Extent and composition of coronary lesions in relation to fat distribution in women younger than 50 years of age

To ascertain the relationship between the extent and composition of coronary arterial lesions and the regional distribution of fat in healthy women younger than 50 years of age, a series of 30 forensic autopsy cases were investigated. Body height and weight, waist and hip circumferences, and the thickness of the subscapular and abdominal subcutaneous fat were measured; the body mass index (BMI) and waist-to-hip ratio (WHR) were calculated, and omental and mesenteric fat deposits were weighed. The extent of coronary lesions was measured by planimetry, and the thickness of the intima-media was measured by computerized image analysis. Intimal macrophage foam cells and smooth muscle cells were detected by immunohistochemistry, and macrophages were quantified. The intima media thickness in the left anterior descending artery, circumflex artery, and right coronary artery varied significantly across the tertiles of WHR when age and BMI were adjusted, being highest when WHR exceeded 0.87. The thickest lesions also contained the largest numbers of macrophage foam cells. The intima-media thicknesses were highest with increased amounts of intraperitoneal fat. These results indicate that the severity of clinically silent coronary lesions in younger female individuals is associated with increased WHR and increased amounts of intraperitoneal fat. These results emphasize the importance of WHR as a coronary risk indicator in younger women.     

Visceral fat and coronary pathology in male adolescents.

OBJECTIVE: To find out whether coronary atherosclerotic lesions and their precursors in male adolescents are associated with the amount of mesenteric and omental fat. SUBJECTS: A series of 40 forensic autopsy cases of ante-mortem healthy boys of 13-19 y of age were investigated. METHODS: Body height and weight, waist and hip circumferences and the thickness of the abdominal subcutaneous fat were measured, the body mass index (BMI) and waist-to-hip ratio (WHR) were calculated, and omental and mesenteric fat deposits were weighed. The intimal surface of the coronary arteries covered by lesions was measured by planimetry, and the thickness of the intima was measured by computerized image analysis. Intimal macrophage foam cells and smooth muscle cells were detected by immunohistochemisty, and macrophages were quantified. RESULTS: The intima thickness of the left anterior descending artery (LAD) and in the thickest lesion varied significantly across the tertiles of visceral fat when adjusted for age, being highest when the sum weight of omental and mesenteric fat exceeded 358 g. The intima thickness of the circumflex artery (CX) varied significantly across the tertiles of waist circumference when adjusted for age. No statistically significant associations with other indicators of obesity were found. Macrophage foam cells were present in the lesions and their maximal density/mm(2) correlated significantly with intima thickness in the LAD and CX. The maximal density of macrophages in CX and the right coronary artery (RCA) and in the thickest lesion varied significantly across the tertiles of visceral fat when adjusted for age, being highest when the amount of fat exceeded 358 g. The macrophage density also varied significantly across the tertiles of waist circumference in all vessels. CONCLUSIONS: The results indicate that early macrophage-rich coronary lesions are associated with increased amounts of visceral fat in adolescent male individuals. This emphasizes the importance of effective prevention of weight gain in individuals with a tendency to accumulate visceral fat at an early age.     

Myocardial infarction and coronary pathology in severely obese people examined at autopsy

