and it reflects peripheral insulin resistance. The present study documented that a visceral fat area (VFA) >/= 100 cm (2) can replace waist-to-hip ratios (WHR) associated with IGT or IFG/IGT as a critical risk for the development of the metabolic syndrome in Japanese middle-aged men. MATERIALS AND METHODS: A total of 575 middle-aged Japanese men with fasting plasma glucose levels of 6.1 - 6.9 mmol/l (impaired fasting glucose; IFG) were enrolled in the study. After a 75-g oral glucose tolerance test (OGTT), blood samples were collected 0 - 2 h later for determination of plasma glucose, insulin concentrations and other variables. Based on the results of an OGTT, the subjects were subgrouped into categories of glucose tolerance for further study. RESULTS: Subjects with IGT or IFG/IGT had significantly higher levels of metabolic abnormalities such as high BMI, increased AUC glucose, elevated HbA1c, high VFA, elevated BP, and increased TG levels when compared to NGT (normal glucose tolerance) (p < 0.001). Compensatory hyper-secretion of insulin was seen in all pre-diabetic subjects, and was higher in IFG/IGT subjects (681 +/- 33 pmol . h/l) than NGT (480 +/- 22 pmol . h/l) (p < 0.01). The metabolic clustering including abnormal VFA, TG, HDL-C, and BP was strongly associated with the development of metabolic syndrome. Interestingly, VFA >/= 100 cm (2) adjusted for the Japanese correlates strongly with the development of the metabolic syndrome in preclinical IGT or IFG/IGT subjects, with odds ratios of 2.7 and higher. CONCLUSION: VFA >/= 100 cm (2) strongly correlates with prediabetic IGT or IFG/IGT which is possibly associated with underlying insulin resistance, and is a critical risk factor linked to the development of metabolic syndrome in Japanese middle-aged subjects with IGT or IFG/IGT.     

红细胞体积分布宽度与糖代谢异常/糖耐量异常和糖尿病相关

目的探讨红细胞体积分布宽度（RDW）与2型糖尿病（T2DM）、空腹血糖受损／葡萄糖耐量异常（IFG／IGT）的相互关系。方法对152例在我院定期进行健康体检或治疗的患者,依据血糖情况分为3组,其中T2DM组42例,IFG／IGT组38例,正常对照（NGT）组72例,采取空腹血,采用全自动血液分析仪测定RDW、血红蛋白,多功能血生化自动分析仪测定血总胆固醇、三酰甘油、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇、血肌酐、血尿素氮和空腹血糖,同时统计高血压、冠心病的发病率并分析其关系。结果RDW在T2DM组、IFG／IGT组和NGT组之间比较具有统计学差异,其中T2DM组和NGT组、IFG／IGT组比较,差异均有统计学意义（P〈0．05或P〈0．01）,IFG／IGT组与NGT组比较差异无统计学意义（P〉0．05）。多因素直线回归分析显示空腹血糖（P〈0．01）和高密度脂蛋白胆固醇（P〈0．05）是RDW的独立危险因子。结论T2DM患者RDW升高,RDW的变化与空腹血糖水平相关。