Regional fat distribution and cardiometabolic risk in healthy postmenopausal women

BackgroundRegional fat distribution is an important determinant of cardiometabolic risk after menopause. The aim of the present study was to investigate the association between indices of fat distribution obtained by Dual-energy X-ray Absorptiometry (DXA) and representative cardiometabolic risk factors in a cohort of healthy postmenopausal women.MethodsIn this cross-sectional study, cardiometabolic risk factors were correlated with a variety of central and peripheral fat depots obtained by DXA, in a total of 150 postmenopausal women, free of diabetes and cardiovascular disease (age 54 ± 7 years, BMI 29.6 ± 5.8 kg/m², mean ± 1 SD).ResultsAfter adjusting for age and total adiposity, DXA-derived indices of central and peripheral fat distribution displayed opposite associations (positive versus negative) with the examined cardiometabolic risk factors. In multivariate regression analysis, thoracic fat mass % was an independent predictor of blood pressure, HOMA index and triglycerides, abdominal fat mass % was an independent predictor of high sensitivity C-reactive protein, and abdominal-to-gluteofemoral fat ratio was an independent predictor of high density lipoprotein cholesterol. An index of peripheral fat distribution, gluteofemoral fat mass %, proved to be the most important determinant of metabolic syndrome (Odds Ratio 0.76, 95% confidence intervals 0.67–0.87, p < 0.001), independent of total and central adiposity.ConclusionDXA-derived indices of regional fat distribution such as thoracic, abdominal and gluteofemoral fat, correlate significantly with cardiometabolic risk factors in healthy postmenopausal women, and may serve as clinically useful tools for evaluating cardiometabolic risk after menopause.     

Evidence for bone mass and body fat distribution relationship in postmenopausal obese women

The measurement of bone mass, a reliable predictor of osteoporotic fractures, in obese subjects has yielded conflicting results and bone mass has been reported to be elevated, normal or decreased. These observations indicate that factors other than body weight may be involved in the less risk for osteoporosis in obese subjects. In order to clarify the role of body fat distribution on bone density we studied sixty postmenopausal overweight/obese women with Body Mass Index (BMI) over 25 kg/m(2). Thirty five age-matched, nonobese postmenopausal women, served as controls. Bone mineral density (BMD) was measured at the proximal and ultradistal non dominant forearm using a double energy X-ray absorption (DEXA) apparatus. The waist/hip circumferences ratio (WHR) was used, in obese group, as an anthropometric estimation of the abdominal (WHR>0.85) to lower-extremity (WHR>0.85) fat proportion. The results were analyzed by Student t-test, ANOVA, and multiple linear regression analysis. No difference was found in BMD between obese group and controls, but a highly significant (P<0.001) positive correlation has been documented between proximal and ultradistal radius bone mineral density and waist/hip ratio in the obese group. Instead not significant correlation was found with BMI. Regional fat topography may influence the bone mass independently of total adiposity and visceral fat was the primary parameter accounting for higher bone mineral density values. These finding suggest that women with android-like obesity are protected from osteoporosis.     

Is serum cortisol associated with body fat distribution in postmenopausal women?

The associations of body fat distribution, as measured by waist-to-hip circumference ratio (WHR), with fasting serum cortisol and adrenocorticotropic hormone (ACTH) were examined in 72 healthy postmenopausal women. WHR was not significantly correlated (P greater than 0.05) with either cortisol (r = -0.11) or ACTH (r = 0.10). There were no differences in either mean serum cortisol or ACTH for women in the highest tertile of WHR compared to those in the lowest tertile of WHR, even after adjustment for overall body mass. These results suggest that neither cortisol or ACTH is associated with body fat distribution in postmenopausal women.     

