One author's name is misspelled. Correct Seungho Rhu into Seungho Ryu.

Objectives: The aim of this retrospective cohort study was to investigate whether non-alcoholic fatty liver disease (NAFLD) was associated with incident bone mineral density (BMD) decrease. Methods: This study included 4536 subjects with normal BMD at baseline. NAFLD was defined as the presence of fatty liver on abdominal ultrasonography without significant alcohol consumption or other causes. Decreased BMD was defined as a diagnosis of osteopenia, osteoporosis, or BMD below the expected range for the patient’s age based on dual-energy X-ray absorptiometry. Cox proportional hazards models were used to estimate the hazard ratio of incident BMD decrease in subjects with or without NAFLD. Subgroup analyses were conducted according to the relevant factors. Results: Across 13 354 person-years of total follow-up, decreased BMD was observed in 606 subjects, corresponding to an incidence of 45.4 cases per 1000 person-years (median follow-up duration, 2.1 years). In the model adjusted for age and sex, the hazard ratio was 0.65 (95% confidence interval, 0.51 to 0.82), and statistical significance disappeared after adjustment for body mass index (BMI) and cardiometabolic factors. In the subgroup analyses, NAFLD was associated with a lower risk of incident BMD decrease in females even after adjustment for confounders. The direction of the effect of NAFLD on the risk of BMD decrease changed depending on BMI category and body fat percentage, although the impact was statistically insignificant. Conclusions NAFLD had a significant protective effect on BMD in females. However, the effects may vary depending on BMI category or body fat percentage.

It remains unclear as to whether insulin resistance alone or in the presence of wellknown risk factors, such as diabetes or obesity, is associated with gallstones in men. The aim of this study was to determine whether insulin resistance is associated independently with gallstone disease in non-diabetic men, regardless of obesity. Study subjects were 19,503 Korean men, aged 30-69 yr, with fasting blood glucose level <126 mg/dL and without a documented history of diabetes. Gallbladder status was assessed via abdominal ultrasonography after overnight fast. Body mass index and waist circumference were measured. Insulin resistance was estimated by the Homeostasis Model Assessment of insulin resistance (HOMA-IR). The prevalence of obesity, abdominal obesity, and metabolic syndrome in the subjects with gallstones were higher than in those without. The prevalence of elevated HOMA (>75 percentile) in subjects with gallstones was significantly higher than in those without, and this association remained even after the obesity stratification was applied. In multiple logistic regression analyses, only age and HOMA proved to be independent predictors of gallstones. Insulin resistance was positively associated with gallstones in non-diabetic Korean men, and this occurred regardless of obesity. Gallstones appear to be a marker for insulin resistance, even in non-diabetic, nonobese men.
Adult ; Aged ; Aged, 80 and over ; Body Mass Index ; Gallstones/*etiology ; Humans ; *Insulin Resistance ; Logistic Models ; Male ; Middle Aged ; Obesity/complications ; Risk Factors

The aim of this study was to examine the association between serum apolipoprotein B (apoB) and the risk of coronary heart disease (CHD) using Framingham risk score (FRS) in healthy Korean men. A total of 13,523 men without medication history of diabetes and hypertension were enrolled in this study. The FRS is based on six coronary risk factors. FRS > or = 10% was defined as more-than-a-moderate risk group and FRS > or = 20% as high risk group, respectively. The logistic regression analyses were conducted. When quartile 1 (Q1) set as a reference, in unadjusted analyses, the Q2, Q3, Q4 of apoB level had increased odds ratio (OR) for the risk of CHD in both more-than-a-moderate risk and high risk group, respectively. After adjusting for confounding variables, multivariable-adjusted logistic regression analyses showed a strong relationship between the quartiles of apoB level and more-than-a-moderate risk and high risk group, respectively. These associations were attenuated, but still remained statistically significant. ApoB is found to be independently related to the risk of CHD using FRS in healthy Korean men, and the link between apoB and the risk of CHD is dose-depedent.
Adult ; Apolipoproteins B/*blood ; Coronary Disease/*blood/*diagnosis ; Humans ; Male ; Men's Health ; Middle Aged ; Odds Ratio ; Republic of Korea ; Risk Assessment ; Risk Factors

