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C Bouchard

Publications and source records attributed to C Bouchard.

645 records · Page 36Linked to original sources
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Adipose tissue distribution and plasma lipoprotein levels in obese women. Importance of intra-abdominal fat.

Prospective studies have shown that excess abdominal fat is associated with an increased risk of coronary heart disease and related death. We used computed axial tomography (CAT) to assess the association between deep and subcutaneous abdominal adipose tissue and plasma lipoprotein levels in a sample of 52 premenopausal obese women aged 35.7 +/- 5.5 years (mean +/- SD). Whereas the plasma lipoprotein concentration were not significantly correlated with fat mass, the data obtained by CAT indicated that the absolute amount of deep abdominal fat was negatively correlated with high density lipoprotein cholesterol (HDL-CHOL) levels (r = -0.35, p less than 0.01), as well as with HDL-CHOL/low density lipoprotein (LDL)-CHOL, HDL-apoprotein-(apo) A-I/LDL-apo B, and HDL2-CHOL/HDL3-CHOL ratios (-0.32 less than or equal to r less than or equal to -0.40, 0.05 greater than p less than 0.01). Adipose tissue deposition at the mid-thigh region determined by CAT did not show any significant relationship with plasma lipoprotein levels. When subgroups of women with comparable ages and adiposity but with high and low intra-abdominal fat accumulation were compared, women with a high accumulation of intra-abdominal fat displayed significantly lower HDL-CHOL (p less than 0.001), HDL2-CHOL (p less than 0.001), HDL3-CHOL (p less than 0.01), and HDL-apo A-I (p less than 0.05) levels, as well as reduced HDL-CHOL/LDL-CHOL (p less than 0.01), HDL-apo A-I/LDL-apo B (p less than 0.05), and HDL2-CHOL/HDL3-CHOL ratios (p less than 0.05) in comparison with obese women with low accumulations of intra-abdominal fat.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdomen↗
PubMedDate not supplied

Genetic and environmental determinants of serum lipids and lipoproteins in French Canadian families.

The contribution of genetic and environmental factors in serum triglycerides (TG), total cholesterol (CHOL), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), and HDL-C/CHOL ratio were studied in 1630 subjects from 375 families of French descent by using a path analysis procedure. Familial correlations were computed in several pairs of biological relatives and relatives by adoption after adjustment for age and gender effects and after further adjustment for physical fitness, level of habitual physical activity, total body fat and fat distribution, diet, smoking, and alcohol consumption. The model of path analysis allowed the separation of transmissible variance (t2) into genetic (h2) and cultural (b2) components of inheritance. Under the most parsimonious solution and after adjustment for age, gender, and concomitants, the transmissible variance was entirely accounted for by genetic factors (t2 = h2), with h2 estimates of 0.52, 0.55, 0.60, and 0.63 for TG, CHOL, LDL-C, HDL-C, and HDL-C/CHOL, respectively. These estimates were similar to those obtained after adjustment for age and gender effects only. The contribution of nontransmissible environmental factors ranged from 0.48 for TG to 0.37 for HDL-C/CHOL ratio. These results suggest that both genetic and environmental factors contribute to the variation in blood lipids and lipoproteins in this population and that nongenetic influences are not associated with cultural factors transmitted across generations.

Adolescent↗
PubMedDate not supplied

Role of hepatic-triglyceride lipase activity in the association between intra-abdominal fat and plasma HDL cholesterol in obese women.

