名古屋学芸大学健康 ･ 栄養研究所年報

創刊号

２００７年

《Original Article》

The Relation of Visceral Adipose Tissue to the Metabolic Syndrome
Motoji Kitagawa＊, Maki Kataoka＊, Masao Saito＊＊ and Akira Takahashi＊＊

Summary
Current study was undertaken to examine metabolic abnormalities in subjects with excess visceral adiposetissue. Three hundred seventy-six subjects (345 men and 31 women) for medical check-up were enrolled in
the present study. The amount of visceral and subcutaneous fat area (VFA and SFA) at umbilical level wasdetermined by computed tomography. The number of subjects with 25>BMI and 100cm2>VFA is 134 (113men and 21 women), with 25>BMI and 100cm2≦VFA is 102 (101 men and 1 woman), with 25≦BMI and100cm2>VFA is 27 (23 men and 4 women), with 25≦BMI and 100cm2≦VFA is 113 (108 men and 5 women).
Subjects with 100cm2≦VFA had significant higher levels of body weight, body mass index, systolic bloodpressure, diastolic blood pressure, fasting blood glucose, triglyceride, uric acid, ALT, and g GTP than subjects
with 100cm2>VFA. Serum HDL-cholesterol and amylase are significantly lower in subjects with excess
visceral fat. In the present study, male obese subjects have excess visceral fat. Hypertension, dyslipidemia
and glucose intolerance occur more frequently in subjects with excess visceral fat than in non-obese subjects.
The measurement of visceral fat area correlates more closely with the abnormalities of fasting blood glucose
and uric acid than BMI.

Introduction
The metabolic syndrome is a common metabolic disorder that results from the increasing prevalence ofobesity (1-3). The metabolic syndrome is also known as syndrome X, the insulin resistance syndrome, andthe deadly quartet. The constellation of metabolic abnormalities includes glucose intolerance (type 2 diabetes,impaired glucose tolerance, or impaired fasting glycemia), insulin resistance, central obesity, dyslipidemia ,and hypertension, all well documented risk factors for cardiovascular disease . These conditions co-occur in
an individual more often than might be expected by chance. When grouped together, they are associated withincreased risk of cardiovascular disease. Epidemiological studies often report a relation of excess visceral fat
to metabolic syndrome. In moderate obesity, regional distribution appears to be an important indicator for
metabolic and cardiovascular alterations since an inconstant correlation between body mass index (BMI) andtheir disturbances has been found (4-6).
In the present study, we investigated the correlation between visceral fat area and laboratory data of subjects examined for medical check-up, reflecting metabolic and cardiovascular diseases. We sought to identify
associations between the amount of excess visceral fat and metabolic abnormalities.

＊ School of Nutritional Sciences, Nagoya University of Arts and Sciences＊＊ Chubu Health Care Center (Nagoya)35

Subjects and Methods
Three hundred seventy-six subjects (345 men and 31 women) who visited the Chubu Health Center for
medical check-up in 2001 were enrolled in the present study. Mean age of subjects was 51 years old (range38 – 68).
The subjects’ height and weight were measured with a portable standiometer and a digital scale to thenearest 1mm and 0.1kg respectively. Blood pressure (BP) was measured in the seated position on the right arm
using an automated blood pressure recorder.
Blood samples were obtained from the antecubital vein of the subjects after overnight fasting. All subjectsunderwent the standard blood examination, including measurement of fasting glucose, hemoglobin A1C(HbA1C),
total cholesterol, HDL cholesterol, triglyceride, uric acid, AST, ALT, g GTP, amylase.
To determine the visceral intra-abdominal and subcutaneous abdominal areas, a simple CT scan wasundertaken at the level of the umbilicus. CT was used to assess the degree liver steatosis. Liver CT attenuations
were determined by calculating the mean Hounsfield unit (HU).
Data are expressed as means ± a standard deviation (SD). The difference of means between two groupswas assessed by Student’s t-test. Significance was taken as p<0.05. Statistical analyses were performed byusing Stat View software (version 5; Japanese Edition, SAS Inc).