OBJECTIVE: To find out the severity of coronary atherosclerosis and its relationship to body structure and adiposity in severely obese people with body mass index (BMI) > or = 35.0 kg/m(2) and to examine the incidence and characteristic features of myocardial infarction and other fatal coronary events in this population. DESIGN: Autopsy reports were analyzed, including data on age, height, weight, abdominal subcutaneous fat thickness, heart weight, coronary atherosclerosis, histopathology and toxicology. Myocardial collagen and arteriolar structure were examined by computerized image analysis. SUBJECTS: Forensic autopsy cases (n=166) with a BMI > or = 35.0 kg/m(2) examined in 1992-1998 were collected from the files of the Department of Forensic Medicine, University of Oulu, Finland. RESULTS: In a large number of the severely obese individuals, the coronary arteries were either lesion-free or only fatty streaks were observed (38% of men, 44% of women) and coronary thrombosis was rare (3.8% of men and 1.6% of women). Cardiac causes of death predominated, cardiomyopathy being the commonest. Myocardial infarction was the immediate cause of death in 14.4% of men and 12.9% of the women, and it was associated with increased heart size in men. Coronary atherosclerosis without any infarction had been determined as the cause of death in 8.6% of the men and 8.1% of the women. Abdominal subcutaneous fat thickness had a significant negative association with the severity of coronary atherosclerosis in the women, and a decrease in the arteriolar media/lumen ratio with increasing BMI was observed in the men. CONCLUSIONS: A considerable number of severely obese people have only fatty streaks and no marked stenosis in their coronary arteries, even at an advanced age. The large amounts of subcutaneous adipose tissue in obese women may provide some protection against coronary lesion development, which could be an estrogen effect. Myocardial infarction in severely obese men is associated with cardiac hypertrophy. The significance of the BMI-related dilatation of the myocardial arterioles in men and its relationship to a remodelling of the epicardial arteries will require future investigations.     

Expression of estrogen receptors in the coronary arteries of young and premenopausal women in relation to central obesity

OBJECTIVE: To examine the relationship of coronary estrogen receptor (ER) expression with atherosclerotic lesions and central fat accumulation in premenopausal women. SUBJECTS: A total of 52 female forensic autopsy cases aged between 18 and 49 y. METHODS: Height, body weight and waist and hip circumferences were measured and body mass index (BMI) and waist-to-hip ratio (WHR) were calculated. Intima thickness or maximal thickness of the plaque were measured from samples taken from the left anterior descending artery (LAD). Macrophage infiltration and smooth muscle cells were localized by immunostaining. ER was detected immunohistochemically and by Western blot analysis, and the ER immunopositive area in the intima was measured. RESULTS: ER immunoreactivity was observed in the intima in 60% of the samples, and it was most intense in the advanced plaques near the lipid core next to the maximal intensity of macrophage staining. The ER immunopositive area had a significant positive correlation with LAD intima thickness, which in turn was significantly correlated with waist circumference and WHR when adjusted for age and BMI. CONCLUSIONS: Premenopausal women with the central type of fat accumulation have advanced coronary plaques in which ER expression is localized near the lipid-rich and macrophage-rich zone. The higher expression of ER in the arterial plaques may represent a compensatory mechanism against atherosclerosis.     

Association between low thigh fat and non-alcoholic fatty liver disease

Background and Aim:  Some people have a fatty liver despite having low visceral fat and a low body mass index (BMI). We investigated whether fat distribution, especially thigh subcutaneous fat and thigh intramuscular fat, is associated with non-alcoholic fatty liver disease (NAFLD).
Methods:  The patients consisted of 408 men and women. NAFLD was defined by an ultrasound scan and excluded other liver diseases. Visceral, subcutaneous abdominal, intramuscular, and subcutaneous thigh adipose tissue was measured by computed tomography.
Results:  The frequency of NAFLD decreased over a quartile of thigh fat independently of BMI in the female patients. Additional adjustments for age and visceral fat area did not change the results. This finding was not observed in the male patients. To investigate the relationship between each fat distribution and NAFLD, we performed a logistic regression analysis. Fat distribution was divided into four groups: visceral fat, abdominal subcutaneous fat, thigh subcutaneous fat, and thigh intramuscular fat. All four fat components were chosen as variables for the regression model. Age, BMI, and the homeostasis model assessment (HOMA) index were then adjusted successively. A larger subcutaneous fat area was negatively associated with NAFLD after adjustment for visceral fat and abdominal subcutaneous fat areas in women, but not in men. It did not change even after age adjustment, BMI, and the HOMA index.
Conclusion:  Low femoral subcutaneous fat amounts were shown to be independently associated with fatty liver disease in women. These results show the importance of accurate measurements of other regional body compositions as well as visceral fat amounts when investigating NAFLD.     

