Correspondence between the adult treatment panel III criteria for metabolic syndrome and insulin resistance

Association between visceral adiposity index, lipid accumulation product and type 2 diabetes mellitus in US adults with hypertension: a cross-sectional analysis of NHANES from 2005 to 2018

BACKGROUND

The presence of hypertension significantly increases the risk of diabetes, particularly type 2 diabetes. Recently, Visceral Adiposity Index (VAI) has been introduced as a straightforward and robust alternative indicator for early detection of metabolic syndrome, cardiovascular disease, and T2DM. Visceral adiposity, more dangerous than subcutaneous fat, is associated with metabolic syndrome and cardiovascular diseases. The VAI and Lipid Accumulation Product (LAP) are indices that quantify visceral fat and lipid overaccumulation, respectively. This study aims to explore the association between VAI, LAP, and type 2 diabetes mellitus (T2DM) in US adults with hypertension using NHANES data from 2005 to 2018.

METHODS

We analyzed data from 5,620 participants with hypertension in The National Health and Nutrition Examination Survey (NHANES). VAI and LAP were calculated using established formulas. The VAI is calculated based on a combination of waist circumference, body mass index (BMI), triglycerides, and high-density lipoprotein (HDL) cholesterol levels. Logistic regression models were applied to evaluate the association between these indices and T2DM, adjusting for potential confounders. Subgroup analyses by age and gender were also conducted to assess variations in risk.

RESULTS

In all, 5,620 participants were enrolled in our analysis, with 2,754 (49%) being female, and a mean (standard deviation, SD) age of 57 (15) years. The mean (SD) cumulative average VAI and LAP among all participants was 241 (2.71) and 75 (67), respectively. Totally, higher VAI and LAP indices were significantly associated with an increased risk of T2DM in individuals with hypertension. For VAI, the odds ratios (OR) for T2DM were higher in older adults (≥ 60 years) [95% confidence interval (CI): 1.37, 1.22-1.53, per 1 SD increase] and females [95% confidence interval (CI): 1.39, 1.27-1.52, per 1 SD increase], indicating age and gender differences in risk. Non-linear relationships were observed, suggesting thresholds beyond which the risk of T2DM escalates dramatically.

CONCLUSIONS

Both VAI and LAP are reliable markers for assessing T2DM risk in individuals with hypertension. Incorporating these indices into clinical practice could enhance the identification of high-risk individuals and facilitate early intervention strategies. Future longitudinal studies are needed to confirm these associations and explore targeted interventions.

Metabolic Syndrome and Its Association with Nonalcoholic Steatohepatitis

The relationship between insulin resistance, metabolic syndrome (MetS), and nonalcoholic fatty liver disease (NAFLD) is complicated. Although insulin resistance is almost universal in people with NAFLD and MetS, NAFLD may be present without features of MetS and vice versa. While NAFLD has a strong correlation with cardiometabolic risk factors, these are not intrinsic components of this condition. Taken together, our knowledge gaps call for caution regarding the common assertion that NAFLD is the hepatic manifestation of the MetS, and for defining NAFLD in broad terms as a "metabolic dysfunction" based on a diverse and poorly understood constellation of cardiometabolic features.

The prevalence of metabolic syndrome among Iranian bakers

BACKGROUND

Metabolic syndrome (MetS) is a group of risk factors that are associated with increased risk for atherosclerotic cardiovascular disease.

OBJECTIVE

The objective of this study was to determine the prevalence of metabolic syndrome and its individual components among Iranian bakery workers.

METHODS

A cross-sectional study enrolling 163 randomly selected bakery workers from Semnan province (Northeast Iran), was conducted in 2017. A standard questionnaire was used for data collection. Analyses were performed using t-test, one-way ANOVA and Latent Class Analysis (LCA) in R software.

RESULTS

The prevalence of MetS was 19.8% among bakery workers. More bakery workers with MetS had no regular exercise (p = 0.001) and worked more than eight hours a day (p = 0.001). In this study, the International Diabetes Federation (IDF) diagnostic criteria had more agreement with the American Heart Association (AHA) (49.1%) than the World Health Organization (WHO) and Adult Treatment Panel (ATP) criteria. Also, the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATPIII) had the highest sensitivity for diagnosing MetS. The sensitivity of the four diagnostic methods, WHO, IDF, ATP and AHA, were 45.2%, 61.7%, 67.9% and 64.8%; and their specificity were 98.2%, 100%, 100% and 100%, respectively.

CONCLUSION

The prevalence of MetS is high among bakery workers in Iran. Increased physical activity and intake of fruit and vegetables are recommended for the prevention of MetS.

Evaluating the association of APOA2 polymorphism with insulin resistance in adolescents

Background

265T>C SNP in the APOA-II gene promoter may be associated with obesity risk and insulin resistance (IR). This study aims to analyze the association between the APOA2 − 265T>C SNP and risk for obesity and IR in adolescents.

Material and methods

The study was conducted on 500 adolescents. They were 240 obese and 260 non-obese individuals, aged 16–21 years old. Their mean age was 18.25 ± 2.54 years. Variables examined body weight, height, waist circumference (WC), systolic and diastolic blood pressure (BP), body fat percentage (BF%), and abdominal visceral fat layer. Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) was used as a biomarker for IR. BF% was assessed by body composition analyzer and abdominal visceral fat thickness was determined by ultrasonography. The APOA2 − 265T>C polymorphism genotype was analyzed by PCR amplification of a 273-bp fragment.

Results

Genotype frequencies were in Hardy–Weinberg equilibrium. The frequency of the mutant C allele was significantly higher in obese cases than non-obese cases. After multivariate adjustment, waist, BF%, visceral adipose layer and HOMA-IR were significantly higher in homozygous allele CC carriers than TT + TC carriers. Homozygous individuals for the CC allele had statistically higher values of energy intake, total fat (g/day) and saturated fat (SATFAT) than carriers of the T allele.

Conclusions

Homozygous individuals for the C allele had higher obesity risk than carriers of the T allele and had elevated levels of visceral adipose tissue. Moreover, the present study shows that the CC polymorphism is associated with the development of IR [OR 1.89 (1.35–2.91), P = .012] and remains significant after adjusting for gender, age and body mass index.