Intra-abdominal fat content is an important variable in the association between regional body fat distribution and plasma high density lipoprotein (HDL) cholesterol levels. In the present study, we report on the role of plasma postheparin lipases as well as abdominal and femoral adipose tissue lipoprotein lipase activities in the association between body fat distribution and plasma lipoprotein levels. Postheparin plasma lipoprotein lipase (LPL), hepatic-triglyceride lipase (H-TGL), abdominal and femoral adipose tissue (AT)-LPL activities and plasma lipoprotein levels were measured after an overnight fast in a sample of 16 obese women (ages 36.0 +/- 6.1 years [mean +/- SD], percent body fat 46% +/- 6%). Computed axial tomography was used to assess body fat distribution. Plasma postheparin LPL activity was neither correlated with total adiposity nor with the level of intra-abdominal fat. Intra-abdominal fat deposition was, however, positively correlated with H-TGL activity (r = 0.66, p less than 0.005). Furthermore, covariance analysis showed that the association between intra-abdominal fat and H-TGL was independent from total adiposity. Plasma postheparin LPL and abdominal AT-LPL activities showed no significant correlation with plasma lipoprotein levels, whereas femoral AT-LPL activity was positively correlated with the HDL2 cholesterol/HDL3 cholesterol ratio (r = 0.51, p less than 0.05). H-TGL activity was, however, negatively correlated with HDL2 cholesterol (r = -0.60, p less than 0.05), but not with HDL3 cholesterol (r = -0.28, NS). These results suggest that the high H-TGL activity in obese women with excess deep abdominal fat could be responsible for the reduction in plasma HDL2 cholesterol levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdomen↗
PubMedDate not supplied

The effects of exercise-training on energy balance and adipose tissue morphology and metabolism.

The effects of exercise training on energy expenditure, energy intake, fat cell size and adipose tissue lipolysis have been reviewed. Individuals engaged in regular and intense training programmes, e.g. long distance runners, seem to exhibit an elevated resting metabolic rate but moderate training is not accompanied by any important change. Diet-induced thermogenesis is a significant component of daily energy expenditure. It is still unclear whether or not exercise or training causes significant alteration in the thermic response to food intake. Energy expenditure associated with physical activity can play a meaningful role in body composition and adipose tissue metabolism. Largest weight losses have been achieved with programmes of long duration, presumably without marked compensation in food intake. However, it has been shown repeatedly that an increase in energy expenditure with exercise training tends to be associated with an elevation in food intake in free-living individuals. Weight loss is concomitant with a reduction in fat cell diameter and, when caused by an exercise training programme, it is generally accompanied by an increase in fat cell lipolytic activities. There are clear indications that weight loss induced by exercise training has a much higher fat content than weight loss caused by dieting. In addition, data suggest that exercise training may result in a greater depletion of fat stores than a low calorie diet, thus delaying the advent of the resistance phase to fat loss. Data on human subjects derived from well controlled energy balance and metabolic experiments are needed to further advance our understanding about the effects of exercise training on the adipose tissue.

Adipose Tissue↗
PubMedDate not supplied

[Preliminary studies of the structured diagnostic interview for personality disorders: SCID II].

The aim of the study was to compare control subjects and consultant patients with the SCID II (interview and questionnaire), then to compare clinical diagnosis with the SCID II (interview and questionnaire). The preliminary study was carried out to assess the feasibility of the procedure. This appraisal was conducted with a group of patients (n = 26) and a control group (n = 16). Only the patients were diagnosed according to DSM IV criteria. The patients and the control group completed the Mini-Mult and the SCID II (questionnaire and interview). The two groups were matched on sex, age and educational level. The two groups were discriminated on all Mini-Mult scales but one: the internalization index. The results showed that the SCID questionnaire and the SCID interview differentiate the two groups. The SCID questionnaire showed high sensitivity in the group of patients. It is a more efficient instrument to screen control subjects except one personality disorder (obsessive-compulsive). The diagnostic agreement between the clinical diagnosis and the structured interview was poor. However our results are comparable to the other studies.

Adult↗
PubMedDate not supplied

Familial resemblance for coronary heart disease risk: the HERITAGE Family Study.

