Optimal waist circumference cutoff values for the diagnosis of abdominal obesity in korean adults

Relationship between perception of body image on obesity and smoking status by age group in women: Findings of a seven-year Korean National Survey

INTRODUCTION

This descriptive study examined the relationship between body image perception and smoking status among women aged 19-64 years in Korea, using data from the Korea National Health and Nutrition Examination Survey (KNHANES).

METHODS

This study is a secondary analysis of data gathered from the KNHANES between 2014 and 2020, encompassing 12515 women aged 19-64 years. The final study group consisted of 742 current smokers (CS), 132 hidden smokers (HS), and 11641 non-smokers (NS). Hidden smokers were defined as participants who reported being non-smokers but had urine cotinine levels >50 ng/mL. The participants were divided into three age categories: 19-29, 30-49, and 50-64 years. A multiple logistic regression analysis was used to assess the relationship between body image perception and smoking status, by age group.

RESULTS

Baseline statistics indicated that smokers (both CS and HS) generally had a lower socioeconomic status across all age groups. The highest rate of obesity perception was observed in the CS group, followed by the HS group, in both groups of women aged 19-29 and 30-49 years. However, only women aged 19-29 years in the CS group were more likely to perceive themselves as obese than those in the NS group (AOR=2.60; 95% CI: 1.49-4.52; p=0.001). Furthermore, factors such as current smoking status (AOR=2.32; 95% CI: 1.28-4.23; p=0.006), higher body mass index (AOR=2.95; 95% CI: 2.59-3.37; p<0.001), and perceived health status as poor (AOR=3.82; 95% CI: 2.11-6.92; p<0.001), significantly influenced the perception of obesity in this age group.

CONCLUSIONS

This study identified a notable relationship between obesity perception and smoking among women aged 19-29 years only. These findings suggest that interventions aimed at weight reduction or modifying the perception of obesity, could potentially aid smoking cessation efforts in young women.

The positive impact of smoking cessation on fracture risk in a nationwide cohort study

Many studies sought to demonstrate the association between smoking and fracture risk. However, the correlation between smoking and fractures remains controversial. This study aimed to examine the impact of smoking and smoking cessation on the occurrence of fractures using prospective nationwide cohort data. We enrolled those who underwent a National Health Insurance Service (NHIS) health checkup in 2009-2010 who had a previous health checkup 4-year prior (2005-2006). The study population of 4,028,559 subjects was classified into three groups (non-smoker, smoking cessation, current smoker). The study population was also analyzed according to fracture type (all fractures, vertebral fracture, hip fracture). Lastly, the smoking cessation group and current smoker group were divided into four subgroups based on a lifetime smoking amount cut-off of 20 pack-years (PY). Multivariate-adjusted hazard ratios (HRs) of fracture were examined through a Cox proportional hazards model. After multivariable adjustment, non-smokers showed the lowest risk of fracture (HR = 0.818, CI 0.807-0.828, p < 0.0001) and smoking cessation significantly lowered the risk of fracture (HR 0.938, 95% CI 0.917-0.959, p < 0.0001) compared to current smokers. Regardless of 20PY, all smoking cessation subgroups showed significantly less risk of fractures than current smokers with ≥ 20PYs. Smoking increases the risk of fracture, and smoking cessation lowers the risk of fracture.

Association between waist circumference change after smoking cessation and incidence of hypertension in Korean adults

OBJECTIVES

This study investigates the association between smoking cessation and hypertension incidence, as well as the association between waist circumference change after smoking cessation and hypertension incidence.

STUDY DESIGN

This was a nationwide population-based cohort study.

METHODS

We used the Korean Health Screening Cohort data and included 158,505 participants who had undergone two or more health examinations between 2008 and 2011, with follow-ups throughout 2019. Smoking cessation and waist changes were captured based on difference between first and follow-up screening dates. Hazard ratio (HR) and 95% confidence interval (CI) for hypertension risk were estimated using multivariable Cox proportional hazard regression models.

RESULTS

There were 31,270 cases of hypertension during a median follow-up of 8.50 years. After adjusting for potential confounding factors, HR for hypertension were 1.01 (95% CI: 0.97-1.05), 0.91 (95% CI: 0.87-0.95), and 0.88 (95% CI: 0.85-0.91) for recent quitters, long-term quitters, and non-smokers, respectively, compared with current smokers. HR for hypertension, compared with current smokers, were 0.89 (95% CI: 0.84-0.94), 0.91 (95% CI: 0.85-0.97), and 0.99 (95% CI: 0.91-1.08) for long-term quitters with no waist gain, long-term quitters with waist gain of 0.1-5.0 cm, and long-term quitters with waist gain of ≥5.0 cm, respectively.

CONCLUSIONS

Long-term smoking cessation was significantly associated with decreased risk of hypertension, and long-term smoking cessation with no waist gain or less than 5.0 cm of waist gain was significantly associated with decreased risk of hypertension. However, more than 5.0 cm of waist gain can attenuate the effect of long-term smoking cessation on lowering the risk of hypertension.

Machine learning analysis for the association between breast feeding and metabolic syndrome in women

This cross-sectional study aimed to develop and validate population-based machine learning models for examining the association between breastfeeding and metabolic syndrome in women. The artificial neural network, the decision tree, logistic regression, the Naïve Bayes, the random forest and the support vector machine were developed and validated to predict metabolic syndrome in women. Data came from 30,204 women, who aged 20 years or more and participated in the Korean National Health and Nutrition Examination Surveys 2010-2019. The dependent variable was metabolic syndrome. The 86 independent variables included demographic/socioeconomic determinants, cardiovascular disease, breastfeeding duration and other medical/obstetric information. The random forest had the best performance in terms of the area under the receiver-operating-characteristic curve, e.g., 90.7%. According to random forest variable importance, the top predictors of metabolic syndrome included body mass index (0.1032), medication for hypertension (0.0552), hypertension (0.0499), cardiovascular disease (0.0453), age (0.0437) and breastfeeding duration (0.0191). Breastfeeding duration is a major predictor of metabolic syndrome for women together with body mass index, diagnosis and medication for hypertension, cardiovascular disease and age.

The prevalence and factors associated with sarcopenia in Thai older adults: A systematic review and meta-analysis

Objective

This systematic review and meta-analysis aimed to assess the prevalence and identify factors associated with sarcopenia in older Thais.

Methods

Research studies were searched in online databases, including PubMed, Embase, Scopus, and Thai-Journal Citation Index. The articles included in this review were limited to being published between January 1, 2013 and January 31, 2023 and observational study designs. The research quality was evaluated using the Joanna Briggs Institute (JBI) critical appraisal tool for prevalence studies. A meta-analysis was performed using the JBI SUMARI software. The review protocol has been registered on PROSPERO with the assigned ID CRD42023420514.

Results

A total of 265 research articles were initially identified, out of which 17 articles were included in this study, including a total of 4,668 participants aged 60 years and over, consisting of 1,380 (29.6%) men and 3,288 (70.4%) women. The overall prevalence of sarcopenia in Thai older adults was 20.7% (95% CI 14.4%-27.8%). Subgroup analysis of the sarcopenia prevalence based on the study areas revealed that the prevalence was 33.4% (95% CI 28.7%-38.3%) in hospitalized individuals, 23.2% (95% CI 12.5%-35.9%) in outpatient clinic settings, and 17.3% (95% CI 9.4%-26.8%) in community-living older adults. Advanced age (OR = 4.60, 95% CI 3.07-6.91), being male (OR = 2.30, 95% CI 1.37-3.85), low body mass index (BMI) (OR = 8.95, 95% CI 6.05-13.25), and malnutrition (OR = 2.78, 95% CI 2.09-3.70) are strong predictors of sarcopenia in older adults in Thailand.

Conclusions

This systematic review represents the first assessment of the overall prevalence and factors associated with sarcopenia in Thai older adults, indicating its significant concern within this population. These findings are of importance for public health management aimed at preventing and managing sarcopenia in the country.

Body Composition and Cardiovascular Risk: A Study of Polish Military Flying Personnel

(1) Background: Military personnel worldwide exhibit high rates of obesity. Obesity, and especially visceral obesity, contribute to various health issues, including type 2 diabetes and cardiovascular diseases (CVD). While BMI is commonly used to diagnose obesity, it has limitations and does not consider factors like fat distribution or muscle mass. This study aims to assess the relationship between BMI, percent body fat, waist circumference (WC), waist-to-height ratio (WHtR), and cardiovascular risk factors in Polish military flying personnel. Methods: This study involved 200 men from the Polish Air Force aged 38.8 ± 8.5 years. Anthropometric tests, body composition tests, and tests of biochemical markers of CVD were conducted. (2) Results: The prevalence of overweight and obesity varied based on the evaluation criterion; they were present in 63.5% of soldiers by BMI and in 52.5% by percent body fat; abdominal obesity was present in almost half (47%) of the surveyed soldiers according to WC and in 62.5% according to WHtR. All markers of obesity correlated positively with various biochemical markers of CVD, and 8.5% of subjects met the criteria for metabolic syndrome. (3) Conclusions: The prevalence of obesity in Polish military flying personnel, regardless of the evaluation criterion, is associated with significant metabolic complications in the form of lipid disorders and insulin resistance.

