Application of Machine Learning Algorithms to Predict Osteoporotic Fractures in Women.

BACKGROUND: Predicting the risk of osteoporotic fractures is vital for prevention. Traditional methods such as the Fracture Risk Assessment Tool (FRAX) model use clinical factors. This study examined the predictive power of the FRAX score and machine-learning algorithms trained on FRAX parameters. METHODS: We analyzed the data of 2,147 female participants from the Ansan cohort study. The FRAX parameters employed in this study included age, sex (female), height and weight, current smoking status, excessive alcohol consumption (>3 units/d of alcohol), and diagnosis of rheumatoid arthritis. Osteoporotic fracture was defined as one or more fractures of the hip, spine, or wrist during a 10-year observation period. Machine-learning algorithms, such as gradient boosting, random forest, decision tree, and logistic regression, were employed to predict osteoporotic fractures with a 70:30 training-to-test set ratio. We evaluated the area under the receiver operating characteristic curve (AUROC) scores to assess and compare the performance of these algorithms with the FRAX score. RESULTS: Of the 2,147 participants, 3.5% experienced osteoporotic fractures. Those with fractures were older, shorter in height, and had a higher prevalence of rheumatoid arthritis, as well as higher FRAX scores. The AUROC for the FRAX was 0.617. The machine-learning algorithms showed AUROC values of 0.662, 0.652, 0.648, and 0.637 for gradient boosting, logistic regression, decision tree, and random forest, respectively. CONCLUSION: This study highlighted the immense potential of machine-learning algorithms to improve osteoporotic fracture risk prediction in women when complete FRAX parameter information is unavailable.

Body mass index, waist circumference and cardiovascular diseases in transitional ages (40 and 66 years).

BACKGROUND: There is lack of data on effect modification by age on the association between body mass index (BMI) or waist circumference (WC) and cardiovascular diseases (CVDs). We aimed to investigate the impact of BMI and WC on incident CVDs in individuals aged 40 and 66 years. METHODS: Overall, 2 430 510 participants who underwent a national health screening for transitional ages provided by the Korean National Health Insurance Service between 2009 and 2012 were included. The adjusted hazard ratios and 95% confidence intervals for myocardial infarction (MI), ischaemic stroke and CVDs as a composite outcome of MI and ischaemic stroke were calculated using multivariable Cox proportional hazard regression analysis. RESULTS: During a mean follow-up of 7.7 years, 24 884 MI and 29 415 ischaemic stroke events occurred. Among participants aged 40 years, there was a J-shaped association of BMI with incident CVDs, MI and ischaemic stroke with nadir at BMI 18.5-22.9 kg/m2 (P for trend < 0.001 for all). Among those aged 66 years, there were significant U-shaped associations of BMI with CVDs and MI with nadir at a BMI of 23.0-24.9 kg/m2 (P for trend 0.013 and 0.017, respectively). WC was linearly associated with all study outcomes in both age groups (P for trend < 0.001). The impact of general and abdominal obesity on both study outcomes was more prominent in those aged 40 years than in those aged 66 years (P for interaction < 0.001). CONCLUSIONS: To prevent cardiovascular risk, weight loss intervention should be cautiously implemented and individualized according to age. The maintenance of muscle mass may be essential in managing weight loss particularly in older population.

COVID-19 and related social distancing measures induce significant metabolic complications without prominent weight gain in Korean adults.

