Appropriate waist circumference cutoff points for central obesity in Korean adults

Sasang constitutional types can act as a risk factor for insulin resistance

The prevalence of insulin resistance (IR) was found to differ across different constitutional types defined by the Sasang constitutional medicine, a sub-division of the Korean traditional medicine, implying that the constitutional type of an individual is a trait that can act as an independent risk factor for IR.

A comparison of predictability of cardiovascular events between each metabolic component in patients with metabolic syndrome based on the revised National Cholesterol Education Program criteria

PURPOSE

The prevalence of metabolic syndrome (MetS) generally varies depending on its diagnostic definition, and many different definitions inevitably lead to substantial confusion and lack of comparability between studies. Despite extensive research, there is still no gold standard for the definition of MetS, which continues to be a matter of debate. In this study, we investigate whether and to what extent its individual components are related to the risk of cardiovascular disease (CVD) in Korean population.

MATERIALS AND METHODS

We used data from the 2005 Korea National Health and Nutrition Examination Survey, which is a nationally representative survey of the noninstitutionalized civilian population. The study sample consisted of 1,406 Korean adults (587 men, 819 women) who were diagnosed with MetS based on the revised National Cholesterol Education Program (NCEP) criteria. Central obesity is defined as a waist circumference cutoff point reported in Asia-Pacific criteria for obesity based on waist circumference by the World Health Organization. CVD was defined as presence of stroke, myocardial infarction, or angina pectoris on a medical history questionnaire.

RESULTS

The CVD prevalence among the subjects was 6.8% for men and 8.6% for women. Besides age, the components of MetS showing a significant difference in the number of CVD events were high fasting glucose (FG) in men and high blood pressure (BP) and high FG in women. After adjusting for gender and age, high FG was shown to yield a significant difference (odds ratio: unadjusted 2.08, adjusted 1.81), alone among all MetS components. However, after adjusting for only age, no significant difference was found.

CONCLUSION

Fasting glucose level is the highest predicting factor for CVD in Korean patients with MetS based on the revised NECP definition.

Health-related quality of life in metabolic syndrome: The Korea National Health and Nutrition Examination Survey 2005

AIM

This study sought to assess the association between metabolic syndrome (MS) and health-related quality of life (HRQOL) in the general population.

METHODS

We analyzed data for 4463 adults, aged 30 years or older, from the Korea National Health and Nutrition Examination Survey 2005. "EuroQol 5D", which measures two dimensions, the EuroQol 5D index score (EQ-5D) and the EuroQol visual analogue scale (EQ-VAS), was used to evaluate HRQOL.

RESULTS

Mean scores for the EQ-5D in both sexes and EQ-VAS in women decreased with increasing number of MS components, and women's means for both scores were significantly lower than men's. In individual domains of HRQOL, men with more MS components tended to have higher odds ratios for decreased self-care, and women had decreased mobility, according to the EQ-5D. In men, high blood pressure led to decreased EQ-5D, and in women, abdominal obesity and high blood pressure did so. Additionally, we found that taking medication had an impact on decreased HRQOL, especially in subjects with impaired fasting glucose.

CONCLUSIONS

HRQOL was negatively associated with the number of MS components and it was decreased by taking hypoglycemic medications. This association differed by gender.

The relationship between normal serum uric acid and nonalcoholic fatty liver disease

The objective of the present study was to determine the relationship between serum uric acid (SUA) level and the presence of nonalcoholic fatty liver disease (NAFLD). We analyzed data of 9,019 Koreans who visited a health check up center. The SUA levels of all of these subjects were within the normal range. The participants were divided into 4 groups according to the quartiles of the SUA levels for both sexes. Hepatic steatosis was diagnosed on the basis of ultrasonographic findings. Multivariate logistic regression modeling was performed across the SUA quartiles. The presence of NAFLD and metabolic abnormalities were found significantly in subjects with high-normal SUA levels. After adjustment for age, metabolic components, and the liver-function test, the adjusted odds ratio (OR, 95% CIs) for the presence of NAFLD in the subjects with the highest SUA level was 1.46 (1.17-1.82) for men and 2.13 (1.42-3.18) for women, as compared to the subjects with the lowest SUA level. Our results suggest that increased SUA concentrations, even within the normal range, are independently associated with the presence of NAFLD.

Gender differences in the effect of obesity on chronic diseases among the elderly Koreans

The objective of this study is to investigate gender differences of obesity on major chronic diseases in elderly Korean males and females. This study applied a cross sectional design using the 2005 Korean National Health and Nutrition Examination Survey (KNHNES). We selected 508 elderly males and 830 elderly females who were 60 or more years old. Obesity was defined using Body Mass Index (BMI) (≥ 25) or Waist Circumference (WC) (≥ 90 for men and ≥ 85 for women). We applied a surveylogistic regression to determine gender differences in relation to the effect of obesity on eleven major chronic diseases. Using WC, 46.2% of females were obese compared to 34.3% for males. Similarly, using BMI, 42.2% of females were obese compared to 31.7% for males. While obese males and females had similar profiles for developing metabolic syndrome components including hypertension, dyslipidemia, and diabetes (odds ratios [ORs] were 1.8-2.6 for males and 1.7-2.5 for females), obese elderly females had additional risks for arthritis and urinary incontinence (ORs 1.5-1.8 for females) as well as higher prevalence for these diseases. A clearer understanding of gender differences in relation to the association between obesity and chronic diseases would be helpful for reducing the social burden of chronic diseases in the elderly.

The effects of hormone therapy on metabolic risk factors in postmenopausal Korean women

OBJECTIVE

We sought to assess the prevalence of metabolic syndrome (MetS) among Korean postmenopausal women and to investigate the effect of hormone therapy status and reproductive characteristics on body composition and MetS risk factors.

STUDY DESIGN

We performed a cross-sectional study involving a cohort of 2005 postmenopausal Korean women. We defined MetS using the modified National Cholesterol Education Program (NCEP) criteria proposed by the American Heart Association/National Heart, Lung, and Blood Institute guidelines. The criteria for abdominal obesity were adopted from the cut-offs suggested by the Korean Society for the Study of Obesity. Participants with three or more of the following conditions were classified as having MetS: waist circumference ≥ 85 cm; blood pressure ≥ 130/85 mmHg; fasting plasma triglycerides ≥ 150 mg/dl; high density lipoprotein cholesterol < 50 mg/dl; glucose ≥ 100 mg/dl and/or receiving treatment for their condition.