Impact of fat distribution on metabolic,cardiovascular and symptomatic aspects in postmenopausal women

The aim of this study was to investigate the anthropometric, metabolic, cardiovascular and symptomatic profile in gynoid and android postmenopausal women. Forty five postmenopausal women aged 50 to 60 years were divided into two groups according to fat distribution [waist-to-hip ratio (WHR)]: gynoid group (WHR between 0.68 and 0.8; N?=?13) and android group (WHR?>?0.8; N?=?32). Body composition, skinfold thickness, serum/plasma estradiol, creatinine, urea, lipid profile, glucose and insulin, maximal exercise testing and menopause rating scale (MRS) were evaluated. The android group when compared to the gynoid group showed (P?<?0.05): (i) higher values of body mass, BMI, waist circumference, body fat, lean mass and skinfold thickness; (ii) higher values of estradiol, triglycerides, very low-density lipoprotein (VLDL) and insulin levels with lower insulin sensitivity (%S) and greater insulin resistance (%IR) index; (iii) higher blood pressure (BP) during rest and lower maximal heart rate (HRmax) during maximal exercise testing and; (iv) higher scores of the somatic and urogenital-sexual symptoms. This study suggests that android postmenopausal women develop features that can lead to metabolic syndrome (MetS) and future cardiovascular disease (CVD), and these women may present higher scores of somatic and urogenital-sexual symptoms.     

Effects of raloxifene on body fat distribution and lipid profile in healthy post-menopausal women

The aim of our prospective, randomised, controlled and open-label clinical study was to evaluate in healthy post-menopausal women the effects of raloxifene (RLX) on body fat distribution and lipids, and the correlations between these parameters. The fat distribution, by dual energy X-ray absorptiometry, and lipids were evaluated at baseline and after 1 yr in 50 post-menopausal women: 25 were treated with RLX 60 mg/die, while 25 served as control group (CG). After 1 yr, we observed in RLX-users a slight reduction of fat mass in trunk and central region and an increase in legs and, in relation to CG, significantly lower values of adiposity in trunk and abdominal region (p < 0.05). At the same time, HDL-cholesterol (HDL-C) and apolipoprotein A1 (ApoA1) were significantly increased in relation to baseline values and CG (p < 0.05) and apolipoprotein B (ApoB), total cholesterol/HDL-C, LDL cholesterol/ HDL-C, and ApoB/ApoA1 ratios significantly decreased compared to baseline values and CG (p < 0.05). No correlation was underlined among lipids and regional fat distribution. These results highlight the positive effect of RLX on lipids and suggest, for the first time, that RLX promotes the shift from android to gynoid fat distribution, and prevents the uptrend of abdominal adiposity and body weight compared with untreated women.     

绝经后妇女心外膜脂肪体积与代谢综合征的相关性研究

目的研究绝经后妇女心外膜脂肪体积（EFV）与代谢综合征（MS）的关系。方法通过多层螺旋CT测量EFV。结果MS组EFV平均为187．20cm^3,正常对照组（NC）EFV平均为137．33cm^3,两组EFV差异有统计学意义（P〈0．01）。Logistic回归分析,收缩压（SBP）、EFV进入回归方程。具有3项MS成分的患者EFV平均为159．00cm^3,具有3项MS成分的患者EFV平均为208．36cm^3,两组EFV差异有统计学意义（P〈0．01）。结论EFV与MS密切相关,EFV随着MS成分的增加而增加。EFV可能是MS的一个非侵袭性预测评估指标之一。     

Relationship of body fat distribution to the metabolic clearance of insulin in premenopausal women

The effects of body fat distribution on the metabolic clearance rate of insulin (MCR) and its relationship to peripheral insulin sensitivity (M/I) and androgenic activity were assessed in six nonobese and 20 obese premenopausal women with varying waist-to-hip girth ratio (WHR). As an index of androgenic activity, plasma levels of the sex hormone binding globulin (SHBG) and percentage free testosterone (%FT) were determined. The mean MCR in the obese and nonobese groups were similar (571 +/- 29 vs 578 +/- 31 ml/min/m2). Within the obese group, MCR varied between 401 and 822 ml/min/m2 and was inversely correlated with the WHR (r = -0.50, P less than 0.05). The reduction in MCR with upper body fat localization was observed at both sub- and supra-maximal plasma insulin levels. MCR correlated negatively with fasting and postglucose challenge plasma insulin levels and positively with M/I. MCR also correlated with plasma SHBG and %FT levels. We conclude that upper body fat localization is associated with diminished insulin clearance. This diminution is closely aligned with the degree of peripheral insulinemia and insulin sensitivity. The increase in androgenic activity may contribute to the aberrant insulin clearance observed in upper body obese subjects.     

