Kyoungwoo Kim

Distribution of Abdominal Visceral and Subcutaneous Adipose Tissue and Metabolic Syndrome in a Korean Population

OBJECTIVE This study aimed to assess the correlation between abdominal subcutaneous adipose tissue (SAT) and metabolic syndrome (MetS) in Korean adults after adjusting for the effects of visceral adipose tissue (VAT). RESEARCH DESIGN AND METHODS The SAT/VAT ratio (SVR) was calculated using abdominal computed tomography in 2,655 subjects. We used regression analyses to assess whether the SVR predicted MetS. RESULTS For both sexes, the prevalence of elevated triglycerides, reduced HDL, and elevated fasting glucose significantly decreased with increasing quintiles of SVR (P for trend < 0.05). The prevalence and odds ratios of MetS significantly decreased as the SVR increased (men: odds ratio 0.5 [95% CI 0.3–0.7]; women: 0.2 [0.1–0.5] for comparisons of lowest vs. highest quintile; P for trend < 0.05). CONCLUSIONS After adjustment for VAT, abdominal SAT was inversely correlated with the occurrence of MetS.

Alcohol consumption and higher incidence of impaired fasting glucose or type 2 diabetes in obese Korean men

It is inconclusive whether moderate alcohol consumption reduces the diabetes risk. We observed the development of impaired fasting glucose or type 2 diabetes according to the amount of alcohol intake and body mass index. The annual health evaluation data of 2,500 male workers from 2002 to 2006 were reviewed retrospectively deleting personal identification code. The information contained sex, age, medical history, smoking status, alcohol consumption, participating regular exercise, anthropometric, and biochemistry measurement. Impaired fasting glucose or diabetes was determined when fasting plasma glucose was > or =100mg/dL. Thousand seven hundred seven subjects were eligible after excluding medical history of diabetes or fasting glucose > or =100mg/dL at baseline. The relative risks of its development in group of taking 1-14, 15-29, and > or =30.0g ethanol were 0.842 (95% confidence interval [CI], 0.603-1.176), 1.068 (95% CI, 0.736-1.551), and 1.019 (95% CI, 0.662-1.568) within normal weight group, 1.164 (95% CI, 0.795-1.705), 1.421 (95% CI, 0.947-2.133), and 1.604 (95% CI, 1.031-2.495) within overweight group, and 1.498 (95% CI, 1.042-2.153), 1.634 (95% CI, 1.091-2.447), and 1.563 (95% CI, 1.019-2.396) within obese group each after adjusting age, family history of diabetes, smoking, exercise, serum fasting glucose, aspartate aminotransferase, and gamma-glutamyltransferase with nondrinkers as a reference group. Not only high alcohol consumption but also moderate drinking was related with higher incidence of impaired fasting glucose or diabetes in obese Korean men.

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.

Higher quality primary care is associated with good self-rated health status

OBJECTIVE To ascertain the association between primary care quality and self-rated health status. METHODS A cross-sectional study using the Korean primary care assessment tool (K-PCAT). The K-PCAT is a validated tool based on the definition of primary care in Korea, consisting of 5 domains and 21 items providing a total primary care quality score. Data were collected from patients of family physicians working at nine private clinics as their usual source of care. The main outcome measure was self-rated health status. RESULTS Data were analyzed for 531 study participants. Bivariate analysis of socio-demographic variables of patients, who participated in this study as primary care quality assessors, revealed that those with high self-ratings of health tended to have higher household incomes and more frequent exercise. Those with high self-ratings of health had higher total primary care scores than those with low self-ratings of health, as determined through bivariate analysis (P < 0.01). After being adjusted for age, sex, the number of diseases being treated, education years, household income, smoking status, alcohol intake and the frequency of regular exercise, the total primary care score was found to be positively associated with good health. CONCLUSIONS Primary care quality, as assessed by the K-PCAT, was positively associated with good self-rated health status.

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.

Association between cigarette smoking history and mortality in 36,446 health examinees in Korea.

BACKGROUND It is well known that smoking is a preventable factor for all-cause mortality; however, it is still questionable how many years after smoking cessation that people will have reduced risk for mortality, in particular in those with a high interest in their own health. We aimed to examine the association between time since quitting smoking and total mortality among past-smokers relative to current smokers. MATERIALS AND METHODS We enrolled 36,446 health examinees that voluntarily taken with diverse health check-up packages of high cost burden in 1995-2003 and followed them till death by 2004. The history of cigarette smoking consumption was collected using a self-administrative questionnaire at the first visit time. Mortality risk by smoking cessation years was analyzed using Coxs proportional hazard model. RESULTS Compared to non-smokers, male smokers over 15 pack-years had higher risk for total mortality (HR=1.49, 95%CI 1.02-2.18). The mortality risk in female smokers with same pack-years was more pronounced than that in male smokers (HR=2.83, 95%CI 1.17-7.04) despite a small number of cases. Compared to current smokers, a decrease of total mortality was observed among those who ceased smoking, and inverse dose-response was found with years after cessation: RR 0.98 (95%CI, 0.64-1.41) (<2 yrs), 0.60 (95%CI, 0.43-0.83) (3-9 yrs), and 0.58 (95%CI, 0.43-0.79) (≥10 yrs). CONCLUSIONS A reduced risk of total mortality was observed after 3 years of smoking cessation. Our findings suggest that at least 3 years of smoking cessation may contribute to reduce premature mortality among Asian men.

Animal and Plant Protein Intake and Body Mass Index and Waist Circumference in a Korean Elderly Population

Controversy exists on whether animal and plant proteins influence obesity differently. The purpose of this study was to evaluate the association between total, animal, and plant protein intake with the body mass index (BMI), waist circumference (WC), and renal function in the Korean elderly. Study participants included Korean adults aged 60 years or older from the Korean National Health and Nutrition Examination Survey in 2013–2014. Height, weight, and waist circumference were measured and the body mass index was calculated. One-day 24-hour recall data were used to estimate daily total, animal, and plant protein intake. Glomerular filtration rate (GFR) was calculated by using the Modification of Diet in Renal Disease (MDRD) equation. General linear modellings were used to assess the relationships between protein intake, BMI and WC. The mean age was 69.2 ± 0.2 years and 44.2% were male. The total daily protein intake was 1.1 ± 0.02 g/kg/day and 0.9 ± 0.02 g/kg/day for males and females, respectively. Only one third of protein intake was from animal sources. In males, BMI (regression coefficient (95% CI); −1.30 (−1.55, −1.06), p < 0.001; −0.29 (−0.52, −0.05), p = 0.016; −1.30 (−1.8, −1.02), p < 0.001, respectively) and WC (−3.87 (−4.58, −3.16), p < 0.001; −0.90 (−1.58, −0.22), p = 0.010; −3.88 (−4.68, −3.08), p < 0.001, respectively) decreased as daily intake of plant protein (g/kg/day), animal protein (g/kg/day) and total protein (g/kg/day) increased. Similar associations were shown in Korean females. GFR was not associated with protein intake regardless of protein source in both sexes. In Korean adults aged 60 years or older, the protein intake was associated with a favorable obesity index without decrease in renal function. The effect was similar in both males and females, with both animal and plant proteins.

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.