Background: This study using multi-center health examination data from Korean adults was conducted to confirm changes in weight, and their related cardiometabolic parameters, before and after strengthening of social distancing regulations. Methods: A retrospective cohort study was conducted using health check-up data from 13 university hospitals. The study period was from January 2018 to July 2020. To examine the effect of systematic social distancing measures, participants who underwent a health check-up (Visit 3) between July 2020 and July 2021 (during full scale social distancing), and had undergone two previous health check-ups (Visits 1 and 2) between January 2018 and June 2020 (before social distancing), were selected. In total, data from 7,875 participants were analyzed. Linear mixed-effect models were used to calculate estimates of anthropometric indices and metabolic markers measured on Visits 2 and 3, compared with measurements from Visit 1. Results: There were no significant differences in body weight, body mass index, waist circumference, and body composition on Visit 3 than on Visits 1 and 2. However, the odds of metabolic syndrome and its components, including hypertension, high glucose, diabetes, hypercholesterolemia, hypertriglyceridemia, hyper-non-high-density lipoprotein cholesterolemia, and dyslipidemia were significantly higher on Visit 3 than on Visits 1 and 2. The increase in metabolic complications was marked, particularly in relatively young adults who visited health check-up centers located in the capital area. Conclusion: Metabolic syndrome and its components were significantly worse after high level social distancing, although there were no significant increases in anthropometric indices and body fat levels. Healthcare providers need to prevent and manage worsening of metabolic parameters in subpopulations prone to be more sedentary and eat unhealthy food during the COVID-19 pandemic and associated social distancing measures.

Fatty Liver Change in Korean Adults in a Systematic Social Distancing System Amid the COVID-19 Pandemic: A Multicenter Analysis.

In response to the COVID-19 pandemic, the Korean government implemented policies including the systematic social distancing (SSD) system which started on 28 June 2020. The present study investigated the development and aggravation of fatty liver measured using ultrasonography during the transition period (from pre-SSD to SSD) compared to the fatty liver changes during the pre-SSD period. Changes in fatty liver and liver enzymes were assessed in different groups stratified by alcohol consumption. Our retrospective cohort analysis included 5668 participants who underwent health checkups at 13 university hospitals during the SSD period and two or more checkups before the SSD period. Fatty liver developed and aggravated more in the transition period (13.6% development and 12.0% aggravation) than in the pre-SSD period (10.8% development and 10.1% aggravation) in the alcohol consumption group. This finding was more prominent in women than in men. Abnormal alanine transaminase levels were more often developed in the transition period than in the pre-SSD period, especially in men (11.1% vs. 8.6% in each period). In conclusion, the SSD system may contribute to fatty liver changes in individuals who regularly consume alcohol. Further research of the post-pandemic period is needed to assess long-term changes in fatty liver disease.

Factors Associated with Body Weight Gain among Korean Adults during the COVID-19 Pandemic.

Background: Obesity is of grave concern as a comorbidity of coronavirus disease 2019 (COVID-19). We examined the factors associated with weight gain among Korean adults during the COVID-19 pandemic. Methods: We conducted an online survey of 1,000 adults (515 men and 485 women aged 20-59 years) in March 2021. Multivariable logistic regression analysis was performed to evaluate the factors associated with weight gain. The analysis was adjusted for sex, age, region, depressive mood, anxiety, eating out, late-night meals, alcohol consumption, exercise, sleep disturbance, meal pattern, subjective body image, comorbidities, marital status, living alone, and income. Results: After adjusting for confounding variables, the odds for weight gain increased in the group aged 20-34 years compared with the group aged 50-59 years (1.82; 95% confidence interval [CI], 1.01-3.32). Women were more associated with the risk of weight gain compared with men. The odds for weight gain increased in the lack of exercise group compared with the exercise group (4.89; 95% CI, 3.09-7.88). The odds for weight gain increased in the eating-out and late-night meal groups compared with that in the groups not eating out and not having late-night meals. Individuals watching a screen for 3-6 hr/day were more associated with the risk of weight gain compared with those who rarely watched a screen. The odds for weight gain increased in participants who considered themselves obese compared with those who did not consider themselves obese. Conclusion: A healthy diet and regular physical activity tend to be the best approach to reduce obesity, a risk factor for COVID-19.

Effects of a mobile healthcare service provided by public health centers on practicing of health behaviors and health risk factors.

