Cardiometabolic risk in impaired fasting glucose and impaired glucose tolerance: the Atherosclerosis Risk in Communities Study

OBJECTIVE: We compared and contrasted cardiovascular disease (CVD) risk factors, subclinical manifestations of CVD, incident coronary heart disease (CHD), and all-cause mortality by categories of impaired glucose regulation in nondiabetic individuals. RESEARCH DESIGN AND METHODS: The study included 6,888 participants aged 52-75 years who had no history of diabetes or CVD. All-cause mortality and incident CHD were ascertained over a median of 6.3 years of follow-up. RESULTS: Agreement between fasting and postchallenge glucose impairment was poor: 3,048 subjects (44%) had neither impaired fasting glucose (IFG) nor impaired glucose tolerance (IGT), 1,690 (25%) had isolated IFG, 1,000 (14%) had isolated IGT, and 1,149 (17%) had both IFG and IGT. After adjustment for age, sex, race, and center, subjects with isolated IFG were more likely to smoke, consume alcohol, and had higher mean BMI, waist circumference, LDL cholesterol, and fasting insulin and lower HDL cholesterol than those with isolated IGT, while subjects with isolated IGT had higher mean triglycerides, systolic blood pressure, and white cell counts. Measures of subclinical CVD and rates of all-cause mortality and incident CHD were similar in isolated IFG and isolated IGT. CONCLUSIONS: Neither isolated IFG nor isolated IGT was associated with a more adverse CVD risk profile.     

Differences in cardiovascular risk factors, insulin resistance, and insulin secretion in individuals with normal glucose tolerance and in subjects with impaired glucose regulation: the Telde Study

OBJECTIVE: To assess the cardiovascular risk profile, the degree of insulin resistance, and beta-cell secretion in a cohort of subjects with different categories of impaired glucose regulation (IGR): impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and combined IFG/IGT. RESEARCH DESIGN AND METHODS: We studied 902 nondiabetic subjects between 30 and 80 years of age, recruited from a cross-sectional population-based study in Telde, Gran Canaria Island, Spain. Categories of glucose tolerance were defined according to 2003 modified American Diabetes Association criteria. Risk factors for cardiovascular disease, the presence of the metabolic syndrome, and indirect measures of both insulin resistance and beta-cell function were analyzed. RESULTS: A total of 132 (14.6%) participants had isolated IFG, 59 (6.5%) isolated IGT, and 48 (5.3%) combined IFG/IGT. Groups with normal glucose tolerance (NGT) and combined IFG/IGT had, respectively, the most favorable and unfavorable levels of cardiovascular risk factors, metabolic syndrome rates, and measures of insulin resistance. Subjects with IFG and IGT showed an intermediate profile between NGT and IFG/IGT categories. We found no significant differences between IFG and IGT in cardiovascular risk factors, metabolic syndrome prevalence, or insulin resistance. The IFG group exhibited a more impaired insulin secretion than those with IGT or IFG/IGT. CONCLUSIONS: Individuals with IGR, especially those with IFG/IGT, have increased values of cardiovascular risk factors and higher indexes of insulin resistance. Groups with isolated IFG and isolated IGT present similar cardiovascular risk profiles. Subjects with IFG are characterized by more defective beta-cell function than other forms of IGR.     

Prevalence and risk factors of neuropathic pain in survivors of myocardial infarction with pre‐diabetes and diabetes. The KORA Myocardial Infarction Registry

The lowest glycemic threshold for and the risk factors associated with neuropathic pain have not been established. The aim of this study was to determine the prevalence and risk factors of neuropathic pain in survivors of myocardial infarction with diabetes, impaired glucose tolerance (IGT), impaired fasting glucose (IFG), normal glucose tolerance (NGT). Subjects aged 25–74 years with diabetes (n=214) and controls matched for age and sex (n=212) from the population‐based KORA (Cooperative Health Research in the Region of Augsburg) Myocardial Infarction Registry were assessed for neuropathic pain by the Michigan Neuropathy Screening Instrument using its pain‐relevant questions and an examination score cutpoint >2. An oral glucose tolerance test was performed in the controls. Among the controls, 61 (28.8%) had IGT (either isolated or combined with IFG), 70 (33.0%) had isolated IFG, and 81 had NGT. The prevalence of neuropathic pain was 21.0% in the diabetic subjects, 14.8% in those with IGT, 5.7% in those with IFG, and 3.7% in those with NGT (overall p<0.001). In the entire population studied (n=426), age, waist circumference, peripheral arterial disease (PAD), and diabetes were independent factors significantly associated with neuropathic pain, while in the diabetic group it was waist circumference, physical activity, and PAD (all p<0.05). In conclusion, the prevalence of neuropathic pain is relatively high among survivors of myocardial infarction with diabetes and IGT compared to those with isolated IFG and NGT. Associated cardiovascular risk factors including abdominal obesity and low physical activity may constitute targets to prevent neuropathic pain in this population.     

