Association of handgrip strength with new-onset CKD in Korean adults according to gender.

Introduction: Handgrip strength (HGS) is an indicator of many diseases such as pneumonia, cardiovascular disease and cancer. HGS can also predict renal function in chronic kidney disease (CKD) patients, but the value of HGS as a predictor of new-onset CKD is unknown. Methods: 173,195 subjects were recruited from a nationwide cohort and were followed for 4.1 years. After exclusions, 35,757 participants remained in the final study, and CKD developed in 1063 individuals during the follow-up period. Lifestyle, anthropometric and laboratory data were evaluated in relation to the risk of CKD. Results: The participants were subdivided into quartiles according to relative handgrip strength (RGS). Multivariate Cox regression demonstrated that RGS was inversely associated with incident CKD. Compared with the lowest quartile, the hazard ratios (HRs) [95% confidence intervals (CIs)] for incident CKD for the highest quartile (Q4) was 0.55 (0.34-0.88) after adjusting for covariates in men and 0.51 (0.31-0.85) in women. The incidence of CKD decreased as RGS increased. These negative associations were more significant in men than in women. The receiver operating characteristic (ROC) curve showed that baseline RGS had predictive power for new-onset CKD. Area under the curve (AUC) (95% CIs) was 0.739 (0.707-0.770) in men and 0.765 (0.729-0.801) in women. Conclusion: This is the novel study demonstrating that RGS is associated with incident CKD in both men and women. The relationship between RGS and incident CKD is more significant in women than in men. RGS can be used in clinical practice to evaluate renal prognosis. Regular measurement of handgrip strength is essential to CKD detection.

Association of triglyceride/high-density lipoprotein cholesterol ratio with subclinical inflammation and 10-year cardiovascular disease risk as determined by Framingham risk scores in Korean male smokers.

Various risk factors and the multifactorial pathophysiology of cardiovascular disease (CVD) have been studied. We focused on the interaction between insulin resistance and inflammatory processes. Thus, we analyzed the association of triglyceride/high-density lipoprotein cholesterol (TG/HDL) ratio with subclinical inflammation and CVD risk in male smokers. We retrospectively reviewed medical records from the Health Promotion Center of Severance Hospital in Korea between 2015 and 2017. Subjects were currently smoking men aged 30 to 59, with leukocyte counts within the normal range, for a total of 1,566. We grouped participants into four groups using the median TG/HDL ratio and the median leukocyte count. The odds ratio (OR) of high Framingham 10-year CVD risk (≥10%) was calculated using multiple logistic regression. The median Framingham 10-year CVD risk increased significantly from Group 1 (low leukocyte count, low TG/HDL ratio) to Group 4 (high leukocyte count, high TG/HDL ratio). The OR for Group 4 was 2.46 compared with Group 1 after adjusting for various CVD risk factors. In subgroup analysis, the OR of the highest leukocyte group was 1.57 compared to the lowest leukocyte group after adjusting for other variables. In conclusion, TG/HDL ratio and subclinical inflammation were positively related to CVD risk in Korean male smokers.

Fatty Liver Index as a Simple and Useful Predictor for 10-year Cardiovascular Disease Risks Determined by Framingham Risk Score in the General Korean Population.

BACKGROUND AND AIMS: The fatty liver index (FLI) is a simple and non-invasive method for the diagnosis of fatty liver disease with an increased risk of cardiovascular disease (CVD) as well as liver-related mortality. We examined the association between FLI and 10-year CVD risk as determined by the Framingham risk score. METHODS: This cross-sectional study included 7,240 individuals aged 30 to 69 years who underwent a health examination between 2015 and 2017. The FLI was calculated using an algorithm based on triglyceride, γ-glutamyltransferase, body mass index (BMI), and waist circumference. Multiple linear and logistic regression analyses were performed to assess independent relationships between the FLI and Framingham risk score after adjusting for confounding variables. RESULTS: The overall prevalence of fatty liver disease among study participants as assessed by an FLI ≥ 60 was 19.7%. Compared with non-hepatic steatosis (FLI < 30), the odds ratio (95% confidence interval) for a high Framingham 10-year CVD risk ≥ 10% in individuals with hepatic steatosis (FLI ≥ 60) was 2.56 (1.97-3.33) after adjusting for age, gender, fasting plasma glucose, high-density and low-density lipoprotein cholesterol, blood pressure, C-reactive protein, regular exercise, alcohol-drinking, and current smoking. CONCLUSIONS: The FLI was positively and independently associated with a Framingham 10-year CVD risk in the general Korean population. Our findings suggest that the FLI, a simple, useful, and economical index, may be an indicator of CVD events.

