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Background: Visceral adiposity is generally considered to play a key role in the metabolic syndrome.Objective: To examine the relationship between directly measured visceral adiposity and the risk for incident hypertension, independent of other adipose depots and fasting plasma insulin levels.Design: Community-based prospective cohort study with 10- to 11-year follow-up.Setting: King County, Washington.Participants: 300 Japanese Americans with a systolic blood pressure less than 140 mm Hg and a diastolic blood pressure less than 90 mm Hg who were not taking antihypertensive medications, oral hypoglycemic medications, or insulin at study entry.Measurements: Abdominal, thoracic, and thigh fat areas were measured by using computed tomography. Total subcutaneous fat area was calculated as the sum of these fat areas excluding the intra-abdominal fat area. Hypertension during follow-up was defined as having a systolic blood pressure of 140 mm Hg or greater, having a diastolic blood pressure of 90 mm Hg or greater, or taking antihypertensive medications.Results: There were 92 incident cases of hypertension during the follow-up period. The intra-abdominal fat area was associated with an increased risk for hypertension. Multiple-adjusted odds ratios of hypertension for quartiles of intra-abdominal fat area (1 = lowest; 4 = highest) were 5.07 (95% CI, 1.75 to 14.73) for quartile 3 and 3.48 (CI, 1.01 to 11.99) for quartile 4 compared with quartile 1 after adjustment for age, sex, fasting plasma insulin level, 2-hour plasma glucose level, body mass index, systolic blood pressure, alcohol consumption, smoking status, and energy expenditure through exercise (P = 0.003 for quadratic trend). The intra-abdominal fat area remained a significant risk factor for hypertension, even after adjustment for total subcutaneous fat area, abdominal subcutaneous fat area, or waist circumference; however, no measure of these fat areas was associated with risk for hypertension in models that contained the intra-abdominal fat area.Limitations: It is not known whether these results pertain to other ethnic groups.Conclusions: Greater visceral adiposity increases the risk for hypertension in Japanese Americans. [ABSTRACT FROM AUTHOR]

Objective: Greater visceral adiposity, higher insulin resistance, and impaired insulin secretion increase the risk of type 2 diabetes. Whether visceral adiposity increases risk of impaired glucose tolerance (IGT) independent of other adipose depots, insulin resistance, and insulin secretion is not known., Research Design and Methods: Study subjects included 128 Japanese Americans with normal glucose tolerance at entry. Baseline variables included plasma glucose and insulin measured after an overnight fast and during a 75-g oral glucose tolerance test, fat areas by computed tomography, insulin secretion (incremental insulin response [IIR] [30 min insulin - fasting insulin]/30 min glucose), and insulin resistance index (homeostasis model assessment for insulin resistance [HOMA-IR])., Results: During the 10- to 11-year follow-up period, we confirmed 57 cases of IGT. Significant predictors of IGT included intra-abdominal fat area (IAFA) (odds ratio [OR] for a 1 SD increase 3.82, 95% CI 1.63-8.94 at a fasting plasma glucose [FPG] level of 4.5 mmol/l), HOMA-IR (2.41, 1.15-5.04), IIR (0.30, 0.13-0.69 at an FPG level of 4.5 mmol/l), the interactions of IAFA by FPG (P = 0.003), and IIR by FPG (P = 0.030) after adjusting for age, sex, FPG, and BMI. The multiple-adjusted OR of IAFA increased and that of IIR decreased as FPG level decreased because of these interactions. Even after adjustment for total fat area, total subcutaneous fat area, or abdominal subcutaneous fat area, all of these associations remained a significant predictor of IGT incidence., Conclusions: Greater visceral adiposity increases the risk of IGT independent of insulin resistance, insulin secretion, and other adipose depots in Japanese Americans.

