Contribution of visceral fat accumulation to the development of coronary artery disease in non-obese men

Metabolic syndrome--a new world-wide definition. A Consensus Statement from the International Diabetes Federation

AIMS

To establish a unified working diagnostic tool for the metabolic syndrome (MetS) that is convenient to use in clinical practice and that can be used world-wide so that data from different countries can be compared. An additional aim was to highlight areas where more research into the MetS is needed.

PARTICIPANTS

The International Diabetes Federation (IDF) convened a workshop held 12-14 May 2004 in London, UK. The 21 participants included experts in the fields of diabetes, public health, epidemiology, lipidology, genetics, metabolism, nutrition and cardiology. There were participants from each of the five continents as well as from the World Health Organization (WHO) and the National Cholesterol Education Program-Third Adult Treatment Panel (ATP III). The workshop was sponsored by an educational grant from AstraZeneca Pharmaceuticals.

CONSENSUS PROCESS

The consensus statement emerged following detailed discussions at the IDF workshop. After the workshop, a writing group produced a consensus statement which was reviewed and approved by all participants.

CONCLUSIONS

The IDF has produced a new set of criteria for use both epidemiologically and in clinical practice world-wide with the aim of identifying people with the MetS to clarify the nature of the syndrome and to focus therapeutic strategies to reduce the long-term risk of cardiovascular disease. Guidance is included on how to compensate for differences in waist circumference and in regional adipose tissue distribution between different populations. The IDF has also produced recommendations for additional criteria that should be included when studying the MetS for research purposes. Finally, the IDF has identified areas where more studies are currently needed; these include research into the aetiology of the syndrome.

The metabolic syndrome and adipocytokines

Visceral fat accumulation has been shown to play crucial roles in the development of cardiovascular disease as well as the development of obesity-related disorders such as diabetes mellitus, hyperlipidemia and hypertension and the so-called metabolic syndrome. Given these clinical findings, adipocytes functions have been intensively investigated in the past 10 years, and have been revealed to act as endocrine cells that have been termed adipocytokines, which secrete various bioactive substances. Among adipocytokines, tumor necrosis factor-alpha, plasminogen activator inhibitor type 1 and heparin binding epidermal growth factor-like growth factor are produced in adipocytes as well as other organs, and may contribute to the development of vascular diseases. Visfatin has been identified as a visceral-fat-specific protein that might be involved in the development of obesity-related diseases, such as diabetes mellitus and cardiovascular disease. On the contrary to these adipocytokines, adiponectin, an adipose-tissue-specific, collagen-like protein, has been noted as an important antiatherogenic and antidiabetic protein, or as an anti-inflammatory protein. The functions of adipocytokine secretion might be regulated dynamically by nutritional state. Visceral fat accumulation causes dysregulation of adipocyte functions, including oversecretion of tumor necrosis factor-alpha, plasminogen activator inhibitor type 1 and heparin binding epidermal growth factor-like growth and hyposecretion of adiponectin, which results in the development of a variety of metabolic and circulatory diseases. In this review, the importance of adipocytokines, especially focusing on adiponectin is discussed with respect to cardiovascular diseases.

Therapy Insight: adipocytokines in metabolic syndrome and related cardiovascular disease

Abdominal fat accumulation has been shown to play crucial roles in the development of metabolic syndrome. Visceral fat accumulation particularly is closely correlated to the development of cardiovascular disease and obesity-related disorders such as diabetes mellitus, hyperlipidemia and hypertension. Given these clinical findings, the functions of adipocytes have been intensively investigated in the past 10 years, and have been revealed to act as endocrine cells that secrete various bioactive substances termed adipocytokines. Among adipocytokines, tumor-necrosis factor-alpha, plasminogen activator inhibitor type 1 and heparin-binding epidermal growth factor-like growth factor are produced in adipocytes as well as other organs, and contribute to the development of vascular diseases. Visfatin has been identified as a visceral-fat-specific protein that might be involved in the development of obesity-related diseases, such as diabetes mellitus and cardiovascular disease. In contrast to these adipocytokines, adiponectin, which is an adipose-tissue-specific, collagen-like protein, has been noted as an important antiatherogenic and antidiabetic protein, or as an anti-inflammatory protein. The functions of adipocytokine secretion might be regulated dynamically by nutritional state. Visceral fat accumulation causes dysregulation of adipocyte functions, including oversecretion of tumor-necrosis factor-alpha, plasminogen activator inhibitor type 1 and heparin-binding epidermal growth factor-like growth factor, and hyposecretion of adiponectin, which results in the development of a variety of metabolic and circulatory diseases. In this review, the importance of adipocytokines, particularly adiponectin, is discussed with respect to cardiovascular diseases.

Adiponectin: Identification, physiology and clinical relevance in metabolic and vascular disease

Adiponectin is the most abundant adipose-specific protein. Its expression is reduced in obesity, insulin resistance and type 2 diabetes, and plasma concentrations are inversely related to body weight, especially visceral adiposity. Adiponectin is also inversely associated with other traditional cardiovascular risk factors, such as blood pressure, low-density lipoprotein cholesterol and triglyceride levels, and is positively related to high-density lipoprotein cholesterol (HDL-C) levels. Recent research has indicated that adiponectin has anti-inflammatory, anti-atherogenic and antidiabetic properties. The ability of adiponectin to reduce insulin resistance in conjunction with its anti-inflammatory and anti-atherogenic properties makes this novel adipocytokine a promising therapeutic target, and agents that enhance adiponectin secretion or action have potential for treatment of metabolic and vascular disease. Current management strategies that may increase endogenous adiponectin production in humans include weight loss, soy protein and therapy with peroxisome proliferator-activating receptor gamma (PPARgamma) agonists.

Aquaporins and glycerol metabolism

The discovery of aquaporin (AQP) has made a great impact on life sciences. AQPs are a family of homologous water channels widely distributed in plants, unicellular organisms, invertebrates, and vertebrates. So far, 13 AQPs have been identified in human. AQP3, 7, 9, and 10 are subcategorized as aquaglyceroporins which permeabilize glycerol as well as water. Many investigators have demonstrated that AQPs play a crucial role in maintaining water homeostasis, but the physiological significance of some AQPs as a glycerol channel is not fully understood. Adipose tissue is a major source of glycerol and glycerol is one of substrates for gluconeogenesis. This review focuses on recent studies of glycerol metabolism through aquaglyceroporins, and briefly discusses the importance of glycerol channel in adipose tissues and liver.

Cutoff and Target Values for Intra-Abdominal Fat Area for Prevention of Metabolic Disorders in Pre- and Post-Menopausal Obese Women Before and After Weight Reduction

BACKGROUND

The Japan Society for the Study of Obesity originally proposed a cutoff value of >100 cm(2) for the intra-abdominal fat area (IFA) as a definition for "visceral fat obesity" in Japanese adults. There are no studies on the cutoff or target values after weight reduction in pre- and post-menopausal women.

METHODS AND RESULTS

In the present study 149 pre-menopausal obese women (PreM, 43.3 years, 27.3 kg/m(2)) and 58 post-menopausal women (PostM, 53.9 years, 27.7 kg/m(2)) participated in a 14-week weight reduction program. The IFA was measured by computed tomography. The program induced significant reductions in body weight (8.6 kg in PreM and 7.8 kg in PostM). The IFA decreased significantly from 80.4 +/- 41.3 to 50.7 +/- 23.8 (PreM) and from 115.4 +/- 38.0 to 75.7 +/- 30.5 (PostM).

CONCLUSIONS

The receiver-operating characteristic curve analyses revealed that the appropriate cutoff values were 80 cm(2) (PreM) and 110 cm(2) (PostM) before the program, and after the program the appropriate target values were determined as 60 and 70 cm(2), respectively.

