Prevalence of the metabolic syndrome among Korean adults according to the criteria of the International Diabetes Federation

Nomenclature Dilemma of Metabolic Associated Fatty Liver Disease (MAFLD): Considerable Proportions of MAFLD Are Metabolic Healthy

BACKGROUND & AIMS

The purpose of this study was to investigate the proportion of subjects with metabolic dysfunction-associated fatty liver disease (MAFLD) and to assess the degree of hepatic fibrosis and cardiovascular risk in metabolically healthy MAFLD subjects.

METHODS

A total of 6740 subjects who underwent both magnetic resonance elastography and abdominal ultrasound were included in this study. Significant (≥3.0 kPa) and advanced (≥3.6 kPa) hepatic fibrosis were evaluated by magnetic resonance elastography. The metabolic unhealthy status among subjects with MAFLD was defined as the presence of diabetes or 2 or more metabolic risk abnormalities.

RESULTS

The prevalence of MAFLD among the health examination cohort was 44.5% (3002 of 6740). A total of 26.6% (800 of 3002) of MAFLD subjects were metabolically healthy (≤1 risk factors and no diabetes), and 56.3% of MAFLD subjects (1691 of 3002) did not have metabolic syndrome. Hepatic fibrosis burden and cardiovascular risk were significantly higher in the metabolic unhealthy MAFLD group than in the healthy control group. However, the prevalence of significant (5.8% vs 4.3%; P = .099) and advanced hepatic fibrosis (0.8% vs 0.7%; P = .934) did not differ between the metabolically healthy MAFLD and healthy control groups. The prevalence of carotid artery plaque in the metabolically healthy MAFLD (32.7% vs 30.7%; P = .453) group was not different from that in the healthy control group.

CONCLUSIONS

Contrary to the definition of MAFLD, a non-negligible number of metabolically healthy individuals are included in the MAFLD group. The metabolic healthy MAFLD group showed a comparable fibrosis burden and prevalence of carotid artery plaque compared with the healthy control group.

Metabolic and Obesity Phenotype Trajectories in Taiwanese Medical Personnel

The distribution of metabolic and obesity phenotypes in Taiwanese medical personnel is unknown. In this study, trajectory analysis with repeated measurements was used to explore the development and associated risk factors of different metabolic and obesity phenotypes in hospital staff from a Taiwanese medical center. The results demonstrated that metabolically unhealthy workers presented with a higher body mass index (BMI) compared with their metabolically healthy counterparts. Male and aged > 40 years hospital workers were more likely to be in a deleterious metabolic/obesity state. Meanwhile, profession and working hours were not significantly associated with the development of certain phenotypes in our study. These results shed light on the necessity of adequate data retrieval regarding working hours, and a nuanced examination of working conditions among different professions. Our findings are helpful for the development of advanced guidance regarding health promotion in hospital workers.

Fibrosis Burden of Missed and Added Populations According to the New Definition of Metabolic Dysfunction-Associated Fatty Liver

Recently, the classification of fatty liver and the definition for non-alcoholic fatty liver disease (NAFLD) have been challenged. Herein, we aim to evaluate the burden of hepatic fibrosis in the missed and added populations following the proposal of the new definition of metabolic dysfunction-associated fatty liver (MAFLD) in a health check-up cohort. A total of 6775 subjects underwent both magnetic resonance elastography (MRE) and an abdominal ultrasound at 13 nationwide health check-up centers in Korea. Significant and advanced hepatic fibrosis was defined as ≥3.0 kPa and ≥3.6 kPa in the MRE test, respectively. The prevalence of sonographic fatty liver (FL) was 47.4%. Among the subjects with sonographic FL, 77.3% and 94% are compatible with NAFLD and with the new MAFLD definitions, respectively. Moreover, 72% of FL cases belong to both the NAFLD and MAFLD definitions, whereas 1.4% is compatible with neither. The population compatible with the MAFLD definition has the following coexisting liver diseases: alcohol-related (71.9%), hepatitis B (23.9%), hepatitis C (0.4%), and both alcohol and viral hepatitis (2.8%). The prevalence of significant and advanced hepatic fibrosis is considerable in the MAFLD-only group. However, the prevalence of significant and advanced hepatic fibrosis is similar in the NAFLD-only group, and neither the NAFLD nor MAFLD group compared to healthy controls. The added population (MAFLD-only group), according to the new MAFLD definition, has a higher metabolic and fibrosis burden when compared to those in the missed population (NAFLD-only group).

Biological age and lifestyle in the diagnosis of metabolic syndrome: the NHIS health screening data, 2014-2015

Metabolic syndrome (MS) is diagnosed using absolute criteria that do not consider age and sex, but most studies have shown that the prevalence of MS increases with age in both sexes. Thus, the evaluation of MS should consider sex and age. We aimed to develop a new index that considers the age and sex for evaluating an individual's relative overall MS status. Data of 16,518,532 subjects (8,671,838 males and 7,846,694 females) who completed a validated health survey of the National Health Insurance Service of the Republic of Korea (2014‒2015) were analyzed to develop an MS-biological age model. Principal component score analysis using waist circumference, pulse pressure, fasting blood sugar, triglyceride levels, and high-density lipoprotein level, but not age, as independent variables were performed to derive an index of health status and biological age. In both sexes, the age according to the MS-biological age model increased with rising smoking and alcohol consumption habits and decreased with rising physical activity. Particularly, smoking and drinking affected females, whereas physical activity affected males. The MS-biological age model can be a supplementary tool for evaluating and managing MS, quantitatively measuring the effect of lifestyle changes on MS, and motivating patients to maintain a healthy lifestyle.