Background: Despite having lower average body mass indexes (BMIs) than do whites, Asians are at high risk of type 2 diabetes, possibly because of their greater central adiposity. The criteria for identifying individuals at risk of obesity-related conditions are usually not population specific., Objective: Our goal was to determine whether the National Heart, Lung, and Blood Institute (NHLBI) overweight and obesity guidelines are useful for identifying diabetes risk in Japanese Americans., Design: This was a prospective, cohort study of 466 nondiabetic Japanese Americans [age: 52.2 +/- 0.6 y; BMI (in kg/m(2)): 24.1 +/- 0.2; +/- SEM]. Diabetes status at a 5-y follow-up visit was assessed with an oral-glucose-tolerance test., Results: Among 240 subjects aged < or = 55 y, incident diabetes was strongly associated with overweight (BMI > or = 25) at baseline [relative risk (RR): 22.4; 95% CI: 2.7, 183; adjusted for age, sex, smoking, and family history] and weight gain of > 10 kg since the age of 20 y (adjusted RR: 4.5; 95% CI: 1.4, 14.5). NHLBI definitions of central obesity (waist circumference > or = 88 cm for women and > or = 102 cm for men) were unsuitable for this population because only 15 of 240 subjects met these criteria. A waist circumference greater than or equal to the third tertile was associated with diabetes (adjusted RR: 5.4; 95% CI: 1.7, 17.0). Among 226 subjects aged >55 y, incident diabetes was not associated with BMI, weight gain, or waist circumference., Conclusions: NHLBI definitions are useful for identifying overweight Japanese Americans aged < 55 y who are at high risk of diabetes. Although central adiposity is an important risk factor, the guidelines for waist circumference are insensitive predictors of diabetes risk in this population.

We used a nonhuman primate model (Macaca nemestrina) of adolescent human pregnancy to characterize bone remodeling at midpregnancy and at weaning and the associated changes in bone mass. In this longitudinal study, 125 nulliparous females were followed through pregnancy, 6 months of lactation, and 3 months postweaning; 13 nonpregnant females served as controls. Between early pregnancy and midpregnancy, the whole body bone mineral increased. There was no significant change between midpregnancy and parturition. Between parturition and 3 months lactation, the animals lost 3.0% of their bone mineral (p < 0.01), which was regained by 3 months after weaning. The vertebral bone mineral apparent density decreased during pregnancy and 6 months of lactation, followed by an increase during the 3 months after weaning. Calcium, phosphate, 25-hydroxyvitamin D, and osteocalcin increased significantly from midpregnancy to weaning whereas 1,25-dihydroxyvitamin D values showed significant decreases. Histomorphometric measurements from bone biopsies showed significant increases in most parameters of bone formation between pregnancy and weaning. These results are consistent with the hypothesis that at midpregnancy bone formation is decreased and cancellous bone resorption may have increased. During lactation, losses occur in both cortical and cancellous bone, partially depleting the maternal reservoir of calcium, but a subsequent increase in bone formation enables restoration of bone mineral after weaning to values similar to those in the control group.

Objective: To examine the associations among visceral and subcutaneous adiposity, body-mass-index (BMI), fasting plasma insulin, lipid, and lipoprotein levels., Design: Cross-sectional observational study., Subjects: Non-diabetic second- (Nisei, n = 290) and third-generation (Sansei, n = 229) Japanese Americans., Measurements: Intra-abdominal (IAF) and subcutaneous abdominal fat (SAF) area were measured using computed tomography. Fasting plasma insulin, lipid, and lipoprotein levels were measured using standard methods., Results: Higher fasting insulin was significantly related to greater mean IAF and SAF area, plasma triglycerides, total HDL and HDL2 cholesterol in men and women of both generations. In a multiple linear regression analysis model among Nisei adjusted for gender, age, SAF, antihypertensive medication use, smoking, alcohol use, and exercise energy expenditure, IAF area and fasting insulin level were independently correlated with plasma triglycerides (IAF r = 0.22, fasting insulin r = 0.23), total HDL (IAF r = -0.29, fasting insulin r = -0.28), HDL2 (IAF r = -0.30, fasting insulin r = -0.27), and HDL3 cholesterol (IAF r = -0.19, fasting insulin r = -0.19). Among Sansei, similar associations were seen, except that fasting insulin was unrelated to total HDL or HDL3 cholesterol. These effects differed by gender in several instances., Conclusions: Both visceral adiposity and fasting insulin level are significantly and independently related to adverse levels of lipids and lipoproteins in both generations of nondiabetic Japanese Americans. The association between adverse lipid profile and visceral obesity is not mediated solely through detrimental effects of intra-abdominal fat deposition on fasting insulin level.

