Visceral Fat Distribution Research Articles

The reduction of dietary sucrose improves dyslipidemia, adiposity, and insulin secretion in an insulin-resistant rat model

Objective The purpose of the present work was to investigate whether changes in the type of carbohydrate in the diet are able to improve and/or reverse hyperlipemia, impaired glucose homeostasis, and insulin secretion from β-cells induced in rats by chronically feeding a high sucrose intake. Methods For 30 wk male Wistar rats received a sucrose-rich diet (63% w/w) or a control diet in which sucrose was replaced by starch. After this period, the sucrose-fed animals were randomly divided into two groups: the first group continued with this diet up to 42 wk and the other received the same diet but with a 20% reduction in the amount of sucrose and the rest of the carbohydrate being replaced by starch. Rats were fed with this diet for the next 12 wk. Results The reduction of the amount of sucrose in the diet showed a substantial improvement ( P < 0.05) of dyslipidemia associated with an amelioration of “in vivo” very low-density lipoprotein-triacylglycerol secretion and triacylglycerol removal rate from the circulation. Glucose homeostasis and glucose-induced insulin release from β-cells were improved ( P < 0.05), although these values did not reach those observed in rats fed a control diet. Visceral adiposity was also significantly reduced ( P < 0.05). Conclusion These data are consistent with the suggestion that the composition of the diet could contribute to improvements in dyslipidemia, insulin resistance, and adiposity by direct effects on the lipid metabolism and insulin action and indirectly through the reduction of visceral fat mass and distribution.

Dehydroepiandrosterone Behavior and Lipid Profile in Non-Obese Women undergoing Abdominoplasty

The aim of this study was to determine any change in dehydroepiandrosterone (DHEA) and lipid profile in non-obese women after abdominoplasty. An auto-controlled clinical trial was carried out. 9 women aged 35 to 40 years with BMI 22-25 kg/m2 were studied. Basal lipid profile and DHEA were performed and repeated 1 month postoperatively. Statistical analysis used Wilcoxon signed-ranks test (two-tailed). Weight of resected specimen was 606.11 +/- 143.4 grams. No significant changes were observed in high-density cholesterol (48.0 +/- 9.6 vs 48.8 +/- 11.0 mg/dl; P=0.106) or in triglycerides (119.2 +/- 50.9 vs 148.4 +/- 45.8 mg/dl; P = 0.139). Significant increases were obtained in DHEA (3.69 +/- 3.05 vs 11.09 +/- 6.3 ng/ml; P<0.008), low-density cholesterol (LDL) (87.4 +/- 23.5 vs 108.5 +/- 28.3 mg/dl; P<0.008 and total cholesterol (155.1 +/- 30.6 vs 186.6 +/- 33.1 mg/dl; P<0.008). Excision of subcutaneous abdominal fat in studies 1 month later increased DHEA, whose role is controversial in visceral fat distribution, and increased LDL cholesterol and total cholesterol, both risk markers for cardiovascular illness.