Sleep Quality in Women with Premenstrual Syndrome Is Associated with Metabolic Syndrome-Related Variables

In this study, we examined whether metabolic syndrome (MetS)-related variables are simultaneously affected by sleep quality, premenstrual syndrome (PMS) and dietary consumption. In this cross-sectional study, data for 307 premenopausal women were available. The results showed that women experiencing PMS had significantly lower sleep quality and were more depressed and anxious (p < 0.001 for all). After the subjects were divided into groups according to PMS, the effect of sleep quality on MetS-related variables or MetS components significantly differed; only among women who experienced PMS were poor sleepers significantly higher in waist circumference (p = 0.018) and diastolic blood pressure (p = 0.012) than good sleepers. Among the MetS components, abdominal obesity in women with poor sleep quality was approximately three (16.9% vs. 3.0%, p= 0.020) times more common than in those with good sleep quality. However, these findings were not observed among those who did not experience PMS. Poor sleepers among women experiencing PMS consumed 2.8 times more alcoholic drinks than good sleepers (p = 0.006). The MetS-related variables in Korean women experiencing PMS are associated with sleep quality, and these associations may be modified by dietary habits.

Waist circumference and end-stage renal disease based on glycaemic status: National Health Insurance Service data 2009-2018

BACKGROUND

Obesity is associated with an increased risk of developing type 2 diabetes mellitus (T2DM) and end-stage renal disease (ESRD). This study aimed to examine the effect of waist circumference (WC) on the risk for ESRD based on glycaemic status in a Korean population-based sample.

METHODS

This cohort study with a 9.2-year follow-up period used a population-based National Health Insurance Service health checkup database with approximately 10 585 852 participants who were followed up from 2009 to the time of ESRD diagnosis. WC was categorized into seven levels in 5-cm increments, with Level 4 as the reference group. Glycaemic status was categorized into the following groups: normal fasting glucose (NFG), impaired fasting glucose (IFG), newly diagnosed T2DM, T2DM treated with ≤2 oral hypoglycaemic agents (OHAs) and diabetes treated with ≥3 OHAs or insulin. We calculated hazard ratios (HRs) and 95% confidence intervals (CIs) for ESRD according to WC values and glycaemic status of the participants.

RESULTS

The study finally included 10 177 245 patients with a mean age of 47.1 (13.8) years. The study population included 5 604 446 men (55.1%) and 4 572 799 women (45.9%). In total, 8.3% (n = 877 143) of the study population had diabetes. During the mean follow-up of 9.2 (1.0) years (93 554 951 person-years of follow-up), 23 031 individuals were newly diagnosed with ESRD. The ESRD risk increased in parallel with an increase in WC in participants without T2DM, that is, the NFG and IFG groups (adjusted HRs [95% CIs] of WC Levels 4, 5 and 6: 1.17 [1.09-1.26], 1.37 [1.25-1.51] and 1.84 [1.63-2.07] in the NFG group and 1.06 [0.97-1.16], 1.23 [1.10-1.38] and 1.80 [1.57-2.06] in the IFG group, respectively). In patients with T2DM, the risk for ESRD was significantly increased in those with a low WC (adjusted HRs [95% CIs] of WC Level 1: 2.23 [1.77-2.80], 3.18 [2.70-3.74] and 10.31 [9.18-11.59] in patients with newly diagnosed diabetes, patients on ≤2 OHAs and those on ≥3 OHAs or insulin, respectively). The association between WC and ESRD thus showed a J-shaped pattern in patients with newly diagnosed T2DM and a U-shaped pattern in those on ≤2 OHAs and on ≥3 OHAs or insulin.

CONCLUSIONS

Central obesity substantially increases the risk of developing ESRD regardless of glycaemic status. The harmful effects of low WC only become significant with the progression of T2DM.

Simple anthropometric measures to predict visceral adipose tissue area in middle-aged Indonesian men

The diagnosing of central obesity requires ethnic-specific cut-offs of waist circumference (WC) and body mass index (BMI). This study aims to develop formulas to predict visceral adipose tissue (VAT) area based on WC and BMI to determine the cut-off points of central obesity in Indonesia. We conducted a cross-sectional study among 32 middle-aged Indonesian men. VAT area was measured using an abdominal CT scan, whereas WC and BMI were assessed through anthropometric measurements. Linear regression analysis was performed to define the formulas to predict VAT area using WC and BMI. Next, the optimal cut-off values of WC and BMI were determined using ROC curve analysis. Strong positive correlations were found between WC and VAT as well as BMI and VAT (r = 0.78; r = 0.67, p <0.001). The formula to predict VAT area from WC was -182.65 + (3.35 × WC), whereas the formula to predict VAT area from BMI was -57.22 + (6.95 × BMI). These formulas predicted WC of 88.5 cm and BMI of 23.9 kg/m2 as the optimal cut-off values for central obesity in middle-aged Indonesian men.

Association of high body mass index, waist circumference, and body fat percentage with sarcopenia in older women

BACKGROUND

Age-related obesity and body composition changes include loss of muscle mass and increased body fat. This study aimed to investigate sex differences in the impact of sarcopenia, defined by the Asian Working Group for Sarcopenia (AWGS), on obesity in Korean older adults.

METHODS

In this 2-year longitudinal study, 3014 participants were excluded based on AWGS sarcopenia parameters (if any one of the sarcopenic parameter criteria was satisfied), including low handgrip strength (HGS), low appendicular skeletal muscle mass index (ASMI), and low short physical performance battery (SPPB). A total of 926 non-sarcopenic participants were recruited for the study. The obese and non-obese groups were compared according to the sarcopenia parameters. The following variables were selected for obesity analysis: body mass index (BMI), waist circumference (WC), and body fat percentage. Unadjusted and fully adjusted logistic regression analyses were performed for each variable to predict sarcopenia and sarcopenic obesity according to sex.

RESULTS

Among the sarcopenia parameters, reduction in ASMI was significantly lower in the obese group with high WC and percentage of body fat (PBF) in both men and women (P < 0.01). Multivariable analysis revealed that different obesity parameters were associated with AWGS criteria: women in the high BMI group presented significantly lower ASMI and sarcopenia (ASMI, OR = 0.289, 95% CI = 0.174-0.480; sarcopenia, OR = 0.152, 95% CI = 0.048-0.483). Women in the high WC group had significantly lower ASMI and sarcopenia (ASMI, OR = 0.307, 95% CI = 0.189-0.500; sarcopenia, OR = 0.262, 95% CI = 0.106-0.649). Women in the high PBF group had a lower incidence of sarcopenia (OR = 0.214, 95% CI = 0.068-0.278).

CONCLUSIONS

Our study identified that high BMI had a protective effect on the reduction of muscle mass in men and women. However, obesity parameters including BMI, WC, and PBF were positively correlated with a lower incidence of sarcopenia only in women. Obesity in older women may have a protective effect in reducing ASMI and the incidence of sarcopenia.

Risk of Carotid Atherosclerosis in Subjects with Prediabetes Overlapping Metabolic Syndrome

Background: While the number of individuals with prediabetes and metabolic syndrome (MetS) is increasing, only a few studies have reported differences in cardiovascular risk according to the presence or absence of MetS in individuals with prediabetes. Here, we examined differences in carotid intima-media thickness (CIMT) and carotid plaques in individuals with prediabetes with or without MetS among subjects who visited a single center in Seoul (Huh Diabetes Center). Methods: A total of 328 participants aged ≥20 years, including the group with normoglycemia, were enrolled in the analysis, of which 273 had prediabetes. Individuals with prediabetes were defined as those who met one or more of the following two criteria: fasting plasma glucose of 100-125 mg/dL and/or HbA1c level of 5.7%-6.4%. Carotid atherosclerosis was determined by mean and maximal CIMT and by the presence of carotid plaques. Results: Eighty-nine subjects (32.6% of prediabetes group) were categorized as having MetS. Those with MetS had significantly higher mean CIMT and maximal CIMT than those without (P < 0.05). Moreover, the group with MetS had a significantly higher prevalence of carotid plaques than the group without MetS [odds ratio (OR): 2.45, 95% confidence interval (CI): 1.43-4.19; P = 0.001]. After adjusting for age, sex, body mass index, and low-density lipoprotein cholesterol, individuals with MetS still had greater mean and maximal CIMT than individuals without MetS (P < 0.05), and the presence of MetS was significantly associated with a higher risk of carotid plaques (OR: 2.55, 95% CI: 1.06-6.15; P = 0.037). Conclusion: These results suggest that MetS is independently associated with increased CIMT and the presence of carotid plaques in prediabetes. Our study indicates that the risk of cardiovascular disease (CVD) is high in prediabetic individuals with MetS, and that more attention is needed on the risk of CVD in these individuals.

Synergistic Interaction between Hyperuricemia and Abdominal Obesity as a Risk Factor for Metabolic Syndrome Components in Korean Population

BACKGROUND

The present study investigated the role of synergistic interaction between hyperuricemia and abdominal obesity as a risk factor for the components of metabolic syndrome.

METHODS

We performed a cross-sectional study using the data of 16,094 individuals from the seventh Korean National Health and Nutrition Examination Survey (2016 to 2018). The adjusted odds ratios of metabolic syndrome and its components were analyzed by multivariate logistic regression analysis. The presence of synergistic interaction between hyperuricemia and abdominal obesity was evaluated by calculating the additive scales-the relative excess risk due to interaction, attributable proportion due to interaction, and synergy index (SI).

