Obesity is characterized by abnormal and excessive adipose tissue accumulated in the body. Compared with peripheral obesity (the accumulation of subcutaneous adipose tissue), abdominal obesity (the accumulation of visceral adipose tissue) is associated with increased risk of the metabolic syndrome, such as diabetes, hypertension, atherosclerosis, and dyslipidemia. Adipose tissue is a highly heterogeneous endocrine organ. Adipose tissue depots differ significantly in anatomy, cell biology, glucose and lipid metabolism as well as in endocrine regulation. Visceral adipose tissue has a stronger metabolic activity and secrets a larger amount of free fat acids, adipocytokines, hormones and inflammatory factors, which flux into the liver directly via the hepatic portal vein. These characteristics indicate that visceral adiposity may lead to the metabolic syndrome and thus visceral adipose tissue might be the clinical target for the prevention and treatment of obesity.
Adipose Tissue ; pathology ; Humans ; Intra-Abdominal Fat ; pathology ; Lipid Metabolism ; Metabolic Syndrome ; physiopathology ; Obesity ; physiopathology ; Obesity, Abdominal ; physiopathology ; Subcutaneous Fat ; pathology

OBJECTIVETo investigate the relationship between adiponectin and beta-cell function in abdominal visceral obesity women.

METHODSNine abdominal visceral obesity women (VO), 9 normal subjects (C) and 7 patients with type 2 diabetes mellitus (T2DM) were enrolled in the study. Beta-cell function and insulin sensitivity were determined by hyperglycemic clamp, fasting serum adiponectin was assayed by ELISA and regional body fat was measured by MRI.

RESULTThe levels of first phase insulin release (FPIR), glucose disposal rates (GDR), insulin sensitivity index (ISI) and adiponectin were significantly elevated in control group compared with VO group and T2DM group. As compared with T2DM group, the levels of adiponectin, FPIR, second phase insulin release (SPIR) and maximum insulin release (INS(max)) increased significantly in VO group. Multiple stepwise regression analysis showed that age, FPIR and GDR were positively correlated to adiponectin (B=0.145, 0.194, 0.277 respectively, all P<0.05), while waist-hip ratio was negatively correlated with adiponectin (B=-7.424, P<0.05).

CONCLUSIONThe visceral obesity women have lower adiponectin levels, and hyperadiponectinemia may be the link with insulin secretion.

Abdominal Fat ; Adiponectin ; blood ; Adult ; Female ; Glucose Clamp Technique ; Humans ; Insulin-Secreting Cells ; physiology ; Middle Aged ; Obesity ; blood ; physiopathology

OBJECTIVECentral obesity is considered to be a central component of metabolic syndrome. Waist circumference (WC) has been widely used as a simple indicator of central obesity. This study is aimed to evaluate the sensitivity of WC cut-off values for predicting metabolic risk factors in middle-aged Chinese.

METHODSThe study involved 923 subjects aged 40-65 years. The metabolic risk factors were defined according to the Chinese Joint Committee for Developing Chinese Guidelines on Prevention and Treatment of Dyslipidemia in Adults. WC cut-off 85-90 cm and ⋝90 cm were used as cut-off values of central pre-obesity and central obesity in males, respectively, while WC 80-85 cm and ⋝85 cm were used as cut-off values of central pre-obesity and central obesity in females.

RESULTSFirst, WC values corresponding to body mass index (BMI) 24 kg/m2 and visceral fat area (VFA) 80 cm2 were 88.55 cm and 88.51 cm in males, and 81.46 cm and 82.51 cm in females respectively. Second, receiver operating characteristic curves showed that the optimal WC cut-off of value was 88.75 cm in males, higher than that in females (81.75 cm). Third, the subjects with higher WC values were more likely to have accumulating metabolic risk factors. The prevalence of metabolic risk factors increased linearly and significantly in relation to WC levels.

CONCLUSIONWC cut-off values of central pre-/central obesity are optimal to predict multiple metabolic risk factors.

