Components Of Insulin Resistance Syndrome Research Articles

Пиоглитазон – забытый сахароснижающий препарат с доказанными кардиопротективными и нефропротективными свойствами

Considering that type 2 diabetes mellitus is a multicomponent disease and is associated with an extremely high risk of macrovascular complications (myocardial infarction, stroke and death from cardiovascular diseases), at present, much attention is paid to the choice of hypoglycemic drugs, given the individual characteristics of the patient. Preference is given to drugs of those classes that have a positive effect on cardiovascular outcomes. Along with relatively new molecules (inhibitors of the sodium-glucose cotransporter type 2 and agonists of glucagon-like peptide-1 receptors), the well-known drug pioglitazone, which belongs to the thiazolidinediones group, has not left the field of attention of researchers. Importantly, the cardioprotective effect of pioglitazone has been confirmed in several large randomized trials that showed a delay in atherosclerosis and a reduced risk of cardiovascular disease (PERISCOPE, CHICAGO, IRIS and PROactive). As an insulin sensitizer, pioglitazone reduces insulin resistance, has a protective effect on pancreatic β-cells, and also has a beneficial effect on components of insulin resistance syndrome (lowers blood pressure, lipid spectrum parameters) and improves the course of non-alcoholic fatty liver disease. There is evidence of possible side effects (weight gain, fluid retention, fractures), but their severity decreases with decreasing dose of the drug.

Short-Term Exercise Improves Hepatic Insulin Extraction in Individuals with Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD), the hepatic component of insulin resistance syndrome, is pathophysiologically associated with lower hepatic insulin clearance, lower fat oxidation and increased carbohydrate oxidation in a post-absorptive state. Aerobic exercise is purported to be beneficial in NAFLD. To better understand the mechanisms through which short-term, moderate intensity aerobic exercise training could exert these benefits, 13 obese, sedentary adults (age: 58±3.4 years, BMI: 34.3±1.1 kg/m2; means±SEM) with NAFLD (>5% Intra-hepatic lipid content assessed by 1H MR spectroscopy) were recruited into a 7-day exercise training program (treadmill walking for 60 mins, 5 days per week, at 80-85% maximum heart rate). Participants maintained their normal dietary patterns. Pre- and post-intervention assessments included a 75-gm OGTT, CT scans, VO2max and indirect calorimetry. Insulin sensitivity (ISI) was estimated using Soonthorpun model. Hepatic Insulin Extraction (HIE) was calculated as the molar difference in AUCs for insulin and C-peptide (HIE=1-(AUCInsulin÷AUCC-Pep)). The intervention yielded an ∼9% increase in VO2max and HIE (P<0.01). Whole-body insulin sensitivity increased by ∼43% (P<0.05). There was a significant increase in basal fat oxidation (pre vs. post: 47±6 vs. 65±6 mg/min, P<0.05) and decrease in basal carbohydrate oxidation (160±20 vs. 112±15 mg/min, P<0.05). After the intervention, HIE was positively correlated with adiponectin (r=0.56, P<0.05) and negatively correlated with TNF-α (r=-0.78, P<0.001). The change in ISI was negatively correlated with change in subcutaneous abdominal fat depot (r=-0.55, P=0.05). These data suggest that exercise may quickly reverse the pathophysiology of NAFLD by improving HIE and fasting substrate oxidation. The cardio-metabolic benefit of exercise in individuals with NAFLD is potentially mediated through changes in HIE. Disclosure A. Hari: None. C.E. Fealy: None. J.P. Kirwan: None.

The role of glucose-lowering drugs in blood pressure control in patients with type 2 diabetes mellitus

Various factors contribute the development of cardiovascular complications in type 2 diabetes mellitus (DM2): hyperglycemia and components of insulin resistance syndrome, including obesity, dyslipidemia and arterial hypertension. All of them should be considered in therapeutic strategies. In the beginning of 21st century new pharmacological agents were developed leading to the major changes in DM2 treatment. So, an ideal treatment should have not only a glucose-lowering effect, but other (“non-glycemic”) actions affecting multiple coexistent factors. Since the novel classes of antidiabetic drugs with additional favorable pleiotropic effects independent from direct glucose-lowering effect have been introduced, the choice of an appropriate agent has become more complicated and requiresindividual approach and wide knowledge in this area. The present articles reviews various groups of glucose-lowering agents and their effects on blood pressure level in DM2 patients. We believe it will help to make the right individual choice of an antidiabetic agent taking into account its pleiotropic effects.