Result
The number of subjects with 25 > body mass index (BMI) and 100cm2 > visceral fat area (VFA) is 134(113 men and 21 women), with 25 > BMI and 100cm2 ≦ VFA is 102 (101 men and 1 woman), with 25 ≦BMI and 100cm2 > VFA is 27 (23 men and 4 women), with 25 ≦ BMI and 100cm2 ≦ VFA is 113 (108 menand 5 women). In men, the prevalence of subjects with BMI≧25 is 62%, and with VFA≧100cm2 is 61%. In
women, the prevalence of subjects with BMI≧25 is 29%, and with VFA≧100cm2 is 19%.
Anthropometric and clinical laboratory data of subjects with VFA < 100cm2 and VFA ≧100cm2 are shownin Table 1. Subjects with VFA≧100cm2 had significant higher levels of body weight, BMI, systolic bloodpressure, diastolic blood pressure, fasting blood glucose, total cholesterol, triglyceride, uric acid, and ALT thanthose with VFA<100cm2. Serum HDL-cholesterol, amylase and CT number of the liver are significantly lower
in subjects with excess visceral fat.
Anthropometric and clinical laboratory data of subjects with BMI < 25 and BMI≧25 are shown in Table2.
Subjects with BMI≧25 had significant higher levels of body weight, systolic blood pressure, diastolic bloodpressure, total cholesterol, and triglyceride and ALT than those with BMI<25. Serum HDL-cholesterol andCT number of the liver are significantly lower in obese subjects. Subjects with BMI≧25 also had significant
higher value of visceral fat area and subcutaneous fat area than those with BMI<25.

Discussion
In the present study, we analyzed anthropometric and laboratory data of subjects having a medical checkup,
based on BMI and visceral fat area. Obesity is, of course, a great public health concern because it is directly
related to the development of diabetes, hypertension, dyslipidemia, and ultimately, cardiovascular diseases.
Obesity is usually based on the BMI. Several studies suggest that increased visceral adiposity is more likely
to be associated with metabolic alterations than simply an increased BMI (1-7). A strong positive correlation

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Metabolic Syndrome and Visceral Fat

Table 1. Anthropometric and clinical laboratory data of subjects with VFS<100cm2 and VFA ≧ 100cm2

Table 2. Anthropometric and clinical laboratory data of subjects with BMI<25 and BMI ≧ 25exists between the amount of visceral adipose tissue and the health risks of obesity. Regional distribution ofbody fat appears to be an important indicator for metabolic alterations since an inconstant correlation between
BMI and these disturbances has been found (4).
In this study, there are significant differences in serum level of blood pressure, total cholesterol, HDLcholesterol, triglyceride, ALT and CT number of the liver between obese and non-obese subjects evaluated byBMI, and between subjects with excess and normal visceral fat. There is no significant difference in serum levelof fasting blood glucose and uric acid between obese subjects and non-obese subjects evaluated by BMI. On thecontrast, subjects with excess visceral fat have higher levels of fasting blood glucose and serum uric acid thanthose with less amount of fat, based on visceral fat area evaluated by abdominal CT scan. Excess visceral fat

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seems to reflect glucose intolerance and abnormal uric acid metabolism more accurately than BMI. Matsuura etal (8) reported the relationship between uric acid metabolism and fat distribution. Visceral fat obesity was linked
more closely to overproduction of uric acid than subcutaneous fat obesity. Therefore, estimating the visceralfat accumulation is important in terms of evaluating obesity with a higher risk of metabolic disorders.
Some metabolic abnormalities including glucose intolerance, central obesity, dyslipidemia and hypertension
co-occur in an individual as metabolic syndrome, which is associated with an increased risk of cardiovasculardiseases. The measurement of the waist circumstance provides an estimate of body fat distribution (in lieu ofCT or MRI). In 2005, a committee of specialists from eight Japan Societies specified a diagnosis criterion ofJapan-specific metabolic syndrome appropriate for Japanese. According to this diagnostic criterion for Japanese(9), abdominal obesity : waist circumstance: ≧85 cm in men and ≧90 cm in women was obligatory since
central obesity, as opposed to BMI, may reflect the volume of fat around visceral organs. Excess fat in theintra-abdominal cavity is associated with an increased risk of hypertension, diabetes, dyslipidemia, and othercomplications, compared with the same amount of fat carried in the subcutaneous tissue. In the present study,
the prevalence of excess visceral adiposity (VFA≧100cm2) is 61% in men, and 19% in women. Urashima etal (10) reported that using data from the Health Science Center at Jikei University Hospital, the prevalence ofabdominal obesity (waist circumstance: ≧85 cm in men and ≧90 cm in women) is 46.2% in men and 12.3%
in women. One of the reasons of high prevalence of abdominal obesity in the present study is that the averageage of subjects in the present study is relatively high compared with Japanese general population. Moreover,considerable controversy has arisen as to the waist circumference cut-off points for diagnosing metabolic
syndrome for Japanese people (11, 12).
In conclusion, the estimation of visceral fat adiposity is more important to predict the aggravation of
glucose intolerance and uric acid metabolism than that of BMI. Further studies must be performed to elucidate
more suitable method for estimating visceral fat and appropriate criteria for metabolic syndrome for early
detection of the risk of cardiovascular diseases.

