Showing papers on "Abdominal obesity published in 1998"
TL;DR: Interactions between diurnal cortisol secretion related to perceived stress and anthropometric, endocrine, metabolic, and hemodynamic variables seem to occur with apparently normal regulation of the HPA axis.
Abstract: Abdominal obesity has been suggested to be associated with perturbations of the regulation of the hypothalamic-pituitary-adrenal (HPA) axis. In a population of 51-yr-old men (n = 284) salivary cortisol concentrations were determined on repeated (n = 7) occasions over a random working day, and perceived stress was reported in parallel. Cortisol values were then related to reported stress (stress-related cortisol). A standardized lunch was used as a physiological challenge. A low dose (0.5 mg) dexamethasone suppression test was also performed as well as determinations of testosterone and insulin-like growth factor I (IGF-I). Body mass index [weight (kilograms)/height (meters)2]; waist/hip circumference ratio (WHR); sagittal trunk recumbent diameter (D); fasting insulin; blood glucose; triglycerides; and total, low density (LDL), and high density (HDL) lipoprotein cholesterol were also determined. Cortisol concentrations were highest in the morning, and lunch was followed by a peak (P = 0.044). Two types of diurnal cortisol curves were identified, one characterized by a high variability with high morning values, and another with low variability and low morning values. Both correlated strongly with suppression of salivary cortisol by dexamethasone (P < 0.001). Stress-related cortisol secretion was associated with D (P = 0.051), low IGF-I (P = 0.006), and diastolic blood pressure (P = 0.078). When the type of diurnal cortisol curve was taken into consideration by statistical weighting, stress-related cortisol secretion in subjects with high variability showed associations with testosterone (P < 0.001), D, total and LDL cholesterol, diastolic blood pressure (P < 0.001), fasting insulin (P = 0.039), and glucose (P = 0.030) as well as, negatively, triglycerides (P < 0.001). When weighted for a low variability of diurnal cortisol secretion, stress-related cortisol secretion showed strong negative relationships with IGF-I, testosterone, and HDL. Furthermore, strong, consistent relationships (all P < 0.001) were found with obesity factors (body mass index, WHR, and D), and with metabolic (insulin, glucose, triglycerides, and total and LDL cholesterol) as well as hemodynamic variables (systolic and diastolic blood pressure and heart rate). These results clearly show interactions between diurnal cortisol secretion related to perceived stress and anthropometric, endocrine, metabolic, and hemodynamic variables. This seems to occur with apparently normal regulation of the HPA axis (high morning peaks and variability as well as dexamethasone suppression of cortisol), where other endocrine variables are not affected. With a low diurnal cortisol variation and blunted dexamethasone suppression, indicating abnormal regulation of the HPA axis, perceived stress-dependent cortisol values were strongly related to perturbations of other endocrine axes as well as abdominal obesity with metabolic and hemodynamic abnormalities. Perturbations of the regulations of the HPA axis such as those described in combination with low dexamethasone suppressibility are known to follow long term overactivation of the axis by factors such as environmental stress.
978 citations
TL;DR: The modern epidemic of obesity, the strong association between obesity and comorbidities such as coronary heart disease, type 2 diabetes, hypertension, and dyslipidemia, and the health risks of abdominal obesity and adult weight gain are discussed.
Abstract: The United States is in the midst of an epidemic of obesity involving more than one third of the adult population. The prevalence of obesity increased by 40% between 1980 and 1990. Obesity is a chronic disease with a multifactorial etiology including genetics, environment, metabolism, lifestyle, and behavioral components. A chronic disease treatment model involving both lifestyle interventions and, when appropriate, additional medical therapies delivered by an interdisciplinary team including physicians, dietitians, exercise specialists, and behavior therapists offers the best chance for effective obesity treatment. Lifestyle factors such as proper nutrition, regular physical activity, and changes in eating behaviors should be coordinated by this team. This review addresses the modern epidemic of obesity, the strong association between obesity and comorbidities such as coronary heart disease, type 2 diabetes, hypertension, and dyslipidemia. In addition to obesity, the health risks of abdominal obesity and adult weight gain are discussed. The evidence that supports health benefits from modest weight loss (between 5% and 10% of body weight) is evaluated and the 5 key principles of effective obesity therapy are put forward. Obesity is a therapeutic challenge best met by teams of health care professionals, including dietitians and physicians, working together to deliver optimal treatment.
197 citations
TL;DR: The clinical data suggest that aldosterone participates in hypertension associated with the "Insulin Resistance Syndrome", and the adrenal in viscerally obese subjects may be driven by a secretagogue released from the liver by fatty acids from abdominal adipocytes.