Sex Difference in the Association Between Metabolic Syndrome and Obstructive Coronary Artery Disease: Analysis of Data from the KoRean wOmen'S chest pain rEgistry (KoROSE)

Background: The sex-related impact of metabolic syndrome (MetS) on obstructive coronary artery disease (OCAD) has not been well evaluated. Methods: A total of 1156 patients (62 years and 58% women) with chest pain undergoing invasive coronary angiography (CAG) were recruited from the database of the nation-wide chest pain registry. MetS was defined according to the criteria of the International Diabetes Federation. OCAD was defined as ≥50% stenosis of the left main coronary artery and/or ≥70% stenosis of any other coronary arteries. Results: Women were older than men (65 vs. 59 years, p < 0.001). OCAD (32.0% vs. 30.9%) and MetS (27.8% vs. 27.9%) prevalence rates were similar in both sexes (p > 0.05). The presence of MetS was associated with higher prevalence of OCAD in women (24.5% vs. 47.3%, p < 0.001), but not in men (31.0% vs. 34.3%, p = 0.487). The linear association between the number of components meeting MetS criteria and OCAD prevalence was significant in both sexes (p < 0.001 for each), but it was stronger in women than in men (Chi-square value: 81.9 vs. 14.8, p < 0.001). In a multivariable model, the presence of MetS was independently associated with OCAD in women even after controlling for potential confounders (odds ratio, 1.92; 95% confidence interval, 1.31-2.81; p = 0.001). Conclusions: In patients with chest pain undergoing invasive CAG, the association between the number of components meeting MetS criteria and OCAD prevalence was stronger in women than in men.

The effect of obesity on patients with mild chronic obstructive pulmonary disease: results from KNHANES 2010 to 2012

PURPOSE

A low body mass index has been associated with high mortalities in patients with chronic obstructive pulmonary disease (COPD), and studies reveal that obesity aggravates the clinical effects of COPD. We investigated the impact of obesity on patients newly identified with COPD.

PATIENTS AND METHODS

This population-based, cross-sectional study, used data from the Korea National Health and Nutrition Examination Survey (KNHANES) conducted from 2010 to 2012. Through analyses of data from this survey, we compared concurrent comorbid diseases, symptoms, and lung functions between an obese and nonobese group of patients with COPD.

RESULTS

In total, 618 participants were diagnosed with COPD and the average forced expired volume in 1 s (FEV1) was 79.47%±0.69%. Of the total, 30.5% of the subjects were categorized into an obese group. Subjects in the obese group were likely to have metabolic syndrome (P<0.001), hypertension (P=0.02), and a higher number of comorbidities compared to the nonobese group (2.3±0.1 vs 2.0±0.1, P=0.02). In addition, subjects in the obese group showed a lower forced vital capacity (FVC) than subjects in the nonobese group, even after adjusting for covariates (average FVC%, 89.32±1.26 vs 92.52%±0.72%, P=0.037). There were no significant differences in the adjusted FEV1% and adjusted FEV1/FVC between the groups.

CONCLUSIONS

Among subjects newly identified with mild COPD, participants in the obese group had more comorbid conditions and showed a lower FVC compared with subjects in the nonobese group, even after adjustment of covariates. These findings show that a combination of obesity and COPD may be a severe phenotype; therefore, early attention should be paid to obesity for the management of COPD patients.

Models for estimating the metabolic syndrome biological age as the new index for evaluation and management of metabolic syndrome

Purpose

This study aims to propose a metabolic syndrome (MS) biological age model, through which overall evaluation and management of the health status and aging state in MS can be done easily. Through this model, we hope to provide a novel evaluation and management health index that can be utilized in various health care fields.

Patient and methods

MS parameters from American Heart Association/National Heart, Lung, and Blood Institute guidelines in 2005 were used as biomarkers for the estimation of MS biological age. MS biological age model development was done by analyzing data of 263,828 participants and clinical application of the developed MS biological age was assessed by analyzing the data of 188,886 subjects.

Results

The principal component accounted for 36.1% in male and 38.9% in female of the total variance in the battery of five variables. The correlation coefficient between corrected biological age and chronological age in males and females were 0.711 and 0.737, respectively. Significant difference for mean MS biological age and chronological age between the three groups, normal, at risk and MS, was seen (P<0.001).

Conclusion

For the comprehensive approach in MS management, MS biological age is expected to be additionally utilized as a novel evaluation and management index along with the traditional MS diagnosis.

Cardiovascular disease incidence, mortality and case fatality related to diabetes and metabolic syndrome: A community-based prospective study (Ansung-Ansan cohort 2001-12)

BACKGROUND

We evaluated the separate and combined effect of metabolic syndrome (MS) and diabetes on incident cardiovascular disease (CVD), CVD mortality and case fatality risk (CFR).