Comparative Study of Insulin Resistance Syndrome Components in Adolescents of Parents with type 2 Diabetes Mellitus

Objectives: The objective of our study was to compare anthropometric and biochemical parameters in adolescents of one and both diabetic parents along with β cell function in both the groups. Material and methods: It is an observational analytical study which had been carried out in the Department of Biochemistry, JNMC, DMIMS (DU), Sawangi (M), Wardha. In which 50 adolescents (17±2 years of age) participated. Out of them 42 were having one diabetic parent while 8 had both diabetic parents. All subjects were evaluated for WC, BMI, BP, FPG, Lipid profile, insulin level, insulin resistance and β-cell function by standard methods. Observations and Result: Body Mass Index (BMI), serum triglyceride (TG) levels, serum insulin levels, insulin resistance and β-cell function was significantly high in adolescents of both diabetic parents as compared to one diabetic parent. These were 26.99 ± 6.67kg/m 2 , 102.04 ± 28.52 mg/dl, 22.7 ± 4.96 μIU/ml, 4.97 ± 1.37 and 211.74 ± 113.37 % respectively in adolescents of both diabetic parents as compared to 22.21 ± 3.94 kg/m 2 , 74.59 ± 27.73 mg/dl, 15.42 ± 6.85 μIU/ml, 3.50 ± 1.66 and 348.2 ± 105.8 % respectively in adolescents of one diabetic parent. Conclusion: Insulin resistance syndrome (IRS) is a constant precursor for type-2 DM, which starts 10-20 years before the development of type-2 DM. So we can say that adolescents especially whose both parents are diabetic are on the edge of development of insulin resistant syndrome and later the Diabetes mellitus.

Serum visfatin concentrations in gestational diabetes mellitus and normal pregnancy

There is conflicting data regarding visfatin in gestational diabetes mellitus (GDM). The aim of the present study was to compare serum visfatin levels between patients with GDM and subjects with normal pregnancy and to evaluate its relationship with dietary intake and components of insulin-resistance syndrome. Thirty-five patients with GDM (aged 31 ± 0.8 years, BMI = 29.6) and 35 age- and body mass index-matched healthy pregnant women (aged 29 ± 0.7 years, BMI = 28.6) between 24 and 28 weeks of gestation were studied. In addition to anthropometric and dietary intake assessments, measurements of fasting plasma levels of visfatin, glucose, insulin, hemoglobin A1c (HbA1c) and lipid profile were performed for all subjects. Plasma visfatin levels were significantly lower in pregnant women with GDM compared to healthy subjects (5.29 ± 0.47 vs. 7.76 ± 0.53, p = 0.001). After adjustment for age, maternal gestational age, body mass index, and macronutrients intake, GDM remained the independent predictor of serum visfatin concentrations (β = -1.2, p = 0.001). Serum visfatin levels were significantly correlated with log HbA1c values (r = -0.24, p = 0.03), even after adjustment for age and body mass index (β = -6.45, p = 0.05). No associations between visfatin and other parameters of the insulin-resistance syndrome as well as macronutrient intake were detectable. Plasma visfatin concentrations are lower in patients with GDM and related to glycemic control reflected by HbA1c. Furthermore, visfatin does not seem to be correlated with dietary intake in pregnant women.