Changing the definition of impaired fasting glucose: impact on the classification of individuals and risk definition

OBJECTIVE: This study evaluates the impact of lowering the diagnostic threshold for impaired fasting glucose (IFG) from 6.1 to 5.6 mmol/l as proposed by the American Diabetes Association (ADA) on the prevalence of the condition, classification of individuals, and risk definition. RESEARCH DESIGN AND METHODS: A total of 1,285 employees of the Italian Telephone Company aged 35-59 years without known diabetes underwent an oral glucose tolerance test (OGTT). BMI, serum cholesterol, triglycerides, and blood pressure were measured. Medication use was recorded. RESULTS: With the new ADA criterion, the proportion of people diagnosed with IFG increased from 3.2 to 9.7%. The newly proposed IFG category identified 41% of all subjects with impaired glucose tolerance (IGT) compared with 16.2% identified with the use of the World Health Organization criterion for IFG; the improvement in accuracy has been achieved at the cost of classifying more previously "normal" subjects as having IFG (from 2.3 to 7.3%). Both IFG and IGT were associated with an unfavorable risk profile for diabetes and cardiovascular disease, with a higher estimated risk for IGT than IFG. CONCLUSIONS: Even with the revised diagnostic criterion, IFG and IGT identify distinct groups that have a different background risk. The cost/benefit of preventive measures tested in people with IGT may not apply to the new IFG category.     

蚌埠市市区葡萄糖调节受损情况调查分析

目的　了解蚌埠市区糖调节受损(IGR)患病率及其分布特征。方法　采取整群随机抽样方法，对蚌埠市区25～75岁以上人群进行横断面调查。　结果 ① 蚌埠市区居民总糖耐量减低(IGT)、总空腹血糖受损(IFG)患病率分别为6.7%(206/3073)、1.2%(36/3073)标化率为6.9％、1.1％。IGT伴IFG者患病率仅为0.2%（5/3073）。② 男性总IGT、IFG患病率分别为8.1%、1.2%，女性IGT、IFG患病率分别为5.5%、1.2%。总IGT患病率在男女之间差异有统计学意义(P<0.05)。③ 超重(OW)、肥胖(OB)人群中总IGT患病率为5.24%和14.3%，总IFG患病率为1.0%和2.7%，均明显高于体质指数(BMI)正常人群[分别为2.4%、0.3%]( P<0.05)。中心性肥胖人群中总IGT、IFG患病率分别为8.5%、1.8%，均明显高于无中心性肥胖人群[分别为4.6%、0.5%]( P<0.05)。高血压(HBP)人群中IGT、IFG患病率分别为19.1%、3.8%，均明显高于无高血压人群[分别为3.1%、0.4%]( P<0.01)。④ 干部、科技人员2型糖尿病、IGR患病率均高于工人(P＜0.05)。 ⑤ IGT、IFG冠心病、脑血管病的患病率显著高于NGT人群（均P＜0.05）。IGT、IFG视网膜病变、微量白蛋白尿患病率均高于NGT人群，其中IGT与NGT人群微量白蛋白尿患病率，差异有显著性（P＜0.05）。结论　蚌埠市区IGT患病率呈快速增长趋势，应加强对中老年人以及脑力劳动者的糖尿病健康教育；IGR患者不仅是糖尿病的高危人群，IGR阶段亦是需要给予重视的心脑血管疾病与微血管病变预防阶段。     

Elevated white blood cell count in subjects with impaired glucose tolerance

OBJECTIVE: Impaired glucose tolerance (IGT) and impaired fasting glucose (IFG) differ in their risk of all-cause and cardiovascular mortality, but previous cross-sectional studies have suggested little difference in their levels of lipids or blood pressure. We compared the white blood cell (WBC) count between subjects with IFG and IGT. RESEARCH DESIGN AND METHODS: The subjects were 4,720 nondiabetic Japanese men aged 24-84 years. Based on the 75-g oral glucose tolerance test, the subjects were classified into the following four groups: normal fasting glucose/normal glucose tolerance (n = 3,753), isolated IFG (n = 290), isolated IGT (n = 476), and IFG/IGT (n = 201). We compared the WBC count among the four groups and investigated variables that showed a significant association with the WBC count. RESULTS: The isolated IGT group had a significantly higher WBC count than the isolated IFG group (6,530 vs. 6,210/mm(3), P < 0.05). By stepwise analyses, age, triglycerides, HDL cholesterol, fasting insulin, and 2-h postchallenge plasma glucose (PG) showed an independent association with the WBC count (adjusted R(2) = 0.057). In the analysis stratified by smoking status, the WBC count was independently associated with 2-h PG and triglycerides, irrespective of smoking status. CONCLUSIONS: Individuals with isolated IGT had a significantly higher WBC count than those with isolated IFG. The WBC count was associated with 2-h PG and various components of the metabolic syndrome.     