Relation of birth weight to lean and fat thigh tissue in young men

BACKGROUND: Birth weight is positively associated with body mass index (BMI, kg/m2) in later life, but is inversely associated with cardiovascular risk. To understand this paradox, we examined the relationships between birth weight, adult BMI, and estimations of lean and fat tissue in young men. METHODS: From 192 applicants for military service (ages 17-22 y, mean BMI 23.2 kg/m2) with known birth weights we measured the circumference and anterior skinfold thickness at midthigh to estimate thigh muscle+bone area and subcutaneous fat area. Linear regression models including birth weight as the independent variable were adjusted for race and adult height. RESULTS: BMI was linearly associated with birth weight (standardized regression coefficient, [SRC]=+0.27; P=0.0004), as was the thigh muscle+bone area (SRC=+0.22; P=0.0029), but not the thigh subcutaneous fat area (SRC=+0.13; P=0.086). The BMI-birth weight association was reduced by 68% when the regression model was further adjusted for thigh muscle+bone area. Separate adjustment for thigh subcutaneous fat, however, reduced the BMI-birth weight association by only 30%. Waist circumference was also associated with birth weight (SRC=+0.24; P=0.0014), sagittal abdominal diameter was weakly associated (SRC=+0.17; P=0.028), but waist/thigh ratio and abdominal diameter index were not associated with birth weight. INTERPRETATION: The larger BMI associated with higher birth weight may reflect increments in lean tissue more than increments in fat. Birth weight's influence on lean tissue is observed in the thigh and, among fit young men, perhaps at the waist. Increased muscularity in young men may partly explain the cardiovascular benefit in middle age ascribed to higher birth weight.     

Effect of weight loss and regional fat distribution on plasma leptin concentration in obese women.

OBJECTIVES: To investigate how circulating leptin concentrations are related to regional fat distribution and whether moderate weight loss alters these relationships. DESIGN: A 6 month, clinical weight reduction trial with measurements before and after weight loss. SUBJECTS: 38 healthy, obese women (age: 44.3+/-9.9 y, BMI: 34.0+/-4.0 kg/m2). MEASUREMENTS: The following measurements were made. 1. indices of obesity and fat distribution: weight, body mass index (BMI), hip circumference (peripheral fat), waist circumference, total body fat (bioelectrical impedance), abdominal fat distribution: visceral fat and abdominal subcutaneous fat (ultrasonography); and 2. Biochemical measurements: plasma leptin and serum insulin. RESULTS: Baseline plasma leptin concentrations were three-fold higher in obese women than in normal weight controls. After weight loss averaging 8.4 kg (9.0%), plasma leptin decreased by a mean of 22.3% (P < 0.001), corresponding to body fat decrease of 16.6% (P < 0.001), abdominal subcutaneous fat decrease of 17.4% (P < 0.001) and visceral fat decrease of 18.7% (P < 0.001). The total amount of body fat correlated with plasma (serum) leptin before (r = 0.64, P < 0.001) and after (r = 0.75, P < 0.001) weight loss. Plasma leptin concentrations expressed per kg of body fat did not change significantly during weight loss. After controlling for body fat, baseline leptin concentrations were significantly associated with hip circumference (r = 0.57, P < 0.001) but not with any indices of abdominal fat distribution. After weight loss the associations became significant for hip and waist circumference as well as for visceral and abdominal subcutaneous fat. Changes in leptin correlated with changes in all indices of obesity except visceral fat. CONCLUSIONS: Plasma leptin concentrations reflect not only total fat mass but also adipose tissue distribution, especially peripheral fat. Plasma leptin values per kilogram of fat mass do not change significantly with modest weight loss.     