RESULTS

There was a synergistic interaction between hyperuricemia and abdominal obesity in hypertriglyceridemia (men: SI, 1.39; 95% confidence interval [CI], 1.01 to 1.98; women: SI, 1.61; 95% CI, 1.02 to 2.69), and low high-density lipoprotein cholesterol (HDL-C) (men: SI, 2.03; 95% CI, 1.41 to 2.91; women: SI, 1.70; 95% CI, 1.05 to 2.95). There was no significant synergistic interaction between hyperuricemia and abdominal obesity for the risk of high blood pressure (men: SI, 1.22; 95% CI, 0.85 to 1.77; women: SI, 1.53; 95% CI, 0.79 to 2.97), and hyperglycemia (men: SI, 1.03; 95% CI, 0.72 to 1.47; women: SI, 1.39; 95% CI, 0.75 to 2.57).

CONCLUSION

Hyperuricemia and abdominal obesity synergistically increased the risk of hypertriglyceridemia and low HDL-C in both sexes.

Relation of Dietary n-3 and n-6 Fatty Acid Intakes to Metabolic Syndrome in Middle-Aged People Depending on the Level of HbA1c: A Review of National Health and Nutrition Survey Data from 2014 to 2016

Background and Objectives: The relation of dietary n-6 fatty acid to metabolic syndrome has not been examined and clearly defined. To improve health in the general population, this study was to investigate the role of n-3 and n-6 fatty acids in the reduction in metabolic syndrome and to observe changes in the effects of these fatty acids depending on the level of insulin resistance. Materials and Methods: This cross-sectional study utilized national health and nutrition survey data from 2014 to 2016. From the data, a relation of n-3 and n-6 fatty acid intakes to metabolic syndrome and Hemoglobin A1c (HbA1c)’s role in the relation was evaluated and analyzed for 4852 patients between 40 and 64 years old. Intake frequency of 112 nutrition and daily consumption amounts were identified, and intakes of n-3 and n-4 fatty acids were calculated from this data. Metabolic syndrome was determined for each participant using diagnostic standards for the Asian population published by the National Cholesterol Education Program. Results: Among the total 4852 subjects, 1583 (32.6%) had metabolic syndrome; 736 of 1875 (39.3%) males and 847 of 2977 (28.5%) females had the syndrome. In males, when their HbA1c was low (<5.4%), intakes of both n-3 and n-6 fatty acids were related to a 43−63% decreased prevalence of metabolic syndrome with significance, and a similar negative tendency was also observed in females. On the contrary, for both males and females, no statistically significant correlation was present when HbA1c was high. Conclusion: It was considered that consistent and regular dietary intakes of n-3 and n-6 fatty acids may contribute greatly to prevent or treat metabolic syndrome in healthy males with normal insulin sensitivity, but the effect of their dietary intakes was found to be limited in a group with strong insulin resistance. The conclusion of this study presents a valuable reference and knowledge to provide nutritional education to the general population.

A Longitudinal Retrospective Observational Study on Obesity Indicators and the Risk of Impaired Fasting Glucose in Pre- and Postmenopausal Women

The impact of obesity could differ according to menopausal status since women undergo significant physiologic and metabolic changes due to menopause. We investigated the association between various major obesity indicators and the risk of impaired fasting glucose (IFG) according to menopausal status using nationally representative data. A total of 571,286 premenopausal and 519,561 postmenopausal women who underwent both Korean National Health Insurance Service (NHIS) cancer screening in 2009 and health check-ups in 2017 were analyzed. Multivariate logistic regression analyses were used to assess the effect of independent variables of body mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR) in 2009, on dependent variable IFG in 2017. After adjusting for potential confounders, the adjusted odds ratios (ORs) and 95% confidence intervals (CIs) of developing IFG were analyzed. In the premenopausal group, the OR of obese BMI (≥25 kg/m2, <30 kg/m2) women was increased to 2.228 (95% CI: 2.139−2.321) compared to the normal BMI (≥18.5, <23 kg/m2) women as a reference. In the postmenopausal group, there was also a higher OR of 1.778 (95% CI: 1.715−1.843) in the obese BMI women compared to the normal group. A similar association of increasing ORs for IFG was shown in both groups when stratified by WC and WHtR. This nationwide study revealed that obesity and abdominal obesity, defined by various obesity indicators, consistently increased odds of acquiring IFG after 8 years in both pre- and postmenopausal groups, with the association being more robust in the premenopausal group. Our findings suggest that weight management and lifestyle modification may require more attention in premenopausal women.

The association of obesity with thyroid carcinoma risk

Background

The prevalence of obesity and an increased incidence of thyroid carcinoma (TC) threaten public health in parallel on a global scale. Sufficient evidence supports excess body fatness in thyroid carcinogenesis, and the role and anthropometric markers of obesity have been causally associated with the rising risk of TC.

Methods

A literature search was conducted in PubMed. Studies focused on the effect of obesity in TC.

Results

This review mainly discusses the global incidence and prevalence of obesity‐related TC. We also review the role of obesity in TC and potential clinical strategies for obesity‐related TC.

Conclusions

Excess body fatness in early life and TC survival initiate adverse effects later in life.

The incidence of thyroid cancer has been increasing in the last decades all over the world. Such a steady growth cannot be entirely attributable to more sensitive diagnostic procedures. Obesity has increased with sufficient rapidity in the same time frame and may as possible promoters and modifiable risk factors for thyroid cancer in recent years. The aim of this review was to focus on the relationship between obesity and the risk of thyroid cancer. Obesity seems to play a relevant role in thyroid cancer carcinogenesis as well as in its severity and aggressiveness. The possible underlying mechanism is involved chronic inflammation mediated by cytokines, leptin, and adiponectins.

Association of Metabolic Health and Central Obesity With the Risk of Thyroid Cancer: Data from the Korean Genome and Epidemiology Study

BACKGROUND

It is unknown whether the risk of thyroid cancer differs among metabolically healthy/unhealthy, normal-weight, or obese women. We aimed to assess the association of metabolic health and obesity with thyroid cancer risk.

METHODS

The Korean Genome and Epidemiology Study is a population-based prospective cohort study. Data were obtained from 173,343 participants (age {greater than or equal to}40 years) enrolled from 2004 to 2013. Obese participants were those with body mass index (BMI) {greater than or equal to}25 kg/m2. Participants with abnormalities in three of these indices were considered metabolically unhealthy: triglycerides, blood pressure, high-density lipoprotein cholesterol (HDL-cholesterol), waist circumference (WC), and fasting glucose levels. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for thyroid cancer risk associated with metabolic health and obesity.

RESULTS

Compared to non-obese women without metabolic abnormalities, metabolically unhealthy women, either normal-weight or obese, had an increased risk of thyroid cancer (HR [95% CI]=1.57[1.02-2.40] and 1.71[1.21-2.41], respectively). Significant association was not observed in men. Thyroid cancer risk was higher among non-obese women with high WC ({greater than or equal to}85 cm; HR [95% CI]=1.62[1.03-2.56]) than in non-obese women with low WC, and in obese women with low HDL-cholesterol (<50 mg/dL; HR[95% CI]=1.75[1.26-2.42]) compared to non-obese women with high HDL-cholesterol.

CONCLUSIONS

Metabolically unhealthy women or women with central adiposity may be at an increased thyroid cancer risk despite normal BMI.

IMPACT

This study suggests that women with central obesity and metabolically abnormality despite normal BMI may constitute a target group for thyroid cancer prevention and control programs.

Relative Lean Body Mass and Waist Circumference for the Identification of Metabolic Syndrome in the Korean General Population

Lean body mass (LBM) comprises organs and muscle, which are the primary determinants of energy expenditure and regulation of glucose and lipid metabolism. Excessive abdominal fat is associated with metabolic abnormality. Little is known about the relationship between metabolic abnormality and LBM and waist circumference (WC), especially in the Asian general population. The aim of this study was to clarify this relationship. We performed a cross-sectional study with 499,648 subjects who received health check-ups at 16 health promotion centers in 13 Korean cities between January 2018 and October 2019. The subjects were categorized into four groups: (a) High (H)-RLBM (relative lean body mass)/Normal (N)-WC, (b) High-RLBM/Abnormal (A)-WC, (c) Low (L)-RLBM/Normal-WC, and (d) Low-RLBM/Abnormal-WC. RLBM was calculated using fat mass data that were estimated via bioelectrical impedance analysis. L-RLBM/A-WC was significantly associated with metabolically unhealthy status (OR: 4.40, 95% CI: 4.326–4.475) compared to H-RLBM/N-WC. L-RLBM/N-WC (OR: 2.170, 95% CI: 2.122–2.218) and H-RLBM/A-WC (OR: 2.713, 95% CI: 2.659–2.769) were also significantly related to metabolic unhealthy status. The cut-offs of RLBM for predicting metabolic syndrome (MetS) were 74.9 in males and 66.4 in females (p < 0.001). L-RLBM and A-WC are associated with metabolic abnormality in the Korean general population. RLBM is an anthropometric index that can be used to predict MetS in primary health care.

No Association between Metabolic Syndrome and Periodontitis in Korean Postmenopausal Women

This study aimed to determine the association between metabolic syndrome (MetS) and periodontitis in Korean postmenopausal women. The study selected 3320 menopause women (40-79-year-old) from those who participated in the seventh Korea National Health and Nutrition Survey (2016-2018). This association was determined using frequency and multiple logistic regression analyses. The prevalence of MetS in postmenopausal women was 33.2%, and among the MetS components, abdominal obesity showed a higher odds ratio of periodontitis by 1.36 (95% confidence interval (CI): 1.12-1.65; p < 0.05). The odds ratio for periodontitis was 1.34 times higher (95% CI: 1.12-1.60) in the MetS prevalence group with three or more MetS components (p < 0.05); however, after adjusting for demographic characteristics and health behavior variables, it was not statistically significant. Therefore, our results indicated that MetS has no association with periodontitis in postmenopausal women after adjusting for confounding variables.