Abstract: Plasma aldosterone levels were measured in adults whose body mass index ranged from lean to obese. Blood was drawn while subjects rested supine for 30-90 minutes. Aldosterone was higher in obese subjects, but could not be explained by renin or K+. The best predictors of plasma aldosterone were abdominal obesity measured as waist/hip ratio or by CT scan, and insulin resistance measured by insulin or oral glucose tolerance tests, or euglycemic clamp. In one cohort, these correlations were limited to women; in the other, they were also found in men. In the women with a strong correlation between aldosterone and visceral fat, aldosterone also correlated with cortisol and DHEA-S. The data are consistent with an effect of visceral fat on adrenal steroidogenesis. Visceral adipocytes have a high rate of triglyceride turnover, and their circulation drains directly to the liver. In an experiment based on these characteristics, rat hepatocytes responded to fatty acids by releasing an unidentified secretagogue that stimulated aldosterone production by rat adrenal glomerulosa cells. The clinical data suggest that aldosterone participates in hypertension associated with the "Insulin Resistance Syndrome". The adrenal in viscerally obese subjects may be driven by a secretagogue released from the liver by fatty acids from abdominal adipocytes.
145 citations
TL;DR: This review summarizes the evidence that metabolic complications seen in individuals with abdominal obesity may account to a large extent for the increased risk of cardiovascular disease associated with abdominal/visceral obesity.
Abstract: Although the health hazards of obesity are well established, obese individuals are not all at equal risk of developing a disease, which reflects the heterogeneity of this condition. The regional distribution of body fat is now recognized as a very important component of the obesity-related health hazards. Epidemiological studies have shown that abdominal obesity, that is, a preponderance of fat in the abdominal area, is a better predictor of both cardiovascular disease and type 2 diabetes than obesity per se. It is now generally accepted that the fat located within the abdominal cavity, the visceral fat, is the best correlate of most of the highly atherogenic metabolic complications seen in individuals with abdominal obesity. These include, among others, insulin resistance and hyperinsulinaemia, hypertriglyceridaemia, reduced plasma high-density lipoprotein (HDL) cholesterol concentrations and an increased number of small, dense low-density lipoprotein (LDL) particles. This review summarizes the evidence that these metabolic complications may account to a large extent for the increased risk of cardiovascular disease associated with abdominal/visceral obesity. Abdominal obesity may be the most prevalent denominator of highly atherogenic dyslipidaemic and hyperinsulinaemic/insulin-resistant states in affluent, sedentary societies. Targeting individuals with this high-risk trait in primary prevention is therefore crucial if we are truly to have an impact on the incidence of cardiovascular disease.
136 citations
TL;DR: Intervention studies demonstrate that correction of relative hypogonadism in men with visceral obesity and other manifestations of the metabolic syndrome seem to decrease the abdominal fat mass and reverse the glucose intolerance, as well as lipoprotein abnormalities in the serum.
Abstract: Central or visceral obesity is recognized as a main risk factor for cardiovascular disease and type 2 diabetes mellitus. The co-existence of visceral obesity, increased blood lipid levels, hypertension and impaired glucose tolerance defines the metabolic syndrome that today is widely recognized as one of the prime factors behind cardiovascular morbidity and mortality. Endocrine disorders such as insulinoma, hypothyroidism and hypercortisolism are known to cause obesity. However, it is only hypercortisolism that is associated with increased abdominal fat accumulation. Recently, new findings have shed light on subtle endocrinopathies that are prevalent in individuals presenting with the metabolic syndrome. Such derangements are of borderline character and often fall within the normal reference range. Intervention studies demonstrate that correction of relative hypogonadism in men with visceral obesity and other manifestations of the metabolic syndrome seem to decrease the abdominal fat mass and reverse the glucose intolerance, as well as lipoprotein abnormalities in the serum. Further analysis of the underlying mechanism has also disclosed a regulatory role for testosterone in counteracting visceral fat accumulation. Longitudinal epidemiological data demonstrates that relatively low testosterone levels are a risk factor for development of visceral obesity. The primary event that triggers the initial development of visceral obesity is not known, but it seems plausible that increased activity in the hypothalamus-pituitary-adrenal axis can be of major importance.
107 citations
TL;DR: Results of the present study provide support for the notion that the hyperinsulinemic-insulin-resistant state of abdominal obesity is a powerful predictor of CAD in men, even in a group of patients with raised LDL cholesterol concentrations due to FH.