Interrelationships between weight loss, body fat distribution and sex hormones in pre- and postmenopausal obese women

Objectives. Relationships between regional body fat distribution and sex hormones as well as changes in sex hormones after weight loss were evaluated. Setting. All subjects were hospitalized in the Institute of Internal Medicine of the University of Verona. Subjects. Twenty-six premenopausal (age 33.7± 10.2 years) and 15 postmenopausal (age 57.9±5.9 years) obese women. Interventions. Body weight, body-mass index, waist and hip circumferences, visceral fat by computed tomography and sex hormones were evaluated before and after 4 weeks on a very low energy diet. Results. Body-mass index was higher in pre- than in postmenopausal women, although the difference was not significant. Total and free testosterone were significantly higher in the pre- than in the postmenopausal group (P<0.001). Significant negative correlations were found between age and total testosterone (r=?0.65; P<0.001), free testosterone (r=?0.54; P<0.001), androstenedione (r=?0.46; P<0.01) and urinary cortisol excretion (r=?0.50; P<0.01). A negative correlation was found between visceral fat and total testosterone (r=?0.41; P<0.01). After adjusting for age, the negative correlation between total testosterone and visceral fat encountered both in the subject group as a whole and in premenopausal women was no longer significant, whilst a significant negative association between visceral fat and sex hormone binding globulin (SHBG) (r=?0.56; P<0.001) was always found. When step-down regression analysis was used to evaluate the joint effect of age, menopausal status, and anthropometric and metabolic variables on sex hormones, age was the most powerful independent variable for predicting total testosterone, free testosterone and androstenedione levels, whilst menopausal status was the most powerful predictor of FSH and LH levels. Changes in hormones after VLED were analysed separately in pre- and postmenopausal women. None of the hormones changed significantly after VLED in the postmenopausal group, except for FSH values. LH, free testosterone and urinary cortisol excretion values decreased significantly after VLED in the premenopausal group. Conclusions. Our data show that age, to a greater extent than visceral fat, seems to be negatively associated with steroid sex hormones. Weight loss seems to be associated with changes in sex hormones only in premenopausal women.     

Obesity, regional body fat distribution, and the metabolic syndrome in older men and women

BACKGROUND: The metabolic syndrome is a disorder that includes dyslipidemia, insulin resistance, and hypertension and is associated with an increased risk of diabetes and cardiovascular disease. We determined whether patterns of regional fat deposition are associated with metabolic syndrome in older adults. METHODS: A cross-sectional study was performed that included a random, population-based, volunteer sample of Medicare-eligible adults within the general communities of Pittsburgh, Pa, and Memphis, Tenn. The subjects consisted of 3035 men and women aged 70 to 79 years, of whom 41.7% were black. Metabolic syndrome was defined by Adult Treatment Panel III criteria, including serum triglyceride level, high-density lipoprotein cholesterol level, glucose level, blood pressure, and waist circumference. Visceral, subcutaneous abdominal, intermuscular, and subcutaneous thigh adipose tissue was measured by computed tomography. RESULTS: Visceral adipose tissue was associated with the metabolic syndrome in men who were of normal weight (odds ratio, 95% confidence interval: 2.1, 1.6-2.9), overweight (1.8, 1.5-2.1), and obese (1.2, 1.0-1.5), and in women who were of normal weight (3.3, 2.4-4.6), overweight (2.4, 2.0-3.0), and obese (1.7, 1.4-2.1), adjusting for race. Subcutaneous abdominal adipose tissue was associated with the metabolic syndrome only in normal-weight men (1.3, 1.1-1.7). Intermuscular adipose tissue was associated with the metabolic syndrome in normal-weight (2.3, 1.6-3.5) and overweight (1.2, 1.1-1.4) men. In contrast, subcutaneous thigh adipose tissue was inversely associated with the metabolic syndrome in obese men (0.9, 0.8-1.0) and women (0.9, 0.9-1.0). CONCLUSION: In addition to general obesity, the distribution of body fat is independently associated with the metabolic syndrome in older men and women, particularly among those of normal body weight.     