RESULTS

The prevalence of MetS was 22.1% in the study population and increased with age. After adjusting for age and related reproductive characteristics, it was found that ever-use of hormone therapy (prior or current) was associated with decreased risk of postmenopausal MetS. Among individual risk factors for MetS, current hormone therapy seemed to be associated with decreased prevalence of abdominal obesity and better glucose metabolism and prior use of hormone therapy were associated with lower risk of abdominal obesity and high blood pressure.

CONCLUSION

Postmenopausal hormone therapy is associated with decreased risk of MetS in postmenopausal Korean women.

Sex differences in the relationship between metabolic syndrome and pulmonary function: the 2007 Korean National Health and Nutrition Examination Survey

Pulmonary function impairment has a connection with abdominal obesity, type 2 diabetes, and insulin resistance. Sex differences in lifestyle factors, and pulmonary structure and function may affect pulmonary function in different manners. This study focused on sex differences in the relationship of MetS and its component with pulmonary function. Among 2,614 Korean adults (1,059 men; 1,555 women), pulmonary function was measured by the percentage of predicted forced vital capacity (FVC (%)) and a ratio between forced expiratory volume in 1 second (FEV(1))/FVC. FVC (%) and FEV(1)/FVC were compared according to the presence of MetS and its components. Multiple linear regression analysis was conducted to assess the association between FVC (%), FEV(1)/FVC and clinical variables. We found sex differences in the relationship of MetS and its components with pulmonary function. FVC (%) was significantly lower in subjects with MetS than in those without MetS in both men and women, and FEV(1)/FVC was lower in subjects with MetS only in women. Among components of MetS, waist circumference, blood pressure and fasting plasma glucose, and HDL-cholesterol were independently related to FVC (%) in men, whereas waist circumference was significantly associated with FVC (%) in women. Blood pressure was found to be an independent factor of FEV(1)/FVC in men, whereas blood pressure, fasting plasma glucose and HDL-cholesterol independently determined FEV(1)/FVC in women. These findings suggest that sex-specific association between MetS and lung function measures should be considered in clinical practice.

Serum carcinoembryonic antigen is associated with metabolic syndrome in female Korean non-smokers

BACKGROUND

Carcinoembryonic antigen (CEA), a serological marker of malignant tumors, demonstrates a modest increase under nonmalignant conditions and the pro-inflammatory features of CEA suggest that CEA may be related to insulin resistance and metabolic syndrome.

METHODS

A total of 7075 female Korean non-smokers who underwent health check-ups were analyzed in the present study. The interquartile cutoff values for serum CEA concentrations were 0.39, 0.84, and 1.40 ng/ml.

RESULTS

The prevalence of metabolic syndrome increased significantly with the increasing CEA quartiles, and the age-adjusted mean CEA concentration increased consistently with each additional component of metabolic syndrome. Logistic regression analysis adjusted for age, alcohol intake, exercise, body mass index, total cholesterol, WBC count, and hsCRP showed that the third and fourth CEA quartiles were associated with metabolic syndrome with odds ratios of 1.29 (95% CI 1.07 to 1.63 P<0.001) and 1.39 (95% CI 1.10 to 1.66, P<0.001), respectively.

CONCLUSION

In female Korean non-smokers, serum CEA was independently associated with metabolic syndrome. The pathophysiologic and clinical significance of these findings requires further investigation.

Sagittal abdominal diameter is a strong anthropometric measure of visceral adipose tissue in the Asian general population

OBJECTIVE

Finding the anthropometric measure of visceral obesity is essential to clinical practice, because it predicts cardiovascular and metabolic risks. Sagittal abdominal diameter (SAD) has been proposed as an estimate of visceral adipose tissue (VAT). The aim of the present study was to evaluate the usefulness of SAD in predicting visceral obesity by comparing SAD to other anthropometric measures.

RESEARCH DESIGN AND METHODS

Estimation of subcutaneous and visceral adipose tissue and measurement of SAD and transverse abdominal diameter using computed tomography at the umbilical level were obtained in 5,257 men and women who were enrolled in a health checkup program in Korea. To compare SAD to other anthropometric measures, linear regression analyses were used to determine correlations between anthropometrics and visceral obesity.

RESULTS

SAD showed a stronger correlation to VAT than waist circumference, BMI, and transverse abdominal diameter in the both sexes (men: r = 0.804, women: r = 0.724). Waist circumference showed generally stronger associations to subcutaneous adipose tissue (SAT) than to VAT (men: r = 0.789 vs. 0.705, women: r = 0.820 vs. 0.636). Even after subdividing according to age or BMI in both sexes and analyzing multiple regressions, SAD showed the strongest correlation to VAT.

CONCLUSIONS

SAD showed the strongest correlation to VAT irrespective of age, sex, and the degree of obesity compared with other anthropometric measures, whereas waist circumference may have a stronger correlation to SAT than to VAT. The clinical use of SAD has advantages over other anthropometric measures in predicting VAT.

General and abdominal obesity in South Korea, 1998-2007: gender and socioeconomic differences

OBJECTIVE

To examine national trends in prevalence and socioeconomic inequalities in both general (measured by body mass index) and abdominal obesity (measured by waist circumference) by gender and socioeconomic position (SEP) indicators.

METHODS

Data were from four rounds of nationally representative cross-sectional surveys for Korean men and women aged 25-64 (6,286 in 1998, 4,839 in 2001, 4,181 in 2005, and 2,006 in 2007). We calculated age-adjusted prevalence rates of overweight and abdominal obesity by gender and SEP indicators (education, occupational class, employment status and income) and examined trends of prevalence and its inequalities.

RESULTS

Overweight and abdominal obesity has significantly increased in Korean men (P for linear trend <0.01), not in women. For men, high SEP was associated with overweight and abdominal obesity, but the magnitude of socioeconomic differences in obesity measures generally remained unchanged during the study period. Among women, low SEP was associated with overweight. Interestingly, increasing inequalities in abdominal obesity according to education and income were found in women.

