Recently, two G-->A polymorphisms at positions -308 and -238, in the promoter of the tumor necrosis factor alpha (TNF-alpha) gene, have been identified. These variants have, in different ethnic groups, been linked to estimates of insulin resistance and obesity. The objective of the present study was to investigate whether these genetic variants of TNF-alpha were associated with features of the insulin resistance syndrome or alterations in birth weight in two Danish study populations comprising 380 unrelated young healthy subjects and 249 glucose-tolerant relatives of type 2 diabetic patients, respectively. All study participants underwent an iv glucose tolerance test with the addition of tolbutamide after 20 min. In addition, a number of biochemical and anthropometric measures were performed on each subject. The subjects were genotyped for the polymorphisms by applying PCR restriction fragment length polymorphism. Neither of the variants was related to altered insulin sensitivity index or other features of the insulin resistance syndrome (body mass index, waist to hip ratio, fat mass, fasting serum lipids or fasting serum insulin or C-peptide). Birth weight and the ponderal index were also not associated with the polymorphisms. In conclusion, although the study was carried out on sufficiently large study samples, the study does not support a major role of the -308 or -238 substitutions of the TNF-alpha gene in the pathogenesis of insulin resistance or altered birth weight among Danish Caucasian subjects.
The purpose of the study was to investigate the associations of abdominal obesity and overall obesity with the risk of acute coronary events.
Body mass index indicating overall obesity and waist-to-hip ratio and waist circumference indicating abdominal obesity were measured for 1346 Finnish men aged 42-60 years who had neither cardiovascular disease nor cancer at baseline. There were 123 acute coronary events during an average follow-up of 10.6 years. In Cox regression analyses adjusted for confounding factors, waist-to-hip ratio (P=0.009), waist circumference (P=0.010) and body mass index (P=0.013) as continuous variables were associated directly with the risk of coronary events. These associations were in part explained by blood pressure, diabetes, fasting serum insulin, serum lipids, plasma fibrinogen, and serum uric acid. Waist-to-hip ratio of > or =0.91 was associated with a nearly threefold risk of coronary events. Waist-to-hip ratio provided additional information beyond body mass index in predicting coronary heart disease, whereas body mass index did not add to the predictive value of waist-to-hip ratio. Abdominal obesity combined with smoking and poor cardiorespiratory fitness increased the risk of coronary events 5.5 and 5.1 times, respectively.
Abdominal obesity is an independent risk factor for coronary heart disease in middle-aged men and even more important than overall obesity. Since the effect of abdominal obesity was strongest in smoking and unfit men, the strategy for lifestyle modification to prevent coronary heart disease should address these issues jointly.
Comment In: Eur Heart J. 2002 May;23(9):687-911977990
To assess the association between the common missense variant, Y64R, in the gene encoding the beta 3-adrenergic receptor, ADRB3, and intermediate phenotypes related to obesity and NIDDM in Canadian Oji-Cree.
We determined genotypes of the ADRB3 Y64R polymorphism in 508 clinically and biochemically well-characterized adult Oji-Cree, of whom 115 had NIDDM. We tested for associations with multivariate analysis of variance.
We found the ADRB3 R64 allele frequency to be 0.40 in this population, which is the highest yet observed in a human population. Furthermore, 15% of subjects were R64/R64 homozygotes, compared with a virtual absence of homozygotes in European study samples. However, we found no statistically significant associations of the ADRB3 Y64R genotype either with the presence of NIDDM, with indexes of obesity, or with intermediate quantitative biochemical traits related to NIDDM.
Despite the very high frequency of the ADRB3 R64 allele in this sample of aboriginal people, it was not associated with any metabolic phenotype. This suggests that the ADRB3 R64 allele is probably not a major determinant of obesity or NIDDM in these aboriginal Canadians.
Several studies have shown that insulin action deteriorates with age, possibly mediated through accumulation of abdominal fat. We determined peripheral insulin action in elderly and younger men who had participated in a large population study (the Tromsø Study). To 15 elderly participants aged 71 to 77 years, we individually matched 15 younger participants aged 31 to 33 years (Y1) by body mass index (BMI). A second young group (Y2) comprised 15 participants also aged 31 to 33 years, but with BMI representative of this age group in the population study. All underwent hyperinsulinemic euglycemic clamps (0.4 mU/kg/min), oral glucose tolerance tests, and determinations of Vo2max. Insulin sensitivity index (ISI=glucose disposal per kg fat-free mass [FFM] divided by steady-state insulin concentration) did not differ between the elderly and Y1, but was higher in Y2 (0.10+/-0.01, 0.12+/-0.01, and 0.17+/-0.02, P=.0011 by analysis of variance [ANOVA]). Adjustment by waist circumferences (analysis of covariance [ANCOVA]) abolished this difference. In univariate analysis of pooled data, ISI correlated negatively to body fat indices, serum triglycerides, and free fatty acids (FFA), and positively to Vo2max. In multiple regression analysis, waist circumference and triglycerides were the only independent predictors of insulin sensitivity, whereas age had no impact. The results confirm that the decline in insulin action seen in elderly people is related to increased abdominal fat rather than aging per se.