Cluster analysis of nutritional factors associated with low muscle mass index in middle-aged and older adults.

BACKGROUND & AIMS: Sarcopenia, or age-related muscle loss, is an enormous health problem in an aging world because of its many clinical and societal adverse effects. The uncovering of healthy dietary patterns is an important strategy to prevent or delay sarcopenia. We used K-means clustering to identify subgroups of men and women based on nutritional and health-related factors and investigated risk factors for low muscle mass in the subgroups and in the study population as a whole. METHODS: We analyzed a total 10,863 participants over 40 years of age who participated in the Korea National Health and Nutrition Survey from 2008 to 2011. Dual energy X-ray absorptiometry was used to determine the appendicular lean mass (ALM) of the participants. Participants with low ALM adjusted BMI (ALM/BMI) were then identified using the criteria of the Foundation for the National Institutes of Health sarcopenia project. K-means clustering and multivariate logistic regression were used to analyze associations between nutritional and health-related variables and low ALM/BMI in the population as a whole and in the individual clusters. RESULTS: A total of 712 (15.8%) men and 869 (13.7%) women had low ALM/BMI. Five clusters were identified in men and women, respectively. Two clusters of men and one cluster of women exhibited an increased risk of low ALM/BMI. Old age, low total energy intake, low levels of physical activity, and a high number of chronic diseases were consistent risk factors for low ALM/BMI in all Korean men and women. Low protein was a common risk factor for low ALM/BMI in men. After dividing all subjects by the K-means clustering algorithm, two risk factors (high fat intake and smoking) and four factors (low intakes of carbohydrate, protein and fat, and high alcohol consumption) were additionally proposed in Korean men and women, respectively. CONCLUSIONS: Age, low total energy intake, low level of physical activity, and an increased number of chronic diseases were consistent risk factors for low ALM/BMI in men and women. Cluster-specific risk factors were also noted in men and women.

Development of a suicide index model in general adolescents using the South Korea 2012-2016 national representative survey data.

Suicide is a leading cause of death among adolescents and a major public health concern. Here we developed a risk stratification model for adolescent suicide attempts using sociodemographic characteristics, risk behaviours and psychological variables. Participants were 247,222 subjects in the Korea Youth Risk Behavior Web-based Survey (KYRBS). We developed a suicide index based on the suicide risk estimated in the generalized linear model and proposed the risk stratification model using the R language to measure the probability of suicide attempt among adolescents. Among the study population, the annual rate of suicide attempt was approximately 4%. The model provided good prediction for suicide attempt (AUC = 0.85). The important univariate risk factors for the outcome were dimensional measures of age, sex, breakfast consumption, experience of violence, sleep duration, perceived stress, feeling of sadness, current cigarette smoking, current alcohol drinking, perceived general health, perceived academic record, household economic status and living with biological or adoptive parents. Our suicide index model allowed the identification of adolescents who are at a high risk for suicide. This tool may promote the prevention of adolescent suicide and can be particularly useful in everyday settings where it is difficult to contact mental health professionals immediately.

Association Between Duration of Reproductive Years and Metabolic Syndrome.