CONCLUSIONS

Clear gender differences were noted in (1) time trends of overweight and abdominal obesity, (2) relationships between the obesity measures and various SEP indicators, and (3) linear time trends of socioeconomic differentials in obesity.

Ketonuria after fasting may be related to the metabolic superiority

Obese individuals are less able to oxidize fat than non-obese individuals. Caloric reduction or fasting can detect ketonuria. We investigated the differences of metabolic parameters in the presence of ketonuria after a minimum 8 hr fast in a cross-sectional analysis of 16,523 Koreans (6,512 women and 10,011 men). The relationship between the presence of ketonuria of all subjects and prevalence of obesity, central obesity, metabolic syndrome, and obesity-related metabolic parameters were assessed. The ketonuria group had lower prevalence of obesity, central obesity, and metabolic syndrome than the non-ketonuria group. In addition, all metabolic parameters (including body weight, waist circumference, blood glucose, high-density lipoprotein, triglyceride, blood pressure, and insulin) were favorable in the ketonuria group than in the non-ketonuria group, even after adjustment for age, tobacco use, and alcohol consumption. The odds ratios of having obesity (odds ratio [OR]=1.427 in women, OR=1.582 in men, P<0.05), central obesity (OR=1.675 in women, OR=1.889 in men, P<0.05), and metabolic syndrome (OR=3.505 in women, OR=1.356 in men, P<0.05) were increased in the non-ketonuria group compared to the ketonuria group. The presence of ketonuria after at least an 8 hr fast may be indicative of metabolic superiority.

Trends in general and abdominal obesity among Korean adults: findings from 1998, 2001, 2005, and 2007 Korea National Health and Nutrition Examination Surveys

We examined trends in obesity among Korean adults, using body mass index (BMI) and waist circumference (WC) as reported in national surveys. Data (10,043 men and 12,758 non-pregnant women) were derived from four waves of the Korea National Health and Nutrition Examination Survey conducted in 1998, 2001, 2005, and 2007. Between 1998 and 2007, the distribution of BMI and WC showed shifts toward the right among men. Mean values of BMI and WC and the corresponding overweight (includes obesity) and obesity prevalences showed increasing trends in men but not in women. Women aged 60+ showed significant increases in obesity measures, including mean BMI and WC, and the associated prevalences. Among women aged 20-39, the prevalence of underweight increased significantly between 1998 and 2007, and BMI showed a decreasing tendency. These time trends in young women were the reverse of the trends in young men. In conclusion, policy efforts to abate overweight and obesity trends need to be exercised among men and older women. In addition, more national studies regarding potential increases in underweight among young women are warranted.

Randomized controlled trial to investigate the effects of a newly developed formulation of phentermine diffuse-controlled release for obesity

AIM

To evaluate the efficacy and safety of a newly developed formulation of phentermine diffuse-controlled release (DCR) in patients with obesity.

METHODS

This was a randomized, double-blind, placebo-controlled trial of 12 weeks of treatment with phentermine DCR 30 mg (n = 37) or placebo (n = 37), administered once daily in patients with obesity with controlled diabetes, hypertension or dyslipidaemia. The efficacy was evaluated by changes in body weight and waist circumference from baseline at 12 weeks and also changes in metabolic parameters, including lipid profiles and blood pressure.

RESULTS

The participants in the phentermine DCR group showed significant reductions in body weight (-8.1 ± 3.9 vs. -1.7 ± 2.9 kg, p < 0.001) and waist circumference (7.2 ± 0.5 vs. 2.1 ± 0.6 cm, p < 0.001) compared with those in the placebo group. Weight reductions of 5% or greater from the baseline (95.8 vs. 20.8%, p < 0.001) and 10% or more (62.5 vs. 4.7%, p < 0.001) were achieved in the DCR phentermine group and placebo group, respectively. Total cholesterol and low-density lipoprotein cholesterol (LDL-C) levels were significantly improved in the phentermine DCR group. However, there were no significant differences in systolic and diastolic blood pressure between the groups. Dry mouth and insomnia were the most common adverse events, but these were mild to moderate and transient.

CONCLUSIONS

Short-term phentermine DCR treatment resulted in significant reduction in weight and improvement of metabolic parameters, including waist circumference and some lipid profiles, without clinically severe adverse events. Further study is needed to show long-term efficacy and safety of phentermine DCR in Korean patients with obesity.

Risks for cardiovascular disease, stroke, ischaemic heart disease, and diabetes mellitus associated with the metabolic syndrome using the new harmonised definition: findings from nationally representative longitudinal data from an Asian population

OBJECTIVE

We examined the risk of cardiovascular disease, stroke, ischaemic heart disease, and diabetes with the metabolic syndrome according to the new harmonised definition and its components using a national longitudinal data set from an Asian population.

METHODS

Data of 9791 men and women aged 20+ from 1998 and 2001 Korea National Health and Nutrition Examination Surveys were individually linked to national hospitalisation and mortality data using unique personal identification numbers. During a 5.8-year follow-up through 2005, 288 incident cardiovascular events (184 strokes and 122 cases of ischaemic heart disease) and 85 new diabetes cases have been detected.

RESULTS

Men and women with the metabolic syndrome had 48%, 39%, 64%, and 127% greater risks of cardiovascular disease, stroke, ischaemic heart disease, and diabetes, respectively, than those without the metabolic syndrome. The increased risks of cardiovascular disease, ischaemic heart disease, and diabetes remained significant after adjusting for health behaviours, bio-clinical factors, family history, and socio-demographic factors. Analysis results on population attributable risks showed that about a quarter of total diabetes occurrence and more than 10% of cardiovascular disease was attributable to the metabolic syndrome. The number of metabolic syndrome components was linearly associated with risks of outcomes. High blood pressure was significantly associated with all four outcomes while hypertriglyceridemia and hyperglycemia were also important for ischaemic heart disease and diabetes, respectively.

CONCLUSIONS

Reduction of metabolic risk factors is necessary in South Korea to lower the burden of associated diseases, especially ever-increasing ischaemic heart disease and diabetes.