BACKGROUND: Alimentary lipemia has been associated with coronary heart disease and common carotid artery intima-media thickness (IMT). This study was designed to investigate the relations of subclasses of postprandial triglyceride-rich lipoproteins (TRLs) with IMT. METHODS AND RESULTS: Ninety-six healthy 50-year-old men with an apolipoprotein (apo) E3/E3 genotype underwent an oral fat tolerance test and B-mode carotid ultrasound examination. The apo B-48 and apo B-100 contents of each fraction of TRLs were determined as a measure of chylomicron remnant and VLDL particle concentrations. In the fasting state, LDL cholesterol (P
With the purpose of study of a degree of an expressiveness and character of mutual relation of fabric components of a soma (osteal, muscular and fatty) at the people of youthful and first mature age in norm and at a scoliosis I-II of a degree is surveyed on a method R.N. Dorohov (1994) 2756 men--inhabitants of the South of Russia. The received results specify that for the people with a scoliosis I-II of a degree are characteristic micro-(person of a female) and macrosomn (person of a male) types at the low contents of muscular and fatty masses of a body in a combination with grasilisation of a skeleton and prolate extremities. Taking into account a rather high degree of a hereditary determination of the dimensional characteristics of an organism it is possible to consider (count) fixed somatotipic of feature as morphological markers of predisposition to scoliotic deformation.
We studied fat distribution and metabolic risk factors in 434 38-year old women selected from population registrars in 5 cities in different parts of Europe. In the present study we focussed on the geographical variation in serum concentrations of free testosterone and its relation to measures of obesity, fat distribution and indicators of cardiovascular risk (serum lipids, insulin, and blood pressure). There were significant differences in free testosterone levels (F = 5.4, p less than 0.001) with lowest levels in Polish women (mean +/- SEM: 1.56 +/- 0.08 pg/ml) and highest in women from Italy (2.07 +/- 0.12 pg/ml). In the pooled data, free testosterone levels were correlated with several anthropometric variables (strongest with subscapular/triceps ratio r = 0.27, with subscapular skinfold and waist/thigh circumference ratio r = 0.25 p-values less than 0.001). In addition, free testosterone was positively correlated with serum total cholesterol (r = 0.11), HDL/total cholesterol fraction (r = 0.12), serum insulin (r = 0.20) and diastolic blood pressure (r = 0.15). These associations remained significant after adjustment for body mass index and waist/thigh ratio (not for diastolic blood pressure) but were no longer significant after further adjustment for insulin levels. There were considerable differences in strength of the associations mentioned between the 5 centers. We conclude that degree of obesity, fat distribution and serum levels of free testosterone all, to a limited degree, contribute to the metabolic profile of randomly selected 38-year old women but that adjustment for such variables increases the differences in metabolic profiles between women from different centers of Europe.
Quality of exercises performed by 16-year-old gymnast-girls of high qualification using 106 various anthropometric profiles has been stated experimentally. The data obtained have been subjected to statistic, correlative and factor analysis. As demonstrares analysis of 190 correlation coefficients between the anthropometric parameters (AP) of the gymnast-girls, 72 coefficients have meanings of a strong interconnections, 104--of middle and 14--of poor interconnections. The direction of the interconnections is positive. Factorization of matrix of the gymnast-girls AP makes it possible to distinguish three factors; their summational contribution into the total variance sample makes 79.1%. Exercises of a certain technical structure, at other similar conditions, are performed by the gymnast-girls possessing a peculiar anthropometric profile. Besides, the gymnast-girls, demonstrating at various levels similar technical results, are like in their anthropometric profile. For example, when performing the same qualified exercise, in the first group are included the gymnast-girls with the mark 9.93 from 10. AP of these gymnast-girls are: body mass 43 kg, body length 155 cm, length of their arms up to the styloid radial point 50 cm, length of the legs up to the lower tibial point 75 cm. With increase of the four AP mentioned, tendency to decreasing mark in the quality of the exercise performance is noted. Comparison of the gymnast-girls AP with the AP earlier established makes it possible, to some extent, to prognosticate sporting improvement.