Postprandial plasma adiponectin response is reduced in prepubertal premature pubarche girls

The association between premature pubarche (PP) and metabolic syndrome is controversial and not supported by some authors. The aim of this study was to determine insulin resistance syndrome, plasma adiponectin, and fatty acid profile in PP girls to discern potential confounder variables and markers of metabolic disturbances. We studied 22 prepubertal girls with a diagnosis of PP and 20 healthy controls who differed in body mass index (BMI) (19.33 ± 0.71 vs 17.30 ± 0.60). We evaluated insulin resistance syndrome components and postprandial response of adiponectin, nonesterified fatty acids, and fatty acid profile after consumption of a standardized breakfast. No lipid disturbances were detected in the PP group. High-density lipoprotein to low-density lipoprotein cholesterol ratio tended to be lower in PP girls ( P = .052), but this effect disappeared when data were adjusted for both BMI and age ( P = .480). Insulin levels tended to be higher at 2 hours in PP girls, who showed significantly higher C-peptide area under the curve. In contrast, adiponectin at 3 hours after the meal and postprandial adiponectin area under the curve were significantly lower. The PP girls showed significantly higher percentages of eicosapentaenoic acid in total plasma and plasma phospholipids. No differences were found in the postprandial fatty acid clearance rate. In conclusion, PP girls and controls differed in postprandial plasma adiponectin response and in postprandial plasma C-peptide response after both BMI and age adjustment. Cholesterol plasma disturbances were mainly attributable to their higher BMI, although n-3 polyunsaturated fatty acids were higher because of the PP.

LDL Cholesterol Is Associated With Blood Pressure in Japanese Women

HDL cholesterol is considered a component of insulin resistance syndrome or metabolic syndrome, but LDL cholesterol is not considered a component of metabolic syndrome (1–3). We have reviewed the literature and have found that there may be no report regarding the association between LDL cholesterol and blood pressure. We studied cross-sectional relationships between LDL cholesterol and other metabolic risk factors using medical checkup data from 2,449 Japanese men (age 51.9 ± 9.6 years) and 1,448 Japanese women (age 51.5 ± 9.8 years) who visited …

Cardiovascular risk factors and anthropometric measurements of adolescent body composition: a cross-sectional analysis of the Third National Health and Nutrition Examination Survey

To assess the association between certain cardiovascular risk factors that are commonly clustered among individuals with insulin resistance syndrome (IRS) and adolescents' body composition measurements. We examined a total of 1068 adolescents aged 12-16 years from the Third National Health and Nutrition Examination Survey. The sex-specific third tertiles of glucose, triglycerides, systolic blood pressure and first tertile of high-density-lipoprotein (HDL) cholesterol were used to classify the presence of each IRS component. We compared adolescents with none, one, two and three/four IRS components across a series of body composition measurements and lipid profile. About 18% of the adolescents had three or four IRS components. Overall, IRS among adolescents is more likely to be associated with body weight and measurements related to body girths and less likely to be associated with the measurements related to body lengths. Multivariate analysis results showed that the odds of being at increased risk of obesity (body mass index z-score> 0.85) were significantly greater among those with two (odds ratio (OR)=4.5; 95% CI 2.5-8.2) and three/four (OR=8.9, 95% CI 4.5-17.5) IRS components compared to those without any IRS components. Across sex, the level of non-HDL cholesterol was significantly higher among adolescents with more IRS components (P for trends <0.05). The clustered cardiovascular risk factors are strongly associated with an increased risk of obesity and higher levels of non-HDL cholesterol among adolescents.

Neuronal Intranuclear Inclusion Disease Presenting as Chronic Intestinal Pseudo‐Obstruction in the Neonatal Period in the Absence of Neurologic Symptoms

Central adiposity, a component of insulin resistance syndrome, is a risk factor for nonalcoholic fatty liver disease (NAFLD) in adults. To determine whether a similar relationship occurs in children, hepatic fat content and adipose tissue distribution were assessed in obese children at risk for NAFLD.We reviewed the charts of obese children undergoing evaluation for NAFLD because of hepatomegaly or elevated serum alanine aminotransferase (ALT) without obvious etiology. Hepatic fat fraction and adipose tissue distribution were obtained by rapid magnetic resonance imaging (MRI) techniques. Hepatic fat content was determined by a modification of the Dixon method that involves fast gradient echo. Body fat distribution was assessed by using heavily T1-weighted fast gradient echo technique on a single slice at the level of the umbilicus, and regions of interest were demarcated based upon pixel intensity threshold value including visceral adipose tissue (VAT) and subcutaneous adipose tissue content (SAT).Ten children underwent hepatic MRI only. Twenty-nine children underwent hepatic and adipose tissue distribution MRI. There was a correlation between hepatic fat fraction and VAT (r = 0.37, P < 0.05) but not body mass index or SAT. Elevated serum ALT was associated with a higher hepatic fat fraction (P < 0.001) and VAT (P = 0.06).Visceral adiposity is a risk factor for pediatric NAFLD.