The objective of this study was to quantify familial resemblance for coronary heart disease risk in 260 Black and 427 White participants in the HERITAGE Family Study. Coronary heart disease risk was estimated using a coronary heart disease risk index (CHDRI) computed from the revised Framingham Heart Study algorithm, based on age, LDL-cholesterol, HDL-cholesterol, blood pressure, diabetes, and smoking status. Using a familial correlation model to test hypotheses regarding familial aggregation, significant familial resemblance was detected in both Blacks and Whites. There were significant sibling correlations in both Blacks and Whites, while spouse correlations were significant only in the White sample. The maximal heritabilities, which have to be interpreted cautiously in light of negligible parent-offspring correlations, were 34% and 53% in Whites and Blacks, respectively. Thus, the maximal heritability, which includes both genetic and non-genetic sources of variation, is higher in Blacks than Whites, and explains a significant proportion of the total phenotypic variance. The results indicate that risk of coronary heart disease runs along family lines, and common environmental effects are important in explaining the observed familial resemblance.

Adult↗
PubMedDate not supplied

Lack of correspondence among measures identifying the obese.

Correspondence among eight measures commonly used to identify the obese was investigated in 225 men and 212 women 18-59 years of age. Measures included weight, body mass index (BMI), relative weight, skinfold thicknesses at triceps and subscapular sites, the sum of four skinfolds, percentage body fat (%BF) determined hydrostatically, and total weight of fat. Intercorrelations within various measures of body mass and total fat are high (0.86-0.99), while correlations between the two skinfolds, and among measures of body mass, subcutaneous fatness, and total body fat are much lower (0.57-0.70). The amount of variation in %BF accounted for by correlations with the other individual measures of obesity (other than fat weight) ranges from 32% to 48%. When analyzed categorically, the upper quintiles of the various measures poorly identify the same individuals as the fattest. The median chance-adjusted correspondences were 0.57 and 0.64 for men and women, respectively, with single values as low as 0.40. Analyses of variance (ANOVA) indicate the misclassification occurring among upper quintiles is nonrandom with respect to mean levels of these obesity measures. We find a considerable lack of correspondence among measures commonly used to identify the obese. This lack of correspondence may lead to unanticipated dissimilarity among people variously classified as obese and to bias regarding risks of associated disease or mortality.

Adipose Tissue↗
PubMedDate not supplied

[Genetics and obesity in man].

This brief review constitutes a synthesis of some of the research conducted in our laboratory about the role of inheritance in human variation observed for subcutaneous fat, total fat mass and subcutaneous fat distribution. Our first studies were of the genetic epidemiology type and were conducted on a cohort of 1,698 subjects from 409 families of French descent living in the greater Québec city area. These studies have shown that heritability of the amount of subcutaneous fat was almost zero, while the additive genetic effect reached about 25% of human variation, after statistical control over the effects of age and gender, for total fat mass and regional subcutaneous fat distribution. On the other hand, there are considerable individual differences in the response to overfeeding and those that pertain to body weight and body composition, and the various components of daily energy expenditure in subjects kept inactive, are mainly determined by the genotype. These findings come from a study on the response to chronic overfeeding, sustained for 22 consecutive days, undertaken with 6 pairs of identical twins. In general, our research shows that there are individuals who are more at risk of becoming obese because of undetermined genetic characteristics but that are apparently associated somehow with the various components of habitual energy expenditure.

France↗
PubMedDate not supplied

[Stress].

Explore the source record for details and available documents.

Adult↗
PubMedDate not supplied

[Social support network evolution after the birth of their first baby: comparison between lower and middle class mothers].

The social support networks of a group of low socio-economic status (S.E.S.) mothers (n = 87) and a group of higher S.E.S. mothers (n = 44) are described and compared at the 30th week of pregnancy and at the third week after the birth of their first baby. The evolution of the support networks for these two groups of mothers during this period is also examined. A modified form of the ASSIS from Barrera has been used to measure the social support network. Results show that, during pregnancy, the social support network of low-S.E.S. mothers is more restricted than that of higher S.E.S. mothers. Although the actual number of people around them after the birth of the baby did not increase, low-S.E.S. mothers said they felt a slight increase in the number of people available to give support in some way. They also reported that conflicts were more frequent with some of them. For higher S.E.S. mothers, all social network variables remained stable from pregnancy through the first postpartum month.

Adult↗