Development and Validation of Osteoporosis Risk-Assessment Model for Korean Men

PURPOSE: The aim of the present study was to develop an osteoporosis risk-assessment model to identify high-risk individuals among Korean men. MATERIALS AND METHODS: The study used data from 1340 and 1110 men > or =50 years who participated in the 2009 and 2010 Korean National Health and Nutrition Examination Survey, respectively, for development and validation of an osteoporosis risk-assessment model. Osteoporosis was defined as T score < or =-2.5 at either the femoral neck or lumbar spine. Performance of the candidate models and the Osteoporosis Self-assessment Tool for Asian (OSTA) was compared with sensitivity, specificity, and area under the receiver operating characteristics curve (AUC). A net reclassification improvement was further calculated to compare the developed Korean Osteoporosis Risk-Assessment Model for Men (KORAM-M) with OSTA. RESULTS: In the development dataset, the prevalence of osteoporosis was 8.1%. KORAM-M, consisting of age and body weight, had a sensitivity of 90.8%, a specificity of 42.4%, and an AUC of 0.666 with a cut-off score of -9. In the validation dataset, similar results were shown: sensitivity 87.9%, specificity 39.7%, and AUC 0.638. Additionally, risk categorization with KORAM-M showed improved reclassification over that of OSTA up to 22.8%. CONCLUSION: KORAM-M can be simply used as a pre-screening tool to identify candidates for dual energy X-ray absorptiometry tests.

Association between Fibrinogen and Carotid Atherosclerosis According to Smoking Status in a Korean Male Population

PURPOSE: Although inconsistent, reports have shown fibrinogen levels to be associated with atherosclerosis. Accordingly, since cigarette smoking is associated with increased levels of fibrinogen and atherosclerosis, it may also affect the association between fibrinogen and atherosclerosis. We investigated the associations between fibrinogen and carotid intima-media thickness (IMT) according to smoking status in a Korean male population. MATERIALS AND METHODS: Plasma fibrinogen levels were measured in 277 men aged 40-87 years without a history of myocardial infarction or stroke. High-resolution B-mode ultrasonography was used to examine the common carotid arteries. IMT level was analyzed both as a continuous (IMT-max, maximum value; IMT-tpm, 3-point mean value) and categorical variable (higher IMT; presence of plaque). Serial linear and logistic regression models were employed to examine the association between fibrinogen and IMT according to smoking status. RESULTS: Fibrinogen levels were positively associated with IMT-max (standardized beta=0.25, p=0.021) and IMT-tpm (standardized beta=0.21, p=0.038), even after adjusting for age, body mass index, systolic blood pressure, fasting glucose, and total cholesterol to high-density lipoprotein cholesterol ratio in current smokers (n=75). No significant association between fibrinogen and IMT, however, was noted in former smokers (n=80) or nonsmokers (n=122). Adjusted odds ratios (95% confidence interval) for having plaque per one standard deviation higher fibrinogen level were 2.06 (1.09-3.89) for current smokers, 0.68 (0.43-1.10) for former smokers, and 1.06 (0.60-1.87) for nonsmokers. CONCLUSION: Our findings suggest that cigarette smoking may modify the association between fibrinogen and carotid atherosclerosis. Further studies are required to confirm this finding in different populations.

Association between Serum 25-Hydroxyvitamin D Level and Insulin Resistance in a Rural Population

PURPOSE: A low serum 25-hydroxyvitamin D [25(OH)D] level in the blood has been correlated with an increased risk of diabetes mellitus; however, the association between serum 25(OH)D level and insulin resistance has not been established in a Korean rural population. The aim of this study was to investigate the independent association between serum 25(OH)D level and insulin resistance in rural Korean adults. MATERIALS AND METHODS: This study used data from the Korean Genome Epidemiology Study-Kangwha Study. In the 2011 study, 1200 adults completed health examinations. In an ancillary study, serum 25(OH)D level was measured in a subsample (n=813). After excluding those taking vitamin D supplements, a cross-sectional analysis was carried out on 807 participants (324 men and 483 women) aged 40 to 89 years old. Measured from overnight fasting blood samples, glucose and insulin levels were used to calculate the homeostasis model assessment for insulin resistance (HOMA-IR). Measures of glucose, insulin, and HOMA-IR were log-transformed for parametric tests. RESULTS: Serum 25(OH)D level was inversely associated with HOMA-IR (beta=-0.003, p=0.039) in a univariate analysis. However, the association was not significant after adjustment for sex and age (beta=-0.002, p=0.123) or after adjustment for sex, age, body mass index, smoking status, alcohol intake, and regular exercise (beta=-0.003, p=0.247). CONCLUSION: Our findings suggest that vitamin D is not independently associated with insulin resistance in Korean men and women.