Immunoglobulin E and mast cell proteases are potential risk factors of impaired fasting glucose and impaired glucose tolerance in humans

Aim. Mast cells are important in experimental diabetes. Plasma levels of immunoglobulin E (IgE), tryptases, and chymases are inflammatory markers of human diabetes. Whether they also correlate with the risk of pre-diabetes, however, remains unknown.

Methods and results. A total of 260 subjects 55–75 years of age were grouped as normal glucose tolerance (NGT), isolated impaired fasting glucose (I-IFG), isolated impaired glucose tolerance (I-IGT), and mixed IFG/IGT. There were significant differences in plasma levels of high-sensitivity C-reactive protein (hsCRP) (P < 0.001) and IgE (P = 0.003) among all subgroups of pre-diabetes, and chymase in I-IGT (P = 0.043) and mixed IFG/IGT (P = 0.037) subgroups compared with NGT group. High-sensitivity CRP was a risk factor in all subgroups of pre-diabetes; IgE was a risk factor of mixed IFG/IGT; and chymase was a risk factor of I-IGT and mixed IFG/IGT. Interactions between hsCRP and high waist circumference (WC), waist-to-hip ratio (WHR), or HOMA-β index, and interactions between IgE and high WC or tryptase levels all increased further the risk of developing I-IFG, I-IGT, or mixed IFG/IGT.

Conclusion. Plasma hsCRP, IgE, and chymase levels associate with pre-diabetes status. While hsCRP, IgE, and chymase are individual risk factors of pre-diabetes, interactions with metabolic parameters increased further the risk of pre-diabetes.     

Cardiovascular risk profile in individuals with borderline glycemia: the effect of the 1997 American Diabetes Association diagnostic criteria and the 1998 World Health Organization Provisional Report

OBJECTIVE: In 1997, the American Diabetes Association (ADA) recommended a new diagnostic category, impaired fasting glucose (IFG), to describe individuals with borderline glucose tolerance. On the other hand, the World Health Organization (WHO) suggested retaining the category of impaired glucose tolerance (IGT). We studied the prevalence of IFG and IGT in a multiethnic society and compared the cardiovascular risk profiles of subjects with IFG, IGT, or both IFG and IGT. RESEARCH DESIGN AND METHODS: A total of 3,568 subjects were examined from the 1992 National Health Survey of Singapore, which involved a combination of disproportionately stratified sampling and systematic sampling. Anthropometric, blood pressure, insulin, lipid profile, and uric acid measurements were taken, and a standard 75-g oral glucose tolerance test was performed after a 10-h overnight fast. RESULTS: The prevalence rates of IFG only, IGT only, and both IFT and IGT were 3.45, 10.2, and 3.4%, respectively. The degree of agreement (kappa) between the two diagnostic criteria (the ADA IFG and the WHO IGT) was only 0.25. A fasting glucose level of 5.5 mmol/l was the optimal cutoff for predicting a 2-h postload glucose level of > or =7.8 mmol/l. The following cardiovascular risk factors were higher in subjects with both IFG and IGT compared with those with either IFG or IGT alone: systolic blood pressure (131 +/- 20 vs. 125 +/- 21 and 125 +/- 19 mmHg, respectively; P < 0.05 and P < 0.001, respectively); diastolic blood pressure (77 +/- 12 vs. 73 +/- 12 and 74 +/- 12 mmHg, respectively; P < 0.05); BMI (26.2 +/- 4.2 vs. 24.4 +/- 4.0 and 24.6 +/- 4.4 kg/m2, respectively; P < 0.01 and P < 0.001, respectively); waist circumference (84.1 +/- 10.3 vs. 79.3 +/- 10.7 and 79.3 +/- 10.6 cm, respectively; P < 0.001); waist-to-hip ratio (0.84 +/- 0.08 vs. 0.82 +/- 0.09 and 0.81 +/- 0.08, respectively; P < 0.05 and P < 0.001, respectively); fasting insulin (12.1 +/- 9.7 vs. 9.2 +/- 5.3 and 9.9 +/- 7.7 mU/l; P < 0.01); insulin resistance (by homeostasis model assessment [HOMA]) (3.41 +/- 2.77 vs. 2.58 +/- 1.50 and 2.43 +/- 1.83, respectively; P < 0.01 and P < 0.001, respectively); total cholesterol (5.81 +/- 1.1 vs. 5.51 +/- 1.1 and 5.53 +/- 1.1 mmol/l, respectively; P < 0.05) and apolipoprotein(B) [apo(B)] (1.5 +/- 0.38 vs. 1.40 +/- 0.34 and 1.39 +/- 0.35 mmol/l, respectively; P < 0.01). The pattern of difference remained significant only for fasting insulin, insulin resistance (HOMA), and apo(B) (borderline) after adjustment for age, sex, and ethnic differences. CONCLUSIONS: Obvious discordance was evident in the classification of glycemic status when applying the criteria proposed by the ADA (IFG) or WHO (IGT) in a multiethnic society like Singapore. However, subjects with either IFG or IGT had similar cardiovascular risk profiles. Therefore, both criteria identified individuals at high risk for cardiovascular disease. Individuals with both IFG and IGT had a greater incidence of the cardiovascular dysmetabolic syndrome.     