Polymorphisms in the leptin receptor gene, body composition and fat distribution in overweight and obese women

OBJECTIVE: Leptin is an adipocyte-secreted hormone involved in body weight regulation, acting through the leptin receptor, localised centrally in the hypothalamus as well as peripherally, amongst others on adipose tissue. The aim of this study was to evaluate whether polymorphisms in the leptin receptor (LEPR) gene were related to obesity and body fat distribution phenotypes, such as waist and hip circumferences and the amount of visceral and subcutaneous fat. METHODS: Three known LEPR polymorphisms, Lys109Arg, Gln223Arg and Lys656Asn, were typed on genomic DNA of 280 overweight and obese women (body mass index (BMI)>25), aged 18-60 y. General linear model (GLM) analyses were performed in 198 pre- and 82 postmenopausal women, adjusting the data for age and menopausal state, plus fat mass for the fat distribution phenotypes. RESULTS: No associations were found between the LEPR polymorphisms and BMI or fat mass. In postmenopausal women, carriers of the Asn656 allele had increased hip circumference (P=0.03), total abdominal fat (P=0.03) and subcutaneous fat (P=0.04) measured by CT scan. Total abdominal fat was also higher in Gln223Gln homozygotes (P=0.04). Also in postmenopausal women, leptin levels were higher in Lys109Lys homozygotes (P=0.02). CONCLUSION: In conclusion, polymorphisms in the leptin receptor gene are associated with levels of abdominal fat in postmenopausal overweight women. Since body fat distribution variables were adjusted for fat mass, these results suggest that DNA sequence variations in the leptin receptor gene play a role in fat topography and may be involved in the predisposition to abdominal obesity.     

Birth weight and body composition in young adult men--a prospective twin study.

OBJECTIVES: To evaluate the association between birth weight and adult body composition in twins, controlling for maternal and genetic influences. DESIGN: Twins were randomly selected from the East Flanders Prospective Twin Survey, a population-based historic twin cohort. SUBJECTS: Male members of 229 twin pairs between 18 and 34 y of age who participated in the Prenatal Programming Twin Study. MEASUREMENTS: Adult body mass, height, BMI, lean body mass, sum of skinfolds and waist-to-hip-ratio. Lean body mass, sum of skinfolds and waist-to-hip-ratio were also adjusted for body mass. Intra-pair difference in adult anthropometric measures between the heaviest and the lightest twin at birth. RESULTS: Per kg increase in birth weight, body mass (4.2 kg), height (3.3 cm), lean body mass (3.1 kg) and to a lesser extent BMI (0.49 kg/m(2)) increased, whereas waist-to-hip-ratio (-1.4%) and sum of skinfolds (-0.11 s.d.) decreased, when adjusted for body mass. In a pair-wise analysis, the heavier twin at birth was taller and heavier as an adult, but, when adjusted for body mass, he had a lower waist-to-hip-ratio, less subcutaneous fat, and more lean body mass, compared to his lighter sib. Intra-pair difference in body composition was associated with intra-pair birth weight difference in monozygotic and dizygotic twins. CONCLUSIONS: An adverse intra-uterine environment, as measured by birth weight, is associated with more subcutaneous and abdominal fat and less lean body mass in adulthood. This association is independent of maternal and genetic influences. However, we cannot exclude the existence of genes that act on both birth weight and adult body composition.     

Body composition and metabolic factors in obese children and adolescents

OBJECTIVE: Body composition is associated with metablic factors in adults; however, data are limited regarding obese children. This study was undertaken to assess body composition, regional fat distribution, and metabolic factors in obese 6-18-y-old children and adolescents. DESIGN: Cross-sectional assessment. SUBJECTS: Thirty-six obese children and adolescents, (mean+/-s.e.m.) age 11.8+/-0.5 y, BMI 34.1+/-1.2 kg/m(2). MEASUREMENTS: Body composition was assessed by dual energy X-ray absorptiometry and computerized tomography. Fasting insulin, glucose and leptin levels, and the homeostasis model assessment of insulin sensitivity (HOMA-IR) were assessed. RESULTS: The girls had significantly lower glucose levels than the boys. The ethnic group differences (African American children vs white children) in fat mass, total CT fat, subcutaneous CT fat, insulin level, leptin level, and higher HOMA-IR were not significant after adjusting for age or pubertal stage. These differences in abdominal fat and subcutaneous abdominal fat were also not independent of total body fat or BMI. No ethnic group differences in visceral abdominal fat were noted. Insulin level and HOMA IR were associated with leptin level (independent of fat mass) and fat mass. Leptin level was associated with fat mass, total CT fat, and subcutaneous CT fat; however the associations between the CT fat measures and leptin were not independent of total body fat mass. CONCLUSIONS: Neither visceral abdominal fat, subcutaneous abdominal fat, insulin levels, or insulin resistance differed by ethnic group when adjusted for age or pubertal status. This contrasts with findings in adults and non-obese children which suggest lower levels of visceral fat and higher insulin levels and insulin resistance in African American children and adolescents.     