Plasma triglyceride/HDL-cholesterol ratio, insulin resistance, and cardiometabolic risk in young adults

Studies in mature adults suggest that the plasma concentration ratio of triglyceride (TG)/HDL-cholesterol (HDL-C) provides a simple way to identify apparently healthy individuals who are insulin resistant (IR) and at increased cardiometabolic risk. This study extends these observations by examining the clinical utility of the TG/HDL-C ratio and the metabolic syndrome (MetS) in 2,244 healthy college students (17-24 years old) of Mexican Mestizo ancestry. The TG/HDL-C ratio separating the 25% with the highest value was used to identify IR and increased cardiometabolic risk. Cardiometabolic risk factors were more adverse in men and women whose TG/HDL-C ratios exceeded 3.5 and 2.5, respectively, and approximately one third were identified as being IR. The MetS identified fewer individuals as being IR, but their risk profile was accentuated. In conclusion, both a higher TG/HDL-C ratio and a diagnosis of the MetS identify young IR individuals with an increased cardiometabolic risk profile. The TG/HDL-C ratio identified a somewhat greater number of "high risk" subjects, whereas the MetS found a group whose risk profile was somewhat magnified. These findings suggest that the TG/HDL-C ratio may serve as a simple and clinically useful approach to identify apparently healthy, young individuals who are IR and at increased cardiometabolic risk.

Comparison of the abilities of the plasma triglyceride/high-density lipoprotein cholesterol ratio and the metabolic syndrome to identify insulin resistance

This study compares the ability of an elevated triglyceride/high-density lipoprotein cholesterol (TG/HDL-C) ratio, using sex-specific cut-points, to identify insulin-resistant individuals within a population without known cardiac disease or diabetes with that obtained using the diagnostic criteria of the metabolic syndrome (MetS). Measurements were made of waist circumference (WC), systolic and diastolic blood pressure, fasting plasma glucose, fasting plasma insulin (FPI), plasma TG and plasma HDL-C concentrations in 1102 women and 464 men. These data were used to classify subjects as being insulin resistant (FPI concentration in the upper quartile) and having the MetS or an elevated TG/HDL-C ratio (>2.5 and >3.5 for women and men, respectively). The sensitivity and specificity with which the two indices identified insulin-resistant subjects were similar (43% and 81% for TG/HDL-C ratio and 45% and 82% for MetS), as the number of individuals was found with either an elevated TG/HDL-C ratio (n = 386) or the MetS (n = 384). Eighty-one per cent of the individuals were identified concordantly. Cardio-metabolic risk profiles in 'low-risk' individuals identified by a low TG/HDL-C ratio were comparable to those who did not have the MetS, and this was also the case when comparing 'high-risk' groups identified by having the MetS or an elevated TG/HDL-C ratio. These findings suggest that TG/HDL-C concentration ratio is as adequate as MetS diagnosis to identify insulin-resistant subjects.

[Metabolic syndrome and insulin resistance in patients with prostate cancer treated with androgen deprivation hormone]

INTRODUCTION AND OBJECTIVES

Androgen suppression in prostate cancer is responsible for many side effects. Many studies, mostly retrospective, have found an association between androgen deprivation and increased cardiovascular morbidity. If the cardiovascular impact was chosen, an etiological explanation would be the occurrence of metabolic disorders, particularly insulin resistance. The objective of our work was to conduct a review of the literature assessing the impact of androgen deprivation on the onset of insulin resistance, the metabolic syndrome and changes in key markers of insulin resistance.

MATERIALS AND METHODS

A systematic review of literature from the Pubmed database search was performed using the following keywords: androgen deprivation therapy, metabolic syndrome, insulin resistance, hyperglycemia, cardiovascular diseases, cardiovascular risk, abdominal obesity.

RESULTS

Twelve studies were included, bringing into focus a 55% prevalence of metabolic syndrome in patients treated for more than 12 months, an increase in fat mass and decreased lean body mass, an increase in abdominal subcutaneous fat and in visceral adiposity. The insulin was increased in four studies (25 to 60% three months dice). The increased insulin resistance was assessed by the Homeostasis Model Assessment (HOMA) was postponed three times (12% in two prospective cohort studies of type). The increase in triglycerides (20 to 40% at 12 months) and total cholesterol (7 to 11%) was observed in five studies, and increased LDL cholesterol and HDL in three studies (9 to 22%).

CONCLUSION

All studies of this analysis appeared to converge towards the development of insulin resistance and metabolic disorders, however, no prospective cohort study of good methodological quality were identified. It would be necessary to conduct a prospective multicenter study in order to have a causal quality.

Relation among the plasma triglyceride/high-density lipoprotein cholesterol concentration ratio, insulin resistance, and associated cardio-metabolic risk factors in men and women

Results of recent studies using the ratio of plasma triglyceride (TG) to high-density lipoprotein (HDL) cholesterol concentration to identify insulin-resistant patients at increased cardiometabolic risk have emphasized that the cut point used for this purpose will vary with race. Because TG and HDL cholesterol concentrations vary with gender, this analysis was initiated to define gender-specific plasma TG/HDL cholesterol concentration ratios that best identified high-risk subjects among women (n = 1,102) and men (n = 464) of primarily European ancestry. Insulin resistance was defined as the 25% of the population with the highest values for fasting plasma insulin concentration and homeostasis model assessment of insulin resistance. Using TG/HDL concentration ratios >2.5 in women and >3.5 in men identified subgroups of men and women that were comparable in terms of insulin resistance and associated cardiometabolic risk, with significantly higher values for fasting plasma insulin, homeostasis model assessment of insulin resistance, blood pressure, body mass index, waist circumference, and glucose and TG concentrations and lower HDL cholesterol concentrations than in women and men below these cut points. The sensitivity and specificity of these gender-specific cut points to identify insulin-resistant subjects were about 40% and about 80%, respectively. In conclusion, the plasma TG/HDL cholesterol concentration ratio that identifies patients who are insulin resistant and at significantly greater cardiometabolic risk varies between men and women.

CYP19 gene expression in subcutaneous adipose tissue is associated with blood pressure in women with polycystic ovary syndrome

In polycystic ovary syndrome (PCOS), hypertension has been linked to androgen excess and insulin resistance. Aromatase, an enzyme encoded by the CYP19 gene, affects androgen metabolism and estrogen synthesis, influencing the androgen to estrogen balance. We characterized CYP19 gene expression in subcutaneous adipose tissue of women with PCOS and normal controls and evaluated the association between subcutaneous fat CYP19 mRNA, circulating hormone levels, and blood pressure. This case-control study was carried out with 31 PCOS patients and 27 BMI-matched normotensive non-hirsute women with regular cycles. Participants underwent anthropometric measurements, collection of blood samples, and adipose tissue biopsy (28 PCOS and 19 controls). Hypertension was defined as systolic blood pressure ≥ 130 mmHg and/or diastolic blood pressure ≥ 85 mmHg. PCOS patients were divided into normotensive and hypertensive. Main outcome measures were serum estrogen and androgen levels, estrogen-to-androgen ratio, and CYP19 gene expression in subcutaneous fat. Subcutaneous CYP19 mRNA was higher in hypertensive PCOS than in control and normotensive PCOS women (p = 0.014). Estrogen-to-androgen ratio was lower in hypertensive PCOS than controls (p < 0.003). Estrogen-to-androgen ratio ≤ 0.06 (median for the three groups) was observed in 91% of hypertensive PCOS women, vs. 37% and 61% in the control and normotensive PCOS groups (p = 0.011). CYP19 gene expression in subcutaneous fat of PCOS patient correlated positively with systolic (p = 0.006) and diastolic blood pressure (p = 0.009). Androgen excess and hyperinsulinemia may play a role in the molecular mechanisms that activate aromatase mRNA transcription in abdominal fat tissue.