BACKGROUND/OBJECTIVES: This study evaluated whether a mobile health (mHealth) application can instigate healthy behavioral changes and improvements in metabolic disorders in individuals with metabolic abnormalities. SUBJECTS/METHODS: Participants were divided into an mHealth intervention group (IG), which used a mobile app for 24 weeks, and a conventional IG. All mobile apps featured activity monitors, with blood pressure and glucose monitors, and body-composition measuring devices. The two groups were compared after 24 weeks in terms of health-behavior practice rate and changes in the proportion of people with health risks, and health behaviors performed by the IG that contributed to reductions in more than one health risk factor were analyzed using multiple logistic regression. RESULTS: Preference for low-sodium diet, reading nutritional facts, having breakfast, and performing moderate physical activity significantly increased in the mHealth IG. Furthermore, the mHealth IG showed a significant increase of eight items in the mini-dietary assessment; particularly, the items "I eat at least two types of vegetables of various colors at every meal" and "I consume dairies, such as milk, yogurt, and cheese, every day." The proportion of people with health risks, with the exception of fasting glucose, significantly decreased in the mHealth IG, while only the proportion of people with at-risk triglycerides and waist circumference of females significantly decreased in the control group. Finally, compared to those who did not show improvements of health risks, those who showed improvements of health risks in the mHealth IG had an odds ratio of 1.61 for moderate to vigorous physical activity, 1.65 for "I do not add more salt or soy sauce in my food," and 1.77 for "I remove fat in my meat before eating." CONCLUSIONS: The findings suggest that the additional use of a community-based mHealth service through a mobile application is effective for improving health behaviors and lowering metabolic risks in Koreans.

The Mediating Role of Parental Support in the Relationship between Life Stress and Suicidal Ideation among Middle School Students.

BACKGROUND: Youth suicide is increasingly being recognized as a major social problem in South Korea. In this study, we aimed to explore the effects of parental support on the relationship between life stress and suicidal ideation among middle-school students. METHODS: This study analyzed data from a cross-sectional study on mental health conducted by the South Korea National Youth Policy Institute between May and July of 2013. Questionnaire responses from 3,007 middle-school students regarding stress factors, thoughts of suicide during the past year, and parental support were analyzed in terms of 3 subscale elements: emotional, academic, and financial support. RESULTS: Among the participants, 234 male students (7.8%) and 476 female students (15.8%) reported experiencing suicidal ideation in the past year. Life stress significantly influenced suicidal ideation (P<0.001), and parental support and all of the subscale elements had a significant influence on decreasing suicidal ideation. As shown in model 1, life stress increased suicidal ideation (adjusted odds ratio [aOR], 1.318; P<0.001), and, in model 2, the effect of life stress on suicidal ideation decreased with parental support (aOR, 1.238; P<0.001). CONCLUSION: Parental support was independently related to a decrease in suicidal ideation, and life stress was independently related to an increase in suicidal ideation. Parental support buffered the relationship between life stress and suicidal ideation.

Usefulness of the Waist Circumference-to-Height Ratio in Screening for Obesity and Metabolic Syndrome among Korean Children and Adolescents: Korea National Health and Nutrition Examination Survey, 2010-2014.

The aims of this study were to assess the diagnostic value of the weight-to-height ratio (WHtR) for the detection of obesity and metabolic syndrome (MS) in Korean children and adolescents, and to determine the advantages of WHtR as a population-based screening tool in comparison with other obesity indicators, such as body mass index (BMI) and waist circumference (WC). We performed a cross-sectional analysis of data from 3057 children and adolescents (1625 boys, 1332 girls) aged 10-19 years who were included in the fifth Korean National Health and Nutrition Examination Survey (KNHANES, 2010-2012) up to the second year of the sixth KNHANES (2013-2014). Receiver operation characteristic (ROC) curves were generated to determine the optimal cutoff value and accuracy of WHtR for predicting individual obesity indicators or more than two non-WC components of MS. The area under the ROC curve (AUC) is a measure of the diagnostic power of a test. A perfect test will have an AUC of 1.0, and an AUC equal to 0.5 means that the test performs no better than chance. The optimal WHtR cutoff for the evaluation of general obesity and central obesity was 0.50 in boys and 0.47-0.48 in girls, and the AUC was 0.9. Regarding the assessment of each MS risk factor, the optimal WHtR cutoff was 0.43-0.50 in boys and 0.43-0.49 in girls, and these cutoffs were statistically significant only for the detection of high triglyceride and low High-density lipoprotein (HDL) cholesterol levels. When a pairwise comparison of the AUCs was conducted between WHtR and BMI/WC percentiles to quantify the differences in power for MS screening, the WHtR AUC values (boys, 0.691; girls, 0.684) were higher than those of other indices; however, these differences were not statistically significant (boys, p = 0.467; girls, p = 0.51). The WHtR cutoff value was 0.44 (sensitivity, 67.7%; specificity, 64.6%) for boys and 0.43 (sensitivity, 66.4%; specificity, 66.9%) for girls. There was no significant difference between the diagnostic power of WHtR and that of BMI/WC when screening for MS. Although the use of WHtR was not superior, WHtR is still useful as a screening tool for metabolic problems related to obesity because of its convenience.