The effect of moxonidine on endothelial dysfunction in metabolic syndrome

BACKGROUND

Endothelial dysfunction has been reported in patients with type 2 diabetes mellitus and even in healthy obese individuals with a normal metabolic profile. Sympathetic activity commonly is increased in obese hypertensive patients, and moxonidine is effective in lowering BP and improving insulin sensitivity.

OBJECTIVE

To evaluate the effect of moxonidine on endothelial dysfunction in patients with metabolic syndrome.

METHODS

Twenty-six patients with mild hypertension were treated with moxonidine and a hypocaloric diet for 3 months, while a second normotensive group (n = 26) were followed-up with calorie restriction alone. Anthropometric (body mass index, waist and hip circumferences, and waist-to-hip ratio) and metabolic features (fasting plasma glucose and insulin, aminotransferases, gamma-glutamyl transpeptidase, triglycerides, and cholesterol levels) and flow-mediated dilatation (FMD) were evaluated. Insulin resistance was calculated by using the homeostasis model assessment formula. Insulin sensitivity was calculated according to the quantitative insulin-sensitivity check index (QUICKI).

RESULTS

SBP and DBP (both p < 0.001) and waist circumference (p = 0.02) were higher, and QUICKI (p = 0.043) and FMD (p = 0.01) were lower in the hypertensive group at baseline. After 3 months, nearly all the study parameters improved in both treatment groups. The decrease in BP, increase in FMD, and improvements in metabolic and anthropometric parameters were significantly greater in the moxonidine-treated group than in those treated with diet alone.

CONCLUSION

Moxonidine is proposed as a valuable option for treating mild-to-moderate hypertension in obese and insulin-resistant patients with metabolic syndrome as it appears to improve endothelial dysfunction in these patients.

Gender Differences in the Association between Anthropometric Indices of Obesity and Blood Pressure in Japanese

To investigate which of four anthropometric variables of obesity has the strongest association with blood pressure (BP), and to investigate whether there are gender differences in these relationships in Asian adults, we evaluated the associations of four anthropometric variables, body mass index (BMI), waist circumference, waist-to-hip ratio and waist-to-height ratio, with BP and the prevalence of hypertension in a cross-sectional study. A total of 4,557 employees of a metal-products factory in Toyama, Japan (2,935 men and 1,622 women, aged 35 to 59 years) were included in the study. Waist circumference in men and BMI in women had the strongest associations with BP. As for the age-adjusted rate ratio (RR) of the prevalence of hypertension for one standard deviation increase in each anthropometric variable, RR was the highest for waist circumference in men (RR, 1.44; 95% confidence interval [CI], 1.31-1.58), and for BMI in women (RR, 1.61; 95% CI, 1.38-1.88). The associations of waist circumference in men and BMI in women remained significant after adjustment for each of the other variables. The associations of waist-to-height ratio with BP and the prevalence of hypertension were a little weaker than those of waist circumference for both men and women. In conclusion, among four anthropometric variables of obesity--i.e., BMI, waist circumference, waist-to-hip ratio, and waist-to-height ratio-waist circumference had the strongest association with BP and the prevalence of hypertension in men and BMI had the strongest association with BP and hypertension in women. Waist circumference in men and BMI in women should be given more importance in the screening of and guidelines on hypertension in Asians.

Association between Plasma Adiponectin Concentration and Visceral Fat Accumulation in Hemodialysis Patients

BACKGROUND

Cardiovascular diseases resulting from atherosclerotic complications are major causes of death in hemodialysis (HD) patients. Adiponectin (ADPN) is a recently discovered adipocyte-derived protein that appears to have protective role against atherosclerosis. HD patients have an excess accumulation of intra-abdominal fat mass in association with an atherogenic serum lipid profile despite low body mass index; however, the role of intra-abdominal fat mass in the progress of atherosclerosis remains to be clarified.

METHODS

We evaluated visceral (VFA) and subcutaneous fat areas (SFA) by computed tomography and measured the plasma ADPN in 47 HD patients. We also examined the relationship between visceral fat accumulation and plasma ADPN levels and clinical parameters related to atherosclerosis.

RESULTS

Plasma ADPN was 29.0 +/- 12.5 microg/ml in HD patients (mean +/- SD), two-fold higher than that in control subjects (14.0 +/- 9.1 microg/ml). Plasma ADPN correlated significantly and negatively with visceral fat area (VFA) (r = -0.49, p < 0.001) and subcutaneous fat area (SFA) (r = -0.42, p < 0.01) in HD patients. Plasma ADPN also correlated significantly and positively with HDL-cholesterol (r = 0.45, p < 0.005) and significantly and negatively with atherosclerotic index (AI, r = -0.39, p < 0.01) and triglycerides (r = -0.32, p < 0.05) in HD patients. Multiple stepwise regression analysis identified VFA as a significant independent predictor of plasma ADPN concentration in HD patients.

CONCLUSION

Our findings indicate that visceral fat is a major determinant of plasma ADPN level, suggesting that visceral fat accumulation might be closely associated with the progression of atherosclerotic vascular disease in HD patients.

A technique for the measurement of visceral fat by ultrasonography: comparison of measurements by ultrasonography and computed tomography

OBJECTIVE

This study aims to create a method of calculating intra-abdominal visceral fat volume by using ultrasound (US). The visceral fat volume measured by US was evaluated by comparison with the volume measured by computed tomography (CT).

METHODS

Eighty-seven patients (52 males and 35 females) were enrolled in this study. Both US and CT were performed, and the visceral fat volume was measured. Both the distance and thickness of the parameters in US were measured as follows: 1) the distance between the internal surface of the abdominal muscle and the splenic vein, 2) the distance between the internal surface of the abdominal muscle and the posterior wall of aorta on the umbilicus, and 3) the thickness of the fat layer of the posterior right renal wall.

RESULTS

The equation was calculated as follows: [visceral fat volume]=-9.008+1.191x[distance between the internal surface of the abdominal muscle and the splenic vein (mm)]+0.987x[distance between the internal surface of the abdominal muscle and the posterior wall of the aorta on the umbilicus (mm)]+3.644x[thickness of the fat layer of the posterior right renal wall (mm)]. There was a good correlation between the visceral fat volume calculated by the above equation and the volume by CT described (r=0.860, p<0.0001).

CONCLUSION

The measurement of the visceral fat volume using US provided results as effectively as CT, and it was proven to be a useful method.

Reciprocal association between visceral obesity and adiponectin: in healthy premenopausal women

BACKGROUND

Obesity is one of the well-known risk factors of vascular disorders; however, the molecular mechanisms underlying the association between the two remain undetermined. Previous studies have demonstrated that the plasma levels of adiponectin, an adipose-derived hormone, are reduced in obese subjects, and that this hypoadiponectinemia is associated with ischemic heart disease. In this study, we sought to identify the primary determinants of plasma adiponectin levels in healthy premenopausal women.

METHODS AND RESULTS

We analyzed the plasma adiponectin concentrations in age-matched healthy obese premenopausal women [n=37, body mass index (BMI)> or= 25 kg/m(2)] and in healthy nonobese premenopausal women (n = 23, BMI < 25 kg/m(2)). Visceral and subcutaneous fat (VCF and SCF) areas were determined by abdominal computed tomography (CT) scan. Plasma levels of adiponectin in obese subjects were lower than in nonobese subjects (3.24 +/- 1.08 vs. 4.90 +/- 2.06 ug/ml, P < 0.01). Significant, univariate inverse correlations were observed between adiponectin levels and visceral fat areas (r = -0.643, p < 0.001), subcutaneous fat areas (r = -0.407, p < 0.01), and hsCRP (r = -0.36, p = 0.007). Plasma levels of adiponectin correlated positively with insulin sensitivity [quantitative insulin sensitivity check index (QUICKI): r = 0.38, p = 0.005] and high-density lipoprotein (HDL) cholesterol (r = 0.44, p = 0.001), and negatively with low-density lipoprotein (LDL) cholesterol (r = -0.29, p = 0.028), triglyceride (r = -0.33, p = 0.013), and BMI (r = -0.48, p < 0.001). By multivariate analysis, only visceral fat areas affected adiponectin plasma levels (beta = -0.016, p < 0.05, R(2) = 0.504). Plasma levels of HDL cholesterol remained significantly correlated to plasma adiponectin concentrations in multivariate analysis (beta = 0.067, p < 0.05).

