OBJECTIVES: This study was performed to assess the association between physical activity and the clustering of metabolic abnormalities among Korean children. The effect of substituting moderate to vigorous physical activity for the time spent in inactivity was examined as well. METHODS: The study subjects were comprised of 692 (354 boys, 338 girls) 4th grade elementary school students. We used a modified form of the physical activity questionnaire that was developed in the Five-City Project. The subjects with clustering of metabolic abnormalities were defined as having two or more of the following five characteristics: waist circumference > or =90 %, systolic or diastolic blood pressure > or =90 %, fasting glucose > or =110 mg/dl, triglycerides > or =110 mg/dl and HDL cholesterol < or =40 mg/dl. We calculated the odds ratios to assess the effect of substituting moderate to vigorous physical activity for time spent in inactivity. RESULTS: The risk of clustered metabolic abnormalities was inversely correlated with the increased time spent on moderate to vigorous physical activity, but the correlation was not significant. The odds ratio for clustering of metabolic abnormalities that represented the effect of substituting moderate to vigorous physical activity for 30minutes of sedentary activity was 0.87 (95% CI=0.76-1.01). CONCLUSIONS: These findings suggest that substituting moderate to vigorous physical activity for sedentary activity could decrease the risk of clustered metabolic abnormalities.
Blood Glucose/metabolism ; Blood Pressure ; Child ; Cholesterol, HDL ; *Exercise ; Female ; Humans ; Male ; Metabolic Syndrome X/diagnosis/*epidemiology ; Questionnaires ; Risk Factors ; Triglycerides/blood ; Urban Population ; Waist Circumference

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.
Blood Glucose/analysis ; Blood Pressure ; Body Weight ; Cross-Sectional Studies ; *Fasting ; Female ; Humans ; Insulin/blood ; Ketosis/*complications/diagnosis ; Lipoproteins, HDL/blood ; Male ; Metabolic Syndrome X/*complications/epidemiology ; Obesity/complications/epidemiology ; Odds Ratio ; Time Factors ; Triglycerides/blood ; Waist Circumference

The metabolic syndrome (MetS) is the clustering of cardiovascular risk factors and known as a powerful predictor of diabetes and cardiovascular disease. Glycated hemoglobin (HbA1c) is used as one of the diagnostic criteria for diabetes and category of increased risk for diabetes. We examined the usefulness of HbA1c as a diagnostic tool for MetS and to determine the cut-off value of HbA1c as a criterion for MetS, in non-diabetic Korean subjects. We analyzed 7,307 participants (male: 4,181, 57%) in a medical check-up program, and applied the newly recommended guidelines of the International Diabetes Federation for diagnosis of MetS. The mean HbA1c was 5.54% in all subjects and showed no significant difference between genders. Using receiver-operating characteristic curve, HbA1c value corresponding to the fasting plasma glucose value of 100 mg/dL was 5.65% (sensitivity 52.3%, specificity 76.7%). The prevalence of MetS was 8.5% according to the IDF guideline and 10.9% according to HbA1c value of 5.7%, showing 69.5% agreement rate. The detection rate of MetS increased to 25.7% using the HbA1c criterion of 5.7% instead of fasting hyperglycemia. This study suggests that HbA1c might be used as a diagnostic criterion for MetS and the appropriate cut-off value of HbA1c may be 5.65% in this Korean population.
Adult ; Blood Glucose/analysis ; Chromatography, High Pressure Liquid ; Female ; Hemoglobin A, Glycosylated/*analysis ; Humans ; Male ; Metabolic Syndrome X/*diagnosis/epidemiology ; Middle Aged ; Prevalence ; ROC Curve ; Risk Factors

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.
Age Factors ; Blood Glucose/analysis ; Cardiovascular Diseases/epidemiology/*etiology ; Chi-Square Distribution ; Female ; Health Promotion ; Health Surveys ; Humans ; Hypertension/complications/epidemiology ; Male ; Metabolic Syndrome X/complications/*diagnosis/epidemiology ; Middle Aged ; Odds Ratio ; Republic of Korea/epidemiology ; Risk Factors ; Sex Factors

