Yang-Im Hur

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 (β = −0.10, p = 0.02 and β = −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 (β = −0.08, p < 0.05). There was a significant positive relationship between consumption of sugar from SSBs and cMetS at baseline (β = 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.

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 womens 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 womens smoking status.

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.

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 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/m2 vs. 23.9 kg/m2, 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.

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.

Related Factors of Insulin Resistance in Korean Children: Adiposity and Maternal Insulin Resistance

Increased adiposity and unhealthy lifestyle augment the risk for type 2 diabetes in children with familial predisposition. Insulin resistance (IR) is an excellent clinical marker for identifying children at high risk for type 2 diabetes. This study was conducted to investigate parental, physiological, behavioral and socio-economic factors related to IR in Korean children. This study is a cross-sectional study using data from 111 children aged 7 years and their parents. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated using fasting glucose and insulin level as a marker of IR. All children’s adiposity indices (r = 0.309–0.318, all P-value = 0.001) and maternal levels of fasting insulin (r = 0.285, P-value = 0.003) and HOMA-IR (r = 0.290, P-value = 0.002) were positively correlated with children’s HOMA-IR level. There was no statistical difference of children’s HOMA-IR level according to children’s lifestyle habits and socioeconomic status of families. An increase of 1 percentage point in body fat was related to 2.7% increase in children’s HOMA-IR (P-value < 0.001) and an increase of 1% of maternal level of HOMA-IR was related to 0.2% increase in children’s HOMA-IR (P-value = 0.002). This study shows that children’s adiposity and maternal IR are positively associated with children’s IR.

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

Abstract 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.

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.