Glucose intolerance is associated with increased risk of coronary heart disease (CHD) in Japanese-Americans, especially in men. Intra-abdominal fat, assessed by computed tomography, is increased in those with both NIDDM and CHD. Increased intra-abdominal fat (visceral adiposity) with CHD is independent of NIDDM or impaired glucose tolerance. The association between NIDDM and CHD may be explained by the association of each of these conditions with visceral adiposity. However, hyperinsulinemia is associated with CHD only in the presence of diabetes, whereas triglyceride levels are elevated with CHD independent of glucose tolerance category. These findings suggest that factors other than insulin levels, such as lipids, may mediate the relationship between visceral adiposity and CHD. Moreover, these relationships are influenced by gender.

AMONG SEATTLE'S JAPANESE AMERICANS, hypertension is associated with older age, male gender (in the younger age groups), glucose intolerance (impaired glucose tolerance and diabetes), and visceral obesity (measured by computed tomography). The gender difference in prevalence of hypertension is absent in those ages 65 to 74 and in those with diabetes. In the absence of diabetes, hypertension is not associated with fasting plasma insulin levels in the older second generation, but it is in the younger third generation. The association of hypertension with plasma insulin in the third generation may be due to the association between diabetes and plasma insulin and the presence of many prediabetic individuals in this generation. About three-fourths of Japanese Americans are aware of their hypertension, slightly more than half of hypertensive Japanese Americans are being treated with anti-hypertensive medication, and of those receiving anti-hypertensive medication, less than half have their hypertension controlled. Women tend to be less aware of hypertension, to receive anti-hypertensive medication less often, and to have their hypertension less well-controlled than men.

There is good evidence that central (visceral) adiposity is important in the development of the insulin resistance or metabolic syndrome (obesity, hyperinsulinemia, dyslipidemia, glucose intolerance, hypertension, and coronary heart disease). It is proposed that some non-Caucasian populations are especially susceptible to development of this syndrome, and that lifestyle changes may play important etiologic roles. We postulate that this is due to the presence in these populations of a genetic predisposition to weight gain, perhaps related to a "thrifty" genotype, leading to the concentration of weight gain in visceral fat depots, when there is exposure to conditions associated with westernization.

Gender-related research directed to hypertension and coronary artery disease (CAD) is discussed in terms of the one-sex and two-sex models. Gender "blind" research on the two conditions has resulted in questionable treatment regimes for women. In addition, the biomedical myth of CAD as a male disease has also perpetuated less-than-optimal treatment. Finally, the role of amount and distribution of body fat in the development of hypertension and CAD should be considered within an evolutionary framework. Body fatness in women has been of evolutionary survival value and current standards for ideal weight and risk for disease have to take this into account. © 1995 Wiley-Liss, Inc., (Copyright © 1995 Wiley-Liss, Inc., A Wiley Company.)

In Seattle, Washington, the prevalence of diabetes was 20% in second-generation (Nisei) Japanese-American men and 16% in Nisei women 45-74 years old, while the prevalence of impaired glucose tolerance (IGT) was 36% in Nisei men and 40% in Nisei women. Hyperglycemia was less and duration of diabetes shorter in women. Related to diabetes and IGT in Nisei were higher fasting plasma insulin levels and central (visceral) adiposity. Prevalence of diabetes was low among the younger (34-53 years old) third-generation (Sansei) men and women. Among self-reported non-diabetic Sansei, however, prevalence of IGT was 19% in men and 29% in women, and IGT was associated with both increased fasting plasma insulin levels and more visceral fat, suggesting that many Sansei are at risk of future diabetes. An important lifestyle factor in the development of NIDD in Japanese Americans appeared to be dietary saturated (animal) fat. Another factor may be physical inactivity. In Japanese-American women, menopause also appeared to be an important risk factor. These risk factors may be related to fostering the accumulation of visceral fat and the development of insulin resistance. Five-year follow-up examinations performed in non-diabetic Nisei men and women have yielded additional information concerning the prognosis of IGT. Of those women who were IGT at baseline, 34% were diabetic at follow-up while 17% returned to normal. In men who had been IGT at baseline, 18% were diabetic at follow-up while 36% returned to normal. Over the 5-yr follow-up interval, proportionally more women progressed from normal to IGT (54%) then went from IGT to normal (17%). For men, roughly equal proportions went from normal to IGT (37%) as from IGT to normal (36%). It would therefore appear that greater proportions of Nisei women are progressing to IGT and to NIDD than are Nisei men. This observation may be related to the increased risk of developing central obesity and insulin resistance following menopause. Prevalence of cardiovascular disease (hypertension, peripheral vascular disease, and/or coronary heart disease) was increased in Japanese Americans with IGT and NIDD. Neuropathy and retinopathy were associated only with NIDD.