BACKGROUND: The incidence of metabolic syndrome (MetS) has gradually increased in recent years. MetS has been associated with age at menarche and menopause; however, the association between MetS and the reproductive span remains unclear. MATERIALS AND METHODS: This study examined MetS and the reproductive span among 1,214 participants of the 2014 Korea National Health and Nutrition Examination Surveys, a stratified, complex, multistage, probability cluster survey conducted by the Division of Chronic Disease Surveillance of the Korea Center for Disease Control and Prevention since 1998. MetS was defined by using the joint interim statement of the International Diabetes Federation; National Heart, Lung, and Blood Institute; and American Heart Association. The reproductive span or duration of reproductive years was calculated from age at menarche to age at menopause for postmenopausal women. RESULTS: The prevalence of MetS in this study was 36% (437 of 1,214). In multivariate analysis adjusted for age, longer reproductive years were associated with a higher prevalence of MetS (odds ratio [OR] 1.059, 95% confidence interval [CI] 1.055-1.063). However, after adjusting for covariates (age, residential area, income, dyslipidemia medication, education, current smoking, regular exercise, alcohol consumption, body mass index, years after menopause, aspartate aminotransferase, alanine aminotransferase, and white and red blood cell counts), longer reproductive years were associated with a lower prevalence of MetS (OR 0.751, 95% CI 0.745-0.747). CONCLUSION: Longer reproductive years were significantly associated with a decreased prevalence of MetS.

Correlation between Abnormal Pap Smear Finding and Brachial-ankle Pulse Wave Velocity in Korean Women.

BACKGROUND: Cervical cancer is caused by chronic human papilloma virus (HPV) infection. Pap smear is very efficient examination for early detecting cervical cancer. Inflammation reaction due to chronic infection is one of the major causes of atherosclerosis. Pulse wave velocity (PWV) is commonly used in predicting subclinical atherosclerosis. But no study was done about correlation between cervical cancer and PWV. METHODS: The research population, 1,779 people, had been chosen from the patients from Jan. 1st, 2008 to December 31st, 2010, visited health exam center who had done both PWV test and pap smear without any medical history of obstetrics and gynecological disease. The group was divided into two respective groups, 45 people with abnormal finding and 228 people with normal finding. The correlation was analyzed between risk factor of cervical cancer and brachial-ankle PWV. Multiple regression analysis was performed with associated variables. RESULTS: Average PWV of normal group was 1,313.06 ± 264.19 and 1,497.15 ± 359.58 was for abnormal. The PWV of abnormal group was statistically significant (p = 0.0006) with association between risk factors of cervical cancer and PWV, age, height, weight, income, gravidity. Multiple regression was done with correcting these variables. PWV was associated with abnormal Pap smear but result, were not found to be significant (p = 0.054). CONCLUSION: The result was not statistically confident but more mass studies are needed to correcting those limitation.

Association between short sleep duration and high incidence of metabolic syndrome in midlife women.

Chronic sleep deprivation is increasingly common in industrialized societies. Short sleep duration has been associated with a number of negative health outcomes. The objectives of this study were to investigate the association between self-reported sleep duration and the presence of metabolic syndrome (combination of central obesity, triglyceride, high density lipoprotein, blood pressure, fasting plasma glucose) in adults during midlife. The Korean Genomic Rural Cohort (KGRC) is a cohort study of aged 40 to 70 years in rural Korea. This study focuses on the prevalence, incidence, and risk factors for chronic degenerative disorders, such as hypertension, diabetes, osteoporosis, respiratory diseases, and metabolic syndrome. The baseline sample of participants in the KGRC study was recruited in 2005-2006 (phase 1). Respondents were followed until 2008-2009 (phase 2). The final sample included 1,107 subjects: 386 males (34.9%) and 721 females (65.1%). The incidence rate of metabolic syndrome in our sample was 18.4% (21.2% for males and 16.9% for females). Subjects sleeping < 6 hours a day (HR: 1.798; 95% CI: 1.06-3.05) were significantly more likely to experience metabolic syndrome than participants sleeping 6 to 7.9 hours a day after controlling for potential covariates (age, body mass index, menopause, smoking, alcohol and physical activity). Shorter sleep duration was associated with the high incidence of metabolic syndrome among females only. In conclusion, shorter sleep duration may be a significant risk factor for the development of metabolic syndrome in women.