Abstract: Background—Patients with a mutation in the LDL receptor gene (familial hypercholesterolemia, or FH) are characterized by substantial elevations in plasma LDL cholesterol and are at higher risk of d...
95 citations
TL;DR: It is proposed that the less degree of abdominal adiposity observed in black males is related with an increased anti-lipolytic effect of insulin, which could account for low triglycerides and high HDL cholesterol levels, and consequently explain the higher protection from coronary heart disease experienced by black males compared with whites and black females.
Abstract: Black people in the UK, in the Caribbean, and to a lesser extent in the USA, experience coronary heart disease events at different rates than white people. Despite having higher prevalence of hypertension, cigarette smoking and diabetes, black males have significantly lower coronary heart disease rates than white males, whereas no significant differences have been detected in females. The only known risk factor differences that could account for the difference in CHD rates are higher HDL cholesterol and lower triglycerides that are seen in blacks compared with whites. Obesity and, in particular abdominal obesity, seems to determine TG and HDL cholesterol levels: black males are less centrally obese than whites, while total adiposity and central distribution of fat is more predominant in black females compared with white females. We propose that the less degree of abdominal adiposity observed in black males is related with an increased anti-lipolytic effect of insulin, which could account for low triglycerides and high HDL cholesterol levels, and consequently explain the higher protection from coronary heart disease experienced by black males compared with whites and black females.
93 citations
TL;DR: In this paper, the authors carried out population and intra-family association studies in individuals with Type II (non-insulin-dependent) diabetes mellitus, using a polymorphic marker (LIPE) in the HSL gene.
Abstract: Impaired lipolysis has been proposed as a pathogenic factor contributing to clustering of abdominal obesity and dyslipidaemia in Type II (non-insulin-dependent) diabetes mellitus – that is, the metabolic syndrome (MSDR). As this syndrome clusters in families, alterations in the hormone-sensitive lipase (HSL) gene could contribute to the genetic predisposition to MSDR. To test this hypothesis we carried out population and intrafamily association studies in individuals with MSDR, using a polymorphic marker (LIPE) in the HSL gene. There was a significant difference in allele frequency distribution between 235 Type II diabetic patients and 146 control subjects (p = 0.002), particularly between 78 abdominally obese Type II diabetic patients with MSDR and the control group (p = 0.010). An extended transmission disequilibrium test (TDT) showed transmission disequilibrium of 66 alleles to 42 nondiabetic, abdominally obese offspring in families with Type II diabetes (p < 0.05). A slight difference in allele frequency distribution was seen between 71 individuals from the lowest and 71 from the highest tertile of isoprenaline-induced lipolysis in fat tissue (p = 0.07). No missense mutations were found with single-strand conformational polymorphism (SSCP) in 20 abdominally obese subjects with MSDR. In conclusion, our population and intrafamily association studies suggest that the LIPE marker in the HSL gene is in linkage disequilibrium with an allele and/or gene which increases susceptibility to abdominal obesity and thereby possibly to Type II diabetes. [Diabetologia (1998) 41: 1516–1522]
88 citations
TL;DR: The results suggest that elevated BMI (obesity) and elevated WHR (central fat distribution) are associated in different ways with symptoms of psychiatric ill-health in women, suggesting gender differences in these associations.
Abstract: Objective: Abdominal obesity is associated with serious, prevalent diseases. Previously, psychiatric symptoms and ill-health has been found in this condition in men. The results of a similar study in women is reported herein.
Research Methods and Procedures: A cohort of 1464 women, aged 40 years and recruited by systematic sampling, was examined (77.7% participation rate). Items regarding use of anxiolytics, hypnotics, and antidepressive drugs were registered, as well as symptoms of dyspepsia, sleeping disturbances, melancholy, and degree of life satisfaction. Smoking and alcohol consumption, as well as self-measured weight, height, waist, and hip circumferences, were reported, from which body mass index [BMI; weight (kg)/height2 (m2), kg/m2] and the waist/hip circumference ratio (WHR) were calculated.
Results: In bivariate analyses, BMI was associated with use of anxiolytics, antidepressive drugs, various sleeping disturbances, and a low degree of life satisfaction. After controlling for “the WHR, alcohol, and tobacco use in multivariate analysis, the associations between BMI and use of anxiolytics and sleeping disturbances remained significant. The WHR correlated with dyspepsia, sleeping problems, and use of antidepressive drugs. After adjustments for BMI, smoking, and alcohol, the relationship to dyspepsia and antidepressants remained significant.
