Impaired fasting glucose vs. glucose intolerance in pre-menopausal women: distinct metabolic entities and cardiovascular disease risk?

Background: Impaired glucose tolerance (IGT) is associated with an increased cardiovascular disease risk. Less is known about cardiovascular disease risk among subjects with impaired fasting glucose (IFG) or with combined IFG and IGT.

Aims: To compare body composition, body fat distribution, plasma glucose-insulin homeostasis and plasma lipid-lipoprotein profile between pre-menopausal women having either a normal glucose tolerance (NGT), isolated IFG, isolated IGT or combined IFG and IGT.

Postprandial hyperlipidemia: another correlate of the "hypertriglyceridemic waist" phenotype in men.

Fasting hypertriglyceridemia has been reported to be predictive of an exaggerated triglyceride (TG) response to an oral fat load. Abdominal obesity has also been associated with postprandial hyperlipidemia. The objective of the present study was to quantify the contribution of abdominal obesity and fasting hypertriglyceridemia to the magnitude of postprandial lipemia.

Contribution of visceral adiposity to the exaggerated postprandial lipemia of men with impaired glucose tolerance.

Objective: Impaired glucose tolerance (IGT) has been associated with alterations in numerous coronary heart disease risk factors, including postprandial hyperlipidemia. An excess visceral adipose tissue accumulation is also predictive of IGT and of an exaggerated postprandial lipemia. The objective of the present study was therefore to compare the respective contributions of visceral adipose tissue accumulation versus IGT with the variation in postprandial lipemia.

Impact of postprandial variation in triglyceridemia on low-density lipoprotein particle size.

The fasting atherogenic dyslipidemia of visceral obesity, which includes the presence of small, dense low-density lipoprotein (LDL) particles, is predictive of an increased risk of coronary heart disease (CHD). It has also been suggested that progression of atherosclerosis may be accelerated in the presence of postprandial hyperlipidemia independently from the fasting dyslipidemic state. Studies have shown that the best predictor of postprandial hyperlipidemia and of the small, dense LDL phenotype is fasting triglyceride (TG) concentration.

Is the gender difference in LDL size explained by the metabolic complications of visceral obesity?

Background: Several studies have reported a significant gender difference in low-density lipoprotein (LDL) size, with men being characterized by smaller, denser LDL particles than women, and it has been suggested that the contribution of the greater accumulation of visceral adipose tissue in men compared with women may be a factor potentially contributing to the gender difference in LDL heterogeneity.

Materials And Methods: We measured LDL particle size by 2-16% nondenaturing polyacrylamide gradient gel electrophoresis in 299 men and 231 women in whom visceral adipose tissue accumulation was measured by computed tomography. A fasting plasma lipoprotein-lipid profile was also obtained in all subjects.

Effects of prednisone withdrawal on the new metabolic triad in cyclosporine-treated kidney transplant patients.

Background: Cardiovascular disease is a major cause of morbidity and mortality after renal transplantation. Prednisone (Pred) maintenance therapy is associated with risk factors for atherosclerosis. Therefore, we were interested in quantifying the effects of Pred withdrawal on body weight and waist circumference as well as on metabolic markers of coronary heart disease risk.

Influences of the PPAR alpha-L162V polymorphism on plasma HDL(2)-cholesterol response of abdominally obese men treated with gemfibrozil.

Purpose: The effect of gemfibrozil is mediated by the activation of peroxisome proliferator-activated receptor alpha (PPAR alpha). The objective of this study was to determine whether the lipid response to gemfibrozil therapy is influenced by the PPAR alpha-L162V polymorphism.

Methods: Sixty-three abdominally obese men were randomly assigned to a 6-month-intervention program with either receiving a placebo (N = 31) or gemfibrozil (N = 32).

Evidence for impaired lipolysis in abdominally obese men: postprandial study of apolipoprotein B-48- and B-100-containing lipoproteins.

Background: Abdominal obesity has been associated with postprandial hypertriglyceridemia. The contribution of intestinally and hepatically derived lipoproteins to this exaggerated postprandial lipemic response is not known.

Objective: We examined the associations between body fatness, fat distribution, and postprandial apolipoprotein (apo) B-48 and apo B-100 concentrations measured in triacylglycerol-rich lipoproteins (TRLs).