Cutoff points of abdominal obesity indices in screening for non-alcoholic fatty liver disease in Asians

BACKGROUND/AIMS

Abdominal obesity is associated with metabolic syndrome and non-alcoholic fatty liver disease (NAFLD). Although there have been many studies to determine the optimal cutoff points of waist circumference or visceral fat area in screening for metabolic syndrome, there have been no reports to establish adequate cutoff points of abdominal obesity indices in screening for NAFLD. Therefore, we examined the appropriate cutoff points of abdominal obesity indices associated with NAFLD in Korean men and women using receiver operating characteristic (ROC) curve analysis. Furthermore, we compared the usefulness of various abdominal obesity indices measured using computed tomography (CT), dual-energy X-ray absorptiometry (DXA) and anthropometric parameters for detecting NAFLD.

METHODS

We analysed the baseline data of an ongoing prospective, observational cohort study, including a total of 456 healthy subjects 20-88 years of age. NAFLD was diagnosed by unenhanced CT using the liver attenuation index.

RESULTS

All ROC curves of waist circumference, waist-to-height ratio, DXA-measured trunk fat mass and CT-measured visceral fat area were significantly above the diagonal line. There were no significant differences in the area under the curve values among these abdominal obesity indices in each gender. The appropriate cutoff point of waist circumference in screening for NAFLD was 89 cm for men and 84 cm for women and the optimal cutoff point of waist-to-height ratio was 0.52 for men and 0.53 for women with very high negative predictive values.

CONCLUSIONS

The simple anthropometric parameters, such as waist circumference and waist-to-height ratio, are as useful as DXA and CT for predicting NAFLD in Korean adults.

Association between serum vaspin concentrations and visceral adipose tissue in Korean subjects

Adipokines modulate multiple signaling pathways of insulin resistance via endocrine, paracrine, or autocrine mechanisms. Visceral adipose tissue (VAT)-derived serpin (vaspin) is a novel adipokine with potential insulin-sensitizing effects. We investigated the association between serum vaspin concentrations and abdominal adiposity. We recruited subjects (N = 150) aged 20 to 69 years who visited our hospital for regular health examinations. Abdominal VAT and subcutaneous adipose tissue areas were assessed by computed tomography. We measured serum vaspin concentrations by enzyme-linked immunosorbent assay. Statistical analysis was performed after stratification, using a homeostasis model for insulin resistance (HOMA-IR). Serum vaspin concentrations correlated positively with age (r = 0.196) when data from all subjects were analyzed. In the higher-HOMA-IR group, serum vaspin levels correlated more prominently with age (r = .344) and VAT area (r = .327) although these associations were not found in the lower-HOMA-IR group. In multivariate linear regression analysis, the VAT area was independently correlated with serum vaspin concentrations in the higher-HOMA-IR group. The association between serum vaspin concentrations and VAT differs according to insulin resistance. Insulin resistance might influence the correlation between serum vaspin concentration and VAT in human subjects.

Relationship between serum uric Acid levels, metabolic syndrome, and arterial stiffness in korean

Background and Objectives

Associations have been reported between the serum uric acid (SUA) level, metabolic syndrome (MS), and atherosclerosis. We have determined the relationship between the SUA level, MS, and arterial stiffness in Korean.

Subjects and Methods

Cross-sectional data from 1,276 adults who underwent routine laboratory tests and pulse wave velocity (PWV) measurements during a health check-up were analyzed in a gender-specific manner. None of the participants had atherosclerotic cardiovascular disease, diabetes, renal disease, or systemic disease, or were under treatment which would affect SUA levels, or taking medications for hypertension or dyslipidemia.

Results

After adjustment for age, smoking status, total cholesterol (TC), and creatinine, the odds ratios (ORs, 95% confidence interval) of gender-specific quartiles of SUA for MS were 1.0, 1.28 (0.66-2.47), 1.46 (0.76-2.82), and 2.21 (1.15-4.26) in females, and 1.0, 1.33 (0.82-2.17), 1.60 (0.96-2.66), and 2.03 (1.21-3.40) in males. However, after adjustment for waist circumference, there were no significant differences in the ORs among the SUA quartile groups in females and males (both, p=NS). The Pearson's correlation coefficients for the relationship between SUA levels and heart-femoral (hf) PWVs or brachial-ankle (ba) PWVs were not significant in females and males (r=0.054 and r=0.015, respectively, in females; r=-0.036 and r=-0.015, respectively, in males; all, p=NS).

Conclusion

An elevated SUA level is associated with abdominal obesity among the MS components, but the SUA level is not associated with PWV in females or males.

Optimal cut-off values and population means of waist circumference in different populations

Abdominal obesity is a risk factor for cardiometabolic disease, and has become a major public health problem in the world. Waist circumference is generally used as a simple surrogate marker to define abdominal obesity for population screening. An increasing number of publications solely rely on the method that maximises sensitivity and specificity to define ‘optimal’ cut-off values. It is well documented that the optimal cut-off values of waist circumference vary across different ethnicities. However, it is not clear if the variation in cut-off values is a true biological phenomenon or an artifact of the method for identifying optimal cut-off points. The objective of the present review was to assess the relationship between optimal cut-offs and population waist circumference levels. Among sixty-one research papers, optimal cut-off values ranged from 65·5 to 101·2 cm for women and 72·5 to 103·0 cm for men. Reported optimal cut-off values were highly correlated with population means (correlation coefficient: 0·91 for men and 0·93 for women). Such a strong association was independent of waist circumference measurement techniques or the health outcomes (dyslipidaemia, hypertension or hyperglycaemia), and existed in some homogeneous populations such as the Chinese and Japanese. Our findings raised some concerns about applying the sensitivity and specificity approach to determine cut-off values. Further research is needed to understand whether the differences among populations in waist circumference were genetically or environmentally determined, and to understand whether using region-specific cut-off points can identify individuals with the same absolute risk levels of metabolic and cardiovascular outcomes among different populations.

Optimal waist circumference cutoff value reflecting insulin resistance as a diagnostic criterion of metabolic syndrome in a nondiabetic Korean population aged 40 years and over: the Chungju Metabolic Disease Cohort (CMC) study

PURPOSE

We aimed at determining the cutoff value of waist circumference with respect to its ability to reflect insulin resistance in a Korean population.

MATERIALS AND METHODS

A total of 8,817 subjects aged 40 years and over were analyzed. Insulin resistant individuals were defined as those who had the highest quartile value of the homeostasis model assessment of insulin resistance (HOMA-IR) in a non-diabetic population. Receiver operating characteristic (ROC) curve analysis and multiple logistic regression analysis were applied.