Early postpartum metabolic assessment in women with prior gestational diabetes.

OBJECTIVE: To present the results of early postpartum metabolic assessment in women with gestational diabetes mellitus (GDM), to determine predictive factors for subsequent diabetes, and to investigate the association of postpartum glucose tolerance with other components of the metabolic syndrome. RESEARCH DESIGN AND METHODS: A total of 788 women were evaluated 3-6 months after a GDM pregnancy. A 75-g oral glucose tolerance test (OGTT) was performed. Cholesterol, HDL cholesterol, triglycerides, blood pressure, BMI, and body fat distribution were assessed. Clinical and obstetric history, baseline variables at the diagnosis of GDM, metabolic control during pregnancy, and index pregnancy outcome were compared in women with diabetes and women without diabetes (American Diabetes Association [ADA] criteria) after pregnancy. Multivariate logistic regression analysis was used to ascertain independent predictors of subsequent diabetes. Correlation coefficients were assessed between postpartum glucose tolerance and lipid levels, blood pressure, BMI, and body fat distribution. RESULTS: According to ADA criteria, 588 (74.6%) women were normal, 46 (5.8%) had impaired fasting glucose, 82 (10.4%) had impaired glucose tolerance, 29 (3.7%) had both impaired fasting glucose and impaired glucose tolerance, and 43 (5.4%) had diabetes. Prepregnancy obesity, recurrence of GDM, gestational age at diagnosis of GDM, glucose values in the 100-g OGTT, number of abnormal values in the 100-g OGTT, fasting C-peptide levels in pregnancy, C-peptide/glucose score in pregnancy, insulin requirement in pregnancy, 3rd trimester HbA1c levels, and macrosomia differed significantly in women with subsequent diabetes. Independent predictors of postpartum diabetes were prepregnancy obesity, C-peptide/glucose score during pregnancy, and the number of abnormal values in the 100-g diagnostic OGTT. The area under the postpartum glucose curve was positively associated with BMI, waist circumference, waist-to-hip ratio, triglycerides, and systolic and diastolic blood pressures. CONCLUSIONS: Low C-peptide/glucose score during pregnancy together with prepregnancy obesity and severity of GDM (number of abnormal values in the 100-g diagnostic OGTT) are independent predictors of subsequent diabetes. Our data suggest that regardless of obesity and severity of GDM, a beta-cell defect increases the risk of postpartum diabetes. The association of postpartum glucose tolerance with triglyceride levels, blood pressure, obesity, and regional distribution of body fat suggests that postpartum glucose intolerance anticipates a high-risk cardiovascular profile that comprises other risk factors besides diabetes.     

Abnormal glucose tolerance and increased risk for cardiovascular disease in Japanese-Americans with normal fasting glucose

OBJECTIVE: To compare the American Diabetes Association (ADA) fasting glucose and the World Health Organization (WHO) oral glucose tolerance test (OGTT) criteria for diagnosing diabetes and detecting people at increased risk for cardiovascular disease (CVD). RESEARCH DESIGN AND METHODS: Study subjects were 596 Japanese-Americans. Fasting insulin, lipids, and C-peptide levels; systolic and diastolic blood pressures (BPs); BMI (kg/m2); and total and intra-abdominal body fat distribution by computed tomography (CT) were measured. Study subjects were categorized by ADA criteria as having normal fasting glucose (NFG), impaired fasting glucose (IFG), and diabetic fasting glucose and by WHO criteria for a 75-g OGTT as having normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and diabetic glucose tolerance (DGT). RESULTS: Of 503 patients with NFG, 176 had IGT and 20 had DGT These patients had worse CVD risk factors than those with NGT . The mean values for NGT, IGT, and DGT, respectively, and analysis of covariance P values, adjusted for age and sex, are as follows; intra-abdominal fat area by CT 69.7, 95.0, and 101.1 cm2 (P < 0.0001); total CT fat area 437.7, 523.3, and 489.8 cm2 (P < 0.0001); fasting triglycerides 1.40, 1.77, and 1.74 mmol/l (P = 0.002); fasting HDL cholesterol 1.56, 1.50, and 1.49 mmol/l (P = 0.02); C-peptide 0.80, 0.90, 0.95 nmol/l (P = 0.002); systolic BP 124.9, 132.4, and 136.9 mmHg (P = 0.0035); diastolic BP 74.8, 77.7, and 78.2 mmHg (P = 0.01). CONCLUSIONS: NFG patients who had IGT or DGT had more intra-abdominal fat and total adiposity; higher insulin, C-peptide, and triglyceride levels; lower HDL cholesterol levels; and higher BPs than those with NGT. Classification by fasting glucose misses many Japanese-Americans with abnormal glucose tolerance and less favorable cardiovascular risk profiles.     