Discussion: The results suggest that elevated BMI (obesity) and elevated WHR (central fat distribution) are associated in different ways with symptoms of psychiatric ill-health in women. Obesity alone shows no such relationships to psy chiatric ill-health in men, whereas central fat distribution shows independent associations to all of the measured variables studied in this report in women, suggesting gender differences in these associations.
86 citations
TL;DR: There is a subgroup with elevated BMI, WHR, and D in whom a blunted dexamethasone response is found associated with traits of anxiety and depression, conditions characterized by such an abnormality.
Abstract: Abdominal obesity, anxiety, and depression have been found to cluster in several studies. To further characterize these associations, the following study was performed. In a population of 51-year-old men (N = 284), measurements of obesity (body mass index [BMI]) and body fat distribution (waist to hip ratio [WHR] and sagittal trunk recumbent diameter [D]) were analyzed in relationto dexamethasone (0.5 mg) inhibition of cortisol secretion, measured as salivary cortisol. Symptoms of anxiety and depression were defined by a validated questionnaire. Furthermore, testosterone, insulin-like growth factor-I (IGF-I), insulin, glucose, and serum lipid levels were measured. Twenty-five men (8.8%) had symptoms of anxiety and depression. BMI, WHR, and D correlated negatively with testosterone, except for BMI in the anxio-depressive (ADP) group. IGF-I showed no significant relationship. Furthermore, fasting insulin and the insulin to glucose ratio correlated positively and high-density lipoprotein (HDL) cholesterol correlated negatively with BMI, WHR, and D in the total study population and in the subgroups. Total and low-density lipoprotein (LDL) cholesterol showed no significant relationships. Correlation coefficients tended to be higher in ADP men. Dexamethasone inhibition showed a negative significant relationship with BMI (ρ = −.47, P = .025), WHR (borderline, ρ = −.37, P = .086), and D (ρ = −.43, P = .046) only in the ADP group. Comparing the ADP group versus the group without anxio-depression (ADO) and high or low BMI ( P = .008), WHR ( P = .026), and D ( P = .012) showed blunted dexamethasone inhibition only in ADP men with high anthropometric measurements. These findings suggest there is a subgroup with elevated BMI, WHR, and D in whom a blunted dexamethasone response is found associated with traits of anxiety and depression, conditions characterized by such an abnormality. The reason for the association might be insufficient control of cortisol secretion, followed by visceral fat accumulation.
79 citations
TL;DR: Abdominal obesity seems to be dependent on endocrine abnormalities, which in turn show direct or indirect relationships to the metabolic and circulatory variables, including a direct pathway between HPA-axis perturbations and accumulation of total body fat as indicated by the BMI.
Abstract: The interactions between hypothalamic-pituitary-adrenal axis activity, testosterone, insulin-like growth factor I and abdominal obesity with metabolism and blood pressure in men
TL;DR: It is suggested that general and central obesity is independently related to blood pressure, and that insulin may account for only part of this association.
Abstract: Objective Some studies have shown a clustering of obesity, insulin and hypertension. The present study was performed to further characterize these associations. Subjects and methods In a population of 51-year-old men (n = 284), measurements of systolic and diastolic blood pressure were analyzed in relation to general obesity (body mass index) and central obesity (waist : hip circumference ratio and abdominal sagittal diameter), and to the fasting insulin and insulin : glucose ratio as an approximation of insulin sensitivity. The regulation of diurnal cortisol secretion was examined in repeated salivary samples. Results Linear regression analysis showed that all three parameters of obesity were significantly and strongly related to both systolic and diastolic blood pressure, more powerfully than insulin, glucose and insulin sensitivity (insulin : glucose ratio). Stepwise multiple regression showed that only central obesity, measured as the abdominal sagittal diameter, remained significantly (P<0.001), and independently of insulin and insulin sensitivity, associated with both systolic and diastolic blood pressure (β = 7.5 and 4.2, respectively). A diurnal cortisol curve with normal rhythm was associated with lower than average blood pressures (P<0.001) but not with insulin levels or the heart rate. In contrast, a flattened diurnal cortisol curve, indicating perturbations in the activity of the hypothalamic-pituitary-adrenal axis, was directly related to blood pressures, heart rate and insulin (P<0.001), and has previously been found to be strongly associated with abdominal obesity. Conclusions These findings suggest that general and central obesity is independently related to blood pressure, and that insulin may account for only part of this association. The activity of the hypothalamic-pituitary-adrenal axis is apparently important for blood pressure regulation, suggesting that mechanisms of the central nervous system have an impact.