References1.

Eckel RH, Grundy SM, Zimmet PZ. The metabolic syndrome. Lancet 2005; 365: 1415-28.

2.

Kahn R, Ferrannini E, Buse J, Stern M. The metabolic syndrome: Time for a critical appraisal. Diabetes Care 2005; 28:2289-2304.

3.

Dandona P, Aljada A, Chaudhuri A, Mohanty P, Garg R. Metabolic syndrome. A comprehensive perspective based oninteractions between obesity, diabetes, and inflammation. Circulation 2005; 111: 1448-1454.

4.

Larsson B. Obesity, fat distribution and cardiovascular disease. Int J Obesity 1991; 15: 53-57.

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Wajchenberg BL. Subcutaneous and visceral adipose tissue: Their relation to the metabolic syndrome. Endocrine Review
2000; 21: 697-738.

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Karelis AD, St-Pierre DH, Conus F, Rabasa-Lhoret R, Poehlman ET. Metabolic and body composition factors in subgroupsof obesity: What do we know? J Clin Endocrinol Metab 2004; 89: 2569-2575.

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Miyawaki T, Abe M, Yahata K, Kajiyama N, Katsuma H, Saito N. Contribution of visceral fat accumulation to the risk
factors for atherosclerosis in non-obese Japanese. Intern Med 2004; 43: 1138-44.

8.

Matsuura F, Yamashita S, Nakamura T, Nishida M, Nozaki S, Funahashi T, Matsuzawa Y. Effect of visceral fat
accumulation on uric acid metabolism in male obese subjects: visceral fat obesity is linked more closely to overproductionof uric acid than subcutaneous fat obesity. Metabolism 1998; 47: 929-33.

9.

Definition and criterion of metabolic syndrome. Jpn Soc Int Med 2005; 94: 188-203. (in Japanese)

10. Urashima M, Wada T, Fukumoto T, Joki M, Maeda T, Hashimoto H, Oda S. Prevalence of metabolic syndrome in a 22,892

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Japanese population and its associations with life style. JMAJ 2005; 48: 441-450.
11. Hara K, Yokoyama T, Metsushita Y, Tanaka H, Horikoshi M, Kadowaki T, Yoshiike N. A proposal for the cutoff point ofwaist circumference for the diagnosis of metabolic syndrome in the Japanese population. Diabetes Care 2006; 29: 1123-24.
12. Hayashi T, Boyko EJ, McNeely MJ, Leonetti D, Kahn SE, Fujimoto WY. Minimum waist and visceral value for identifying
Japanese Americans at risk for the metabolic syndrome. Diabetes Care 2007; 30: 120-127.

和文抄録

内臓脂肪型肥満とその合併症の検討
北川＊

元二片岡麻希

＊

＊＊

斎藤征夫

高橋＊＊

玲

2001年に中部健康管理センターにおいて腹部 CT 検査を含めた職域検診を受診した376例を対象に BMI と内臓脂肪面積（VFA）により群分けを行い、身体計測値、血圧、空腹時血糖、HbA1c、総コレステロール、HDL コレステロール、トリグリセリド、尿酸、AST、ALT、γGTP、アミ22ラーゼについて比較検討した。BMI ＜25･VFA ＜100cm は134例、BMI<25･VFA ≧100cm は102例、22BMI ≧25･VFA ＜100cm は27例、BMI ≧25･VFA ≧100cm は113例であった。内臓脂肪型肥満患者では体重、BMI、収縮期血圧、拡張期血圧、空腹時血糖、総コレステロール、トリグリセリド、尿酸、ALT が有意に高値であった。一方、肝 CT 値、HDL コレステロール、アミラーゼは有意に低値であった。男性肥満患者では内臓脂肪型肥満の頻度が高かった。肥満患者のうち BMI によって判定した肥満者より内臓脂肪型肥満者に糖代謝異常、高尿酸血症を認める頻度が高かった。内臓脂肪型肥満者では生活習慣病の発症頻度が高く、糖尿病の合併症の発症に十分留意する必要がある。

＊名古屋学芸大学 管理栄養学部管理栄養学科＊＊全国土木建築国民健康保険組合中部健康管理センター

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