METHODS

8898 subjects were categorized into four groups on the basis of the presence of MS and diabetes (with MS, with diabetes, with both or without either). We compared the development of CVD events, mortality and CFR.

RESULTS

Over a mean follow-up of 8.0 years, 690 subjects developed CVD. There were 434 deaths, of which 101 were from CVD. The presence of diabetes alone, MS alone, or both was associated with an increased risk for incident CVD and CVD mortality. Compared with the MS only group, the adjusted hazard ratio (HR) for CVD events and CVD mortality in the diabetes only group was 1.07 (95% confidence interval [CI] 0.77-1.48) and 2.02 (95% CI 0.99-1.72), respectively. Among individuals with diabetes, the presence of MS did not significantly increase CVD risk and CVD mortality. The adjusted odds ratio for CVD CFR, including adjustment for the presence of MS, in subjects with diabetes versus without diabetes was 2.11 (95% CI 1.34-3.31).

CONCLUSIONS

There was no difference in the risk of incident CVD between individuals with diabetes alone and MS alone, whereas CVD mortality was much higher in individuals with diabetes only. The presence of MS did not exhibit an additive effect on CVD risk and mortality in individuals with diabetes. Individuals with diabetes had a higher CVD case fatality regardless of the presence of MS.

Age and gender differences in the clustering of metabolic syndrome combinations: A prospective cohort research from the Kerman Coronary Artery Disease Risk Study (KERCADRS)

BACKGROUND

The features of metabolic syndrome (MetS) and its components are now different in Iran compared to western countries.

AIMS

The aim of this study was to provide estimates of the prevalence of the different MetS combinations in younger and older men and women in Iran.

METHODS

A detailed interview regarding social demographics risk profile, and components of MetS was administered according to the Kerman Coronary Artery Disease Risk Study (KERCADRS) as population-based, epidemiological research among a cohort of 6000 individuals that residence in Kerman city.

RESULTS

The overall prevalence of MetS was 25.2% in men and 42.5% in women considering the International Diabetes Federation (IDF) criteria and 31.0% in men and 38.0% in women when the National Cholesterol Education Program (NCEP) definition was applied. MetS was significantly more prevalent in females, using both definitions. The prevalence of MetS increased with age in both gender when both syndrome criteria were considered. The prevalence of different combinations of the syndrome by both definitions peaked in the age range 51-60 years among both men and women. The appearance of each component was observed earlier in women than men.

CONCLUSION

The prevalence of the MetS in the State of Kerman, a great province in the south-east of Iran is estimated as 35.0%, higher than in most developed countries and some other Middle-East regions, with generally higher prevalence rates for women. The prevalence of MetS increases with age in both genders with earlier appearance in men.

Association between metabolic syndrome, smoking status and coronary artery calcification

Coronary artery calcification (CAC), an indicator of coronary artery stenosis, is an independent risk factor of ischemic heart disease. Smoking increases the risk of metabolic syndrome (MS) and cardiovascular disease. Almost no previous studies have evaluated the combined effect of MS and smoking status on CAC. Therefore, in this study we examined the relationships between CAC, MS, and smoking. This study included 775 adult males without histories of cardiovascular disease who visited the Health Promotion Center at the University Hospital in Gyeonggi-do, Republic of Korea from January 2, 2010 to December 31, 2012. All subjects were screened for CAC by multi-detector computed tomography (MDCT). CAC increased significantly with age and body mass index (BMI). Among MS components, abdominal obesity and elevated fasting blood glucose were correlated with CAC. After adjusting for age and BMI, MS was associated with a 1.46-fold increase in CAC (95% CI:1.02-2.09), abdominal obesity was associated with a 1.45-fold increase (95% CI:1.04-2.04), elevated fasting blood glucose was associated with a 2-fold increase (95% CI:1.36-2.94), and MS and smoking combined were associated with 2.44-fold increase in CAC. Thus, the combination of smoking and MS had a greater impact on CAC than any single factor alone. MS is correlated with an increased risk of CAC, and a combination of MS and smoking is associated with even greater risk. These findings can be used to prevent cardiovascular disease in adults.

Quantitative analysis of pancreatic echogenicity on transabdominal sonography: correlations with metabolic syndrome

PURPOSE

To attempt a quantitative analysis of pancreatic echogenicity on transabdominal ultrasonography (US) and evaluate the correlation between pancreatic echogenicity and metabolic syndrome (MetS).

METHODS

We retrospectively evaluated transabdominal sonograms from 286 subjects. Mean pancreatic body brightness, mean perihepatic fat brightness, and the pancreato-perihepatic fat index (PPHFI) were measured, and reproducibility was analyzed using intraclass correlation coefficients. Associations between the PPHFI and MetS components were analyzed. The optimal PPHFI cutoff value to predict MetS was calculated.