Optimal uric acid threshold to identify insulin resistance in healthy women

BACKGROUND

Identifying insulin-resistant (IR) individuals is an issue of particular interest in the assessment of cardiometabolic risk, but there is no simple way to accomplish this task. Our aims were to determine the relationship between uric acid and insulin resistance and to define the optimal uric acid cutoff to identify insulin resistance in women.

METHODS

A population-based sample of 588 women without cardiovascular diseases, diabetes, or low glomerular filtration rate (GFR) was divided according to uric acid tertiles. Systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting glucose, low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), TG/HDL-C ratio, insulin [fasting plasma insulin (FPI)], and homeostasis model assessment of insulin resistance (HOMA-IR) were compared between the mentioned tertiles. Receiver operating characteristic (ROC) curves were constructed to determinate the optimal cutoff of uric acid and identify IR individuals defined by the top tertile of FPI and HOMA-IR. The same variables were compared using the top tertile of uric acid and the maximum Youden index as cutoffs. The P values were adjusted by age, GFR, and body mass index (BMI) using analysis of covariance (ANCOVA).

RESULTS

FPI, HOMA-IR, and all of the cardiometabolic risk factors increased through uric acid tertiles. Both cutoffs of uric acid, estimated by the top tertile and by ROC, were identical (4.0 mg/dL). FPI, HOMA-IR, SBP, DBP, TG, TG/HDL-C ratio, and fasting glucose were higher, whereas HDL-C was lower in women who had uric acid levels >4.0 mg/dL. All of the differences remained significant after the adjustment by age and GFR.

CONCLUSION

In healthy women, uric acid levels >4.0 mg/dL were associated with all the markers of IR.

Metabolic syndrome in subjects at high risk for type 2 diabetes: the genetic, physiopathology and evolution of type 2 diabetes (GENFIEV) study

BACKGROUND AND AIM

We evaluated the relationship between insulin resistance (IR) and insulin secretion with the metabolic syndrome (MS) in 885 subjects (377 men/508 women, age 49±11 years, BMI 29±5.2kgm(-2)) at risk of diabetes enrolled in the genetics, pathophysiology and evolution of type 2 diabetes (GENFIEV) study.

METHODS AND RESULTS

All subjects underwent a 75-g oral glucose tolerance test (OGTT) for the estimation of plasma levels of glucose and C-peptide, as well as fasting insulin and lipid profile. IR was arbitrarily defined as HOMA-IR value above the 75th centile of normal glucose tolerance (NGT) subjects. Overall MS prevalence (National Cholesterol Treatment Panel-Adult Treatment Panel (NCEP-ATPIII) criteria) was 33%, 19% in subjects with NGT, 42% in impaired fasting glucose (IFG), 34% in impaired glucose tolerance (IGT), 74% in IFG+IGT subjects, and 56% in newly diagnosed diabetic patients. Prevalence was slightly higher with IDF criteria. MS prevalence was >50% in subjects with 2h glucose >7.8mmoll(-1), independently of fasting plasma glucose. IR prevalence was higher in subjects with MS than in those without (63% vs. 23%; p<0.0001) and increased from 54% to 73% and 88% in the presence of three, four or five traits, respectively. IR occurred in 42% of subjects with non-diabetic alterations of glucose homeostasis, being the highest in those with IFG+IGT (IFG+IGT 53%, IFG 45%, IGT 38%; p<0.0001). Individuals with MS were more IR irrespective of glucose tolerance (p<0.0001) with no difference in insulinogenic index. Hypertriglyceridaemia (OR: 3.38; Confidence Interval, CI: 2.294.99), abdominal obesity (3.26; CI: 2.18-4.89), hyperglycaemia (3.02; CI: 1.80-5.07) and hypertension (1.69; CI: 1.12-2.55) were all associated with IR.

CONCLUSIONS

These results show that in subjects with altered glucose tolerance (in particular IFG+IGT) MS prevalence is high and is generally associated to IR. Some combinations of traits of MS may significantly contribute to identify subjects with IR.

Relationships among insulin resistance, obesity, diagnosis of the metabolic syndrome and cardio-metabolic risk

The aim of this study is to test the hypotheses that: 1) diagnosing the metabolic syndrome does not effectively identify insulin-resistant (IR) individuals; and 2) waist circumference (WC) is no better than body mass index (BMI) in predicting insulin resistance or the components of the metabolic syndrome (MetS). Measurements of BMI, WC, blood pressure, and fasting plasma glucose, insulin (FPI), triglycerides (TG), and HDL-cholesterol (HDL-C) concentrations were made in 1,300 adults, without known cardiovascular disease (CVD) or drug treatment of hypertension or diabetes. Receiver operating characteristic curves were used to determine the ability of the MetS, and its components, to identify IR individuals. In addition, comparisons were made of CVD risk factors following division of the population into quartiles of FPI concentrations, and univariate and multiple regression analysis used to compare the ability of WC, BMI, and FPI as predictors of MetS components. The MetS was no more effective in identifying IR individuals than several individual components (sensitivity~40%), and IR individuals not identified were at significantly increased CVD risk. FPI concentration was the best predictor of an abnormal glucose, TG, and HDL-C, whereas the adiposity indices were better predictors of abnormal blood pressure. The relationship between BMI and WC with the MetS and its components seemed comparable.

Identification of cardiometabolic risk among collegiate football players

CONTEXT

Excessive fat mass clearly has adverse effects on metabolic processes that can ultimately lead to the development of chronic disease. Early identification of high-risk status may facilitate referral for definitive diagnostic tests and implementation of interventions to reduce cardiometabolic risk.

OBJECTIVE

To document the prevalence of metabolic syndrome among collegiate football players and to develop a clinical prediction rule that does not require blood analysis to identify players who may possess a high level of cardiometabolic risk.

DESIGN

Cross-sectional cohort study.

SETTING

University athletic training research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Sixty-two National Collegiate Athletic Association Division I Football Championship Subdivision football players (age = 19.9 +/- 1.2 years, height = 182.6 +/- 6.1 cm, mass = 97.4 +/- 18.3 kg).