TL;DR: Defects of insulin action manifested as abdominal obesity, impaired NEFA suppression, and fasting hyperinsulinemia are present in Sikh MI patients and their asymptomatic, nondiabetic, first-degree relatives and it is suggested that these defects may be early metabolic markers that predict risk of premature MI among PSs.
Abstract: British Indian Asian men aged .05) MI patients compared with respective ethnic control subjects. Fasting glucose and total cholesterol levels did not differ between patients and control subjects. Abdominal obesity, impaired NEFA suppression after oral glucose, and fasting hyperinsulinemia were present in Sikh MI patients and their nondiabetic first-degree relatives compared with Sikh control subjects. PS survivors of premature MI demonstrated impaired insulin-mediated glucose disposal and NEFA suppression compared with ethnic control subjects. BWMI patients showed abnormalities of carbohydrate, but not of NEFA, metabolism compared with white control subjects. Defects of insulin action manifested as abdominal obesity, impaired NEFA suppression, and fasting hyperinsulinemia are present in Sikh MI patients and their asymptomatic, nondiabetic, first-degree relatives. We suggest that these defects may be early metabolic markers that predict risk of premature MI among PSs.
TL;DR: A higherbeta-AR affinity and lower alpha2-AR relative to beta-AR density may explain the higher in vitro catecholamine-mediated lipolysis in abdominal compared with gluteal adipocytes in obese, postmenopausal women.
Abstract: In women there is an increase in visceral obesity, subcutaneous abdominal adipocyte lipolysis, and risk of cardiovascular disease (CVD) associated with weight gain after menopause. The mechanisms underlying this increase in adrenoreceptor (AR)-agonist catecholamine-stimulated lipolysis and abdominal obesity in postmenopausal women were studied in intact adipocytes isolated from the abdominal and gluteal subcutaneous fat depots in 19 obese (48% +/- 1% body fat, mean +/- SE) women with a mean +/- SE age of 58 +/- 1 years. The fat cell size and adipose tissue lipoprotein lipase (ATLPL) activity were similar in both sites. The maximal lipolytic responsiveness and sensitivity to isoproterenol were higher (P < .05) in abdominal compared with gluteal adipocytes, but maximal lipolytic response to a post-AR agent was similar. Abdominal adipocytes had a higher beta-AR ([3H]-CGP-12177) and alpha2-AR ([3H]-yohimbine) affinity than gluteal cells (P < .05), lower alpha2-AR density (P < .05), but similar beta-AR density as gluteal cells. Both abdominal and gluteal cell size correlated with alpha2-AR density (P < .01), but not with beta-AR density. Thus, a higher beta-AR affinity and lower alpha2-AR relative to beta-AR density may explain the higher in vitro catecholamine-mediated lipolysis in abdominal compared with gluteal adipocytes in obese, postmenopausal women.
TL;DR: The extent to which regularly performed exercise can effect nutritional needs and functional capacity in the elderly is discussed and some basic guidelines for beginning an exercise program for older men and women, and establishing community-based programs are provided.
Abstract: Advancing age is associated with a remarkable number of changes in body composition. Reductions in lean body mass have been well characterized. This decreased lean body mass occurs primarily as a result of losses in skeletal muscle mass. This age-related loss in muscle mass has been termed sarcopenia. Loss in muscle mass accounts for the age-associated decreases in basal metabolic rate, muscle strength, and activity levels, which, in turn is the cause of the decreased energy requirements of the elderly. In sedentary individuals, the main determinant of energy expenditure is fat-free mass, which declines by about 15% between the third and eighth decade of life. It also appears that declining caloric needs are not matched by an appropriate decline in caloric intake, with the ultimate result an increased body fat content with advancing age. Increased body fatness along with increased abdominal obesity are thought to be directly linked to the greatly increased incidence of Type II diabetes among the elderly. This review will discuss the extent to which regularly performed exercise can effect nutritional needs and functional capacity in the elderly. In addition, some basic guidelines for beginning an exercise program for older men and women, and establishing community-based programs are provided.
Journal Article•
TL;DR: Evidence is presented that hypertriglyceridemia, particularly when associated with reduced high density lipoprotein (HDL) cholesterol concentrations and abdominal or visceral obesity, is a highly atherogenic phenotype, one that requires aggressive risk reduction management.
TL;DR: The results suggest that the presence of the Trp64Arg mutation contributes to obesity and hyperglycemia in the female population.