Association between Metabolic Syndrome and the Number of Remaining Teeth in Postmenopausal Women: A Cross-Sectional Analysis Using the Korean National Health and Nutritional Examination Survey

There are very few studies on metabolic syndrome (MetS) and oral health in postmenopausal women. The purpose of this cross-sectional study was to determine the association between MetS and its components and the number of remaining teeth in postmenopausal women in Korea. The study selected 3320 menopausal women (40-79 years old) from those who participated in the seventh Korea National Health and Nutrition Survey (2016-2018). Multiple regression and multiple logistic regression analyses were performed to determine the association between MetS and its components and the number of remaining teeth. According to the multiple regression analysis, the regression coefficient (B) values were -1.62 (p < 0.05), -1.31 (p < 0.05), -1.60 (p < 0.05), and -2.28 (p < 0.05) in the hypertension group, hyperglycemia group, low high-density lipoprotein (HDL) cholesterol group, and MetS prevalence group, respectively. This indicates that the number of remaining teeth was lower in the MetS prevalence group as compared to the non-prevalence groups. As observed in the multiple logistic regression analysis, the odds ratio of the number of remaining teeth (less than 20) was higher in the MetS prevalence group (1.82 (p < 0.05)) as compared to the non-prevalence groups (1.25 (p < 0.05) in the abdominal obesity group, 1.50 (p < 0.05) in the hypertension group, 1.36 (p <0.05) in the hyperglycemia group, and 1.72 (p < 0.05) in the low HDL cholesterol group). Therefore, our results indicate that abdominal obesity, hypertension, diabetes, dyslipidemia, and prevalence of MetS are associated with tooth loss in postmenopausal women.

Individual and Synergistic Relationships of Low Muscle Mass and Low Muscle Function with Depressive Symptoms in Korean Older Adults

This study examined the relationship of low appendicular skeletal muscle mass and low muscle function with depressive symptoms in Korean older adults. Community-dwelling Korean older adults aged 65 years and older (n = 521) participated in this study. Appendicular muscle mass (ASM) and muscle function (MF) scores were assessed using dual-energy X-ray absorptiometry (DXA) scanning and sit-to-stand mean power based on a 30 s chair stand test, respectively. Depressive symptoms were evaluated using the Korean form of the Center for Epidemiologic Studies Depression Scale. Logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) of depressive symptoms according to ASM- and MF-based subgroups; normal ASM/normal MF, low ASM/normal MF, normal ASM/low MF, and low ASM/low MF. The prevalence of depressive symptoms was 21.3% in all patients: 20.7% in women and 21.5% in men. Compared to the normal ASM/normal MF participants (OR = 1), the risk of depressive symptoms rose incrementally in subjects with low ASM/normal MF (OR = 2.963, p = 0.019), normal AMS/low MF (OR = 3.843, p = 0.002), and low ASM/low MF (OR = 7.907, p < 0.001), respectively. The current findings suggest that the coexistence of low ASM and low MF is significantly and independently associated with an increased risk for depressive symptoms, with dynapenia having a stronger relationship.

Impact of age and metabolic syndrome-like components on prostate cancer development: a nationwide population-based cohort study

Background

Because of the contradictory results, more epidemiologic data is needed to determine if metabolic syndrome is a risk factor for developing prostate cancer. This study investigated whether metabolic syndrome-like components affect the incidence of prostate cancer in a Korean population.

Methods

Men over 50 years of age who underwent health examinations in 2009 were followed until December 2015 (n=1,917,430) using National Health Insurance System data. Subjects were divided into three groups according to the number of metabolic syndrome-like components. The predictive accuracy of age for prostate cancer was assessed by the Youden index and multivariate adjusted Cox regression analysis was used to analyze the effect of metabolic syndrome-like components on prostate cancer development.

Results

The risk of prostate cancer increases with age, and the best cutoff age for prostate cancer detection was 62 years (the maximum value of the Youden index). When stratified by the number of metabolic syndrome-like components, the age with the highest Youden index of each group is still 61 or 62 years. In multivariate adjusted Cox regression analysis, there was no statistically significant difference in the incidence rate among the non-component group, the group with 1 or 2 components, and the group with ≥3 components.

Conclusions

The current study found that there was no statistically significant association between metabolic syndrome and prostate cancer development in a Korean population. However, results of this study should be interpreted with consideration due to several limitations including the diversity of definitions of metabolic syndrome components.

Associations between elevated growth differentiation factor-15 and sarcopenia among community-dwelling older adults

BACKGROUND

Growth differentiation factor 15 (GDF-15) is associated with disease progression, mitochondrial dysfunction, and mortality. Elevated GDF-15 level was recently reported to be associated with poorer physical performance in healthy adults. However, the association between serum GDF-15 level and sarcopenia in community-dwelling older adults has not been well characterized.

METHODS

We conducted cross-sectional (n = 929) and two-year prospective analyses (n = 788) among participants aged 70-84 years enrolled in the Korean Frailty and Aging Cohort Study. Participants with an estimated glomerular filtration rate of <60 mL/min/1.73 m 2 were excluded. Appendicular lean mass was measured using dual-energy X-ray absorptiometry. Sarcopenia status was determined according to the Asian Working Group for Sarcopenia-2019 algorithm.

RESULTS

At baseline, 16.6% of the participants had sarcopenia. Median GDF-15 concentration was higher in the sarcopenic group than in the non-sarcopenic group (1221 pg/mL vs. 1019 pg/mL, p<0.001). In the multivariate analysis adjusted for cardiometabolic risk and biological factors, the highest GDF-15 tertile (≥1245 pg/mL) had an increased likelihood of sarcopenia (odds ratio, 1.96; 95% confidence interval, 1.16-3.33) than the lowest tertile (<885 pg/mL). During the two-year follow-up period, 67 (10.1%) individuals without sarcopenia at baseline developed sarcopenia. There were no significant associations between baseline serum GDF-15 levels and incident sarcopenia or its components (all p>0.05).

CONCLUSIONS

Elevated GDF-15 was associated with prevalent sarcopenia but not able to predict incident sarcopenia in the 2-year follow-up. Further studies are needed to explore the pathophysiological roles of GDF-15 in the development of sarcopenia.

Exercise training and burdock root (Arctium lappa L.) extract independently improve abdominal obesity and sex hormones in elderly women with metabolic syndrome

The prevalence of metabolic syndrome (MS) is increasing among the elderly, and new lifestyle-based treatment strategies are warranted. We conducted a randomized, double-blind controlled trial of the effects of aquatic exercise (AE) and/or consumption of burdock root extract (BE) on body composition and serum sex hormones, i.e., testosterone, estradiol, sex hormone-binding globulin (SHBG), and dehydroepiandrosterone-sulfate (DHEA-S) in elderly women with MS. The percentage of abdominal fat was decreased in the AE group. Waist circumference was increased in the control (CON) group, but not in the other groups. SHBG and estradiol levels were enhanced by both AE and BE and correlated with changes in fat-related body composition. DHEA-S levels only increased in the BE group, which was consistent with changes in lean body mass. Testosterone levels decreased in the CON group, which correlated with changes in lean body mass, skeletal muscle mass, body fat, and waist circumference. Our findings suggested that the combined AE/BE intervention exerted no synergistic and/or additive effects on any sex-related outcome measures in elderly women with MS.

Effect of body mass index and abdominal obesity on mortality after percutaneous coronary intervention: a nationwide, population-based study

BACKGROUND/AIMS

We investigated the impact of obesity on the clinical outcomes following percutaneous coronary intervention (PCI).

METHODS

We included South Koreans aged > 20 years who underwent the Korean National Health Screening assessment between 2009 and 2012. Obesity was defined using the body mass index (BMI), according to the World Health Organization's recommendations. Abdominal obesity was defined using the waist circumference (WC), as defined by the Korean Society for Obesity. The odds and hazard ratios in all-cause mortality were calculated after adjustment for multiple covariates. Patients were followed up to the end of 2017.

RESULTS

Among 130,490 subjects who underwent PCI, the mean age negatively correlated with BMI. WC, hypertension, diabetes, dyslipidemia, fasting glucose, total cholesterol, low-density lipoprotein cholesterol, and triglyceride levels correlated with the increased BMI. The mortality rates were higher in the lower BMI and WC groups than the higher BMI and WC groups. The non-obese with abdominal obesity group showed a mortality rate of 2.11 per 1,000 person-years. Obese with no abdominal obesity group had the lowest mortality rate (0.88 per 1,000 person-years). The mortality showed U-shaped curve with a cut-off value of 29 in case of BMI and 78 cm of WC.

CONCLUSION

The mortality showed U-shaped curve and the cut-off value of lowest mortality was 29 in case of BMI and 78 cm of WC. The abdominal obesity may be associated with poor prognosis in Korean patients who underwent PCI.

Association of Early-Life Mental Health With Biomarkers in Midlife and Premature Mortality: Evidence From the 1958 British Birth Cohort

Importance

Early-life mental health is known to be associated with socioeconomic adversity and psychological distress in adulthood, but less is known about potential associations with biomarkers and mortality.

