Yoonsuk Jekal

Improved Insulin Sensitivity and Adiponectin Level after Exercise Training in Obese Korean Youth

Objective: The objective of this study was to investigate the association among adiposity, insulin resistance, and inflammatory markers [high‐sensitivity C‐reactive protein (hs‐CRP), interleukin (IL)‐6, and tumor necrosis factor (TNF)‐α] and adiponectin and to study the effects of exercise training on adiposity, insulin resistance, and inflammatory markers among obese male Korean adolescents.

Reduced serum vaspin concentrations in obese children following short-term intensive lifestyle modification

BACKGROUNDnRecently, visceral adipose tissue-derived serpin (vaspin) was identified as a potential insulin sensitizing adipokine, however, the factors determining the levels of circulating vaspin levels have not been fully understood. We investigated the association between adiposity, insulin resistance, lipid profiles and inflammatory markers including vaspin levels, and the effects of short-term intensive lifestyle modification on circulating vaspin levels in overweight or obese children.nnnMETHODSnA total of 50 (25 boys, 25 girls) overweight or obese children aged 11 to 13 years (average age: 12.0+/-0.9 y, BMI: 25.35+/-86 kg/m(2)) who complied with inclusion criteria participated in our study. To determine the association between adiposity, insulin resistance, lipid profiles and inflammatory markers including vaspin levels, cross-sectional analyses were performed. Thereafter, subjects underwent a tightly controlled seven-day intensive lifestyle modification including physical activity, dietary modification, and behavioral modification education in residence of a local university dormitory.nnnRESULTSnThere was a negative correlation between vaspin concentration and fasting insulin (r=-.325, p<0.05) and homeostasis model assessment of insulin resistance (HOMA-IR) (r=-.331, p<0.05) when percent body fat was controlled. Multivariate linear regression analysis found serum vaspin level to be an independent predictor of insulin and HOMA-IR. Short-term intensive lifestyle modification significantly decreased vaspin levels by 39.28% (pre: .84+/-1.0, post: .51+/-1.0 ng/ml, p<0.001) while adiponectin levels increased by 11.2% (pre: 6.50+/-2.89, post: 7.28+/-2.98 ng/ml, p<0.01). In addition, short-term lifestyle modification significantly improved HOMA-IR (pre: 3.58+/-1.93, post 1.30+/-1.9, p<0.001) and lipid profiles.nnnCONCLUSIONSnSerum vaspin level is one of the predictors for insulin resistance and was significantly reduced following short-term lifestyle modification.

Interaction between fatness and fitness on CVD risk factors in Asian youth.

The purpose of this study was to investigate the effects of fatness and fitness on insulin resistance (IR) and cardiovascular disease (CVD) risk factors among Korean adolescents. A total of 322 male high school students participated Departme nt of Sport and Leisure Studies, Yonsei University, Seoup, Republic of Korea Department of Sport and Leisure Studies, Yonsei University, Seoup, Republic of Korea in the cross-sectional part of the study. To determine the interaction of fatness and fitness levels on IR and CVD risk factors, subjects were stratified into four groups based on their body mass index (BMI) and cardio-respiratory fitness. Subjects who were in the high-fat category had significantly higher IR and CVD risk score than subjects in the low-fat category regardless of their fitness level. Subjects who were in high-fat-high-fit group showed significantly lower IR and CVD risk score than high-fat-low-fit group. Twenty-nine obese and unfit subjects participated in the intervention study. Twelve weeks of exercise training significantly reduced body weight (4.11+/-0.75 kg) and improved VO(2max) which resulted in a significant improvement in IR and CVD risk score (2.16+/-0.62 vs. 0.20+/-0.75). Interestingly, improvement in cardio-respiratory fitness and small reduction in body weight in relatively short-term significantly reduced the CVD risk score to the level of low-fat-low-fit subjects. Our results show the importance of fitness in determining IR and CVD risk factors among obese adolescents.

The association between pentraxin 3 and insulin resistance in obese children at baseline and after physical activity intervention.