MAIN OUTCOME MEASURE(S)

Anthropometric characteristics associated with body fat, isokinetic quadriceps strength, and biometric indicators associated with metabolic syndrome were measured. Participants were classified as high risk or low risk for future development of type 2 diabetes and cardiovascular disease.

RESULTS

The prevalence of metabolic syndrome in the cohort was 19% (12 of 62), and 79% (49 of 62) of the players exceeded the threshold for 1 or more of its 5 components. A 4-factor clinical prediction rule that classified individuals on the basis of waist circumference, blood pressure, quadriceps strength, and ethnic category had 92% sensitivity (95% confidence interval = 65%, 99%) and 76% specificity (95% confidence interval = 63%, 86%) for discrimination of high-risk or low-risk status.

CONCLUSIONS

The risk for developing type 2 diabetes and cardiovascular disease appears to be exceptionally high among collegiate football players. A lack of race-specific criteria for the diagnosis of metabolic syndrome almost certainly contributes to an underestimation of the true level of cardiometabolic risk for African American collegiate football players.

Evidence on the applicability of the ATPIII, IDF and CDS metabolic syndrome diagnostic criteria to identify CVD and T2DM in the Chinese population from a 6.3-year cohort study in mid-eastern China

AIMS

This study evaluates the effectiveness of three metabolic syndrome (MS) criteria in identifying cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM) in the Chinese population.

METHODS

3598 subjects were recruited from a cohort study on Prevention of Multiple Metabolic disorders and MS in Jiangsu of China (PMMJS), followed at 6.3 years. MS was diagnosed using criteria of the National Cholesterol Education Program's Adult Treatment Panel III (ATPIII), the International Diabetes Federation (IDF) and Chinese Diabetes Society (CDS). Cox regression model was used to analysis the association between MS and onset of CVD and T2DM. Receiver operating characteristic (ROC) curve, sensitivity and specificity were also used to test the ability of three MS criteria to identify CVD or T2DM.

RESULTS

Among three criteria, CDS has the highest specificity but lowest sensitivity. Using the CDS criterion, over 50 percent of patients would be misdiagnosed. ATPIII criterion has the shortest distance in ROC curve, lowest false positive rate and false negative rate for identifying CVD and T2DM. ATPIII+/IDF+ has lower ability to predict CVD than ATPIII+/IDF-. ATPIII+/IDF+ and ATPIII+/IDF- has similar ability to predict T2DM.

CONCLUSIONS

The ATPIII-MS criterion has the highest ability to predict CVD and T2DM. ATPIII is the best MS criterion for the Chinese population.

Optimal cut-off of homeostasis model assessment of insulin resistance (HOMA-IR) for the diagnosis of metabolic syndrome: third national surveillance of risk factors of non-communicable diseases in Iran (SuRFNCD-2007)

Aim

We have recently determined the optimal cut-off of the homeostatic model assessment of insulin resistance for the diagnosis of insulin resistance (IR) and metabolic syndrome (MetS) in non-diabetic residents of Tehran, the capital of Iran. The aim of the present study is to establish the optimal cut-off at the national level in the Iranian population with and without diabetes.

Methods

Data of the third National Surveillance of Risk Factors of Non-Communicable Diseases, available for 3,071 adult Iranian individuals aging 25-64 years were analyzed. MetS was defined according to the Adult Treatment Panel III (ATPIII) and International Diabetes Federation (IDF) criteria. HOMA-IR cut-offs from the 50th to the 95th percentile were calculated and sensitivity, specificity, and positive likelihood ratio for MetS diagnosis were determined. The receiver operating characteristic (ROC) curves of HOMA-IR for MetS diagnosis were depicted, and the optimal cut-offs were determined by two different methods: Youden index, and the shortest distance from the top left corner of the curve.

Results

The area under the curve (AUC) (95%CI) was 0.650 (0.631-0.670) for IDF-defined MetS and 0.683 (0.664-0.703) with the ATPIII definition. The optimal HOMA-IR cut-off for the diagnosis of IDF- and ATPIII-defined MetS in non-diabetic individuals was 1.775 (sensitivity: 57.3%, specificity: 65.3%, with ATPIII; sensitivity: 55.9%, specificity: 64.7%, with IDF). The optimal cut-offs in diabetic individuals were 3.875 (sensitivity: 49.7%, specificity: 69.6%) and 4.325 (sensitivity: 45.4%, specificity: 69.0%) for ATPIII- and IDF-defined MetS, respectively.

Conclusion

We determined the optimal HOMA-IR cut-off points for the diagnosis of MetS in the Iranian population with and without diabetes.

Epidemiological Investigation of Metabolic Syndrome and Analysis of Relevant Factors in North-Eastern China

This epidemiological study was conducted to investigate the prevalence of metabolic syndrome and associated risk factors in Chinese subjects from Dehui in northeastern China. Using a random sampling method, a questionnaire was completed by 3785 permanent residents aged 18-72 years and relevant clinical data were collected from each subject. Binary multivariate logistic regression analysis was used to identify factors that were significantly associated with metabolic syndrome. Based on the International Diabetes Federation definition, the prevalence of metabolic syndrome was 22.4%, which is higher than that of the general Chinese population. Metabolic syndrome occurred more frequently in females and the prevalence gradually increased with age. Living in an urban setting and being female, > 50 years old, overweight, having total cholesterol ≥ 5.18 mmol/l, low-density lipoprotein cholesterol ≥ 3.1 mmol/l, and a fatty liver were significant risk factors associated with metabolic syndrome.

Endothelial dysfunction in metabolic syndrome: prevalence, pathogenesis and management

The metabolic syndrome (MetS) is characterized by the presence of central obesity, impaired glucose metabolism, dyslipidemia and hypertension. Several studies showed that MetS is associated with increased risk for type 2 diabetes mellitus (T2DM) and vascular events. All components of MetS have adverse effects on the endothelium. Endothelial dysfunction plays a role in the pathogenesis of atherosclerosis and might also increase the risk for insulin resistance and T2DM. We review the prevalence and pathogenesis of endothelial dysfunction in MetS. We also discuss the potential effects of lifestyle measures and pharmacological interventions on endothelial function in these patients. It remains to be established whether improving endothelial function in MetS will reduce the risk for T2DM and vascular events.