Objective

To investigate the association between early-life mental health trajectories with biomarkers in midlife and premature mortality.

Design, Setting, and Participants

This study used data from the British National Child Development Study, a population-based birth cohort. The initial sample of 17 415 individuals consisted of all infants born in Great Britain in a single week in 1958. Analysis began Feburary 2017 and ended May 2020.

Main Outcomes and Measures

Biomarkers collected at age 44 to 45 years were fibrinogen, C-reactive protein, glycated hemoglobin, high- and low-density lipoprotein cholesterol, forced expiratory volume, blood pressure, and waist-to-hip ratio. Information on all-cause mortality was available up to age 58 years and cause-specific mortality up to age 50 years.

Results

Biomarkers were analyzed from 9377 participants (age, 44-45 years, 4712 female [50.3%]) and mortality data from 15 067 participants (age, 58 years; 7379 female [49.0%]). A 4-group longitudinal typology of early-life conduct problems and affective symptoms was identified: (1) stable low, (2) teacher-identified adolescent onset, (3) moderate, and (4) stable high. Compared with the stable-low group, the stable-high (B, 2.308; 95% CI, 0.213-4.404) and teacher-identified adolescent-onset (B, 2.114; 95% CI, 0.725-3.503) groups had less favorable levels of fibrinogen in middle age. Effect modification was observed by sex (P < .005) such that compared with the stable-low group, differences in high-density lipoprotein and abdominal obesity were only observed in female individuals. The stable-high and teacher-identified adolescent-onset groups had elevated risk for all-cause mortality (hazard ratio, 1.878; 95% CI, 1.501-2.350 and hazard ratio, 1.412; 95% CI, 1.174-1.698). Psychopathology-associated mortality was higher in both groups but unintentional injuries-associated mortality only in the stable-high group.

Conclusions and Relevance

Experiencing affective symptoms and conduct problems in childhood and adolescence is associated with less favorable levels of biomarkers 28 years later and elevated risk of premature mortality. These findings, if causal and generalizable to younger cohorts, may imply that effective interventions on early-life mental health have the potential to shift the distribution of risk and improve population health.

Relationship between low skeletal muscle mass, sarcopenic obesity and left ventricular diastolic dysfunction in Korean adults

BACKGROUND

Heart failure with preserved ejection fraction is an emerging global health issue attributed to an ageing population. However, the association between low skeletal muscle mass, sarcopenic obesity, and left ventricular diastolic dysfunction remains unclear. In the current study, we aimed to investigate the relationship between low skeletal muscle mass, sarcopenic obesity, and diastolic dysfunction in a large cohort of Korean adults.

METHODS

We conducted a cross-sectional study of 31 258 subjects who underwent health examinations at Samsung Medical Centre's Health Promotion Centre in Seoul, Republic of Korea. Relative skeletal muscle mass was calculated using the skeletal muscle mass index [SMI (%) = appendicular skeletal muscle mass (kg)/body weight (kg) × 100], which was estimated by bioelectrical impedance analysis. Cardiac structure and function were evaluated by echocardiography.

RESULTS

Amongst the 31 258 subjects, 3058 (9.78%) were determined to have diastolic dysfunction. The odds ratio (OR) of diastolic dysfunction was 1.56 [95% confidence interval (CI): 1.31-1.85; p for trend <0.001] for the lowest SMI tertile relative to the highest SMI tertile following multivariable adjustment. Furthermore, the risk of diastolic dysfunction was much higher in the sarcopenic obesity (OR: 1.70, 95% CI: 1.44-1.99), followed by in the obesity-only (OR: 1.40, 95% CI: 1.21-1.62), and sarcopenia-only (OR: 1.32, 95% CI: 1.08-1.61) when compared with the nonobese, nonsarcopenic group. These results remained consistent amongst the elderly (age ≥ 65 years).

CONCLUSIONS

Our findings demonstrate that lower skeletal muscle mass and sarcopenic obesity are strongly associated with diastolic dysfunction in middle-aged and older adults.

A clinical evaluation of noninvasive and contactless radiofrequency technique in the treatment of abdominal fat

BACKGROUND

There is an increasing demand for fat reduction and body contouring procedures. Noninvasive radiofrequency devices have been used to tighten skin and treat cellulite, but there are few studies confirming their efficacy for abdominal fat reduction.

OBJECTIVE

This study explored the effects of four noninvasive radiofrequency (RF) treatments on abdominal fat in Asian subjects, evaluating body weight, body mass index (BMI), and waist circumference.

METHODS

In this study, 16 patients with abdominal obesity were treated four times with a noninvasive and contactless selective RF device (VANQUISH ME™, BTL Aesthetics). Treatments were 7 days apart and lasted 45 min each. The BMI and circumference of the upper, middle, and lower abdomen were measured at baseline and after each treatment.

RESULTS

There were statistically significant reductions in BMI and abdominal circumference in all 16 patients (P < .05). Most patients only experienced a slight abdominal heat sensation and minimal body sweating during the treatment, and no adverse reactions were observed after the treatment.

CONCLUSION

The noninvasive and contactless selective RF technique was effective and safe in reducing fat, BMI, and abdominal circumference.

Predictive Performance of Glycated Hemoglobin for Incident Diabetes Compared with Glucose Tolerance Test According to Central Obesity

BACKGROUND

To examine whether glycated hemoglobin (HbA1c) test would be a suitable screening tool for detecting high-risk subjects for diabetes compared to oral glucose tolerance test (OGTT) according to accompanied central obesity.

METHODS

In this prospective population-based cohort study, both OGTT and HbA1c tests were performed and continued every 2 years up to 12 years among individuals with non-diabetic state at baseline (aged 40 to 69 years, n=7,512). Incident diabetes was established by a doctor, HbA1c ≥6.5%, and/or fasting plasma glucose (FPG) ≥126 mg/dL, and/or 2-hour postprandial glucose (2hPG) level based on OGTT ≥200 mg/dL. Discriminative capacities of high HbA1c (≥5.7%) versus high 2hPG (≥140 mg/dL) for predicting incident diabetes were compared using Cox-proportional hazard regression and C-index.

RESULTS

During the median 11.5 years of follow-up period, 1,341 (17.6%) developed diabetes corresponding to an incidence of 22.1 per 1,000 person-years. Isolated high 2hPG was associated with higher risk for incident diabetes (hazard ratio [HR], 4.29; 95% confidence interval [CI], 3.56 to 5.17) than isolated high HbA1c (HR, 2.79; 95% CI, 2.40 to 3.26; P<0.05). In addition, high 2hPG provided better discriminatory capacity than high HbA1c (C-index 0.79 vs. 0.75, P<0.05). Meanwhile, in subjects with central obesity, the HR (3.95 [95% CI, 3.01 to 5.18] vs. 2.82 [95% CI, 2.30 to 3.46]) and discriminatory capacity of incident diabetes (C-index 0.75 vs. 0.75) between two subgroups became comparable.

CONCLUSION

Even though the overall inferior predictive capacity of HbA1c test than OGTT, HbA1c test might plays a complementary role in identifying high risk for diabetes especially in subjects with central obesity with increased sensitivity.

Patterns of change in cardiovascular risks of Korean male workers: a 10-year cohort analysis using the National Health Insurance Service-National Sample Cohort (NHIS-NSC) 2.0 database

OBJECTIVE

Health behaviour is one of the major determinants of cardiovascular diseases in working population. This study was tried to investigate the trend of cardiovascular health level, the relationship between continuous health behaviours, and changes in the risk of cardiovascular diseases of male workers by using a nationwide database.

DESIGN

This study is a retrospective cohort study.

SETTING AND PARTICIPANTS

The study analysed data of 57 837 male workers whose personal health examination data were continuously traced using Korea's National Health Insurance Service-National Sample Cohort 2.0 database.

PRIMARY OUTCOME MEASURES

A 10-year trend for all cardiovascular risks and change for the risks according to the consistent performance of healthy behaviours.

RESULTS

The results showed that the risk of being overweight (adjusted OR (aOR) 1.63, 95% CI 1.59 to 1.68) and obese (aOR 1.51, 95% CI 1.47 to 1.56) increased. The index of cardiovascular risk also increased for high fasting glucose (aOR 1.77, 95% CI 1.62 to 1.95) and high total cholesterol (aOR 1.68, 95% CI 1.60 to 1.76), respectively. The risks of high fasting glucose (aOR 2.09, 95% CI 1.40 to 3.13), high triglycerides (aOR 1.27, 95% CI 1.14 to 1.42) and high low-density lipoprotein cholesterol (aOR 1.38, 95% CI 1.14 to 1.66) were increased among high-risk smokers. Similarly, the risk of high total cholesterol (aOR 2.20, 95% CI 1.35 to 3.58) and high triglycerides (aOR 1.42, 95% CI 1.09 to 1.85) were increased among high-risk drinkers. In addition, the increase in the risk of being overweight (aOR 2.20, 95% CI 1.83 to 2.65) and obese (aOR 1.90, 95% CI 1.59 to 2.27) were analysed among who had not consistently exercised.

CONCLUSIONS

Since the pattern of change in the level of cardiovascular risk related to the continuous health behaviours of male workers was identified, the findings of the present study can be used as basic data to develop health promotion policies for the population.

Metabolic Syndrome and Risk of Lung Cancer: An Analysis of Korean National Health Insurance Corporation Database

INTRODUCTION

Metabolic syndrome is known to increase the risk of several cancers. However, the association between lung cancer and metabolic syndrome remains unclear. Thus, we investigated the impact of metabolic syndrome on the incidence of lung cancer.