OBJECTIVES: Obesity is considered to be one of the most important risk factors for obstructive sleep apnea (OSA) but less is known about the role of ethnicity in OSA. The purpose of this study was to investigate the interethnic difference of obesity-related phenotypes in OSA and to reveal the role of ethnicity in OSA. METHODS: We searched MEDLINE, LILACS, Scopus, and the Cochrane Library using the key words "sleep apnea," "body mass index," "neck circumference," "waist circumference," "waist to hip ratio," etc. Inclusion criteria were adults over 18 years of age, and studies that included polysomnography, obesity-related parameters, and a clear demarcation of ethnicity in the patient population. Included studies were reviewed by 2 independent reviewers. The following information was collected for controls and OSA: number, age, gender, country, ethnicity (Asian or Caucasian), study design, apnea-hypopnea index/respiratory disturbance index, body mass index (BMI), neck circumference (NC), waist circumference (WC), and/or waist to hip ratio (WHR). RESULTS: A total of 8,312 publications were retrieved with a subsequent 19 manuscripts that met the selection criteria. A total of 2,966 patients were included for analysis. The main findings were as follows: There was no difference in BMI, WC, and WHR between patients with OSA and controls after accounting for publication bias; Patients with OSA have greater NC than controls (standard mean difference, 0.89; 95% confidence interval, 0.63 to 1.14); and There was no difference in NC between Asian and Caucasians patients (P=0.178). CONCLUSION: OSA might not be related with BMI, WC, and WHR. Only NC demonstrated a strong association with OSA, and this finding was not different between Asians and Caucasians.
Adult ; Asian Continental Ancestry Group* ; Body Mass Index ; Hip ; Humans ; Neck ; Obesity ; Patient Selection ; Phenotype ; Polysomnography ; Publication Bias ; Risk Factors ; Sleep Apnea, Obstructive* ; Waist Circumference ; Waist-Hip Ratio

BACKGROUND AND OBJECTIVES: This study was carried out to investigate a suspected high prevalence of WRUEMSD (Work related upper-extremity musculoskeletal disorders) in the visual display terminal (VDT) operators of a major telecommunication company in Seoul, Korea. METHOD: The severity of the disorders was assessed by both medical screening examination and questionnaires. All the operators involved in the study were using VDT. A self-administered questionnaire, designed to obtain demographic information, individual factors, and musculoskeletal symptoms of the various body parts was distributed to participating operators. RESULTS: A total of 888 female directory assistance operators (average age 39.7+/-4.6 years old) working at three companies participated in the study. The task was machinepaced, as customer calls were routed to available operators by computer. The number of the workers requiring treatment when symptoms aggravated was 384 (43.2%), and that of the workers needing treatment was 173 (19.5%). WRUEMSD of neck was associated with working during rest time (Odds ratio=1.59), partial finger users (OR=1.87), and that of hand/wrist was associated with adjustability of the height of the chair. CONCLUSION: The prevalence of WRUEMSD in the VDU operators of the a major telecommunication company was high. Current issues and suggestions for future ergonomic studies are addressed.
Female ; Fingers ; Human Body ; Humans ; Korea* ; Mass Screening ; Neck ; Prevalence ; Seoul* ; Telecommunications* ; Surveys and Questionnaires

BACKGROUND: Previous studies have reported the effects of direction of shift rotation on sleep, however, the findings are inconsistent. In this study, we investigated sleep quality related to direction of shift rotation using large-scale data from shiftwork-specific health examinations of electronics workers. METHODS: This study included 4750 electronics workers working in a rotating 3-shift system who completed a medical examination for shift workers survey from January 1 to December 31, 2014, at a general hospital. The subjects were categorized into one of two groups according to direction of shift rotation. We compared sleep quality index between the subjects who worked in forward rotation and backward rotation systems. RESULTS: Backward rotation was positively associated with prevalence of poor sleep quality. In the multivariable-adjusted model, when comparing backward rotation to forward rotation, the odds ratio (OR) with 95 % confidence interval (95 % CI) for poor sleep quality was 1.95 (1.58–2.41). After stratifying by gender, the ORs (95 % CIs) for poor sleep quality in male and female was 1.92 (1.47–2.49) and 2.13 (1.47–3.08), respectively. In subgroup analyses, backward rotation was significantly associated with poor sleep quality in workers ≥30 years of age compared with workers <30 years of age (adjusted OR 2.60 vs. 1.89, respectively; P for interaction <0.001). CONCLUSIONS: Our study supports that a backward rotation system is associated with poor sleep quality. Forward rotation systems should be considered to reduce sleep problems.
Female ; Hospitals, General ; Humans ; Male ; Odds Ratio ; Prevalence