The Relationship between Smoking and Unhealthy Weight Control Behaviors among Korean Adolescents: The Tenth Korea Youth Risk Behavior Web-Based Survey, 2014.

BACKGROUND: Adolescent smoking is positively related to weight control attempts, especially by unhealthy methods. The co-occurrence of smoking and unhealthy weight control behaviors may cause serious health problems in adolescents. This study examined the relationship of smoking with unhealthy weight control behaviors among Korean adolescents. METHODS: This cross-sectional study involved 31,090 students of grades 7 to 12, who had tried to reduce or maintain their weight during the 30 days prior to The Tenth Korea Youth Risk Behavior Web-based Survey, 2014. Data on height, weight, weight control methods, smoking, alcohol intake, living with one's family, and perceived economic status were obtained through self-report questionnaires. 'Unhealthy weight control behaviors' were subcategorized into 'extreme weight control behaviors' and 'less extreme weight control behaviors.' RESULTS: The smoking rates were 13.3%±0.4% in boys and 3.8%±0.2% in girls. Current smokers were more likely to engage in extreme weight control behaviors (odds ratio [OR], 1.47; 95% confidence interval [CI], 1.09 to 2.00 in boys, and OR, 2.05; 95% CI, 1.59 to 2.65 in girls) and less extreme weight control behaviors (OR, 1.23; 95% CI, 1.07 to 1.40 in boys, and OR, 1.47; 95% CI, 1.22 to 1.76 in girls) compared to non-smokers among both boys and girls. CONCLUSION: Current smoking is independently related to a high likelihood of engaging in unhealthy weight control behaviors among Korean adolescents. This relationship is stronger for girls than for boys. Extreme weight control behaviors have a stronger relationship with current smoking than less extreme weight control behaviors.

Relationship between obesity and depression in Korean adults: Korea National Health and Nutrition Examination Survey 2014.

Previous studies on the relationship between obesity and depression have produced conflicting results. And only a limited number of studies have been conducted in Asians, and few large-scale nationwide studies have been conducted in Korean populations.We investigated the relationship between obesity and depression in Korean adults using data from a population-based sample from the 2014 Korea National Health and Nutritional Examination Survey (KNHANES) by cross-sectional study.In total, 4026 subjects (1692 men, 2334 women) aged 19 to 69 years participated in the 2014 KNHANES. Current depression was defined as a score ≥10 on the 9-item Patient Health Questionnaire. Height and weight were measured and the body mass index (BMI) was calculated. The participants were asked to complete questionnaires about socio-demographic factors and disease comorbidities, and health-related behaviors. The chi-squared test and multivariate logistic regression analyses were performed to examine the relationship between obesity and depression.Depression was diagnosed in 5.7% of the study participants (3.9% of men, 7.0% of women). According to body weight status, there was a significant difference in the prevalence of depression (underweight: 16.2%, normal weight: 5.5%, overweight: 4.3%, obese [BMI ≥30]: 6.9%). Compared with the normal weight group, the underweight group had a higher adjusted odds ratio (OR) for depression (OR = 3.27, 95% confidence interval [CI]: 1.22, 8.75 in men; OR = 2.00, 95% CI: 1.12, 3.57 in women). Overweight (OR = 0.60, 95% CI: 0.32, 1.13) and obese (OR = 0.62, 95% CI: 0.17, 2.27) men had lower ORs for depression, but this trend was not significant. Compared with normal weight women, obese women had higher adjusted ORs for depression (OR = 1.75, 95% CI: 0.79, 3.88), while overweight women had lower ORs for depression (OR = 0.90, 95% CI: 0.56, 1.45), but these trends were not significant.This study shows differences in the risk of depression depending upon body weight status. Being underweight was correlated with a high risk of developing depression in both men and women, but obesity cannot be ruled out as a risk factor for this condition.