Optimal threshold of homeostasis model assessment for insulin resistance in an Iranian population: the implication of metabolic syndrome to detect insulin resistance

We assessed the threshold of homeostasis model assessment (HOMA) values to determine insulin resistance (IR) in a sample of Iranians and examined the associations of IR with metabolic syndrome (MetS). Study comprised 1327 non-diabetic and non-hypertensive subjects (438 men, 838 women; aged 20-77 years) incurred in four different locations (Tehran, Iran), 2005-2008. Lower limit of the top quintile of HOMA values in subjects without any metabolic abnormality was considered as the threshold of IR. This threshold was 1.8 (1.7 men; 1.8 women). Overall, 41.1% (36.3% men; 41.5% women) of subjects had IR. HOMA cut-off to determine MetS was 1.95 for ATPIII definition, and 1.85 for IDF. IR associated MetS (ATPIII: odds ratio (OR)=2.9, 95% CI=2.2-3.9, p<0.05; IDF: OR=2.94, 95% CI: 2.3-3.8, p<0.05). Sensitivity of MetS to detect IR was 22.4% for IDF and 36.2% for ATPIII criteria. In multivariate models, HOMA was predicted by waist circumference, and inversely by age and serum HDL-cholesterol. In this study, the cut point of HOMA to detect IR was lower than other populations. IR is an unyielding correlate of MetS; but definitions of MetS are insensitive measures of IR in our population.

From the metabolic syndrome to the concept of global cardiometabolic risk

Although the clustering of cardiovascular risk factors is unquestionable, the clinical significance of the metabolic syndrome as a distinct entity has been debated in the past years. Recently, the term ‘metabolic syndrome’ has been replaced by ‘global cardiometabolic risk’ which implies cardiovascular risk factors beyond the metabolic syndrome. The metabolic syndrome can be frequently detected among people in western and developing countries affecting 25-30% of adult population, and its prevalence rate is increasing. Prospective studies show that the metabolic syndrome is a significant predictor of incident diabetes but has a weaker association with cardiovascular morbidity and mortality. At the same time the metabolic syndrome is inferior to established predicting models for either type 2 diabetes or cardiovascular disease.The underlying pathomechanism of the metabolic syndrome is still poorly understood. The role of insulin resistance – although not as a single factor – is still considered as a key component. In the last decade the importance of abdominal obesity has received increased attention but some studies, mainly in the Asian population, showed that central obesity is not an essential component of the syndrome. Regardless of the theoretical debates the practical implications are indisputable. The frequent clustering of hypertension, dyslipidaemia and glucose intolerance, that often accompanies central obesity, can not be ignored. Following the detection of one risk factor, the presence of other, traditional and non-traditional factors should be searched for, as the beneficial effect of intensive, target oriented, continuous treatment of metabolic and cardiovascular risk factors has been proven in both the short and long term.

Use of confirmatory factor analysis for the identification of new components of the metabolic syndrome: the role of plasminogen activator inhibitor-1 and Haemoglobin A1c

BACKGROUND AND AIM

This study was aimed to identify additional components of metabolic syndrome from a set of cardiovascular risk markers.

METHODS AND RESULTS

The homeostasis model assessment of insulin resistance (HOMA-IR), C-reactive protein, fibrinogen, plasminogen activator inhibitor-1 (PAI-1), von Willebrand factor, homocysteine, Haemoglobin A1c (HbA1c), and lipoprotein(a) were assessed in a population-based sample of 902 nondiabetic adult subjects. Those biomarkers that were associated with metabolic syndrome were evaluated by multiple regression analysis, along with other traditional cardiovascular risk factors. Confirmatory factor analysis (CFA) was used to test the hypothesis that both the established components of metabolic syndrome and the novel variables identified by the regression analysis were associated with a single underlying factor. HOMA-IR, PAI-1 and HbA1c were the only biomarkers independently related to metabolic syndrome. CFA validated a one-factor model that included these variables. Moreover, the indices of goodness of fit were better for this expanded model than those obtained for a previously validated one-factor model that was restricted to the conventional elements of the syndrome.

CONCLUSIONS

These findings show that PAI-1 and HbA1c are singularly linked to metabolic syndrome. Their elevation is presumably another manifestation of the same pathophysiological mechanism that underlies the recognized traits of the syndrome.

Comparative performance of three metabolic syndrome definitions in the prediction of acute coronary syndrome

OBJECTIVE

The value of the recently introduced definitions of metabolic syndrome (MetS) in the identification of high cardiovascular risk subjects remains questionable. We examined the association among different definitions of MetS, and the occurrence of a first-ever acute coronary syndrome (ACS).

METHODS

We studied 211 patients with a first-ever ACS and 210 control subjects. We recorded cardiovascular risk factors and the presence of MetS using 3 different definitions, according to the National Cholesterol Education Program Adult Treatment Panel (NCEP-ATP) III, National Heart, Lung and Blood Institute/American Heart Association (NHLBI/AHA), and International Diabetes Federation (IDF), respectively. The association of MetS with ACS was assessed using univariate and multivariate logistic regression models after adjusting for potential confounding factors, such as gender, age, body mass index, hypertension, diabetes mellitus, and lipids.

RESULTS

ACS cases had a prevalence of metabolic syndrome according to NCEP-ATP III, NHLBI/AHA, and IDF criteria of 72.5%, 81.2%, and 79.1%, respectively. The unadjusted odds ratio (OR) for a first-ever ACS were 2.32 (95% CI: 1.53-3.52, p=0.001), 2.82 (95% CI: 1.79-4.43, p=0.001), and 3.26 (95% CI: 2.12-5.00, p=0.001) for NCEP-ATP III, NHLBI/AHA, and IDF MetS definitions, respectively. Multivariate analyses revealed that only IDF-defined MetS was significantly associated with ACS (OR: 2.23 95% CI: 1.30-3.82, p=0.003), while of the MetS components only waist circumference remained independently associated with ACS (O.R: 1.045 95% CI: 1.014-1.078, p=0.005).

CONCLUSION

The definition of MetS according to the IDF criteria appears to be a better predictor of ACS than NCEP-ATP III and NHLBI/AHA.

Community-based study on summer-winter difference in insulin resistance in Kin-Chen, Kinmen, Taiwan

BACKGROUND

The aim of this community-based study was to explore the summer-winter difference in insulin resistance in Kin-Chen, Kinmen.

METHODS

A total of 2,412 residents aged 40 and over was enrolled in a mass survey in Kin-Chen, Kinmen, by the Yang-Ming Crusade, a volunteer organization of well-trained medical students from National Yang-Ming University. All participants were investigated in winter (first phase, January and February, before Chinese New Year) and summer (secondary phase, July and August) in 2002. Structured questionnaires, demographic and physical data, lifestyle, and blood chemistry parameters were collected.

RESULTS

Higher levels of fasting insulin, HOMA-insulin resistance and triglycerides, but lower levels of high-density lipoprotein cholesterol were found in summer than in winter. The prevalence of metabolic syndrome was higher in summer than in winter, with differences of 7.7% in both genders (p = 0.0092 in men, p = 0.0037 in women). Body mass index (BMI), age and physical activity were significantly correlated with metabolic syndrome. After controlling for BMI and other risk profiles, summer was independently and positively associated with fasting insulin and insulin resistance regardless of metabolic syndrome.