成都社区女性高血压及心血管危险因素的调查研究

目的调查成都社区女性高血压的患病率、合并心血管危险因素现状及城乡差异。方法2010年2月-10月采取整群随机抽样方法,选取成都市城市和农村共4个社区,对被选人群中所有35～70岁女性居民进行横断面调查,采用问卷、体格检查和实验室检查危险因素的方法。结果共调查成都市35～70岁社区女性居民1202例,城市社区616例,农村社区586例。患有高血压402例,总体患病率为33．44％,人口标化后患病率为35．27％。城市女性患病率42．86％高于农村女性23．55％,差异有统计学意义（X2=13．057,P〈0．001）。女性高血压患病率随年龄增加而增加。女性高血压合并心血管危险因素最多见的是腰围增粗（腹型肥胖）,其后依次是高甘油三脂（TC）33．33％、高总胆固醇33．08％、餐后2h血糖异常28．86％、空腹血糖异常（IFG）24．38％、超重或肥胖16．67％、低高密度脂蛋白胆固醇0．75％。城市女性高血压合并腰围增粗、IFG和高TC人群的比例均高于农村,差异有统计学意义（P〈0．05）。结论成都地区女性高血压患病率高,城市女性患者合并心血脑血管主要危险因素的比例高于农村。     

Impaired glucose tolerance is a risk factor for cardiovascular disease, but not impaired fasting glucose. The Funagata Diabetes Study.

OBJECTIVE: To determine whether the new category of impaired fasting glucose (IFG) recently proposed by the Expert Committee of the American Diabetes Association is a risk factor for cardiovascular disease. RESEARCH DESIGN AND METHODS: Death certificates and residence transfer documents from the cohort population consisting of participants of the diabetes prevalence study in Funagata, Yamagata prefecture, Japan, 1990-1992, were analyzed up through the end of 1996. First, the cohort population was classified into three groups: normal glucose tolerance (NGT) (n = 2,016), impaired glucose tolerance (IGT) (n = 382), and diabetic (n = 253). Then the same population was reclassified into normal fasting glucose (NFG), IFG, and diabetic. The cumulative survival rates among the groups were compared using the classical life-table method, and age-adjusted analyses, the person-year method, and Cox's proportional hazard model were adopted. RESULTS: At the end of seven observed years, the cumulative survival rates from cardiovascular disease of IGT and diabetes were 0.962 and 0.954, respectively, both significantly lower than that of NGT (0.988). The Cox's proportional hazard model analysis showed that the hazard ratio of IGT to NGT on death from cardiovascular disease was 2.219 (95% CI 1.076-4.577). However, the cumulative survival rate of IFG from cardiovascular disease was 0.977, not significantly lower than that of NFG (0.985). The Cox's hazard ratio of IFG to NFG on death from cardiovascular disease was 1.136 (0.345-3.734), which was not significant either. CONCLUSIONS: IGT was a risk factor for cardiovascular disease, but IFG was not.     

综合干预对老年人糖代谢异常进程的影响

目的分析在综合干预状态下,老年糖耐量正常者(NGT)进展为糖调节异常者(IGR),以及IGR进展为糖尿病(DM)的情况。方法于2002年对军队老年离退休干部心血管疾病危险因素进行了4年综合干预,对其中549例NGT、110例IGR定期随访4年。结果综合干预结束时,研究人群的血压、血脂、体质量指数(BMI)均有显著性下降(P<0.01)。NGT进展为IGR的比率为30.97%,其中6.74%进展为空腹血糖受损(IFG),16.39%进展为糖耐量异常(IGT),7.83%进展为空腹血糖受损合并糖耐量异常(IFG/IGT),由NGT进展为IGT的比率明显高于IFG(P<0.01);IFG检出率增加了1.11倍,进展为IFG1的比率(4.55%)明显高于IFG2(2.19%)(P<0.05)。110例IGR人群中,19.61%的IGT进展为DM,16.28%的IFG进展为DM,IGT与IFG进展为糖尿病的比例差异无统计学意义(P>0.05)。8.70%的IFG1进展为DM,25.00%的IFG2进展为DM(P>0.05);43.75%的IFG/IGT进展为DM,进展率明显高于IFG、IGT(P<0.05)。基线时IGR累计进展为DM的比率是21.82%。结论老年人进展为IGT的比率明显高于IFG,IFG/IGT进展为DM的比率明显高于单独的IFG或IGT。     