OBJECTIVES: This study was performed to assess the level of job and psychosocial stresses in Korean firefighters, and to evaluate the determinants of psychosocial stress. METHODS: The study subjects comprised 1,712 male firefighters working in Seoul, Busan, and Kyungnam in 2006. We collected information about demographic and job-related characteristics, healthrelated behaviors, Korean Occupational Stress Scale (KOSS), and psychosocial Well-being Index (PWI) through self-administered questionnaires. Statistical analyses were done by using the chi-square-test and logistic regression model. RESULTS: The multiple logistic regression analyses indicated that the proportion of high-risk psychosocial stress is significantly higher in the groups with high job stress level in 'lack of rewards' (OR=2.90, 95% CI=2.18-3.85), 'occupational climate' (OR=1.92, 95% CI=1.47-2.51), 'job demand' (OR=1.72, 95% CI=1.32-2.23), 'job insecurity' (OR=1.53, 95% CI=1.17-2.01), 'interpersonal conflict' (OR=1.53, 95% CI=1.16-2.01), 'physical environment' (OR=1.45, 95% CI=1.11-1.89), and 'organizational injustice' (OR=1.38, 95% CI=1.04-1.85). CONCLUSIONS: Psychosocial stress might be adversely influenced by job stressors for the most part. Firefighters need job stress management to minimize their psychological problems.
Firefighters ; Humans ; Logistic Models ; Male ; Questionnaires

BACKGROUND: In this study, we investigated whether lobetyolin, lobetyol, and methyl linoleate derived from Codonopsis pilosula affect MUC5AC mucin secretion, production, and gene expression from airway epithelial cells. METHODS: Confluent NCI-H292 cells were pretreated with lobetyolin, lobetyol, or methyl linoleate for 30 minutes and then stimulated with phorbol 12-myristate 13-acetate (PMA) for 24 hours. The MUC5AC mucin gene expression, and mucin protein production and secretion were measured by reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. RESULTS: Lobetyolin, lobetyol, and methyl linoleate inhibited the gene expression of MUC5AC mucin induced by PMA; lobetyolin did not affect PMA-induced MUC5AC mucin production. However, lobetyol and methyl linoleate inhibited the production of MUC5AC mucin; lobetyolin and lobetyol did not significantly affect PMA-induced MUC5AC mucin secretion from NCI-H292 cells. However, methyl linoleate decreased the MUC5AC mucin secretion. CONCLUSION: These results suggest that among the three compounds, methyl linoleate can regulate gene expression, production, and secretion of MUC5AC mucin by directly acting on the airway epithelial cells.
Codonopsis ; Enzyme-Linked Immunosorbent Assay ; Epithelial Cells* ; Gene Expression* ; Linoleic Acid* ; Mucins* ; Polymerase Chain Reaction ; Reverse Transcription

BACKGROUND/AIMS: The prevalence of nonalcoholic fatty liver disease (NAFLD) in Korea has increased recently. The aim of the present study was to determine the regional differences in the prevalence and characteristics of NAFLD. METHODS: From January 2009 to December 2010, 161,891 Seoul and Gyeonggi-do residents receiving a health examination at our institution were enrolled in this cross-sectional study. After applying exclusion criteria, the data of 141,610 subjects (80,943 males, 60,667 females) were analyzed. The presence of NAFLD was established by ultrasound examination. RESULTS: The overall prevalence of NAFLD was 27.3% (38.3% in men, 12.6% in women). When standardized according to age, area, and sex, the prevalence of NAFLD was 25.2%. The age and area standardized prevalence of NAFLD was higher for men (34.4%) than for women (12.2%; P<0.001). The overall prevalence of NAFLD was higher in Gyeonggi-do (27.7%) than in Seoul (26.9%; P<0.001). Among the men, the prevalence of NAFLD was higher in Gyeonggi-do (39.2%) than in Seoul (37.4%; P<0.001), while for the women it was higher in Seoul (13.2%) than in Gyeonggi-do (12.0%; P<0.001). CONCLUSIONS: The regional prevalence of NAFLD differed between Seoul and Gyeonggi-do. Further studies are needed to establish the etiology of this difference.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Cross-Sectional Studies ; Fatty Liver/*epidemiology/etiology/ultrasonography ; Female ; Humans ; Male ; Middle Aged ; Prevalence ; Republic of Korea/epidemiology ; Young Adult