RESULTS

The cutoff value of waist circumference reflecting insulin resistance from the ROC analysis was 84.4 cm for men and 80.6 cm for women. Sensitivity and specificity were 70.0% and 54.2% in men and 71.1% and 59.3% in women, respectively. After being controlled for other covariates, the odds ratio for the risk of insulin resistance using < 70 cm of waist circumference as a reference increased significantly in the category of 85.0-89.9 cm for men and 80.0-84.9 cm for women. In addition, statistically significant associations were consistently observed over the category of 85.0-89.9 cm for men and 80.0-84.9 cm for women.

CONCLUSION

The optimal cutoff value for waist circumference reflecting insulin resistance is considered to be 85 cm for men and 80 cm for women, suggesting that the Asian criterion of abdominal obesity (90 cm for men and 80 cm for women) as a component of metabolic syndrome (MetS) might not be applicable for middle-aged to older men in Korea.

Optimal cut-off point of waist circumference for the diagnosis of metabolic syndrome in Japanese subjects

Metabolic syndrome (MetS) has been redefined by a new criterion in Japan, in which waist circumference cut-off points, that is 85 cm for men and 90 cm for women, are used; however, objections are rising against this criterion. The present study examined the criterion for waist circumference to predict the accumulation of the components of MetS. In the present study, we used data for 5972 Japanese people who received annual health examinations, and 621 men (16.3%) and 51 women (2.4%) were diagnosed as having MetS. A cut-off point as a predictor for two or more components of MetS was evaluated by the sensitivity/specificity and a receiver operating characteristic analysis. The optimal point of waist circumference was estimated as being approximately 84 cm for men and 80 cm for women. We therefore recommend revising the cut-off value for the criterion of MetS in women according to our results and studies from other investigators. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2010.00020.x, 2010).

The association of metabolic syndrome with periodontal disease is confounded by age and smoking in a Korean population: the Shiwha-Banwol Environmental Health Study

AIM

Because metabolic syndrome (MS) is pro-inflammatory and periodontitis is inflammatory, we issued the hypothesis that MS (the explanatory variable) is associated with periodontitis (the outcome variable). This study aimed to examine the link between MS and periodontitis among Koreans.

MATERIALS AND METHODS

From the Shiwha-Banwol Environmental Health Study, 1046 subjects aged 18 years or older were cross-sectionally surveyed. All participants underwent comprehensive dental and medical health examinations. The community periodontal index was used to assess periodontitis. Age, gender, monthly family income, smoking, drinking, frequency of daily teeth brushing, and physical activity were evaluated as confounders.

RESULTS

MS was strongly associated with periodontitis [odds ratio (OR): 1.7, 95% confidence interval (CI): 1.22-2.37], and MS with more components had a higher association. The association was higher for elders aged 65 years or more, males, and smokers. MS including both high glucose and hypertension had a higher association with the OR of 2.19 (95% CI: 1.23-3.90) comparing with other types of MS.

CONCLUSIONS

Our results suggested that MS might be associated with periodontitis and the association was confounded by age, gender, and smoking. MS with high glucose and hypertension showed the higher impact on this link.

Association between alcohol intake amount and prevalence of metabolic syndrome in Korean rural male population

Moderate alcohol consumption is known to be associated with a reduced risk of cardiovascular disease and mortality. However, few studies reported that long-term alcohol drinking may increase the prevalence of central obesity, and cardiovascular disease. We examined the association between metabolic syndrome, nutritional factors and alcohol intake amount in Korean male rural population. We performed a cross-sectional analysis on data from Korean Rural Genomic Cohort (KRGC) study. We used multiple logistic regression analysis to estimate the adjusted odds ratio of metabolic syndrome according to alcohol intake amount categories (never, 0-16 g/day, 16-40 g/day, and >40 g/day). The age adjusted odds ratio for the prevalence of metabolic syndrome was significantly increased in the quartile with the highest alcohol consumption compared to the non-alcohol drinking group (1.33; C.I., 1.11-1.59). These results were similar in the high energy intake group, but not in the low energy intake group. Waist circumference, blood pressure, and serum triglyceride levels were significantly higher in the quartile with the highest alcohol consumption compared to the non-alcohol drinking group. These results suggest that large alcohol consumption is associated with metabolic syndrome and may be a modifiable risk factor of metabolic syndrome especially in subjects with high calorie intake.

Optimal waist circumference cutoff values for metabolic syndrome diagnostic criteria in a Korean rural population

The Korean Society for the Study of Obesity (KSSO) has defined the waist circumference cutoff value of central obesity as 90 cm for men and 85 cm for women. The purpose of this investigation was to determine the corresponding waist circumference values. A total of 3,508 persons in the Korean Rural Genomic Cohort Study were enrolled in this survey. Receiver operating characteristic (ROC) curve analysis was used to find appropriate waist circumference cutoff values in relation to insulin resistance determined by homeostasis model assessment for insulin resistance (HOMA-IR), body mass index (BMI), and components of metabolic syndrome. The optimal waist circumference cutoff values were 87 cm for men and 83 cm for women by ROC analysis to HOMA-IR and 86 cm for men and 83 cm for women by ROC analysis to value with more than two components of metaobolic syndrome. By using a BMI > or =25 kg/m(2), 86 cm for men and 82 cm for women were optimal waist circumference cutoff values. In this study, we suggest that the most reasonable waist circumference cutoff values are 86-87 cm for men and 82-83 cm for women.

Normal range of alanine aminotransferase concentration is associated with carotid atherosclerosis

OBJECTIVE

To investigate whether alanine aminotransferase (ALT), even within the reference range, is associated with atherosclerotic burden in apparently healthy adults.

METHODS

This was an observational study performed on 830 healthy individuals with normal ALT concentration (<or=40U/L). Atherosclerotic burden was assessed by carotid arterial intima-media thickness (IMT). All subjects were divided according to the quartile based on their ALT concentrations.