Prevalence of diabetes and impaired glucose tolerance in 64-year-old Swedish women: experiences of using repeated oral glucose tolerance tests

OBJECTIVE: The purpose of this study was to describe the prevalence of diabetes and impaired glucose tolerance (IGT) in middle-aged women and to examine the variability and practical use of the oral glucose tolerance test (OGTT) in the screening for IGT and diabetes. RESEARCH DESIGN AND METHODS: All 64-year-old women living in G?teborg, Sweden, were invited to take part in a screening examination (n = 4,856). Of these, 82% (n = 3,998) responded and 53% (n = 2,595) participated and underwent anthropometric measurements and a 75-g standardized OGTT that was repeated within 2 weeks in those not showing normal glucose tolerance (NGT). RESULTS: The prevalences of known and new diabetes, IGT at both OGTTs, and impaired fasting glucose were 4.7, 4.8, 14.4, and 6.4%, respectively. Half of the women with diabetes were previously undiagnosed, and 37% of the diagnoses were based on OGTT and diabetes 2-h values at both or one of the two examinations. Women with IGT at both OGTTs, in comparison with those with one impaired and one normal OGTT, had higher BMI, waist girth, and blood pressure. More than 40% of the women showed impaired glucose metabolism. CONCLUSIONS: Among these women, the prevalence of undetected diabetes was high and repeated OGTTs were needed to identify and not misclassify a considerable proportion of patients. The degree of glucose tolerance impairment and the number of abnormal OGTTs were directly associated with occurrence of components of the metabolic syndrome.     

Dietary variables and glucose tolerance in pregnancy

OBJECTIVE: To investigate relationships between dietary macronutrient intakes and glucose tolerance in pregnancy RESEARCH DESIGN AND METHODS: Nulliparous pregnant Chinese women diagnosed with gestational diabetes mellitus (GDM) (n = 56) were compared to age-, gestational age-, height-, and parity-matched groups with normal glucose tolerance (n = 77) and glucose intolerance (IGT) (n = 38) based on the results of an oral glucose tolerance test (National Diabetes Data Group criteria), performed between 24 and 28 weeks of pregnancy. A 24-h recall dietary assessment was also obtained at the time of screening. RESULTS: Subjects with IGT and GDM were significantly heavier (66.1 +/- 1.4 and 68.6 +/- 1.2 kg, respectively, mean +/- SEM) (P < 0.0001) than the normal group (61.2 +/- 1.8 kg) and had a higher BMI. Overall energy intake was similar between groups, as were the intakes of each macronutrient (%kcal). However, there was a highly significant reduction in polyunsaturated fat intake in the IGT and GDM groups whether expressed as %kcal, % of total fat, or fat kcal. This effect was independent of body weight or BMI whether assessed by ordinal logistic regression or by analysis of a weight- and BMI-matched subgroup of the subjects (P = 0.002 for %kcal; n = 47 normal, 26 IGT, and 43 GDM subjects). In logistic regression analysis of the complete data set, increased body weight (P < 0.0001) and decreased polyunsaturated fat intake (P = 0.0014) were both independent predictors of glucose intolerance (IGT and GDM), as were increased body weight and a low dietary polyunsaturated to saturated fat ratio. CONCLUSIONS: Increased polyunsaturated fat intake is associated with a reduced incidence of glucose intolerance during pregnancy. This finding may have major implications for dietary management of women with or at risk of developing GDM.     

Prevalences of diabetes and impaired glucose regulation in a Danish population: the Inter99 study