“Buffalo” hump in nonalcoholic fatty liver disease

I read with interest the recent article by Cheung et al.1 regarding the impact of fat distribution, as estimated by several anthropometric parameters, on the severity of nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome in obese NAFLD patients. Notably, they found that dorsocervical lipohypertrophy (“buffalo” hump) was the single greatest predictor of the histological severity of NAFLD, whereas waist circumference was the greatest predictor of the severity of metabolic syndrome.1 Dorsocervical lipohypertrophy (DCL) was diagnosed only clinically but no quantitative measure (for example, ultrasound imaging) was used for diagnosing the “hump” at the base of the neck. Obviously, this is a major limitation of the study. Additionally, it is conceivable that the differential impact of DCL and waist circumference on the severity of NAFLD histology and metabolic syndrome is simply due to the fact that they are only indirect and crude indices of abdominal visceral fat distribution.2 A direct and more accurate measure of abdominal visceral fat, obtained by computed tomography or magnetic resonance imaging,2 would be useful to explore this issue adequately. However, the authors have interestingly shown that DCL, which is commonly seen in Cushing's syndrome, is a highly prevalent condition (28.5%) in obese NAFLD patients,1 thus suggesting an underlying subclinical hypercortisolism in NAFLD. Regarding this, recent studies have consistently shown a subclinical hypothalamo-pituitary-adrenal (HPA) axis dysfunction in NAFLD. Westerbacka et al.3 reported that obese men with higher liver fat content (as evaluated by magnetic resonance imaging spectroscopy) have a selective increase in 24-hour urinary excretion of 5-beta-reduced cortisol metabolites and a lower ratio of urinary cortisol/cortisone metabolites than men with lower liver fat content. Saruc et al.4 found that postmenopausal women with NAFLD, as assessed by ultrasound, have higher plasma dehydroepiandrosterone levels than controls. Others have shown that obese individuals5 and overweight type 2 diabetic patients6 with ultrasonographically diagnosed NAFLD have higher 24-hour urinary free cortisol excretion and postdexamethasone suppression cortisol concentrations than nonsteatotic controls. More importantly, we have recently demonstrated that overweight patients with biopsy-proven NAFLD have a subclinical, chronic HPA axis activation (as reflected by the increased, albeit still normal, 24-hour urinary free cortisol values and the blunted suppression of cortisol levels by 1.0 mg-dexamethasone with normal serum corticosteroid-binding globulin concentrations) that is correlated to the histopathological severity of NAFLD (that is, necro-inflammatory grade and fibrosis stage) independently of multiple potential confounders, including insulin resistance and metabolic syndrome components.7 Overall, therefore, the evidence from these studies,3-7 although only correlative in nature, suggests the hypothesis that overweight/obese NAFLD patients have a subtle HPA axis dysfunction that is strongly correlated with the severity of NAFLD histology, leading to subclinical cortisol overproduction that might be implicated in the development/progression of NAFLD. Future prospective and interventional (by using a cortisol inhibitor or specific 11beta-hydroxysteroid dehydrogenase-type 1 inhibitors) studies are obviously needed to validate this hypothesis and to better understand the underlying biological mechanisms linking HPA axis dysfunction to the development of NAFLD. Giovanni Targher M.D.*, * Section of Endocrinology, Department of Biomedical and Surgical Sciences, University Hospital, Verona, Italy.

Automated Quantification of Body Fat Distribution on Volumetric Computed Tomography

To develop a computerized method to automatically quantify visceral and subcutaneous fat distribution within the abdomen and pelvis on volumetric computed tomographic (CT) images. Given the slices of interest, the algorithm automatically delineates a contour that separates the visceral fat from the subcutaneous fat on each slice. Explicitly, starting with extraction of the body perimeter, radii at a fixed angle increment are drawn from the perimeter to the center of the body. Along each radius, intensity profile is analyzed to determine the point on the subcutaneous fat layer that is closest to the body center (inner point). All inner points are then connected to form an inner contour, and a specific smoothing algorithm is subsequently applied to correct suboptimal results. Pixels having HU values between -190 and -30 are considered fat pixels. This procedure is repeated on each of the slices of interest. The visceral and subcutaneous fat volumes computed automatically were compared with those after the radiologist's adjustments. Ratios of volumetric visceral fat-to-total fat and visceral fat-to-subcutaneous fat were compared on average and with single-slice measurements obtained at L4 and L5 vertebral body levels. Subcutaneous and visceral fat were automatically segmented using this algorithm on 419 axial CT slices in 9 CT scans (patients) within the abdomen and pelvis. The overall average percentage difference between the automated segmentation and the segmentation edited by the radiologist were 1.54% for the visceral fat and 0.65% for the subcutaneous fat. Preliminary results have shown that total compartmental fat, including visceral and subcutaneous fat, can be automatically and accurately segmented on volumetric CT.