BACKGROUND/AIMS: This study evaluated the relationship between thyroid nodules and metabolic syndrome (MS) and its components in apparently healthy Koreans. METHODS: We reviewed the records of 3,298 subjects with no noticeable symptoms who underwent thyroid ultrasound imaging as part of a routine check-up between July 2009 and June 2010; of these, 1,308 were excluded based upon predefined criteria. Among the remaining 1,990 patients, we examined the association between MS and its components and the incidence of thyroid nodules. RESULTS: Of the 1,990 subjects included in this study, 38.4% (n = 764) had thyroid nodules and 12.7% (n = 253) had MS. Female sex, older age, higher body mass index, larger waist circumference, higher glycated hemoglobin level, lower thyroid stimulating hormone level, and presence of MS were all closely related with the presence of thyroid nodules (all p < 0.05). Furthermore, the relevant number of MS components showed a positive linear correlation with the occurrence of thyroid nodules (p < 0.001). Evidence of MS alone was not independently associated with thyroid nodules after adjusting for sex and age in a multivariate binary logistic regression analysis; however, glycated hemoglobin for females and waist circumference for males, as well as both age and thyroid stimulating hormone for all patients, were identified as independent predictors for the existence of thyroid nodules (all p < 0.05). CONCLUSIONS: This study suggests a positive relationship between the components of MS and thyroid nodules in an ostensibly healthy Korean population. Our data support the idea that the recent increase in thyroid nodules is partly due to increases in both MS and obesity.
Adult ; Biomarkers/blood ; Body Mass Index ; Chi-Square Distribution ; Cross-Sectional Studies ; Diabetes Mellitus/diagnosis/epidemiology ; Female ; Hemoglobin A, Glycosylated/analysis ; Humans ; Incidence ; Linear Models ; Logistic Models ; Male ; Metabolic Syndrome X/blood/diagnosis/*epidemiology ; Middle Aged ; Multivariate Analysis ; Obesity/diagnosis/epidemiology ; Odds Ratio ; Republic of Korea/epidemiology ; Retrospective Studies ; Risk Factors ; Thyroid Nodule/blood/diagnostic imaging/*epidemiology ; Thyrotropin/blood ; Waist Circumference

BACKGROUND/AIMS: The existence of an association between thyrotropin (thyroid stimulating hormone, TSH) levels and metabolic derangement in euthyroid subjects is controversial. We examined the association between high normal TSH levels and metabolic syndrome in healthy young women. METHODS: The study recruited 2,760 young female volunteers (age, 18 to 39 years) with TSH levels in the normal range (0.3 to 4.5 mU/L). We defined metabolic syndrome using the 2007 International Diabetes Federation criteria. Using a TSH level of 2.5 mU/L as an upper reference limit, as recommended by the National Academy of Clinical Biochemistry, we divided the subjects into high-(n = 453) and low-TSH groups (n = 2,307). RESULTS: The prevalence of metabolic syndrome was significantly higher in the high-TSH group than in the low-TSH group (7.5% vs. 4.8%, p = 0.016). Central obesity (22.3% vs. 17.3%, p = 0.012) and hypertriglyceridemia (8.0% vs. 4.2%, p = 0.0007) were significantly more frequent in the high-TSH group than in the low-TSH group. Waist circumference, systolic and diastolic blood pressure, and triglycerides were significantly associated with the TSH level after adjusting for age and body mass index (BMI). Subjects in the high-TSH group had a 2-fold greater risk of metabolic syndrome than subjects in the low-TSH group after adjusting for age and BMI (odds ratio, 1.9; 95% confidence interval, 1.1 to 3.2). CONCLUSIONS: Healthy young women with TSH levels > 2.5 mU/L should be assessed for the presence of metabolic syndrome, even if their TSH levels are in the normal range.
Adolescent ; Adult ; Age Factors ; Biological Markers/blood ; Female ; Humans ; Hypertension/blood/epidemiology ; Hypertriglyceridemia/blood/epidemiology ; Linear Models ; Metabolic Syndrome X/*blood/diagnosis/epidemiology ; Obesity, Abdominal/blood/epidemiology ; Odds Ratio ; Prevalence ; Republic of Korea ; Risk Factors ; Sex Factors ; Thyrotropin/*blood ; Up-Regulation ; Young Adult