OBJECTIVE: To determine the age- and sex-specific prevalence of impaired fasting glycemia, impaired glucose tolerance, screen-detected diabetes, and known diabetes in a Danish population aged 30-60 years and to examine the phenotype and the cardiovascular risk profile in individuals with impaired glucose regulation. RESEARCH DESIGN AND METHODS: In the Inter99 study, 13,016 inhabitants living in Copenhagen County were invited. All participants underwent anthropometric measurements, blood samples, and a 75-g standardized oral glucose tolerance test. RESULTS: The age-specific prevalences in men were as follows: impaired fasting glycemia: 1.4-16.3%; impaired glucose tolerance: 6.9-17.8%; screen-detected diabetes: 0.7-9.7%; and known diabetes: 0-5.8%. The corresponding figures in women were 0-5.1, 10.5-17.3, 0.6-6.3, and 0.5-9%. The prevalence of impaired glucose regulation increased with age. Among individuals with diabetes, 65.6% were previously undiagnosed; this proportion was highest in the youngest age-group (82% among 45-year-old men vs. 63% among 60-year-old men, and 70% among 45-year-old women vs. 52% among 60-year-old women). Mean BMI, waist, HbA(1c), systolic blood pressure, diastolic blood pressure, and total cholesterol were significantly higher (P < 0.0001) in the individuals with impaired glucose regulation compared with individuals with normal glucose tolerance. CONCLUSIONS: This study revealed that the prevalence of type 2 diabetes is high and that still two out of three individuals are undiagnosed, indicating a need for more attention to the disease in society.     

Elevated homocysteine as a risk factor for the development of diabetes in women with a previous history of gestational diabetes mellitus: a 4-year prospective study

OBJECTIVE: To investigate the potential use of the plasma homocysteine level as a predictor of diabetes in women with a previous history of gestational diabetes mellitus (GDM). RESEARCH DESIGN AND METHODS: At 6 weeks' postpartum, baseline examination was performed in 177 GAD-negative subjects. Of these subjects, 7 who were diagnosed with diabetes at baseline were excluded from further evaluation, and 170 with normal or impaired glucose tolerance (IGT) at baseline were followed annually over 4 years. The follow-up examinations included 2-h 75-g oral glucose tolerance tests (OGTTs), lipid profiles, homocysteine levels, anthropometric measurements, history taking, diet, and lifestyle. During the OGTTs, insulin and glucose levels were assayed every 30 min. Plasma homocysteine levels were determined by ion-exchange chromatography. RESULTS: Of the 170 women, 18 (10.6%) converted to diabetes during the 4-year follow-up period. Mean age, BMI, fasting insulin, and total cholesterol at baseline (6 weeks' postpartum test) were similar in the three study groups (i.e., normal, IGT, and diabetes). Fasting glucose levels, insulin-to-glucose ratios, and homocysteine levels were significantly higher in the diabetic group (P < 0.05). Higher glucose at the time of the diagnosis of GDM and higher homocysteine levels at baseline were independently associated with the onset of postpartum diabetes. These relationships were independent of age, BMI, and family history of diabetes. CONCLUSIONS: This prospective study identified homocysteine level as a significant risk factor for development of diabetes in women with previous GDM.     

Cross-sectional and prospective associations between proinsulin and cardiovascular disease risk factors in a population experiencing rapid cultural transition.

OBJECTIVE: To examine cross-sectional and prospective associations between proinsulin and cardiovascular disease risk factors using data from a population-based study of type 2 diabetes among Native Canadians. RESEARCH DESIGN AND METHODS: Between 1993 and 1995, 72% of eligible members of a Native Canadian community participated in a baseline diabetes prevalence survey. Fasting samples were collected for glucose, C-peptide, proinsulin, lipids, and apolipoproteins. A 75-g oral glucose tolerance test was administered, and a second sample for glucose was drawn after 120 min. Blood pressure and waist circumference were determined. In the present study, subjects with normal glucose tolerance (NGT) (n = 505) and impaired glucose tolerance (IGT) (n = 74) were included in cross-sectional analyses. In 1998, 95 individuals who had IGT or NGT at baseline with an elevated 2-h glucose concentration (> or = 7.0 mmol/l) participated in a follow-up evaluation using the protocol used at baseline. Cross-sectional and prospective associations between proinsulin and cardiovascular risk factors were assessed using correlation and multiple linear regression analyses. RESULTS: After adjustment for covariates including age, sex, C-peptide, waist circumference, and glucose tolerance status, fasting proinsulin concentration was significantly associated with concurrently measured lipid and apolipoprotein concentrations (triglycerides: r = 0.18, P < 0.0001; total cholesterol: r = 0.10, P = 0.02; LDL cholesterol: r = 0.11, P = 0.01; HDL cholesterol: r = -0.16, P = 0.0002; apolipoprotein (apo) B: r = 0.17, P < 0.0001; apoAI: r = -0.11, P = 0.008). In the adjusted prospective analysis, baseline triglycerides, HDL cholesterol, and apoB were associated with changes over time in proinsulin (r = 0.23, P = 0.04; r = -0.30, P = 0.01; r = 0.23, P = 0.04; respectively). CONCLUSIONS: These results confirm previously reported cross-sectional associations between proinsulin and lipid concentrations. In addition, an unexpected association between baseline lipids and proinsulin change was documented.     