CONCLUSIONS

These results collectively indicate that plasma HDL cholesterol levels and visceral fat masses are independently associated with plasma adiponectin concentrations.

High dose of Garcinia cambogia is effective in suppressing fat accumulation in developing male Zucker obese rats, but highly toxic to the testis

We investigated the ability of Garcinia cambogia extract containing (-)-hydroxycitric acid (HCA) to suppress body fat accumulation in developing male Zucker obese (fa/fa) rats. We also examined histopathologically the safety of its high doses. Diets containing different levels of HCA (0, 10, 51, 102 and 154 mmol/kg diet) were fed to 6-week-old rats for 92 or 93 days. Each diet group was pair-fed to the 154 mmol HCA/kg diet group. Epididymal fat accumulation and histopathological changes in tissues were observed. The highest dose of HCA-containing Garcinia cambogia (154 mmol HCA/kg diet) showed significant suppression of epididymal fat accumulation in developing male Zucker obese rats, compared with the other groups. However, the diets containing 102 mmol HCA/kg diet and higher (778 and 1244 mg HCA/kg BW/d, respectively) caused potent testicular atrophy and toxicity, whereas diets containing 51 mmol HCA/kg diet (389 mg HCA/kg BW/d) or less did not. Accordingly, 51 mmol HCA/kg diet (389 mg HCA/kg BW/d) was deemed to be the no observed adverse effect level (NOAEL).

Effects of leptin receptor gene 3'-untranslated region polymorphism on metabolic profiles in young Japanese men

We investigated the effects of leptin receptor gene 3'-untranslated region (3'-UTR) polymorphism on clinical and metabolic parameters in 221 young Japanese men aged 21 to 28 years. The polymerase chain reaction-restriction fragment length polymorphism method was used to identify a pentanucleotide (CTTTA) insertion in 3'-UTR of the leptin receptor gene. Body mass index, blood pressure, plasma glucose, insulin, leptin, total cholesterol, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, triglycerides, free fatty acids, uric acid, apolipoprotein A-I (apoA-I), and cholesteryl-ester transfer protein levels were measured. There was only 1 homozygote and 38 heterozygotes for the 3'-UTR insertion allele among the 221 subjects. The insertion allele frequency was 0.090. Plasma HDL-cholesterol and apoA-I levels were significantly lower (p = 0.015 and p = 0.032 by Mann-Whitney U test, respectively) in homozygous or heterozygous carriers of the insertion allele than in subjects homozygous for the normal allele. There were no differences in other parameters measured. Furthermore, when the subjects were divided into three groups according to HDL-cholesterol level, the percentage of insertion allele-positive subjects was significantly lower in the highest HDL-cholesterol group (chi(2) = 8.42, p = 0.015). These findings suggest that serum HDL-cholesterol and apoA-I levels are influenced by the leptin receptor gene 3'-UTR polymorphism in young Japanese men.

Adiponectin as a biomarker of the metabolic syndrome

BACKGROUND

The metabolic syndrome, a cluster of abdominal obesity, dyslipidemia, hypertension and hyperglycemia, is a common basis for atherosclerotic vascular diseases in industrial countries exposed to overnutrition. Adiponectin is an adipose-derived plasma protein with anti-atherogenic and insulin-sensitizing activities.

METHODS AND RESULTS

A total of 661 Japanese adults (479 men, 53+/-10 years; 182 women 56+/-10 years) were enrolled. Plasma adiponectin concentrations correlated negatively with waist circumference, visceral fat area, serum triglyceride concentration, fasting plasma glucose, fasting plasma insulin, and systolic and diastolic blood pressure in both sexes. A positive correlation was found between plasma adiponectin and high-density lipoprotein cholesterol concentrations in both sexes. The mean number of components of the metabolic syndrome increased as the plasma adiponectin concentration decreased: 2.57+/-1.34 for men and 2.00+/-1.51 for women with adiponectin concentrations <4.0 microg/ml. In all, 52.3% of men and 37.5% of women with adiponectin concentrations <4.0 microg/ml fulfilled the criteria for metabolic syndrome.

CONCLUSION

Hypoadiponectinemia is closely associated with the clinical phenotype of the metabolic syndrome and measuring the plasma concentration of adiponectin may be useful for management of the metabolic syndrome.

Pericardial and Visceral Adipose Tissues Measured Volumetrically With Computed Tomography Are Highly Associated in Type 2 Diabetic Families

RATIONALE AND OBJECTIVES

Pericardial and visceral adipose tissue volumes can provide new insight into the complex relation between obesity, adult-onset diabetes, and cardiovascular disease. We describe a new method for quantifying pericardial adipose tissue volumes with computed tomography (CT), and present its precision and relation to established measures of adiposity.

METHODS

Eighty subjects randomly selected from a family study of sibling pairs concordant for type 2 diabetes and unaffected siblings, 69 with diabetes, had 2 cardiac CT scans with electrocardiographic gating and 1 abdominal scan as part of an examination designed to measure calcified atherosclerotic plaque. Pericardial adipose tissue and visceral adipose tissue were measured using a 3-dimensional analysis technique. Body mass index, waist circumference, waist-to-hip ratio, and percent fat by dual x-ray absorptiometry were measured during the same visit.

RESULTS

Pericardial adipose tissue volumes measured independently and in a random order from the 2 sequential cardiac CT scans obtained during the same examination were highly correlated (Spearman R = 0.99; P < 0.0001). The mean +/- standard deviation (median) pericardial adipose tissue volume was 320.5 +/- 147.3 (281.7) mL. Pericardial adipose tissue was highly correlated with total abdominal visceral adipose tissue (R = 0.81; P < 0.0001).

CONCLUSION

The significant association between pericardial and visceral adipose tissue volumes in this preliminary study suggests that pericardial, like visceral adipose tissue, may be an important predictor or risk factor for cardiovascular disease and other related illnesses and warrants further evaluation.

Metabolic Syndrome and Cardiac Disease in Japanese Men: Applicability of the Concept of Metabolic Syndrome Defined by the National Cholesterol Education Program-Adult Treatment Panel III to Japanese Men-The Tanno and Sobetsu Study

Results of a 6-year follow-up study were used to determine whether the concept of and the criteria for metabolic syndrome as defined by the National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATP III) can be applied to Japanese men for prediction of the occurrence of cardiac disease. The subjects were 808 men who underwent mass health check-ups in 1993 and who were not on medication for hypertension, diabetes or hyperlipidemia. Individuals who had hypertriglyceridemia, hypo-high density lipoprotein (HDL) cholesterolemia, high blood pressure, and/or high fasting plasma glucose levels were identified on the basis of the NCEP-ATP III criteria. Not in conformity with the NCEP-ATP Ill, however, a cut-off value of 85 cm was used for waist girth as an indicator of abdominal obesity. The subjects who had 3 or more risk factors were judged as having metabolic syndrome. The proportion of subjects having metabolic syndrome was 25.3%. In the 6-year follow-up study, cardiac disease occurred in 11.7% of the subjects in the metabolic syndrome group and in 6.7% of the subjects in the non-metabolic syndrome group. Results of regression analysis using Cox's proportional hazards model showed that subjects in the metabolic syndrome group had a 2.2-times greater risk of developing cardiac disease than did subjects in the non-metabolic syndrome group. The concept of metabolic syndrome as defined in the NCEP-ATP III was therefore considered to be useful for predicting the occurrence of cardiac disease in Japanese men.