The metabolic syndrome in obese postmenopausal women: relationship to body composition, visceral fat, and inflammation

The purpose of this study was to investigate whether aerobic fitness, body composition, body fat distribution, and inflammation are different in obese postmenopausal women with and without the metabolic syndrome (MS), and whether the severity of MS is associated with these characteristics. Fifty-eight women (age, 59 +/- 1 yr; body mass index, 33.0 +/- 0.6 kg/m2)completed testing of maximal aerobic capacity, body composition (fat mass, lean mass, and percent body fat), body fat distribution (sc and visceral fat areas, and regional adipocyte sizes), and inflammation (C-reactive protein, IL-6, and TNF-alpha,and their soluble receptors). Lean mass (44.4 +/- 0.9 vs. 41.2 +/- 0.9 kg; P < 0.05), visceral fat area (180 +/- 10 vs. 135 +/- 7 cm2; P <0.001), and plasma soluble TNF receptor 1 (sTNFR1; 860 +/- 25 vs. 765 +/- 42 pg/ml; P < 0.05) were higher in women with the MS(n = 27) than in those without the MS (n = 31). The number of MS components was directly related to weight, body mass index, fat mass, lean mass, visceral fat area, and plasma sT-NFR1. We conclude that obese older women with the MS are characterized by high lean mass, high visceral fat, and elevated sTNFR1, and the severity of the MS is associated with body composition, visceral adiposity, and inflammation.     

绝经后妇女体脂分布与Leptin水平变化的研究

目的　研究绝经后妇女体脂含量和分布指标与血清 Leptin水平变化间的关系。方法　收集 92例绝经前后妇女 ,依据绝经与否分为绝经前组 2 2例 ,绝经后组 70例。血清 Leptin及雌激素水平以放免法检测 ,同时测定其他参数。所得资料进行统计学处理。结果　 Leptin水平同体重指数、臂围等呈显著正相关。肥胖组 Leptin显著升高 ,与年龄、血压和性激素无关。多元逐步回归分析显示 ,BMI为影响 Leptin水平的主要因素 ,参与值达到 40 .0 9%。结论　绝经后妇女体脂分布发生了改变 ,呈“苹果”型 ,提示绝经后肥胖妇女体内存在 L eptin抵抗     

Lipid profile, BMI, body fat distribution, and aerobic fitness in men with metabolic syndrome

Obesity, impaired glucose tolerance, type 2 diabetes, hyperlipidemia, hypertension, and insulin resistance are wellknown components of metabolic syndrome and are associated to increased cardiovascular morbidity. The present study aimed to evaluate the relationships between cardiorespiratory fitness, body fat distribution, and selected coronary heart disease risk factors. A total of 22 untrained subjects affected by one or more features of metabolic syndrome and without clinical history of cardiovascular disease were studied. Nondiabetic subjects underwent an oral glucose tolerance test for glucose and insulin measurement; fasting glucose and insulin were measured in diabetic patients. Complete lipid profile, thyroid hormones, and thyroid-stimulating hormone were measured in all subjects. Basal energy expenditure and cardiorespiratory fitness were measured using a K4 analyzer. Cardiorespiratory fitness ( VO(2max)/kg) was assessed using a treadmill graded exercise test. Peak aerobic capacity ( VO(2max)/kg) was predicted by body fat distribution, insulin sensitivity index, and high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol ( p<0.001). A significant relationship was found between cardiorespiratory fitness ( VO(2max)/kg) and body mass index (BMI), insulin sensitivity index, and LDL cholesterol ( r=0.60, p<0.05; r=0.66, p<0.01 and r=0.54, p<0.05, respectively). Data demonstrated that aerobic fitness is related to metabolic parameters and to body fat distribution, and suggest that its modification may improve well-known predictors of coronary artery disease.     

Relationship between hormone replacement therapy use with body fat distribution and insulin sensitivity in obese postmenopausal women.