Abstract: The Trp64Arg mutation of the β 3 -adrenergic receptor (β 3 -AR) has been linked to earlier onset of non—insulin-dependent diabetes mellitus (NIDDM), insulin resistance, abdominal obesity, and an increased capacity to gain weight in some European and Japanese populations. We studied the prevalence of the mutation and its association with NIDDM and obesity in our population, in which both rates are high, especially in women. The frequency of the homozygous mutation was 1.53%, and of the Arg allele, 10.5%. Rates were similar in men and women. Significantly higher body mass index (BMI), weight, hip circumference, and fasting and postchallenge 2-hour blood glucose concentrations were associated with the presence of the Arg allele in women but not in men. The association with weight and hip measurements and with hyperglycemia was present only in women aged less than 55 years. In multivariate analysis, the mutation was associated with the BMI and sex in a model that also included age. The variation in fasting and 2-hour blood glucose levels was predicted by β 3 -AR, gender, age, and BMI. These results suggest that the presence of the mutation contributes to obesity and hyperglycemia in our female population.
TL;DR: It is suggested that this fits for women but not men, citing results from a survey centred on Glasgow that found no social gradient in the prevalence of abdominal obesity among men.
Abstract: Editor—In their discussion of diet as an important mediator of socioeconomic differences in health, James et al point to abdominal obesity as a biological factor responsible for the excess of cardiovascular disease and diabetes among groups of lower socioeconomic status.1 They suggest that this fits for women but not men, citing results from a survey centred on Glasgow that found no social gradient in the prevalence of abdominal obesity among men.2 However, other surveys in Britain, and from other industrialised countries, have found a …
TL;DR: In abdominally obese men with insulin resistance, it was demonstrated that most of the individual variability in serum leptin concentration was explained by the amount of subcutaneous abdominal adipose tissue, insulin sensitivity, and BMI.
Abstract: JOHANNSSON, GUDMUNDUR, CECILIA KARLSSON, LARS LONN, PER MARIN, PER BJORNTORP, LARS SJOSTROM, BJORN CARLSSON, LENA M.S. CARLSSON, BENGT-AKE BENGTSSON. Serum leptin concentration and insulin sensitivity in men with abdominal obesity. Obes Res. 1998;6:416–421.
Objective: We have examined the association between generalized adiposity, abdominal adiposity, insulin sensitivity, and serum levels of leptin in a cross-sectional study of abdominally obese men.
Research Methods and Procedures: Thirty men, 48 to 66 years of age with a body mass index (BMI) of between 25 kg/m2 and 35 kg/m2 and a waist hip ratio of <0.95, were included in the study. Serum leptin concentration was measured using radioimmunoassay. Total body fat percentage was determined from total body potassium, abdominal adiposity was measured by computed tomography, and the glucose disposal rate (GDR) was measured during an euglycemic, hyperinsulinemic glucose clamp.
Results: Significant correlations were found between serum leptin concentration and BMI, percentage body fat, abdominal subcutaneous adipose tissue, serum insulin, GDR, and 24-hour urinary-free Cortisol. In a multiple regression analysis, it was shown that abdominal subcutaneous adipose tissue, GDR, and BMI explained 72% of the variability of serum leptin concentration. GDR demonstrated an independent inverse correlation with serum leptin concentration.
Discussion: In abdominally obese men with insulin resistance, it was demonstrated that most of the individual variability in serum leptin concentration was explained by the amount of subcutaneous abdominal adipose tissue, insulin sensitivity, and BMI.
TL;DR: The data would suggest that in O and OD patients, insulin resistance is associated with elevated NEFA, insulin and glucagon as well as with high BP.
TL;DR: The hypothesis that peninsular Arabs and South Asians share a tendency to insulin resistance, differing from other ethnic groups living in the United Arab Emirates (UAE), is tested.
Abstract: Summary objective To test the hypothesis that peninsular Arabs and South Asians share a tendency to insulin resistance, differing from other ethnic groups living in the United Arab Emirates (UAE).
methods A representative sample of 358 apparently healthy men aged 35–49 years drawn from a multi-ethnic office-based workforce in the UAE was tested. The sample included a reference group of expatriate South Asians, in whom insulin resistance has already been described as the cause of high coronary heart disease (CHD) mortality. All subjects were screened for CHD risk factors, including glucose tolerance and 2-h serum insulin determinations.
results There was a high prevalence of previously undiagnosed cases of diabetes (10.1%) and hypertension (14.2%). South Asian and peninsular Arab men shared the tendency to significantly higher 2-h glucose and insulin levels, lower HDL cholesterol concentrations and abdominal obesity especially compared to Europeans, who were five times less likely to be glucose-intolerant (OR 5.40, P = 0.015). Three other Arab groups were intermediate in most trends.
conclusion Susceptibility to insulin resistance in Arabian peninsula men is strongly supported, suggesting that control of obesity and promotion of exercise are the best approach to CHD prevention.