Contribution of visceral fat accumulation to the risk factors for atherosclerosis in non-obese Japanese

OBJECTIVE

To clarify the contributions of visceral fat tissue (VAT) mass deposition to the accumulation of risk factors for atherosclerosis in normal weight subjects.

SUBJECTS AND METHODS

We investigated the relationship between VAT accumulation and both risk factors and waist circumference in non-obese subjects. In the 955 normal weight Japanese subjects (782 men and 173 women), visceral fat area (VFA), subcutaneous fat area (SFA) and waist circumference were measured through computed tomography. Total cholesterol, high-density lipoprotein (HDL) cholesterol, triglyceride, uric acid, fasting blood glucose, and 2-hour postprandial glucose in the oral glucose tolerance test (OGTT) were measured to assess the risk factors for atherosclerosis.

RESULTS

In both men and women with normal body weight, VFA was correlated with total cholesterol (r=0.78 and r=0.71, respectively), HDL cholesterol (r=-0.89 and r=-0.82, respectively), triglyceride (r=0.72 and r=0.91, respectively), uric acid (r=0.71 and r=0.69, respectively), fasting blood glucose (r=0.84 and r=0.82, respectively), OGTT 2-hour postprandial glucose (r=0.75 and r=0.50, respectively), and systolic (r=0.93 and r=0.73, respectively) and diastolic (r=0.91 and r=0.73, respectively) blood pressure. The average number of risk factors was also correlated with VFA both in men (r=0.88, p=0.005) and women (r=0.91, p=0.003) with normal body weight. Based on the results of the multiple regression analyses, among VFA, SFA, body mass index (BMI) and age, VFA was considered to be the most important predictor for explaining the average number of risk factors. We also demonstrated that VFA was correlated with the waist circumference in normal weight men (r=0.74) and women (r=0.59). In normal weight subjects, the waist circumference equivalent to more than 1.0 of the average number of risk factors was 81 cm in men and 89 cm in women.

CONCLUSION

VAT accumulation itself plays a role as a risk factor for atherosclerosis irrespective of BMI, and measurement of VFA may be more important than that of BMI for predicting the presence of risk factors in normal weight subjects. Measurement of waist circumference also might be important for assessing the possibility of VAT accumulation leading to atherosclerosis.

Differences in the relationship between lipid CHD risk factors and body composition in Caucasians and Japanese

OBJECTIVES

To examine differences in the relationship between fat distribution and lipid coronary risk factors in Caucasian and Japanese population and further to determine whether the cut-points for body mass index (BMI) and waist circumference (WC) proposed by WHO and NHLBI are applicable to Japanese population as a predictor of a lipid risk factor abnormality or not.

RESEARCH METHODS AND PROCEDURES

Subjects were 895 participants of the Baltimore Longitudinal Study of Aging in the US (BLSA) and 1705 participants of the Longitudinal Study of Aging by the National Institutes for Longevity Science in Japan (NILS-LSA). Subjects were divided into four demographic groups as younger (age<65 y) men and women, and older (age> or =65 y) men and women. Blood total cholesterol, triglycerides, LDL- and HDL-cholesterol and anthropometry were measured. Regression coefficients of BMI and WC on risk factors, sensitivity and specificity of the BMI and WC cut-points for blood lipid abnormality, and mean values of blood lipids at BMI or WC cut-points were computed in both populations.

RESULTS

Height, weight, WC and BMI were significantly greater in the BLSA than those in the NILS-LSA subjects. Total cholesterol, HDL- and LDL-cholesterol were significantly greater in the NILS-LSA than in the BLSA subjects. Sensitivities of BMI and WC cut-points were much lower in the NILS-LSA than in the BLSA subjects. Specificities of BMI and WC cut-points were higher in the NILS-LSA than in the BLSA subjects. Mean values of triglycerides, total cholesterol, HDL- and LDL-cholesterol at BMI=25 were significantly greater in the NILS-LSA than in the BLSA subjects. At the WC cut-point (94 cm for men, 80 cm for women), mean values of all lipids were significantly greater in the NILS-LSA than in the BLSA subjects with the exception of triglycerides in younger women.

CONCLUSIONS

The Japanese subjects have smaller BMI and WC, worse total and LDL-cholesterol levels and better HDL-cholesterol levels compared to Caucasians. Sensitivities of BMI and WC for predicting lipid risk factor abnormality are much lower in Japanese. The cut-points for BMI and WC proposed by WHO and NHLBI may be too high for predicting an abnormality in triglycerides, total and LDL-cholesterol in Japanese. For detecting an abnormal HDL-cholesterol level, the BMI and WC cut-points may not be as beneficial for the Japanese population as for Caucasians.

Hip girth as a predictor of abdominal adiposity in postmenopausal women

OBJECTIVES

Our primary objective was to determine whether hip girth could accurately predict abdominal fat and total body fat in postmenopausal women. A secondary objective was to investigate the relation between body mass index (BMI) and hip girth in postmenopausal women.

METHODS

Body weight, height, girths, skinfolds, and whole-body dual-energy x-ray absorptiometric scans were obtained in 75 postmenopausal women ages 45 to 76 y. Total body fat, abdominal fat, and the ratio of abdominal fat to lean mass (F:L) were calculated from the dual-energy x-ray absorptiometric scans. Equations predicting total and abdominal fat were developed for 50 subjects by using stepwise multiple regression analysis. These equations were then cross-validated in the remaining 25 subjects.

RESULTS

Hip girth was a strong predictor of total fat (r = 0.86, P < 0.0001, standard error of the estimate = 4.9 kg) and abdominal fat (r = 0.92, P < 0.0001, standard error of estimate = 0.84 kg); with age added, the standard errors of the estimate were 3.8 and 0.8 kg, respectively. Hip girth correlated with BMI (r = 0.89, P < 0.0001). The "healthy" BMI cutoff value lower than 25 kg/m2 equated to a hip girth smaller than 100 cm and an abdominal F:L lower than 1.0. Waist girth (r = 0.83, P < 0.0001) and hip girth (r = 0.76, P < 0.0001) were good predictors of abdominal F:L.

CONCLUSIONS

Hip girth is a practical and useful predictor of abdominal and total adiposity in postmenopausal women. A hip girth of 100 cm or an abdominal F:L of 1.0 can be used as an equivalent cutoff value for the "healthy" BMI value of 25 kg/m2 in this group of women.

Trends in blood pressure control in hypertensive patients with diabetes mellitus in Japan

Hypertension is often accompanied by type 2 diabetes mellitus. Recently, the American Diabetes Association (ADA) published guidelines on the treatment of hypertension in adult patients with diabetes mellitus. However, the views of general physicians on how to control blood pressure (BP) in diabetic patients and the impact of the ADA guidelines in Japan are still not known. We conducted an internet survey in May 2002: Questionnaires were e-mailed to a total of 3,616 medical doctors, of whom 441 (12.2%) properly responded. About half of the respondents (48.3%) had already read the ADA guidelines. Before being given an outline of the guidelines, the respondents' average BP level for starting medication was 152/94 mmHg, and the BP goal 133/83 mmHg; after reading the outline, these values were 149/92 and 132/82 mmHg, respectively. The goal BP decreased more after reading the guidelines in doctors who had not previously read the ADA guidelines than in those who had already read. After being given an outline of the ADA guidelines, 40.3% of respondents reported that they would select, as a first-line agent, an angiotensin II receptor antagonist (ARB), 35.6% an angiotensin-converting enzyme inhibitor (ACEI), and 18.6% a calcium channel blocker (CCB); as a second-line medication, 39.7% of the respondents would select a CCB. Seventy percent of doctors reported having at least one patient receiving CCB monotherapy; after reading the guidelines, 41.5% of these doctors said they would continue CCB monotherapy, 36.6% said they would add an ACEI or ARB, and 29.7% planned to change to an ACEI or ARB. In conclusion, our data suggest the impact of the ADA guidelines on the target BP and the first choice of antihypertensive medication in diabetic patients. ARBs and ACEIs became first-line medications, and CCBs became second-line medications to achieve the BP goal and prevent organ damage.