Metabolic syndrome and lower urinary tract symptoms secondary to benign prostatic hyperplasia

Increasing evidence recently has pointed toward a relationship between lower urinary tract symptoms (LUTS) and the presence of metabolic syndrome. This relationship has been supported by recent epidemiologic findings. Possible pathophysiologic links also have been proposed to explain the relationship between these two syndromes. The increasing prevalence of obesity in the United States makes this an increasingly relevant problem. Animal studies support a link between autonomic nervous system (ANS) overactivity and the development of urinary symptoms, low bladder compliance, compensatory prostatic hyperplasia, and blockage of the same using alpha-blockade. There appears to be a significant link between ANS overactivity as part of the metabolic syndrome and LUTS secondary to benign prostatic hyperplasia (BPH). However, it is unlikely that ANS overactivity could be responsible for the development of LUTS. Rather, ANS overactivity plays a key role in increasing the severity of LUTS above an intrinsic basal intensity that is determined by the genitourinary anatomic/pathophysiologic characteristics of each BPH patient. This paper defines metabolic syndrome as a collection of abnormalities, including being overweight (visceral abdominal fat distribution), dyslipidemia, hypertension, impaired glucose metabolism, elevated C-reactive protein (chronic inflammation), and autonomic-sympathetic overactivity, with insulin resistance as the hypothesized underlying pathogenic mechanisms.

Heart positive: Design of a randomized controlled clinical trial of intensive lifestyle intervention, niacin and fenofibrate for HIV lipodystrophy/dyslipidemia

Dyslipidemia and insulin resistance occur in a large proportion of HIV-infected patients treated with highly active antiretroviral therapy (HAART); anthropomorphic changes, such as lipoatrophy and central obesity, occur in a subset of patients. This cluster of clinical features, which is termed HIV lipodystrophy, places patients at increased risk for cardiovascular disease. Currently, there is no consensus on the appropriate therapy for the management of HIV lipodystrophy for which the underlying defects are enhanced lipolysis, impaired fat oxidation, increased hepatic VLDL-triglyceride synthesis and secretion, and impaired disposal of intestinally-derived lipoprotein-triglycerides. We describe the design of a randomized, placebo-controlled trial to compare the effects of usual care to diet, exercise and lipid-lowering drugs on lipid profiles of patients with HIV lipodystrophy. The trial will randomize 200 patients into five groups. Outcomes of usual care, diet and exercise alone or in combination with niacin, fenofibrate or both medications will be compared after six months. Unique aspects of the design include an interactive Internet Diet Management system to increase ATP-III recommended dietary compliance for metabolic syndrome, and a supervised program of aerobic and resistance exercises. The study is powered to detect a 20% decrease in triglycerides with the lifestyle intervention and an additional 20% improvement with the addition of niacin and/or fenofibrate. Secondary outcomes include assessment of lipid profile changes, LDL and HDL particle size, plasma cholesterol ester transport protein activity, visceral and subcutaneous fat distribution, glucose tolerance, insulin resistance, and leptin and adiponectin levels.

Effects of growth hormone on insulin resistance and atherosclerotic risk factors in obese type 2 diabetic patients with poor glycaemic control