RESULTS

Reproducibility was good for mean pancreatic body brightness, mean perihepatic fat brightness, and PPHFI with intraclass correlation coefficients of 0.98, 0.95, and 0.95, respectively. Each MetS component showed a significant association with PPHFI. Waist circumference had the strongest association (r = 0.55, p < 0.0001). PPHFI was significantly higher in the MetS (+) group than the MetS (-) group (p < 0.0001), and PPHFI was an independent factor predicting MetS (p = 0.02; odds ratio, 2.89). The best PPHFI cutoff value to predict MetS was 1.97, with a relatively high negative predictive value of 94.1%.

CONCLUSIONS

We quantitatively analyzed pancreatic echogenicity using the PPHFI on US and found that an increased PPHFI was significantly correlated with MetS. Because increased PPHFI on US may indicate MetS, radiologists and clinicians need to be aware of its implications.

Clinical characteristics of metabolic syndrome in Korea, and its comparison with other Asian countries

Metabolic syndrome is referred to as syndrome X or insulin resistance syndrome, and is primarily composed of abdominal obesity, diabetes, glucose intolerance, dyslipidemia and high blood pressure. Asians have a lower frequency of obesity than Caucasians, but have an increasing tendency toward metabolic syndrome. Thus, metabolic syndrome poses a major challenge for public health professionals, and is set to become a social and economic problem in Asian populations. Most data on metabolic syndrome are based on studies from Western countries with only limited information derived from Asian populations. Recently, several studies were carried out on a large scale that represents the general Korean population. The prevalence of metabolic syndrome in Korean adults has varied depending on the study designs and different criteria, but shows a distinct increasing trend of metabolic syndrome driven by an increase in abdominal obesity and dyslipidemia. Given the rapid economic progression of Korea over the past 30 years along with a rise of the aged population, it is expected that the prevalence of metabolic syndrome will further increase. Therefore, a proactive strategy at the governmental level for metabolic syndrome prevention should be implemented, reducing abdominal obesity and dyslipidemia. Healthy dietary habits and regular exercise should be emphasized as a part of such a strategy.

A new insight into the role of plasma fibrinogen in the development of metabolic syndrome from a prospective cohort study in urban Han Chinese population

BACKGROUND

Elevated levels of fibrinogen may contribute to a prothrombotic state. Cross-sectional studies suggest fibrinogen possibly linked with MetS/its components, while results of cohort studies remain controversial. Thus, this study was designed to identify the association of plasma fibrinogen with metabolic syndrome (MetS) and further to clarify the role of fibrinogen in the development of MetS.

METHODS

A large-scale prospective cohort study was conducted in routine health check-up population. 6209 participants free of MetS at baseline were included in the original cohort, with annually routine health check-up for incident MetS from 2005 to 2011. Then, 4 pre-MetS sub-cohorts, with overweight, hypertension, hyperglycemia and dyslipidemia at baseline respectively, were also created from the original cohort. Various strategies of Cox model analysis were performed for attempting to confirm the role of fibrinogen in the development of MetS.

RESULTS

Total MetS incidence density was 75.58 per 1000 person-years. Cox regression analysis by adjusting for potential confounders as well as four MetS components showed a significant effect of fibrinogen on MetS just in female, with risk ratio (RR) (95 % CI) of 1.48 (1.02, 2.13) for Q4 vs. Q1. Further analysis in the 4 pre-MetS female sub-cohorts revealed this significant effect only in overweight sub-cohort, with RR (95 % CI) of 1.97 (1.20, 3.23), but no significant interaction of overweight with fibrinogen on MetS was revealed in original female cohort. Then, stratification analysis among the 4 sub-groups of fibrinogen quartiles showed that effects of overweight on MetS were different among the 4 sub-groups of fibrinogen quartiles, with RR of 2.98 for Q1, 4.40 for Q2, 3.93 for Q3, and 4.82 for Q4 respectively.

CONCLUSIONS

Fibrinogen was associated with MetS just in overweight sub-cohort of female individuals, and fibrinogen might be a potential modifier in the pathway from overweight to MetS.

Predicting visceral obesity based on facial characteristics

Background

Visceral obesity is associated with facial characteristics and chronic disease, but no studies on the best predictor of visceral obesity based on facial characteristics have been reported. The aims of the present study were to investigate the association of visceral obesity with facial characteristics, to determine the best predictor of normal waist and visceral obesity among these characteristics, and to compare the predictive power of individual and combined characteristics.

Methods

Cross-sectional data were obtained from 11347 adult Korean men and women ranging from 18 to 80 years old. We examined 15 facial characteristics to identify the strongest predictor of normal and viscerally obese subjects and assessed the predictive power of the combined characteristics.

Results

FD_94_194 (the distance between both inferior ear lobes) was the best indicator of the normal and viscerally obese subjects in the following groups: Men-18-50 (p ≤ 0.0001, OR = 4.610, AUC = 0.821), Men-50-80 (p ≤ 0.0001, OR = 2.624, AUC = 0.735), and Women-18-50 (p ≤ 0.0001, OR = 2.979, AUC = 0.76). In contrast, FD_43_143 (mandibular width) was the strongest predictor in Women-50-80 (p ≤ 0.0001, OR = 2.099, AUC = 0.679). In a comparison of the combined characteristics, the area under the receiver operating characteristic curve (AUC) and the kappa values of the 4 groups ranged from 0.826 to 0.702 and from 0.483 to 0.279, respectively. The model for Men-18-50 showed the strongest predictive values and the model for Women-51-80 had the lowest predictive value for both the individual and combined characteristics.