Weight Control Methods Related to Cotinine-Verified Smoking among Korean Adult Women: Korea National Health and Nutrition Examination Survey, 2008-2011.

BACKGROUND: Korean women are known to have a very low smoking rate. However, the actual smoking rate among Korean women is higher than 10% and may continue to increase gradually. In addition, some Korean women use extreme weight control methods that have potentially harmful effects. This study was conducted to elucidate weight control methods related to cotinine-verified smoking among Korean adult women. METHODS: This cross-sectional study involved 4,189 women aged ≥19 years who had attempted weight control during the past 1 year from the Korea National Health and Nutrition Examination Survey, 2008-2011. Smoking status was assessed using both self-report questionnaires and assays of urinary cotinine, and weight control methods were investigated using self-report questionnaires. RESULTS: The smoking rate based on the measurement of urinary cotinine was 12.4% ± 0.8% among Korean women. Cotinine-verified smokers were more likely to attempt fasting (odds ratio, 2.19; 95% confidence intervals, 1.03 to 4.67), taking prescription diet-pills (odds ratio, 2.37; 95% confidence intervals, 1.47 to 3.82), and taking nonprescription diet-pills (odds ratio, 3.46; 95% confidence intervals, 1.71 to 6.98), and were less likely to attempt eating less food or modifying dietary patterns (odds ratio, 0.71; 95% confidence intervals, 0.51 to 0.99) compared to non-smokers. CONCLUSION: Korean adult women's smoking is independently related to a high likelihood of using weight control methods with potentially harmful effects, such as fasting and taking diet-pills, and a low likelihood of choosing weight control methods, including dietary modification, that require constant effort for a prolonged time.

Associations between Sugar Intake from Different Food Sources and Adiposity or Cardio-Metabolic Risk in Childhood and Adolescence: The Korean Child-Adolescent Cohort Study.

The increasing prevalence of childhood obesity is a serious public health problem associated with co-morbidities in adulthood, as well as childhood. This study was conducted to identify associations between total sugar intake and sugar intake from different foods (fruit, milk, and sugar-sweetened beverages (SSBs)), and adiposity and continuous metabolic syndrome scores (cMetS) among Korean children and adolescents using cohort data. The study subjects were children (n = 770) who participated in the 4th year (2008) of the Korean Child-Adolescent Cohort Study (KoCAS). Dietary intake data were collected via three-day 24-h food records, and sugar intake was calculated for the total sugar content of foods using our database compiled from various sources. Anthropometric measurements, assessments of body composition, and blood sample analysis were performed at baseline and at follow-up four years later. The cMetS was calculated based on waist circumference, triglycerides, high-density lipoprotein cholesterol, glucose, and mean arterial blood pressure. According to multiple linear regression analysis, there were no significant associations between total sugar intake and adiposity and cMetS. However, higher intake of fruit sugar at baseline was significantly associated with lower body mass index (BMI) z-scores and body fat percentages at baseline (ß = -0.10, p = 0.02 and ß = -0.78, p < 0.01, respectively). At follow-up, sugar intake from fruit at baseline was still negatively associated with the above outcomes, but only the relationship with BMI z-scores retained statistical significance (ß = -0.08, p < 0.05). There was a significant positive relationship between consumption of sugar from SSBs and cMetS at baseline (ß = 0.04, p = 0.02), but that relationship was not observed at follow-up (p = 0.83). Differences in consumption sugars from fruit and SSBs might play an important role in the risk of adiposity and metabolic disease in children and adolescents. Our results suggest that strategies for reducing sugar intake need to target particular food groups. Consequently, this information could be of value to obesity- and metabolic disease-prevention strategies.

