Byung Yeon Yu

Adiponectin Induces Growth Arrest and Apoptosis of MDA-MB- 231 Breast Cancer Cell

Recently, it was reported that reduction in serum adiponectin levels is correlated with the incidence of breast cancer. As an effort to explain this, we screened various human breast cancer cell lines to identify those in which proliferation is directly controlled by adiponectin. Among the five tested cell lines, proliferation of MDA-MB-231 cancer cell was significantly suppressed by adiponectin within the range of physiological concentration. Furthermore, prolonged adiponectin treatment caused cell growth arrest and even apoptosis of MDA-MB-231. This result is the first to show that adiponectin can directly control cancer cell growth and provides a rationale for the theory that reduction in plasma adiponectin levels could be a risk factor for breast cancer.

A coronary heart disease prediction model: the Korean Heart Study

Objective The objectives of this study were to develop a coronary heart disease (CHD) risk model among the Korean Heart Study (KHS) population and compare it with the Framingham CHD risk score. Design A prospective cohort study within a national insurance system. Setting 18 health promotion centres nationwide between 1996 and 2001 in Korea. Participants 268 315 Koreans between the ages of 30 and 74 years without CHD at baseline. Outcome measure Non-fatal or fatal CHD events between 1997 and 2011. During an 11.6-year median follow-up, 2596 CHD events (1903 non-fatal and 693 fatal) occurred in the cohort. The optimal CHD model was created by adding high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol and triglycerides to the basic CHD model, evaluating using the area under the receiver operating characteristic curve (ROC) and continuous net reclassification index (NRI). Results The optimal CHD models for men and women included HDL-cholesterol (NRI=0.284) and triglycerides (NRI=0.207) from the basic CHD model, respectively. The discrimination using the CHD model in the Korean cohort was high: the areas under ROC were 0.764 (95% CI 0.752 to 0.774) for men and 0.815 (95% CI 0.795 to 0.835) for women. The Framingham risk function predicted 3–6 times as many CHD events than observed. Recalibration of the Framingham function using the mean values of risk factors and mean CHD incidence rates of the KHS cohort substantially improved the performance of the Framingham functions in the KHS cohort. Conclusions The present study provides the first evidence that the Framingham risk function overestimates the risk of CHD in the Korean population where CHD incidence is low. The Korean CHD risk model is well-calculated alternations which can be used to predict an individuals risk of CHD and provides a useful guide to identify the groups at high risk for CHD among Koreans.

The Korean Heart Study: rationale, objectives, protocol, and preliminary results for a new prospective cohort study of 430,920 men and women.

Background To describe the rationale, objectives, protocol, and preliminary results for a new prospective cohort study of cardiovascular disease (CVD) risk factors in South Korea. Methods Study members were recruited from participants in routine health assessments at health promotion centres across South Korea. Established and emerging CVD risk factors were measured. Eighteen centres holding electronic health records agreed to linkage of participants’ records to future health insurance claims for monitoring of disease events. The recruitment of 430,920 participants (266,782 men, 164,138 women), aged 30–74 years, provides broad geographical reach across South Korea. Results Risk factor prevalence was more favourable in women than men, and, in general, in the younger rather than older study members. There was also close similarity between the characteristics of the present sample and the Korean National Health and Nutrition Examination Survey. The expected associations between risk factors and both CVD and death were also apparent. Conclusions Data from the present sample, based on data linkage, show close agreement with South Korea-wide surveys (for risk factor prevalence) and the extant literature (for risk factor associations). These findings gives confidence in future results anticipated from this cohort study of east Asians – a group that has been traditionally under-researched.

Comparison of Visceral Fat and Liver Fat as Risk Factors of Metabolic Syndrome

The principal objective of this study was to determine whether visceral fat or liver fat is a more relevant risk factor for metabolic syndrome. A total of 98 subjects aged 18-65 yr, who visited a health promotion center in a university hospital, were enrolled in this study. Metabolic syndrome was diagnosed based on the modified National Cholesterol Education Programs Adult Treatment Panel III report (NCEP-ATPIII) criteria. We defined the visceral obesity as a visceral fat area of ≥ 100 cm2 which was acquired by CT at the L4-5 level. To evaluate fatty liver, we applied a liver-to-spleen attenuation ratio ≤ 1.1 as measured by CT at the T12 level. We employed binary logistic regression models that used the presence or absence of metabolic syndrome as a dependent variable and age, sex, and the presence or absence of visceral obesity and fatty liver as independent variables. Visceral obesity was not found to be an independent variable as a risk factor of metabolic syndrome (odds ratio 2.7; 95% confidence interval 0.55-13.30), but fatty liver was found to be significant in this model (odds ratio 71.3; 95% CI 13.04-389.53). Our study suggests that liver fat may be a more important risk factor than visceral fat in terms of its association with metabolic syndrome.