Relationship of Hepatic Steatosis to Adipose Tissue Distribution in Pediatric Nonalcoholic Fatty Liver Disease

ABSTRACTObjective:Central adiposity, a component of insulin resistance syndrome, is a risk factor for nonalcoholic fatty liver disease (NAFLD) in adults. To determine whether a similar relationship occurs in children, hepatic fat content and adipose tissue distribution were assessed in obese children at risk for NAFLD.Methods:We reviewed the charts of obese children undergoing evaluation for NAFLD because of hepatomegaly or elevated serum alanine aminotransferase (ALT) without obvious etiology. Hepatic fat fraction and adipose tissue distribution were obtained by rapid magnetic resonance imaging (MRI) techniques. Hepatic fat content was determined by a modification of the Dixon method that involves fast gradient echo. Body fat distribution was assessed by using heavily T1‐weighted fast gradient echo technique on a single slice at the level of the umbilicus, and regions of interest were demarcated based upon pixel intensity threshold value including visceral adipose tissue (VAT) and subcutaneous adipose tissue content (SAT).Results:Ten children underwent hepatic MRI only. Twenty‐nine children underwent hepatic and adipose tissue distribution MRI. There was a correlation between hepatic fat fraction and VAT (r = 0.37, P &lt; 0.05) but not body mass index or SAT. Elevated serum ALT was associated with a higher hepatic fat fraction (P &lt; 0.001) and VAT (P = 0.06).Conclusion:Visceral adiposity is a risk factor for pediatric NAFLD.

Peroxisome Proliferator-Activated Receptor-??

Insulin resistance and obesity is a common health problem in the industrialized world. As a result of the availability of high-calorie food and a reduction in energy expenditure, maladaptive metabolic processes may interfere with the action of insulin and increase susceptibility for the development of atherosclerotic cardiovascular diseases. With the advent of peroxisome proliferator-activated receptors (PPARs), the mechanisms of this maladaptation and its relationship to insulin resistance syndrome components have become less obscure, promising new therapeutic approaches for this common problem. In this review we first focus on the molecular structure and cellular mechanisms of action of these receptors and then discuss how PPAR-gamma, a PPAR isoform, provides a link between adiposity, insulin resistance, and atherosclerosis.

Meta‐Analysis of the Association of the Trp64Arg Polymorphism in the β3 Adrenergic Receptor with Insulin Resistance

To clarify the possible association between the Trp64Arg polymorphism and insulin resistance (IR). Articles evaluating the effect of the Trp64Arg polymorphism on IR were identified on the MEDLINE and PubMed databases from 1995 to February, 2004. After extraction of relevant data, main and subgroup meta-analyses were performed to assess the differences in IR indices between Trp/Trp and Trp/Arg genotypes. Forty eligible papers containing 56 subgroups were included in this meta-analysis. Among a total of 12,805 subjects, 21.9% had Trp64Arg mutation: 20.8%, heterozygotes and 1.1%, homozygotes. Significant associations were found between this mutation and some indices of IR. The weighted mean difference in fasting insulin, 120-minute insulin level after oral glucose tolerance test, and homeostasis model assessment between Arg64 and Trp64 was 0.23 [95% confidence interval (CI), 0.05 to 0.42] pM, 0.89 (95% CI, 0.30 to 1.48) pM, and 0.55 (95% CI, 0.14 to 0.96), respectively. Subgroup analysis further indicated that this significant association existed only in the Asian population (p < 0.01) and in the obese (p = 0.02) and diabetes subgroups (p = 0.03). Numerous studies have been conducted to examine the relationship between the beta3-adrenergic receptor Trp64Arg polymorphism and components of IR syndrome. However, the results have been inconsistent and have led to controversy about whether this polymorphism is associated with these clinical features. The current meta-analysis demonstrated the moderate effects of the Trp64Arg polymorphism on IR in the Asian population and in obese and diabetic subgroups.