Development and Application of Chronic Disease Risk Prediction Models

Currently, non-communicable chronic diseases are a major cause of morbidity and mortality worldwide, and a large proportion of chronic diseases are preventable through risk factor management. However, the prevention efficacy at the individual level is not yet satisfactory. Chronic disease prediction models have been developed to assist physicians and individuals in clinical decision-making. A chronic disease prediction model assesses multiple risk factors together and estimates an absolute disease risk for the individual. Accurate prediction of an individual's future risk for a certain disease enables the comparison of benefits and risks of treatment, the costs of alternative prevention strategies, and selection of the most efficient strategy for the individual. A large number of chronic disease prediction models, especially targeting cardiovascular diseases and cancers, have been suggested, and some of them have been adopted in the clinical practice guidelines and recommendations of many countries. Although few chronic disease prediction tools have been suggested in the Korean population, their clinical utility is not as high as expected. This article reviews methodologies that are commonly used for developing and evaluating a chronic disease prediction model and discusses the current status of chronic disease prediction in Korea.

Development and Application of Chronic Disease Risk Prediction Models

Currently, non-communicable chronic diseases are a major cause of morbidity and mortality worldwide, and a large proportion of chronic diseases are preventable through risk factor management. However, the prevention efficacy at the individual level is not yet satisfactory. Chronic disease prediction models have been developed to assist physicians and individuals in clinical decision-making. A chronic disease prediction model assesses multiple risk factors together and estimates an absolute disease risk for the individual. Accurate prediction of an individual's future risk for a certain disease enables the comparison of benefits and risks of treatment, the costs of alternative prevention strategies, and selection of the most efficient strategy for the individual. A large number of chronic disease prediction models, especially targeting cardiovascular diseases and cancers, have been suggested, and some of them have been adopted in the clinical practice guidelines and recommendations of many countries. Although few chronic disease prediction tools have been suggested in the Korean population, their clinical utility is not as high as expected. This article reviews methodologies that are commonly used for developing and evaluating a chronic disease prediction model and discusses the current status of chronic disease prediction in Korea.

Factors Associated with a Low-sodium Diet: The Fourth Korean National Health and Nutrition Examination Survey / 한국역학회지

OBJECTIVES: The low-sodium diet is a known preventive factor for hypertension and cardiovascular disease. Factors associated with low-sodium diets should be identified to reduce sodium intake effectively. This study was conducted to identify factors correlated with a low-sodium diet. METHODS: This cross-sectional study analyzed data from a total of 14,539 Koreans aged 20 years or older, who participated in the Fourth (2007-2009) Korean National Health and Nutrition Examination Survey. A low-sodium diet was defined as having or =1 time/day, respectively. CONCLUSIONS: Our study suggests that sex, age, number of family members, occupation, total energy intake, and lower frequency of eating out were associated with a low-sodium diet in Korean adults.

Erratum: Correction of Title. Longitudinal Standards for Height and Height Velocity in Korean Children and Adolescents: the Kangwha Cohort Study

We found an title error in our published article.

Noncommunicable Diseases: Current Status of Major Modifiable Risk Factors in Korea / 예방의학회지

A noncommunicable disease (NCD) is a medical condition or disease that is by definition non-infectious and non-transmissible among people. Currently, NCDs are the leading causes of death and disease burden worldwide. The four main types of NCDs, including cardiovascular disease, cancer, chronic lung disease, and diabetes, result in more than 30 million deaths annually. To reduce the burden of NCDs on global health, current public health actions stress the importance of preventing, detecting, and correcting modifiable risk factors; controlling major modifiable risk factors has been shown to effectively reduce NCD mortality. The World Health Organization's World Health Report 2002 identified tobacco use, alcohol consumption, overweight, physical inactivity, high blood pressure, and high cholesterol as the most important risk factors for NCDs. Accordingly, the present report set out to review the prevalence and trends of these modifiable risk factors in the Korean population. Over the past few decades, we observed significant risk factor modifications of improved blood pressure control and decreased smoking rate. However, hypertension and cigarette smoking remained the most contributable factors of NCDs in the Korean population. Moreover, other major modifiable risk factors show no improvement or even worsened. The current status and trends in major modifiable risk factors reinforce the importance of prevention, detection, and treatment of risk factors in reducing the burden of NCDs on individuals and society.

Longitudinal Standards for Height and Height Velocity in Korean Children and Adolescents: the Kangwha Cohort Study

Longitudinal standards for height and height velocity are essential to monitor for appropriate linear growth. We aimed to construct standards in Korean children and adolescents through the population-based longitudinal Kangwha study. Our study was a part of a community-based prospective cohort study from 1986 to 1999 with 800 school children. Height and height velocity were recorded annually from age 6 until final height. Results were compared with cross-sectional data from the 2007 Korean National Growth Charts. Final height was 173.5 cm in boys and 160.5 cm in girls. Although final height was similar between longitudinal and cross-sectional standards, the mean height for age was higher in the longitudinal standard by 1-4 cm from age 6 until the completion of puberty. Using the longitudinal standard, age at peak height velocity (PHV) was 12 in boys and 10 in girls; height velocity at PHV was 8.62 cm/yr in boys and 7.07 cm/yr in girls. The mean height velocity was less than 1 cm/yr at age 17 in boys and 15 in girls. Thus, we have presented the first report of longitudinal standards for height and height velocity in Korean children and adolescents by analyzing longitudinal data from the Kangwha cohort.