Sociodemographic characteristics of underweight korean adults: Korea national health and nutrition examination survey, 2007-2010.

BACKGROUND: Underweight is associated with increased risk of mortality and morbidity. It is reported that the prevalence of underweight is increasing among Korean young women. However, there have been few studies on sociodemographic factors related to being underweight. This study was conducted to elucidate the sociodemographic characteristics of Korean underweight adults. METHODS: This study is a cross-sectional study of 7,776 adults aged 25 to 69 years using data from the Korea National Health and Nutrition Examination Survey, 2007-2010. Study subjects were composed of underweight and normal-weight adults excluding overweight adults. Body mass index was calculated from measured height and weight. Health behaviors such as smoking, drinking, and physical activity were surveyed through self-administered questionnaires, and socioeconomic status, marital status, and history of morbidity were surveyed through face-to-face interviews. RESULTS: Women had a higher frequency of underweight (10.4% vs. 7.0%, P < 0.001) than men. Among men, current smoking (odds ratio [OR], 1.62) and past history of cancer (OR, 2.55) were independently related to underweight. Among women, young age (OR, 2.06), former smoking (OR, 1.69), and being unmarried (OR, 1.56) were identified as independently related factors of underweight. In addition, among both men and women, alcohol drinking (men OR, 0.57; women OR, 0.77) and past history of chronic diseases (men OR, 0.55; women OR, 0.43) were independently related to a lower frequency of underweight. CONCLUSION: We showed that various sociodemographic factors were associated with underweight. It was ascertained that there were differences in the sociodemographic factors related to underweight between Korean men and women.

Weight control attempts in underweight korean adults: Korea national health and nutrition examination survey, 2007-2010.

BACKGROUND: Underweight refers to the weight range in which health risk can increase, since the weight is lower than a healthy weight. Negative attitudes towards obesity and socio-cultural preference for thinness could induce even underweight persons to attempt weight control. This study was conducted to investigate factors related to weight control attempts in underweight Korean adults. METHODS: This was a cross-sectional study on 690 underweight adults aged 25 to 69 years using data from the Korea National Health and Nutrition Examination Survey, 2007-2010. Body image perception, weight control attempts during the past one year, various health behaviors, history of chronic diseases, and socioeconomic status were surveyed. RESULTS: Underweight women had a higher rate of weight control attempts than underweight men (25.4% vs. 8.1%, P < 0.001). Among underweight men, subjects with the highest physical activity level (odds ratio [OR], 7.75), subjects with physician-diagnosed history of chronic diseases (OR, 7.70), and subjects with non-manual jobs or other jobs (OR, 6.22; 12.39 with reference to manual workers) had a higher likelihood of weight control attempts. Among underweight women, subjects who did not perceive themselves as thin (OR, 4.71), subjects with the highest household income level (OR, 2.61), and unmarried subjects (OR, 2.08) had a higher likelihood of weight control attempts. CONCLUSION: This study shows that numbers of underweight Korean adults have tried to control weight, especially women. Seeing that there are gender differences in factors related to weight control attempts in underweight adults, gender should be considered in helping underweight adults to maintain a healthy weight.

The cutoff value of waist circumference for predicting metabolic risks in pre- and post-menopausal korean women: analysis of 2010 korean national health and nutrition examination survey data.