Conclusions

In both men and women, the predictive power of the young and middle-age groups was better than that of the elderly groups for predicting normal waist and viscerally obese subjects for both the individual and combined characteristics. The predictive power appeared to increase slightly with the combined characteristics.

The application of data mining to explore association rules between metabolic syndrome and lifestyles

This study used an efficient data mining algorithm, called DCIP (the data cutting and inner product method), to explore association rules between the lifestyles of factory workers in Taiwan and the metabolic syndrome. A total of 1,216 workers in four companies completed a lifestyle questionnaire. Results of the questionnaire survey were integrated into the workers' health examination reports to form an attribute database of the metabolic syndrome. Among the association rules derived by DCIP, 80% of those on the list of the top 15 highest support counts are corroborated by medical literature or by healthcare professionals. These findings prove that data mining is a valid and effective research method, and that larger sample sizes will likely produce more accurate associations connecting the metabolic syndrome to specific lifestyles. The rules already verified can serve as a reference guide for the health management of factory workers. The remaining 20%, while still lacking hard evidence, provide fertile ground for future research.

Correlation of metabolic syndrome with urinary stone composition

OBJECTIVE

To determine the correlation between metabolic syndrome and the distribution of stone components in patients with urolithiasis.

METHODS

Between January 2007 and December 2010, renal or ureteral stones were collected from 712 patients (432 males, 280 females) who underwent surgical intervention at three hospitals in South Korea. Metabolic syndrome was defined according to the latest definition of the International Diabetes Federation, using ethnicity- and sex-specific cut-off values for central obesity. Patients were assessed by factors used in metabolic syndrome. All urinary stones were analyzed using infrared spectrophotometry and categorized according to their main component.

RESULTS

The patients' mean age was 55.9 years (range 19-93 years). Of the 712 patients, 347 (48.7%; 205 males, 142 females) had a diagnosis of metabolic syndrome. Calcium oxalate (71.5%), uric acid (15.3%), carbonate apatite (8.0%) and struvite (4.1%) calculi were found as the main stone components. Overall, the proportion of uric acid calculi was markedly higher in patients with rather than without metabolic syndrome (19.6 vs 11.2%; P=0.002). However, the proportion of calcium oxalate, carbonate apatite and struvite calculi did not differ between the two groups. The multivariable-adjusted odds ratio for uric acid calculi according to the metabolic syndrome components indicated that the presence of metabolic syndrome was associated with a 93% increased odds ratio of uric acid calculi compared with the absence of metabolic syndrome. Impaired fasting glucose and hypertriglyceridemia were independent risk factors for uric acid calculi.

CONCLUSIONS

Metabolic syndrome is associated with a significantly increased risk of uric acid calculi development, especially those with impaired fasting glucose and hypertriglyceridemia.

Prevalence of metabolic syndrome and gender differences

In a comparative study, involving 500 subjects with 294 males and 206 females aged 30 years and above, data were collected from NIMS (National Institute of Medical Sciences) hospital and research centre and controls from the general population whose age and sex were matched with subjects during the years 2010 - 2011. Metabolic syndrome was present both in women and men corresponding to 29% and 23% of the women's and men's sample, respectively. The prevalence was higher in women than in men. In women, elevated BMI, low HDL cholesterol, increased waist circumference and hyperglycemia were significantly larger contributors to the metabolic syndrome while in men these were hypertension and elevated triglycerides. The contribution of several metabolic components to the metabolic syndrome is different in men and women. This might contribute to gender specific differences in the relative risk of metabolic complications such as insulin resistance.

Causes of different estimates of the prevalence of metabolic syndrome in Korea

BACKGROUND/AIMS

Reports of the prevalence of and trends in metabolic syndrome in Korea have been inconsistent. Thus, we investigated the reasons underlying these inconsistencies.

METHODS

We estimated the prevalence of metabolic syndrome using different diagnostic criteria, exclusion criteria, and sampling weights among 5,509 respondents, aged 20-79, who participated in the 2001 Korean National Health and Nutrition Examination Surveys (KNHANES). Trends in metabolic syndrome were assessed by examining the 1998 (n = 6,747), 2001 (n = 4,337), and 2005 (n = 5,139) KNHANES.

RESULTS

The estimated prevalence of metabolic syndrome in 2001 ranged from 1.6 to 29.6% in males and from 10.1 to 32.8% in females, depending on the diagnostic criteria used. The exclusion criteria and sampling weights did not significantly affect the prevalence estimates. The prevalence of metabolic syndrome first significantly increased and then decreased between 1998, 2001, and 2005 in males (26.2, 29.6, and 27.2%, respectively) and females (29.2, 32.8, and 24.7%, respectively). Among the individual metabolic variables, triglyceride levels in 2001 were significantly higher than in 1998 and 2005, whereas other variables remained relatively constant during the same period. The exceptionally high triglyceride levels in 2001 might have contributed to the increased prevalence of metabolic syndrome between 1998 and 2001.