SummaryObjective We aimed to evaluate the combined effects of GH treatment and diet restriction on lipolysis and anabolism, insulin resistance and atherosclerotic risk factors in obese patients with type 2 diabetes mellitus (T2DM).Subjects This randomized, double‐blind, placebo‐controlled study included 24 obese T2DM patients (male : female = 12 : 12, mean age 53·7 ± 7·2 years) with poor glycaemic control (fasting plasma glucose 10·673 ± 1·121 mmol/l, HbA1C 9·9 ± 2·3%). Sixteen of these patients were treated with recombinant human GH (1–1·5 units/day, 5 days/week) while undergoing diet restriction and exercise for 12 weeks.Methods Anthropometric and bioelectrical impedance measurements were undertaken to determine the lean body mass and total body fat. Computed tomography (CT) was performed to estimate visceral and subcutaneous fat distribution at the umbilicus level and the muscle area of the midthigh. Insulin resistance was measured by the insulin tolerance test (ITT) and by the homeostasis model assessment of insulin resistance (HOMA‐IR).Results The ratios VSR (visceral fat area/subcutaneous fat area) and VMR (visceral fat area/thigh muscle area) were significantly decreased in the GH‐treated group compared to the control group. An increase in lean body mass was observed in the GH‐treated group. Levels of total cholesterol, triglyceride, free fatty acid (FFA), fibrinogen, and plasminogen activator inhibitor‐1 (PAI‐1) were significantly decreased after GH treatment. Fasting glucose levels decreased similarly (P &lt; 0·05 anova) in both groups during the treatment period. Fasting C‐peptide levels significantly increased, whereas insulin levels significantly decreased, in the GH‐treated group, but no changes were observed in the control group. The insulin sensitivity index (ISI) was significantly increased in the GH‐treated group (1·3 ± 1·4 vs. 1·9 ± 1·0%/min, P &lt; 0·05).Conclusions GH treatment in obese T2DM patients with poor glycaemic control is beneficial in decreasing the amount of visceral fats, and may therefore result in improvements in insulin resistance, atherosclerotic risk factors and dyslipidaemia.

Relationship of body fat distribution by waist circumference, dual-energy X-ray absorptiometry and ultrasonography to insulin resistance by homeostasis model assessment and lipid profile in obese and non-obese postmenopausal women

Objective. To correlate body fat distribution evaluated by waist circumference, dual-energy X-ray absorptiometry and ultrasonography to insulin resistance and lipid profile in obese and non-obese postmenopausal women.Methods. We studied 40 obese and 47 non-obese postmenopausal women, assessing obesity by measuring waist circumference and fat tissue using dual-energy X-ray absorptiometry and ultrasonography, and examining their correlation with metabolic parameters: insulin resistance as determined by the homeostasis model assessment technique (HOMA-IR) and lipid profile including triglycerides (TG), total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), very-low-density lipoprotein, lipoprotein(a) (Lp(a)) and apoplipoprotein A-I (Apo A-I).Results. There was no difference in lipid profile between the two groups. Insulin resistance was the metabolic disturbance of highest prevalence in the obese group, evaluated by HOMA-IR (obese: 3.38 ± 2.2; non-obese: 1.20 ± 0.7; p < 0.001). Obesity was not a confounding factor in linear regression analyses among HOMA-IR, HDL-C, TG, Lp(a), Apo A-I and the methods used to measure body fat distribution. Waist circumference was the method that best explained HOMA-IR (R2 = 34.9%, p < 0.001) and TG concentration (R2 = 10.9%, p = 0.002). HDL-C presented a positive association with subcutaneous fat evaluated by ultrasonography (R2 = 12.5%, p < 0.001). Obesity was a confounding factor in multiple regression analyses between TC and LDL-C, when related to abdominal fat evaluated by ultrasonography, and resulted in a positive association among the obese and a negative association among the non-obese women. The sensibility of this method was related to the quantity of fat in the visceral region.Conclusions. Waist circumference showed the highest association with insulin resistance. Fat distribution evaluated by dual-energy X-ray absorptiometry and ultrasound was also associated with insulin resistance, but with lower intensity. The relationship of visceral fat distribution evaluated by ultrasound to TC cholesterol and LDL-C showed opposed results between obese and non-obese menopausal women.