The clustering patterns of metabolic risk factors and its association with sub-clinical atherosclerosis in Korean population.

BACKGROUND AND AIMS: Metabolic syndrome (MetS) is considered to be an insulin-resistance syndrome, but recent evidence suggests that MetS has multiple physiological origins which may be related to atherosclerosis. This study investigated clustering patterns of metabolic risk factors and its association with sub-clinical atherosclerosis. SUBJECTS AND METHODS: This study used factor analysis of 11 metabolic factors in 1374 individuals to define clustering patterns and determine their association with carotid intima-media thickness (CIMT). Eleven metabolic factors were used: body mass index (BMI), waist circumference (WC), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG), fasting blood insulin (FBI), serum triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), homeostasis model assessment-insulin resistance (HOMA-IR), high-sensitivity C-reactive protein (hsCRP) and adiponectin. Two regression analyses were done, the first using individual metabolic variables and the second using each factor from the factor analysis to evaluate their relationships with CIMT. RESULTS: Four clustering patterns, insulin-resistance factor (FBG, FBI, HOMA-IR), obesity-inflammatory factor (BMI, WC, hsCRP), blood pressure factor (SBP, DBP) and lipid metabolic factor (HDL-C, TG, adiponectin) were categorized. In a multivariate regression model after adjustment for age, sex, low-density lipoprotein cholesterol and smoking history (pack year), insulin resistance factor (B = 11.09, p = 0.026), obesity-inflammatory factor (B = 18.50, p < 0.001), blood pressure factor (B = 12.84, p = 0.010) and lipid metabolic factor (B = - 11.55, p = 0.023) were found to be significantly associated with CIMT. CONCLUSION: In conclusion, metabolic risk factors have four distinct clustering patterns that are independently associated with sub-clinical atherosclerosis.

Relationship between white blood cell count and nonalcoholic fatty liver disease.

BACKGROUND: Higher levels of white blood cell (WBC) count are known to be associated with metabolic syndrome and insulin resistance. Nonalcoholic fatty liver disease (NAFLD) is also considered a hepatic manifestation of insulin resistance. AIMS: The present study aimed to determine the relation between WBC count and the presence of NAFLD based on abdominal sonographic findings. METHODS: A cross-sectional study with 3681 healthy subjects (2066 men, 1615 women) undergoing medical check-up was conducted. The odds ratios (ORs) and 95% confidence intervals (CIs) for NAFLD were calculated using multivariate logistic regression analyses across WBC quartiles. RESULTS: A graded independent relationship between higher levels of WBC count and the prevalence risk of NAFLD was observed. After adjusting for age, smoking status, regular exercise, body mass index (BMI), blood pressure, fasting plasma glucose, triglyceride, and HDL-cholesterol, the ORs (95% CIs) for NAFLD according to WBC quartiles were 1.00, 1.48 (1.10-1.98), 1.59 (1.18-2.14), and 1.84 (1.35-2.51) for men and 1.00, 1.15 (0.67-1.96), 1.88 (1.13-3.11), and 2.74 (1.68-4.46) for women. CONCLUSIONS: WBC count was found to be independently associated with the presence of NAFLD regardless of classical cardiovascular risk factors and other components of metabolic syndrome.

Gender difference and determinants of C-reactive protein level in Korean adults.