Impaired fasting glucose in cystic fibrosis

OBJECTIVE

While glucose tolerance abnormalities are common in cystic fibrosis (CF), impaired fasting glucose (IFG) has scarcely been explored. No studies have examined the relation between IFG and clinical status.

RESEARCH DESIGN AND METHODS

Data were retrieved from the University of Minnesota CF database on oral glucose tolerance tests (OGTTs) performed in 1996–2005. Subjects were identified as normal glucose tolerance (NGT), impaired glucose tolerance (IGT), or CF–related diabetes without fasting hyperglycemia (CFRD FH−). Patients with fasting hyperglycemia were excluded. The presence of IFG was assessed within each category. In a separate case-control cohort study, subjects with IFG were matched to CF control subjects by age, sex, and OGTT class to explore outcomes.

RESULTS

For the total population (n = 310), the prevalence of IFG was 22%, and by OGTT class was NGT 14%, IGT 31%, CFRD FH− 53%. Within the cohort study, mortality was significantly reduced in IFG (two vs. nine deaths, odds ratio [OR] = 0.2 [95% CI 0.04–0.9]). IFG did not confer increased risk of progression to diabetes (OR 0.66 [0.29–1.48]). Lung function was better in pediatric IFG subjects with IGT and not significantly worse in adults with IGT or adults and children with NGT and CFRD FH−. BMI was not significantly different in IFG subjects versus control subjects.

CONCLUSIONS

Contrary to expectations in patients with CF, IFG appeared to be associated with improved survival and was not associated with worse nutritional or pulmonary status or increased progression to fasting hyperglycemia.Oral glucose tolerance test (OGTT) categories were defined decades ago by the World Health Organization (WHO). In 1997, the American Diabetes Association (ADA) lowered the fasting glucose level used to define diabetes from 140 mg/dl (7.8 mmol/l) to 126 mg/dl (7.0 mmol/l) to better reflect risk of microvascular complications. The ADA also introduced the concept of impaired fasting glucose (IFG) because fasting glucose elevation in the range of 110–125 mg/dl (6.1–6.9 mmol/l) was shown to be a risk factor for the development of diabetes. In 2003, the ADA further lowered this prediabetes threshold to 100 mg/dl (5.6), again based on the future risk of developing diabetes. Using these newer criteria, the prevalence of IFG in the general population may be as high as 30% among U.S. adults (1) and 11% among adolescents (2).Oral glucose tolerance abnormalities are found in the majority of patients with cystic fibrosis (CF) (3), but IFG has been infrequently reported (4,5). No studies have reported current or future clinical outcomes in CF patients with IFG. Because impaired glucose tolerance (IGT) is associated with pulmonary function deterioration in CF (6) and risk of progression to diabetes (7), we hypothesized that IFG would also be associated with worse clinical status and the development of diabetes. Our aim was to determine the prevalence of IFG in the University of Minnesota (UM) CF population and the consequences of that diagnosis over a period of at least 3.5 years'' follow-up.     

Alcohol consumption in relation to metabolic regulation, inflammation, and adiponectin in 64-year-old Caucasian women: a population-based study with a focus on impaired glucose regulation

OBJECTIVE: The aims of this study were to examine alcohol drinking patterns in women with type 2 diabetes, impaired glucose tolerance (IGT), and normal glucose tolerance (NGT) and to investigate whether alcohol intake was associated with improved insulin sensitivity, decreased biomarkers of inflammation, and increased adiponectin levels and if these effects were limited to dysmetabolic women. RESEARCH DESIGN AND METHODS: From a cohort of 64-year-old Caucasian women, 209 with type 2 diabetes, 205 with IGT, and 186 with NGT were recruited. Alcohol consumption and medication use were assessed by questionnaires. Anthropometric data were collected, and blood glucose, insulin, HDL cholesterol, triglycerides, C-reactive protein, white blood cell count, and serum adiponectin were measured. RESULTS: Compared with the NGT group, alcohol consumption was lower in the IGT group and lowest in the diabetes group. Mean alcohol intakes of >9.2 and > or =3-9 g/day were positively associated with adiponectin and insulin sensitivity (homeostasis model assessment [HOMA]), respectively, independently of obesity, metabolic control, and other confounders. Alcohol intake correlated negatively with inflammatory markers, although this did not remain after adjustment for HOMA and waist circumference. The inverse associations between alcohol consumption and factors related to the metabolic syndrome such as HOMA, waist circumference, and inflammatory markers were more obvious among women with diabetes and IGT than in healthy women. CONCLUSIONS: In these women, moderate alcohol consumption showed beneficial associations with the prevalence of type 2 diabetes, IGT, insulin sensitivity, and serum adiponectin. There is a need to clarify whether adiponectin may be a mechanistic link and also to clarify the clinical implications of these observations.