BACKGROUND: With metabolic syndrome (MS) being a major risk factor for cardiovascular disease, and central obesity being a major predisposing factor for MS, intensive research is currently being performed on cutoff values according to race and sex. Menopause is an especially significant factor in designating cutoff values for female central obesity, as menopause brings sudden bodily changes that induce central obesity and increased prevalence of MS. Therefore this study aimed to investigate the cutoff values for the obesity index and its validity in predicting the criteria for MS in Korean women according to menstrual status. METHODS: The study focused on 3,103 women 20 years of age or older participating in the 2007 Korea National Health and Nutrition Examination Survey. Definitions of non-adipose components of MS were defined by the International Diabetes Federation, and menstrual status was judged on the basis of survey results. The sensitivity, specificity, and positive and negative predictive values of the central obesity index (body mass index [BMI], waist circumference [WC], waist-to-height ratio [WHtR]) according to menstrual status for two or more non-adipose components of MS were calculated based on the Youden index. RESULTS: Area under the curve (AUC) values predicting the presence of two or more metabolic risk factors were higher in pre-menopausal women, with AUC values for BMI, WC, and WHtR being, in pre- and post-menopausal women, 23.1 kg/m(2) vs. 23.9 kg/m(2), 76.1 cm vs. 82.5 cm, and 0.49 vs. 0.53, respectively. The WC cut off (76 cm) for pre-menopausal women was found to be more sensitive and more effective at screening for MS risks than the cutoff value given by the Korea Society for the Study of Obesity. CONCLUSION: The central obesity index showed better predictability for MS risk in pre-menopausal women. Because the central obesity index cutoff values are lower in pre-menopausal women, the possibility of metabolic risk can be considered for pre-menopausal women with WC lower than 85 cm. Assessment and control of other risks are needed accordingly for preventing the development of MS.

New diagnostic criteria for obesity and overweight in Korean children and adolescents using 2007 Korean National Growth Charts.

The diagnostic criteria (KCDC Criteria) to define obesity and overweight of Korean children and adolescents were newly presented in the 2007 Korean National Growth Charts. The KCDC Criteria were criticized for several problems caused by upward shift of body mass index (BMI) percentile curves of the growth charts. This study was conducted to establish new diagnostic criteria (New Criteria) for obesity and overweight in Korean children and adolescents that would be less affected by a change of BMI distribution in the reference population of the Growth Charts. The BMI values for ages 2-18 years corresponding to Asia-Pacific adult BMI cutoffs of obesity (25.0 kg/m(2)) and overweight (23.0 kg/m(2)) were calculated with L, M and S values presented in the 2007 Korean National Growth Charts. Additionally, we examined the frequencies of obesity and overweight among children and adolescents who participated in the 2005 National Growth Survey based on both New Criteria and KCDC Criteria. The Z-scores corresponding to BMIs of 25 and 23 kg/m(2) at 18-years-of-age were 0.99 and 0.41 in boys, and 1.34 and 0.71 in girls, respectively. The BMI values corresponding to these Z-scores from age 2 to 18 years were determined as new BMI cutoffs for obesity and overweight. The frequencies of obesity and overweight estimated by New Criteria were greater by 2 times in boys and 1.5 times in girls than those by KCDC Criteria. We suggest that New Criteria could be a good alternative that can resolve problems caused by upward shift of BMI percentile curves of the 2007 Korean National Growth Charts.

Marital Status and Health Behavior in Middle-aged Korean Adults.

BACKGROUND: Marital status is as an important sociodemographic variable for health studies. We assessed the association between marital status and health behavior in middle-aged Korean adults. METHODS: This is a cross-sectional study of 2,522 Korean middle-aged adults (1,049 men, 1,473 women) from the 2010 Korean National Health and Nutrition Examination Survey. The subjects were classified as living with a partner or living without a partner (never married, separated, widowed, and divorced). We assessed the relationship between marital status and five health behaviors (smoking, high-risk alcohol intake, regular exercise, regular breakfast consumption, and undergoing periodic health screening). RESULTS: Age, income level, educational level, and occupational classification were all significantly associated with marital status. The risk of undergoing health screening (odds ratio [OR], 0.53; 95% confidence interval [CI], 0.32 to 0.90) and having regular breakfast (OR, 0.50; 95% CI, 0.27 to 0.92) were significantly lower in men living without a partner than with a partner. Women living without a partner had a higher smoking risk (OR, 2.27; 95% CI, 1.09 to 4.73) and a higher risk of high-risk alcohol consumption (OR, 5.33; 95% CI, 1.65 to 17.24) than their counterparts. CONCLUSION: Korean middle-aged adults living with partners are more likely to have healthier behavior than living without a partner. The association between marital status and health behaviors differed by sex.