Determinants of HDL particle size in patients with the null (P207L) or defective (D9N) mutation in the lipoprotein lipase gene: the Québec LipD Study.

The aim of the present study was to examine the impact of the defective D9N and the null P207L mutations in the lipoprotein lipase (LPL) gene on high density lipoprotein (HDL) particle size in relation to specific environmental factors such as obesity, gender and menopausal status. Analyses were carried out in 118 heterozygous carriers of the D9N mutation and 88 heterozygous for the P207L mutation. HDL particle size was measured on whole plasma by non-denaturing 4-30% polyacrylamide gradient gel electrophoresis.

Reduction of visceral adipose tissue during weight loss.

Objective: The aims of the present study were to retrospectively: (1) compare how weight loss affects the reduction of adipose tissue from three different sites between men and women; and (2) to verify whether gender differences in the reduction of adipose tissue are influenced by changes in fat mass (FM) and initial levels of fat in different compartments.

Design: Double-blind randomized treatment with fenfluramine once daily coupled to a non-macronutrient specific energy restriction.

Subjects: Seventeen obese men (age 43.

HDL particle size: a marker of the gender difference in the metabolic risk profile.

A low plasma HDL-cholesterol concentration is an important risk factor for coronary heart disease (CHD) and is often accompanied by increased triglyceride concentrations. Women have generally higher HDL-cholesterol and lower triglyceride concentrations and concomitantly are at lower risk of CHD than men. As HDL particle size is a new and potentially important marker of CHD risk, we have examined the potential gender difference in HDL particle size, assessed by nondenaturing 4-30% polyacrylamide gradient gel electrophoresis, in a sample of men (n=231) and women (n=183).

Total cholesterol/HDL cholesterol ratio vs LDL cholesterol/HDL cholesterol ratio as indices of ischemic heart disease risk in men: the Quebec Cardiovascular Study.

Background: Total cholesterol (TC)/high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C)/HDL-C ratios are used to predict ischemic heart disease risk. There is, however, no consensus on which of these 2 indices is superior. The objective of the present study was to present evidence that the LDL-C/HDL-C ratio may underestimate ischemic heart disease risk in overweight hyperinsulinemic patients with high triglyceride (TG)-low HDL-C dyslipidemia.

Effect of a low-glycaemic index--low-fat--high protein diet on the atherogenic metabolic risk profile of abdominally obese men.

It has been suggested that the current dietary recommendations (low-fat-high-carbohydrate diet) may promote the intake of sugar and highly refined starches which could have adverse effects on the metabolic risk profile. We have investigated the short-term (6-d) nutritional and metabolic effects of an ad libitum low-glycaemic index-low-fat-high-protein diet (prepared according to the Montignac method) compared with the American Heart Association (AHA) phase I diet consumed ad libitum as well as with a pair-fed session consisting of the same daily energy intake as the former but with the same macronutrient composition as the AHA phase I diet. Twelve overweight men (BMI 33.

Reduced HDL particle size as an additional feature of the atherogenic dyslipidemia of abdominal obesity.

Reduced plasma HDL cholesterol concentration has been associated with an increased risk of coronary heart disease. However, a low HDL cholesterol concentration is usually not observed as an isolated disorder because this condition is often accompanied by additional metabolic alterations. The objective of this study was to document the relevance of assessing HDL particle size as another feature of the atherogenic dyslipidemia found among subjects with visceral obesity and insulin resistance.

A new method for HDL particle sizing by polyacrylamide gradient gel electrophoresis using whole plasma.

Low plasma levels of HDL cholesterol have been associated with an increased risk of coronary heart disease. HDL particles are heterogeneous with respect to size and apolipoprotein content. The objective of the present study was to develop a method to generate lipid-stainable calibrators that would allow the assessment of HDL particle size from whole plasma, using polyacrylamide gradient gel electrophoresis (PAGGE).

[Fat distribution and metabolism].

It is well known that adipose tissue distribution is an important factor involved in the etiology of type 2 diabetes and cardiovascular diseases. Adipose tissue distribution is obviously different between men and women, men being prone to accumulate their excess of energy in the abdominal region, more specifically in the intra-abdominal depot (visceral) whereas women show a selective deposition of adipose tissue in the gluteo-femoral region. Several studies have demonstrated an association between age and adipose tissue distribution and a selective deposition of visceral adipose tissue has been reported with age, in both men and women.