BACKGROUND/AIMS: The aim was to determine which of three sets of metabolic syndrome (MetS) criteria (International Diabetes Federation [IDF], National Cholesterol Education Program Adult Treatment Panel III [ATP III], and European Group for the Study of Insulin Resistance [EGIR]) best predicts the coronary artery calcification (CAC) score in a cross-sectional study. This has not been evaluated in previous studies. METHODS: A total of 24,060 subjects were screened for CAC by multi-detector computed tomography. The presence of CAC was defined as a CAC score > 0. The odds ratio for the presence of CAC was analyzed for three different sets of MetS criteria and according to number of MetS components. RESULTS: CAC was observed in 12.6% (3,037) of the subjects. Patients with MetS, as defined by the IDF, ATP III, and EGIR criteria, had a CAC rate of 23.0%, 25.1%, and 29.5%, respectively (p < 0.001). Comparisons of C statistics for multivariate regression models revealed no significant difference among the three sets of criteria. After adjustment for risk factors, the ATP III criteria produced a slightly higher odds ratio for CAC compared with the other criteria, but this difference was not significant. The risk factor-adjusted odds ratio for the presence of CAC increased from 1 to 1.679 as the number of MetS components defined by ATP III increased from 0 to > or = 3 (p for trend < 0.001). CONCLUSIONS: The presence of MetS was associated with the presence of CAC. There was no significant difference among the three sets of MetS criteria in terms of the ability to predict CAC. An increase in the number of MetS components was associated with an increased odds of CAC.
Adult ; Asymptomatic Diseases ; Biological Markers/blood ; Calcium/*analysis ; Coronary Angiography/methods ; Coronary Artery Disease/blood/*epidemiology/radiography ; Coronary Vessels/*chemistry/radiography ; Cross-Sectional Studies ; Female ; Humans ; Male ; Metabolic Syndrome X/blood/diagnosis/*epidemiology ; Middle Aged ; Multidetector Computed Tomography ; Multivariate Analysis ; Odds Ratio ; Predictive Value of Tests ; Prevalence ; Republic of Korea/epidemiology ; Risk Assessment ; Risk Factors ; Vascular Calcification/blood/*epidemiology/metabolism/radiography

Dry eye syndrome (DES) is recognized as a public health concern. One of the pathophysiologies in the development of DES is inflammation, and metabolic syndrome (MetS), which is highly prevalent in the general population, is a well-known chronic and systemic inflammatory condition. Despite the increasing interest regarding a relationship between DES and MetS, information is lacking on the association between DES and MetS and its individual components. We investigated the association between DES symptoms and MetS and its components among adults aged ≥ 19 years using population-based data from the Korea National Health and Nutrition Examination Survey V. A sample group of 15,294 adults (42.67% men and 57.33% women) completed household interviews in which they provided blood (for high-density lipoprotein cholesterol, triglyceride, and glucose) and anthropometric measurements (including waist circumference, weight, and height) to define MetS. We also collected information regarding sociodemographic and behavioral risk factors. The survey results showed that 11.50% of men and 22.35% of women experienced DES and 5.30% of patients had both DES and diagnosis of MetS, including 204 men and 606 women. Thus, no significant difference was observed between DES and the diagnosis of MetS according to sex (P = 0.4008 in men; P = 0.0804 in women); however, a significant association was observed between DES and hypertriglyceridemia in women (OR, 1.13; 95% CI, 1.01-1.29). Therefore, hypertriglyceridemia might be an important factor in the association between DES and MetS. Further longitudinal research is needed to evaluate this relationship.
Adult ; Aged ; Blood Glucose/analysis ; Body Height ; Body Weight ; Cholesterol, HDL/blood ; Cross-Sectional Studies ; Dry Eye Syndromes/complications/*diagnosis/epidemiology ; Female ; Humans ; Hypertriglyceridemia/complications/diagnosis ; Interviews as Topic ; Male ; Metabolic Syndrome X/complications/*diagnosis/epidemiology ; Middle Aged ; Nutrition Surveys ; Prevalence ; Republic of Korea/epidemiology ; Risk Factors ; Sex Factors ; Triglycerides/blood ; Waist Circumference ; Young Adult