Socioeconomic Indicators Associated with Initiation and Cessation of Smoking among Women in Seoul.

BACKGROUND: While smoking prevalence in Korean men has been decreasing, it is increasing in Korean women. Little is known about women's smoking inequalities in Korea. This study was conducted to investigate the association of socioeconomic indicators with the initiation and cessation of smoking among Korean women. METHODS: This was a cross-sectional study on 9,089 women aged 25-64 years from the 2008 Seoul Community Health Survey. The data on smoking and socioeconomic status were obtained through face-to-face interviews. Smoking initiation rate was defined as the proportion of the individuals who had started smoking at least one cigarette among all subjects. Smoking cessation rate was calculated by dividing the number of individuals who had quit smoking by the number of ever smokers. Education level, total family income and occupation were investigated as socioeconomic indicators. RESULTS: Education level was significantly associated with both initiation and cessation of smoking. Lower educated women had a higher likelihood of smoking initiation (odds ratio [OR], 1.72; 95% confidence interval [CI], 1.17 to 2.51) but lower likelihood of smoking cessation (OR, 0.38; 95% CI, 0.22 to 0.66) than higher educated women. Smoking initiation rate was higher in manual workers (OR, 1.65; 95% CI, 1.20 to 2.27) than in non-manual workers. However, there were no significant differences of both initiation and cessation of smoking according to total household income. CONCLUSION: This study shows that there are smoking inequalities among Korean women. It is thought that education level and occupation are important determinants of women's smoking status.

Prevalence of dietary supplement use in Korean children and adolescents: insights from Korea National Health and Nutrition Examination Survey 2007-2009.

The purpose of this study was to estimate the prevalence of dietary supplement (DS) use in Korean children and adolescents and to examine the related factors associated with DS use from the 4th Korea National Health and Nutrition Examination Survey. Total 6,131 participants aged between 2 and 18 yr were included in the analysis. We estimated the prevalence of DS use mainly from the DS questionnaire data of the Nutrition Survey. Reported supplements were classified according to the Health Functional Food Code. We also assessed the relationship between DS use and anthropometry, socioeconomic factors, health behaviors, and chronic diseases. Approximately 34% of Korean children and adolescent was taking DS. Younger age (P = 0.003), higher household income (P < 0.001), presence of chronic diseases (P = 0.05), regular meal consumption (P = 0.002), frequent snack consumption (P = 0.001), and normal body mass index rather than overweight (P = 0.10) or obesity (P = 0.03) were associated with the DS use after adjustment for related factors. Vitamin/mineral supplements (343.5/10(3) persons) were the most commonly taken DS in Korean children and adolescents, followed by Omega-3 (28.8), ginseng (18.3), colostrums (14.1) and chlorella/spirulina (10.0). In conclusion, DS use is common as much as in 34% of Korean children and adolescents and is associated with age, household income level, chronic diseases, meal regularity, and obesity status.

The Relationship between Serum Gamma-glutamyltransferase Level and Overweight in Korean Urban Children.

BACKGROUND: Recently, it has been reported that gamma-glumyltransferase (GGT) is associated with various cardiovascular risk factors including overweight in adults. However, there are few studies on the relationship between GGT and cardiovascular risk factors in children. The aim of this study was to assess the relationship between serum GGT level and overweight in Korean urban children. METHODS: This study was a cross-sectional study using data on 390 4th grade students of elementary schools in Gunpo, Korea. Children were divided into 4 groups according to gender-specific quartiles of serum GGT level. Body mass index, waist circumference and body fat percentage were quantified as adiposity indices. RESULTS: All adiposity indices in children of the highest GGT level quartile were higher than those in children of the lowest quartile. Adjusted odd ratios on overweight of the highest quartile of GGT level compared to the lowest quartile were 14.40 (95% confidence interval [CI], 4.43 to 46.83) in boys and 2.94 (95% CI, 1.06 to 8.16) in girls. CONCLUSION: This study shows that high serum GGT level is related with overweight in Korean urban children and this relationship is stronger in boys compared to girls.