Second World Congress on the Insulin Resistance Syndrome

This is the second in a series of articles on the Second World Congress on the Insulin Resistance Syndrome, Universal City, California, 18–20 November 2004. Jacqueline Dekker (Amsterdam, the Netherlands) presented data from the Hoorn Study on the predictive power of insulin resistance syndrome diagnosis, pointing out that the public health role of identifying a person as having insulin resistance syndrome includes the ability to characterize populations to better understand the pathogenesis of adverse outcome, to allow comparison of characteristics of individuals in differing populations, and to serve a communications function in increasing risk awareness, particularly allowing identification of high-risk groups for cardiovascular disease (CVD), cancer, and diabetes. An important question is whether the existing definitions allow optimal diagnosis of high-risk groups. Comparing the Adult Treatment Panel (ATP)-III and American College of Endocrinology (ACE) definitions (1), she noted that the ACE definition starts with high-risk individuals, including non-Caucasian ethnicity, cigarette use, obesity, CVD, hypertension, polycystic ovarian syndrome (PCOS), nonalcoholic fatty liver disease, acanthosis nigricans, history of gestational diabetes or impaired glucose tolerance (IGT), and family history of type 2 diabetes, hypertension, or CVD. The Hoorn Study included 2,484 individuals aged 50–75 in 1989–1990, with follow-up examination in 1996–1998, and population registry ascertainment of morbidity and mortality. Of 2,162 without diabetes at baseline, there were 429 deaths, 145 with malignancy and 168 with CVD. Insulin resistance syndrome components for men and women included hypertension in 68 and 66%, abdominal obesity in 16 and 40%, impaired fasting glucose in 14 and 9%, IGT in 21 and 18%, high triglycerides in 35 and 29%, and low HDL cholesterol in 28 and 35%, respectively. Twenty-one and 29% of men and women, respectively, satisfied the ATP-III definition and 46 and 42% the ACE definition of insulin resistance syndrome. Despite the greater number satisfying the ACE …

Intestinal fatty acid binding protein and microsomal triglyceride transfer protein polymorphisms in French-Canadian youth

Growing evidence suggests an association between lipid abnormalities and fatty acid binding protein (FABP) and microsomal triglyceride transfer protein (MTP) gene variants. Our objectives were to determine whether Ala54Thr FABP2 and G-493T MTP polymorphisms are associated with increased risks of insulin resistance syndrome (IRS) in youth and/or modify the expression of accompanying dyslipidemia. Our study of 1,742 French-Canadians aged 9, 13, and 16 years did not provide evidence of a potential predisposition to IRS related to either FABP2 or MTP genotypes. However, we observed a heterogeneity of the FABP2 effect by IRS status on total cholesterol (TC), low density lipoprotein-cholesterol (LDL-C), and apolipoprotein B (apoB) concentrations (P for interaction=0.045, 0.018, and 0.017, respectively). Among the metabolic components of IRS, only triglyceride (TG) displayed an interaction with FABP2 polymorphism: compared with Thr/Ala and Ala/Ala, the Thr/Thr genotype was associated with a steeper increase in TC, LDL-C, and apoB parallel to TG concentrations (P <0.001). IRS did not modify the associations between the MTP polymorphism and any of the biochemical parameters. Our study suggests that the effects of FABP2 allelic variations on lipid traits are context dependent, indicating that this variant may play an important role in cardiovascular pathogenesis in the presence of IRS or hypertriglyceridemia.

Insulin resistance syndrome in a representative sample of children and adolescents from Quebec, Canada.