The Association Between Serum Albumin Levels and Metabolic Syndrome in a Rural Population of Korea / 예방의학회지

OBJECTIVES: A positive association between serum albumin levels and metabolic syndrome has been reported in observation studies, but it has not been established in the Korean population. The purpose of this study was to evaluate the association between serum albumin levels and the presence of metabolic syndrome among a sample of apparently healthy Korean adults. METHODS: This cross-sectional study analyzed data of 3189 community-dwelling people (1189 men and 2000 women) who were aged 40 to 87 years and were living in a rural area in Korea. Serum albumin levels were classified into quartile groups for each sex. Metabolic syndrome was defined according to the National Cholesterol Education Program Adult Treatment Panel III guidelines with an adjusted waist circumference cut-off value (> or =90 cm for men and > or =85 cm for women). An independent association between serum albumin levels and metabolic syndrome was assessed by multiple logistic regression analysis. RESULTS: Higher serum albumin levels were associated with increased prevalence of metabolic syndrome. The odds ratio (95% confidence interval) of the prevalence of metabolic syndrome for the highest versus the lowest serum albumin quartiles was 2.81 (1.91 to 4.14) in men and 1.96 (1.52 to 2.52) in women, after adjusting for age, smoking status, alcohol consumption, and physical activity. When each metabolic abnormality was analyzed separately, higher serum albumin levels were significantly associated with hypertriglyceridemia and hyperglycemia in both sexes, and with abdominal obesity in men. CONCLUSIONS: These results suggest that higher serum albumin levels are positively associated with an increased risk of metabolic syndrome in Korean adults.

Association Between Serum Uric Acid Level and Metabolic Syndrome / 예방의학회지

OBJECTIVES: Serum uric acid levels have been reported to be associated with a variety of cardiovascular conditions. However, the direct association between uric acid levels and metabolic syndrome remains controversial. Thus, we evaluated the association of serum uric acid levels and metabolic syndrome in a community-based cohort study in Korea. METHODS: We performed cross-sectional analysis of baseline data of 889 males and 1491 females (aged 38 to 87) who participated in baseline examinations of the Korean Genome and Epidemiology Study: Kanghwa study. Blood samples were collected after at least an 8 hour fast. Uric acid quartiles were defined as follows: or =6.5 mg/dL in males; and or =5.1 mg/dL in females. Metabolic syndrome was defined by the National Cholesterol Education Program Adult Treatment Panel III Criteria with adjusted waist circumference cutoffs (90 cm for males; 80 cm for females). The association between serum uric acid quartiles and metabolic syndrome was assessed using multivariate logistic regression. RESULTS: The odds ratio for having metabolic syndrome in the highest versus lowest quartiles of serum uric acid levels was 2.67 (95% confidence interval [CI], 1.60 to 4.46) in males and 2.14 (95% CI, 1.50 to 3.05) in females after adjusting for age, smoking, alcohol intake, body mass index, total cholesterol, HbA1c, albumin, gamma-glutamyltransferase, blood urea nitrogen, and log C-reactive protein. The number of metabolic abnormalities also increased gradually with increasing serum uric acid levels (adjusted p for trend < 0.001 in both sexes). CONCLUSIONS: Higher serum uric acid levels are positively associated with the presence of metabolic syndrome in Korean males and females.

Association Between Meat Consumption and Carotid Intima-Media Thickness in Korean Adults with Metabolic Syndrome / 예방의학회지

OBJECTIVES: The effect of meat consumption on cardiometabolic risk has been continuously studied, but their associations are not conclusive. The aim of this study is to examine the association between the consumption of meat or red meat and carotid intima-media thickness (IMT) in healthy Korean adults. METHODS: This study evaluated 2374 community-dwelling adults (933 men and 1441 women) who were free of cardiovascular disease or cancer, living in a rural area in Korea. Total meat and red meat intakes were assessed with a validated 103 item-food frequency questionnaire. Carotid IMT was evaluated ultrasonographically, IMTmax was defined as the highest value among IMT of bilateral common carotid arteries. RESULTS: After adjustment for potential confounding factors, the mean IMTmax tended to increase in higher meat consumption groups in both men and women with metabolic syndrome (p for trend= 0.027 and 0.049, respectively), but not in participants without metabolic syndrome. Frequent meat consumption (> or =5 servings/week) was significantly associated with higher IMTmax in men with metabolic syndrome (by 0.08 mm, p=0.015). Whereas, the association was not significant in women (by 0.05 mm, p=0.115). Similar but attenuated findings were shown with red meat intake. CONCLUSIONS: Our findings suggest that a higher meat consumption may be associated with a higher carotid IMT in Korean adults with metabolic syndrome. The frequent meat consumption (> or =5 servings/week), compared with the others, was associated with a higher carotid IMTmax only in men with metabolic syndrome. Further research is required to explore optimal meat consumption in people with specific medical conditions.