Aged ; China ; epidemiology ; Cross-Sectional Studies ; Female ; Humans ; Intra-Abdominal Fat ; physiopathology ; Male ; Metabolic Syndrome ; diagnosis ; epidemiology ; physiopathology ; Middle Aged ; Obesity ; diagnosis ; ROC Curve ; Waist Circumference

PURPOSE: This study sought to determine whether abdominal obesity is a risk factor for impaired fasting glucose (IFG) and hypertriglyceridemia and to verify whether moderate effect of abdominal obesity on the relationship between IFG and hypertriglyceridemia in Korea. MATERIALS AND METHODS: Data from the Korean National Health and Nutrition Examination Survey was used for the analysis. The study population included 5,938 subjects aged 20 year old drawn from non-diabetic participants in a health examination survey. The subjects were classified according to the presence of abdominal obesity based on waist circumference, IFG based on their fasting blood glucose level, and hypertriglyceridemia on their fasting triglyceride. RESULTS: The multivariate-adjusted odds ratios for the occurrence of hypertriglyceridemia were 2.91 in the abdominal obesity group as compared with the nonobesity group and 1.31 in subjects with IFG compared with the normoglycemia controls. Abdominal obesity was found to be positively moderated in the interaction between waist circumference and fasting blood sugar. CONCLUSION: The moderate effect between abdominal obesity and IFG contributes to the development of hypertriglyceridemia in Korea.
Adult ; Aged ; Blood Glucose/*metabolism ; Fasting/blood ; Female ; Humans ; Hypertriglyceridemia/*blood/*pathology ; Logistic Models ; Male ; Middle Aged ; Obesity, Abdominal/*physiopathology ; Triglycerides/blood ; Waist Circumference/physiology ; Young Adult

BACKGROUND/AIMS: Obstructive sleep apnea (OSA) is associated with an increased risk of obesity and non-alcoholic fatty liver disease (NAFLD), but it remains unclear whether the risk of NAFLD is independently related to OSA regardless of visceral obesity. Thus, the aim of the present study was to examine whether OSA alone or in combination with excessive daytime sleepiness (EDS) or short sleep duration was associated with NAFLD independent of visceral fat in Korean adults. METHODS: A total of 621 participants were selected from the Korean Genome and Epidemiology Study (KoGES). The abdominal visceral fat area (VFA) and hepatic fat components of the participants were assessed using computed tomography scans and they were then categorized into four groups depending on the presence of OSA and EDS. RESULTS: The proportions of NAFLD were 21.1%, 18.5%, 32.4%, and 46.7% in participants without OSA/EDS, with only EDS, with only OSA, and with both OSA and EDS, respectively. A combination of OSA and EDS increased the odds ratio (OR) for developing NAFLD (OR, 2.75; 95% confidence interval [CI], 1.21 to 6.28) compared to those without OSA/EDS, and this association remained significant (OR, 2.38; 95% CI, 1.01 to 5.59) even after adjusting for VFA. In short sleepers (< 5 hours) with OSA, the adjusted OR for NAFLD was 2.50 (95% CI, 1.08 to 5.75) compared to those sleeping longer than 5 hours without OSA. CONCLUSIONS: In the present study, OSA was closely associated with NAFLD in Korean adults. This association was particularly strong in those with EDS or short sleep duration regardless of VFA.
*Adiposity ; Aged ; Asian Continental Ancestry Group ; Chi-Square Distribution ; Disorders of Excessive Somnolence/diagnosis/*epidemiology/physiopathology ; Female ; Humans ; Intra-Abdominal Fat/*physiopathology ; Logistic Models ; Male ; Middle Aged ; Multivariate Analysis ; Non-alcoholic Fatty Liver Disease/diagnosis/*epidemiology/physiopathology ; Obesity, Abdominal/diagnosis/*epidemiology/physiopathology ; Odds Ratio ; Republic of Korea/epidemiology ; Risk Factors ; *Sleep ; Sleep Apnea, Obstructive/diagnosis/*epidemiology/physiopathology

OBJECTIVETo study the changes of insulin sensitivity in individuals with impaired glucose tolerance and diabetes and the relationship between insulin sensitivity and over weight/obesity (OW/OB) .