BACKGROUND: C-reactive protein (CRP) has emerged as an important predictor for cardiovascular disease (CVD). To facilitate clinical and public health interventions, CRP thresholds have been defined as follows: low-risk (<1.0 mg/L), average-risk (1.0-3.0 mg/L), and high-risk (>3.0 mg/L). However, these cut-off thresholds are based on distributions in Western populations, and do not distinguish between men and women. METHODS: We examined CRP distribution, gender difference, and determinants of CRP concentrations ranging from 0.02 mg/L to 10.0 mg/L, in 4923 Korean adults (2248 men; 2675 women) who received health checkups at Gangnam Severance Hospital from March 2006 to May 2007. RESULTS: The distribution of CRP was highly skewed toward lower concentrations. CRP was higher in men than women, and the cut-off thresholds for the high-risk tertile of CRP concentrations corresponded to 1.01 mg/L in men and 0.62 mg/L in women, based on the current study population. Age, male gender, cigarette smoking, physical activity, body mass index, total cholesterol, high density lipoprotein cholesterol, gamma-glutamyltransferase, and uric acid were independently associated with CRP concentrations. CONCLUSIONS: CRP distribution and gender difference in Korean adults were found to be different from previous Western studies, although similar risk factors influence CRP concentrations. Our results suggest that ethnicity and gender specific cut-off thresholds for CRP concentrations should be taken into consideration in CVD risk assessment.

Elevated white blood cell count is associated with arterial stiffness.

BACKGROUND AND AIMS: White blood cell (WBC) count, a usual marker of systemic inflammation, is known to be associated with atherosclerotic cardiovascular disease. The aim of the present study was to determine the association of WBC count with arterial stiffness measured by brachial-ankle pulse wave velocity (baPWV). METHODS AND RESULTS: We examined the association between WBC count and baPWV in 788 Korean adults (375 men, 413 women) in a health examination program. The odds ratios for a high baPWV were calculated using multivariate logistic regression analysis after adjusting for confounding variables across WBC count quartiles (Q1: or=7320 cells/mm(3)). A high baPWV was defined as more than 1440 cm/s (>75th percentile). Age-adjusted baPWV mean values gradually increased with WBC quartiles (Q1=1294, Q2=1322, Q3=1347, and Q4=1367 cm/s). The odds ratios (95% CI) for a high baPWV in each WBC count quartile were 1.00, 1.34 (0.61-3.00), 2.20 (0.96-5.06), and 2.69 (1.15-6.47) after adjusting for age, sex, cigarette smoking, alcohol intake, regular exercise, body mass index (BMI), mean arterial blood pressure, fasting plasma glucose, triglyceride, HDL-cholesterol, gamma-glutamyltransferase (GGT), and uric acid. CONCLUSION: These findings indicate that elevated WBC count is associated with arterial stiffness. Accordingly, early detection of an elevated WBC count is important for arterial function and the assessment of cardiovascular risk.

Association of serum gamma-glutamyltransferase with C-reactive protein levels and white blood cell count in Korean adults.

BACKGROUND: Elevated gamma-glutamyltransferase (GGT) has emerged as an independent predictor of cardiovascular disease (CVD) which is increasingly viewed as an inflammatory disease. Thus, the mechanism underlying the link between elevated GGT and CVD may be inflammation. METHODS: We examined the relationship between GGT and C-reactive protein (CRP) levels and white blood cell (WBC) count in 4562 Korean adults (2104 men, 2458 women). The odds ratio (OR) and 95% confidence interval (CI) for high CRP and WBC count (> or = 75th percentile) for both men and women were calculated across each quartile of serum GGT. RESULTS: Results for the OR (95% CI) for high CRP levels by GGT quartiles were 1.00, 1.67 (1.21-2.29), 2.10 (1.51-2.93) and 2.51 (1.81-3.60) in men, and 1.00, 1.05 (0.65-1.68), 1.45 (0.79-2.02) and 2.16 (1.37-3.41) in women after adjustment for age, smoking status, alcohol intake, exercise, body mass index, blood pressure, fasting plasma glucose, triglyceride, high-density lipoprotein-cholesterol, and uric acid. Similarly, positive associations between serum GGT and WBC count were also observed. CONCLUSIONS: The present study demonstrates a positive correlation between GGT and two markers of inflammation, serum CRP and WBC count. Our findings suggest that serum GGT may be a surrogate inflammatory marker and a useful additional measure in assessing cardiovascular risk.