RESULTS

Despite all subjects having a normal ALT concentration, ultrasonographic liver steatosis was observed in 48.4% and 36.7% of men and women, respectively. In both genders, subjects in the highest quartile of ALT concentration had a significantly higher waist circumference, triglyceride concentration, HOMA-IR, a higher prevalence of metabolic syndrome, and a greater severity of ultrasonographic liver steatosis than did those in the lower quartiles. In women, the carotid IMT increased significantly with increasing quartiles of ALT concentration (0.62+/-0.14mm, 0.66+/-0.15mm, 0.69+/-0.15mm, vs. 0.72+/-0.24mm; P for trend<0.001). Based on multivariate regression analysis, the serum ALT, even within the normal range, was associated with the carotid IMT in both men and women, and independently of traditional cardiovascular risk factors.

CONCLUSIONS

ALT concentrations, albeit within the reference range, were associated with atherosclerotic burden in healthy adults.

Metabolic syndrome and carotid artery parameter in Koreans aged 50 years and older

BACKGROUND

Few studies have reported on the relationship between metabolic syndrome (MetS) and carotid artery structure. The objective of this study was to examine the relationship between MetS and carotid artery parameters such as the common carotid artery intima-media thickness (CCA-IMT), plaques, and the diameter of the common carotid artery (CCAd).

METHODS AND RESULTS

The study population consisted of 1.730 community-dwelling Koreans aged 50 years and older without hypertension, diabetes mellitus or dyslipidemia. MetS was defined according to the modified National Cholesterol Education Program's Adult Treatment Panel III criteria. The risk for abnormal CCA-IMT (>or=1.00 mm) was significant in women with MetS (odds ratio (OR) 2.22; 95% confidence interval (CI) 1.14-4.31), but not in men with MetS (OR 1.06; 95%CI 0.39-2.91). No significant relationship between MetS and carotid plaques was observed in either sex. The relationship between MetS and high CCAd (highest quintile) was significant in both men (OR 2.19; 95%CI 1.38-3.49) and women (OR 2.02; 95%CI 1.39-2.94).

CONCLUSIONS

MetS independently correlates with carotid atherosclerosis and carotid enlargement. The effect of MetS on carotid atherosclerosis is more pronounced in women than in men.

Prevalence of metabolic syndrome and obesity in adolescents aged 12 to 19 years: comparison between the United States and Korea

This study compared the prevalence of metabolic syndrome (MetS), its risk factors, and obesity in adolescents in the United States (US) and Korea. Data were obtained from 2003-2004 US National Health and Nutrition Examination Survey (NHANES) and 2005 Korea NHANES for adolescents aged 12-19 yr in the US (n=734) and in Korea (n=664). The 2007 International Diabetes Federation (IDF) pediatric definition for diagnosis of MetS and the 2000 US Growth Charts and 2007 Korea Growth Charts for assessment of obesity were utilized. The prevalence of metabolic syndrome in US and Koreans was 5.5% and 2.5%, respectively. The prevalence of obesity was 18.1% in US compared to 9.0% in Koreans. The prevalence of abdominal obesity, hyperglycemia, and hypertriglyceridemia were higher in the US, whereas that of low HDL-C levels was higher in Korea. Despite the doubled prevalence for the single entities of MetS and obesity in the US, the prevalence of MetS in obese US and Koreans did not differ (20.8% and 24.3%, respectively). In conclusion, there are differences in the prevalence of MetS, obesity, and the individual MetS risk factors between the US and Korean adolescents; however, the risk of MetS among obese adolescents is similar in both countries.

The cutoff values of visceral fat area and waist circumference for identifying subjects at risk for metabolic syndrome in elderly Korean: Ansan Geriatric (AGE) cohort study

Background

In Korea, the cutoff values of waist circumference (WC) for the identification of metabolic syndrome (MetS) were suggested to be 90 cm for men and 85 cm for women based on the analysis mainly in middle-aged adults. As aging is associated with increased fat, especially abdominal visceral fat, the cutoff value of WC may differ according to age. In addition, the usefulness of visceral abdominal fat area (VFA) to predict MetS in the elderly has not been studied yet. We aimed to suggest WC and VFA criteria and to compare the predictability of WC and VFA to identify people at risk for MetS.

Methods

A total of 689 elderly subjects aged ≥63 years (308 men, 381 women) were chosen in this cross-sectional study from an ongoing, prospective, population-based study, the Ansan Geriatric (AGE) cohort study. VFA was measured by single slice abdominal computed tomography scanning. The metabolic risk factors except WC (plasma glucose, blood pressure, serum triglycerides and HDL cholesterol levels) were defined using modified NCEP-ATP III criteria. We estimated the accuracy of VFA and WC for identifying at least two of these factors by receiver operating characteristic (ROC) curve analysis.

Results

Two hundred three of 308 men and 280 of 381 women had ≥2 metabolic risk factors. The area under the ROC curve (AUC) value for VFA to predict the presence of ≥2 metabolic risk factors was not significantly different from that for WC (men, 0.735 and 0.750; women, 0.715 and 0.682; AUC values for VFA and WC, respectively). The optimal cutoff points for VFA and WC for predicting the presence of ≥2 metabolic risk factors were 92.6 cm² and 86.5 cm for men and 88.9 cm² and 86.5 cm for women.

Conclusion

WC had comparable power with VFA to identify elderly people who are at risk for MetS. Elderly Korean men and women had very similar cutoff points for both VFA and WC measurements for estimating the risk of MetS. Age-specific cutoff point for WC might be considered to identify subjects at risk for MetS.

Multiple biomarkers and their relative contributions to identifying metabolic syndrome

BACKGROUND

Several biological markers have been identified as risk factors for cardiovascular disease and are associated with increased risk of metabolic syndrome. We thus compared biomarkers and their association with metabolic syndrome.

METHODS

We measured the white blood cell count, high-sensitivity C-reactive protein, homeostasis model assessment of insulin resistance (HOMA-IR), homocysteine, cystatin C, gamma-glutamyl transferase (GGT), alanine aminotransferase (ALT) and uric acid levels in 4624 adults without a medical history of cardiovascular disease. Metabolic syndrome was defined using criteria from the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) and the International Diabetes Federation (IDF).