Adiponectin down-regulates acyl-coenzyme A:cholesterol acyltransferase-1 in cultured human monocyte-derived macrophages

Acyl-coenzyme A:cholesterol acyltransferase-1 (ACAT-1) catalyzes the formation of cholesteryl esters (CE) and plays a significant role in formation of macrophage-derived foam cells in atherosclerotic lesions. Adiponectin was reported to play an anti-atherogenic role by inhibiting class A scavenger receptor (SR-A) expression in human macrophages. To further clarify its additional property, we examined its effect on ACAT-1 expression using human macrophages. Immunoblot analyses revealed a significant reduction of ACAT-1 protein by a low concentration (1 microg/ml) of adiponectin. The ACAT activity was also decreased in parallel by adiponectin. Northern blot analyses revealed that all four ACAT-1 mRNA transcripts (2.8, 3.6, 4.3, and 7.0 kb) were decreased almost equally by adiponectin. Furthermore, acetyl-LDL-induced CE-accumulation in these macrophages was reduced significantly by this adipocytokine. These results demonstrate the inhibitory effect of adiponectin on ACAT-1 expression, suggesting that adiponectin may play an anti-atherogenic role by down-regulating the expression of ACAT-1 as well as SR-A in human macrophages.

Obesity as the core of the metabolic syndrome and the management of coronary heart disease

The global burden of coronary heart disease (CHD) has led to the introduction of international guidelines to minimize the morbidity and mortality that result from this condition. These guidelines recognize the contribution of multiple risk factors to the development of CHD and advocate a multifaceted approach to treatment. Obesity, particularly visceral adiposity, contributes to the clustering of many other risk factors, such as hypertension, insulin resistance/type 2 diabetes and dyslipidemia, within individual patients. The molecular mechanisms underlying the metabolic abnormalities induced by visceral adiposity have yet to be fully elucidated; however, adipocytokines such as adiponectin, tumor necrosis factor-alpha and resistin seem to play an important role in this process. Obesity is a major modifiable CHD risk factor, and the benefits of weight loss are numerous, leading to improvements in several co-morbidities. Guidelines advocate lifestyle changes to correct excess bodyweight and improve the CHD risk factor profile. In addition, pharmacologic therapy is recommended for the management of other risk factors, such as hypertension and dyslipidemia, which may not be adequately controlled by lifestyle changes alone. Lowering low-density lipoprotein cholesterol (LDL-C) levels is the primary target for drug therapy for CHD prevention, and statins are first-line lipid-modifying therapy. The introduction of more efficacious statins with favorable effects on the lipid profile will optimize the control of dyslipidemia. Combining these new treatments with lifestyle changes and drug therapies for managing other CHD risk factors, as part of a multifaceted approach to treatment, will have benefits for CHD prevention.

Pre-heparin Lipoprotein Lipase Mass

Lipoprotein lipase (LPL) is a lipolytic enzyme involved in catalyzing the hydrolysis of triglycerides (TG) in chylomicrons and very low-density lipoprotein (VLDL) particles. Over the last decade, the clinical significance of measuring LPL mass without heparin injection has been increasingly studied. In earlier studies, it was shown that this marker was utilized to classify type 1 hyperlipoproteinemia, which is an extremely rare metabolic disorder. Later, researchers paid more attention to the clinical significance of measuring this parameter in more common metabolic disorders. Studies have shown that pre-heparin plasma LPL mass has significant relationships with serum lipid and lipoproteins, visceral fat area, and even a marker for acute inflammation, although this might be a metabolic surrogate marker which does not appear to be involved in catalyzing the hydrolysis of TG in TG-rich lipoproteins. We suggest that pre-heparin LPL mass in plasma or sera provides us with useful and important information on the pathophysiology of metabolic disorders or acute inflammation despite its simplicity from a practical point of view.

Sex differences in the relationships of abdominal fat to cardiovascular disease risk among normal-weight white subjects

The objectives of this study are to investigate the relationships between abdominal fat and risk factors for cardiovascular disease (CVD) among normal-weight (NW) white subjects and to determine how these relationships differ by sex. NW adults (177 males and 258 females) and overweight adults (133 males and 111 females) from the Québec Family Study and the HERITAGE Family Study were retained for this study. Risk factors included systolic and diastolic blood pressures, low-density lipoprotein and high-density lipoprotein cholesterols, triglycerides, and fasting glucose. Only in NW female adults, abdominal visceral fat (AVF) area assessed by computed tomography was significantly correlated with all risk factors, except for fasting glucose, even after age, study cohort, and fat mass were taken into account. NW female subjects with at least one risk factor had a significantly higher AVF than those without risk factors, although the difference was small. Thus, only NW female adults with more AVF tended to have a more adverse CVD risk factor profile.

Echocardiographic epicardial adipose tissue is related to anthropometric and clinical parameters of metabolic syndrome: a new indicator of cardiovascular risk

Metabolic syndrome is related to multiple cardiovascular risk factors. Visceral adipose tissue (VAT) plays a key role in metabolic syndrome. Easy detection of VAT could be an important tool to increase knowledge of metabolic syndrome. The objective of this study was to study the relationship of echocardiographic epicardial adipose tissue to anthropometric and clinical parameters of metabolic syndrome. We selected 72 consecutive subjects, 46.5 +/- 17.4 yr of age, with a body mass index between 22 and 47 kg/m(2). Each subject underwent transthoracic echocardiogram to measure epicardial fat thickness on right ventricle and magnetic resonance imaging to calculate visceral adipose tissue. Anthropometric, metabolic, and cardiac parameters were also evaluated. Echocardiographic epicardial adipose tissue showed a very good correlation with magnetic resonance imaging abdominal VAT and epicardial fat measurement (Bland-Altman plot and linear regression). Multiple regression analysis showed that waist circumference (r(2) = 0.428; P = 0.01), diastolic blood pressure (r(2) = 0. 387; P = 0.02), and fasting insulin (r(2) = 0.387; P = 0.03) were the strongest independent variables correlated with epicardial adipose tissue. Echocardiographic epicardial adipose tissue could be applied as an easy and reliable imaging indicator of VAT and cardiovascular risk.

Adiponectin and metabolic syndrome

In this review article, the crucial roles of adipocytes in the development of so-called metabolic syndrome and vascular disease are reviewed, focusing on adipocyte-derived bioactive substances, adipocytokines. Recent progress in adipocyte biology shows that adipocytes are not merely energy-storing cells but that they secrete a variety of hormones cytokines, growth factors, and other bioactive substances. To search for novel adipocytokines by the large-scale random sequence analysis of expressed genes in adipocytes, we identified an adipose-specific collagen-like molecule, adiponectin. This novel adipocytokine has plural biofunctions, such as antidiabetic, antiatherosclerotic, and antiinflammatory functions. Adiponectin plasma levels decrease with the accumulation of visceral adipose tissue. In this review, we discuss the link of adiponectin to visceral adiposity, insulin resistance, and vascular diseases.

Detection of segmental internal fat by bioelectrical impedance analysis in a biological phantom

OBJECTIVE

Quantification of internal adipose tissue such as visceral adipose tissue currently relies on expensive, cross-sectional imaging modalities. The purpose of this study was to test the hypothesis that surface impedance, determined by bioimpedance analysis, might be used to predict regional internal fat content change in a phantom model.

METHODS

Fresh hollowed-out cucumbers were used as cylindrical biological phantoms to test this hypothesis. After removal of the seeds, the cucumbers were filled with normal saline, mixture of saline and corn oil, or porcine adipose tissue bathed in saline. Surface resistance and reactance were measured with a bioimpedance analyzer accurate to 0.1 Omega (Quantum 10X, RJL Systems), and impedance was calculated. A linear regression model was used to interpret the association between composition and impedance.