Models for estimating the biological age of five organs using clinical biomarkers that are commonly measured in clinical practice settings

OBJECTIVES To date, no worldwide studies have been conducted to estimate the biological age of five organs using clinical biomarkers that are associated with the aging status. Therefore, we conducted this study to develop the models for estimating the biological age of five organs (heart, lung, liver, pancreas, and kidney) using clinical biomarkers which are commonly measured in clinical practice. DESIGN A cross sectional study. METHODS Subjects were recruited from the routine health check-up centers in Korea from 2004 through 2010. Data obtained from 121,189 subjects (66,168 men and 55,021 women) were used for clinical evaluation and statistical analysis. We examined the relations between clinical biomarkers associated with five organs and the chronological age and proposed a model for estimating the biological age of five organs. RESULTS In the models for predicting the biological ages of the heart, lung, liver, pancreas and kidney in men, 12, 2, 8, 3, and 5 parameters were respectively included (R(2)=0.652, 0.427, 0.107, 0.245, and 0.651). In contrast to men, 10, 2, 8, 3, and 5 parameters in women were respectively included (R(2)=0.780, 0.435, 0.140, 0.384, and 0.501). CONCLUSION We first proposed the models for predicting the biological age of five organs in the current study. We developed those using clinical parameters that can be easily obtained in clinical practice settings. Our biological age prediction models may be used as supplementary tools to assess the aging status of five organs in clinical practice settings.

Achieving recommended low density lipoprotein cholesterol goals and the factors associated with target achievement of hypercholesterolemia patients with rosuvastatin in primary care.

Abstract Objective: Hypercholesterolemia is a major risk factor for cardiovascular disease and requires continuous management. The role of primary physicians in this regard is important, yet the factors associated with successful lipid lowering treatments in primary clinics have not been clearly identified. We aimed to evaluate the rate of successful hypercholesterolemia treatment in Korean primary care, and to identify the factors associated with achieving low density lipoprotein cholesterol (LDL-C) targets. Methods: We prospectively recruited and retrospectively assessed 1851 Korean patients with hypercholesterolemia who visited family physicians and were prescribed rosuvastatin for the first time. LDL-C lowering targets, defined according to NCEP ATP III guidelines, were evaluated at 6 months after the first prescription. The factors associated with achieving these targets were also assessed. Results: Overall, 87.6% of our participants attained their LDL-C goals. In multiple logistic regression analysis, good adherence to medication was strongly associated with the achievement of target LDL-C levels, whereas higher cardiovascular risk factors including diabetes (in both sexes), low high density lipoprotein, and current smoking status (in males), and hypertension (in females) were related to LDL-C target level failures. Conclusion: Our observations of the short period for hypercholesterolemia in Korean primary care has revealed that the rate of achieving target LDL-C levels was high in these patients, whereas patients at higher risk for cardiovascular disease tended to have lower LDL-C achievement outcomes. Primary care physicians should pay more attention to patients showing higher cardiovascular risk and stress the need for good adherence and management regimens in these individuals.

The Effect of Sleep Quality on the Development of Type 2 Diabetes in Primary Care Patients

Sleep has important effects on physical and mental health, and sleep disorders are associated with increased mortality and morbidity. This study was conducted to evaluate the relationship between sleep duration or sleep quality and the risk of type 2 diabetes. The FACTS (FAmily CohorT Study in primary care) was established to investigate the relations between familial environment and health which was conducted at 22 family medicine outpatient clinics in general hospitals. Total 563 patients without diabetes who received ≥1 year follow-up examination were included in the analysis. We used the Pittsburgh Sleep Quality Index to determine sleep quality, and a score of ≥5 was considered to define poor sleep quality. Patients taking oral hypoglycemic agents, having a fasting glucose level of >126 mg/dL, or diagnosed with diabetes by physicians were classified as having diabetes. The median follow-up period was 2.5 years. Poor sleep quality was associated with a higher risk of diabetes after adjusting for age, sex, body mass index, income, physical activity, and family history of diabetes (relative risk=2.64; 95% confidence interval, 1.03-6.78). As a risk factor for the development of diabetes, poor sleep quality may independently increase the incidence of diabetes.

The Relationship between a Spouse's Alcohol Use Disorder and Family Communication

Background Alcohol use disorder (AUD) affects not only an individuals health but also their family. This study was conducted to examine effects of a spouses AUD on family functioning and family communication. Methods We conducted a cross-sectional study using data from 890 participants (445 couples) in a Korean family cohort in primary care. Participants with Alcohol Use Disorders Identification Test in Korea scores of 8 or greater were classified into an AUD group. Family functioning was classified into three groups (balanced, midrange, and extreme) using the Family Adaptability and Cohesion Scale (FACES)-III questionnaire, and then reclassified into two groups (appropriate and extreme groups) for binominal analyses. Family communication was classified into three groups (high, moderate, and low) using the Family Communication Scale, FACES-IV, and also reclassified into two groups (good and poor). Results There was no significant difference in adaptability and cohesion between both male and female participants with a spouse with AUD and participants with a spouse without AUD. Using multivariate logistic regression to adjust for potential confounders, there was no significant difference in family type and communication between the two groups in males. However, there was a significant decrease in family communication (odds ratio, 2.14; 95% confidence interval, 1.29 to 3.58) in females with a spouse with AUD compared to females with a spouse without AUD, even after adjusting for the participants own AUD. Conclusion In females, family communication is significantly worse when spouses have AUD. This suggests that a husbands alcohol consumption has negative effects on his wifes family communication.