METHODS

This study enrolled participants in a health screening program provided by the Korean National Health Insurance Service between January 2009 and December 2012. The incidence of lung cancer was observed until December 2016. We analyzed the risk of lung cancer according to the presence of metabolic syndrome, metabolic syndrome components, and number of metabolic syndrome components.

RESULTS

During the study, 45 635 new cases of lung cancer were recorded among 9 586 753 participants. The presence of metabolic syndrome and all its components was positively associated with the risk of lung cancer in men after multivariate adjustment (hazard ratio [HR] of metabolic syndrome 1.15; 95% confidence interval [CI], 1.12-1.18). The risk of lung cancer increased with the number of components present. The effect of metabolic syndrome on the increasing risk of lung cancer is may be higher in underweight male ever-smokers than in other participants.

CONCLUSION

Metabolic syndrome was associated with an increased risk of lung cancer in men. Moreover, the higher the number of metabolic syndrome components, the higher the risk of lung cancer.

Protective effect of smoking cessation on subsequent myocardial infarction and ischemic stroke independent of weight gain: A nationwide cohort study

Smoking cessation reduces the cardiovascular risk but increases body weight. We investigated the risk of subsequent myocardial infarction and ischemic stroke according to weight gain after smoking cessation, using a nationwide population based cohort. We enrolled 3,797,572 Korean adults aged over 40 years who participated in national health screenings between 2009 and 2010. Subjects who quit smoking were classified into three subgroups according to the weight change between baseline and 4 years prior. Myocardial infarctions and ischemic strokes were followed until the end of 2015. We compared the hazard ratios among smoking cessation subgroups, non-smokers, and current smokers. The mean changes in weight (1.5 ± 3.9 kg) of the smoking cessation group were higher than those of the other groups (p < 0.0001). A total of 31,277 and 46,811 subjects were newly diagnosed with myocardial infarction and ischemic stroke, respectively. Regardless of weight change, all subgroups of smoking cessation had significantly less risk than current smokers. The subgroup of smoking cessation with weight gain over 4kg showed the lowest risk for myocardial infarctions (hazard ratio 0.646, 95% confidence interval 0.583-0.714, p < 0.0001) and ischemic strokes (hazard ratio 0.648, 95% confidence interval 0.591-0.71, p < 0.0001) after multivariable adjustment. In conclusion, weight gain after smoking cessation did not adversely affect the cardiovascular protective effect.

SVM-based waist circumference estimation using Kinect

BACKGROUND AND OBJECTIVE

Conventional anthropometric studies using Kinect depth sensors have concentrated on estimating the distances between two points such as height. This paper deals with a novel waist measurement method using SVM regression, further widening spectrum of Kinect's potential applications. Waist circumference is a key index for the diagnosis of abdominal obesity, which has been linked to metabolic syndromes and other related diseases. Yet, the existing measuring method, tape measure, requires a trained personnel and is therefore costly and time-consuming.

METHODS

A dataset was constructed by recording both 30 frames of Kinect depth image and careful tape measurement of 19 volunteers by a clinical investigator. This paper proposes a new SVM regressor-based approach for estimating waist circumference. A waist curve vector is extracted from a raw depth image using joint information provided by Kinect SDK. To avoid overfitting, a data augmentation technique is devised. The 30 frontal vectors and 30 backside vectors, each sampled for 1 s per person, are combined to form 900 waist curve vectors and a total of 17,100 samples were collected from 19 individuals. On an individual basis, we performed leave-one-out validation using the SVM regressor with the tape measurement-gold standard of waist circumference measurement-values labeled as ground-truth. On an individual basis, we performed leave-one-out validation using the SVM regressor with the tape measurement-gold standard of waist circumference measurement-values labeled as ground-truth.

RESULTS

The mean error of the SVM regressor was 4.62 cm, which was smaller than that of the geometric estimation method. Potential uses are discussed.

CONCLUSIONS

A possible method for measuring waist circumference using a depth sensor is demonstrated through experimentation. Methods for improving accuracy in the future are presented. Combined with other potential applications of Kinect in healthcare setting, the proposed method will pave the way for patient-centric approach of delivering care without laying burdens on patients.

Sex- and age-specific effects of energy intake and physical activity on sarcopenia

Sarcopenia is a common health issue that is not limited to only elderly patients. However, many studies have reported factors to prevent sarcopenia only in susceptible groups. This study evaluates the relationship of the total energy intake to basal metabolic rate ratio (EI/BMR) and physical activity (PA) with sarcopenia. A second aim was to analyze the interaction between EI/BMR and PA by sex and age. We analyzed 16,313 subjects aged ≥ 19 years who had dual‒energy X-ray absorptiometry data. Sarcopenia was defined as appendicular lean mass/weight (%) that was 1 standard deviation below the sex-specific mean value for a young reference group. Multivariate logistic regression analysis was used to examine the interaction between EI/BMR and PA. In this study, as EI/BMR increased, the risk of sarcopenia decreased, particularly in the older groups. Both high PA and high EI/BMR were independently related to the reduced risk of sarcopenia and showed additive effects on reducing the risk in young male and older groups. However, high PA was associated with an increased risk of sarcopenia in the young female group with low energy intake. Our findings suggest that an adequate balance between energy intake and PA is related to a low risk of sarcopenia, especially in young females.

The Association between the Ratio of Energy Intake to Basal Metabolic Rate and Physical Activity to Sarcopenia: Using the Korea National Health and Nutrition Examination Surveys (2008-2011)

Background

Sarcopenia is an important health problem, the risk factors of which a few studies have reported on. The purpose of this study was to evaluate the correlation between sarcopenia and the ratio of total energy intake to basal metabolic rate (BMR) as well as physical activity, and determine whether the relationship was different between younger and older age groups using data from the 2008–2011 Korea National Health and Nutrition Examination Survey.

Methods

We analyzed 16,313 subjects older than 19 years who had dual energy X-ray absorptiometry data. Sarcopenia was defined as an appendicular lean mass/weight (%) ratio of 1 standard deviation below the sex-specific mean value for a younger reference group, and BMR was calculated using the Harris–Benedict equation. A chi-squared test and logistic regression analyses were performed to evaluate the factors associated with sarcopenia.

Results

In this study, 15.2% of males and 15.4% of females had sarcopenia. Energy intake/BMR as well as physical activity was negatively related to sarcopenia risk. In stratified analysis by age and sex, strength exercises showed an inverse association with sarcopenia only in males under the age of 50 years (odds ratio, 0.577; P<0.0001), whereas higher energy intake/BMR was negatively associated with sarcopenia in each age and sex group.

Conclusion

Our findings suggest that adequate energy intake is important to prevent sarcopenia regardless of whether one exercises.

Effect of sarcopenic obesity on deterioration of physical function in the elderly

BACKGROUND

Both sarcopenia and obesity are associated with decreased physical function of the elderly. Sarcopenic obesity (SO), which is the coexistence of sarcopenia and obesity, is expected to have a synergistic effect on physical function deterioration, but previous studies have shown varied results. This study aimed to investigate the impact of SO on the physical function of the elderly.

METHODS

Community-dwelling elderly subjects (1091 males; 1212 females; 70-84 years) were recruited in South Korea (eight cities). Body composition was measured via dual-energy X-ray absorptiometry and physical function was measured by grip strength, timed up and go test, and short physical performance battery (SPPB).

RESULTS

In males, grip strength and the total SPPB score in the SO group were significantly lower than those in the normal or pure obesity groups (p < 0.05). However, physical functions were not significantly different between the SO and the pure sarcopenia groups (p > 0.05). The trend for grip strength in females was similar to that in males, but the total SPPB score of the SO group was significantly lower than that of the other three groups (p < 0.05). Logistic regression analysis after covariate adjustment revealed that SO group males exhibited the highest risk of being in the lower SBBP score category (OR, 2.12; 95 % CI = 1.04-4.31); this trend was more prominent in females (OR, 3.75; 95 % CI = 2.01-7.00).

CONCLUSION

SO has a synergistic effect on physical function deterioration in the elderly compared with sarcopenia or obesity alone. Additionally, such an effect is more remarkable in females.

Effects of low skeletal muscle mass and sarcopenic obesity on albuminuria: a 7-year longitudinal study

We aimed to identify the association between low skeletal muscle, sarcopenic obesity, and the incidence of albuminuria in the general population using a longitudinal study. Data from 29,942 subjects who underwent two or more routine health examinations from 2006 to 2013 were retrospectively reviewed. Relative skeletal muscle mass was presented using the skeletal muscle mass index (SMI), a measure of body weight-adjusted appendicular skeletal muscle mass estimated by bioelectrical impedance analysis. The cumulative incidence of albuminuria was 981 (3.3%) during the 7-year follow-up period. The hazard ratio of incident albuminuria was 1.44 (95% CI: 1.22–1.71, p for trend <0.001) in the lowest SMI tertile relative to the highest SMI tertile after multivariable adjustment. After additionally adjusting for general and central obesity, the hazard ratio was 1.35 (95% CI: 1.13–1.61, p for trend = 0.001) and 1.30 (95% CI: 1.08–1.56, p for trend = 0.003), respectively. Furthermore, the risk of developing albuminuria was much higher in the sarcopenic obesity group (HR: 1.49, 95% CI: 1.21–1.81, p for trend <0.001) compared to the other groups. Sarcopenic obesity, as well as low skeletal muscle, may lead to albuminuria in general populations.