RESULTS

The HOMA-IR and GGT were most strongly correlated with metabolic syndrome. The area under the receiver operating characteristic curve was highest for the HOMA-IR (0.773, 95% CI: 0.755-0.791 [men]; 0.792, 95% CI: 0.775-0.808 [women]) and the GGT (0.687, 95% CI: 0.667-0.706 [men]; 0.721, 95% CI: 0.703-0.739 [women]) in AHA/NHLBI criteria. The best cut-off value of HOMA-IR and GGT for identifying metabolic syndrome was (1.22, 30 IU/l [men], 1.28, 15 IU/l [women]).

CONCLUSION

HOMA-IR and GGT are most strongly associated with metabolic syndrome, suggesting that theses biomarkers may contribute to identifying metabolic syndrome more than other factors.

Optimal cutoff points of waist circumference for the criteria of abdominal obesity: comparison with the criteria of the International Diabetes Federation

BACKGROUND

There are few studies that compare measures of diagnostic accuracy for selected waist cutoff points and the criteria of abdominal obesity given by the International Diabetes Federation (IDF) and the National Cholesterol Education Program (NCEP).

METHODS AND RESULTS

The present study utilized data from the Third Korean National Health and Nutrition Examination Survey. Analyses for receiver-operating characteristic (ROC) curve were performed with data for 4,677 men and women aged 20-80 years who reported being free of a physician-diagnosed cardiovascular disease or cancer. On the basis of measures of diagnostic accuracy, including minimum distance to ROC curve and Youden index, waist circumference of 84-86 cm for men and of 78-80 cm for women were found to be optimal cutoff points. The study also demonstrated that the use of smaller waist circumference for diagnosis of the metabolic syndrome decreases discrepancies between the prevalence of the IDF-defined metabolic syndrome and that of the NCEP-defined metabolic syndrome.

CONCLUSIONS

Waist circumference of 90 cm, the cutoff point given by the IDF for Asian men, may not be an appropriate value for Korean men, while its cutoff point for Asian women is appropriate for Korean women.

Lower waist-circumference cutoff point for the assessment of cardiometabolic risk in Koreans

AIMS

To determine the appropriate cutoff value of waist circumference associated with cardiometabolic risk factors in Koreans.

METHODS

Clinical and laboratory data on 31,076 Korean adults (age 20-89 years, 40% women) were recorded at regular health check-ups. Receiver operating characteristic curves were used to determine the cutoff values of waist circumference with respect to myocardial ischemia, hypertension, diabetes, and multiple risk factors for metabolic syndrome.

RESULTS

Age-adjusted odds ratios for myocardial ischemia, diabetes, hypertension, and multiple components of metabolic syndrome for one standard-deviation increase in waist circumference were 1.45, 1.37, 1.55, and 1.89 for men, and 1.28, 2.03, 1.64, and 2.08 for women, respectively. The cutoff value showing the maximum sensitivity plus specificity for detecting myocardial ischemia was 87 cm for men and 74 cm for women. The cutoff values for discrimination of hypertension, diabetes, and multiple risk factors for metabolic syndrome, were 84, 85, and 83 cm, respectively, for men, and 77, 77, and 76 cm, respectively, for women.

CONCLUSIONS

The waist-circumference cutoff values for cardiometabolic disease and its risk factors are lower than those recommended for Asians by the WHO. Waist-circumference cutoff for defining metabolic syndrome should be lowered in the Korean population.

Metabolic syndrome and quality of life (QOL) using generalised and obesity-specific QOL scales

OBJECTIVES

We investigated the association between metabolic syndrome (MS) and health-related quality of life (HRQOL) assessed using generalised and obesity-specific QOL instruments.

METHODS

We recruited 456 outpatients [age: 19-81 years, body mass index (BMI): 16.3-36.7 kg/m2] in the primary care division from 12 general hospitals in Korea. HRQOL was measured using EuroQol comprising the health states descriptive system (EQ-5D) and visual analogue scale (EQ-VAS) as a general instrument. The Korean Obesity-related QOL scale (KOQOL) composed of six domains was used as a disease-specific QOL instrument. MS was defined on the basis of International Diabetes Federation (IDF) criteria with Korean-specific waist circumference cutoffs (men: 90 cm, women: 85 cm).

RESULTS

Subjects with MS displayed significantly higher impairment of EQ-5D and KOQOL. Binary logistic regression analysis of MS patients with controls for age, gender, smoking, alcohol, exercise, education, income, marital status and medication history disclosed odds ratio (OR) values of 2.13 (1.33-3.41) for impaired total KOQOL, 2.07 (1.31-3.27) for impaired physical health, 1.63 (1.03-2.60) for impaired work-related health, 2.42 (1.45-4.04) for impaired routine life, 2.08 (1.27-3.40) for impaired sexual life and 2.56 (1.59-4.11) for diet distress. Among the EQ-5D dimensions, only pain/discomfort displayed a significantly increased OR of 1.60 (1.01-2.56) in MS group.

CONCLUSIONS

Subjects with MS displayed a significantly impaired HRQOL compared with those without MS. MS and HRQOL were more strongly associated in obesity-specific QOL than in generalised QOL.

Association between inappropriateness of left ventricular mass and left ventricular diastolic dysfunction: a study using the tissue Doppler parameter, e/e'

BACKGROUND AND OBJECTIVES

The structural significance of the inappropriateness of left ventricular mass (iLVM) is known to be an important prognostic factor for cardiovascular events; however, the functional changes associated with iLVM have not been established. This study was performed to determine if diastolic dysfunction is associated with iLVM using a tissue Doppler technique.

SUBJECTS AND METHODS

Three hundred sixty consecutive subjects, including 221 hypertension patients from the echocardiography database, were analyzed. Regarding the appropriateness of left ventricular (LV) mass, an observed/predicted ratio of LV mass (OPR) >130% was defined as inappropriate. Echocardiographic parameters, including early diastolic peak velocity (E)/late diastolic peak velocity (A), deceleration time (DT), isovolumetric relaxation time (IVRT), and E/early mitral annulus velocity (E'), were compared between the appropriate LV mass (aLVM) group and the iLVM group.