Corrigendum to “The effects of atypical antipsychotics on visceral fat distribution in first episode, drug-naive patients with schizophrenia”[Life Sciences 74 (2004) 1999–2008

Corrigendum to “The effects of atypical antipsychotics on visceral fat distribution in first episode, drug-naive patients with schizophrenia”[Life Sciences 74 (2004) 1999–2008

The effects of atypical antipsychotics on visceral fat distribution in first episode, drug-naive patients with schizophrenia

The aim of this study was to determine the location of antipsychotic-induced weight gain in drug naı̈ve, first episode patients with schizophrenia. Various fatness and fat distribution parameters (by Computerized Tomography scanning and anthropometry) and 1600 hr plasma cortisol were measured in 19 (15 men and 4 women) subjects with schizophrenia (mean age = 31.0 years; mean body mass index [BMI] = 24.6 kg/m 2) and an equal number of age- and sex- matched controls (mean age = 32.6 yr; mean BMI = 23.0 kg/m 2). Patients were then given either olanzapine or risperidone. Sixteen patients were re-tested following a treatment period lasting approximately 6 months. Patients with schizophrenia, had significantly more intra-abdmonial fat [IAF] (116.8 ± 20.2 cm 2 vs. 38.0 ± 4.8 cm 2, respectively; t = 3.80, df = 18, p < 0.0001) and had higher levels of plasma cortisol (360.2 ± 49.6 nmol/L vs. 192.7 ± 19.7 nmol/L, respectively; t = 3.13, df = 18, p < 0.003) than appropriately matched control subjects. Treatment with atypical antipsychotics did not result in a significant increase in IAF (116.8 ± 20.2 cm 2 vs. 131.7 ± 20.9 cm 2; p = NS) though visceral fat stores still remained significantly higher than those seen in controls (38.0 ± 4.8 cm 2) (F = 9.34; df = 2, 51; p < 0.0003). However, plasma levels of cortisol did significantly decrease (360.2 ± 49.6 nmol/L ± vs. 316.2 ± 48.4 nmol/L; p < 0.05). Pre-treatment levels of IAF did not differ between those who received risperidone and those who were given olanzapine (123.0 ± 35.9 cm 2 vs. 113.1 ± 15.7 cm 2, respectively; t = 0.20, df = 16, p < 0.84). The increase in IAF did not differ between those given risperidone and those who received olanzapine (26.9 ± 12.1 cm 2 vs. 18.24 ± 11.44 cm 2, respectively; t = 0.50, df = 16, p < 0.63). Patients with drug naı̈ve, first episode, schizophrenia have higher levels of visceral fats stores as compared to matched control subjects. Treatment with atypical antipsychotics does not result in a significant increase in IAF distribution.

Size and Shape Modifications in Sardinian Adolescent Girls

In females, menarche is the defining moment of puberty, the period of life when the greatest body changes occur. In the present study, the metric and morphological variations associated with sexual maturation are defined in 155 Sardinian girls (10-17 years) and the role of some potentially influential variables is discussed: age, age at menarche and time since menarche. We studied thirty-eight anthropometric variables, the fat-free mass and the fat mass estimated by Bioelectrical Impedance Analysis. Statistical analyses were performed to evaluate the difference between pre- and post-menarcheal girls of the same age (Student's t-test) and to evaluate the different role played by the variables (principal components analysis, cluster analysis, multiple regression). The results demonstrate that the body dimensions of the adolescent girls mainly increase in concomitance with sexual maturation. The age at menarche influences the fat mass but not the distribution of visceral and subcutaneous fat. The time since menarche has also no effect on the distribution of subcutaneous fat.

단층촬영법에 의한 한국 성인의 성별, 연령 그리고 과체중 분류에 따른 복부부위의 체지방 분포의 차이

This study was performed to compared of subcutaneous and visceral fat distribution according to sex, age and overweight. The subjects were composed of 234(male:114, female：120) Korean adult men and women who were 20-81 years old. Abdominal fat depots were evaluated by computed tomography at one abdominal level. The population sample was categorized according to sex, age( age intervals : 20-39, 40-59, 60 more yr) and body mass index(BMI≤26 and BMI〉26.1; weight/hight2). The results were as follows： 1. Total fat and visceral fat area at abdominal level increased with aging in both male and female group. However Subcutaneous fat area decreased during aging in male group, and increased in female group. 2. 20-39 yr age group had higher subcutaneous fat area than the other groups, However Over the age of 60 had higher visceral fat area than the other groups in both male and female group. 3. The rate of S:V at abdominal level decreased during aging in both male and female. 4. Visceral fat area at abdominal level increased with aging in both male and female group by BMI26.1, However Subcutaneous fat area was no difference among three group in female, and increased during aging in male. 5. Subcutaneous fat and visceral fat area at abdominal level increased during aging in both male and female group by BMI≥26.