Waist circumference and body composition in relation to all-cause mortality in middle-aged men and women

OBJECTIVE: Waist circumference is directly related to all-cause mortality when adjusted for body mass index (BMI). Body fat and fat-free body mass, when mutually adjusted, show with increasing values an increasing and decreasing relation to all-cause mortality. We investigated the association of waist circumference and body composition (body fat and fat-free mass), mutually adjusted, to all-cause mortality. DESIGN: A Danish prospective cohort study with a median follow-up period of 5.8 y. SUBJECTS: In all, 27 178 men and 29 875 women, born in Denmark, aged 50-64 y, and without diagnosis of cancer at the time of invitation. MEASUREMENTS: Waist circumference and body composition estimated from impedance measurements. Cox's regression models were used to estimate the mortality rate ratios (RR). RESULTS: Waist circumference was strongly associated with all-cause mortality after adjustment for body composition; the mortality RR was 1.36 (95% confidence intervals (CI): 1.22-1.52) times higher per 10% larger waist circumference among men and 1.30 (95% CI: 1.17-1.44) times higher among women. Adjustment for waist circumference eliminated the association between high values of the body fat mass index (BFMI) and all-cause mortality. The association between fat-free mass index (FFMI) and mortality remained unaltered. CONCLUSION: Waist circumference accounted for the mortality risk associated with excess body fat and not fat-free mass. Waist circumference remained strongly and directly associated with all-cause mortality when adjusted for total body fat in middle-aged men and women, suggesting that the increased mortality risk related to excess body fat is mainly due to abdominal adiposity.     

Viscerally obese women with normal body weight have greater brachial-ankle pulse wave velocity than nonviscerally obese women with excessive body weight

OBJECTIVE: To confirm the association of visceral obesity and brachial-ankle pulse wave velocity (baPWV) and to compare metabolic indices and baPWV between individuals who have normal body weight but are viscerally obese and individuals with excessive body weight who are not viscerally obese. PATIENTS AND MEASUREMENTS: We recruited a total of 150 women, aged 22 to 67 years. We assessed body composition, measured by computed tomography (CT), and divided the study population into four groups, based on visceral adipose tissue area (normal, normal body weight but viscerally obese, excessive body weight but not viscerally obese, and excessive body weight and viscerally obese). The baPWV was measured, using a volume plethysmographic instrument. RESULTS: Despite lower levels of total body fat, the women who had a normal body weight but were viscerally obese had a higher plasma triglyceride level and baPWV measurement and greater subcutaneous fat area (SFA) and thigh SFA than the women with excessive body weight who were not viscerally obese. After adjustment for age, mean blood pressure (BP), body mass index (BMI), triglyceride levels, fasting insulin levels, and free fatty acid (FFA) levels, baPWV was independently correlated with abdominal visceral fat area, as measured by CT (P = 0.001). CONCLUSIONS: Mean baPWV was higher in women with normal body weight who were viscerally obese than in women who had excessive body weight but were not viscerally obese, and abdominal visceral fat was an independent factor for baPWV. These results suggest that early detection and intervention in viscerally obese individuals, even those within a normal BMI range, could be needed to prevent atherosclerosis and cardiovascular disease (CVD).     