RESULTS

Among transmitral flow parameters, only the E velocity was negatively correlated with the OPR when adjusted for age (adjusted r=-0.107, p=0.04). Based on multiple regression analysis, the OPR (beta=0.163, p=0.003), as well as age (beta=0.286, p=0.0001), systolic blood pressure (beta=0.120, p=0.019), fasting blood glucose (beta=0.098, p=0.042), and male gender (beta=0.157, p=0.002) were independent factors determining E/E'. The cholesterol level was not an independent factor (beta=-0.059, p=0.355). In the iLVM group (n=105), the adjusted E/E' was higher than in the aLVM group (n=255; 11.7+/-3.4 vs. 10.8+/-3.1, p=0.02), while the peak E flow velocity was significantly lower than in the aLVM group (70.9+/-15.1 vs. 75.5+/-17.6, p=0.03).

CONCLUSION

Inappropriateness of LV mass is independently associated with increased E/E'. Thus, E/E' may be a useful parameter for the evaluation of diastolic dysfunction.

The association between sleep duration and general and abdominal obesity in Koreans: data from the Korean National Health and Nutrition Examination Survey, 2001 and 2005

This study aimed to investigate the association between self-reported sleep duration and general and abdominal obesity in Korean adults. A total of 8,717 adults aged 20-65 years from the Korean National Health and Nutrition Examination Survey (KNHANES) 2001 and 2005 were included. General obesity was defined as BMI >or=25 kg/m(2) and abdominal obesity as waist circumference >or=90 cm in men and >or=85 cm in women. To control for sociodemographic and lifestyle factors and comorbidities, multivariable logistic regression was used to calculate the adjusted odds ratios (ORs) and 95% confidence intervals (CIs) of general and abdominal obesity across the following sleep duration categories: <or=5, 6, 7, 8, and >or=9 h/day. Mean sleep duration (+/-s.d.) was 6.9 +/- 1.3 h. Those sleeping <or=5 h/day had the highest BMI and waist circumference compared with those sleeping 7, 8, or >or=9 h/day (P < 0.05 for all comparisons). After controlling for sociodemographic and lifestyle factors, the adjusted ORs (95% CIs) associated with sleeping <or=5 h/day (vs. 7 h/day) were 1.25 (1.06-1.48) for general obesity and 1.24 (1.03-1.48) for abdominal obesity. Further adjustment for hypertension and diabetes mellitus did not significantly affect the associations. These data suggest that short sleep duration is significantly associated with a modest increase in general and abdominal obesity in Korean adults.

Adipogenic risk factor differences between Korean and white adults--potential role of plasma free fatty acid and adiponectin

Asian adults are at greater risk for metabolic abnormalities (insulin resistance, dyslipidemia) at the same body mass index (BMI) than are whites. Elevated free fatty acids (FFA) and decreased adiponectin are linked with these same metabolic abnormalities. We tested the hypothesis that fasting plasma FFA are greater and adiponectin concentrations are lower in Korean than white adults matched for age, sex, and BMI. Plasma FFA and adiponectin concentrations were analyzed using a microfluorometric assay and radioimmunoassay, respectively. Fasting plasma FFA concentrations were not different (P = .51) between Korean and white subjects (208 [183-232] vs 215 [168-262] mumol/L, median and 95% confidence interval). Despite similar body composition in the 2 groups, the plasma adiponectin concentrations in Koreans were significantly lower than those in whites in men, women, and total subgroups (adjusted mean +/- SEM: 4.9 +/- 0.8 vs 9.1 +/- 0.8 microg/mL, P = .004; 8.9 +/- 1.0 vs 13.2 +/- 1.0 microg/mL, P = .006; and 6.5 +/- 0.6 vs 11.1 +/- 0.6 microg/mL, P Collapse

Key Words

• ethnicity
• body composition
• lipolysis

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MESH Headings

• Adipogenesis/physiology
• Adiponectin/blood
• Adult
• Asian People/statistics & numerical data
• Body Mass Index
• Dyslipidemias/ethnology
• Dyslipidemias/metabolism
• Fatty Acids, Nonesterified/blood
• Female
• Humans
• Insulin Resistance
• Male
• Middle Aged
• Risk Factors
• White People/statistics & numerical data

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Grants

• R01 DK045343 NIDDK NIH HHS
• UL1 RR024150 NCRR NIH HHS
• DK45343 NIDDK NIH HHS

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Affiliation(s)

Sangyeoup Lee Center for Obesity, Nutrition and Metabolism and Department of Family Medicine, Pusan National University Hospital and Medical Education Unit, Pusan National University School of Medicine, and Medical Research Institute, Pusan National University, Busan, South Korea Endocrine Research Unit, Mayo Clinic, Rochester, Minnesota, U.S.A
Michael D. Jensen Endocrine Research Unit, Mayo Clinic, Rochester, Minnesota, U.S.A

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Collaborators Collapse

An association between colonic adenoma and abdominal obesity: a cross-sectional study

BACKGROUND

Colorectal adenoma is a precursor lesion of colorectal cancer and thus, it is an important target for preventing colorectal cancer. Only a few studies suggest an association between colorectal adenoma and obesity, but results show considerable heterogeneity. In this study, we investigated the association between colorectal adenoma and waist circumference.

METHODS

165 adenoma cases and 365 polyp-free controls with a normal colon were compared in this cross-sectional study. Subjects underwent screening colonoscopy by experienced endoscopists. Demographic data, including smoking habit, were obtained by interview and waist circumference and anthropometric measurements were examined. Dietary intakes were evaluated using a food frequency questionnaire, and abdominal obesity was evaluated by measuring waist circumference. Statistical analysis was performed using SPSS for 13.0.

RESULTS

Age, waist circumference, and BMI were significantly higher in cases than controls. And smokers and men were more prevalent among cases than controls.Among the abdominal obese subjects, 45.6% had 1 or more adenoma, and 9.0% of these had advanced adenoma, whereas among subjects with a normal waist circumference, only 25.7% had 1 or more adenomas. The prevalence of adenoma was higher among abdominal obese group (P < 0.05). Logistic regression analysis showed that abdominal obesity was associated with an increased risk of colorectal adenoma (OR, 2.74; 95% CI, 1.66~4.51 in men, OR, 2.58; 95% CI, 1.08~6.12 in women). These associations persisted even after adjusting for BMI. While BMI was found to be weekly associated with the risk of adenoma among men at the highest BMI levels. However, BMI was not associated with the risk for adenoma after adjusting for waist circumference.

CONCLUSION

Our data suggest that abdominal obesity is associated with an increased risk of colorectal adenoma.