Effects of growth hormone secretion on body composition in patients with Crohn's disease.

Crohn's disease is a multisystem disorder characterized by chronic intestinal inflammation. Accumulation of mesenteric fat occurs in patients with Crohn's disease, although the mechanisms underlying site-specific changes in adipose deposition are unclear. To investigate whether there are alterations in site-specific adipose deposition in patients with Crohn's disease and to determine hormonal influences that may underlie such changes, we investigated body composition and serum hormone levels in 20 men with Crohn's disease (mean age, 45 +/- 2 yr) and 20 age-, gender-, and body mass index-matched normal controls (mean age, 43 +/- 3 yr). None of the Crohn's patients was receiving glucocorticoid therapy. Subjects underwent hourly GH sampling for 12 h beginning at 2000 h and fasting serum IGF-I and testosterone measurements. Body composition was assessed by quantitative computed tomography of the abdomen and bioelectrical impedance analysis. In the Crohn's disease and control subjects, mean serum GH levels were 1.07 +/- 0.2 and 1.7 +/- 0.2 ng/ml (P = 0.06), serum IGF-I levels were 162.7 +/- 10.5 and 194.8 +/- 15.7 ng/ml (P = 0.1), and serum testosterone levels were 489 +/- 33 and 514 +/- 38 ng/ml (P = NS), respectively. Percentage body fat was significantly higher in the Crohn's patients (21 +/- 0.8% vs. 17.7 +/- 0.9%, respectively; P = 0.013). Intraabdominal fat (IAF) was significantly higher in the Crohn's subjects vs. controls (115 +/- 11 vs. 69 +/- 7 cm(2), respectively; P = 0.001). The ratio of intraabdominal to total body fat was higher in the Crohn's subjects than in the controls (0.4 +/- 0.1 vs. 0.3 +/- 0.1, respectively; P = 0.025). Subcutaneous fat area was similar in the two groups. IAF was higher in Crohn's patients even when controlling for testosterone and mean serum GH. Mean serum GH contributed independently to the differences in IAF (P = 0.001). The ratio of IAF to total body fat remained higher in the Crohn's subjects when controlling for serum testosterone, but was no longer significant in a model that also included IGF-I and mean serum GH. GH levels contributed independently to the differences in the intraabdominal to total body fat ratio (P = 0.02). In the Crohn's patients, serum GH correlated negatively with intraabdominal and total body fat and the ratio of intraabdominal to total body fat. Crohn's disease is associated with an increase in central fat accumulation, with more IAF and a higher ratio of intraabdominal to total body fat compared with controls. Although serum GH levels were similar in the two groups, GH contributed significantly to the abdominal fat measurements. These data show that GH has an important role in modulating visceral fat distribution in patients with Crohn's disease.

Body composition, visceral fat distribution and fat oxidation in postmenopausal women using oral or transdermal oestrogen