CONCLUSION

Fasting insulin, insulin resistance and prevalence of metabolic syndrome were higher in summer than in winter. BMI and season were 2 major determinants of the variation in fasting insulin. The contextual impacts of seasonal variation in shaping metabolic syndrome or insulin resistance in populations need to be reemphasized.

Insulin resistance, serum adiponectin, and proinflammatory markers in young subjects with the metabolic syndrome

Insulin resistance is the underlying metabolic abnormality in the metabolic syndrome. The low-grade chronic inflammation may be associated with metabolic risk factors and atherogenesis. The aim of our study was to establish the link between the metabolic syndrome, as defined by the National Cholesterol Education Program (NCEP) criteria, and insulin sensitivity, serum adiponectin, and parameters of chronic inflammation in young subjects. The group of 223 subjects (mean age, 25.86 +/- 5.49 years; body mass index, 28.04 +/- 6.91 kg/m2) was studied. Oral glucose tolerance test, euglycemic hyperinsulinemic clamp, and estimation of serum adiponectin and proinflammatory factors were performed. The NCEP-defined metabolic syndrome was present in 49 subjects (21.97%). The higher the number of NCEP criteria fulfilled was, the bigger were the decrease in insulin sensitivity (P < .0001) and adiponectin (P < .0001) and the increase in fasting and postload insulin (both Ps < .0001), C-reactive protein (P < .0001), interleukin 18 (P < .0001), interleukin 6 (P < .0001), and soluble tumor necrosis factor-alpha receptors sTNFR1 (P < .0001) and sTNFR2 (P < .0001) observed. Multiple regression analysis revealed that adiponectin and inflammatory factors predicted NCEP score independent of insulin sensitivity (all adjusted beta values between .16 and .32, all Ps < .01). Young subjects with metabolic syndrome demonstrate an increased inflammatory response and lower adiponectin concentration.

Diagnosis of insulin resistance in hypertensive patients by the metabolic syndrome: AHA vs. IDF definitions

BACKGROUND

Subjects with the metabolic syndrome are accompanied by insulin resistance (IR). However, it is not clear how well the newly defined metabolic syndrome identifies IR specifically in hypertensive subjects.

AIMS

The purpose of the study was to evaluate the performance of the metabolic syndrome, defined by the American Heart Association (AHA) and the International Diabetes Federation (IDF) definitions, in identifying IR in hypertension.

METHODS

The analysis is a cross-sectional study. Totally, 228 hypertensive patients and 92 non-diabetic normotensive controls who received insulin suppressive tests for direct evaluation of their insulin sensitivity were included from the Stanford Asia and Pacific Program for Hypertension and IR. McNemar's tests were used to compare sensitivity and specificity of the AHA-defined with the IDF-defined metabolic syndrome in diagnosis of IR.

RESULTS

The sensitivity of the metabolic syndrome for IR in hypertension was 89.7% and the specificity 45.9% by the AHA definition. Using the IDF definition, the sensitivity was 77.6%, and the specificity increased to 63.5%. The diagnostic power of individual components of the syndrome was also modest. The predictive discrimination of wider waist circumference was similar to that of the AHA-defined metabolic syndrome.

CONCLUSIONS

Use of the metabolic syndrome by the AHA definition provided good sensitivity, but low specificity to diagnose IR in hypertension. The IDF definition improved in false-positive rate, but it was still not specific enough to identify IR in hypertension.

Evaluation of metabolic syndrome in adults of Talca city, Chile

OBJECTIVE

Insulin resistance (IR) is an important risk factor for type 2 Diabetes Mellitus (DM2) and cardiovascular disease (CVD). Metabolic Syndrome (MS) is a clustering of metabolic alterations associated to IR; however, there is no international consensus for defining its diagnosis. Our objective was to evaluate the prevalence and characteristics of MS identified by the ATP III and IDF criteria in adults from Talca city.

RESEARCH AND METHODS

We studied 1007 individuals, aged 18-74, and residents from Talca. MS subjects were defined according to ATP III (three altered factors) and IDF criteria (patients with waist circumference >80/90 cm (W/M) and two others altered factors).

RESULTS

The prevalence of metabolic syndrome according to the IDF and ATP III criteria was 36.4% and 29.5%, respectively after adjustment for age and sex. The agreement for both criteria was 89%. The prevalence in men was higher than in women for both MS definitions, although not significant. MS probability increased with age, and the highest risk was in the 57-68 age group (ATP-MS) and 53-72 age group (IDF-MS). Hypertension, high triglycerides and abdominal obesity are the most frequent alterations in MS.

CONCLUSION

MS prevalence in adults was higher when diagnosed with IDF than with ATP criterion; in both, age is directly related with the MS presence. The MS subjects showed higher levels of blood pressure, waist circumference and plasma triglycerides. Considering our results, it is worrisome that one third of our population has a high risk of developing DM2 and CVD in the future.

Waist circumference, not the metabolic syndrome, predicts glucose deterioration in type 2 diabetes

We sought to assess the relationship between the metabolic syndrome, abdominal obesity, and glucose deterioration amongst patients with type 2 diabetes. Our prospective cohort consisted of 164 adult patients with established diabetes who have a history of poor glycemic control, have just completed an intensive intervention aimed at improved control, and have demonstrated reduced HbA1c prior to enrollment. Waist circumference and presence of metabolic syndrome were assessed at baseline, and patients were followed up (median 24 months) for assessment of the study outcome, namely, time-to-hyperglycemic relapse, predefined as HbA1c >8% and >1% rise over baseline. Kaplan-Meier estimates of relapse-free glucose maintenance and multivariable Cox regression models were used for quantifying the independent effects of the metabolic syndrome and waist circumference on risk of glucose deterioration. The mean baseline waist circumference was 42.9 5.5 inches. Prevalence of the metabolic syndrome was 80%. During follow-up, 39 patients (24%) experienced hyperglycemic relapse. The metabolic syndrome was not associated with time-to-relapse (P = 0.15). The waist circumference component by itself, however, was associated with increased likelihood of hyperglycemic relapse with an unadjusted hazard ratio of 3.4 (95% confidence interval (CI) 1.2-9.7) and a hazard ratio of 3.2 (95% CI 1.1-9.1) after adjusting for age, gender, insulin use, weight change, and physical activity level. The National Cholesterol Education Program Adult Treatment Panel III (NCEP ATPIII) metabolic syndrome had limited ability to predict glucose deterioration in this type 2 diabetes cohort. Waist circumference by itself, however, is a strong predictor of future glucose control, and may be a parsimonious tool for risk stratification. BMI may also be a useful predictive tool.