Fat distribution and insulin resistance in young adult nonobese asian Indian women

Abstract Although Asian Indian (people of Indian subcontinent descent) men are shown to have higher total and truncal body fat as well as greater insulin resistance compared to white men matched for total body fat and age, data in women are not conclusive. The objective of this study was to compare total and regional fat distribution and insulin sensitivity between healthy young premenopausal Asian Indian and white women of similar body mass index (BMI). Twenty Asian Indian women (65% immigrants and 35% first generation living in Dallas) and 31 white women of similar age and BMI [age 24±3 vs. 25±4; BMI 22±4 vs. 23±5; mean±standard deviation (SD) in Asian Indian and white, respectively] without diabetes were evaluated with anthropometric measurements, underwater weighing for percentage of total body fat mass, magnetic resonance imaging of whole abdomen for measurement of abdominal subcutaneous and intraperitoneal fat mass, and euglycemic-hyperinsulinemic clamp study for measurement of insulin sensitivity. There were no differences in waist or hip circumference, total body subcutaneous abdominal or intraperitoneal fat mass, fasting plasma glucose, and insulin levels between Asian Indian women and white women. The peripheral glucose disposal rate (Rd) during hyperinsulinemic-euglycemic clamp was found to be almost identical in the two study groups (median value of 6.9 and 6.8?mg/min per kg of body weight, for Asian Indians and whites, respectively). For similar total or regional fat content, the glucose disposal rate was comparable in the two study groups. In conclusion, we demonstrate that young Asian Indian women do not have excess abdominal or intraperitoneal fat or insulin resistance for similar BMI compared to white women of European descent.     

The prediction of abdominal visceral fat level from body composition and anthropometry: ROC analysis.

OBJECTIVE: To evaluate the merit of body mass index (BMI), % body fat, waist circumference and waist-to-hip ratio as predictors of abdominal visceral fat (AVF) level. DESIGN: Cross-sectional measurements obtained from 458 female and 331 male subjects of French Canadian descent with an age range from 18-72 y. MEASUREMENTS: AVF level was assessed by computed tomography. BMI was calculated as weight (in kg) divided by stature2 (in m), body density was derived from underwater weighing and % body fat was computed from the estimate of body density with the Siri equation. Waist-to-hip ratio was calculated as waist circumference divided by hip circumference. Receiver operating characteristic (ROC) curves were used to identify the optimal cut-off points. RESULTS: In younger women (< 40 y, n = 258), waist-to-hip ratio was the poorest predictor of AVF level with areas under the ROC curves (Az) ranging from 0.684-0.716, sensitivity (Sen) from 63.3-68.8% and specificity (Spe) from 64.0-67.5%, whereas the Az, Sen and Spe for other predictors ranged from 0.924-0.983, 87.0-96.8, and 83.4-92.7, respectively. The same trend was observed in older (> or = 40 y, n = 200) women, although differences between waist-to-hip ratio and other predictors were less pronounced. In older men, waist circumference was the best overall predictor (Az from 0.88-0.92), whereas BMI showed the lowest Az values (0.831-0.875, P < or = 0.001 vs waist circumference). In younger men, BMI had the smallest Az (P < 0.007 vs others) with the lowest AVF cut-off point (100 cm2). However, with higher AVF cut-offs the differences were not significant. CONCLUSION: Waist circumference is the best overall predictor of abdominal visceral obesity, whereas in women waist-to-hip ratio is a poor indicator of AVF and its use as a surrogate measure of visceral fat should be avoided.     

Association of Periaortic Fat and Abdominal Visceral Fat with Coronary Artery Atherosclerosis in Chinese Middle Aged and Elderly Patients Undergoing Computed Tomography Coronary Angiography