To estimate the prevalence of insulin resistance syndrome (IRS) in a representative sample of youth. To test for the independent contribution of insulin resistance (IR) and adiposity to clustering of metabolic risk factors. To identify the underlying components of IRS. To examine the relationship between adiposity and fasting plasma levels of free fatty acids (FFA). In 1999, we conducted a school-based survey of a representative sample of youth aged 9, 13 and 16 y in Quebec, Canada. Age-specific questionnaire data, standardized clinical measurements and a fasting blood sample were available for 2244 subjects. Fasting insulin and HOMA were used as surrogate measures of IR. In all age-sex groups, adiposity indices, blood pressure (BP), plasma glucose and triglycerides (TG) increased significantly with increasing insulin quartiles while HDL cholesterol (HDL-C) decreased. The overall prevalence of IRS defined as hyperinsulinaemia combined with two or more risk factors including overweight, high systolic BP, impaired fasting glucose, high TG and low HDL-C, was 11.5% (95% CI: 10.2-12.9). There were no significant differences in the prevalence of IRS across ages or between sexes. The independent contribution of adiposity to clustering of risk factors was stronger than that of fasting insulin (or HOMA-IR). Factor analysis revealed three factors (BMI/insulin/lipids, BMI/insulin/glucose and diastolic/systolic BP) consistent across ages suggesting that more than one pathophysiologic process underlies IRS. Although elevation of FFA might be in the causal pathway linking obesity to IR, we did not detect any consistent association between measures of fatness and fasting plasma FFA. IRS is highly prevalent in youth, even among children as young as age 9 y. Factor analysis identifies three physiologic domains within IRS with a unifying role for markers of IR and adiposity.

Relationship between C-reactive protein and visceral adipose tissue in healthy Japanese subjects.

Recent studies have suggested that the elevated C-reactive protein (CRP) levels are associated with body fat, especially visceral adipose tissue, but most of them were investigated in Westerners who had higher body mass index (BMI) than Asians. To investigate the association between CRP concentrations, parameters of visceral obesity, the insulin resistance syndrome and carotid atherosclerosis in healthy Japanese who had a lower BMI than Westerners. We explored the relationships between fatness and visceral obesity parameters [by anthropometry, bioelectrical impedance analysis and abdominal computed tomography (CT)] and CRP (high sensitivity) and examined their associations with components of insulin resistance syndrome, interleukin-6 (IL-6), tissue necrosis factor-alpha (TNF-alpha) and intima-media thickness (IMT) of common carotid arteries (CCAs) by ultrasonograms in 116 healthy Japanese subjects. In crude regression analyses, CRP was significantly associated with measures of obesity. After adjustment for age, gender and smoking, the association with CRP was stronger for parameters of visceral obesity (waist circumference, waist-to-hip ratio and visceral adipose tissue accumulation) than for other parameters of obesity. IL-6 and TNF-alpha were not associated with CRP. Blood pressure (BP), metabolic variables and CCA-IMT were also significantly associated with CRP. But, after being adjusted for age, gender, smoking and BMI, BP and high-density lipoprotein cholesterol (HDLc) were significantly associated. CRP level is associated with visceral adipose tissue and is significantly associated with the components of insulin resistance syndrome in healthy Japanese subjects. These data support a possible role of visceral adipose tissue in inflammation component of atherosclerosis, and further studies are needed to study the mechanism of CRP elevation caused by visceral adipose tissue.

Non-Alcoholic Fatty Liver Disease, Non-Alcoholic Steatohepatitis and Orthotopic Liver Transplantation

Obesity, non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are becoming increasingly common medical problems in the developed world, often in the setting of the metabolic or insulin resistance syndrome (IRS). It is predicted that by the year 2025 > 25 million Americans may have NASH-related liver disease. NASH and NAFLD also affect the donor population. The use of steatotic donor livers for liver transplantation (LT) is associated with an increased risk of primary nonfunction (PNF) in the allograft. There is particular reluctance to use steatotic livers for living donor LT. There is indirect evidence to suggest that patients undergoing LT for cirrhosis resulting from NASH may have poorer outcome, despite careful selection of LT candidates. Indeed it is likely that many potential LT candidates with NASH are excluded from LT due to co-morbid conditions related to IRS. The post-LT patient is at risk of several components of IRS, such as diabetes mellitus, hypertension, hyperlipidaemia and obesity and there is increasing recognition of de novo and recurrent NAFLD and NASH after LT. Thus NAFLD and NASH affect all aspects of LT including donors, patients in evaluation and the LT recipient.