METHODSFifty-two individuals were divided into 4 groups according to WHO diagnostic criteria of obesity (1998) and diabetes (1999): normal weight with normal glucose tolerance (NW-NGT) group, OW/OB with normal glucose tolerance (OW/OB-NGT) group, OW/OB with impaired glucose tolerance (OW/OBIGT) group and OW/OB with diabetes mellitus (OW/OB-DM) group. Individuals in OW/OB-NGT group were further classified into 3 subgroups: over weight subgroup, mild obesity subgroup, and mediate obesity subgroup. Abdominal fat area was measured with magnetic resonance imaging. Visceral obesity was defined as intra-abdominal fat area over 100 cm(2). All subjects with NGT were divided into visceral obesity (VA) group and non-visceral obesity ( Non-VA) group. Extended hyperinsulinemic euglycemic clamp was performed to assess the peripheral tissue insulin sensitivity in all subjects.

RESULTSThe rates of insulin mediated glucose disappearance (Rd) were (3. 25+/-0. 13) mg x kg (-1) min (-1) in OW/OB-NGT group, (3. 06+/-0. 26) mg x kg(-1) x min(-1) in OW/OB-IGT group, and (3.19+/-0.44) mg x kg(-1) x min (-1) in OW/OB-DM group, which were significantly lower than that in NW-NGT group [ (5. 86+/-0. 65) mg x kg (-1) min (-1) ] (P < 0. 05, P < 0.01). The Rd in over weight subgroup [(3.50+/-0. 19) mg kg(-1) x min(-1) ] , mild obesity subgroup [(3. 03+/-0. 13) mg x kg (-1) min(-1)] , and mediate obesity subgroup [(2. 75 +/-0. 24) mg x kg (-1) min(-1)] were significantly lower than that of NW-NGT group (P <0. 05, P <0. 01). The Rd [ (2. 97+/-0. 12) mg kg(-1) x min(-1) vs (4.55+/-0.43) mg x kg(-1) x min(-1)] and glucose oxidation [(1.47 +/-0. 19) mg x kg(-1) min(-1) vs (2.24 +/-0. 19) mg kg(-1) x min(-1) in VA group were significantly decreased than that in non-VA group (P < 0. 05, P < 0. 01). Body mass index, waist and hip ratio, waist circumference, and intra-abdominal fat area were negatively correlated with Rd, respectively (P < 0. 01). Multiple regression analysis showed that body mass index, intra-abdominal fat area and abdominal subcutaneous fat area were the main risk factors of insulin sensitivity.

CONCLUSIONSInsulin sensitivity decreased in OW/OB individuals with or without hyperglycemia. Insulin sensitivity is lower in subjects with visceral obesity. Total body fat and abdominal fat are the main risk factors of insulin sensitivity.

Adolescent ; Adult ; Body Mass Index ; Female ; Glucose Clamp Technique ; methods ; Glucose Intolerance ; etiology ; Humans ; Insulin Resistance ; Intra-Abdominal Fat ; metabolism ; Male ; Middle Aged ; Obesity ; complications ; physiopathology ; Subcutaneous Fat, Abdominal ; metabolism

OBJECTIVETo observe the relationship between abdominal obesity and left ventricular weight/function.

METHODSA total of 495 patients [265 males, mean age (55 +/- 12) years] with hypertension (139), diabetes (65), metabolic syndrome (285), diabetes complicated with hypertension (11) were enrolled in this study. Visceral adipose area (VA), the subcutaneous adipose (SA), the total abdominal adipose (TA) were measured by computerized tomography (CT) and left ventricular weight and function were obtained by echocardiography. Patients were divided into three groups according to the VA (I. VA<75 cm(2), n=173, II. VA>75 and < 110 cm(2), n=153, III. VA >or= 110 cm(2), n=169).