RESULTS

Surface impedance varied linearly with changes in the relative internal corn oil portions (r- = 0.98). A similar relation was noted with porcine adipose tissue bathed in saline (r(2) = 0.95) regardless of the specific position of adipose tissue within the cucumber.

CONCLUSION

Surface impedance measured by bioimpedance analysis can detect variations in fat content in the interior of a cylindrical phantom.

Relation of intra-abdominal fat distribution to metabolic disorders in nonobese patients with polycystic ovary syndrome

OBJECTIVE

To investigate the relation between intra-abdominal fat distribution and metabolic disorders in nonobese patients with the polycystic ovary syndrome (PCOS).

DESIGN

Prospective case-control study.

SETTING

University-based hospital.

PATIENT(S)

Thirty nonobese patients with PCOS and 30 lean women with regular menstrual cycles (controls). All participants had a body mass index < 25kg/m(2).

MAIN OUTCOME MEASURES

Subcutaneous and intra-abdominal visceral and preperitoneal fat thicknesses were assessed by ultrasonography. Glucose tolerance and insulin sensitivity were evaluated by standard 75-g oral glucose tolerance test and area-under-the-curve analysis. Serum hormones and lipid profile were measured.

RESULT(S)

The mean preperitoneal and visceral fat thicknesses were significantly greater in nonobese patients with PCOS. Subcutaneous fat mass was similar between the PCOS and control groups. Nonobese patients with PCOS had glucose intolerance, hyperinsulinemia, and dyslipidemia, manifested by high serum levels of triglyceride, total cholesterol, and high-density lipoprotein (HDL) levels and low serum low-density lipoprotein (LDL) levels. No correlation existed between subcutaneous fat thickness and the metabolic variables in nonobese patients with PCOS. However, serum triglyceride levels correlated with visceral fat and preperitoneal fat thickness. The mean HDL level correlated negatively with visceral fat and preperitoneal fat thickness. The area under the curve for insulin and mean fasting insulin levels correlated positively with visceral fat thickness. In multiple regression analysis, visceral fat thickness contributed significantly to high serum triglyceride and fasting insulin levels.

CONCLUSION(S)

Intra-abdominal preperitoneal and visceral fat accumulation may contribute to the development of glucose and lipid metabolism disorders in nonobese patients with PCOS.

Hemostatic variables, carbohydrate metabolism and lipid profile in women with low body mass index

The aim of this study was to evaluate hemostatic variables in women according to different body mass index (BMI) values, and then correlate them with some metabolic parameters - fasting insulin and glucose, total cholesterol, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol and triglycerides. Eighty-four female patients aged 18-39 years were recruited, and agreed to participate in the study. The study group was divided into three subgroups according to BMI: low BMI (BMI < 18.5 kg/m2; n = 43), normal-weight (control) (BMI 18.5-24.99 kg/m2; n = 21) and overweight/obese (BMI > 25 kg/m2; n = 20). BMI was calculated, and the following measurements were taken: International Normalized Ratio, antithrombin III, tissue plasminogen activator (t-PA) activity, t-PA-antigen, plasma fibrinogen level, factor VII, Plasminogen activator inhibitor (PAI)-1 activity and antigen and metabolic parameters: fasting insulin and glucose, total cholesterol, HDL-cholesterol, LDL-cholesterol and triglycerides. The results were statistically analyzed. In the low BMI group, a negative correlation between fasting insulin and PAI-1 activity, and a positive correlation between fasting glucose and PAI-1 antigen were observed. Also, a strong negative correlation between PAI-1 activity and insulin/glucose index was found. Plasma insulin levels were significantly lower in the low-BMI women than in the overweight/obese group (p < 0.001) and with no difference compared to the control group. We did not find any difference in fasting glucose level between all groups. HDL-cholesterol showed the highest levels in the normal BMI group and was significantly higher than in the low BMI and obese groups (p < 0.05 and p < 0.01, respectively). PAI-1 activity in the low BMI women revealed increased activity in comparison to control and overweight/obese women (p < 0.001 and p < 0.05, respectively). Lower antigen levels were also shown as compared to both these groups (p < 0.001 and p < 0.001, respectively). Similar results were obtained with t-PA antigen levels (p < 0.001 and p < 0.001, respectively). There were no differences in activity of t-PA in all groups. Obese women showed significantly higher fibrinogen levels than other BMI groups (p < 0.001 and p < 0.001 respectively). Analysis of hemostatic variables in women with a low BMI testify to the impaired fibrinolysis in this group, also showing a strong correlation with carbohydrate metabolism.

Pericardial anatomy for the interventional electrophysiologist

Investigators are beginning to exploit the pericardial space for a number of cardiovascular applications, including catheter ablation of cardiac arrhythmias, cardiovascular drug therapy, and cardiac pacing. This review explores the anatomy of the pericardial space and the anatomic variants that may be encountered in this novel approach to the heart.

Relationship between visceral fat accumulation and hypertension in obese men

PURPOSE

Visceral-fat (VF) accumulation is suggested to be a major contributor to such cardiovascular-disease risk factors as hypertension (H), glucose intolerance (G), and hyperlipidemia (L). We have devised a simple way of estimating VF accumulation, and investigated the relationship between VF and hypertension in obese men.

METHODS

First, CT scan was used to measure VF area in the umbilical region in 108 obese men. Then the umbilical-region circumference (C) was measured with a tape measure and abdominal skinfold thickness (S) with a skinfold caliper. The data obtained with a model formula (VFe = alphaC2 - betaCS + gamma) and actual VF area were compared, and three coefficients, alpha, beta, and gamma, were calculated by means of multivariate analysis. Next, in 354 male company employees, VFe was estimated using this model formula, and cardiovascular risk factors were investigated.

RESULTS

The formula for estimating VF (cm2) was VFe = 0.03C2 - 0.36CS - 47 (correlation coefficient; r = 0.72). Discriminant analysis between the merely obese group (O) and thegroup complicated by multiple cardiovascular risk factors (O, H, G, and L) determined a VFe-cutoff value of 120 cm2. Its discriminant sensitivity/specificity values were significantly higher than those based on body mass index (BMI) (cutoff value of 27 kg/m2) (p < 0.05). Hypertensive obese (HO) men with high VFe value (> 120 cm2) had a higher frequency of other risk factors (G or L: 86%).

CONCLUSION

VFe is considered useful in estimating VF accumulation, and seems more effective than BMI for predicting multiple cardiovascular risk factors (VF syndrome) in obese hypertensive men.

Comparison of body composition and periodontal disease using nutritional assessment techniques: Third National Health and Nutrition Examination Survey (NHANES III)

OBJECTIVES

The objective of this study was to investigate the association of body composition (obesity) and periodontal disease using simple, inexpensive nutritional assessment techniques available in the Third National Health and Nutrition Examination Survey (NHANES III).

MATERIAL AND METHODS

Caucasian subjects, aged 18 years and above, participating in NHANES III, were used for this study. Weight, height, waist circumference, hip circumference, skinfold thickness (S), and bioelectrical impedance analysis measurements were performed and used in the calculation of body mass index (BMI), waist-to-hip ratio (WHR) (visceral fat), log sum of S (subcutaneous fat), and fat-free mass (FFM). Data were analyzed using SPSS. One-way, factorial ANOVA, multivariate analyses, and regression curve analyses were performed. p<0.05 was used to reject the null hypothesis.

RESULTS

Adjusting for age, gender, history of diabetes, current smoking, and socioeconomic status, statistically significant correlations were found between periodontitis and WHR, BMI, FFM, and in some instances S.

