Korean Male Workers Research Articles

사회심리적 작업환경이 문제음주에 미치는 영향: 연령 차이

Purpose: This study firstly examined the pattern and prevalence of drinking. Secondly, we investigated the association between various psychosocial work environment and problem drinking among Korean male workers in different age groups. Methods: The study sample was a weighted population of 3,289 (3,289 survey samples) men aged 20 to 64 years who responded to the 2006 Korean Working Condition Survey. Social support from colleague and supervisor, work autonomy, psychological wellbeing at work, and intellectual and emotional work demand were assessed. Results: After considering sociodemographic factors, smoking, occupational characteristics and other psychosocial work environment factors, problem drinking was associated with "intellectual work demand" for the 20~34 year old group. Social support from colleague and supervisor was significantly associated with problem drinking in the 35~49 year old group. For the 50~64 year old group, problem drinking was associated with 'work autonomy'. Conclusion: The present study clarified that certain psychosocial work environmental factors relate to problem drinking, and the association varies among different age groups.

The Impact of Weight Changes on Metabolic Syndrome over a Time period of 8 years in Korean Male Workers

The Impact of Weight Changes on Metabolic Syndrome over a Time period of 8 years in Korean Male Workers

Weight gain within the normal weight range predicts ultrasonographically detected fatty liver in healthy Korean men

Objectives:We performed a prospective study to determine whether weight gain predicts future ultrasonographically detected fatty liver (USFL) in a lean adult population.Methods:Among 15 347 Korean male workers, aged 30–59 years,...

Overweight of Korean male workers and genetic polymorphism of insulin receptor substrate 1 (IRS1) gene

We have examined the hypothesis that the Gly972Arg variant of the insulin receptor substrate 1 (IRS1) gene is associated with the components contributing to overweight (obesity) and metabolic syndrome. We describe IRS1 genotype frequencies in 274 Korean men. The frequencies of Gly972Gly (G/G) and Gly972Arg (G/A variant) of the IRS1 gene were 88.3% and 11.7%, respectively, and the differences in frequencies between the overweight (BMI≥25 kg/m2) group and non‐overweight (BMI<25 kg/m2) group were statistically significant. The subjects with G/A variant of IRS1 gene in non‐overweight had significantly higher level of visceral fat thickness and adiponectin/leptin ratio than those with G/G alleles. In overweight group, the subjects with G/A variant of IRS1 gene also showed significantly higher level of insulin than those with G/G alleles. These results suggest that the IRS1 genetic polymorphism is involved in the occurrence of overweight, as well as metabolic syndrome.

A study on health‐related lifestyle, nutrition intake and diet quality of Korean male workers according to cigarettes smoking (pack/year)

This study was performed to compare the lifestyles, dietary behaviors, nutrient intakes, and diet quality of male adult workers aged 20–50 years in Korea according to smoking history. Subjects were recruited and divided into three groups according to the smoking history (pack‐year), which included non‐smoker (n=40), light‐smoker (n=26; pack‐year ≤10), and heavy‐smoker (n=24; pack‐year &gt; 10). The heavy‐smokers more often ate irregular meals compared with the other two groups (p&lt; 0.001). Intakes of carbohydrate (p&lt; 0.05), Vitamin C (p&lt; 0.05), Plant calcium (p&lt;0.05), Iron (p&lt; 0.01), animal iron (p&lt;0.05), Zinc (p&lt;0.05) of light‐smokers and heavy‐smokers were lower than non‐smoker. INQ (Index of Nutritional Quality) of these nutrients in the two smoker groups were lower than for non‐smokers. Male smokers have low intake status of Vitamin C, Calcium, Iron, Zinc, and partly low diet quality. This research suggested that increased nutrition education and revised guidelines for smokers are needed.

The K121Q Polymorphism in ENPP1 (PC-1) Is Not Associated with Type 2 Diabetes or Obesity in Korean Male Workers

Type 2 diabetes is characterized by insulin resistance, and ENPP1 plays an important role in insulin resistance. We investigated the association of the ENPP1 K121Q polymorphism with both diabetes and obesity (body mass index [BMI]) in Korean male workers. The study design was case-control. Subjects were 1,945 male workers (type 2 diabetes, 195; non-diabetes, 1,750) of nuclear power plants who received examinations from March to October in 2004. We collected venous blood samples under fasting (≥8 hr) conditions, calculated BMI by height and weight, and assessed relevant biochemical factors. The results of this study demonstrated that the ENPP1 121Q genotype (KQ+QQ types) was not associated with type 2 diabetes (odds ratios [OR], 0.854; 95% confidence interval [CI], 0.571-1.278) or obesity (OR, 0.933; 95% CI, 0.731-1.190). In addition, the frequency of the Q allele was not related to type 2 diabetes (OR, 0.911; 95% CI, 0.630-1.319) or obesity (OR, 0.962; 95% CI, 0.767-1.205). We concluded that the ENPP1 121Q allele is not a critical determinant for either diabetes or obesity in Korean males. The discordance between the results of this study and those derived from studies of Dominican, South Asian, Caucasian, Finnish, and French populations might be due to differences in genetic backgrounds between these populations.