The aim of this study was to compare the effect of hormone replacement therapy (HRT) on insulin resistance and central adiposity in obese postmenopausal women. Forty-five obese postmenopausal women (16 HRT users and 29 nonusers), with a mean age of 56.6 +/- 5.3 years and duration of current, continuous HRT use of 4.7 +/- 2.9 years, were included in the study. Subjects were studied using oral glucose tolerance tests, euglycemic clamping, dual photon x-ray absorptiometry, computed tomography, doubly labeled water, and treadmill testing. Insulin sensitivity, total fat, visceral fat, subcutaneous abdominal fat, thigh muscle attenuation, daily physical activity energy expenditure, peak oxygen consumption (Vo(2)) were measured. HRT users had lower body weight (88.0 +/- 11.0 v 98.2 +/- 15.0 kg, P =.05), lower body mass index (33.1 +/- 3.5 v 36.8 +/- 5.2 kg/m(2), P =.05), lower fat mass (38.3 +/- 7.3 v 44.1 +/- 10 kg, P =.05), less visceral adipose tissue (157 +/- 47 v 211 +/- 81 cm(2); P =.05), and higher peak Vo(2) (21.1 +/- 4.6 v 17.6 +/- 2.2 mL/kg/min, P =.001) than nonusers. After adjustment for total fat, we noted a trend for decreased visceral adipose tissue in HRT users (P =.09). After adjustment for peak Vo(2), the decreased visceral adipose tissue persisted in HRT users (P <.01). Insulin sensitivity per kilogram of lean body mass did not differ between HRT users (0.51 +/- 0.22 mmol/kg/min) and nonusers (0.49 +/- 0.22 mmol/kg/min). It was concluded that obese postmenopausal women using HRT have a more favorable body composition and fat distribution pattern than nonusers. Although visceral adipose tissue is decreased in HRT users, insulin sensitivity does not differ between HRT users and nonusers.     

The association of body fat distribution with lifestyle and reproductive factors in a population study of postmenopausal women

We examined the cross-sectional association of fat distribution with a number of lifestyle and reproductive factors in a random sample of 40,980 postmenopausal women, aged 55 to 69 years. The relationship of weight history with current fat distribution was also explored. Body fat distribution, defined by the ratio of waist-to-hip circumferences (WHR), was most strongly related to body mass index (BMI). WHR was also significantly and negatively associated with physical activity, alcohol consumption, and education, and was significantly positively associated with age, cigarette smoking, and a number of reproductive factors, such as history of infertility, number of live births, age at first live birth, and replacement estrogen use. WHR was not related to past BMIs, after adjusting for current body mass. The best-fit final regression model included (beta +/- s.e.) age (0.003 +/- 0.0001), BMI (0.02 +/- 0.0005), a curvilinear term for BMI (-0.0002 +/- 0.00001), greater than high school education (-0.007 +/- 0.001), cigarette smoking (0.02 +/- 0.001), alcohol drinker (-0.005 +/- 0.001), and number of live births (0.001 +/- 0.0002). The model R2 was 0.21. BMI (R2 = 0.18) and age (R2 = 0.02) accounted for most of the variation in WHR. The association of these lifestyle and reproductive factors with WHR suggests that the deposition of fat in the abdominal versus the gluteal region may be influenced somewhat by factors other than overall adiposity and genetics.     

Estrogen treatment and body fat distribution are involved in corticotropin and cortisol response to corticotropin-releasing hormone in postmenopausal women

To assess the effect of transdermal estrogen substitution on the hypothalamic-pituitary-adrenal (HPA) axis responsiveness/sensitivity and the impact of the antrophometric characteristics on these parameters, 20 postmenopausal women seeking treatment for the relief of postemenopausal symptoms were studied. They received transdermal 50 microg/d estradiol for 12 weeks (estrogen replacement therapy [ERT]). Patients were classified as low waist-to-hip ratio (WHR) (peripheral fat distribution women; n = 12) and high WHR (central fat distribution women; n = 8) according to the cut-off value of 0.85. Plasma hormone and lipid concentration were assessed at baseline and after 12 weeks of treatment. Results were compared with a group of 8 placebo-treated patients who served as controls. Corticotropin (ACTH) and cortisol (F) were expressed as fasting values, area under the curve (AUC), and time course over 90 minutes after corticotropin-releasing hormone (CRH) intravenous (IV) bolus (1 microg/kg body weight [BW]). Adrenal sensitivity to CRH stimulus was expressed as time course over 90 minutes and AUC of the F/ACTH molar ratio. The plasma F levels in response to ACTH stimulation did not change after ERT; however, a highly significant improvement of adrenal sensitivity was observed (P <.01). In fact, estrogen treatment significantly decreased the amount of ACTH produced after CRH stimulation, both as absolute time course and AUC (P <.01). No significant change was observed in controls. Considering body fat distribution, the high WHR group showed higher ACTH (P <.01), lower F/ACTH values, and superimposable F plasma values compared with the low WHR group. Estrogen treatment induced a significant ACTH reduction after CRH (P <.01) only in the high WHR group, whereas cortisol response was similar in both groups both before and after treatment. A significant negative correlation was found between WHR and adrenal sensitivity before treatment. ERT significantly improved adrenal sensitivity only in the low WHR group (P <.01). These data suggest that different mechanisms can prevail in the control of the HPA axis in menopause. Estrogens could exert different effects on the hypothalamic-pituitary axis, as well as on adrenal function, and these changes seem to be partially dependent on the pattern of body fat distribution.     