Waist circumference as a vital sign in clinical practice: a Consensus Statement from the IAS and ICCR Working Group on Visceral Obesity

Despite decades of unequivocal evidence that waist circumference provides both independent and additive information to BMI for predicting morbidity and risk of death, this measurement is not routinely obtained in clinical practice. This Consensus Statement proposes that measurements of waist circumference afford practitioners with an important opportunity to improve the management and health of patients. We argue that BMI alone is not sufficient to properly assess or manage the cardiometabolic risk associated with increased adiposity in adults and provide a thorough review of the evidence that will empower health practitioners and professional societies to routinely include waist circumference in the evaluation and management of patients with overweight or obesity. We recommend that decreases in waist circumference are a critically important treatment target for reducing adverse health risks for both men and women. Moreover, we describe evidence that clinically relevant reductions in waist circumference can be achieved by routine, moderate-intensity exercise and/or dietary interventions. We identify gaps in the knowledge, including the refinement of waist circumference threshold values for a given BMI category, to optimize obesity risk stratification across age, sex and ethnicity. We recommend that health professionals are trained to properly perform this simple measurement and consider it as an important 'vital sign' in clinical practice.

Effects of abdominal obesity on the association between air pollution and kidney function

OBJECTIVES

This study aimed to evaluate the associations between ambient air pollutants, obesity, and kidney function.

SUBJECTS/METHODS

We enrolled 3345 people who had undergone health checkups at Seoul National University Hospital. We recorded the annual average concentrations of ambient air pollutants, including particulate matter with an aerodynamic diameter of ≤10 μm (PM₁₀), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and carbon monoxide (CO), in each subject's residential area. Various obesity traits, such as body mass index, waist circumference, and visceral and subcutaneous adipose tissue areas, were measured by quantified computerized tomography (CT), and kidney function was assessed in relation to estimated glomerular filtration rate as an indicator of kidney function.

RESULTS

High PM₁₀, NO₂, SO₂, and CO concentrations were significantly associated with decreased kidney function (β = -2.39 and standard error = 0.32, -1.00 and 0.31, -1.23 and 0.28, and -1.32 and 0.29, respectively), and with the prevalence of chronic kidney disease (CKD). The association between air pollutant concentrations and decreased kidney function, including CKD, was stronger among those with high abdominal adiposity, as defined by CT measurement. For example, the association between increased concentrations of air pollutants and the prevalence of CKD was stronger in the group with greater visceral adiposity than in the group with less visceral adiposity (aORs = 1.29 vs 1.16 for PM₁₀, 1.42 vs 1.21 for SO₂, and 1.27 vs 1.11 for CO).

CONCLUSIONS

Long-term exposure to higher concentrations of air pollutants was unfavorably associated with kidney function and CKD prevalence, especially in people with abdominal obesity. This may indicate a high susceptibility to air pollutants in obese people.

A Novel Indicator of Children's Lipid Accumulation Product Associated with Impaired Fasting Glucose in Chinese Children and Adolescents

BACKGROUND

Diabetes is one of the most prevalent noncommunicable diseases worldwide. Children's lipid accumulation product (CLAP) is a novel indicator to show children's lipid accumulation and is effectively associated with metabolic syndrome among children and adolescents. The aim of the present study was to explore an association between CLAP and impaired fasting glucose (IFG) in Chinese children and adolescents.

METHODS

A total of 683 children and adolescents aged 8-15 years were recruited using the stratified cluster sampling method in this cross-sectional study and were measured for body height, weight, waist circumference (WC), abdominal skinfold thickness (AST), triglycerides (TG), fasting plasma glucose, dietary behaviors and physical activities. A logistic regression model and receiver operating characteristic (ROC) curve were used to compare the effects of CLAP for predicting IFG.

RESULTS

The prevalence of IFG in children and adolescents was 13.8%: 16.9% in boys and 10.1% in girls (P<0.05). The CLAP, height, weight, WC, AST, waist-to-height ratio (WHtR), and TG among boys with IFG were significantly higher than those among boys without IFG (P<0.05). The area under the ROC curve of CLAP for predicting IFG (0.637 (0.562-0.712)) was higher than those of WC, WHtR, AST, and TG. The cutoff point of P ₇₅ CLAP was the optimal value to predict IFG among boys, and the OR (95% CI) was 2.48 (1.40-4.42) and area under the ROC curve was 0.595 (0.513-0.676).

CONCLUSION

The CLAP was a novel indicator associated with IFG in Chinese boys, and it performed better than WC, WHtR, AST and TG.

Differences in the Association Among the Vitamin D Concentration, Dietary Macronutrient Consumption, and Metabolic Syndrome Depending on Pre- and Postmenopausal Status in Korean Women: A Cross-Sectional Study

BACKGROUND AND OBJECTIVES

To assess whether the consumption of dietary macronutrient could change metabolic syndrome (MetS) related to vitamin D deficiency according to menopausal status.

METHODS AND STUDY DESIGN

In a cross-sectional study of 8326 Korean women from the Korean National Health and Nutrition Examination Survey V (2010-2012), we investigated the combined interaction effect of serum 25-hydroxyvitamin D [25(OH)D] concentration and menopausal status on MetS-related variables.

RESULTS

The prevalence rates of 25(OH)D deficiency (vitamin D <50 nmol/L) among premenopausal and postmenopausal women were 84.5% and 67.9%, respectively. Significant differences in MetS-related variables such as body mass index (P<0.001), waist circumference (P=0.005), fast glucose (P=0.048), triglycerides (P=0.001), and high-density lipoprotein cholesterol (P=0.027) based on 25(OH)D concentration were observed among postmenopausal women but not among premenopausal women. Among the postmenopausal women with high consumption of dietary carbohydrate, the adjusted odds ratios (ORs) [95% confidence intervals (95% CIs)] of MetS among participants with 25(OH)D deficiency increased 1.380-fold (95% CI = 1.086-1.753) using the 25(OH)D-sufficient group as a reference. In contrast, the participants with 25(OH)D deficiency showed an increased risk of MetS [OR (95% CI) = 1.313 (1.041-1.655)] with low-fat consumption. However, the aforementioned findings did not differ among premenopausal women.

CONCLUSION

Thus, MetS due to 25(OH)D deficiency among postmenopausal women may be modified by the consumption of dietary macronutrient.

Lung function as a predictor of incident type 2 diabetes in community-dwelling adults: A longitudinal finding over 12 years from the Korean Genome and Epidemiology Study

AIM

Reduced lung function is associated with type 2 diabetes (T2D), but there are limited data in East Asian populations on the relationship between them. For this reason, this study investigated the longitudinal relationship of lung function with incident T2D in Korean adults.

METHODS

The study included 7583 non-diabetic adults aged 40-69 years from the Korean Genome and Epidemiology Study. Participants were divided into four groups according to gender-specific quartiles (Q1-Q4) of %PFVC and %PFEV₁. Also, HRs with 95% CIs for incident T2D were prospectively analyzed as per American Diabetes Association criteria using multivariate Cox proportional-hazards regression models.

RESULTS

During a 12-year follow-up, 1403 (18.5%) participants presented with newly developed T2D. HRs (95% CIs) of incident T2D in Q1 vs. Q4 (reference) of %PFVC were 1.67 (1.35-2.07) for men and 1.77 (1.39-2.24) for women and, of %PFEV₁, 1.58 (1.28-1.95) for men and 1.61 (1.27-2.03) for women, after adjusting for age, waist circumference, smoking status, alcohol intake, regular exercise, education levels, monthly household income, family history of diabetes, HOMA-IR, triglycerides, HDL cholesterol and high-sensitivity C-reactive protein levels.

CONCLUSION

Reduced lung function precedes and significantly predicts the future development of T2D independently of obesity, smoking and inflammation in community-dwelling middle-aged and elderly people.

Estimating the Cutoff Points of Time-Dependent Risk Factors by Using Joint Modeling of Longitudinal and Time-to-Event Data: A 14-Year Follow-up Study-Tehran Lipid and Glucose Study

Diagnostic accuracy and optimal cutoff points of risk factors is one of the important issues in medical decisions. In order to reassess the cutoff points of markers, longitudinal and time-to-event data of elderly individuals were collected repeatedly through 3 follow-up stages in the Tehran Lipid and Glucose Study. Time-dependent area under the ROC (receiver operating characteristic) curves (AUCs) based on the joint modeling of longitudinal and time-to-event data technique were measured. AUCs were considered to evaluate the discriminative potential of the models. The joint model produced higher AUC values than the Cox model; therefore, accuracy was improved although it is computationally complicated. The results had some differences with the thresholds reported in guidelines due to specificity to the population and/or the means of estimation methods. The estimated cutoff points with regard to sex can be used as a guideline for the Iranian elderly population.

Sex differences in the association between asthma incidence and modifiable risk factors in Korean middle-aged and older adults: NHIS-HEALS 10-year cohort

Background

This study investigated the sex-specific incidence of asthma and the effects of modifiable risk factors, particularly obesity, on asthma incidence among middle-aged and older individuals in Korea.