CONCLUSION

This study, indicating significant correlations between body composition and periodontal disease (with WHR being the most significant, followed by BMI, FFM, and S), showed similarities to those observed in other obesity-related health problems. This strengthened arguments that periodontal disease and certain obesity-related systemic illnesses are related, with abnormal fat metabolism possibly being an important factor.

Association between abdominal wall fat index and carotid atherosclerosis in women

We tried to investigate whether accumulation of visceral fat assessed by a simple but widely used ultrasonography was associated with common carotid atherosclerosis in women. The subjects were consecutively admitted in-patients whose body mass index was more than 22 kg/m2. Those with cardiorenal or nutritional disorders that would affect blood pressure, and lipid and glucose metabolism were excluded. An ultrasonographic evaluation with a 7.5 MHz linear type B-mode probe was performed by a specialist to determine the intima-media thickness (IMT) of the common carotid artery and maximum thickness of preperitoneal fat (Pmax) at the anterior surface of the liver and the minimum thickness of subcutaneous fat (Smin) of the abdomen. The Pmax/Smin ratio which was termed the abdominal wall fat index (AFI), was then calculated. The subjects were 241 women aged 69 +/- 12 (range, 26-104) years. Multiple regression analysis using the IMT as an object variable, adjusted by various risk factors as explanatory variables showed that AFI [odds ratio, 2.995; 95% confidence interval, 1.106-8.109] was a significant independent contributing factor along with known risk factors such as age, systolic blood pressure, total-cholesterol, and HDL-cholesterol.AFI was useful in evaluating disorders of metabolism, circulation and atherosclerosis.

Elevated serum leptin concentrations in women with hyperuricemia

The serum uric acid level has been said to be an independent predictor of cardiovascular disease death, mainly for women, and to be linked with the metabolic Syndrome X of insulin resistance, obesity, hypertension, and dyslipidemia. Recently, it has been suggested that the elevation of serum leptin, the ob gene product, may have a role in metabolic Syndrome X. Therefore, we studied the relationship of uric acid to leptin in 822 Japanese women in a cross-sectional manner. To estimate the effect of uric acid on the variables of metabolic Syndrome X, we calculated mean values of various components of the syndrome according to tertiles of uric acid (UA < 4.0 mg/dl, 4.0 < or = UA < 5.5, 5.5 < or = UA). Age, systolic and diastolic blood pressure (BP), body mass index (BMI), percent body fat mass (BFM), serum total cholesterol, triglyceride, atherogenic index, leptin, fasting immunoreactive insulin and homeostasis model assessment-ratio (HOMA-R: calculated insulin resistance) were significantly different across the uric acid tertiles with higher levels in the highest tertile in comparison to the first (ANOVA, p < 0.001, 0.001, 0.002, 0.001, 0.001, 0.025, 0.001, 0.001, 0.001, 0.001, 0.001, respectively), while high density lipoprotein cholesterol showed lower levels (p < 0.001). Serum leptin concentrations were also elevated in hyperuricemic women after adjusting for BMI or BFM (both p < 0.001), and were weakly correlated with serum uric acid concentrations (r = 0.22, p < 0.0001). BMI, HOMA-R, serum triglyceride, diastolic BP and age-adjusted serum leptin concentrations were calculated for each tertile of serum uric acid. Compared with the lowest tertile of uric acid level, BMI, HOMA-R, serum triglyceride, diastolic BP and age-adjusted leptin concentrations were higher in the highest tertile. In the stepwise regression analysis, serum leptin was the significant independent variable for uric acid values. These results indicate an independent relationship between leptin and uric acid, further supporting the involvement of leptin in metabolic Syndrome X.

Report of the Japan Atherosclerosis Society (JAS) Guideline for Diagnosis and Treatment of Hyperlipidemia in Japanese adults

This paper described the Guideline for Diagnosis and Management of Hyperlipidemias for Prevention of Atherosclerosis proposed by The Japan Atherosclerosis Society (JAS) Guideline Investigating Committee (1,995-2,000) under the auspices of the JAS Board of Directors. 1) The guideline defines the diagnostic criteria for serum total cholesterol (Table 1), LDL-cholesterol (Table 1), triglycerides (Table 4) and HDL-cholesterol (Table 7). It also indicates the desirable range (Table 1), the initiation levels of management (Table 2) and the target levels of treatment (Table 2) for total and LDL-cholesterol. 2) Though both total and LDL-cholesterol are shown as atherogenic parameter in the guideline, the use of LDL-cholesterol, rather than total cholesterol, is encouraged in daily medical practice and lipid-related studies, because LDL-cholesterol is more closely related to atherosclerosis. 3) Elevated triglycerides and low HDL-cholesterol are included in the risk factors, since no sufficient data have been accumulated to formulate the guideline for these two lipid disorders. 4) Emphasis is laid on evaluation of risk factors of each subject before starting any kind of treatment (Table 2). 5) This guideline is applied solely for adults (age 20-64). Lipid abnormalities in children or the youth under age 19, and the elderly with an age over 65 have to be evaluated by their own standard. 6) This part of the guideline gives only the diagnostic aspects of hyperlipidemias. The part of management and treatment will follow in the second section of the guideline that will be published in future.

Epicardial fat from echocardiography: a new method for visceral adipose tissue prediction

OBJECTIVE

To validate transthoracic echocardiography as an easy and reliable imaging method for visceral adipose tissue (VAT) prediction. VAT is recognized as an important indicator of high cardiovascular and metabolic risk. Several methods are applied to estimate VAT, with different results.

RESEARCH METHODS AND PROCEDURES

We selected 60 healthy subjects (29 women, 31 men, 49.5 +/- 16.2 years) with a wide range of body mass indexes. Each subject underwent transthoracic echocardiogram and magnetic resonance imaging (MRI) to measure epicardial fat thickness on the right ventricle. Measurements of epicardial adipose tissue thickness were obtained from the same echocardiographic and MRI views and points. MRI was also used to measure VAT cross-sectional areas at the level of L4 to L5. Anthropometric indexes were also measured.

RESULTS

Subjects with predominant visceral fat accumulation showed higher epicardial adipose tissue thickness than subjects with predominant peripheral fat distribution: 9.97 +/- 2.88 vs. 4.34 +/- 1.98 (p = 0.005) and 7.19 +/- 2.74 vs. 3.43 +/- 1.64 (p = 0.004) in men and women, respectively. Simple linear regression analysis showed an excellent correlation between epicardial adipose tissue and waist circumference (r = 0.895, p = 0.01) and MRI abdominal VAT (r = 0.864, p = 0.01). Multiple regression analysis showed that epicardial adipose tissue thickness (r(2) = 0.442, p = 0.02) was the strongest independent variable correlated to MRI VAT. Bland test confirmed the good agreement between the two methods.

DISCUSSION

Epicardial adipose tissue showed a strong correlation with anthropometric and imaging measurements of VAT. Hence, transthoracic echocardiography could be an easy and reliable imaging method for VAT prediction.

Relationships of resting energy expenditure with body fat distribution and abdominal fatness in Japanese population

Body fat distribution and abdominal fatness are indicators of risks for coronary heart disease. However, the relationships between resting energy expenditure (REE) and the body fat distribution or the abdominal fatness are unclear. We examined the relationships of REE with whole-body fat distribution (waist, hip and waist-to-hip ratio: WHR) and abdominal fatness (intra-abdominal fat: IF and subcutaneous fat: SF) after adjustment for body composition. 451 men and 471 women were subdivided into two groups, 40-59 years: middle-aged group and 60-79 years: elderly group. REE was measured by an indirect calorimetry system. Percentage of fat mass (%FM), fat mass (FM) and fat-free mass (FFM) were assessed by a dual-energy x-ray absorptiometry method. The IF area (IFA) and SF area (SFA) at the level of the umbilicus were measured using computed tomography. Circumference of waist and hip were measured in a standing position. The WHR, waist circumference and SFA did not significantly (p>0.05) associate with the REE after adjusting for FM, FFM and age in any of the groups. The adjusted REE was significantly and inversely correlated with hip (r=-0.159, p<0.05) and IFA (r=-0.131, p<0.05) in the elderly men. These results suggest that lower REE may contribute to greater hip and IFA rather than WHR and waist in elderly men.