BACKGROUNDnThe role of pentraxin-3 (PTX3) in the development of insulin resistance is still not clear. We aimed to test 1) whether circulating PTX3 levels are associated with insulin resistance and 2) whether changes in PTX3 levels after the physical activity are associated with changes in insulin resistance.nnnMETHODSnFifty-seven overweight or obese children (39 boys, 18 girls; age: 12.04±0.82y, BMI: 26.5±1.2 kg/m²) participated in the study. All participants were housed together and their amount of physical activity (1823.5±1.34 kcal/day) and food intake (1882±68.8 kcal/day) were tightly controlled.nnnRESULTSnCirculating PTX3 levels at baseline were negatively associated with fasting insulin (r=-.336, p=0.012) and homeostasis model assessment of insulin resistance (HOMA-IR) (r=-.334, p=0.014) even after adjustment for BMI and Tanner stage. The degree of change in PTX3 levels notably associated with changes in fasting insulin (r=-.280, p=0.035) and HOMA-IR (r=-.281, p=.034) in response to the physical activity intervention. Subgroup analysis further indicates that HOMA-IR was improved more in subjects whose PTX3 levels were increased compared with subjects who PTX3 levels were decreased (HOMA-IR delta: -2.33±1.3 vs -1.46±0.70, p=0.004).nnnCONCLUSIONnPTX3 is negatively associated with insulin resistance and associated with changes in insulin resistance induced by physical activity in overweight and obese children.

Low Levels of Physical Activity Are Associated with Increased Metabolic Syndrome Risk Factors in Korean Adults

Background Low levels of physical activity (PA) are strongly associated with the development of metabolic syndrome (MetS) and chronic diseases. However, few studies have examined this association in Koreans. The primary purpose of this study was to examine the associations between PA and MetS risks in Korean adults. Methods A total of 1,016 Korean adults (494 males and 522 females) participated in this study. PA levels were assessed using the International PA Questionnaire. MetS risk factors were determined using clinically established diagnostic criteria. Results Compared with the highest PA group, the group with the lowest level of PA was at greater risk of high triglyceride (TG) in males (odds ratio [OR], 1.87; 95% confidence interval [CI], 1.07 to 3.24) and of hemoglobin A1c ≥5.5% in females (OR, 1.75; 95% CI, 1.00 to 3.04) after adjusting for age and body mass index. Compared with subjects who met the PA guidelines, those who did not meet the guidelines were more likely to have low high density lipoprotein cholesterol in both males (OR, 1.69; 95% CI, 1.11 to 2.58), and females (OR, 1.82; 95% CI, 1.20 to 2.77). Furthermore, those who did not meet the PA guidelines were at increased risk of high TG levels in males (OR, 1.69; 95% CI, 1.23 to 2.86) and abnormal fasting glucose (OR, 1.93; 95% CI, 1.17 to 3.20) and MetS (OR, 2.10; 95% CI, 1.15 to 3.84) in females. Conclusion Increased levels of PA are significantly associated with a decreased risk of abnormal MetS components.

Association between Obesity and Physical Fitness, and Hemoglobin A1c Level and Metabolic Syndrome in Korean Adults

Background The purpose of the current study was to investigate the association of obesity level, physical fitness level, hemoglobin A1c (HbA1c) level and metabolic syndrome (MetS) risk factors among Korean adults. Methods A total of 557 adults (272 males and 285 females) who underwent medical check-up at local hospital were recruited. In addition to regular health check-up, cardiopulmonary fitness, muscular endurance were measured and their association were analyzed. Results The prevalence of MetS was 31.7% for males and 23.7% for females. Females with the higher muscular endurance had lower waist circumference, triglyceride level, and HbA1c level than those with the lower muscular endurance. Males with the higher level of cardiopulmonary fitness had lower diastolic blood pressure, lower high-sensitivity C-reactive protein level and higher high density lipoprotein cholesterol level than males with the lower level of cardiopulmonary fitness. Females with the higher level of cardiopulmonary fitness had lower body weight, body mass index, systolic blood pressure, and fasting blood glucose level than females with the lower level of cardiopulmonary fitness. Participants with the higher level of adiposity and the lower level of physical fitness were 5.26 times (95% confidence interval [CI], 2.19 to 12.62), 5.71 times (95% CI, 2.23 to 14.60) more likely to have MetS, respectively, in male and female compared to participants who were neither obese nor have the lower level of fitness. Conclusion This study suggests that maintaining a healthy body weight as well as a certain level of fitness is important for the prevention of MetS.

Middle-aged women's awareness of cholesterol as a risk factor: Results from a national survey of Korean Middle-aged Women's Health Awareness (KomWHA) study