Background and Aims:Coronary artery disease (CAD) is usually caused by atherosclerosis, which is associated with general obesity and stronger associations with localized ectopic fat depots have been reported. We measured body ectopic fat distribution in Chinese patients to determine the association with coronary artery atherosclerosis (CA).Methods:Patients undergoing coronary computed tomography angiography (CCTA) who agreed to participate in the study (n = 750, 50.4% men, mean age 64.8 years) had cardiovascular disease and risk assessment. Body ectopic fat depots were measured from CT and their association with CA, determined from CCTA, was evaluated by univariate and multivariate logistic regression models.Results:CAD with CA (CAD-CA) was present in 57.2% of participants with CAD of moderate/severe CA (CAD-msCA) present in 23.5% and both were significantly more frequent in men than in women. Overall, men had greater body mass index (BMI) but there was no difference in waist circumference (WC) between genders. However, significantly higher visceral adipose tissue (VAT) and periaortic fat volume (PAFV) were observed in men, whereas women had significantly higher abdominal subcutaneous adipose tissue (SAT). With increasing age, there was a significant decline in BMI, WC and SAT in men, but a significant increase of WC and VAT, PAFV and epicardial fat volume (EFV) in women. A high proportion of non-calcified plaques was observed in CAD-CA, 55.3% in CAD of minimal/mild CA (CAD-mmCA) with 38.7% exclusively non-calcified plaques, and 59.7% in CAD-msCA with multiple type plaques containing non-calcified ones. Multivariate logistic regression showed a significant association of PAFV with CAD-CA and CAD-msCA that was independent of general obesity and clinical risk factors, and independent of abdominal obesity in the highest PAFV quartile patients. VATA was associated with an increased prevalence of CAD-msCA in the patients in the upper 2 VATA quartiles that was independent of clinical risk factors and both general and abdominal obesity.Conclusions:We found age and gender differences of body ectopic fat distribution in Chinese patients with higher VAT and PAFV in men and higher SAT in women. With increased age, there was a decline of WC and SAT in men but not in women and an increase in WC, VAT and PAFV in women but not in men. PAFV was significantly associated with overall CAD-CA and CAD-msCA, while VAT was associated with CAD-msCA.     

Relationships between changes in abdominal fat distribution and insulin sensitivity during a very low calorie diet in abdominally obese men and women

BACKGROUND AND AIM: Little is known about the association between abdominal obesity and insulin sensitivity during rapid weight loss. We assessed the role of visceral and subcutaneous fat as determinants of insulin sensitivity during rapid weight loss in obese persons with the metabolic syndrome. METHODS AND RESULTS: Twenty abdominally obese individuals [11 women and 9 men, body mass index (BMI) 35.8+/-3.5 kg/m2] with the metabolic syndrome underwent a very-low-calorie diet (VLCD) for nine weeks. At baseline, the computed tomography (CT) measured area of total (r=-0.50, p=0.033) and visceral fat tissue (r=-0.48, p=0.043), but not that of subcutaneous fat tissue (r=-0.34, p=0.17), correlated with insulin sensitivity as assessed by the quantitative insulin sensitivity check index after adjusting for sex and age. The 18 subjects who completed the study lost 14.8 kg during the VLCD. Total, visceral and subcutaneous abdominal fat tissue decreased by 22%, 29% and 17%, respectively. The decrease in total (r=-0.51, p=0.035) and subcutaneous abdominal fat (r=-0.57, p=0.017), but not visceral fat (r=0.11, p=0.68), correlated with the increase in insulin sensitivity. Waist circumference did not offer any additional information concerning abdominal fat distribution or insulin sensitivity compared with that provided by BMI at baseline or after weight loss. The waist/hip ratio was not associated with the CT measures of abdominal fat distribution or insulin sensitivity. CONCLUSIONS: Total abdominal fat may be more important than its compartmentalisation in abdominally obese individuals with the metabolic syndrome. In this subgroup of individuals with obesity, the measurement of waist circumference and the waist/hip ratio offered little additional information over that provided by BMI at baseline or after weight loss.     

Relation of epicardial and pericoronary fat to coronary atherosclerosis and coronary artery calcium in patients undergoing coronary angiography