Objectives: The aim of this study was to observe hysterectomized postmenopausal women (without progestogen, which could interfere in the results), using oral-conjugated oestrogen 0.625 mg daily ( n=13) or 17β-estradiol transdermal patches delivering 50 μg daily ( n=10) during 12 months, and to evaluate the treatment effects on body composition, visceral fat distribution, energy expenditure and substrate oxidation. Methods: We studied 23 postmenopausal women using oral-conjugated oestrogen (Premarin) 0.625 mg daily ( n=13) or transdermal oestrogen patches (Systen TTS) 50 μg daily ( n=10). Body composition was measured by DEXA, visceral adipose tissue areas were measured by abdominal computed tomography, and energy expenditure, fat oxidation and carbohydrate oxidation were measured by indirect calorimetry (Deltatrac Metabolic Monitor). Results: There were: (1) a decrease in IGF-I and an increase in GH levels in the oral group and no change in the transdermal group; (2) a increase in lean body mass in the transdermal group and a decrease in the oral group; (3) a increase in total body fat mass in the oral group and no change in the transdermal group; (4) an increases in total bone mass and in total bone mineral density in the transdermal group and no change in the oral group; (5) an increase in lipid oxidation in the transdermal group and a decrease in the oral group, and (6) no significantly change about weight, visceral adipose tissue areas and energy expenditure in both groups. Conclusions: The administration route of oestrogen replacement therapy in postmenopausal women confers distinct and divergent effects on body composition and substrate oxidation during 12-months treatment.

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 cm3) 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 cm3). 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 cm3, 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. Copyright 2003, Elsevier Science (USA). All rights reserved.

Association between nonalcoholic fatty liver, markers of obesity, and serum leptin level in young adults

OBJECTIVES: The aim of the present study was to clarify the risk factors for nonalcoholic fatty liver in young adults. METHODS: One thousand two hundred two students, aged 18–21 yr, received matriculation health examinations, including measurements of body mass index and percent body fat and determination of serum levels of ALT at Nagasaki University in 1998. One hundred twenty-nine were found to have borderline or elevated levels of serum ALT, and 105 of the 129 students (75 men and 30 women) were subjected to further analysis for the presence of fatty liver using ultrasonography, by which both the degree of steatosis and the abdominal wall fat index (AFI) corresponding to the ratio of visceral to s.c. adipose tissue (V/S ratio) were evaluated, in addition to determination of the serum level of leptin. RESULTS: Of 105 students, 74 (70%) had fatty liver. The incidence of moderately to severely fatty liver was significantly higher in men than in women. In parameters related to obesity, the close correlation between body mass index and percent body fat was observed in both sexes. The serum level of leptin correlated well with percent body fat and AFI (V/S ratio) in women, whereas it did not correlate with AFI (V/S ratio) in men. Multiple logistic regression analysis indicated that AFI (V/S ratio) was the only independent risk factor for fatty liver in both sexes. CONCLUSIONS: These results suggest that visceral fat distribution is a key risk factor for nonalcoholic fatty liver in young adults.

Obesity, cytokines and endothelial dysfunction: a link for the raised cardiovascular risk associated with visceral obesity.

Obesity (defined as a BMI >30 kg/m 2 has increased at an alarming rate over recent years and is now a worldwide public health problem. Obesity is a common condition in every continent. National surveys in the United States have shown a prevalence of obesity of 20% in men and 25% in women (1); the striking increase in prevalence in the last 2 decades of the past century also indicates that population-wide increase in obesity may occur over a short period of time. Data collected for the MONICA study indicate that more than half of the adult population between 36-65 yr of age in Europe are either overweight or obese (2). Although physicians are familiar with the concept of obesity, few of them see it as a real disease. For reasons that are not fully known, obesity is associated with an increased risk of heart disease, Type 2 diabetes and certain forms of cancer (3). In the Framingham Study, the risk of death within 26 yr increased by 2% for each extra pound (0.45 kg) increase in weight between the ages of 50-62 yr. This evidence should convey the due attention to the morbidity and mortality associated with more modest degrees of overweight and the detrimental effect of intra-abdominal fat. The intra-abdominal visceral deposition of adipose tissue, which characterizes upper body obesity, is a major contributor to the development of hypertension, insulin resistance, Type 2 diabetes and dyslipidemia. As a corollary, the role of visceral fat may be more complex than suspected because even people who are not obviously overweight may still have disproportionately too much fat with the result of a predisposition toward atherosclerotic disease. We hypothesize that inappropriate cytokine secretion from adipose tissue plays a role in the increased cardiovascular risk associated with obesity and visceral fat distribution.