CONCLUSIONS

Different diagnostic criteria for metabolic syndrome represent a major cause of the inconsistent estimates of prevalence, and the absence of standardized laboratory methods might have affected the trend estimates.

The relationship between insulin-like growth factor-1 and metabolic syndrome, independent of adiponectin

BACKGROUND

Insulin-like growth factor-1 (IGF-1) is associated with obesity and aging, and was recently linked to metabolic syndrome (MetS) and insulin resistance. However, little is known about the relationship between IGF-1 and adiponectin (adiponectin), another marker of MetS.

METHODS

We measured the plasma IGF-1 and adiponectin levels of 3099 subjects (1869 males, 55.9±10.8 y). We applied the Korean-modified International Diabetes Foundation (k-IDF) criteria for determination of, and risk assessment for, MetS.

RESULTS

K-IDF criteria-based MetS occurred in 37.0% (n=1146) of patients. IGF-1 (91.5 vs. 97.3 ng/ml, p<0.001) and adiponectin (3.95 vs. 4.23 μg/ml, p<0.001) were significantly lower in MetS patients than without MetS. Lower IGF-1 was associated with increasing numbers of MetS abnormalities, independent of adiponectin (p for trend<0.001, F=12.615, p<0.001 in ANCOVA). MetS prevalence in individuals with both high IGF-1 and adiponectin levels (6.7%, n=206) was significantly lower than in other groups. Both high IGF-1 and adiponectin group was associated with reduced MetS risk after adjusting for other confounding factors (OR 0.694, 95% CI 0.493-0.977, p=0.036).

CONCLUSIONS

IGF-1 was associated with MetS independent of adiponectin in our study. The independent relationship between IGF-1 and MetS provides insight into the pathophysiologic mechanisms of MetS.

Men's health in South Korea

Over the last four decades, rapid industrialisation and a Westernized lifestyle have changed disease patterns in South Korea. This study was conducted to review the current state of men's health in South Korea. By reviewing reports of government authorities and domestic and foreign studies related to men's health, we found that in men ≥ 65 years of age, 28.4% considered their health status good, whereas 38.3% considered their health status poor. The prevalence of moderate-to-severe lower urinary tract symptoms was similar to that in Caucasians. The prevalence of erectile dysfunction was higher than the global average. The incidence of cryptorchidism and hypospadias showed a tendency towards increase. The prevalence of diabetes mellitus continuously increased by 10.8% in 2008 and was the fifth leading cause of death in 2008. The prevalence of obesity increased from 26.0% in 1998 to 31.7% in 2007. The prevalence of ischaemic heart disease has continuously increased, with heart diseases causing one of every 12 deaths. The prevalence of chronic obstructive pulmonary disease in 2005 was 17.2% among adults ≥ 45 years of age. The top five prevalent cancers in men, in descending order, were cancers of the stomach, lung, liver, large bowel and prostate, among which the incidence of stomach, lung and liver cancers decreased by 0.7%, 0.6% and 2.2%, respectively, from 1999 to 2007, whereas the incidence of large bowel and prostate cancers increased by 7.0% and 13.2%, respectively. The prevalence of depression, dementia and sleep disorders was estimated as 17.3%, 4.21% and 20.2%, respectively. Together, these findings suggest that disease patterns in South Korean men are becoming Westernized.

Alanine aminotransferase is associated with metabolic syndrome independently of insulin resistance

BACKGROUND

Few studies have examined the effect of insulin resistance on the association between alanine aminotransferase (ALT) and metabolic syndrome. The association between ALT levels and metabolic syndrome were determined, independently of insulin resistance in Korean populations.

METHODS AND RESULTS

The association between ALT and metabolic syndrome were examined in 28,456 subjects who visited 7 Health Promotion Centers at University Hospitals in Korea from 2006 to 2008. HOMA-IR index was used to represent insulin resistance index. ALT levels were found to be positively associated with metabolic syndrome after adjusting for age, alcohol intake, and smoking status. Furthermore, when additional adjustment was made for insulin resistance, this association between ALT and metabolic syndrome, although slightly attenuated, remained strongly significant. Subjects in the highest ALT quartile were found to have a higher risk of having metabolic syndrome than those in the lowest quartile (odds ratio (OR)=4.45, 95% confidence interval (CI)=3.96-4.99 for men and OR=3.51, 95%CI=2.73-4.52 for women). In addition, the association between ALT level and the risk of metabolic syndrome was significantly higher in the relatively low risk group.

CONCLUSIONS

ALT levels were found to be significantly associated with metabolic syndrome independently of insulin resistance and with an interaction by age. Further cohort studies are needed to determine the usefulness of ALT levels for predicting the risk of metabolic syndrome.

Identification of metabolic syndrome using decision tree analysis

This study employs decision tree as a decision support system for rapid and automated identification of individuals with metabolic syndrome (MS) among a Thai population. Results demonstrated strong predictivity of the decision tree in classification of individuals with and without MS, displaying an overall accuracy in excess of 99%.

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.