Elevated C-reactive protein: another component of the atherothrombotic profile of abdominal obesity.

Recent studies have suggested that elevated plasma C-reactive protein (CRP) levels are associated with the features of insulin resistance syndrome. In the present study, we have examined the contribution of body composition measured by hydrostatic weighing and of abdominal adipose tissue (AT) accumulation assessed by computed tomography to the variation in plasma CRP levels associated with atherogenic dyslipidemia of the insulin resistance syndrome in a sample of 159 men, aged 22 to 63 years, covering a wide range of adiposity (body mass index values from 21 to 41 kg/m(2)). Plasma CRP levels showed positive and significant correlations with body fat mass (r=0.

Deterioration of the metabolic risk profile in women. Respective contributions of impaired glucose tolerance and visceral fat accumulation.

Objective: To determine whether the impaired glucose tolerance (IGT) state contributes to the deterioration of the metabolic profile in women after taking into account the contribution of visceral adipose tissue (AT) accumulation, as measured by computed tomography.

Research Design And Methods: We studied 203 women with normal glucose tolerance (NGT) and 46 women with IGT, defined as a glycemia between 7.8 and 11.

The small, dense LDL phenotype as a correlate of postprandial lipemia in men.

The atherogenic dyslipidemia of the insulin resistance syndrome is characterized by hypertriglyceridemia (hyperTG), elevated apolipoprotein (apo) B levels, reduced high-density lipoprotein (HDL) cholesterol concentrations and by an increased proportion of small, dense low-density lipoprotein (LDL) particles. Although the hyperTG-low HDL cholesterol dyslipidemia has been associated with an impaired clearance of dietary fat, the contribution of the small, dense LDL phenotype as an independent predictor of postprandial triglyceride (TG) clearance remains uncertain. We have therefore compared the postprandial TG response among three subgroups of men characterized by small, intermediate or large LDL particles in a total sample of 69 men (mean age +/- SD; 45.

[Risk factors associated with obesity: a metabolic perspective].

Obesity, especially visceral obesity, is associated with a cluster of metabolic complications increasing the risk of type 2 diabetes and coronary heart disease. It has been shown that obese patients characterized by a high accumulation of visceral adipose tissue have increased glycemic and insulinemic responses to an oral glucose load compared to normal weight individuals or to obese individuals with a low accumulation of visceral adipose tissue. Viscerally obese patients are also characterized by an unfavourable plasma lipid profile which includes elevated triglyceride and apolipoprotein B concentrations, reduced HDL-cholesterol levels as well as an increased proportion of small, dense LDL particles.

Metabolic heterogeneity underlying postprandial lipemia among men with low fasting high density lipoprotein cholesterol concentrations.

The high triglyceride (TG) and low high density lipoprotein (HDL) cholesterol dyslipidemia has been associated with increased postprandial lipemia. Although fasting TG is a powerful predictor of postprandial hyperlipidemia, the role of hypoalphalipoproteinemia in postprandial TG metabolism is uncertain. We have studied postprandial lipemia among 63 men with low fasting plasma HDL cholesterol concentrations (<0.

Contribution of visceral obesity to the deterioration of the metabolic risk profile in men with impaired glucose tolerance.

Aims/hypothesis: Impaired glucose tolerance is associated with metabolic alterations which increase cardiovascular disease risk. The contribution of hyperglycaemia to this increased risk is, however, not clear. Abdominal obesity is often observed in subjects with impaired glucose tolerance; our objective was therefore to find the contribution of visceral adipose tissue to the deterioration of the metabolic risk profile noted in subjects with impaired glucose tolerance.

Hypertriglyceridemic waist: A marker of the atherogenic metabolic triad (hyperinsulinemia; hyperapolipoprotein B; small, dense LDL) in men?

Background: The present study tested the hypothesis that simple variables, such as waist circumference and fasting plasma triglyceride (TG) concentrations, could be used as screening tools for the identification of men characterized by a metabolic triad of nontraditional risk factors (elevated insulin and apolipoprotein [apo] B and small, dense LDL particles).

Methods And Results: Results of the metabolic study (study 1) conducted on 185 healthy men indicate that a large proportion (>80%) of men with waist circumference values >/=90 cm and with elevated TG levels (>/=2.0 mmol/L) were characterized by the atherogenic metabolic triad.