Aging Is Associated With Resistance to Effects of Leptin on Fat Distribution and Insulin Action

Leptin has been shown to modulate total body fat and visceral fat distribution and to enhance insulin action in young rats. We hypothesize that failure of leptin action may contribute to the increase in visceral fat and insulin resistance in aging. By chronic subcutaneous infusion of leptin over 7 days, we increased leptin levels in young rats to match the levels in aging ad libitum fed rats. Leptin induced an approximately 50% decrease in food intake compared with saline controls, an approximately 50% decrease in visceral fat, and improved hepatic (fourfold) and peripheral (30%) insulin action (euglycemic hyperinsulinemic clamp technique) compared with the pair-fed group (p <.001). Although the plasma leptin level was doubled in aging rats, leptin failed to produce a significant change in food intake, in fat mass and its distribution, and in hepatic and peripheral insulin action. Increasing plasma leptin levels failed to suppress leptin gene expression in aging rats as compared with the approximately 50% suppression seen in young rats (p <.01). We propose that leptin resistance may play a causative role in the metabolic decline seen with aging.

Gastro-oesophageal Reflux in Obese Subjects: Influence of Overweight, Weight Loss and Chronic Gastric Balloon Distension

Background: Gastro-oesophageal reflux is an obesity-related health risk assumed to improve after weight loss. Prolonged intragastric balloon distension might oppose this. The purpose of the study was to investigate the prevalence of gastro-oesophageal reflux in untreated obese subjects and to study the consequences of weight loss with or without intragastric balloon treatment. Methods: Patients participating in a randomized double-blind, sham-controlled trial received balloon or sham treatment for the first 13 weeks. Thereafter, all subjects received a balloon for the remaining year. Twenty-four-hour pH recordings were made at the start, after 13 weeks of balloon or sham treatment, after 26 and 52 weeks of balloon treatment and 13 weeks after balloon removal. Results: Group-wise, pH data of 42 untreated patients (BMI 43.4 kg/m 2 ) were highly abnormal. On an individual level, 22 subjects (52%) had some evidence of reflux, 17 patients (40%) showed pathological total reflux times and 8 (19%) had combined total, upright and supine reflux with grade B reflux oesophagitis in only one patient. Albeit poorly, oesophageal acid exposure was related to body weight and visceral fat distribution. A reduction in acid reflux was observed in sham-treated weight-losing subjects, whereas in balloon-treated subjects supine reflux and duration of the longest reflux increased. In the second 13-week period, the initially improved pH values worsened by balloon placement in sham-treated subjects. Values in balloon-balloon-treated subjects stabilized. After 52 weeks, acid reflux levelled off at pretreatment values and further improved after balloon removal. At these times, decreased visceral fat masses correlated significantly with diminished oesophageal exposure to acid. Conclusions: Obesity predisposed to gastro-oesophageal reflux. Body weight loss and, strikingly, visceral fat loss resulted in improved reflux parameters. Adverse effects on acid reflux by gastric balloon distension wore off over time.

Increased visceral fat distribution in drug-naive and drug-free patients with schizophrenia

To investigate visceral fat distribution in patients with schizophrenia. Cross sectional study using CT scanning in patients with drug-naive and drug-free schizophrenia. Fifteen (13 men and two women) subjects with schizophrenia (mean age 33.7 y; mean body mass index (BMI)=26.7 kg/m(2)), and 15 age- and sex-matched controls (mean age 30.5 y; mean BMI=22.8 kg/(2)). Various fatness and fat distribution parameters (by CT scanning and anthropometry) and 16:00 h plasma cortisol. In comparison to controls, patients with schizophrenia had central obesity and had significantly higher levels of plasma cortisol. Furthermore, previous neuroleptic exposure did not appear to influence these findings as both drug-naive and drug-free patients had equally high levels of visceral fat deposition. Central obesity is a well recognized risk factor in developing certain general medical conditions. This study shows that patients with schizophrenia have increased intra-abdominal fat which may provide one explanation for why they die prematurely.