TL;DR: Troglitazone, the first in a new class of drugs, directly decreases insulin resistance by improving insulin‐mediated glucose disposal and reduces plasma insulin concentrations and when combined with these agents offers additional plasma glucose reduction.
Abstract: Insulin resistance is characterized by impaired responsiveness to endogenous or exogenous insulin and often results in the insulin resistance syndrome, a clustering of cardiovascular risk factors that includes abdominal obesity, hypertension, dyslipidemia, glucose intolerance, and hyperinsulinemia. Although the mechanism responsible for insulin resistance has not been completely defined, it is likely due to defective insulin receptor signaling and results in decreased use of glucose. Troglitazone, the first in a new class of drugs, directly decreases insulin resistance by improving insulin-mediated glucose disposal and reduces plasma insulin concentrations. Glycemic control achieved with troglitazone monotherapy is equivalent to that with sulfonylurea and metformin, and when combined with these agents offers additional plasma glucose reduction. Studies are necessary to determine the effect of thiazolidinediones on morbidity and mortality of patients with type 2 diabetes and insulin resistance.
Journal Article•
TL;DR: Analysis of numerous studies have now revealed that the usual risk factors i.e. hypertension, hypercholesterolemia, obesity, smoking and a family history of CHD, are not common among South Asians, and guidelines for prevention as laid down by the American Heart Association may not be applicable in this population.
Abstract: Contrary to popular belief that coronary heart disease (CHD) is uncommon in developing countries, Asian Indians have among the highest prevalence of CHD. Analysis of numerous studies have now revealed that the usual risk factors i.e. hypertension, hypercholesterolemia, obesity, smoking and a family history of CHD, are not common among South Asians. Rather, they possess a different risk factor profile characterized by high triglycerides, low HDL, glucose intolerance, insulin resistance, abdominal obesity and increased lipoprotein(a) levels. On account of this difference and the alarming explosion of CHD in India, guidelines for prevention of CHD as laid down by the American Heart Association may not be applicable in our population. A judicious diet incorporating commonly used Indian food items and regular exercise will go a long way in effective primary prevention.
TL;DR: The data indicate that adrenal androgen secretion following low-dose ACTH administration in premenopausal women does not seem to be a function of body fat mass, fat distribution and insulin levels, nor does it correlate with the capacity of the adrenal glands to secrete cortisol in both basal and stimulated conditions.
Abstract: To investigate whether obese female subjects with abdominal obesity may have adrenal androgen hypersecretion, we examined two groups of women with abdominal (n = 12) and peripheral (n = 13) obesity (defined by body mass index and waist-to-hip ratio) and a group of seven healthy normal-weight women. All subjects underwent the following protocol study that included a) baseline determination of major adrenal androgens, b) an ACTH test, performed by administering two boli of ACTH (Synacthen, 0.2 microg/Kg BW, e.v.), at 90 min intervals, with blood samples taken for cortisol and androgens, c) an oral glucose tolerance test, performed by administering glucose (75 gr), with blood samples taken for glucose and insulin determination. Each woman also underwent a control saline study. We then investigated the relationships between basal and stimulated androgen levels, body weight and fat distribution and fasting and stimulated insulin levels. Although basal cortisol levels were similar, their increase (as AUC) after the ACTH test was higher in women with abdominal obesity than in the other groups. On the contrary, there were no significant differences in basal and stimulated serum levels of dehydroepiandrosterone, androstenedione and 17-hydroxyprogesterone among the three groups. Fasting and stimulated (as AUC) insulin levels were significantly higher (p < 0.05) in women with abdominal obesity than in those with peripheral obesity and controls. No significant correlation was present between basal and stimulated androgen levels and body mass index, the waist-to-hip ratio or basal and stimulated cortisol values. Therefore, our data indicate that adrenal androgen secretion following low-dose ACTH administration in premenopausal women does not seem to be a function of body fat mass, fat distribution and insulin levels, nor does it correlate with the capacity of the adrenal glands to secrete cortisol in both basal and stimulated conditions.