Methods

We used data from the National Health Insurance Service-Health Screening Cohort (NHIS-HEALS), which includes health examinees aged 40–79 years in 2002–2003. In total, 459,529 participants with baseline anthropometric measurements were followed-up for 10 years and the development of asthma was evaluated (2004–2013). For subgroup analysis, 246,019 participants who had body mass index (BMI) and waist circumference (WC) measurements taken in 2008–2009 were included in the analysis of the asthma incidence for 2010–2013. Factors associated with asthma were analysed using Cox proportional hazard models.

Results

The cohort comprised 4,248,813 (men, 2,358,541; women, 1,890,272) person-years of follow-up for 2004–2013. The asthma incidence was 10.58 and 15.03 per 1000 person-years for men and women, respectively. Asthma incidence increased with age, notably so in men. Obesity based on the baseline BMI was significantly associated with asthma development in both sexes (men, HR = 1.23, 95% confidence interval (CI) = 1.13–1.34; women, HR = 1.40 95% CI = 1.32–1.48). High WC was also related to asthma incidence in both sexes with statistical significance (men, HR = 1.34, 95% CI = 1.16–1.57; women, HR = 1.19 95% CI = 1.03–1.37). Analysis of the combined effects of BMI and WC showed that men had a higher asthma risk in the group with both general obesity and abdominal obesity than in the group with non-abdominal obesity and normal BMI. However, obese women had a higher risk of asthma regardless of abdominal obesity. Similarly, smoking was associated with asthma in both sexes but drinking and physical activity showed different associations between the sexes.

Conclusions

Our results revealed that asthma incidence was substantially high at old age and lifestyle factors were associated with asthma development. Practical strategies including weight control and healthy lifestyle modification are required to prevent asthma in older people.

Association between Serum Gamma-Glutamyltransferase and Prevalence of Metabolic Syndrome Using Data from the Korean Genome and Epidemiology Study

BACKGROUND

The aim of this study was to determine whether there is a positive correlation between gamma-glutamyltransferase (GGT) levels and the prevalence of metabolic syndrome and whether GGT can be used as an easily checkable metabolic index using data from the large-scale Korean Genome and Epidemiology Study (KoGES).

METHODS

We obtained data of 211,725 participants of the KoGES. The collected data included age, sex, height, weight, waist circumference, and various biochemical characteristics, including serum GGT levels. The data of study participants who ingested more than 40 g/day of alcohol and who were diagnosed with metabolic syndrome at baseline was excluded. We analyzed the prevalence of metabolic syndrome according to GGT quartiles in both genders.

RESULTS

The GGT level was significantly higher in subjects with metabolic syndrome compared to normal subjects (37.92±48.20 mg/dL vs. 25.62±33.56 mg/dL). The prevalence of metabolic syndrome showed a stepwise increase with GGT quartiles in both male and female subjects. Compared to the lowest GGT quartile, the odds ratio was 1.534 (95% confidence interval [CI], 1.432 to 1.643), 1.939 (95% CI, 1.811 to 2.076), and 2.754 (95% CI, 2.572 to 2.948) in men and 1.155 (95% CI, 1.094 to 1.218), 1.528 (95% CI, 1.451 to 1.609), and 2.022 (95% CI, 1.921 to 2.218) in women with increasing GGT quartile. The cutoff value of GGT predicting risk of metabolic syndrome was 27 IU/L in men and 17 IU/L in women.

CONCLUSION

We suggested that GGT could be an easily checkable marker for the prediction of metabolic syndrome.

Lower Leg Fat Depots Are Associated with Albuminuria Independently of Obesity, Insulin Resistance, and Metabolic Syndrome (Korea National Health and Nutrition Examination Surveys 2008 to 2011)

BACKGROUND

Although the involvement of obesity in metabolic disorders is well known, leg fat depot influences on albuminuria have not been determined.

METHODS

This population-based, cross-sectional study used a nationally representative sample of 2,076 subjects aged ≥20 years from the Korea National Health and Nutrition Examination Surveys of 2008 to 2011. The ratio of leg fat to total fat (LF/TF ratio) was assessed by dual X-ray absorptiometry, and albuminuria was defined as more than one positive dipstick test or an albumin-to-creatinine ratio of ≥30 mg/g.

RESULTS

Individuals whose LF/TF ratio was in the lowest tertile showed a higher proportion of albuminuria than those in the highest tertile (odds ratio [OR], 2.82; 95% confidence interval [CI], 2.01 to 3.96; P<0.001). This association was observed in both sexes, all age groups, and all subgroups stratified by body mass index, waist circumference, homeostasis model assessments of insulin resistance, and the presence of metabolic syndrome (all, P<0.05). Multiple logistic regression analyses also demonstrated that the lowest LF/TF ratio was independently associated with albuminuria risk (OR, 1.55 to 2.16; all, P<0.05). In addition, the risk of albuminuria was higher in sarcopenic individuals with lower LF/TF ratios than in the highest LF/TF ratio subjects without sarcopenia (OR, 3.73; 95% CI, 2.26 to 6.13).

CONCLUSION

A lower LF/TF ratio was associated with an increased risk of albuminuria independent of obesity, insulin resistance, and metabolic syndrome, and when combined with sarcopenia, the albuminuria risk synergistically increased. Hence, our findings may have implications to improve risk stratification and recommendations on body fat distribution in the general population.

The Association between Obesity Phenotypes and Early Renal Function Decline in Adults without Hypertension, Dyslipidemia, and Diabetes

Background

The prevalence of chronic kidney disease is increasing worldwide. Several studies have suggested that obesity is associated with early renal dysfunction. However, little is known about the relationship between obesity phenotypes and early renal function decline. Therefore, this study aimed to identify the relationship between obesity phenotypes and early renal function decline in adults without hypertension, dyslipidemia, and diabetes.

Methods

We conducted a cross-sectional analysis of clinical and anthropometric data from 1,219 patients who underwent a routine health checkup in 2014. We excluded adults with cardiovascular disease, renal disease, diabetes, hypertension, dyslipidemia, or low glomerular filtration rate (<60 mL/min/1.73 m²). Renal function was determined according to the estimated glomerular filtration rate calculated using the Chronic Kidney Disease Epidemiology Collaboration creatinine-cystatin C equation.

Results

Age, sex, body mass index, waist circumference, triglyceride, low-density lipoprotein, and fasting glucose had an association with the estimated glomerular filtration rate. After adjusting for age, sex, smoking status, and alcohol intake, the odds ratios of the metabolically abnormal normal weight and metabolically abnormal obese phenotypes for the presence of low estimated glomerular filtration rates were 1.807 (95% confidence interval, 1.009– 3.236) and 1.834 (95% confidence interval, 1.162–2.895), compared with the metabolically healthy normal weight phenotype. However, the metabolically healthy obese phenotype did not show a significant association with early renal function decline.

Conclusion

In this cross-sectional study, we confirmed the association between the metabolically abnormal normal weight and metabolically abnormal obese phenotypes and early kidney function decline in adults without hypertension, dyslipidemia, and diabetes.

The Risk of Myocardial Infarction and Ischemic Stroke According to Waist Circumference in 21,749,261 Korean Adults: A Nationwide Population-Based Study

BACKGROUND

Waist circumference (WC) is a well-known obesity index that predicts cardiovascular disease (CVD). We studied the relationship between baseline WC and development of incident myocardial infarction (MI) and ischemic stroke (IS) using a nationwide population-based cohort, and evaluated if its predictability is better than body mass index (BMI).

METHODS

Our study included 21,749,261 Koreans over 20 years of age who underwent the Korean National Health Screening between 2009 and 2012. The occurrence of MI or IS was investigated until the end of 2015 using National Health Insurance Service data.

RESULTS

A total of 127,289 and 181,637 subjects were newly diagnosed with MI and IS. The incidence rate and hazard ratio of MI and IS increased linearly as the WC level increased, regardless of adjustment for BMI. When the analyses were performed according to 11 groups of WC, the lowest risk of MI was found in subjects with WC of 70 to 74.9 and 65 to 69.9 cm in male and female, and the lowest risk of IS in subjects with WC of 65 to 69.9 and 60 to 64.9 cm in male and female, respectively. WC showed a better ability to predict CVD than BMI with smaller Akaike information criterion. The optimal WC cutoffs were 84/78 cm for male/female for predicting MI, and 85/78 cm for male/female for predicting IS.

CONCLUSION

WC had a significant linear relationship with the risk of MI and IS and the risk began to increase from a WC that was lower than expected.

Plasma sphingomyelins increase in pre-diabetic Korean men with abdominal obesity

Abdominal or visceral obesity is a well-known risk factor for metabolic diseases. However, whether abdominal obesity significantly affects plasma lipid profile during the development of type 2 diabetes has not been fully elucidated. We investigated the differences in plasma lipid concentrations in 63 participants categorized into six groups (middle-aged Korean men); Normal, Pre-diabetes (pre-DM), and Diabetes mellitus (DM) with or without abdominal obesity (AO or lean). The lipidomic profiles were determined by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Sphingomyelin (SM) levels in plasma were significantly higher in the pre-DM with AO than in pre-DM with lean (p = 0.021). SM concentrations correlated positively with waist-to-hip ratio (WHR) (r = 0.256, p = 0.044), cholesteryl ester (CE) (r = 0.483, p < 0.0001), ceramide (r = 0.489, p < 0.0001) and plasmanyl phosphatidylcholine (PC) (r = 0.446, p < 0.0001). The present study found that pre-diabetic patients with AO were characterized by increased plasma concentrations of SM. Plasma SM levels in individuals with AO may be an early prognostic biomarker to better predict the progression toward type 2 diabetes and metabolic syndrome.