The prevalence and clinical characteristics of reflux esophagitis in koreans and its possible relation to metabolic syndrome

The prevalence of reflux esophagitis is increasing in Korea. To estimate the prevalence and clinical characteristics of reflux esophagitis in healthy subjects, we retrospectively examined the medical records of healthy subjects undergoing a routine check-up from October 2004 to September 2005. A total of 6,082 (3,590 men, mean age 44+/-10 yr) subjects were enrolled in this study. The prevalence of reflux esophagitis in healthy subjects was 10.5%. According to the univariate analysis, male sex (odds ratio [OR] 3.49, 95% confidence interval [CI] 2.84-4.30), smoking history (OR 1.91, 95% CI 1.60-2.28), body mass index (BMI) >30 kg/m(2) (OR 2.13, 95% CI 1.37-3.33), total cholesterol >250 mg/dL (OR 1.50, 95% CI 1.05-2.14), low-density lipoprotein (LDL) cholesterol >/=160 mg/dL (OR 1.52, 95% CI 1.08-2.14), triglyceride >/=150 mg/dL (OR 1.92, 95% CI 1.61-2.30), high blood pressure (BP) (OR 1.46, 95% CI 1.20-1.76), and fasting glucose >/=110 mg/dL (OR 1.45, 95% CI 1.13-1.86) were significantly associated with reflux esophagitis (all p<0.05). However, age, alcohol drinking and Helicobacter pylori infection were not associated with reflux esophagitis. In conclusion, significant relationships of reflux esophagitis with obesity, low high-density lipoprotein (HDL) cholesterol, high triglyceride, high BP, and elevated fasting glucose suggested that reflux esophagitis might represent the disease spectrum of the metabolic syndrome.

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.

Prevalence of metabolic syndrome compared between native Japanese and Japanese-Americans

Metabolic syndrome is a condition characterized by the accumulation of multiple risk factors for atherosclerosis. Japanese-Americans in the U.S. have a more rapid and intense progression of atherosclerosis than native Japanese in Japan due to a westernization of their lifestyle. We investigated the prevalence of metabolic syndrome between 416 native Japanese (194 men and 222 women) in Hiroshima and 574 Japanese-Americans (217 men and 357 women) in Los Angeles, aged 30-89 years. According to the criteria proposed by the Japanese Society of Internal Medicine, the prevalence was 13.9 and 2.7% for native Japanese men and women, and 32.7 and 3.4% for Japanese-American men and women, respectively. According to the IDF or AHA/NHLBI criteria, the prevalence was 20.1 and 6.3%, and 38.7 and 4.5%, or 13.4 and 14.4%, and 30.9 and 27.7%, respectively. Thus, the prevalence of metabolic syndrome in men was significantly higher in Japanese-American than in native Japanese by all the three criteria. However, the prevalence in women was similar between native Japanese and Japanese-American by the Japanese and IDF criteria, whereas it was significantly higher in Japanese-American than in native Japanese by the AHA/NHLBI criteria. This report demonstrates that a westernization of lifestyle can increase the prevalence of metabolic syndrome among Japanese-Americans as compared to native Japanese.

Prevalence of metabolic syndrome in Iranian adult population, concordance between the IDF with the ATPIII and the WHO definitions

BACKGROUND

Different criteria have been proposed by the WHO, the ATPIII and the International Diabetes Federation (IDF) for the diagnosis of the metabolic syndrome (MES). The objective of this study was to estimate the prevalence of this syndrome using the IDF definition among Iranian adults and to compare it with the prevalence estimated using the two other definitions.

MATERIALS AND METHODS

The prevalence of the MES was determined according to the three different proposals in 10,368 men and women aged >/=20 years participated in the cross-sectional phase of the Tehran Lipid and Glucose Study. To assess the degree of agreement between different MES definitions, the k test was used.

RESULTS

The prevalence of MES (95% confidence interval) was 32.1% (31.2-33.0) by the IDF definition, 33.2% (32.3-34.1) by the ATPIII and 18.4% (17.6-19.2) according to the WHO definition. The sensitivity, specificity of the IDF definition for detecting MES were 91%, 89% for the ATPIII and 73%, 77% for the WHO definition, respectively. The k statistics for the agreement of the IDF definition was 66.3+/-0.01 with the ATPIII and 39.5+/-0.01 with the WHO definition.

CONCLUSION

In the Iranian population, the IDF definition for MES has a good concordance with the ATP III definition and a low concordance with the WHO definition.

Prevalence of the metabolic syndrome among Korean adults using the new International Diabetes Federation definition and the new abdominal obesity criteria for the Korean people

This study was performed to compare the prevalence of the metabolic syndrome according to the International Diabetes Federation (IDF) and National Cholesterol Education Program (NCEP) definitions, and abdominal obesity criteria of WHO and the Korean Society for the Study of Obesity (KSSO) in Korean adults. A total of 4452 adults aged > or =20 years from the Korean National Health and Nutrition Examination Survey 2001 were analyzed. The prevalence of the metabolic syndrome estimated by NCEP definition with WHO criteria, NCEP with KSSO, IDF with WHO, and IDF with KSSO were 26.7%, 23.7%, 23.8% and 17.5%, respectively. The agreement percent among the four definitions ranged from 88.7% to 100% in men, and from 85.6% to 94.9% in women. The NCEP-defined metabolic syndrome was more strongly associated with hypertension and diabetes than the IDF-defined metabolic syndrome (age-adjusted odds ratio: 5.1 versus 3.6 for hypertension and 6.4 versus 3.2 for diabetes in men, respectively; 5.4 versus 3.4-4.3 for hypertension and 11.1 versus 3.8-4.2 for diabetes in women, respectively). Both definitions of the metabolic syndrome were associated with coronary heart disease or stroke only in women. Prospective studies are warranted to evaluate the predictive ability of the new definition of the metabolic syndrome and the new criteria of abdominal obesity for cardiovascular morbidity and mortality in Korean adults.