The hypothesis was tested that prenatal alcohol exposure disrupts developmental homeostasis, as reflected in increased dermatoglyphic fluctuating asymmetry. Twenty-two patients with fetal alcohol syndrome (FAS) and 9 with fetal alcohol effect (FAE) were matched for sex with 31 controls. On each patient, the right a-b dermal ridge count was subtracted from the left to obtain the asymmetry value. Group differences were tested by analysis of variance (ANOVA), and paired two-tailed t tests. Mean asymmetry increased from control (1.94) through FAE (2.78) to the FAS (4.00) group. Group differences were significant by ANOVA (p = 0.0066); only the FAS and control group differed by t test (p = 0.0025). The results support the hypothesis of increased decanalization of prenatal development in the presence of alcohol.

In a study sample of second generation Japanese American men (age range 45-74 years), family history of diabetes in a sibling or parent was present in 69 men (24 of 79 normal men and 45 of 78 type 2 diabetic men, P less than 0.001). Both general adiposity and body fat distribution have been associated with type 2 diabetes. Our hypothesis was that the association of both overall adiposity and of larger specific regional fat deposits with type 2 diabetes would differ depending upon family history. The relationships between diabetes and differences in general adiposity (whether current or maximum lifetime body mass index or BMI, sum of skinfolds, or sum of computed tomography or CT fat areas) and between diabetes and body fat distribution (measured as abdominal and thigh circumferences, cross-sectional body fat areas by CT of thorax, abdomen, and thigh, and skinfold thicknesses of triceps, biceps, forearm, chest, subscapula, abdomen, and thigh) were more apparent in those men without a family history of diabetes than in those with a family history. In men without a family history, diabetic men had significantly higher values for several variables which assessed overall adiposity: current BMI (P less than 0.001), maximum lifetime BMI (P less than 0.001), sum of skinfolds (P less than 0.006), and sum of CT fat areas (P less than 0.015). In addition several measurements of upper truncal adiposity were significantly increased in diabetic men: abdominal circumference (P less than 0.004), thoracic (P less than 0.015) and abdominal (P less than 0.03) subcutaneous CT fat areas, intra-abdominal CT fat areas (P less than 0.001), and chest (P less than 0.03) and subscapular (P less than 0.0002) skinfold thicknesses. The results pertaining to those without a family history appear to be due to increased adiposity and associated larger specific regional fat depots leading to diabetes and lesser adiposity and smaller amounts of fat in the same regional depots protecting against diabetes.

The growth and skeletal maturation of nine preterm female pigtailed macaques (Macaca nemestrina) obtained by C-section at less than or equal to 155 postconceptional days were followed through six months of age. At C-section they were of normal size and maturation for gestational age. Compared with 50 normal females born at term (mean = 173 +/- 6.4 postconceptional days), preterm infants were also of normal size at term, but delayed in skeletal maturation, requiring about one month to achieve the standard.

The order of appearance of the carpals, tarsals and secondary epiphyseal centers in the hand-wrist and foot-ankle regions of the fetal and infant pigtail macaque (Macaca nemestrina) was reconstructed using a cross-sectional sample of 127 animals and a longitudinal one of 14 animals. Comparison of the most common sequence in the monkey with that described in the human studies showed major interspecific differences in the order of appearance of several groups of centers, particularly those involving the thumb and great toe. The monkey displays a degree of sequence variability equivalent to that documented by the human longitudinal data, with certain centers markedly variable in timing and/or order of appearance. The evidence from related animals suggests a strong genetic component underlying some of the variable sequences observed, as has been reported in the human studies. The demonstrated variability in both timing and sequence precludes the use of specific centers in the determination of gestational age in fetuses of unknown conception date.

The data above, and the literature reviewed, demonstrate that in 4 significant morphological characteristics the neuro-skeletal topology of the human basicranial regions is unique, and does not resemble that of any extant non-human primate at any fetal or postnatal age. These characteristics are: 1. the shape of the cranial base; 2. the composition of the anterior and posterior portions of that base; 3. the extent, or degree, of basicranial flexion; and 4. the extent, or degree, of brain flexion. On these bases, the craniological implications of Bolk's fetalization hypothesis cannot be supported.