Distribution and determinants of maximal physical work capacity of Korean male metal workers

The distribution of maximal physical work capacity (MPWC) can be used to establish an upper limit for energy expenditure during work (EEwork). If physically demanding work has wearing effects, there will be a negative relationship between MPWC and workload. This study was conducted to investigate the distribution of MPWC among Korean metal workers and to examine the relationship between workload and MPWC. MPWC was estimated with a bicycle ergometer using a submaximal test. Energy expenditure was estimated by measuring heart rates during work. The study subjects were 507 male employees from several metal industries in Korea. They had a lower absolute VO2max than the Caucasian populations described in previous studies. The older workers had a lower physical capacity and a greater overload at work. A negative relationship was found between MPWC and workload across all age groups. Upper limits for EEwork for all age groups and for older age groups are recommended based on the 5th percentile value of MPWC.

Incidence and Risk Factors for Metabolic Syndrome in Korean Male Workers, Ages 30 to 39

There are few prospective data on the incidence of metabolic syndrome. The goals of this study were to define the incidence of and specific risk factors for metabolic syndrome (MetS) in Korean male workers 30 to 39 years of age. A prospective cohort study was undertaken involving 4,779 male workers, 30 to 39 years of age, who did not take medication for dyslipidemia or have a history of any malignancy at study entry. Subjects were reexamined annually at a university hospital in Seoul, Korea, over a 3-year period between 2002 to August 2005. A modified National Cholesterol Education Program definition of MetS with body mass index was used instead of waist circumference. Cox proportional hazards models were used to calculate adjusted hazard ratios in separate models for MetS. At the end of the 3-year follow-up period, MetS developed in 708 individuals. The unadjusted incidence density of MetS was 70.5 (95% CI, 65.3 approximately 75.37), and the age-adjusted incidence density of MetS was 76.9 per 1,000 person-years (95% CI, 67.8 approximately 86.1). Among a variety of candidate risk factors, uric acid, weight change, gamma-glutamyltranspeptidase, and alanine aminotransferase were independent risk predictors for MetS. The high-incidence density of this MetS in Korea may be an indicator of future increases in diabetes and cardiovascular disease.

Incidence and Risk Factors of Insulin Resistance Syndrome in 20-59 Year-Old Korean Male Workers

We investigated the incidence of insulin resistance syndrome (IRS) according to the criteria of diagnoses suggested by the American College of Endocrinology/American Association of Clinical Endocrinologists and the risk factors associated with the development of IRS. Among 2,048 subjects without a history of/or drug treatment for hypertension, diabetes, dyslipidemia with normal findings at baseline, 1,578 subjects aged 20-59 yr were followed prospectively for 2 yr. The incidence of IRS was 6.9 per 100 persons/year. The relative risk (RR) due to age was 1.03 (95% CI: 1.00-1.05) with every one-year increase in age. The RR associated with an abnormal waist-hip ratio group (≥0.9) was increased by 1.74 (95% CI:1.17-2.58) compared to the normal group (<0.9); RR associated with abnormal alanine transferase was increased (≥35 IU/L) by 1.70 (95% CI: 1.20-2.41) compared to the normal group (<35 IU/L); and the RR associated with abnormal low-density lipoprotein (LDL) cholesterol was increased (≥160 mg/L) by 1.70 (95% CI: 1.19-2.44) compared to the normal LDL cholesterol (<160 mg/L). Lastly, the RR of current smokers was increased by 1.63 (95% CI: 1.09-2.42) compared to that of non-smokers. It is necessary to develop methods of prevention and therapeutic approach to manage the integrated risk factors as opposed to individual factors.

Comparison of Risk Factors Between Prehypertension and Hypertension in Korean Male Industrial Workers

To compare risk factors for prehypertension and hypertension in male industrial workers in Korea. Participants included 2,476 males aged 19-56 years who were employed in an airplane manufacturing industry. Health records of all subjects were analyzed during a biennial employee physical checkup that included a health survey questionnaire and blood tests. Forty-six percent of subjects had prehypertension and 15% had hypertension. Multivariate logistic regression analysis showed that, after adjustment for age, workplace, and risk variables, subjects who were currently alcohol drinkers, in blue collar jobs, body mass index (BMI) > or =25 kg/m(2), and had cholesterol > or =201 mg/dl were 1.30, 1.28, 1.27, and 1.21 times more likely to have prehypertension respectively, compared with normotensives. Subjects with FBS> or =121 mg/dl, BMI> or =25 kg/m(2), and age> or =40 years were 2.47, 1.52, and 1.36 times more likely to have hypertension respectively, compared with prehypertensive subjects. Nurses working in the industrial sector should focus on education and counseling regarding the risk factors for prehypertension and hypertension, and they should emphasize the importance of healthy lifestyles and curbing obesity to help arrest the progression of prehypertension to hypertension.