Effects of Radiation on Fatty Liver and Metabolic Coronary Risk Factors among Atomic Bomb Survivors in Nagasaki

In order to clarify the basic mechanism(s) linking radiation exposure and coronary heart disease (CHD), we here collected ultrasonographic data on fatty liver and measured levels of metabolic CHD risk factors from November 1990 through October 1992 in 1,517 Nagasaki atomic bomb survivors (575 men and 942 women). Using a cross-sectional study design, we examined the effects of radiation dose on fatty liver and CHD risk factors by means of a multiple logistic regression model. Fatty liver was related to the metabolic CHD risk factors associated with insulin resistance syndrome: obesity, hypertension, hypercholesterolemia, low high density lipoprotein (HDL)-cholesterol, hypertriglyceridemia, and abnormal glucose metabolism. Radiation dose was positively related to fatty liver, low HDL-cholesterol, and hypertriglyceridemia, whereas it had no effects on obesity, hypertension, hypercholesterolemia, or abnormal glucose metabolism. The present results suggested that radiation dose was related to 1) fatty liver, which clustered the metabolic CHD risk factors associated with insulin resistance syndrome and 2) atherogenic lipid profiles. It is suggested that these associations are involved in the basic mechanism(s) linking radiation exposure and CHD.

Insulin Resistance and Hypertension: Seven-Year Follow-Up Study in Middle-Aged Japanese Men (the KEIO Study)

Only a few longitudinal studies in Asians have shown a close association between hyperinsulinemia and the incidence of hypertension. In the present study, we used the insulin resistance index, HOMA-IR [fasting plasma glucose (FPG) (mmol/l) X insulin (microUl/ml) / 22.5], and tried to elucidate longitudinally the relationship among insulin resistance, blood pressure, body mass index (BMI), FPG, and lipid profile in middle-aged Japanese men. Three hundred and ten male non-hypertensive subjects aged 30 to 58 years in 1993 (44.5 +/- 7.8 (SD) years; BMI, 22.6 +/- 2.5 kg/m2) were divided into three groups according to HOMA-IR (A: lowest; B: middle; and C: highest). Their BMI, systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate, FPG and lipid profile were followed up for 7 years. The percentage of high normal blood pressure in 1993 and 2000 did not differ among the three groups. However, in 2000 hypertensive subjects made up 11.7% of group A (12/103), 15.4% of group B (16/104), and 29.1% of group C (30/103) (chi2 = 11.50, p = 0.003). SBP, DBP, and many other metabolic parameters in 2000 were significantly higher in group C than in the other groups. Furthermore, both SBP and DBP in 2000 were positively correlated with HOMA-IR in 1993 (r = 0.17 and p < 0.01 for both). The correlation between HOMA-IR in 1993 and DBP in 2000 was significant, even after adjustment for age and BMI in 1993. These findings suggest an important role of insulin resistance in predicting the future incidence of hypertension in middle-aged Japanese men.

Association of hypoadiponectinemia with coronary artery disease in men

BACKGROUND

Adiponectin is an adipocyte-derived plasma protein that accumulates in the injured artery and has potential antiatherogenic properties. This study was designed to determine whether a decreased plasma adiponectin level (hypoadiponectinemia) can be independently associated with the prevalence of coronary artery disease (CAD).

METHODS AND RESULTS

The consecutive 225 male patients were enrolled from inpatients who underwent coronary angiography. Voluntary blood donors (n=225) matched for age served as controls. Plasma adiponectin levels in the CAD patients were significantly lower than those in the control subjects. Multiple logistic regression analysis including plasma adiponectin level, diabetes mellitus, dyslipidemia, hypertension, smoking habits, and body mass index revealed that hypoadiponectinemia was significantly and independently correlated with CAD (P<0.0088). The entire study population was categorized in quartiles based on the distribution of plasma adiponectin levels. The interquartile cutoff points were 4.0, 5.5, and 7.0 microg/mL. The multivariate-adjusted odds ratios for CAD in the first, second, and third quartiles were 2.051 (95% confidence interval [CI], 1.288 to 4.951), 1.221 (95% CI, 0.684 to 2.186), and 0.749 (95%CI, 0.392 to 1.418), respectively.

CONCLUSIONS

Male patients with hypoadiponectinemia (<4.0 microg/mL) had a significant 2-fold increase in CAD prevalence, independent of well-known CAD risk factors.

New criteria for 'obesity disease' in Japan

The present study was designed to establish adequate criteria for categorizing 'obesity disease' in Japan in relation to obesity-related complications. The subjects were 1,193 Japanese subjects (775 men, 418 women; age: 20-84 years old, body mass index (BMI): 14.9-56.4 kg/m(2)) including subjects undergoing a health examination and obese subjects visiting an obesity clinic. Visceral fat area (VFA) and subcutaneous fat area (SFA) were determined by computed tomography (CT) at the umbilical level. Anthropometric parameters, including BMI, waist circumference (W), waist/hip circumference (W/H), ratio and waist circumference/body height (W/BH) ratio, were measured. Hyperglycemia, dyslipidemia, and hypertension were evaluated as obesity-related complications. The relationship between each parameter and the prevalence of the complications was investigated. The number of complications increased in accordance with BMI and the average value was greater than 1.0 at a BMI of 25. The best combination of the sensitivity and specificity for detecting subjects with multiple risk factors was a BMI of 25. BMI showed a close positive correlation with SFA (r=0.82), even for BMI > or =25 (r=0.77), but had a weaker correlation with VFA (r=0.54). The obese subjects with a BMI > or =25 had no correlation between BMI and VFA because of the wide individual variation of VFA. The number of disorders was greater than 1.0 at 100 cm(2) of VFA and the best combination of the sensitivity and specificity for determining subjects with multiple risk factors was 100 cm(2) of VFA. Between the simple anthropometric values and measurement of VFA, it was proven that W had the closest relationship with VFA in both men (r=0.68) and women (r=0.65). The regression line obtained from simple correlation analyses indicated that the W corresponding to 100 cm(2) of VFA was 84.4 cm in men and 92.5 cm in women. These data suggest that obesity is adequately specified as a BMI > or =25 in Japan where the prevalence and degree of obesity remains mild. It is reasonable to establish the cut-off point of VFA at 100 cm(2) as indicative of the risk of obesity-related disorders and a waist circumference of 85 cm in men and 90 cm in women approximates to this visceral fat mass.

Effects of nutrition on the cell survival and gene expression of transplanted fat tissues in mice

Fat tissue transplantation is a useful and common clinical technique in the plastic and reconstructive surgeries. To know the nutritional effects on the survival and maintenance of fat grafts, the weights of tissues and cell sizes, and the gene expressions in the fat tissues were analyzed 14 days after transplantation. The body weight and the plasma insulin level in high nutritional group (HNG) were significantly higher (p<0.05) than those in low nutritional group (LNG), respectively. The measurements of cell size showed that there were 32.5% distributed in the diameter less than 2 microm in LNG, significantly higher than 28.5% in HNG. There were 7.5% distributed in the diameter more than 6 microm in LNG, significantly lower than 10.0% in HNG. The mRNA levels of leptin, lipoprotein lipase, and beta(3)-adrenergic receptor were 2.0-, 1.5-, and 1.7-fold higher in HNG than those in LNG, respectively. The levels of hormone sensitive lipase and hexokinase 2 transcripts were not significantly different in both groups. These results show that the systemic nutritional status in host causes the changes of cell size and tissue weight as well as gene expression in the transplanted fat using mice model. The nutritional condition is probably important for the fat graft clinically both as lipid-storage and functional cells.