Racial differences in body fat distribution among reproductive-aged women

We examined the influence of race/ethnicity on body fat distribution for a given body mass index (BMI) among reproductive-aged women. Body weight, height, and body fat distribution were measured with a digital scale, wall-mounted stadiometer, and dual-energy x-ray absorptiometry, respectively, on 708 healthy black, white, and Hispanic women 16 to 33 years of age. Multiple linear regression was used to model the relationship between race/ethnicity and different body fat distribution variables after adjusting for BMI, age at menarche, and demographic and lifestyle variables. For a given BMI, white women had the highest total fat mass (FM_total), trunk fat mass (FM_trunk), and leg fat mass (FM_leg), whereas Hispanic women had the highest percentage of FM_trunk (%FM_trunk) and trunk-to-limb fat mass ratio (FMR_{trunk-to-limb}). Conversely, black women had the lowest FM_total, FM_trunk, percentage body fat mass (%FM), %FM_trunk, and FMR_{trunk-to-limb}, and the highest percentage of FM_leg. The %FM was similar in whites and Hispanics and lower in blacks. The race × BMI interactions were significant for almost all of the body fat distribution variables. Increasing in differences with increasing BMI were apparent between blacks and whites in FM_trunk, %FM_trunk, FMR_{trunk-to-limb}, %FM_leg, and %FM, and between blacks and Hispanics in FM_trunk, %FM_trunk, FMR_{trunk-to-limb}, and FM_leg. In summary, the distribution of body fat for a given BMI differs by race among reproductive-aged women. These findings raise questions regarding universally applied BMI-based guidelines for obesity and have implications for patient education regarding individual risk factors for cardiovascular disease and metabolic complications.     

Effects of fat mass and body fat distribution on resting metabolic rate in the elderly

The aim of the present study was to investigate the relationship between resting metabolic rate (RMR) and fat-free mass, fat mass, and body fat distribution in 164 women (age 60 to 85 years; body mass index [BMI], 18.5 to 35.6 kg/m(2)) and 98 men (age 60 to 85 years; BMI, 18.3 to 36.5 kg/m(2)). After an overnight fast, RMR was assessed by indirect calorimetry and body composition by bioelectrical impedance analysis. Waist-to-hip ratio (WHR) was used to determine fat distribution. Results from linear regression analysis showed that most of the variance in RMR could be attributed to fat-free mass in women (R(2) = 0.54) and men (R(2) = 0.44), respectively. Fat mass explained an additional 3% and 2% of the variability in RMR in women and men, respectively. In stepwise multiple regression analysis, considering body composition and fat distribution, only fat-free mass and WHR were significant predictors of RMR in both sexes. In addition to fat-free mass, in women 6% and in men 8% of the variability in RMR was attributable to WHR. Grouping subjects according to their WHR, RMR, and RMR adjusted for fat-free mass and fat mass showed a significant increase with increasing WHR in both sexes. Results indicate that RMR not only depends on fat-free mass but also is influenced by fat mass, especially by fat distribution. These findings support our hypothesis of an elevated RMR with increasing abdominal body fat as a direct consequence of its greater metabolic activity.     

Racial differences in subcutaneous and visceral fat distribution in postmenopausal black and white women