Abdominal adiposity in U.S. adults: prevalence and trends, 1960–2000

Background. There is a large body of epidemiologic evidence linking abdominal obesity to cardiovascular diseases. Abdominal adiposity is an important component of insulin resistance syndrome. Objective. To investigate prevalence and trends in abdominal obesity in U.S. adult population. Design, setting/participants. Nationally representative cross-sectional surveys with an in-person interview and measurement of waist circumference; 23,654 adults aged 20–79 years were examined using data from U.S. National Surveys of 1960–1962 [the first National Health Examination Survey (NHES I)], 1988–1994 [the third National Health and Nutrition Examination Survey (NHANES III)] and 1999–2000 [National Health and Nutrition Examination Survey (NHANES 1999–2000)]. Abdominal obesity was defined as waist circumference ≥102 cm (>40 in.) in men and ≥88 cm (>35 in.) in women. Results. There was a gradient of increasing waist circumference over the three periods of 1960–1962, 1988–1994 and 1999–2000 in both men and women. In men, the mean waist circumferences were 89, 95 and 99 cm for 1960–1962, 1988–1994 and 1999–2000, respectively. The corresponding values in women were 77, 92 and 94 cm, respectively. A gradient of increasing prevalence of abdominal obesity from 1960 to 2000 was also observed in men and women. In men, the overall age-adjusted prevalences of abdominal obesity were 12.7%, 29% and 38.3% in 1960–1962, 1988–1994 and 1999–2000, respectively. In women, the analogous values were 19.4%, 38.8% and 59.9%, respectively. Similar trends of increasing waist circumference and abdominal obesity were observed in normal weight, underweight and obese subjects defined using body mass index (BMI). Trends of increasing abdominal obesity with increasing BMI over the three time periods were also observed. Conclusions. The increase in the prevalence of abdominal obesity in the United States between 1960–1962 and 1999–2000 has ominous public health implications across entire population, particularly among normal weight subjects. There is an urgent need to describe a public health strategy for early identification of abdominal obesity. Primary prevention of obesity, including abdominal obesity, should be a major public health priority in the United States.

Are there specific components of the insulin resistance syndrome that predict the increased atherosclerosis seen in type 2 diabetes mellitus?

Cardiovascular disease is often present in patients with newly diagnosed type 2 diabetes. It is hypothesized that both type 2 diabetes and cardiovascular disease arise from an underlying insulin resistance syndrome, including impaired glucose tolerance, hypertension, dyslipidemia, and abdominal obesity. We reviewed the literature using various epidemiologic techniques to evaluate the relation between the insulin resistance syndrome components and incident cardiovascular disease. We found that although insulin resistance is likely important in the development of cardiovascular disease seen in diabetes, lipid and blood pressure abnormalities associated with the syndrome appear to be equally important. Future studies are needed to determine the most effective treatment strategies for preventing cardiovascular disease associated with the insulin resistance syndrome and type 2 diabetes.

Relation of leptin to insulin resistance syndrome in children.

To examine the relation of leptin to insulin resistance, as measured by euglycemic insulin clamp, and insulin resistance syndrome factors in thin and heavy children. Anthropometrics, insulin, blood pressure, and leptin were measured in 342 11- to 14-year-old children (189 boys, 153 girls, 272 white, 70 black). Insulin sensitivity (M) was determined by milligrams glucose uptake per kilogram per minute and expressed as M/lean body mass (Mlbm). Children were divided by median BMI (boys = 20.5 kg/m(2); girls = 21.4 kg/m(2)) into below-median (thin) and above-median (heavy) groups. Correlation coefficients between log-leptin and components of insulin resistance syndrome were adjusted for Tanner stage, gender, and race. BMI was related to leptin in boys (r = 0.70, p < 0.001) and girls (r = 0.75, p < 0.001). Leptin was higher in girls than boys (32.6 vs. 12.3 ng/mL, p = 0.0001). Leptin levels increased in girls and decreased in boys during puberty, paralleling the changes in body fat. Leptin was significantly correlated with insulin, Mlbm, triglycerides, and blood pressure in heavy children and only with insulin in thin children. After adjustment for body fat, the correlations remained significant for insulin and Mlbm in heavy children and with insulin in thin children. Significant associations were found between leptin and insulin resistance in children, and these associations were attenuated by adjustment for adiposity. These findings at age 13 likely have long-term consequences in the development of the obesity-insulin resistance-related cardiovascular risk profile.