BACKGROUND/AIMS: An association between serum uric acid and cancer risk has been noted over the past few decades. There is ongoing debate about whether hyperuricemia represents an independent risk factor for colorectal neoplasm. We investigated the association between serum uric acid and prevalence of colorectal adenoma considering numerous confounding factors. METHODS: A cross-sectional study was performed with individuals who underwent a routine health check-up examination, including a screening colonoscopy and blood chemistry. The association between serum uric acid and prevalence of colorectal adenoma was estimated from the results of a logistic regression analysis. RESULTS: Of the 1,066 participants, 402 had colorectal adenoma (37.7%). In univariate models, the prevalence of colorectal adenoma was higher in participants in the fourth quartile uric acid level, compared to those in the first quartile uric acid level (OR, 1.67; 95% CI, 1.17-2.42; p=0.004). However, no significant association was detected between serum uric acid and prevalence of colorectal adenoma in multiple logistic regression analysis. A number of metabolic syndrome components exhibited a strong association with the prevalence of colorectal adenoma in the multivariate model (OR, 3.46 for highest vs. lowest; 95% CI, 1.30-9.20; p=0.021). Moreover, serum uric acid was strongly associated with metabolic syndrome-associated variables, including waist circumference, fasting blood glucose, systolic blood pressure, diastolic blood pressure, triglyceride, and high-density lipoprotein. CONCLUSIONS: Uric acid is not an independent risk factor for colorectal adenoma but is a risk indicator for metabolic syndrome-related colorectal adenoma.
Adenoma/*diagnosis/epidemiology/etiology ; Adult ; Asian Continental Ancestry Group ; Blood Glucose/analysis ; Blood Pressure ; Colonoscopy ; Colorectal Neoplasms/*diagnosis/epidemiology/etiology ; Cross-Sectional Studies ; Female ; Humans ; Logistic Models ; Male ; Metabolic Syndrome X/*diagnosis ; Middle Aged ; Odds Ratio ; Prevalence ; Republic of Korea ; Risk Factors ; Triglycerides/blood ; Uric Acid/*blood/urine ; Waist Circumference

BACKGROUND/AIMS: Many patients are diagnosed with cryptogenic hepatocellular carcinoma (HCC) without metabolic syndrome (MS). We investigated the risk factors for cryptogenic HCC in patients with a low body mass index (BMI) or without MS. METHODS: Thirty-six patients were diagnosed with cryptogenic HCC over a 10-year period at a tertiary research hospital. Data including BMI score and risk factors for MS were analyzed retrospectively. Patients with fewer than two risk factors for MS (n = 16) were compared with those with two or more risk factors (n = 20). Patients with high BMI (> or = 23 kg/m2, n = 20) were also compared with those with lower BMI (n = 16). RESULTS: Patients with fewer than two risk factors for MS were significantly more likely to smoke and be hepatitis B surface antibodies (anti-HBs)-positive vs. patients with two or more risk factors. However, only smoking was statistically significant on multivariate analysis. Peaks of BMI were observed in two regions. Lower BMI was significantly associated with the presence of anti-HBs compared with high BMI, although this association was not statistically significant on multivariate analysis. CONCLUSIONS: Smoking is a potential risk factor for cryptogenic HCC in patients without MS. Remote hepatitis B virus infection may be a risk factor for cryptogenic HCC in patients without MS or with a low BMI.
Aged ; Aged, 80 and over ; *Body Mass Index ; Carcinoma, Hepatocellular/*epidemiology ; Chi-Square Distribution ; Female ; Hepatitis B/diagnosis/epidemiology ; Hepatitis B Antibodies/blood ; Hepatitis B Surface Antigens/immunology ; Humans ; Liver Neoplasms/*epidemiology ; Logistic Models ; Male ; Metabolic Syndrome X/*epidemiology ; Middle Aged ; Multivariate Analysis ; Odds Ratio ; Republic of Korea/epidemiology ; Retrospective Studies ; Risk Assessment ; Risk Factors ; Smoking/adverse effects/epidemiology ; Time Factors