Validation of High Performance Liquid Chromatographic Method with UV Detector for the Determination of Di(2-ethylhexyl)Phthalate in Plasma in some Korean Male Workers

2) Objectives: This study was conducted to validate a simple, rapid and sensitive reverse-phase high-per formance liquid chromatographic method with UV detector (HPLC-UV) and present the plasma level of di(2-ethylhexyl)phthalate (DEHP) in some Korean male workers. M e t h o d s: HPLC-UV for quantification of plasma DEHP was validated by the following guideline from the Center for Drug Evaluation and Research (CDER) - calibration/standard curve, precision, accu racy and recovery. Plasma DEHP from 255 healthy Korean male workers aged from 30 to 60 years was analyzed by validated HPLC-UV method. R e s u l t s: The calibration curve over the range 0~150 μg /l for the plasma DEHP standard solution showed linearity(r 2 =0.999). The limit of detection (LOD) and limit of quantificatio n (LOQ) of plasma DEHP were 5.22 μg /l and 15.81 μg /l, respectively. The accuracy and precision for 2.5 μg /l o f DEHP were acceptable in CDER guideline on the second and third day but not first day, and those for 50 μg /l and 150 μg /l of DEHP were acceptable on all three days(Ed-confirm this addition). The distribu tion of plasma DEHP level was skewed to the left and ranged from 0 to 18.9 μg /l. The plasma DEHP level was lower than 10 μg /l for 98 % of subjects and lower than 5 μg /lfor 85 %. The geometric mean and standard deviation of plasma DEHP were 0.4±1.5 μg /l. C o n c l u s i o n s : The HPLC-UV method for quantification of plasma DEHP was acceptable by CDER guideline. The plasma DEHP of 255 Korean male workers ranged from 0 to 18.9 μg /l and the distribu tion was skewed to the left.

Job stress and cardiovascular risk factors in male workers

Background. This study examined whether job stress (work demand and decision latitude) is associated with smoking, blood pressure, lipid level (total cholesterol, triglyceride, HDL cholesterol), and homocystein as risk factors for cardiovascular disease in Korean male workers. Methods. Study subjects of this study were recruited from a sample of 1,071 workers in 20 companies of W city and H counties, and they were grouped into four categories (high strain group, active group, passive group, and low strain group) based on the postulation of Karasek's Job Strain Model. Of them, we invited 160 male workers (40 people each subgroup) using a stratified sampling, and finally, 152 eligible participants were analyzed. Results. In multivariate analyses, we found that decision latitude was associated with cholesterol, triglyceride, and homocystein and that work demand was related to smoking and systolic blood pressure. Job strain (the combination of high work demand with low decision latitude) was significantly related to higher levels of homocystein after controlling for age, BMI, smoking, and social support at workplace. Conclusions. These results indicate that job stress is associated with cardiovascular risk factors and might contribute to the development of cardiovascular disease. Some considerations for the future research were discussed.

Cross-sectional study of blood lead effects on iron status in Korean lead workers

Objective This study assessed the iron status of Korean male lead workers by measuring the dietary iron intake and biochemical indices, and tested the hypothesis that a high blood lead level is associated with impaired iron function, which results in higher prevalence of iron deficiency when the route of exposure is not the gastrointestinal tract. Methods One hundred eighteen lead workers and 42 non–lead workers were recruited from mandatory annual health surveillance sites for industrial workers. Blood lead, hemoglobin, and hematocrit levels were evaluated as hematologic parameters, and serum iron concentrations, total iron-binding capacity, and percentage of transferrin saturation were evaluated as iron-status parameters. Dietary iron intake was assessed by a 24-h recall method. Results Lead workers had significantly lower hemoglobin, hematocrit, serum iron levels, percentage of transferrin saturation, and dietary iron intake than did non–lead workers, and they had significantly higher ( P < 0.01) total iron-binding capacity. The occurrence of iron-deficiency cases, as assessed by hematocrit values, was significantly higher ( P < 0.001) in lead workers than in non–lead workers, and the prevalence of iron deficiency was associated with high blood lead levels ( P = 0.033). The dietary iron intake was inversely associated with zinc protoporphyrin ( P = 0.032). Conclusions This study confirmed the adverse effects of high blood lead levels on hematologic pathways and the effectiveness of dietary iron intake as a secondary preventive intervention against lead toxicity. To promote health and to prevent toxic effects of lead exposure in Korean lead workers, an adequate intake of dietary iron is strongly recommended.