Most studies examining racial disparities in abdominal fat distribution have focused on premenopausal women. The purpose of this report was to determine if racial differences exist in the abdominal fat distribution in postmenopausal white and black women. Fifty-four women (33 white and 21 black) were scanned by magnetic resonance imaging (MRI) to determine abdominal fat distribution, were measured by hydrostatic weighing for percent body fat, and had their fasting blood lipids, glucose, and insulin levels measured. These women were matched for age (mean age, 53.5 +/- 0.9 years) and percent body fat (black: 39.6% +/- 2.3%, white: 37.3% +/- 1.2%). When adjusted for total body fat mass and hormone replacement therapy (HRT), total abdominal fat (white: 10,352.1 +/- 535.2, black: 11,220.4 +/- 670.1 cm(3)) was not statistically different between groups, but the visceral fat content was significantly higher in the white women (white: 2,943.5 +/- 220.4, black: 2,332.6 +/- 176.1 cm(3)). The percent visceral fat was also higher in these women (white: 30.5% +/- 1.3%, black: 22.1% +/- 1.6%, P <.01). Subcutaneous adipose tissue (SAT) was significantly higher in the black women (white: 7,408.6 +/- 450.2, black: 8,887 +/- 563.1 cm(3), P <.05). No significant differences were found in the insulin concentrations or the blood lipid profile of these women. Regardless of race, visceral fat was a significant predictor of log triglyceride, low-density lipoprotein-cholesterol (LDL-C), cholesterol/LDL-C, insulin levels, and insulin resistance. Race was only found to contribute to 8% of the variability of LDL-C. HRT use had no effect on abdominal fat distribution or the blood lipid profile in this cohort of women. In conclusion, disparities in abdominal fat distribution between black and white women continue to exist in the early postmenopausal years, and the regression results indicate that the absolute amount of visceral fat, and not the relative amounts of visceral fat, is the best predictor of the blood lipid profile and insulin sensitivity. HRT use did not result in differences in abdominal fat distribution in these women. Factors, such as genetics and lifestyle, must play a larger role in explaining the increased health risk in black women.     

Excess body fat distribution and glucose homeostasis in obese Arab women

The relationship of body fat distribution to glucose intolerance and non-insulin-dependent diabetes mellitus in Arab women was studied in 102 obese non-diabetic and 40 obese women with diabetes. The obese women underwent a glucose tolerance test. Linear regression analysis revealed a significant correlation between the waist/hip ratio and the plasma glucose concentration at 120 min. When divided into two groups according to the median of their waist/hip ratio (0.815), obese women without history of diabetes but with high waist/hip ratio (0.86 +/- 0.07, mean +/- SD) had significantly higher prevalence of glucose intolerance and of diabetes mellitus than those with the low ratio (0.78 +/- 0.03, chi 2 = 9.32, p less than 0.001). The highest ratio (0.89 +/- 0.06) was observed in the obese women with known diabetes mellitus.     

Influence of body fat content and distribution on variation in metabolic risk

OBJECTIVES: Several reports indicate that the body fat compartments, especially ip fat, predict metabolic risk better than total body fat. The objective of the study was to determine whether this can be confirmed and generalized throughout the population. PARTICIPANTS: A representative sample of 1934 Black and White women and men of the Dallas Heart Study participated in the study. DESIGN: We measured the fat in total body, trunk, and lower body with dual-energy x-ray absorptiometry and in abdominal compartments (sc, ip, and retroperitoneal) with magnetic resonance imaging. Other measurements included body mass index (BMI), waist circumference, blood pressure, plasma lipids, glucose, insulin (including homeostasis model), and C-reactive protein. RESULTS: In all groups, total body fat correlated positively with key metabolic risk factors, i.e. homeostasis model, triglyceride/high-density lipoprotein-cholesterol ratios, C-reactive protein, and blood pressure; however, it explained less than one third of the variability of all the risk factors. After adjustment for total body fat, truncal fat conferred additional positive correlation with risk factors. Furthermore, with multivariable regression analysis, ip fat conferred independent correlation with plasma lipids beyond a combination of other compartments including truncal fat. Still, except for insulin levels, all combinations including ip fat still explained less than one third of the variability in risk-factor levels. Conversely, lower body fat correlated negatively with risk factors; i.e. lower body fat appeared to offer some protection against risk factors. CONCLUSIONS: Body fat distribution has some influence on risk factors beyond total body fat content. Both waist circumference and BMI significantly predicted risk factors after adjustment for total body fat, and for clinical purposes, most of the predictive power for men was contained in waist circumference, whereas for women, BMI and waist circumference were similarly predictive. Finally, even though the correlations between combined body fat parameters and risk factors explained only a portion of the variation in the latter, the average number of categorical metabolic risk factors increased progressively with increasing obesity. Hence, obesity seemingly has more clinical impact than revealed in these correlative studies.