Fat surrounding coronary arteries might aggravate coronary artery disease (CAD). We investigated the relation between epicardial adipose tissue (EAT) and pericoronary fat and coronary atherosclerosis and coronary artery calcium (CAC) in patients with suspected CAD and whether this relation is modified by total body weight. This was a cross-sectional study of 128 patients with angina pectoris (61 +/- 6 years of age) undergoing coronary angiography. EAT volume and pericoronary fat thickness were measured with cardiac computed tomography. Severity of coronary atherosclerosis was assessed by the number of stenotic (> or =50%) coronary vessels; extent of CAC was determined by the Agatston score. Patients were stratified for median total body weight (body mass index [BMI] 27 kg/m(2)). Overall, EAT and pericoronary fat were not associated with severity of coronary atherosclerosis and extent of CAC. In patients with low BMI, those with multivessel disease had increased EAT volume (100 vs 67 cm(3), p = 0.04) and pericoronary fat thickness (9.8 vs 8.4 mm, p = 0.06) compared with those without CAD. Also, patients with severe CAC had increased EAT volume (108.0 vs 69 cm(3), p = 0.02) and pericoronary fat thickness (10.0 vs 8.2 mm, p value = 0.01) compared with those with minimal/absent CAC. In conclusion, EAT and pericoronary fat were not associated with severity of coronary atherosclerosis and CAC in patients with suspected CAD. However, in those with low BMI, increased EAT and pericoronary fat were related to more severe coronary atherosclerosis and CAC. Fat surrounding coronary arteries may be involved in the process of coronary atherosclerosis, although this is different for patients with low and high BMIs.     

Obesity, body fat and coronary atherosclerosis

BACKGROUND: Recent prospective studies have provided compelling evidence that obesity is a risk factor for the occurrence of clinical coronary events. However, the link between angiographically determined coronary atherosclerosis and obesity still remains controversial. We conducted this cross-sectional study in a clinical setting to investigate the relation of the obesity and body fat (BF) with angiographically defined coronary atherosclerosis. PATIENTS AND METHODS: Six hundred and seventy-three men (median age 64 years) and four hundred and twenty-eight women (median age 69 years) who underwent coronary angiography for suspected or known coronary heart disease were analyzed. The body mass index (BMI) and the BF were used as main exposure variables, and either the presence of significant (> or =50%) coronary diameter stenosis or a coronary artery disease severity score were defined as outcome variables, in a sex-specific logistic regression analysis. RESULTS: Among male patients, BF was slightly higher with increasing number of vessels involved (adjusted P for trend <0.05). In contrast, BMI showed no association with presence and severity of coronary artery disease (CAD). The odds ratios (ORs) for the presence of significant stenosis across quartiles of BMI were 1.0 (reference), 0.9, 1.1 and 0.7 (adjusted P for trend 0.61). This result did not differ between younger and older men. Among females, however, both BF and BMI were not significantly associated with an increasing number of vessels involved. CONCLUSION: These results suggested that BF may be predictive of an increasing number of coronary vessels involved among male patients, but not among female patients. This study failed to detect a positive association of presence and severity of CAD with BMI.     

Obesity and abdominal fatness associated with undernutrition early in life in a survey in Rio de Janeiro

BACKGROUND: Undernutrition early in life has been associated with chronic diseases and obesity among adults. Our study tested the hypothesis by examining the association between low stature, a marker of early poor nutrition, with obesity and abdominal fatness among adults. METHODS: A population-based survey was conducted in 1996, among 2040 households, with a non-response rate of 11.2%. Weight, height, waist and hip circumference, and skinfolds were measured at home. RESULTS: Age-adjusted prevalence of body mass index (BMI) greater than 25 kg/m2 was 32% more frequent among adult men, and 60% more frequent among adult women, comparing the first to the fourth quintile of height. A J-shaped curve describes the association between weight and the sum of skinfolds with stature after adjusting for confounding by age, energy intake, physical activity, smoking, age at menarche, and race. The adjusted odds ratio of obesity (BMI>30 kg/m2) for short stature, compared to normal stature, was 1.57 with a 95% confidence interval (CI) = 0.90-2.71 among men and 1.84 with a 95% CI=1.10-3.06 among women. Short stature was associated with the risk of abdominal fatness only among women, with an odds ratio=1.77; 95% CI=1.10-2.83. CONCLUSIONS: Increased risk of obesity and abdominal fatness among women of short stature, a marker for undernutrition early in life, was not explained by racial and socio-economic conditions, energy intake or age at menarche.