BACKGROUNDnDyslipidemia, a risk factor for cardiovascular disease (CVD), is more prevalent in middle-aged women than in men of the same age in Korea. This study, the first national survey that focused on cholesterol in Korean women, aimed to: (1) assess their awareness and knowledge of cholesterol, (2) evaluate their risk reduction behavior, and (3) examine differences in these variables among geographical regions in Korea.nnnMETHODSnA questionnaire survey study was conducted in a randomly selected national sample of 1304 Korean women, aged 40-64 years in 3 geographic regions.nnnRESULTSnHigh cholesterol was identified as a cause of CVD by 54.4% of respondents, however, 95.4% did not know their own values. Only 4.1% of respondents were aware of desirable level of total cholesterol. Eight percent of respondents perceived correctly the meaning of high-density lipoprotein cholesterol (HDL-C) as good cholesterol. And 32.9% had cholesterol check at least once a year. No significant regional differences were found in womens awareness and knowledge on cholesterol. No smoking (93.6%), low salt diet (52.5%) and weight management (50.6%) were the most prevalent risk reduction behaviors. Women in the rural area performed less risk reduction behaviors than those in urban area.nnnCONCLUSIONSnGiven the low level of awareness and knowledge about cholesterol in these women, nurses need to increase their education about cholesterol and risk reduction behaviors of CVD for middle-aged Korean women, particularly those in rural area. To resolve identified disparities in womens risk reduction behaviors between the rural and urban area, a national-level health policy can result in a successful effort to promote womens awareness of cholesterol and risk reduction behaviors for the cardiovascular health of the public.

Reduced serum total osteocalcin is associated with central obesity in Korean children.

BACKGROUNDnRecently, osteocalcin (OC), an osteoblast-derived hormone, has been suggested as a new link between obesity and insulin resistance in humans. However, few studies regarding the relationship between OC and obesity in Asian children have been published. We investigated the association of OC with adiposity, insulin resistance and metabolic syndrome (MetS) in Korean children.nnnMETHODSnTwo hundred and nine (100 boys, 109 girls) children (age: 9.78 ± 1.05 years, body mass index (BMI): 22.27 ± 5.34 kg/m(2)) participated in this cross-sectional study. Anthropometric parameters, insulin resistance, lipid profiles, total OC, and an inflammatory marker, C-reactive protein (CRP), were measured. MetS phenotype was also determined.nnnRESULTSnSerum total OC levels were significantly lower in overweight or obese children (76.96 ± 27.08 ng/ml vs. 66.91 ± 21.39 ng/ml, p = 0.020) and it was negatively associated with body fat after controlling for age, gender and BMI. Serum total OC concentrations were significantly lower in participants with central obesity or at least two components of MetS driven by waist circumference than they were in those with none. Stepwise linear regression results also showed that serum total OC was partially explained by age, gender, waist-to-hip ratio, and fasting glucose.nnnCONCLUSIONSnThis study supported a negative association between serum total OC and adiposity in children. OC may be associated with childhood central obesity; however, further research using more accurate measurements is needed to identify the association between these variables.

The Relationship between the Level of Fatness and Fitness during Adolescence and the Risk Factors of Metabolic Disorders in Adulthood

Background The purpose of the current study was to investigate the association between the level of obesity and physical fitness (PF) during adolescence and the risk factors of metabolic disorders during adulthood. Methods In the current analysis, 3,993 Korean adults (mean age, 38.70 ± 1.69 years) were recruited. The level of body index (BI) and PF were examined during adolescence through high school record, and their health examination data, including systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting glucose (FG), total cholesterol (TC), and current body mass index (BMI) were obtained from National Health Insurance Corporation Data. Gender-specific analyses were administered to compare health exam data across the level of BI, the level of PF, and a mixed level of BI and PF. Results Most obese males during high school had statistically higher SBP, DBP, FG, and BMI in adulthood, and most obese females had higher BMI, as compared to most lean males or females. Least fit males during high school had statistically higher BMI in adulthood, and least fit females had statistically higher SBP, DBP, FG, TC, and BMI, as compared to most fit males or females. There was a significant relationship between the mixed level of BI and PF and SBP, DBP, TC and current BMI in both genders. Conclusion Maintaining a healthy level of body weight and PF during adolescence is recommended to prevent the development of metabolic diseases in adulthood.

The effect of predominant breast-feeding on the risk of obesity in Korean preschool children

The purpose of this study was to investigate the prevalence of predominant breast-feeding practices based on the criteria given by the World Health Organization and to identify the association between predominant breast-feeding during infancy and the development of obesity during preschool in South Korean children. This study employed a nonexperimental, retrospective study design. Five hundred and twenty-eight preschool children aged three to six years and their mothers were recruited. Twenty-seven percent of the participants engaged in predominant breast-feeding; on average they fed predominantly breast milk for the first 6.7 months. After adjusting for child and maternal characteristics, children who had mixed feeding were 1.68 times more likely to become obese than those who were predominantly breast-fed. In this study, it was identified that predominant breast-feeding has a positive effect on maintaining healthy body weight in Korean preschoolers. While encouraging predominant breast-feeding is only a part of the solution, it is an effective and important first step toward preventing preschool obesity.