TL;DR: Findings suggest cessation of smoking and weight control for abdominal obesity are important for prevention of CAD among Korean and the detection of low apolipoprotein A1 and high lipoprotein could be useful for Prevention of CAD.
Abstract: Background:Coronary artery diseases (CAD) are increasing in recent years among Korean due to change of socioeconomic status. Even though death rates due to CAD has increased in Korea, few epidemiologic studies have been done about risk factors of CAD. We conducted a case-control study to analyze risk factors for CAD among Korean. Methods:The case series comprised 166 patients with angiographically confirmed CAD, who were admitted to Division of Cardiology in Asan Medical Center. The controls were 137 persons composed of patients with normal coronary arteriogram or patients with normal myocardial SPECT for chest pain. We surveyed life style habits, measured anthropometric variables, and analyzed biochemical markers among CAD patients and controls. Results:In univariate analysis adjusted for age and body mass index (BMI), age, obesity, abdominal obesity, hypertension, low HDL-cholesterol, low apolipoprotein A1, and high lipoprotein (a) were associated with CAD in men and women. Smoking, diabetes, and hypercholesterolemia were associated with in men only. Exercise and high HDL-cholesterol were inversely associated with CAD both in men and women. In multivariate logistic regression analysis, smoking, abdominal obesity, low apolipoprotein A1, and high lipoprotein (a) were found as independent risk factors of CAD among men. Abdominal obesity, low apolipoprotein A1, and high lipoprotein (a) were found as independent risk factors among women. Conclusion:These finding suggest cessation of smoking and weight control for abdominal obesity are important for prevention of CAD among Korean. The detection of low apolipoprotein A1 and high lipoprotein (a) could be useful for prevention of CAD. (Korean Circulation J 1998;28(6):849-862)
TL;DR: It was concluded that this inverse association between UAE and parasympathetic activity in obese women may be an early sign of derangements of endothelial function and autonomic nervous system control, which may contribute to the increased risk of cardiovascular mortality in abdominal obesity.
Abstract: OBJECTIVE: The aim of this work was to examine the relationship between cardiac autonomic function and urinary albumin excretion in obesity. SUBJECTS: These were 27 obese non-diabetic postmenopausal women and 18 non-obese healthy postmenopausal women. MEASUREMENTS: Urinary albumin excretion as well as plasma nitrate, both indices of capillary function, were measured. Power spectral analysis of heart rate variability was performed, as a measurement of vagal function. An oral glucose tolerance test (OGTT) was performed and blood lipids were analysed. RESULTS: The obese women were characterized by higher fasting insulin, sum of glucose, triglycerides and lower high density lipoprotein cholesterol (HDL), the latter of borderline significance, than controls. Urinary albumin excretion (UAE), plasma nitrate and heart rate variability were not different between obese and control women. However, in obese women log UAE correlated positively with systolic and diastolic blood pressure, and inversely with heart rate variability, the latter independent of body mass index (BMI) and the waist/hip circumference ratio. CONCLUSION: It was concluded that this inverse association between UAE and parasympathetic activity in obese women may be an early sign of derangements of endothelial function and autonomic nervous system control, which may contribute to the increased risk of cardiovascular mortality in abdominal obesity.
TL;DR: It is concluded that abdominal obesity is associated with a higher resistance to insulin mediated suppression of non-esterified fatty acids in obese subjects and by glucose/insulin ratio.
Abstract: Triglyceride levels and free fatty acid metabolism are influenced by body fat distribution. To test whether the pattern of fat distribution in obese subjects results in distinct insulin mediated suppression of non-esterified fatty acids which could account for differences in plasma triglycerides, we studied 59 obese subjects who were classified according to waist-to-hip ratio. Non-esterified fatty acids and insulin response to a 75 g oral glucose tolerance test were higher in abdominal obesity. Total non-esterified fatty acids response, after adjustment for sex, showed a positive association with waist-to hip ratio (r = 0.292; p < 0.05). The abdominal obese group had higher fasting triglycerides (1.74+/-0.83 versus 1.11+/-0.71 mmol/L; p = 0.003) and lower glucose/insulin ratio (5.2+/-2.3 versus 7.1+/-2.4; p = 0.003). Stepwise multiple regression analysis showed that triglyceride levels are explained by fasting and 120 min non-esterified fatty acids and by glucose/insulin ratio. We conclude that abdominal obesity is associated with a higher resistance to insulin mediated suppression of non-esterified fatty acids in obese subjects. Variation of triglyceride concentrations in obesity is dependent on both fasting and 120 min non-esterified fatty acids as well as on insulin sensitivity to glucose utilization.