RESULTSLeft ventricular mass (LVM) and LVM index (LVMI) increased and LVEF and E/A decreased in proportion to increasing VA. Left ventricular hypertrophy (LVH) rate was significantly higher in group II and III compared to group I and LVEF was significantly reduced in group III compared to group I and II. There are significant correlation between LVMI and VA, SA, TA as well as between LVEF and VA after adjusting gender, age and blood pressure. Logistic regression analysis showed that VA is an independent predictor for LVH.

CONCLUSIONThe abdominal adipose accumulation is closely related to the left ventricular weight and function.

Abdominal Fat ; physiology ; physiopathology ; Adult ; Aged ; Aged, 80 and over ; Diabetes Mellitus ; diagnostic imaging ; Female ; Humans ; Hypertension ; diagnostic imaging ; Inpatients ; Male ; Metabolic Syndrome ; diagnostic imaging ; Middle Aged ; Obesity ; physiopathology ; Radiography ; Ultrasonography ; Ventricular Function, Left ; Ventricular Remodeling

OBJECTIVETo determine the prevalence and clinical phenotype of metabolic syndrome among overweight and obese schoolchildren in Beijing, and to compare the rates of diagnosis made according to the criteria of the National Cholesterol Education Program (NCEP) of the United States and International Diabetes Federation (IDF).

METHODSBased on Beijing Child and Adolescent Metabolic Syndrome (BCAMS) study with body mass index (BMI), waist circumference (WC) and blood pressure measured, the overweight and obese children were screened among nearly 20 000 children 6-18 years of age in Beijing by Chinese BMI cutoffs for schoolchildren (7-18 years) and the US 2000 CDC Growth Charts--the 85th and 95th percentile (6 years) and were enrolled as the study population. Simultaneously a group of children with normal BMI were selected as the control group and based on the international method of age grouping, each of the above groups was divided further into 4 sub-groups in terms of age: 6-9, 10-12, 13-15 and 16-18 years old, respectively. Fasting plasma glucose (FPG) and insulin (FINS), serum high-density lipoprotein cholesterol (HDL-C) and triglyceride (TG) were examined. HOMA-IR index was calculated for estimating individual insulin resistance. A child who met any three or more of the following five criteria, according to NCEP definition, was diagnosed as MS. A diagnosis of MS using IDF definition required abdominal obesity plus any two or more of the other four criteria: (1) abnormal obesity: WC > or = P(90); (2) elevated BPs: SBP/DBP > or = P(90); (3) low HDL-C: HDL-C < 1.03 mmol/L (40 mg/dl); (4) high TG: TG > or = 1.24 mmol/L (110 mg/dl); (5) impaired fasting glucose (IFG): FPG > or = 5.6 mmol/L (100 mg/dl).

RESULTSThe prevalence rates of MS by NCEP definition were: 0.9%, 7.6% and 29.8% in the normal weight (control group), overweight and obese children, respectively, which were higher than the rates diagnosed by IDF definition with 0.1%, 5.2% and 28.6% in the three groups. The prevalence rates of individual MS component among obese children were: 81.6% for abnormal obesity, 47.7% for elevated BPs, 35.6% for high TG, 16.9% for low HDL-C, and 13.4% for IFG. Elevated BPs (29.8%), abnormal obesity (27.4%) and high TG (26.0%) were the leading three abnormalities among overweight children. With the increase of BMI, the clustering of MS components and insulin resistance (HOMA-IR) were remarkably increased. HOMA-IR significantly increased as the number of MS component increased.

CONCLUSIONSMS has been in an epidemic status among the obese schoolchildren in Beijing. Abnormal obesity, elevated BPs and high TG were the three most common metabolic abnormalities for overweight and obese children. The prevalence rates of MS by NCEP definition in the present study was higher than those diagnosed by using IDF definition.