Visceral obesity as a risk factor for colorectal neoplasm

BACKGROUND AND AIM

Obesity as a risk factor for colorectal neoplasm (CRN) is controversial. In the present study, we evaluated visceral obesity as a risk factor for CRN.

METHODS

We prospectively enrolled 200 consecutive, asymptomatic adults (male : female = 133:67, mean age, 50.9 +/- 8.5 years) undergoing both colonoscopy and abdominopelvic computed tomography (CT) scan for routine health evaluations. The presence or absence and the characteristics of CRN were determined during colonoscopy. The amount of visceral adipose tissue (VAT) and subcutaneous adipose tissue was measured by an abdominopelvic CT scan. Body mass index, waist circumference, and percentage of body fat were measured. Blood pressure and other blood markers for assessing the metabolic syndrome were also investigated.

RESULTS

Of the 200 patients, 53 (26.5%) had CRN. Old age, smoking, metabolic syndrome, and a high fasting plasma glucose level were associated with an increased risk of CRN. VAT (P < 0.01) and waist circumference (P = 0.01) were significantly higher in those with CRN. A multivariate analysis of the risks of CRN showed an odds ratio of 4.07 (95% confidence interval: 1.01-16.43, P = 0.03) for those with VAT over 136.61 cm(2) relative to those with VAT under 67.23 cm(2). Waist circumference, metabolic syndrome, and fasting plasma glucose levels were not independent risk factors for CRN in the multivariate analysis.

CONCLUSION

Increased VAT is an independent risk factor for CRN. Further large scale studies are needed to clarify the causal relationship between VAT and CRN.

1H NMR metabonomics approach to the disease continuum of diabetic complications and premature death

Subtle metabolic changes precede and accompany chronic vascular complications, which are the primary causes of premature death in diabetes. To obtain a multimetabolite characterization of these high-risk individuals, we measured proton nuclear magnetic resonance (1H NMR) data from the serum of 613 patients with type I diabetes and a diverse spread of complications. We developed a new metabonomics framework to visualize and interpret the data and to link the metabolic profiles to the underlying diagnostic and biochemical variables. Our results indicate complex interactions between diabetic kidney disease, insulin resistance and the metabolic syndrome. We illustrate how a single 1H NMR protocol is able to identify the polydiagnostic metabolite manifold of type I diabetes and how its alterations translate to clinical phenotypes, clustering of micro- and macrovascular complications, and mortality during several years of follow-up. This work demonstrates the diffuse nature of complex vascular diseases and the limitations of single diagnostic biomarkers. However, it also promises cost-effective solutions through high-throughput analytics and advanced computational methods, as applied here in a case that is representative of the real clinical situation.

Analysis of agreement among definitions of metabolic syndrome in nondiabetic Turkish adults: a methodological study

BACKGROUND

We aimed to explore the agreement among World Health Organization (WHO), European Group for the Study of Insulin Resistance (EGIR), National Cholesterol Education Program (NCEP), American College of Endocrinology (ACE), and International Diabetes Federation (IDF) definitions of the metabolic syndrome.

METHODS

1568 subjects (532 men, 1036 women, mean age 45 and standard deviation (SD) 13 years) were evaluated in this cross-sectional, methodological study. Cardiometabolic risk factors were determined. Insulin sensitivity was calculated by HOMA-IR. Agreement among definitions was determined by the kappa statistic. ANOVA and post hoc Tukey's test were used to compare multiple groups.

RESULTS

The agreement between WHO and EGIR definitions was very good (kappa: 0.83). The agreement between NCEP, ACE, and IDF definitions was substantial to very good (kappa: 0.77-0.84). The agreement between NCEP or ACE or IDF and WHO or EGIR definitions was fair (kappa: 0.32-0.37). The age and sex adjusted prevalence of metabolic syndrome was 38% by NCEP, 42% by ACE and IDF, 20% by EGIR and 19% by WHO definition. The evaluated definitions were dichotomized after analysis of design, agreement and prevalence: insulin measurement requiring definitions (WHO and EGIR) and definitions not requiring insulin measurement (NCEP, ACE, IDF). One definition was selected from each set for comparison. WHO-defined subjects were more insulin resistant than subjects without the metabolic syndrome (mean and SD for log HOMA-IR, 0.53 +/- 0.14 vs. 0.07 +/- 0.23, respectively, p < 0.05) and had higher Framingham risk scores (mean and SD, 2.99 +/- 4.64% vs. 1.10 +/- 1.87%, respectively, p < 0.05). The additional subjects identified by IDF definition, but not by WHO definition also had more insulin resistance and higher Framingham risk scores than subjects without the metabolic syndrome (mean and SD, log HOMA-IR 0.18 +/- 0.18 vs. 0.07 +/- 0.23, p < 0.05 and Framingham risk score 2.93 +/- 4.54% vs. 1.10 +/- 1.87%, p < 0.05). The IDF-identified additional subjects had similar Framingham risk scores as WHO-identified subjects (p > 0.05), but lower log HOMA-IR values (p < 0.05).

CONCLUSION

The metabolic syndrome definitions that do not require measurement of insulin levels (NCEP, ACE and IDF) identify twice more patients with insulin resistance and increased Framingham risk scores and are more useful than the definitions that require measurement of insulin levels (WHO and EGIR).

Should we have more definitions of metabolic syndrome or simply take waist measurement?

The disorder now known as metabolic syndrome has been recognized for 50 years, but its multiple definitions have led to some confusion and even doubt about its very nature. Metabolic syndrome is directly linked to the presence of android obesity, which indicates insulin resistance and lies at the root of all risk factors and early indications of type 2 diabetes. It is diagnosed by systematic measurements of waist size and its direct interpretation taking ethnic origin into account. This pragmatic approach avoids the uncertainties generated by differing definitions and is subtler than the presence or absence of metabolic syndrome in a given patient. Drug-free treatment of an android obese patient is inexpensive and effective, but this apparently simple approach masks difficulties of application. However, these are sociological problems.

Features of the metabolic syndrome and prostate cancer in African-American men

BACKGROUND

Metabolic syndrome refers to a cluster of conditions that includes hypertension, dyslipidemia, central adiposity, and high blood glucose levels. Over the past decade, a growing body of literature suggests that metabolic syndrome may be associated with several different forms of cancer. Because prostate cancer risk is highest among African Americans, and these men, similarly, are more prone to developing specific features of the metabolic syndrome, including hypertension and type-2 diabetes, any relationships would have a significant impact on developing strategies for the primary prevention of prostate cancer.