How should we manage patients with non-alcoholic fatty liver disease in 2007?

Evidence-based management guidelines for non-alcoholic fatty liver disease (NAFLD) are lacking in the Asia-Pacific region or elsewhere. This review reports the results of a systematic literature search and expert opinions. The Asia-Pacific Working Party on NAFLD (APWP-NAFLD) has generated practical recommendations on management of NAFLD in this region. NAFLD should be suspected when there are metabolic risk factors and/or characteristic changes on hepatic ultrasonography. Diagnosis by ultrasonography, assessment of liver function and complications, exclusion of other liver diseases and screening for metabolic syndrome comprise initial assessment. Liver biopsy should be considered when there is diagnostic uncertainty, for patients at risk of advanced fibrosis, for those enrolled in clinical trials and at laparoscopy for another purpose. Lifestyle measures such as dietary restrictions and increased physical activity (aerobic exercise) should be encouraged, although the best management strategy to achieve this has yet to be defined. Complications of metabolic syndrome should be screened for regularly. Use of statins to treat hypercholesterolemia is safe and recommended; frequent alanine aminotransferase (ALT) monitoring is not required. Obese patients who do not respond to lifestyle measures should be referred to centers specializing in obesity management; consideration should be given to bariatric surgery or gastric ballooning. The role of pharmacotherapy remains investigational and is not recommended for routine clinical practice. Non-alcoholic fatty liver disease should be recognized as part of the metabolic syndrome and managed in a multidisciplinary approach that addresses liver disease in the context of risk factors for diabetes and premature cardiovascular disease. Lifestyle changes are the first line and mainstay of management.

What are the risk factors and settings for non-alcoholic fatty liver disease in Asia-Pacific?

The risk factors and settings for non-alcoholic fatty liver disease (NAFLD) in Asians are reviewed comprehensively. Based particularly on large community-based studies using ultrasonography, case-control series and prospective longitudinal studies, the prevalence of NAFLD in Asia is between 12% and 24%, depending on age, gender, locality and ethnicity. Further, the prevalence in China and Japan has nearly doubled in the last 10-15 years. A detailed analysis of these data shows that NAFLD risk factors for Asians resemble those in the West for age at presentation, prevalence of type 2 diabetes mellitus (T2DM) and hyperlipidemia. The apparent differences in prevalence of central obesity and overall obesity are related to criteria used to define waist circumference and body mass index (BMI), respectively. The strongest associations are with components of the metabolic syndrome, particularly the combined presence of central obesity and obesity. Non-alcoholic fatty liver disease appears to be associated with long-standing insulin resistance and likely represents the hepatic manifestation of metabolic syndrome. Not surprisingly therefore, Asians with NAFLD are at high risk of developing diabetes and cardiovascular disease. Conversely, metabolic syndrome may precede the diagnosis of NAFLD. The increasing prevalence of obesity, coupled with T2DM, dyslipidemia, hypertension and ultimately metabolic syndrome puts more than half the world's population at risk of developing NAFLD/non-alcoholic steatohepatitis/cirrhosis in the coming decades. Public health initiatives are clearly imperative to halt or reverse the global 'diabesity' pandemic, the underlying basis of NAFLD and metabolic syndrome. In addition, a perspective of NAFLD beyond its hepatic consequences is now warranted; this needs to be considered in relation to management guidelines for affected individuals.

Metabolic syndrome, or What you will: definitions and epidemiology

The metabolic syndrome is a clustering of risk factors which predispose an individual to cardiovascular morbidity and mortality. There is general consensus regarding the main components of the syndrome (glucose intolerance, obesity, raised blood pressure and dyslipidaemia [elevated triglycerides, low levels of high-density lipoprotein cholesterol]) but different definitions require different cut points and have different mandatory inclusion criteria. Although insulin resistance is considered a major pathological influence, only the World Health Organization (WHO) and European Group for the study of Insulin Resistance (EGIR) definitions include it amongst the diagnostic criteria and only the International Diabetes Federation (IDF) definition has waist circumference as a mandatory component. The prevalence of metabolic syndrome within individual cohorts varies with the definition used. Within each definition, the prevalence of metabolic syndrome increases with age and varies with gender and ethnicity. There is a lack of diagnostic concordance between different definitions. Only about 30% of people could be given the diagnosis of metabolic syndrome using most definitions, and about 3540% of people diagnosed with metabolic syndrome are only classified as such using one definition. There is currently debate regarding the validity of the term metabolic syndrome, but the presence of one cardiovascular risk factor should raise suspicion that additional risk factors may also be present and encourage investigation. Individual risk factors should be treated.