Adolescent ; Blood Glucose ; analysis ; Body Mass Index ; Body Weight ; Child ; China ; epidemiology ; Cholesterol ; blood ; Cholesterol, HDL ; blood ; Cholesterol, LDL ; blood ; Diabetes Mellitus, Type 2 ; metabolism ; Growth Charts ; Humans ; Insulin ; analysis ; Insulin Resistance ; genetics ; physiology ; Male ; Metabolic Syndrome ; physiopathology ; Obesity ; epidemiology ; metabolism ; physiopathology ; Obesity, Abdominal ; pathology ; Overweight ; epidemiology ; etiology ; metabolism ; Prevalence ; Triglycerides ; analysis ; Waist Circumference

PURPOSE: We examined the relationship between portal venous velocity and hepatic-abdominal fat in patients with nonalcoholic fatty liver disease (NAFLD), using spectral Doppler ultrasonography (US) and magnetic resonance imaging (MRI). MATERIALS AND METHODS: In this prospective study, 35 patients with NAFLD and 29 normal healthy adults (control group) underwent portal Doppler US. The severity of hepatic steatosis in patients with NAFLD was assessed by MRI through chemical shift imaging, using a modification of the Dixon method. Abdominal (intra-abdominal and subcutaneous) fat was measured by MRI. RESULTS: The difference in portal venous velocity between the patients with NAFLD and the control group was significant (p < 0.0001). There was no correlation between the degree of abdominal or hepatic fat and portal venous velocity (p > 0.05). There were strong correlations between the hepatic fat fraction and subcutaneous adiposity (p < 0.0001), intraperitoneal fat accumulation (p = 0.017), and retroperitoneal fat accumulation (p < 0.0001). CONCLUSION: Our findings suggest that patients with NAFLD have lower portal venous velocities than normal healthy subjects.
Abdominal Fat/pathology ; Adult ; Aged ; Blood Flow Velocity/*physiology ; Case-Control Studies ; Fatty Liver/*physiopathology/*ultrasonography ; Female ; Humans ; Image Interpretation, Computer-Assisted ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Obesity/complications ; Overweight/complications ; Portal Vein/*ultrasonography ; Prospective Studies ; *Ultrasonography, Doppler

BACKGROUND/AIMS: The objective of this study was to determine whether insulin resistance is associated with gallbladder stone formation in Korean women based on menopausal status. METHODS: The study included 4,125 consecutive Korean subjects (30-79 years of age). Subjects who had a medical history of diabetes, hypertension, dyslipidemia, other cardiovascular disorders, or hormone replacement therapy were excluded. The women were subdivided into two groups according to their menopausal status. RESULTS: Analysis of premenopausal women showed no significant differences in the homeostasis model of assessment-insulin resistance (HOMA-IR) index between the two groups in terms of gallstone disease. The associations between the occurrence of gallbladder stones and age, obesity, abdominal obesity, hyperinsulinemia, and high HOMA-IR index were statistically significant in the analysis with postmenopausal women. In a multiple logistic regression analysis, low high density lipoprotein-cholesterol was an independent predictor of gallbladder stone formation in premenopausal women. However, the multiple logistic regression analysis also showed that age and HOMA-IR were significantly associated with gallbladder stone formation in postmenopausal women. In an additional analysis stratified by obesity, insulin resistance was a significant risk factor for gallbladder stone formation only in the abdominally obese premenopausal group. CONCLUSIONS: Insulin resistance may be associated with gallbladder stone formation in Korean postmenopausal women with abdominal obesity.
Adult ; Age Factors ; Aged ; Asian Continental Ancestry Group/*statistics & numerical data ; Chi-Square Distribution ; Female ; Gallstones/*ethnology/physiopathology/ultrasonography ; Humans ; Insulin Resistance/*ethnology ; Logistic Models ; Middle Aged ; Obesity, Abdominal/ethnology ; Odds Ratio ; Postmenopause/*ethnology ; Questionnaires ; Republic of Korea/epidemiology ; Risk Assessment ; Risk Factors