METHODS

The Flint Men's Health Study is a community-based, case-control study of prostate cancer conducted exclusively among African Americans. Prostate cancer cases and controls completed an interviewer-administered questionnaire that asked about the respondent's history of high blood pressure and diabetes. All men also participated in a physical examination in which several measures of body composition, including waist circumference, were collected.

RESULTS

Hypertension was reported more commonly among men with prostate cancer (cases) compared with men in the control group (odds ratio [OR]. 2.4; 95% confidence interval [95% CI], 1.5-3.7), and cases were more likely to have a waist circumference >102 cm (OR, 1.8; 95% CI, 1.2-2.9). However, self-reported diabetes was not associated with prostate cancer risk. The men with prostate cancer also were more likely than controls to exhibit multiple syndrome characteristics (OR, 1.9; 95% CI, 1.2-3.0).

CONCLUSIONS

The current results indicated that features of the metabolic syndrome, specifically abdominal obesity and hypertension, are associated with prostate cancer in African-American men. This relationship, if it is proved causal, suggests that prevention or control of these conditions eventually may lead to a reduction in the incidence of prostate cancer in this high-risk minority group.

Interrelationship Between Insulin Resistance and Menopause on the Metabolic Syndrome and Its Individual Component Among Nondiabetic Women in the Kinmen Study

BACKGROUND

The literature to date is not clear as to whether any interactive effect exists between insulin resistance and menopause on the metabolic syndrome and its individual components. We explored this issue in 4107 homogeneous, nondiabetic Chinese women in the Kinmen Study.

METHODS

Overnight fasting blood samples were drawn for glucose, insulin, lipid, and other biochemical measurements. Demographic and clinical variables including body mass index, waist circumference, and blood pressure were measured and documented during face-to-face interviews with structured questionnaires. Menstrual history was used to define menopause as the absence of menses for 12 consecutive months.

RESULTS

Approximately 16% of premenopausal women (390/2423) were insulin-resistant. After adjustment for age, body mass index, lifestyle, and diet, both menopause and insulin resistance were independently and significantly correlated with metabolic syndrome. For each component of the metabolic syndrome, besides the main effect, the interaction (insulin resistance x menopause) had significant correlation with systolic blood pressure, diastolic blood pressure, and waist circumference.

CONCLUSIONS

Both insulin resistance and menopause have significant effects on metabolic syndrome independent of age and obesity. In premenopausal and nondiabetic women, various degrees of insulin resistance exist. The synergistic contribution of insulin resistance and menopause to components of the metabolic syndrome were observed with systolic blood pressure, diastolic blood pressure, and waist circumference. This requires further study.

Ethnic differences in cardiovascular risk factors in healthy Caucasian and South Asian individuals with the metabolic syndrome

BACKGROUND

The metabolic syndrome is a cluster of atherothrombotic risk factors that are commonly associated with insulin resistance.

OBJECTIVES

The aim of this study was to investigate ethnic differences in insulin resistance and non-traditional cardiovascular risk factors in relation to the International Diabetes Federation (IDF) definition of the metabolic syndrome.

PATIENTS AND METHODS

A total of 245 healthy South Asians and 245 age- and sex-matched Caucasians were studied. C-reactive protein (CRP), complement C3, plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator (t-PA) were measured and homeostasis model assessment-insulin resistance (HOMA-IR) was calculated from fasting plasma glucose and insulin levels.

RESULTS

Fifty Caucasian (20%) and 95 (39%) South Asian subjects had the metabolic syndrome as defined by the IDF. In South Asian subjects, HOMA-IR, CRP, C3, PAI-1 and t-PA were significantly higher in subjects with the metabolic syndrome. In contrast, in Caucasian individuals there was no difference in HOMA-IR or C3 levels and only CRP, PAI-1 and t-PA were higher in subjects with the metabolic syndrome. In a logistic regression model, plasma levels of CRP and PAI-1 were independent predictors of the metabolic syndrome in Caucasians, whereas plasma levels of C3 and t-PA as well as HOMA-IR were independent predictors of the metabolic syndrome in South Asian subjects.

CONCLUSIONS

In the cohort of individuals studied, the IDF definition of the metabolic syndrome was associated with insulin resistance in the South Asian but not the Caucasian population. This work also showed ethnic differences in non-traditional cardiovascular risk factors in the presence of the metabolic syndrome.

The 2005 Dietary Guidelines for Americans and insulin resistance in the Framingham Offspring Cohort

OBJECTIVE

The aim of this study was to examine the relationship between a diet consistent with the 2005 Dietary Guidelines for Americans (DGA), as assessed by the 2005 Dietary Guidelines for Americans Adherence Index (DGAI), and measures of insulin resistance in the Framingham Heart Study Offspring Cohort.

RESEARCH DESIGN AND METHODS

We examined cross-sectional associations between DGAI score and degree of insulin resistance as measured by the homeostasis model assessment of insulin resistance (HOMA-IR) and fasting insulin in 3,082 participants in the Framingham Offspring Cohort fifth examination (January 1991-June 1995).

RESULTS

Participants in the highest quintile category of the DGAI score had significantly lower HOMA-IR than those in the lowest quintile category after adjusting for age, sex, and waist circumference (6.4 compared with 6.7, P = 0.04). We observed a significant interaction between DGAI score and sex, and upon stratification, the association appeared to be largely confined to women (5.9 compared with 6.6, P < 0.001). No association was apparent in men (7.2 compared with 7.1, P = 0.30). Similar associations were evident between the DGAI score and fasting insulin.

CONCLUSIONS

Consumption of a diet consistent with the 2005 DGA may be an effective means to limit insulin resistance in women.

Assessment of metabolic profile in a clinical setting

PURPOSE OF REVIEW

The metabolic syndrome, a clustering of abnormalities such as hyperglycemia, insulin resistance, hypertension, dyslipidemia, and central obesity, is a principal risk factor for cardiovascular disease, the leading cause of morbidity and mortality in the Western world. There are several definitions of the metabolic syndrome, all aiming at including as many persons at risk as possible. The assessment and, hence, the identification of such persons in a clinical setting is of utmost importance.

RECENT FINDINGS

Clinicians should document the presence of central obesity, assessed by waist circumference measurement or determination of body composition using dual X-ray absorptiometry or measurement of visceral fat using computed tomography or magnetic resonance imaging. The presence of dyslipidemia, insulin resistance, and arterial hypertension constitutes the full profile of the metabolic syndrome. Nevertheless, elevated uric acid levels or presence of nonalcoholic fatty liver, or the diagnosis of the polycystic ovary syndrome in women of reproductive age, all are reflected in high risk of later occurrence of the full metabolic syndrome and atherosclerotic cardiovascular disease.

SUMMARY

Although no unified definition for the metabolic syndrome exists, it is important to identify persons at risk, in order to reduce the resultant high morbidity and mortality rates.