Sleep-wake behavior of shift workers using wrist actigraph.

The sleep-wake behavior and the effects of aging on the tolerance of night shift were investigated using wrist actigraph for 12 Korean male workers of a continuous full-day three-team three-shift system. The wrist actigraph data were obtained for about 21 days (1 shift cycle) for each subject. During night duty, total sleep time decreased, the number of naps and nap length during on-duty or off-duty periods increased, and the level of activity decreased with increasing age. These results suggest that the tolerance to night shift becomes weaker with increasing age.

Fit factors for quarter masks and facial size categories

Respirator fit testing is necessary before entering hazardous working environments to ensure that the respirator, when worn, satisfies a minimum fit and that the wearer knows when the respirator fits properly. In the many countries that do not have fit testing or total inward leakage regulations (including Korea), however, many workers wearing respirators may be potentially exposed to hazardous environments. It is necessary to suggest a useful tool to provide an alternative for fit testing in these countries. This study was conducted to evaluate fitting performance for quarter-mask respirators, and fit factors in facial size categories based on face lengths and lip lengths of the wearers. A total of 778 subjects (408 males, 370 females) were fit tested for three quarter masks: Sejin Co. SK-6 (Ulsan, Korea), Yongsung Co. YS-2010 S (Seoul, Korea), and 3 M Co. Series 7500 Medium (MN, USA) masks with a PortaCount 8020 (TSI Co., USA). A facial dimension survey of the subjects was conducted to develop facial size categories, on the basis of face length and lip length. Geometric mean fit factors (GMFFs) of Series 7500 Medium were found to be the highest of the three respirators. All of the respirators were more suitable for males than females in fitting performance. The Series 7500 Medium fitted a large number of the males tested, since the GMFFs for males were above 100 for every box of facial size categories, and high pass proportion rates were shown at an individual fit factor level of 100. The YS-2010 S provides an adequate fit for males in a limited range of facial dimensions. The Series 7500 Medium is more limited in providing adequate fit for females at specific facial dimensions than for males. For adequate fitting performance, the SK-6 is not preferentially recommended for Korean male and female workers due to low GMFFs and pass proportions. The result of this study indicates that after more accurate studies are performed, facial size categories, on the basis of facial dimensions, could be a useful tool to assist in the selection of adequately fitting respirators for workers in the countries having no fit testing requirements.

Fit factors for quarter masks and facial size categories

Respirator fit testing is necessary before entering hazardous working environments to ensure that the respirator, when worn, satisfies a minimum fit and that the wearer knows when the respirator fits properly. In the many countries that do not have fit testing or total inward leakage regulations (including Korea), however, many workers wearing respirators may be potentially exposed to hazardous environments. It is necessary to suggest a useful tool to provide an alternative for fit testing in these countries. This study was conducted to evaluate fitting performance for quarter-mask respirators, and fit factors in facial size categories based on face lengths and lip lengths of the wearers. A total of 778 subjects (408 males, 370 females) were fit tested for three quarter masks: Sejin Co. SK-6 (Ulsan, Korea), Yongsung Co. YS-2010 S (Seoul, Korea), and 3 M Co. Series 7500 Medium (MN, USA) masks with a PortaCount 8020 (TSI Co., USA). A facial dimension survey of the subjects was conducted to develop facial size categories, on the basis of face length and lip length. Geometric mean fit factors (GMFFs) of Series 7500 Medium were found to be the highest of the three respirators. All of the respirators were more suitable for males than females in fitting performance. The Series 7500 Medium fitted a large number of the males tested, since the GMFFs for males were above 100 for every box of facial size categories, and high pass proportion rates were shown at an individual fit factor level of 100. The YS-2010 S provides an adequate fit for males in a limited range of facial dimensions. The Series 7500 Medium is more limited in providing adequate fit for females at specific facial dimensions than for males. For adequate fitting performance, the SK-6 is not preferentially recommended for Korean male and female workers due to low GMFFs and pass proportions. The result of this study indicates that after more accurate studies are performed, facial size categories, on the basis of facial dimensions, could be a useful tool to assist in the selection of adequately fitting respirators for workers in the countries having no fit testing requirements.

Normal Predictive Values of FVC and FEV1 for Healthy Korean Male Workers

Normal Predictive Values of FVC and FEV1 for Healthy Korean Male Workers